refactor: Rename computeMinScale to computeCoarsestScale and remove unused asset parameter

The function returns the maximum (coarsest) exponent, not the minimum
scale. Rename to computeCoarsestScale to accurately reflect behavior.
Also remove the unused Asset parameter from the signature.

.clang-tidy

@@ -104,10 +104,13 @@ Checks: "-*,
   readability-const-return-type,
   readability-container-contains,
   readability-container-size-empty,
+  readability-convert-member-functions-to-static,
   readability-duplicate-include,
   readability-else-after-return,
   readability-enum-initial-value,
+  readability-implicit-bool-conversion,
   readability-make-member-function-const,
+  readability-math-missing-parentheses,
   readability-misleading-indentation,
   readability-non-const-parameter,
   readability-redundant-casting,
@@ -116,7 +119,9 @@ Checks: "-*,
   readability-redundant-member-init,
   readability-redundant-string-init,
   readability-reference-to-constructed-temporary,
+  readability-simplify-boolean-expr,
   readability-static-definition-in-anonymous-namespace,
+  readability-suspicious-call-argument,
   readability-use-std-min-max
   "
 # ---
@@ -127,14 +132,9 @@ Checks: "-*,
 # misc-include-cleaner,
 # misc-redundant-expression,
 #
-# readability-convert-member-functions-to-static,
-# readability-implicit-bool-conversion,
-# readability-inconsistent-declaration-parameter-name,
+# readability-inconsistent-declaration-parameter-name, # in this codebase this check will break a lot of arg names
+# readability-static-accessed-through-instance,        # this check is probably unnecessary. it makes the code less readable
 # readability-identifier-naming,
-# readability-math-missing-parentheses,
-# readability-simplify-boolean-expr,
-# readability-suspicious-call-argument,
-# readability-static-accessed-through-instance,
 #
 # modernize-concat-nested-namespaces,
 # modernize-pass-by-value,

.github/scripts/levelization/results/ordering.txt

@@ -90,6 +90,7 @@ test.core > xrpl.server
 test.csf > xrpl.basics
 test.csf > xrpld.consensus
 test.csf > xrpl.json
+test.csf > xrpl.ledger
 test.csf > xrpl.protocol
 test.json > test.jtx
 test.json > xrpl.json
@@ -108,7 +109,6 @@ test.jtx > xrpl.tx
 test.ledger > test.jtx
 test.ledger > test.toplevel
 test.ledger > xrpl.basics
-test.ledger > xrpld.app
 test.ledger > xrpld.core
 test.ledger > xrpl.ledger
 test.ledger > xrpl.protocol
@@ -125,6 +125,7 @@ test.overlay > xrpl.basics
 test.overlay > xrpld.app
 test.overlay > xrpld.overlay
 test.overlay > xrpld.peerfinder
+test.overlay > xrpl.ledger
 test.overlay > xrpl.nodestore
 test.overlay > xrpl.protocol
 test.overlay > xrpl.shamap
@@ -234,6 +235,7 @@ xrpld.app > xrpl.shamap
 xrpld.app > xrpl.tx
 xrpld.consensus > xrpl.basics
 xrpld.consensus > xrpl.json
+xrpld.consensus > xrpl.ledger
 xrpld.consensus > xrpl.protocol
 xrpld.core > xrpl.basics
 xrpld.core > xrpl.core

.github/workflows/conflicting-pr.yml

@@ -0,0 +1,25 @@
+name: Label PRs with merge conflicts
+
+on:
+  # So that PRs touching the same files as the push are updated.
+  push:
+  # So that the `dirtyLabel` is removed if conflicts are resolved.
+  # We recommend `pull_request_target` so that github secrets are available.
+  # In `pull_request` we wouldn't be able to change labels of fork PRs.
+  pull_request_target:
+    types: [synchronize]
+
+permissions:
+  pull-requests: write
+
+jobs:
+  main:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check if PRs are dirty
+        uses: eps1lon/actions-label-merge-conflict@1df065ebe6e3310545d4f4c4e862e43bdca146f0 # v3.0.3
+        with:
+          dirtyLabel: "PR: has conflicts"
+          repoToken: "${{ secrets.GITHUB_TOKEN }}"
+          commentOnDirty: "This PR has conflicts, please resolve them in order for the PR to be reviewed."
+          commentOnClean: "All conflicts have been resolved. Assigned reviewers can now start or resume their review."

.github/workflows/reusable-build-test-config.yml

@@ -298,7 +298,7 @@ jobs:
 
       - name: Upload coverage report
         if: ${{ github.repository == 'XRPLF/rippled' && !inputs.build_only && env.COVERAGE_ENABLED == 'true' }}
-        uses: codecov/codecov-action@671740ac38dd9b0130fbe1cec585b89eea48d3de # v5.5.2
+        uses: codecov/codecov-action@1af58845a975a7985b0beb0cbe6fbbb71a41dbad # v5.5.3
         with:
           disable_search: true
           disable_telem: true

.github/workflows/reusable-clang-tidy.yml

@@ -51,5 +51,5 @@ jobs:
     if: ${{ always() && !cancelled() && (!inputs.check_only_changed || needs.determine-files.outputs.any_cpp_changed == 'true' || needs.determine-files.outputs.clang_tidy_config_changed == 'true') }}
     uses: ./.github/workflows/reusable-clang-tidy-files.yml
     with:
-      files: ${{ needs.determine-files.outputs.clang_tidy_config_changed == 'true' && '' || (inputs.check_only_changed && needs.determine-files.outputs.all_changed_files || '') }}
+      files: ${{ (needs.determine-files.outputs.clang_tidy_config_changed != 'true' && inputs.check_only_changed) && needs.determine-files.outputs.all_changed_files || '' }}
       create_issue_on_failure: ${{ inputs.create_issue_on_failure }}

.gitignore

@@ -71,6 +71,8 @@ DerivedData
 /.zed/
 
 # AI tools.
+/.agent
+/.agents
 /.augment
 /.claude
 /CLAUDE.md

BUILD.md

@@ -125,9 +125,9 @@ default profile.
 
 ### Patched recipes
 
-The recipes in Conan Center occasionally need to be patched for compatibility
-with the latest version of `xrpld`. We maintain a fork of the Conan Center
-[here](https://github.com/XRPLF/conan-center-index/) containing the patches.
+Occasionally, we need patched recipes or recipes not present in Conan Center.
+We maintain a fork of the Conan Center Index
+[here](https://github.com/XRPLF/conan-center-index/) containing the modified and newly added recipes.
 
 To ensure our patched recipes are used, you must add our Conan remote at a
 higher index than the default Conan Center remote, so it is consulted first. You
@@ -137,19 +137,11 @@ can do this by running:
 conan remote add --index 0 xrplf https://conan.ripplex.io
 ```
 
-Alternatively, you can pull the patched recipes into the repository and use them
-locally:
+Alternatively, you can pull our recipes from the repository and export them locally:
 
 ```bash
-# Extract the version number from the lockfile.
-function extract_version {
-  version=$(cat conan.lock | sed -nE "s@.+${1}/(.+)#.+@\1@p" | head -n1)
-  echo ${version}
-}
-
 # Define which recipes to export.
-recipes=('ed25519' 'grpc' 'nudb' 'openssl' 'secp256k1' 'snappy' 'soci')
-folders=('all'     'all'  'all'  '3.x.x'   'all'       'all'    'all')
+recipes=('abseil' 'ed25519' 'grpc' 'm4' 'mpt-crypto' 'nudb' 'openssl' 'secp256k1' 'snappy' 'soci' 'wasm-xrplf' 'wasmi')
 
 # Selectively check out the recipes from our CCI fork.
 cd external
@@ -158,29 +150,19 @@ cd conan-center-index
 git init
 git remote add origin git@github.com:XRPLF/conan-center-index.git
 git sparse-checkout init
-for ((index = 1; index <= ${#recipes[@]}; index++)); do
-  recipe=${recipes[index]}
-  folder=${folders[index]}
-  echo "Checking out recipe '${recipe}' from folder '${folder}'..."
-  git sparse-checkout add recipes/${recipe}/${folder}
+for recipe in "${recipes[@]}"; do
+  echo "Checking out recipe '${recipe}'..."
+  git sparse-checkout add recipes/${recipe}
 done
 git fetch origin master
 git checkout master
-cd ../..
 
-# Export the recipes into the local cache.
-for ((index = 1; index <= ${#recipes[@]}; index++)); do
-  recipe=${recipes[index]}
-  folder=${folders[index]}
-  version=$(extract_version ${recipe})
-  echo "Exporting '${recipe}/${version}' from '${recipe}/${folder}'..."
-  conan export --version $(extract_version ${recipe}) \
-    external/conan-center-index/recipes/${recipe}/${folder}
-done
+./export_all.sh
+cd ../../
 ```
 
 In the case we switch to a newer version of a dependency that still requires a
-patch, it will be necessary for you to pull in the changes and re-export the
+patch or add a new dependency, it will be necessary for you to pull in the changes and re-export the
 updated dependencies with the newer version. However, if we switch to a newer
 version that no longer requires a patch, no action is required on your part, as
 the new recipe will be automatically pulled from the official Conan Center.
@@ -189,6 +171,8 @@ the new recipe will be automatically pulled from the official Conan Center.
 > You might need to add `--lockfile=""` to your `conan install` command
 > to avoid automatic use of the existing `conan.lock` file when you run
 > `conan export` manually on your machine
+>
+> This is not recommended though, as you might end up using different revisions of recipes.
 
 ### Conan profile tweaks
 
@@ -204,39 +188,14 @@ Possible values are ['5.0', '5.1', '6.0', '6.1', '7.0', '7.3', '8.0', '8.1',
 Read "http://docs.conan.io/2/knowledge/faq.html#error-invalid-setting"
 ```
 
-you need to amend the list of compiler versions in
-`$(conan config home)/settings.yml`, by appending the required version number(s)
+you need to add your compiler to the list of compiler versions in
+`$(conan config home)/settings_user.yml`, by adding the required version number(s)
 to the `version` array specific for your compiler. For example:
 
 ```yaml
-apple-clang:
-  version:
-    [
-      "5.0",
-      "5.1",
-      "6.0",
-      "6.1",
-      "7.0",
-      "7.3",
-      "8.0",
-      "8.1",
-      "9.0",
-      "9.1",
-      "10.0",
-      "11.0",
-      "12.0",
-      "13",
-      "13.0",
-      "13.1",
-      "14",
-      "14.0",
-      "15",
-      "15.0",
-      "16",
-      "16.0",
-      "17",
-      "17.0",
-    ]
+compiler:
+  apple-clang:
+    version: ["17.0"]
 ```
 
 #### Multiple compilers

CONTRIBUTING.md

@@ -259,6 +259,10 @@ There is a Continuous Integration job that runs clang-tidy on pull requests. The
 
 This ensures that configuration changes don't introduce new warnings across the codebase.
 
+### Installing clang-tidy
+
+See the [environment setup guide](./docs/build/environment.md#clang-tidy) for platform-specific installation instructions.
+
 ### Running clang-tidy locally
 
 Before running clang-tidy, you must build the project to generate required files (particularly protobuf headers). Refer to [`BUILD.md`](./BUILD.md) for build instructions.
@@ -266,10 +270,15 @@ Before running clang-tidy, you must build the project to generate required files
 Then run clang-tidy on your local changes:
 
 ```
-run-clang-tidy -p build src tests
+run-clang-tidy -p build src include tests
 ```
 
-This will check all source files in the `src` and `tests` directories using the compile commands from your `build` directory.
+This will check all source files in the `src`, `include` and `tests` directories using the compile commands from your `build` directory.
+If you wish to automatically fix whatever clang-tidy finds _and_ is capable of fixing, add `-fix` to the above command:
+
+```
+run-clang-tidy -p build -fix src include tests
+```
 
 ## Contracts and instrumentation
 

LICENSE.md

@@ -1,7 +1,7 @@
 ISC License
 
 Copyright (c) 2011, Arthur Britto, David Schwartz, Jed McCaleb, Vinnie Falco, Bob Way, Eric Lombrozo, Nikolaos D. Bougalis, Howard Hinnant.
-Copyright (c) 2012-2025, the XRP Ledger developers.
+Copyright (c) 2012-present, the XRP Ledger developers.
 
 Permission to use, copy, modify, and distribute this software for any
 purpose with or without fee is hereby granted, provided that the above

cmake/XrplProtocolAutogen.cmake

@@ -140,6 +140,28 @@ function(setup_protocol_autogen)
                 )
             endif()
 
+            # Check pip index URL configuration
+            execute_process(
+                COMMAND ${VENV_PIP} config get global.index-url
+                OUTPUT_VARIABLE PIP_INDEX_URL
+                OUTPUT_STRIP_TRAILING_WHITESPACE
+                ERROR_QUIET
+            )
+
+            # Default PyPI URL
+            set(DEFAULT_PIP_INDEX "https://pypi.org/simple")
+
+            # Show warning if using non-default index
+            if(PIP_INDEX_URL AND NOT PIP_INDEX_URL STREQUAL "")
+                if(NOT PIP_INDEX_URL STREQUAL DEFAULT_PIP_INDEX)
+                    message(
+                        WARNING
+                        "Private pip index URL detected: ${PIP_INDEX_URL}\n"
+                        "You may need to connect to VPN to access this URL."
+                    )
+                endif()
+            endif()
+
             message(STATUS "Installing Python dependencies...")
             execute_process(
                 COMMAND ${VENV_PIP} install --upgrade pip

conan.lock

@@ -1,16 +1,16 @@
 {
     "version": "0.5",
     "requires": [
-        "zlib/1.3.1#b8bc2603263cf7eccbd6e17e66b0ed76%1765850150.075",
+        "zlib/1.3.1#cac0f6daea041b0ccf42934163defb20%1774439233.809",
         "xxhash/0.8.3#681d36a0a6111fc56e5e45ea182c19cc%1765850149.987",
-        "sqlite3/3.49.1#8631739a4c9b93bd3d6b753bac548a63%1765850149.926",
-        "soci/4.0.3#a9f8d773cd33e356b5879a4b0564f287%1765850149.46",
+        "sqlite3/3.51.0#66aa11eabd0e34954c5c1c061ad44abe%1763899256.358",
+        "soci/4.0.3#fe32b9ad5eb47e79ab9e45a68f363945%1774450067.231",
         "snappy/1.1.10#968fef506ff261592ec30c574d4a7809%1765850147.878",
-        "secp256k1/0.7.1#3a61e95e220062ef32c48d019e9c81f7%1770306721.686",
+        "secp256k1/0.7.1#481881709eb0bdd0185a12b912bbe8ad%1770910500.329",
         "rocksdb/10.5.1#4a197eca381a3e5ae8adf8cffa5aacd0%1765850186.86",
-        "re2/20230301#ca3b241baec15bd31ea9187150e0b333%1765850148.103",
-        "protobuf/6.32.1#f481fd276fc23a33b85a3ed1e898b693%1765850161.038",
-        "openssl/3.5.5#05a4ac5b7323f7a329b2db1391d9941f%1769599205.414",
+        "re2/20251105#8579cfd0bda4daf0683f9e3898f964b4%1774398111.888",
+        "protobuf/6.33.5#d96d52ba5baaaa532f47bda866ad87a5%1773224203.27",
+        "openssl/3.6.1#e6399de266349245a4542fc5f6c71552%1774458290.139",
         "nudb/2.0.9#0432758a24204da08fee953ec9ea03cb%1769436073.32",
         "lz4/1.10.0#59fc63cac7f10fbe8e05c7e62c2f3504%1765850143.914",
         "libiconv/1.17#1e65319e945f2d31941a9d28cc13c058%1765842973.492",
@@ -18,27 +18,26 @@
         "libarchive/3.8.1#ffee18995c706e02bf96e7a2f7042e0d%1765850144.736",
         "jemalloc/5.3.0#e951da9cf599e956cebc117880d2d9f8%1729241615.244",
         "gtest/1.17.0#5224b3b3ff3b4ce1133cbdd27d53ee7d%1768312129.152",
-        "grpc/1.72.0#f244a57bff01e708c55a1100b12e1589%1765850193.734",
+        "grpc/1.78.1#b1a9e74b145cc471bed4dc64dc6eb2c1%1772623605.068",
         "ed25519/2015.03#ae761bdc52730a843f0809bdf6c1b1f6%1765850143.772",
         "date/3.0.4#862e11e80030356b53c2c38599ceb32b%1765850143.772",
-        "c-ares/1.34.5#5581c2b62a608b40bb85d965ab3ec7c8%1765850144.336",
+        "c-ares/1.34.6#545240bb1c40e2cacd4362d6b8967650%1774439234.681",
         "bzip2/1.0.8#c470882369c2d95c5c77e970c0c7e321%1765850143.837",
         "boost/1.90.0#d5e8defe7355494953be18524a7f135b%1769454080.269",
-        "abseil/20250127.0#99262a368bd01c0ccca8790dfced9719%1766517936.993"
+        "abseil/20250127.0#bb0baf1f362bc4a725a24eddd419b8f7%1774365460.196"
     ],
     "build_requires": [
-        "zlib/1.3.1#b8bc2603263cf7eccbd6e17e66b0ed76%1765850150.075",
-        "strawberryperl/5.32.1.1#707032463aa0620fa17ec0d887f5fe41%1765850165.196",
-        "protobuf/6.32.1#f481fd276fc23a33b85a3ed1e898b693%1765850161.038",
+        "zlib/1.3.1#cac0f6daea041b0ccf42934163defb20%1774439233.809",
+        "strawberryperl/5.32.1.1#8d114504d172cfea8ea1662d09b6333e%1774447376.964",
+        "protobuf/6.33.5#d96d52ba5baaaa532f47bda866ad87a5%1773224203.27",
         "nasm/2.16.01#31e26f2ee3c4346ecd347911bd126904%1765850144.707",
-        "msys2/cci.latest#eea83308ad7e9023f7318c60d5a9e6cb%1770199879.083",
-        "m4/1.4.19#70dc8bbb33e981d119d2acc0175cf381%1763158052.846",
-        "cmake/4.2.0#ae0a44f44a1ef9ab68fd4b3e9a1f8671%1765850153.937",
-        "cmake/3.31.10#313d16a1aa16bbdb2ca0792467214b76%1765850153.479",
-        "b2/5.3.3#107c15377719889654eb9a162a673975%1765850144.355",
+        "msys2/cci.latest#d22fe7b2808f5fd34d0a7923ace9c54f%1770657326.649",
+        "m4/1.4.19#5d7a4994e5875d76faf7acf3ed056036%1774365463.87",
+        "cmake/4.3.0#b939a42e98f593fb34d3a8c5cc860359%1774439249.183",
+        "b2/5.4.2#ffd6084a119587e70f11cd45d1a386e2%1774439233.447",
         "automake/1.16.5#b91b7c384c3deaa9d535be02da14d04f%1755524470.56",
         "autoconf/2.71#51077f068e61700d65bb05541ea1e4b0%1731054366.86",
-        "abseil/20250127.0#99262a368bd01c0ccca8790dfced9719%1766517936.993"
+        "abseil/20250127.0#bb0baf1f362bc4a725a24eddd419b8f7%1774365460.196"
     ],
     "python_requires": [],
     "overrides": {
@@ -46,14 +45,14 @@
             null,
             "boost/1.90.0"
         ],
-        "protobuf/5.27.0": [
-            "protobuf/6.32.1"
+        "protobuf/[>=5.27.0 <7]": [
+            "protobuf/6.33.5"
         ],
         "lz4/1.9.4": [
             "lz4/1.10.0"
         ],
-        "sqlite3/3.44.2": [
-            "sqlite3/3.49.1"
+        "sqlite3/[>=3.44 <4]": [
+            "sqlite3/3.51.0"
         ],
         "boost/1.83.0": [
             "boost/1.90.0"

conanfile.py

@@ -1,10 +1,9 @@
-import re
 import os
+import re
 
 from conan.tools.cmake import CMake, CMakeToolchain, cmake_layout
 
 from conan import ConanFile
-from conan import __version__ as conan_version
 
 
 class Xrpl(ConanFile):
@@ -30,10 +29,10 @@ class Xrpl(ConanFile):
 
     requires = [
         "ed25519/2015.03",
-        "grpc/1.72.0",
+        "grpc/1.78.1",
         "libarchive/3.8.1",
         "nudb/2.0.9",
-        "openssl/3.5.5",
+        "openssl/3.6.1",
         "secp256k1/0.7.1",
         "soci/4.0.3",
         "zlib/1.3.1",
@@ -44,7 +43,7 @@ class Xrpl(ConanFile):
     ]
 
     tool_requires = [
-        "protobuf/6.32.1",
+        "protobuf/6.33.5",
     ]
 
     default_options = {
@@ -137,20 +136,16 @@ class Xrpl(ConanFile):
                 self.default_options["fPIC"] = False
 
     def requirements(self):
-        # Conan 2 requires transitive headers to be specified
-        transitive_headers_opt = (
-            {"transitive_headers": True} if conan_version.split(".")[0] == "2" else {}
-        )
-        self.requires("boost/1.90.0", force=True, **transitive_headers_opt)
-        self.requires("date/3.0.4", **transitive_headers_opt)
+        self.requires("boost/1.90.0", force=True, transitive_headers=True)
+        self.requires("date/3.0.4", transitive_headers=True)
         self.requires("lz4/1.10.0", force=True)
-        self.requires("protobuf/6.32.1", force=True)
-        self.requires("sqlite3/3.49.1", force=True)
+        self.requires("protobuf/6.33.5", force=True)
+        self.requires("sqlite3/3.51.0", force=True)
         if self.options.jemalloc:
             self.requires("jemalloc/5.3.0")
         if self.options.rocksdb:
             self.requires("rocksdb/10.5.1")
-        self.requires("xxhash/0.8.3", **transitive_headers_opt)
+        self.requires("xxhash/0.8.3", transitive_headers=True)
 
     exports_sources = (
         "CMakeLists.txt",

cspell.config.yaml

@@ -297,6 +297,7 @@ words:
   - venv
   - vfalco
   - vinnie
+  - wasmi
   - wextra
   - wptr
   - writeme

docs/build/environment.md

@@ -109,3 +109,32 @@ Install CMake with Homebrew too:
 ```
 brew install cmake
 ```
+
+## Clang-tidy
+
+Clang-tidy is required to run static analysis checks locally (see [CONTRIBUTING.md](../../CONTRIBUTING.md)).
+It is not required to build the project. Currently this project uses clang-tidy version 21.
+
+### Linux
+
+LLVM 21 is not available in the default Debian 12 (Bookworm) repositories.
+Install it using the official LLVM apt installer:
+
+```
+wget https://apt.llvm.org/llvm.sh
+chmod +x llvm.sh
+sudo ./llvm.sh 21
+sudo apt install --yes clang-tidy-21
+```
+
+Then use `run-clang-tidy-21` when running clang-tidy locally.
+
+### macOS
+
+Install LLVM 21 via Homebrew:
+
+```
+brew install llvm@21
+```
+
+Then use `run-clang-tidy` from the LLVM 21 Homebrew prefix when running clang-tidy locally.

include/xrpl/beast/utility/instrumentation.h

@@ -15,7 +15,7 @@
 #define ALWAYS_OR_UNREACHABLE(cond, message) assert((message) && (cond))
 #define SOMETIMES(cond, message, ...)
 #define REACHABLE(message, ...)
-#define UNREACHABLE(message, ...) assert((message) && false)
+#define UNREACHABLE(message, ...) assert((message) && false)  // NOLINT(misc-static-assert)
 #endif
 
 #define XRPL_ASSERT ALWAYS_OR_UNREACHABLE

include/xrpl/core/JobQueue.h

@@ -316,7 +316,7 @@ private:
     // Returns the limit of running jobs for the given job type.
     // For jobs with no limit, we return the largest int. Hopefully that
     // will be enough.
-    int
+    static int
     getJobLimit(JobType type);
 };
 

include/xrpl/core/ServiceRegistry.h

@@ -45,7 +45,7 @@ class NetworkIDService;
 class OpenLedger;
 class OrderBookDB;
 class Overlay;
-class PathRequests;
+class PathRequestManager;
 class PeerReservationTable;
 class PendingSaves;
 class RelationalDatabase;
@@ -195,8 +195,8 @@ public:
     virtual TxQ&
     getTxQ() = 0;
 
-    virtual PathRequests&
-    getPathRequests() = 0;
+    virtual PathRequestManager&
+    getPathRequestManager() = 0;
 
     // Server services
     virtual ServerHandler&

include/xrpl/ledger/Credit.h

@@ -1,43 +0,0 @@
-#pragma once
-
-#include <xrpl/ledger/View.h>
-#include <xrpl/protocol/IOUAmount.h>
-#include <xrpl/protocol/STAmount.h>
-
-namespace xrpl {
-
-/** Calculate the maximum amount of IOUs that an account can hold
-    @param ledger the ledger to check against.
-    @param account the account of interest.
-    @param issuer the issuer of the IOU.
-    @param currency the IOU to check.
-    @return The maximum amount that can be held.
-*/
-/** @{ */
-STAmount
-creditLimit(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency);
-
-IOUAmount
-creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur);
-/** @} */
-
-/** Returns the amount of IOUs issued by issuer that are held by an account
-    @param ledger the ledger to check against.
-    @param account the account of interest.
-    @param issuer the issuer of the IOU.
-    @param currency the IOU to check.
-*/
-/** @{ */
-STAmount
-creditBalance(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency);
-/** @} */
-
-}  // namespace xrpl

include/xrpl/ledger/Ledger.h

@@ -1,13 +1,12 @@
 #pragma once
 
-#include <xrpld/core/Config.h>
-#include <xrpld/core/TimeKeeper.h>
-
 #include <xrpl/basics/CountedObject.h>
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/CachedView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/protocol/Fees.h>
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Rules.h>
 #include <xrpl/protocol/STLedgerEntry.h>
 #include <xrpl/protocol/Serializer.h>
 #include <xrpl/protocol/TxMeta.h>
@@ -15,7 +14,7 @@
 
 namespace xrpl {
 
-class Application;
+class ServiceRegistry;
 class Job;
 class TransactionMaster;
 
@@ -83,21 +82,26 @@ public:
     */
     Ledger(
         create_genesis_t,
-        Config const& config,
+        Rules const& rules,
+        Fees const& fees,
         std::vector<uint256> const& amendments,
         Family& family);
 
-    Ledger(LedgerHeader const& info, Config const& config, Family& family);
+    Ledger(LedgerHeader const& info, Rules const& rules, Family& family);
 
     /** Used for ledgers loaded from JSON files
 
         @param acquire If true, acquires the ledger if not found locally
+
+        @note The fees parameter provides default values, but setup() may
+              override them from the ledger state if fee-related SLEs exist.
     */
     Ledger(
         LedgerHeader const& info,
         bool& loaded,
         bool acquire,
-        Config const& config,
+        Rules const& rules,
+        Fees const& fees,
         Family& family,
         beast::Journal j);
 
@@ -113,7 +117,8 @@ public:
     Ledger(
         std::uint32_t ledgerSeq,
         NetClock::time_point closeTime,
-        Config const& config,
+        Rules const& rules,
+        Fees const& fees,
         Family& family);
 
     ~Ledger() = default;
@@ -322,7 +327,7 @@ public:
     walkLedger(beast::Journal j, bool parallel = false) const;
 
     bool
-    assertSensible(beast::Journal ledgerJ) const;
+    isSensible() const;
 
     void
     invariants() const;
@@ -379,8 +384,26 @@ private:
     bool
     setup();
 
-    void
-    defaultFees(Config const& config);
+    /** @brief Deserialize a SHAMapItem containing a single STTx.
+     *
+     * @param item The SHAMapItem to deserialize.
+     * @return A shared pointer to the deserialized transaction.
+     * @throw May throw on deserialization error.
+     */
+    static std::shared_ptr<STTx const>
+    deserializeTx(SHAMapItem const& item);
+
+    /** @brief Deserialize a SHAMapItem containing STTx + STObject metadata.
+     *
+     * The SHAMapItem must contain two variable length serialization objects.
+     *
+     * @param item The SHAMapItem to deserialize.
+     * @return A pair containing shared pointers to the deserialized transaction
+     *         and metadata.
+     * @throw May throw on deserialization error.
+     */
+    static std::pair<std::shared_ptr<STTx const>, std::shared_ptr<STObject const>>
+    deserializeTxPlusMeta(SHAMapItem const& item);
 
     bool mImmutable;
 
@@ -402,54 +425,4 @@ private:
 /** A ledger wrapped in a CachedView. */
 using CachedLedger = CachedView<Ledger>;
 
-//------------------------------------------------------------------------------
-//
-// API
-//
-//------------------------------------------------------------------------------
-
-extern bool
-pendSaveValidated(
-    Application& app,
-    std::shared_ptr<Ledger const> const& ledger,
-    bool isSynchronous,
-    bool isCurrent);
-
-std::shared_ptr<Ledger>
-loadLedgerHelper(LedgerHeader const& sinfo, Application& app, bool acquire);
-
-std::shared_ptr<Ledger>
-loadByIndex(std::uint32_t ledgerIndex, Application& app, bool acquire = true);
-
-std::shared_ptr<Ledger>
-loadByHash(uint256 const& ledgerHash, Application& app, bool acquire = true);
-
-// Fetch the ledger with the highest sequence contained in the database
-extern std::tuple<std::shared_ptr<Ledger>, std::uint32_t, uint256>
-getLatestLedger(Application& app);
-
-/** Deserialize a SHAMapItem containing a single STTx
-
-    Throw:
-
-        May throw on deserializaton error
-*/
-std::shared_ptr<STTx const>
-deserializeTx(SHAMapItem const& item);
-
-/** Deserialize a SHAMapItem containing STTx + STObject metadata
-
-    The SHAMap must contain two variable length
-    serialization objects.
-
-    Throw:
-
-        May throw on deserializaton error
-*/
-std::pair<std::shared_ptr<STTx const>, std::shared_ptr<STObject const>>
-deserializeTxPlusMeta(SHAMapItem const& item);
-
-uint256
-calculateLedgerHash(LedgerHeader const& info);
-
 }  // namespace xrpl

include/xrpl/ledger/View.h

@@ -2,26 +2,23 @@
 
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/ApplyView.h>
-#include <xrpl/ledger/OpenView.h>
 #include <xrpl/ledger/ReadView.h>
-#include <xrpl/protocol/Asset.h>
-#include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/MPTIssue.h>
 #include <xrpl/protocol/Protocol.h>
-#include <xrpl/protocol/Rate.h>
 #include <xrpl/protocol/STLedgerEntry.h>
-#include <xrpl/protocol/STObject.h>
-#include <xrpl/protocol/Serializer.h>
+#include <xrpl/protocol/STTx.h>
 #include <xrpl/protocol/TER.h>
 
+#include <cstdint>
 #include <functional>
-#include <initializer_list>
 #include <map>
+#include <memory>
+#include <optional>
+#include <set>
 #include <utility>
 
 namespace xrpl {
 
-enum class WaiveTransferFee : bool { No = false, Yes };
 enum class SkipEntry : bool { No = false, Yes };
 
 //------------------------------------------------------------------------------
@@ -54,24 +51,6 @@ enum class SkipEntry : bool { No = false, Yes };
 [[nodiscard]] bool
 hasExpired(ReadView const& view, std::optional<std::uint32_t> const& exp);
 
-/** Controls the treatment of frozen account balances */
-enum FreezeHandling { fhIGNORE_FREEZE, fhZERO_IF_FROZEN };
-
-/** Controls the treatment of unauthorized MPT balances */
-enum AuthHandling { ahIGNORE_AUTH, ahZERO_IF_UNAUTHORIZED };
-
-/** Controls whether to include the account's full spendable balance */
-enum SpendableHandling { shSIMPLE_BALANCE, shFULL_BALANCE };
-
-[[nodiscard]] bool
-isGlobalFrozen(ReadView const& view, AccountID const& issuer);
-
-[[nodiscard]] bool
-isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
-
-[[nodiscard]] bool
-isGlobalFrozen(ReadView const& view, Asset const& asset);
-
 // Note, depth parameter is used to limit the recursion depth
 [[nodiscard]] bool
 isVaultPseudoAccountFrozen(
@@ -80,175 +59,6 @@ isVaultPseudoAccountFrozen(
     MPTIssue const& mptShare,
     int depth);
 
-[[nodiscard]] bool
-isIndividualFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer);
-
-[[nodiscard]] inline bool
-isIndividualFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
-{
-    return isIndividualFrozen(view, account, issue.currency, issue.account);
-}
-
-[[nodiscard]] bool
-isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
-
-[[nodiscard]] inline bool
-isIndividualFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
-{
-    return std::visit(
-        [&](auto const& issue) { return isIndividualFrozen(view, account, issue); }, asset.value());
-}
-
-[[nodiscard]] bool
-isFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer);
-
-[[nodiscard]] inline bool
-isFrozen(ReadView const& view, AccountID const& account, Issue const& issue, int = 0 /*ignored*/)
-{
-    return isFrozen(view, account, issue.currency, issue.account);
-}
-
-[[nodiscard]] bool
-isFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue, int depth = 0);
-
-/**
- *   isFrozen check is recursive for MPT shares in a vault, descending to
- *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
- *   purely defensive, as we currently do not allow such vaults to be created.
- */
-[[nodiscard]] inline bool
-isFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0)
-{
-    return std::visit(
-        [&](auto const& issue) { return isFrozen(view, account, issue, depth); }, asset.value());
-}
-
-[[nodiscard]] inline TER
-checkFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
-{
-    return isFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue)
-{
-    return isFrozen(view, account, mptIssue) ? (TER)tecLOCKED : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
-{
-    return std::visit(
-        [&](auto const& issue) { return checkFrozen(view, account, issue); }, asset.value());
-}
-
-[[nodiscard]] bool
-isAnyFrozen(
-    ReadView const& view,
-    std::initializer_list<AccountID> const& accounts,
-    MPTIssue const& mptIssue,
-    int depth = 0);
-
-[[nodiscard]] inline bool
-isAnyFrozen(
-    ReadView const& view,
-    std::initializer_list<AccountID> const& accounts,
-    Issue const& issue)
-{
-    for (auto const& account : accounts)
-    {
-        if (isFrozen(view, account, issue.currency, issue.account))
-            return true;
-    }
-    return false;
-}
-
-[[nodiscard]] inline bool
-isAnyFrozen(
-    ReadView const& view,
-    std::initializer_list<AccountID> const& accounts,
-    Asset const& asset,
-    int depth = 0)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) {
-            if constexpr (std::is_same_v<TIss, Issue>)
-                return isAnyFrozen(view, accounts, issue);
-            else
-                return isAnyFrozen(view, accounts, issue, depth);
-        },
-        asset.value());
-}
-
-[[nodiscard]] bool
-isDeepFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer);
-
-[[nodiscard]] inline bool
-isDeepFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    Issue const& issue,
-    int = 0 /*ignored*/)
-{
-    return isDeepFrozen(view, account, issue.currency, issue.account);
-}
-
-[[nodiscard]] inline bool
-isDeepFrozen(
-    ReadView const& view,
-    AccountID const& account,
-    MPTIssue const& mptIssue,
-    int depth = 0)
-{
-    // Unlike IOUs, frozen / locked MPTs are not allowed to send or receive
-    // funds, so checking "deep frozen" is the same as checking "frozen".
-    return isFrozen(view, account, mptIssue, depth);
-}
-
-/**
- *   isFrozen check is recursive for MPT shares in a vault, descending to
- *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
- *   purely defensive, as we currently do not allow such vaults to be created.
- */
-[[nodiscard]] inline bool
-isDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0)
-{
-    return std::visit(
-        [&](auto const& issue) { return isDeepFrozen(view, account, issue, depth); },
-        asset.value());
-}
-
-[[nodiscard]] inline TER
-checkDeepFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
-{
-    return isDeepFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkDeepFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue)
-{
-    return isDeepFrozen(view, account, mptIssue) ? (TER)tecLOCKED : (TER)tesSUCCESS;
-}
-
-[[nodiscard]] inline TER
-checkDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset)
-{
-    return std::visit(
-        [&](auto const& issue) { return checkDeepFrozen(view, account, issue); }, asset.value());
-}
-
 [[nodiscard]] bool
 isLPTokenFrozen(
     ReadView const& view,
@@ -256,159 +66,6 @@ isLPTokenFrozen(
     Issue const& asset,
     Issue const& asset2);
 
-// Returns the amount an account can spend.
-//
-// If shSIMPLE_BALANCE is specified, this is the amount the account can spend
-// without going into debt.
-//
-// If shFULL_BALANCE is specified, this is the amount the account can spend
-// total. Specifically:
-// * The account can go into debt if using a trust line, and the other side has
-// a non-zero limit.
-// * If the account is the asset issuer the limit is defined by the asset /
-//   issuance.
-//
-// <-- saAmount: amount of currency held by account. May be negative.
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    Currency const& currency,
-    AccountID const& issuer,
-    FreezeHandling zeroIfFrozen,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    Issue const& issue,
-    FreezeHandling zeroIfFrozen,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    MPTIssue const& mptIssue,
-    FreezeHandling zeroIfFrozen,
-    AuthHandling zeroIfUnauthorized,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-[[nodiscard]] STAmount
-accountHolds(
-    ReadView const& view,
-    AccountID const& account,
-    Asset const& asset,
-    FreezeHandling zeroIfFrozen,
-    AuthHandling zeroIfUnauthorized,
-    beast::Journal j,
-    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
-
-// Returns the amount an account can spend of the currency type saDefault, or
-// returns saDefault if this account is the issuer of the currency in
-// question. Should be used in favor of accountHolds when questioning how much
-// an account can spend while also allowing currency issuers to spend
-// unlimited amounts of their own currency (since they can always issue more).
-[[nodiscard]] STAmount
-accountFunds(
-    ReadView const& view,
-    AccountID const& id,
-    STAmount const& saDefault,
-    FreezeHandling freezeHandling,
-    beast::Journal j);
-
-// Return the account's liquid (not reserved) XRP.  Generally prefer
-// calling accountHolds() over this interface.  However, this interface
-// allows the caller to temporarily adjust the owner count should that be
-// necessary.
-//
-// @param ownerCountAdj positive to add to count, negative to reduce count.
-[[nodiscard]] XRPAmount
-xrpLiquid(ReadView const& view, AccountID const& id, std::int32_t ownerCountAdj, beast::Journal j);
-
-/** Iterate all items in the given directory. */
-void
-forEachItem(
-    ReadView const& view,
-    Keylet const& root,
-    std::function<void(std::shared_ptr<SLE const> const&)> const& f);
-
-/** Iterate all items after an item in the given directory.
-    @param after The key of the item to start after
-    @param hint The directory page containing `after`
-    @param limit The maximum number of items to return
-    @return `false` if the iteration failed
-*/
-bool
-forEachItemAfter(
-    ReadView const& view,
-    Keylet const& root,
-    uint256 const& after,
-    std::uint64_t const hint,
-    unsigned int limit,
-    std::function<bool(std::shared_ptr<SLE const> const&)> const& f);
-
-/** Iterate all items in an account's owner directory. */
-inline void
-forEachItem(
-    ReadView const& view,
-    AccountID const& id,
-    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
-{
-    return forEachItem(view, keylet::ownerDir(id), f);
-}
-
-/** Iterate all items after an item in an owner directory.
-    @param after The key of the item to start after
-    @param hint The directory page containing `after`
-    @param limit The maximum number of items to return
-    @return `false` if the iteration failed
-*/
-inline bool
-forEachItemAfter(
-    ReadView const& view,
-    AccountID const& id,
-    uint256 const& after,
-    std::uint64_t const hint,
-    unsigned int limit,
-    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
-{
-    return forEachItemAfter(view, keylet::ownerDir(id), after, hint, limit, f);
-}
-
-/** Returns IOU issuer transfer fee as Rate. Rate specifies
- * the fee as fractions of 1 billion. For example, 1% transfer rate
- * is represented as 1,010,000,000.
- * @param issuer The IOU issuer
- */
-[[nodiscard]] Rate
-transferRate(ReadView const& view, AccountID const& issuer);
-
-/** Returns MPT transfer fee as Rate. Rate specifies
- * the fee as fractions of 1 billion. For example, 1% transfer rate
- * is represented as 1,010,000,000.
- * @param issuanceID MPTokenIssuanceID of MPTTokenIssuance object
- */
-[[nodiscard]] Rate
-transferRate(ReadView const& view, MPTID const& issuanceID);
-
-/** Returns the transfer fee as Rate based on the type of token
- * @param view The ledger view
- * @param amount The amount to transfer
- */
-[[nodiscard]] Rate
-transferRate(ReadView const& view, STAmount const& amount);
-
-/** Returns `true` if the directory is empty
-    @param key The key of the directory
-*/
-[[nodiscard]] bool
-dirIsEmpty(ReadView const& view, Keylet const& k);
-
 // Return the list of enabled amendments
 [[nodiscard]] std::set<uint256>
 getEnabledAmendments(ReadView const& view);
@@ -474,81 +131,6 @@ areCompatible(
 //
 //------------------------------------------------------------------------------
 
-/** Adjust the owner count up or down. */
-void
-adjustOwnerCount(
-    ApplyView& view,
-    std::shared_ptr<SLE> const& sle,
-    std::int32_t amount,
-    beast::Journal j);
-
-/** @{ */
-/** Returns the first entry in the directory, advancing the index
-
-    @deprecated These are legacy function that are considered deprecated
-                and will soon be replaced with an iterator-based model
-                that is easier to use. You should not use them in new code.
-
-    @param view The view against which to operate
-    @param root The root (i.e. first page) of the directory to iterate
-    @param page The current page
-    @param index The index inside the current page
-    @param entry The entry at the current index
-
-    @return true if the directory isn't empty; false otherwise
- */
-bool
-cdirFirst(
-    ReadView const& view,
-    uint256 const& root,
-    std::shared_ptr<SLE const>& page,
-    unsigned int& index,
-    uint256& entry);
-
-bool
-dirFirst(
-    ApplyView& view,
-    uint256 const& root,
-    std::shared_ptr<SLE>& page,
-    unsigned int& index,
-    uint256& entry);
-/** @} */
-
-/** @{ */
-/** Returns the next entry in the directory, advancing the index
-
-    @deprecated These are legacy function that are considered deprecated
-                and will soon be replaced with an iterator-based model
-                that is easier to use. You should not use them in new code.
-
-    @param view The view against which to operate
-    @param root The root (i.e. first page) of the directory to iterate
-    @param page The current page
-    @param index The index inside the current page
-    @param entry The entry at the current index
-
-    @return true if the directory isn't empty; false otherwise
- */
-bool
-cdirNext(
-    ReadView const& view,
-    uint256 const& root,
-    std::shared_ptr<SLE const>& page,
-    unsigned int& index,
-    uint256& entry);
-
-bool
-dirNext(
-    ApplyView& view,
-    uint256 const& root,
-    std::shared_ptr<SLE>& page,
-    unsigned int& index,
-    uint256& entry);
-/** @} */
-
-[[nodiscard]] std::function<void(SLE::ref)>
-describeOwnerDir(AccountID const& account);
-
 [[nodiscard]] TER
 dirLink(
     ApplyView& view,
@@ -556,63 +138,6 @@ dirLink(
     std::shared_ptr<SLE>& object,
     SF_UINT64 const& node = sfOwnerNode);
 
-AccountID
-pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey);
-
-/**
- *
- * Create pseudo-account, storing pseudoOwnerKey into ownerField.
- *
- * The list of valid ownerField is maintained in View.cpp and the caller to
- * this function must perform necessary amendment check(s) before using a
- * field. The amendment check is **not** performed in createPseudoAccount.
- */
-[[nodiscard]] Expected<std::shared_ptr<SLE>, TER>
-createPseudoAccount(ApplyView& view, uint256 const& pseudoOwnerKey, SField const& ownerField);
-
-// Returns true if and only if sleAcct is a pseudo-account or specific
-// pseudo-accounts in pseudoFieldFilter.
-//
-// Returns false if sleAcct is
-// * NOT a pseudo-account OR
-// * NOT a ltACCOUNT_ROOT OR
-// * null pointer
-[[nodiscard]] bool
-isPseudoAccount(
-    std::shared_ptr<SLE const> sleAcct,
-    std::set<SField const*> const& pseudoFieldFilter = {});
-
-// Returns the list of fields that define an ACCOUNT_ROOT as a pseudo-account if
-// set
-// Pseudo-account designator fields MUST be maintained by including the
-// SField::sMD_PseudoAccount flag in the SField definition. (Don't forget to
-// "| SField::sMD_Default"!) The fields do NOT need to be amendment-gated,
-// since a non-active amendment will not set any field, by definition.
-// Specific properties of a pseudo-account are NOT checked here, that's what
-// InvariantCheck is for.
-[[nodiscard]] std::vector<SField const*> const&
-getPseudoAccountFields();
-
-[[nodiscard]] inline bool
-isPseudoAccount(
-    ReadView const& view,
-    AccountID const& accountId,
-    std::set<SField const*> const& pseudoFieldFilter = {})
-{
-    return isPseudoAccount(view.read(keylet::account(accountId)), pseudoFieldFilter);
-}
-
-[[nodiscard]] TER
-canAddHolding(ReadView const& view, Asset const& asset);
-
-/** Validates that the destination SLE and tag are valid
-
-   - Checks that the SLE is not null.
-   - If the SLE requires a destination tag, checks that there is a tag.
-*/
-[[nodiscard]] TER
-checkDestinationAndTag(SLE::const_ref toSle, bool hasDestinationTag);
-
 /** Checks that can withdraw funds from an object to itself or a destination.
  *
  * The receiver may be either the submitting account (sfAccount) or a different
@@ -686,351 +211,6 @@ doWithdraw(
     STAmount const& amount,
     beast::Journal j);
 
-/// Any transactors that call addEmptyHolding() in doApply must call
-/// canAddHolding() in preflight with the same View and Asset
-[[nodiscard]] TER
-addEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    XRPAmount priorBalance,
-    Issue const& issue,
-    beast::Journal journal);
-
-[[nodiscard]] TER
-addEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    XRPAmount priorBalance,
-    MPTIssue const& mptIssue,
-    beast::Journal journal);
-
-[[nodiscard]] inline TER
-addEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    XRPAmount priorBalance,
-    Asset const& asset,
-    beast::Journal journal)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
-            return addEmptyHolding(view, accountID, priorBalance, issue, journal);
-        },
-        asset.value());
-}
-
-[[nodiscard]] TER
-authorizeMPToken(
-    ApplyView& view,
-    XRPAmount const& priorBalance,
-    MPTID const& mptIssuanceID,
-    AccountID const& account,
-    beast::Journal journal,
-    std::uint32_t flags = 0,
-    std::optional<AccountID> holderID = std::nullopt);
-
-// VFALCO NOTE Both STAmount parameters should just
-//             be "Amount", a unit-less number.
-//
-/** Create a trust line
-
-    This can set an initial balance.
-*/
-[[nodiscard]] TER
-trustCreate(
-    ApplyView& view,
-    bool const bSrcHigh,
-    AccountID const& uSrcAccountID,
-    AccountID const& uDstAccountID,
-    uint256 const& uIndex,      // --> ripple state entry
-    SLE::ref sleAccount,        // --> the account being set.
-    bool const bAuth,           // --> authorize account.
-    bool const bNoRipple,       // --> others cannot ripple through
-    bool const bFreeze,         // --> funds cannot leave
-    bool bDeepFreeze,           // --> can neither receive nor send funds
-    STAmount const& saBalance,  // --> balance of account being set.
-                                // Issuer should be noAccount()
-    STAmount const& saLimit,    // --> limit for account being set.
-                                // Issuer should be the account being set.
-    std::uint32_t uSrcQualityIn,
-    std::uint32_t uSrcQualityOut,
-    beast::Journal j);
-
-[[nodiscard]] TER
-removeEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    Issue const& issue,
-    beast::Journal journal);
-
-[[nodiscard]] TER
-removeEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    MPTIssue const& mptIssue,
-    beast::Journal journal);
-
-[[nodiscard]] inline TER
-removeEmptyHolding(
-    ApplyView& view,
-    AccountID const& accountID,
-    Asset const& asset,
-    beast::Journal journal)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
-            return removeEmptyHolding(view, accountID, issue, journal);
-        },
-        asset.value());
-}
-
-[[nodiscard]] TER
-trustDelete(
-    ApplyView& view,
-    std::shared_ptr<SLE> const& sleRippleState,
-    AccountID const& uLowAccountID,
-    AccountID const& uHighAccountID,
-    beast::Journal j);
-
-/** Delete an offer.
-
-    Requirements:
-        The passed `sle` be obtained from a prior
-        call to view.peek()
-*/
-// [[nodiscard]] // nodiscard commented out so Flow, BookTip and others compile.
-TER
-offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j);
-
-//------------------------------------------------------------------------------
-
-//
-// Money Transfers
-//
-
-// Direct send w/o fees:
-// - Redeeming IOUs and/or sending sender's own IOUs.
-// - Create trust line of needed.
-// --> bCheckIssuer : normally require issuer to be involved.
-// [[nodiscard]] // nodiscard commented out so DirectStep.cpp compiles.
-
-/** Calls static rippleCreditIOU if saAmount represents Issue.
- * Calls static rippleCreditMPT if saAmount represents MPTIssue.
- */
-TER
-rippleCredit(
-    ApplyView& view,
-    AccountID const& uSenderID,
-    AccountID const& uReceiverID,
-    STAmount const& saAmount,
-    bool bCheckIssuer,
-    beast::Journal j);
-
-TER
-rippleLockEscrowMPT(
-    ApplyView& view,
-    AccountID const& uGrantorID,
-    STAmount const& saAmount,
-    beast::Journal j);
-
-TER
-rippleUnlockEscrowMPT(
-    ApplyView& view,
-    AccountID const& uGrantorID,
-    AccountID const& uGranteeID,
-    STAmount const& netAmount,
-    STAmount const& grossAmount,
-    beast::Journal j);
-
-/** Calls static accountSendIOU if saAmount represents Issue.
- * Calls static accountSendMPT if saAmount represents MPTIssue.
- */
-[[nodiscard]] TER
-accountSend(
-    ApplyView& view,
-    AccountID const& from,
-    AccountID const& to,
-    STAmount const& saAmount,
-    beast::Journal j,
-    WaiveTransferFee waiveFee = WaiveTransferFee::No);
-
-using MultiplePaymentDestinations = std::vector<std::pair<AccountID, Number>>;
-/** Like accountSend, except one account is sending multiple payments (with the
- *  same asset!) simultaneously
- *
- * Calls static accountSendMultiIOU if saAmount represents Issue.
- * Calls static accountSendMultiMPT if saAmount represents MPTIssue.
- */
-[[nodiscard]] TER
-accountSendMulti(
-    ApplyView& view,
-    AccountID const& senderID,
-    Asset const& asset,
-    MultiplePaymentDestinations const& receivers,
-    beast::Journal j,
-    WaiveTransferFee waiveFee = WaiveTransferFee::No);
-
-[[nodiscard]] TER
-issueIOU(
-    ApplyView& view,
-    AccountID const& account,
-    STAmount const& amount,
-    Issue const& issue,
-    beast::Journal j);
-
-[[nodiscard]] TER
-redeemIOU(
-    ApplyView& view,
-    AccountID const& account,
-    STAmount const& amount,
-    Issue const& issue,
-    beast::Journal j);
-
-[[nodiscard]] TER
-transferXRP(
-    ApplyView& view,
-    AccountID const& from,
-    AccountID const& to,
-    STAmount const& amount,
-    beast::Journal j);
-
-/* Check if MPToken (for MPT) or trust line (for IOU) exists:
- * - StrongAuth - before checking if authorization is required
- * - WeakAuth
- *    for MPT - after checking lsfMPTRequireAuth flag
- *    for IOU - do not check if trust line exists
- * - Legacy
- *    for MPT - before checking lsfMPTRequireAuth flag i.e. same as StrongAuth
- *    for IOU - do not check if trust line exists i.e. same as WeakAuth
- */
-enum class AuthType { StrongAuth, WeakAuth, Legacy };
-
-/** Check if the account lacks required authorization.
- *
- * Return tecNO_AUTH or tecNO_LINE if it does
- * and tesSUCCESS otherwise.
- *
- * If StrongAuth then return tecNO_LINE if the RippleState doesn't exist. Return
- * tecNO_AUTH if lsfRequireAuth is set on the issuer's AccountRoot, and the
- * RippleState does exist, and the RippleState is not authorized.
- *
- * If WeakAuth then return tecNO_AUTH if lsfRequireAuth is set, and the
- * RippleState exists, and is not authorized. Return tecNO_LINE if
- * lsfRequireAuth is set and the RippleState doesn't exist. Consequently, if
- * WeakAuth and lsfRequireAuth is *not* set, this function will return
- * tesSUCCESS even if RippleState does *not* exist.
- *
- * The default "Legacy" auth type is equivalent to WeakAuth.
- */
-[[nodiscard]] TER
-requireAuth(
-    ReadView const& view,
-    Issue const& issue,
-    AccountID const& account,
-    AuthType authType = AuthType::Legacy);
-
-/** Check if the account lacks required authorization.
- *
- * This will also check for expired credentials. If it is called directly
- * from preclaim, the user should convert result tecEXPIRED to tesSUCCESS and
- * proceed to also check permissions with enforceMPTokenAuthorization inside
- * doApply. This will ensure that any expired credentials are deleted.
- *
- * requireAuth check is recursive for MPT shares in a vault, descending to
- * assets in the vault, up to maxAssetCheckDepth recursion depth. This is
- * purely defensive, as we currently do not allow such vaults to be created.
- *
- * If StrongAuth then return tecNO_AUTH if MPToken doesn't exist or
- * lsfMPTRequireAuth is set and MPToken is not authorized. Vault and LoanBroker
- * pseudo-accounts are implicitly authorized.
- *
- * If WeakAuth then return tecNO_AUTH if lsfMPTRequireAuth is set and MPToken
- * doesn't exist or is not authorized (explicitly or via credentials, if
- * DomainID is set in MPTokenIssuance). Consequently, if WeakAuth and
- * lsfMPTRequireAuth is *not* set, this function will return true even if
- * MPToken does *not* exist.
- *
- * The default "Legacy" auth type is equivalent to StrongAuth.
- */
-[[nodiscard]] TER
-requireAuth(
-    ReadView const& view,
-    MPTIssue const& mptIssue,
-    AccountID const& account,
-    AuthType authType = AuthType::Legacy,
-    int depth = 0);
-
-[[nodiscard]] TER inline requireAuth(
-    ReadView const& view,
-    Asset const& asset,
-    AccountID const& account,
-    AuthType authType = AuthType::Legacy)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue_) {
-            return requireAuth(view, issue_, account, authType);
-        },
-        asset.value());
-}
-
-/** Enforce account has MPToken to match its authorization.
- *
- *   Called from doApply - it will check for expired (and delete if found any)
- *   credentials matching DomainID set in MPTokenIssuance. Must be called if
- *   requireAuth(...MPTIssue...) returned tesSUCCESS or tecEXPIRED in preclaim,
- *   which implies that preclaim should replace `tecEXPIRED` with `tesSUCCESS`
- *   in order for the transactor to proceed to doApply.
- *
- *   This function will create MPToken (if needed) on the basis of any
- *   non-expired credentials and will delete any expired credentials, indirectly
- *   via verifyValidDomain, as per DomainID (if set in MPTokenIssuance).
- *
- *   The caller does NOT need to ensure that DomainID is actually set - this
- *   function handles gracefully both cases when DomainID is set and when not.
- *
- *   The caller does NOT need to look for existing MPToken to match
- *   mptIssue/account - this function checks lsfMPTAuthorized of an existing
- *   MPToken iff DomainID is not set.
- *
- *   Do not use for accounts which hold implied permission e.g. object owners or
- *   if MPTokenIssuance does not require authorization. In both cases use
- *   MPTokenAuthorize::authorize if MPToken does not yet exist.
- */
-[[nodiscard]] TER
-enforceMPTokenAuthorization(
-    ApplyView& view,
-    MPTID const& mptIssuanceID,
-    AccountID const& account,
-    XRPAmount const& priorBalance,
-    beast::Journal j);
-
-/** Check if the destination account is allowed
- *  to receive MPT. Return tecNO_AUTH if it doesn't
- *  and tesSUCCESS otherwise.
- */
-[[nodiscard]] TER
-canTransfer(
-    ReadView const& view,
-    MPTIssue const& mptIssue,
-    AccountID const& from,
-    AccountID const& to);
-
-[[nodiscard]] TER
-canTransfer(ReadView const& view, Issue const& issue, AccountID const& from, AccountID const& to);
-
-[[nodiscard]] TER inline canTransfer(
-    ReadView const& view,
-    Asset const& asset,
-    AccountID const& from,
-    AccountID const& to)
-{
-    return std::visit(
-        [&]<ValidIssueType TIss>(TIss const& issue) -> TER {
-            return canTransfer(view, issue, from, to);
-        },
-        asset.value());
-}
-
 /** Deleter function prototype. Returns the status of the entry deletion
  * (if should not be skipped) and if the entry should be skipped. The status
  * is always tesSUCCESS if the entry should be skipped.
@@ -1052,57 +232,6 @@ cleanupOnAccountDelete(
     beast::Journal j,
     std::optional<std::uint16_t> maxNodesToDelete = std::nullopt);
 
-/** Delete trustline to AMM. The passed `sle` must be obtained from a prior
- * call to view.peek(). Fail if neither side of the trustline is AMM or
- * if ammAccountID is seated and is not one of the trustline's side.
- */
-[[nodiscard]] TER
-deleteAMMTrustLine(
-    ApplyView& view,
-    std::shared_ptr<SLE> sleState,
-    std::optional<AccountID> const& ammAccountID,
-    beast::Journal j);
-
-// From the perspective of a vault, return the number of shares to give the
-// depositor when they deposit a fixed amount of assets. Since shares are MPT
-// this number is integral and always truncated in this calculation.
-[[nodiscard]] std::optional<STAmount>
-assetsToSharesDeposit(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& assets);
-
-// From the perspective of a vault, return the number of assets to take from
-// depositor when they receive a fixed amount of shares. Note, since shares are
-// MPT, they are always an integral number.
-[[nodiscard]] std::optional<STAmount>
-sharesToAssetsDeposit(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& shares);
-
-enum class TruncateShares : bool { no = false, yes = true };
-
-// From the perspective of a vault, return the number of shares to demand from
-// the depositor when they ask to withdraw a fixed amount of assets. Since
-// shares are MPT this number is integral, and it will be rounded to nearest
-// unless explicitly requested to be truncated instead.
-[[nodiscard]] std::optional<STAmount>
-assetsToSharesWithdraw(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& assets,
-    TruncateShares truncate = TruncateShares::no);
-
-// From the perspective of a vault, return the number of assets to give the
-// depositor when they redeem a fixed amount of shares. Note, since shares are
-// MPT, they are always an integral number.
-[[nodiscard]] std::optional<STAmount>
-sharesToAssetsWithdraw(
-    std::shared_ptr<SLE const> const& vault,
-    std::shared_ptr<SLE const> const& issuance,
-    STAmount const& shares);
-
 /** Has the specified time passed?
 
     @param now  the current time

include/xrpl/ledger/helpers/AccountRootHelpers.h

@@ -0,0 +1,112 @@
+#pragma once
+
+#include <xrpl/basics/Expected.h>
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Rate.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <memory>
+#include <set>
+#include <vector>
+
+namespace xrpl {
+
+/** Check if the issuer has the global freeze flag set.
+    @param issuer The account to check
+    @return true if the account has global freeze set
+*/
+[[nodiscard]] bool
+isGlobalFrozen(ReadView const& view, AccountID const& issuer);
+
+// Calculate liquid XRP balance for an account.
+// This function may be used to calculate the amount of XRP that
+// the holder is able to freely spend. It subtracts reserve requirements.
+//
+// ownerCountAdj adjusts the owner count in case the caller calculates
+// before ledger entries are added or removed. Positive to add, negative
+// to subtract.
+//
+// @param ownerCountAdj positive to add to count, negative to reduce count.
+[[nodiscard]] XRPAmount
+xrpLiquid(ReadView const& view, AccountID const& id, std::int32_t ownerCountAdj, beast::Journal j);
+
+/** Adjust the owner count up or down. */
+void
+adjustOwnerCount(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sle,
+    std::int32_t amount,
+    beast::Journal j);
+
+/** Returns IOU issuer transfer fee as Rate. Rate specifies
+ * the fee as fractions of 1 billion. For example, 1% transfer rate
+ * is represented as 1,010,000,000.
+ * @param issuer The IOU issuer
+ */
+[[nodiscard]] Rate
+transferRate(ReadView const& view, AccountID const& issuer);
+
+/** Generate a pseudo-account address from a pseudo owner key.
+    @param pseudoOwnerKey The key to generate the address from
+    @return The generated account ID
+*/
+AccountID
+pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey);
+
+/** Returns the list of fields that define an ACCOUNT_ROOT as a pseudo-account
+    if set.
+
+    The list is constructed during initialization and is const after that.
+    Pseudo-account designator fields MUST be maintained by including the
+    SField::sMD_PseudoAccount flag in the SField definition.
+*/
+[[nodiscard]] std::vector<SField const*> const&
+getPseudoAccountFields();
+
+/** Returns true if and only if sleAcct is a pseudo-account or specific
+    pseudo-accounts in pseudoFieldFilter.
+
+    Returns false if sleAcct is:
+    - NOT a pseudo-account OR
+    - NOT a ltACCOUNT_ROOT OR
+    - null pointer
+*/
+[[nodiscard]] bool
+isPseudoAccount(
+    std::shared_ptr<SLE const> sleAcct,
+    std::set<SField const*> const& pseudoFieldFilter = {});
+
+/** Convenience overload that reads the account from the view. */
+[[nodiscard]] inline bool
+isPseudoAccount(
+    ReadView const& view,
+    AccountID const& accountId,
+    std::set<SField const*> const& pseudoFieldFilter = {})
+{
+    return isPseudoAccount(view.read(keylet::account(accountId)), pseudoFieldFilter);
+}
+
+/**
+ * Create pseudo-account, storing pseudoOwnerKey into ownerField.
+ *
+ * The list of valid ownerField is maintained in AccountRootHelpers.cpp and
+ * the caller to this function must perform necessary amendment check(s)
+ * before using a field. The amendment check is **not** performed in
+ * createPseudoAccount.
+ */
+[[nodiscard]] Expected<std::shared_ptr<SLE>, TER>
+createPseudoAccount(ApplyView& view, uint256 const& pseudoOwnerKey, SField const& ownerField);
+
+/** Checks the destination and tag.
+
+   - Checks that the SLE is not null.
+   - If the SLE requires a destination tag, checks that there is a tag.
+*/
+[[nodiscard]] TER
+checkDestinationAndTag(SLE::const_ref toSle, bool hasDestinationTag);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/DirectoryHelpers.h

@@ -0,0 +1,223 @@
+#pragma once
+
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <functional>
+#include <memory>
+#include <type_traits>
+
+namespace xrpl {
+
+namespace detail {
+
+template <
+    class V,
+    class N,
+    class = std::enable_if_t<
+        std::is_same_v<std::remove_cv_t<N>, SLE> && std::is_base_of_v<ReadView, V>>>
+bool
+internalDirNext(
+    V& view,
+    uint256 const& root,
+    std::shared_ptr<N>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    auto const& svIndexes = page->getFieldV256(sfIndexes);
+    XRPL_ASSERT(index <= svIndexes.size(), "xrpl::detail::internalDirNext : index inside range");
+
+    if (index >= svIndexes.size())
+    {
+        auto const next = page->getFieldU64(sfIndexNext);
+
+        if (!next)
+        {
+            entry.zero();
+            return false;
+        }
+
+        if constexpr (std::is_const_v<N>)
+        {
+            page = view.read(keylet::page(root, next));
+        }
+        else
+        {
+            page = view.peek(keylet::page(root, next));
+        }
+
+        XRPL_ASSERT(page, "xrpl::detail::internalDirNext : non-null root");
+
+        if (!page)
+            return false;
+
+        index = 0;
+
+        return internalDirNext(view, root, page, index, entry);
+    }
+
+    entry = svIndexes[index++];
+    return true;
+}
+
+template <
+    class V,
+    class N,
+    class = std::enable_if_t<
+        std::is_same_v<std::remove_cv_t<N>, SLE> && std::is_base_of_v<ReadView, V>>>
+bool
+internalDirFirst(
+    V& view,
+    uint256 const& root,
+    std::shared_ptr<N>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    if constexpr (std::is_const_v<N>)
+    {
+        page = view.read(keylet::page(root));
+    }
+    else
+    {
+        page = view.peek(keylet::page(root));
+    }
+
+    if (!page)
+        return false;
+
+    index = 0;
+
+    return internalDirNext(view, root, page, index, entry);
+}
+
+}  // namespace detail
+
+/** @{ */
+/** Returns the first entry in the directory, advancing the index
+
+    @deprecated These are legacy function that are considered deprecated
+                and will soon be replaced with an iterator-based model
+                that is easier to use. You should not use them in new code.
+
+    @param view The view against which to operate
+    @param root The root (i.e. first page) of the directory to iterate
+    @param page The current page
+    @param index The index inside the current page
+    @param entry The entry at the current index
+
+    @return true if the directory isn't empty; false otherwise
+ */
+bool
+cdirFirst(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry);
+
+bool
+dirFirst(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry);
+/** @} */
+
+/** @{ */
+/** Returns the next entry in the directory, advancing the index
+
+    @deprecated These are legacy function that are considered deprecated
+                and will soon be replaced with an iterator-based model
+                that is easier to use. You should not use them in new code.
+
+    @param view The view against which to operate
+    @param root The root (i.e. first page) of the directory to iterate
+    @param page The current page
+    @param index The index inside the current page
+    @param entry The entry at the current index
+
+    @return true if the directory isn't empty; false otherwise
+ */
+bool
+cdirNext(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry);
+
+bool
+dirNext(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry);
+/** @} */
+
+/** Iterate all items in the given directory. */
+void
+forEachItem(
+    ReadView const& view,
+    Keylet const& root,
+    std::function<void(std::shared_ptr<SLE const> const&)> const& f);
+
+/** Iterate all items after an item in the given directory.
+    @param after The key of the item to start after
+    @param hint The directory page containing `after`
+    @param limit The maximum number of items to return
+    @return `false` if the iteration failed
+*/
+bool
+forEachItemAfter(
+    ReadView const& view,
+    Keylet const& root,
+    uint256 const& after,
+    std::uint64_t const hint,
+    unsigned int limit,
+    std::function<bool(std::shared_ptr<SLE const> const&)> const& f);
+
+/** Iterate all items in an account's owner directory. */
+inline void
+forEachItem(
+    ReadView const& view,
+    AccountID const& id,
+    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
+{
+    return forEachItem(view, keylet::ownerDir(id), f);
+}
+
+/** Iterate all items after an item in an owner directory.
+    @param after The key of the item to start after
+    @param hint The directory page containing `after`
+    @param limit The maximum number of items to return
+    @return `false` if the iteration failed
+*/
+inline bool
+forEachItemAfter(
+    ReadView const& view,
+    AccountID const& id,
+    uint256 const& after,
+    std::uint64_t const hint,
+    unsigned int limit,
+    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
+{
+    return forEachItemAfter(view, keylet::ownerDir(id), after, hint, limit, f);
+}
+
+/** Returns `true` if the directory is empty
+    @param key The key of the directory
+*/
+[[nodiscard]] bool
+dirIsEmpty(ReadView const& view, Keylet const& k);
+
+/** Returns a function that sets the owner on a directory SLE */
+[[nodiscard]] std::function<void(SLE::ref)>
+describeOwnerDir(AccountID const& account);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/MPTokenHelpers.h

@@ -0,0 +1,160 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
+#include <xrpl/protocol/MPTIssue.h>
+#include <xrpl/protocol/Rate.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/TER.h>
+
+#include <initializer_list>
+#include <optional>
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] bool
+isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue);
+
+[[nodiscard]] bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
+
+[[nodiscard]] bool
+isFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue, int depth = 0);
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    MPTIssue const& mptIssue,
+    int depth = 0);
+
+//------------------------------------------------------------------------------
+//
+// Transfer rate (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+/** Returns MPT transfer fee as Rate. Rate specifies
+ * the fee as fractions of 1 billion. For example, 1% transfer rate
+ * is represented as 1,010,000,000.
+ * @param issuanceID MPTokenIssuanceID of MPTTokenIssuance object
+ */
+[[nodiscard]] Rate
+transferRate(ReadView const& view, MPTID const& issuanceID);
+
+//------------------------------------------------------------------------------
+//
+// Holding checks (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+canAddHolding(ReadView const& view, MPTIssue const& mptIssue);
+
+//------------------------------------------------------------------------------
+//
+// Authorization (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+authorizeMPToken(
+    ApplyView& view,
+    XRPAmount const& priorBalance,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    beast::Journal journal,
+    std::uint32_t flags = 0,
+    std::optional<AccountID> holderID = std::nullopt);
+
+/** Check if the account lacks required authorization for MPT.
+ *
+ * requireAuth check is recursive for MPT shares in a vault, descending to
+ * assets in the vault, up to maxAssetCheckDepth recursion depth. This is
+ * purely defensive, as we currently do not allow such vaults to be created.
+ */
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& account,
+    AuthType authType = AuthType::Legacy,
+    int depth = 0);
+
+/** Enforce account has MPToken to match its authorization.
+ *
+ *   Called from doApply - it will check for expired (and delete if found any)
+ *   credentials matching DomainID set in MPTokenIssuance. Must be called if
+ *   requireAuth(...MPTIssue...) returned tesSUCCESS or tecEXPIRED in preclaim.
+ */
+[[nodiscard]] TER
+enforceMPTokenAuthorization(
+    ApplyView& view,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    XRPAmount const& priorBalance,
+    beast::Journal j);
+
+/** Check if the destination account is allowed
+ *  to receive MPT. Return tecNO_AUTH if it doesn't
+ *  and tesSUCCESS otherwise.
+ */
+[[nodiscard]] TER
+canTransfer(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& from,
+    AccountID const& to);
+
+//------------------------------------------------------------------------------
+//
+// Empty holding operations (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    MPTIssue const& mptIssue,
+    beast::Journal journal);
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    MPTIssue const& mptIssue,
+    beast::Journal journal);
+
+//------------------------------------------------------------------------------
+//
+// Escrow operations (MPT-specific)
+//
+//------------------------------------------------------------------------------
+
+TER
+rippleLockEscrowMPT(
+    ApplyView& view,
+    AccountID const& uGrantorID,
+    STAmount const& saAmount,
+    beast::Journal j);
+
+TER
+rippleUnlockEscrowMPT(
+    ApplyView& view,
+    AccountID const& uGrantorID,
+    AccountID const& uGranteeID,
+    STAmount const& netAmount,
+    STAmount const& grossAmount,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/OfferHelpers.h

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+#include <memory>
+
+namespace xrpl {
+
+/** Delete an offer.
+
+    Requirements:
+        The offer must exist.
+        The caller must have already checked permissions.
+
+    @param view The ApplyView to modify.
+    @param sle The offer to delete.
+    @param j Journal for logging.
+
+    @return tesSUCCESS on success, otherwise an error code.
+*/
+// [[nodiscard]] // nodiscard commented out so Flow, BookTip and others compile.
+TER
+offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/RippleStateHelpers.h

@@ -0,0 +1,255 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
+#include <xrpl/protocol/IOUAmount.h>
+#include <xrpl/protocol/Issue.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/TER.h>
+
+//------------------------------------------------------------------------------
+//
+// RippleState (Trustline) helpers
+//
+//------------------------------------------------------------------------------
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Credit functions (from Credit.h)
+//
+//------------------------------------------------------------------------------
+
+/** Calculate the maximum amount of IOUs that an account can hold
+    @param view the ledger to check against.
+    @param account the account of interest.
+    @param issuer the issuer of the IOU.
+    @param currency the IOU to check.
+    @return The maximum amount that can be held.
+*/
+/** @{ */
+STAmount
+creditLimit(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency);
+
+IOUAmount
+creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur);
+/** @} */
+
+/** Returns the amount of IOUs issued by issuer that are held by an account
+    @param view the ledger to check against.
+    @param account the account of interest.
+    @param issuer the issuer of the IOU.
+    @param currency the IOU to check.
+*/
+/** @{ */
+STAmount
+creditBalance(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency);
+/** @} */
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] bool
+isIndividualFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer);
+
+[[nodiscard]] inline bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
+{
+    return isIndividualFrozen(view, account, issue.currency, issue.account);
+}
+
+[[nodiscard]] bool
+isFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer);
+
+[[nodiscard]] inline bool
+isFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
+{
+    return isFrozen(view, account, issue.currency, issue.account);
+}
+
+// Overload with depth parameter for uniformity with MPTIssue version.
+// The depth parameter is ignored for IOUs since they don't have vault recursion.
+[[nodiscard]] inline bool
+isFrozen(ReadView const& view, AccountID const& account, Issue const& issue, int /*depth*/)
+{
+    return isFrozen(view, account, issue);
+}
+
+[[nodiscard]] bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer);
+
+[[nodiscard]] inline bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Issue const& issue,
+    int = 0 /*ignored*/)
+{
+    return isDeepFrozen(view, account, issue.currency, issue.account);
+}
+
+[[nodiscard]] inline TER
+checkDeepFrozen(ReadView const& view, AccountID const& account, Issue const& issue)
+{
+    return isDeepFrozen(view, account, issue) ? (TER)tecFROZEN : (TER)tesSUCCESS;
+}
+
+//------------------------------------------------------------------------------
+//
+// Trust line operations
+//
+//------------------------------------------------------------------------------
+
+/** Create a trust line
+
+    This can set an initial balance.
+*/
+[[nodiscard]] TER
+trustCreate(
+    ApplyView& view,
+    bool const bSrcHigh,
+    AccountID const& uSrcAccountID,
+    AccountID const& uDstAccountID,
+    uint256 const& uIndex,      // --> ripple state entry
+    SLE::ref sleAccount,        // --> the account being set.
+    bool const bAuth,           // --> authorize account.
+    bool const bNoRipple,       // --> others cannot ripple through
+    bool const bFreeze,         // --> funds cannot leave
+    bool bDeepFreeze,           // --> can neither receive nor send funds
+    STAmount const& saBalance,  // --> balance of account being set.
+                                // Issuer should be noAccount()
+    STAmount const& saLimit,    // --> limit for account being set.
+                                // Issuer should be the account being set.
+    std::uint32_t uQualityIn,
+    std::uint32_t uQualityOut,
+    beast::Journal j);
+
+[[nodiscard]] TER
+trustDelete(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sleRippleState,
+    AccountID const& uLowAccountID,
+    AccountID const& uHighAccountID,
+    beast::Journal j);
+
+//------------------------------------------------------------------------------
+//
+// IOU issuance/redemption
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+issueIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j);
+
+[[nodiscard]] TER
+redeemIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j);
+
+//------------------------------------------------------------------------------
+//
+// Authorization and transfer checks (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+/** Check if the account lacks required authorization.
+ *
+ * Return tecNO_AUTH or tecNO_LINE if it does
+ * and tesSUCCESS otherwise.
+ *
+ * If StrongAuth then return tecNO_LINE if the RippleState doesn't exist. Return
+ * tecNO_AUTH if lsfRequireAuth is set on the issuer's AccountRoot, and the
+ * RippleState does exist, and the RippleState is not authorized.
+ *
+ * If WeakAuth then return tecNO_AUTH if lsfRequireAuth is set, and the
+ * RippleState exists, and is not authorized. Return tecNO_LINE if
+ * lsfRequireAuth is set and the RippleState doesn't exist. Consequently, if
+ * WeakAuth and lsfRequireAuth is *not* set, this function will return
+ * tesSUCCESS even if RippleState does *not* exist.
+ *
+ * The default "Legacy" auth type is equivalent to WeakAuth.
+ */
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    Issue const& issue,
+    AccountID const& account,
+    AuthType authType = AuthType::Legacy);
+
+/** Check if the destination account is allowed
+ *  to receive IOU. Return terNO_RIPPLE if rippling is
+ *  disabled on both sides and tesSUCCESS otherwise.
+ */
+[[nodiscard]] TER
+canTransfer(ReadView const& view, Issue const& issue, AccountID const& from, AccountID const& to);
+
+//------------------------------------------------------------------------------
+//
+// Empty holding operations (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+/// Any transactors that call addEmptyHolding() in doApply must call
+/// canAddHolding() in preflight with the same View and Asset
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    Issue const& issue,
+    beast::Journal journal);
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    Issue const& issue,
+    beast::Journal journal);
+
+/** Delete trustline to AMM. The passed `sle` must be obtained from a prior
+ * call to view.peek(). Fail if neither side of the trustline is AMM or
+ * if ammAccountID is seated and is not one of the trustline's side.
+ */
+[[nodiscard]] TER
+deleteAMMTrustLine(
+    ApplyView& view,
+    std::shared_ptr<SLE> sleState,
+    std::optional<AccountID> const& ammAccountID,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/TokenHelpers.h

@@ -0,0 +1,286 @@
+#pragma once
+
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/Asset.h>
+#include <xrpl/protocol/MPTIssue.h>
+#include <xrpl/protocol/Rate.h>
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/TER.h>
+
+#include <initializer_list>
+#include <vector>
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Enums for token handling
+//
+//------------------------------------------------------------------------------
+
+/** Controls the treatment of frozen account balances */
+enum FreezeHandling { fhIGNORE_FREEZE, fhZERO_IF_FROZEN };
+
+/** Controls the treatment of unauthorized MPT balances */
+enum AuthHandling { ahIGNORE_AUTH, ahZERO_IF_UNAUTHORIZED };
+
+/** Controls whether to include the account's full spendable balance */
+enum SpendableHandling { shSIMPLE_BALANCE, shFULL_BALANCE };
+
+enum class WaiveTransferFee : bool { No = false, Yes };
+
+/* Check if MPToken (for MPT) or trust line (for IOU) exists:
+ * - StrongAuth - before checking if authorization is required
+ * - WeakAuth
+ *    for MPT - after checking lsfMPTRequireAuth flag
+ *    for IOU - do not check if trust line exists
+ * - Legacy
+ *    for MPT - before checking lsfMPTRequireAuth flag i.e. same as StrongAuth
+ *    for IOU - do not check if trust line exists i.e. same as WeakAuth
+ */
+enum class AuthType { StrongAuth, WeakAuth, Legacy };
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] bool
+isGlobalFrozen(ReadView const& view, Asset const& asset);
+
+[[nodiscard]] bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, Asset const& asset);
+
+/**
+ *   isFrozen check is recursive for MPT shares in a vault, descending to
+ *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
+ *   purely defensive, as we currently do not allow such vaults to be created.
+ */
+[[nodiscard]] bool
+isFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0);
+
+[[nodiscard]] TER
+checkFrozen(ReadView const& view, AccountID const& account, Issue const& issue);
+
+[[nodiscard]] TER
+checkFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
+
+[[nodiscard]] TER
+checkFrozen(ReadView const& view, AccountID const& account, Asset const& asset);
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    Issue const& issue);
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    Asset const& asset,
+    int depth = 0);
+
+[[nodiscard]] bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    MPTIssue const& mptIssue,
+    int depth = 0);
+
+/**
+ *   isFrozen check is recursive for MPT shares in a vault, descending to
+ *   assets in the vault, up to maxAssetCheckDepth recursion depth. This is
+ *   purely defensive, as we currently do not allow such vaults to be created.
+ */
+[[nodiscard]] bool
+isDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset, int depth = 0);
+
+[[nodiscard]] TER
+checkDeepFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue);
+
+[[nodiscard]] TER
+checkDeepFrozen(ReadView const& view, AccountID const& account, Asset const& asset);
+
+//------------------------------------------------------------------------------
+//
+// Account balance functions (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+// Returns the amount an account can spend.
+//
+// If shSIMPLE_BALANCE is specified, this is the amount the account can spend
+// without going into debt.
+//
+// If shFULL_BALANCE is specified, this is the amount the account can spend
+// total. Specifically:
+// * The account can go into debt if using a trust line, and the other side has
+// a non-zero limit.
+// * If the account is the asset issuer the limit is defined by the asset /
+//   issuance.
+//
+// <-- saAmount: amount of currency held by account. May be negative.
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer,
+    FreezeHandling zeroIfFrozen,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    Issue const& issue,
+    FreezeHandling zeroIfFrozen,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    MPTIssue const& mptIssue,
+    FreezeHandling zeroIfFrozen,
+    AuthHandling zeroIfUnauthorized,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+[[nodiscard]] STAmount
+accountHolds(
+    ReadView const& view,
+    AccountID const& account,
+    Asset const& asset,
+    FreezeHandling zeroIfFrozen,
+    AuthHandling zeroIfUnauthorized,
+    beast::Journal j,
+    SpendableHandling includeFullBalance = shSIMPLE_BALANCE);
+
+// Returns the amount an account can spend of the currency type saDefault, or
+// returns saDefault if this account is the issuer of the currency in
+// question. Should be used in favor of accountHolds when questioning how much
+// an account can spend while also allowing currency issuers to spend
+// unlimited amounts of their own currency (since they can always issue more).
+[[nodiscard]] STAmount
+accountFunds(
+    ReadView const& view,
+    AccountID const& id,
+    STAmount const& saDefault,
+    FreezeHandling freezeHandling,
+    beast::Journal j);
+
+/** Returns the transfer fee as Rate based on the type of token
+ * @param view The ledger view
+ * @param amount The amount to transfer
+ */
+[[nodiscard]] Rate
+transferRate(ReadView const& view, STAmount const& amount);
+
+//------------------------------------------------------------------------------
+//
+// Holding operations (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+canAddHolding(ReadView const& view, Asset const& asset);
+
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    Asset const& asset,
+    beast::Journal journal);
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    Asset const& asset,
+    beast::Journal journal);
+
+//------------------------------------------------------------------------------
+//
+// Authorization and transfer checks (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    Asset const& asset,
+    AccountID const& account,
+    AuthType authType = AuthType::Legacy);
+
+[[nodiscard]] TER
+canTransfer(ReadView const& view, Asset const& asset, AccountID const& from, AccountID const& to);
+
+//------------------------------------------------------------------------------
+//
+// Money Transfers (Asset-based dispatchers)
+//
+//------------------------------------------------------------------------------
+
+// Direct send w/o fees:
+// - Redeeming IOUs and/or sending sender's own IOUs.
+// - Create trust line of needed.
+// --> bCheckIssuer : normally require issuer to be involved.
+// [[nodiscard]] // nodiscard commented out so DirectStep.cpp compiles.
+
+/** Calls static rippleCreditIOU if saAmount represents Issue.
+ * Calls static rippleCreditMPT if saAmount represents MPTIssue.
+ */
+TER
+rippleCredit(
+    ApplyView& view,
+    AccountID const& uSenderID,
+    AccountID const& uReceiverID,
+    STAmount const& saAmount,
+    bool bCheckIssuer,
+    beast::Journal j);
+
+/** Calls static accountSendIOU if saAmount represents Issue.
+ * Calls static accountSendMPT if saAmount represents MPTIssue.
+ */
+[[nodiscard]] TER
+accountSend(
+    ApplyView& view,
+    AccountID const& from,
+    AccountID const& to,
+    STAmount const& saAmount,
+    beast::Journal j,
+    WaiveTransferFee waiveFee = WaiveTransferFee::No);
+
+using MultiplePaymentDestinations = std::vector<std::pair<AccountID, Number>>;
+/** Like accountSend, except one account is sending multiple payments (with the
+ *  same asset!) simultaneously
+ *
+ * Calls static accountSendMultiIOU if saAmount represents Issue.
+ * Calls static accountSendMultiMPT if saAmount represents MPTIssue.
+ */
+[[nodiscard]] TER
+accountSendMulti(
+    ApplyView& view,
+    AccountID const& senderID,
+    Asset const& asset,
+    MultiplePaymentDestinations const& receivers,
+    beast::Journal j,
+    WaiveTransferFee waiveFee = WaiveTransferFee::No);
+
+[[nodiscard]] TER
+transferXRP(
+    ApplyView& view,
+    AccountID const& from,
+    AccountID const& to,
+    STAmount const& amount,
+    beast::Journal j);
+
+}  // namespace xrpl

include/xrpl/ledger/helpers/VaultHelpers.h

@@ -0,0 +1,81 @@
+#pragma once
+
+#include <xrpl/protocol/STAmount.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+
+#include <memory>
+#include <optional>
+
+namespace xrpl {
+
+/** From the perspective of a vault, return the number of shares to give
+    depositor when they offer a fixed amount of assets. Note, since shares are
+    MPT, this number is integral and always truncated in this calculation.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param assets The amount of assets to convert.
+
+    @return The number of shares, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets);
+
+/** From the perspective of a vault, return the number of assets to take from
+    depositor when they receive a fixed amount of shares. Note, since shares are
+    MPT, they are always an integral number.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param shares The amount of shares to convert.
+
+    @return The number of assets, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares);
+
+/** Controls whether to truncate shares instead of rounding. */
+enum class TruncateShares : bool { no = false, yes = true };
+
+/** From the perspective of a vault, return the number of shares to demand from
+    the depositor when they ask to withdraw a fixed amount of assets. Since
+    shares are MPT this number is integral, and it will be rounded to nearest
+    unless explicitly requested to be truncated instead.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param assets The amount of assets to convert.
+    @param truncate Whether to truncate instead of rounding.
+
+    @return The number of shares, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets,
+    TruncateShares truncate = TruncateShares::no);
+
+/** From the perspective of a vault, return the number of assets to give the
+    depositor when they redeem a fixed amount of shares. Note, since shares are
+    MPT, they are always an integral number.
+
+    @param vault The vault SLE.
+    @param issuance The MPTokenIssuance SLE for the vault's shares.
+    @param shares The amount of shares to convert.
+
+    @return The number of assets, or nullopt on error.
+*/
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares);
+
+}  // namespace xrpl

include/xrpl/protocol/Fees.h

@@ -4,6 +4,10 @@
 
 namespace xrpl {
 
+// Deprecated constant for backwards compatibility with pre-XRPFees amendment.
+// This was the reference fee units used in the old fee calculation.
+inline constexpr std::uint32_t FEE_UNITS_DEPRECATED = 10;
+
 /** Reflects the fee settings for a particular ledger.
 
     The fees are always the same for any transactions applied
@@ -11,15 +15,25 @@ namespace xrpl {
 */
 struct Fees
 {
-    XRPAmount base{0};       // Reference tx cost (drops)
-    XRPAmount reserve{0};    // Reserve base (drops)
-    XRPAmount increment{0};  // Reserve increment (drops)
+    /** @brief Cost of a reference transaction in drops. */
+    XRPAmount base{0};
+
+    /** @brief Minimum XRP an account must hold to exist on the ledger. */
+    XRPAmount reserve{0};
+
+    /** @brief Additional XRP reserve required per owned ledger object. */
+    XRPAmount increment{0};
 
     explicit Fees() = default;
     Fees(Fees const&) = default;
     Fees&
     operator=(Fees const&) = default;
 
+    Fees(XRPAmount base_, XRPAmount reserve_, XRPAmount increment_)
+        : base(base_), reserve(reserve_), increment(increment_)
+    {
+    }
+
     /** Returns the account reserve given the owner count, in drops.
 
         The reserve is calculated as the reserve base plus

include/xrpl/protocol/LedgerHeader.h

@@ -72,4 +72,8 @@ deserializeHeader(Slice data, bool hasHash = false);
 LedgerHeader
 deserializePrefixedHeader(Slice data, bool hasHash = false);
 
+/** Calculate the hash of a ledger header. */
+uint256
+calculateLedgerHash(LedgerHeader const& info);
+
 }  // namespace xrpl

include/xrpl/protocol/Permissions.h

@@ -72,12 +72,12 @@ public:
     isDelegable(std::uint32_t const& permissionValue, Rules const& rules) const;
 
     // for tx level permission, permission value is equal to tx type plus one
-    uint32_t
-    txToPermissionType(TxType const& type) const;
+    static uint32_t
+    txToPermissionType(TxType const& type);
 
     // tx type value is permission value minus one
-    TxType
-    permissionToTxType(uint32_t const& value) const;
+    static TxType
+    permissionToTxType(uint32_t const& value);
 };
 
 }  // namespace xrpl

include/xrpl/protocol/STAmount.h

@@ -42,8 +42,8 @@ private:
 public:
     using value_type = STAmount;
 
-    static int const cMinOffset = -96;
-    static int const cMaxOffset = 80;
+    static int constexpr cMinOffset = -96;
+    static int constexpr cMaxOffset = 80;
 
     // Maximum native value supported by the code
     constexpr static std::uint64_t cMinValue = 1'000'000'000'000'000ull;
@@ -739,6 +739,21 @@ canAdd(STAmount const& amt1, STAmount const& amt2);
 bool
 canSubtract(STAmount const& amt1, STAmount const& amt2);
 
+/** Get the scale of a Number for a given asset.
+ *
+ * "scale" is similar to "exponent", but from the perspective of STAmount, which has different rules
+ * and mantissa ranges for determining the exponent than Number.
+ *
+ * @param number The Number to get the scale of.
+ * @param asset The asset to use for determining the scale.
+ * @return The scale of this Number for the given asset.
+ */
+inline int
+scale(Number const& number, Asset const& asset)
+{
+    return STAmount{asset, number}.exponent();
+}
+
 }  // namespace xrpl
 
 //------------------------------------------------------------------------------

include/xrpl/protocol/Serializer.h

@@ -336,7 +336,7 @@ public:
         static_assert(N > 0, "");
     }
 
-    std::size_t
+    [[nodiscard]] bool
     empty() const noexcept
     {
         return remain_ == 0;

include/xrpl/protocol/detail/features.macro

@@ -16,6 +16,7 @@
 // Add new amendments to the top of this list.
 // Keep it sorted in reverse chronological order.
 
+XRPL_FIX   (Security3_1_3,               Supported::no, VoteBehavior::DefaultNo)
 XRPL_FIX   (PermissionedDomainInvariant, Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (ExpiredNFTokenOfferRemoval, Supported::yes, VoteBehavior::DefaultNo)
 XRPL_FIX    (BatchInnerSigs,             Supported::no, VoteBehavior::DefaultNo)

include/xrpl/shamap/SHAMap.h

@@ -520,7 +520,7 @@ private:
     // getMissingNodes helper functions
     void
     gmn_ProcessNodes(MissingNodes&, MissingNodes::StackEntry& node);
-    void
+    static void
     gmn_ProcessDeferredReads(MissingNodes&);
 
     // fetch from DB helper function

include/xrpl/tx/ApplyContext.h

@@ -111,7 +111,7 @@ public:
     checkInvariants(TER const result, XRPAmount const fee);
 
 private:
-    TER
+    static TER
     failInvariantCheck(TER const result);
 
     template <std::size_t... Is>

include/xrpl/tx/invariants/FreezeInvariant.h

@@ -48,7 +48,7 @@ private:
     bool
     isValidEntry(std::shared_ptr<SLE const> const& before, std::shared_ptr<SLE const> const& after);
 
-    STAmount
+    static STAmount
     calculateBalanceChange(
         std::shared_ptr<SLE const> const& before,
         std::shared_ptr<SLE const> const& after,
@@ -63,7 +63,7 @@ private:
     std::shared_ptr<SLE const>
     findIssuer(AccountID const& issuerID, ReadView const& view);
 
-    bool
+    static bool
     validateIssuerChanges(
         std::shared_ptr<SLE const> const& issuer,
         IssuerChanges const& changes,
@@ -71,7 +71,7 @@ private:
         beast::Journal const& j,
         bool enforce);
 
-    bool
+    static bool
     validateFrozenState(
         BalanceChange const& change,
         bool high,

include/xrpl/tx/invariants/InvariantCheck.h

@@ -111,7 +111,7 @@ public:
     void
     visitEntry(bool, std::shared_ptr<SLE const> const&, std::shared_ptr<SLE const> const&);
 
-    bool
+    static bool
     finalize(STTx const&, TER const, XRPAmount const, ReadView const&, beast::Journal const&);
 };
 

include/xrpl/tx/invariants/LoanInvariant.h

@@ -41,8 +41,8 @@ class ValidLoanBroker
     // for LoanBroker pseudo-accounts.
     std::vector<SLE::const_pointer> mpts_;
 
-    bool
-    goodZeroDirectory(ReadView const& view, SLE::const_ref dir, beast::Journal const& j) const;
+    static bool
+    goodZeroDirectory(ReadView const& view, SLE::const_ref dir, beast::Journal const& j);
 
 public:
     void

include/xrpl/tx/invariants/VaultInvariant.h

@@ -8,6 +8,7 @@
 #include <xrpl/protocol/STTx.h>
 #include <xrpl/protocol/TER.h>
 
+#include <optional>
 #include <unordered_map>
 #include <vector>
 
@@ -60,11 +61,19 @@ class ValidVault
         Shares static make(SLE const&);
     };
 
+public:
+    struct DeltaInfo final
+    {
+        Number delta = numZero;
+        std::optional<int> scale;
+    };
+
+private:
     std::vector<Vault> afterVault_ = {};
     std::vector<Shares> afterMPTs_ = {};
     std::vector<Vault> beforeVault_ = {};
     std::vector<Shares> beforeMPTs_ = {};
-    std::unordered_map<uint256, Number> deltas_ = {};
+    std::unordered_map<uint256, DeltaInfo> deltas_ = {};
 
 public:
     void
@@ -72,6 +81,10 @@ public:
 
     bool
     finalize(STTx const&, TER const, XRPAmount const, ReadView const&, beast::Journal const&);
+
+    // Compute the coarsest scale required to represent all numbers
+    [[nodiscard]] static std::int32_t
+    computeCoarsestScale(std::vector<DeltaInfo> const& numbers);
 };
 
 }  // namespace xrpl

include/xrpl/tx/paths/AMMOffer.h

@@ -2,6 +2,7 @@
 
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/Quality.h>
 #include <xrpl/protocol/TER.h>
 

include/xrpl/tx/paths/detail/StrandFlow.h

@@ -1,7 +1,9 @@
 #pragma once
 
 #include <xrpl/basics/Log.h>
-#include <xrpl/ledger/Credit.h>
+#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/IOUAmount.h>
 #include <xrpl/protocol/XRPAmount.h>

include/xrpl/tx/transactors/dex/AMMUtils.h

@@ -3,6 +3,7 @@
 #include <xrpl/basics/Expected.h>
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/STLedgerEntry.h>
 #include <xrpl/protocol/TER.h>

include/xrpl/tx/transactors/dex/AMMWithdraw.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/tx/Transactor.h>
 
 namespace xrpl {

include/xrpl/tx/transactors/lending/LendingHelpers.h

@@ -171,7 +171,7 @@ getAssetsTotalScale(SLE::const_ref vaultSle)
 {
     if (!vaultSle)
         return Number::minExponent - 1;  // LCOV_EXCL_LINE
-    return STAmount{vaultSle->at(sfAsset), vaultSle->at(sfAssetsTotal)}.exponent();
+    return scale(vaultSle->at(sfAssetsTotal), vaultSle->at(sfAsset));
 }
 
 TER

src/libxrpl/basics/Number.cpp

@@ -981,7 +981,7 @@ root(Number f, unsigned d)
     auto ex = [e = e, di = di]()  // Euclidean remainder of e/d
     {
         int k = (e >= 0 ? e : e - (di - 1)) / di;
-        int k2 = e - k * di;
+        int k2 = e - (k * di);
         if (k2 == 0)
             return 0;
         return di - k2;
@@ -998,7 +998,7 @@ root(Number f, unsigned d)
     }
 
     // Quadratic least squares curve fit of f^(1/d) in the range [0, 1]
-    auto const D = ((6 * di + 11) * di + 6) * di + 1;
+    auto const D = (((6 * di + 11) * di + 6) * di) + 1;
     auto const a0 = 3 * di * ((2 * di - 3) * di + 1);
     auto const a1 = 24 * di * (2 * di - 1);
     auto const a2 = -30 * (di - 1) * di;

src/libxrpl/basics/ResolverAsio.cpp

@@ -169,7 +169,7 @@ public:
         XRPL_ASSERT(m_stopped == true, "xrpl::ResolverAsioImpl::start : stopped");
         XRPL_ASSERT(m_stop_called == false, "xrpl::ResolverAsioImpl::start : not stopping");
 
-        if (m_stopped.exchange(false) == true)
+        if (m_stopped.exchange(false))
         {
             {
                 std::lock_guard lk{m_mut};
@@ -182,7 +182,7 @@ public:
     void
     stop_async() override
     {
-        if (m_stop_called.exchange(true) == false)
+        if (!m_stop_called.exchange(true))
         {
             boost::asio::dispatch(
                 m_io_context,
@@ -229,7 +229,7 @@ public:
     {
         XRPL_ASSERT(m_stop_called == true, "xrpl::ResolverAsioImpl::do_stop : stopping");
 
-        if (m_stopped.exchange(true) == false)
+        if (!m_stopped.exchange(true))
         {
             m_work.clear();
             m_resolver.cancel();
@@ -271,7 +271,7 @@ public:
                 m_strand, std::bind(&ResolverAsioImpl::do_work, this, CompletionCounter(this))));
     }
 
-    HostAndPort
+    static HostAndPort
     parseName(std::string const& str)
     {
         // first attempt to parse as an endpoint (IP addr + port).
@@ -319,7 +319,7 @@ public:
     void
     do_work(CompletionCounter)
     {
-        if (m_stop_called == true)
+        if (m_stop_called)
             return;
 
         // We don't have any work to do at this time
@@ -367,7 +367,7 @@ public:
     {
         XRPL_ASSERT(!names.empty(), "xrpl::ResolverAsioImpl::do_resolve : names non-empty");
 
-        if (m_stop_called == false)
+        if (!m_stop_called)
         {
             m_work.emplace_back(names, handler);
 

src/libxrpl/basics/StringUtilities.cpp

@@ -24,7 +24,7 @@ sqlBlobLiteral(Blob const& blob)
 {
     std::string j;
 
-    j.reserve(blob.size() * 2 + 3);
+    j.reserve((blob.size() * 2) + 3);
     j.push_back('X');
     j.push_back('\'');
     boost::algorithm::hex(blob.begin(), blob.end(), std::back_inserter(j));

src/libxrpl/basics/base64.cpp

@@ -107,7 +107,7 @@ encode(void* dest, void const* src, std::size_t len)
     char const* in = static_cast<char const*>(src);
     auto const tab = base64::get_alphabet();
 
-    for (auto n = len / 3; n--;)
+    for (auto n = len / 3; n != 0u; --n)
     {
         *out++ = tab[(in[0] & 0xfc) >> 2];
         *out++ = tab[((in[0] & 0x03) << 4) + ((in[1] & 0xf0) >> 4)];
@@ -162,7 +162,7 @@ decode(void* dest, char const* src, std::size_t len)
 
     auto const inverse = base64::get_inverse();
 
-    while (len-- && *in != '=')
+    while (((len--) != 0u) && *in != '=')
     {
         auto const v = inverse[*in];
         if (v == -1)
@@ -181,7 +181,7 @@ decode(void* dest, char const* src, std::size_t len)
         }
     }
 
-    if (i)
+    if (i != 0)
     {
         c3[0] = (c4[0] << 2) + ((c4[1] & 0x30) >> 4);
         c3[1] = ((c4[1] & 0xf) << 4) + ((c4[2] & 0x3c) >> 2);

src/libxrpl/basics/make_SSLContext.cpp

@@ -253,7 +253,7 @@ initAuthenticated(
         // VFALCO Replace fopen() with RAII
         FILE* f = fopen(chain_file.c_str(), "r");
 
-        if (!f)
+        if (f == nullptr)
         {
             LogicError(
                 "Problem opening SSL chain file" +

src/libxrpl/beast/insight/StatsDCollector.cpp

@@ -352,7 +352,7 @@ public:
         }
     }
 
-    void
+    static void
     log(std::vector<boost::asio::const_buffer> const& buffers)
     {
         (void)buffers;

src/libxrpl/beast/net/IPAddressV6.cpp

@@ -10,7 +10,7 @@ bool
 is_private(AddressV6 const& addr)
 {
     return (
-        (addr.to_bytes()[0] & 0xfd) ||  // TODO  fc00::/8 too ?
+        ((addr.to_bytes()[0] & 0xfd) != 0) ||  // TODO  fc00::/8 too ?
         (addr.is_v4_mapped() &&
          is_private(boost::asio::ip::make_address_v4(boost::asio::ip::v4_mapped, addr))));
 }

src/libxrpl/beast/net/IPEndpoint.cpp

@@ -57,7 +57,7 @@ Endpoint::to_string() const
     if (port() != 0 && address().is_v6())
         s += '[';
     s += address().to_string();
-    if (port())
+    if (port() != 0u)
     {
         if (address().is_v6())
             s += ']';
@@ -111,7 +111,7 @@ operator>>(std::istream& is, Endpoint& endpoint)
         // so we continue to honor that here by assuming we are at the end
         // of the address portion if we hit a space (or the separator
         // we were expecting to see)
-        if (isspace(static_cast<unsigned char>(i)) || (readTo && i == readTo))
+        if ((isspace(static_cast<unsigned char>(i)) != 0) || ((readTo != 0) && i == readTo))
             break;
 
         if ((i == '.') || (i >= '0' && i <= ':') || (i >= 'a' && i <= 'f') ||
@@ -121,13 +121,13 @@ operator>>(std::istream& is, Endpoint& endpoint)
 
             // don't exceed a reasonable length...
             if (addrStr.size() == INET6_ADDRSTRLEN ||
-                (readTo && readTo == ':' && addrStr.size() > 15))
+                ((readTo != 0) && readTo == ':' && addrStr.size() > 15))
             {
                 is.setstate(std::ios_base::failbit);
                 return is;
             }
 
-            if (!readTo && (i == '.' || i == ':'))
+            if ((readTo == 0) && (i == '.' || i == ':'))
             {
                 // if we see a dot first, must be IPv4
                 // otherwise must be non-bracketed IPv6
@@ -145,7 +145,7 @@ operator>>(std::istream& is, Endpoint& endpoint)
     if (readTo == ']' && is.rdbuf()->in_avail() > 0)
     {
         is.get(i);
-        if (!(isspace(static_cast<unsigned char>(i)) || i == ':'))
+        if ((isspace(static_cast<unsigned char>(i)) == 0) && i != ':')
         {
             is.unget();
             is.setstate(std::ios_base::failbit);

src/libxrpl/core/detail/JobQueue.cpp

@@ -84,8 +84,7 @@ JobQueue::addRefCountedJob(JobType type, std::string const& name, JobFunction co
 
         JobType const type(job.getType());
         XRPL_ASSERT(type != jtINVALID, "xrpl::JobQueue::addRefCountedJob : has valid job type");
-        XRPL_ASSERT(
-            m_jobSet.find(job) != m_jobSet.end(), "xrpl::JobQueue::addRefCountedJob : job found");
+        XRPL_ASSERT(m_jobSet.contains(job), "xrpl::JobQueue::addRefCountedJob : job found");
         perfLog_.jobQueue(type);
 
         JobTypeData& data(getJobTypeData(type));

src/libxrpl/core/detail/LoadMonitor.cpp

@@ -141,7 +141,7 @@ LoadMonitor::isOver()
     update();
 
     if (mLatencyEvents == 0)
-        return 0;
+        return false;
 
     return isOverTarget(
         mLatencyMSAvg / (mLatencyEvents * 4), mLatencyMSPeak / (mLatencyEvents * 4));

src/libxrpl/core/detail/Workers.cpp

@@ -47,7 +47,7 @@ Workers::setNumberOfThreads(int numberOfThreads)
     if (m_numberOfThreads == numberOfThreads)
         return;
 
-    if (perfLog_)
+    if (perfLog_ != nullptr)
         perfLog_->resizeJobs(numberOfThreads);
 
     if (numberOfThreads > m_numberOfThreads)

src/libxrpl/crypto/RFC1751.cpp

@@ -210,8 +210,8 @@ RFC1751::extract(char const* s, int start, int length)
 
     int const shiftR = 24 - (length + (start % 8));
     cl = s[start / 8];  // get components
-    cc = (shiftR < 16) ? s[start / 8 + 1] : 0;
-    cr = (shiftR < 8) ? s[start / 8 + 2] : 0;
+    cc = (shiftR < 16) ? s[(start / 8) + 1] : 0;
+    cr = (shiftR < 8) ? s[(start / 8) + 2] : 0;
 
     x = ((long)(cl << 8 | cc) << 8 | cr);  // Put bits together
     x = x >> shiftR;                       // Right justify number
@@ -265,13 +265,13 @@ RFC1751::insert(char* s, int x, int start, int length)
     if (shift + length > 16)
     {
         s[start / 8] |= cl;
-        s[start / 8 + 1] |= cc;
-        s[start / 8 + 2] |= cr;
+        s[(start / 8) + 1] |= cc;
+        s[(start / 8) + 2] |= cr;
     }
     else if (shift + length > 8)
     {
         s[start / 8] |= cc;
-        s[start / 8 + 1] |= cr;
+        s[(start / 8) + 1] |= cr;
     }
     else
     {
@@ -284,7 +284,7 @@ RFC1751::standard(std::string& strWord)
 {
     for (auto& letter : strWord)
     {
-        if (islower(static_cast<unsigned char>(letter)))
+        if (islower(static_cast<unsigned char>(letter)) != 0)
         {
             letter = toupper(static_cast<unsigned char>(letter));
         }
@@ -312,10 +312,10 @@ RFC1751::wsrch(std::string const& strWord, int iMin, int iMax)
     while (iResult < 0 && iMin != iMax)
     {
         // Have a range to search.
-        int iMid = iMin + (iMax - iMin) / 2;
+        int iMid = iMin + ((iMax - iMin) / 2);
         int iDir = strWord.compare(s_dictionary[iMid]);
 
-        if (!iDir)
+        if (iDir == 0)
         {
             iResult = iMid;  // Found it.
         }

src/libxrpl/json/Writer.cpp

@@ -152,7 +152,7 @@ public:
 #ifndef NDEBUG
         // Make sure we haven't already seen this tag.
         auto& tags = stack_.top().tags;
-        check(tags.find(tag) == tags.end(), "Already seen tag " + tag);
+        check(!tags.contains(tag), "Already seen tag " + tag);
         tags.insert(tag);
 #endif
 

src/libxrpl/json/json_reader.cpp

@@ -296,7 +296,7 @@ Reader::match(Location pattern, int patternLength)
 
     int index = patternLength;
 
-    while (index--)
+    while ((index--) != 0)
     {
         if (current_[index] != pattern[index])
             return false;
@@ -362,7 +362,7 @@ Reader::readNumber()
 
         while (current_ != end_)
         {
-            if (!std::isdigit(static_cast<unsigned char>(*current_)))
+            if (std::isdigit(static_cast<unsigned char>(*current_)) == 0)
             {
                 auto ret =
                     std::find(std::begin(extended_tokens), std::end(extended_tokens), *current_);
@@ -913,7 +913,7 @@ Reader::getFormattedErrorMessages() const
         formattedMessage += "* " + getLocationLineAndColumn(error.token_.start_) + "\n";
         formattedMessage += "  " + error.message_ + "\n";
 
-        if (error.extra_)
+        if (error.extra_ != nullptr)
             formattedMessage += "See " + getLocationLineAndColumn(error.extra_) + " for detail.\n";
     }
 

src/libxrpl/json/json_value.cpp

@@ -40,10 +40,10 @@ public:
         //   return 0;
 
         if (length == unknown)
-            length = value ? (unsigned int)strlen(value) : 0;
+            length = (value != nullptr) ? (unsigned int)strlen(value) : 0;
 
         char* newString = static_cast<char*>(malloc(length + 1));
-        if (value)
+        if (value != nullptr)
             memcpy(newString, value, length);
         newString[length] = 0;
         return newString;
@@ -52,7 +52,7 @@ public:
     void
     releaseStringValue(char* value) override
     {
-        if (value)
+        if (value != nullptr)
             free(value);
     }
 };
@@ -108,14 +108,14 @@ Value::CZString::CZString(CZString const& other)
 
 Value::CZString::~CZString()
 {
-    if (cstr_ && index_ == duplicate)
+    if ((cstr_ != nullptr) && index_ == duplicate)
         valueAllocator()->releaseMemberName(const_cast<char*>(cstr_));
 }
 
 bool
 Value::CZString::operator<(CZString const& other) const
 {
-    if (cstr_ && other.cstr_)
+    if ((cstr_ != nullptr) && (other.cstr_ != nullptr))
         return strcmp(cstr_, other.cstr_) < 0;
 
     return index_ < other.index_;
@@ -124,7 +124,7 @@ Value::CZString::operator<(CZString const& other) const
 bool
 Value::CZString::operator==(CZString const& other) const
 {
-    if (cstr_ && other.cstr_)
+    if ((cstr_ != nullptr) && (other.cstr_ != nullptr))
         return strcmp(cstr_, other.cstr_) == 0;
 
     return index_ == other.index_;
@@ -251,7 +251,7 @@ Value::Value(Value const& other) : type_(other.type_)
             break;
 
         case stringValue:
-            if (other.value_.string_)
+            if (other.value_.string_ != nullptr)
             {
                 value_.string_ = valueAllocator()->duplicateStringValue(other.value_.string_);
                 allocated_ = true;
@@ -294,7 +294,7 @@ Value::~Value()
 
         case arrayValue:
         case objectValue:
-            if (value_.map_)
+            if (value_.map_ != nullptr)
                 delete value_.map_;
             break;
 
@@ -392,11 +392,11 @@ operator<(Value const& x, Value const& y)
             return x.value_.real_ < y.value_.real_;
 
         case booleanValue:
-            return x.value_.bool_ < y.value_.bool_;
+            return static_cast<int>(x.value_.bool_) < static_cast<int>(y.value_.bool_);
 
         case stringValue:
-            return (x.value_.string_ == 0 && y.value_.string_) ||
-                (y.value_.string_ && x.value_.string_ &&
+            return (x.value_.string_ == 0 && (y.value_.string_ != nullptr)) ||
+                ((y.value_.string_ != nullptr) && (x.value_.string_ != nullptr) &&
                  strcmp(x.value_.string_, y.value_.string_) < 0);
 
         case arrayValue:
@@ -413,7 +413,7 @@ operator<(Value const& x, Value const& y)
             // LCOV_EXCL_STOP
     }
 
-    return 0;  // unreachable
+    return false;  // unreachable
 }
 
 bool
@@ -422,9 +422,9 @@ operator==(Value const& x, Value const& y)
     if (x.type_ != y.type_)
     {
         if (x.type_ == intValue && y.type_ == uintValue)
-            return !integerCmp(x.value_.int_, y.value_.uint_);
+            return integerCmp(x.value_.int_, y.value_.uint_) == 0;
         if (x.type_ == uintValue && y.type_ == intValue)
-            return !integerCmp(y.value_.int_, x.value_.uint_);
+            return integerCmp(y.value_.int_, x.value_.uint_) == 0;
         return false;
     }
 
@@ -447,8 +447,8 @@ operator==(Value const& x, Value const& y)
 
         case stringValue:
             return x.value_.string_ == y.value_.string_ ||
-                (y.value_.string_ && x.value_.string_ &&
-                 !strcmp(x.value_.string_, y.value_.string_));
+                ((y.value_.string_ != nullptr) && (x.value_.string_ != nullptr) &&
+                 (strcmp(x.value_.string_, y.value_.string_) == 0));
 
         case arrayValue:
         case objectValue:
@@ -461,7 +461,7 @@ operator==(Value const& x, Value const& y)
             // LCOV_EXCL_STOP
     }
 
-    return 0;  // unreachable
+    return false;  // unreachable
 }
 
 char const*
@@ -480,7 +480,7 @@ Value::asString() const
             return "";
 
         case stringValue:
-            return value_.string_ ? value_.string_ : "";
+            return (value_.string_ != nullptr) ? value_.string_ : "";
 
         case booleanValue:
             return value_.bool_ ? "true" : "false";
@@ -525,7 +525,7 @@ Value::asInt() const
 
         case realValue:
             JSON_ASSERT_MESSAGE(
-                value_.real_ >= minInt && value_.real_ <= maxInt,
+                (value_.real_ >= minInt && value_.real_ <= maxInt),
                 "Real out of signed integer range");
             return Int(value_.real_);
 
@@ -533,7 +533,7 @@ Value::asInt() const
             return value_.bool_ ? 1 : 0;
 
         case stringValue: {
-            char const* const str{value_.string_ ? value_.string_ : ""};
+            char const* const str{(value_.string_ != nullptr) ? value_.string_ : ""};
             return beast::lexicalCastThrow<int>(str);
         }
 
@@ -584,7 +584,7 @@ Value::asAbsUInt() const
             return value_.bool_ ? 1 : 0;
 
         case stringValue: {
-            char const* const str{value_.string_ ? value_.string_ : ""};
+            char const* const str{(value_.string_ != nullptr) ? value_.string_ : ""};
             auto const temp = beast::lexicalCastThrow<std::int64_t>(str);
             if (temp < 0)
             {
@@ -626,14 +626,15 @@ Value::asUInt() const
 
         case realValue:
             JSON_ASSERT_MESSAGE(
-                value_.real_ >= 0 && value_.real_ <= maxUInt, "Real out of unsigned integer range");
+                (value_.real_ >= 0 && value_.real_ <= maxUInt),
+                "Real out of unsigned integer range");
             return UInt(value_.real_);
 
         case booleanValue:
             return value_.bool_ ? 1 : 0;
 
         case stringValue: {
-            char const* const str{value_.string_ ? value_.string_ : ""};
+            char const* const str{(value_.string_ != nullptr) ? value_.string_ : ""};
             return beast::lexicalCastThrow<unsigned int>(str);
         }
 
@@ -703,7 +704,7 @@ Value::asBool() const
             return value_.bool_;
 
         case stringValue:
-            return value_.string_ && value_.string_[0] != 0;
+            return (value_.string_ != nullptr) && value_.string_[0] != 0;
 
         case arrayValue:
         case objectValue:
@@ -745,13 +746,13 @@ Value::isConvertibleTo(ValueType other) const
                 other == realValue || other == stringValue || other == booleanValue;
 
         case booleanValue:
-            return (other == nullValue && value_.bool_ == false) || other == intValue ||
+            return (other == nullValue && !value_.bool_) || other == intValue ||
                 other == uintValue || other == realValue || other == stringValue ||
                 other == booleanValue;
 
         case stringValue:
             return other == stringValue ||
-                (other == nullValue && (!value_.string_ || value_.string_[0] == 0));
+                (other == nullValue && ((value_.string_ == nullptr) || value_.string_[0] == 0));
 
         case arrayValue:
             return other == arrayValue || (other == nullValue && value_.map_->empty());
@@ -813,10 +814,10 @@ operator bool() const
     if (isString())
     {
         auto s = asCString();
-        return s && s[0];
+        return (s != nullptr) && (s[0] != 0);
     }
 
-    return !(isArray() || isObject()) || size();
+    return !(isArray() || isObject()) || (size() != 0u);
 }
 
 void
@@ -1139,7 +1140,7 @@ Value::begin() const
     {
         case arrayValue:
         case objectValue:
-            if (value_.map_)
+            if (value_.map_ != nullptr)
                 return const_iterator(value_.map_->begin());
 
             break;
@@ -1157,7 +1158,7 @@ Value::end() const
     {
         case arrayValue:
         case objectValue:
-            if (value_.map_)
+            if (value_.map_ != nullptr)
                 return const_iterator(value_.map_->end());
 
             break;
@@ -1175,7 +1176,7 @@ Value::begin()
     {
         case arrayValue:
         case objectValue:
-            if (value_.map_)
+            if (value_.map_ != nullptr)
                 return iterator(value_.map_->begin());
             break;
         default:
@@ -1192,7 +1193,7 @@ Value::end()
     {
         case arrayValue:
         case objectValue:
-            if (value_.map_)
+            if (value_.map_ != nullptr)
                 return iterator(value_.map_->end());
             break;
         default:

src/libxrpl/json/json_valueiterator.cpp

@@ -89,7 +89,7 @@ ValueIteratorBase::key() const
 {
     Value::CZString const czString = (*current_).first;
 
-    if (czString.c_str())
+    if (czString.c_str() != nullptr)
     {
         if (czString.isStaticString())
             return Value(StaticString(czString.c_str()));
@@ -105,7 +105,7 @@ ValueIteratorBase::index() const
 {
     Value::CZString const czString = (*current_).first;
 
-    if (!czString.c_str())
+    if (czString.c_str() == nullptr)
         return czString.index();
 
     return Value::UInt(-1);
@@ -115,7 +115,7 @@ char const*
 ValueIteratorBase::memberName() const
 {
     char const* name = (*current_).first.c_str();
-    return name ? name : "";
+    return (name != nullptr) ? name : "";
 }
 
 // //////////////////////////////////////////////////////////////////

src/libxrpl/json/json_writer.cpp

@@ -23,7 +23,7 @@ isControlCharacter(char ch)
 static bool
 containsControlCharacter(char const* str)
 {
-    while (*str)
+    while (*str != 0)
     {
         if (isControlCharacter(*(str++)))
             return true;
@@ -106,7 +106,7 @@ valueToQuotedString(char const* value)
     // We have to walk value and escape any special characters.
     // Appending to std::string is not efficient, but this should be rare.
     // (Note: forward slashes are *not* rare, but I am not escaping them.)
-    unsigned maxsize = strlen(value) * 2 + 3;  // all-escaped+quotes+NULL
+    unsigned maxsize = (strlen(value) * 2) + 3;  // all-escaped+quotes+NULL
     std::string result;
     result.reserve(maxsize);  // to avoid lots of mallocs
     result += "\"";
@@ -416,7 +416,7 @@ StyledWriter::isMultilineArray(Value const& value)
     {
         childValues_.reserve(size);
         addChildValues_ = true;
-        int lineLength = 4 + (size - 1) * 2;  // '[ ' + ', '*n + ' ]'
+        int lineLength = 4 + ((size - 1) * 2);  // '[ ' + ', '*n + ' ]'
 
         for (int index = 0; index < size; ++index)
         {
@@ -651,7 +651,7 @@ StyledStreamWriter::isMultilineArray(Value const& value)
     {
         childValues_.reserve(size);
         addChildValues_ = true;
-        int lineLength = 4 + (size - 1) * 2;  // '[ ' + ', '*n + ' ]'
+        int lineLength = 4 + ((size - 1) * 2);  // '[ ' + ', '*n + ' ]'
 
         for (int index = 0; index < size; ++index)
         {

src/libxrpl/ledger/AcceptedLedgerTx.cpp

@@ -2,6 +2,7 @@
 #include <xrpl/basics/StringUtilities.h>
 #include <xrpl/ledger/AcceptedLedgerTx.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
 #include <xrpl/protocol/UintTypes.h>
 #include <xrpl/protocol/jss.h>
 

src/libxrpl/ledger/ApplyStateTable.cpp

@@ -275,9 +275,7 @@ ApplyStateTable::exists(ReadView const& base, Keylet const& k) const
         case Action::modify:
             break;
     }
-    if (!k.check(*sle))
-        return false;
-    return true;
+    return k.check(*sle);
 }
 
 auto

src/libxrpl/ledger/ApplyView.cpp

@@ -36,7 +36,7 @@ findPreviousPage(ApplyView& view, Keylet const& directory, SLE::ref start)
 
     auto node = start;
 
-    if (page)
+    if (page != 0u)
     {
         node = view.peek(keylet::page(directory, page));
         if (!node)

src/libxrpl/ledger/BookDirs.cpp

@@ -1,5 +1,6 @@
 #include <xrpl/ledger/BookDirs.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/Indexes.h>
 
 namespace xrpl {

src/libxrpl/ledger/CanonicalTXSet.cpp

@@ -1,4 +1,4 @@
-#include <xrpld/app/misc/CanonicalTXSet.h>
+#include <xrpl/ledger/CanonicalTXSet.h>
 
 namespace xrpl {
 

src/libxrpl/ledger/Credit.cpp

@@ -1,60 +0,0 @@
-#include <xrpl/ledger/ReadView.h>
-#include <xrpl/protocol/AmountConversions.h>
-#include <xrpl/protocol/Indexes.h>
-#include <xrpl/protocol/STAmount.h>
-
-namespace xrpl {
-
-STAmount
-creditLimit(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency)
-{
-    STAmount result(Issue{currency, account});
-
-    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
-
-    if (sleRippleState)
-    {
-        result = sleRippleState->getFieldAmount(account < issuer ? sfLowLimit : sfHighLimit);
-        result.setIssuer(account);
-    }
-
-    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditLimit : result issuer match");
-    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditLimit : result currency match");
-    return result;
-}
-
-IOUAmount
-creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur)
-{
-    return toAmount<IOUAmount>(creditLimit(v, acc, iss, cur));
-}
-
-STAmount
-creditBalance(
-    ReadView const& view,
-    AccountID const& account,
-    AccountID const& issuer,
-    Currency const& currency)
-{
-    STAmount result(Issue{currency, account});
-
-    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
-
-    if (sleRippleState)
-    {
-        result = sleRippleState->getFieldAmount(sfBalance);
-        if (account < issuer)
-            result.negate();
-        result.setIssuer(account);
-    }
-
-    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditBalance : result issuer match");
-    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditBalance : result currency match");
-    return result;
-}
-
-}  // namespace xrpl

src/libxrpl/ledger/Ledger.cpp

@@ -1,19 +1,9 @@
-#include <xrpld/app/ledger/InboundLedgers.h>
-#include <xrpld/app/ledger/Ledger.h>
-#include <xrpld/app/ledger/LedgerToJson.h>
-#include <xrpld/app/ledger/PendingSaves.h>
-#include <xrpld/app/main/Application.h>
-#include <xrpld/consensus/LedgerTiming.h>
-#include <xrpld/core/Config.h>
-
 #include <xrpl/basics/Log.h>
 #include <xrpl/basics/contract.h>
 #include <xrpl/beast/utility/instrumentation.h>
-#include <xrpl/core/HashRouter.h>
-#include <xrpl/core/JobQueue.h>
 #include <xrpl/json/to_string.h>
-#include <xrpl/nodestore/Database.h>
-#include <xrpl/nodestore/detail/DatabaseNodeImp.h>
+#include <xrpl/ledger/Ledger.h>
+#include <xrpl/ledger/LedgerTiming.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/HashPrefix.h>
 #include <xrpl/protocol/Indexes.h>
@@ -21,7 +11,6 @@
 #include <xrpl/protocol/SecretKey.h>
 #include <xrpl/protocol/digest.h>
 #include <xrpl/protocol/jss.h>
-#include <xrpl/rdb/RelationalDatabase.h>
 
 #include <utility>
 #include <vector>
@@ -30,23 +19,6 @@ namespace xrpl {
 
 create_genesis_t const create_genesis{};
 
-uint256
-calculateLedgerHash(LedgerHeader const& info)
-{
-    // VFALCO This has to match addRaw in View.h.
-    return sha512Half(
-        HashPrefix::ledgerMaster,
-        std::uint32_t(info.seq),
-        std::uint64_t(info.drops.drops()),
-        info.parentHash,
-        info.txHash,
-        info.accountHash,
-        std::uint32_t(info.parentCloseTime.time_since_epoch().count()),
-        std::uint32_t(info.closeTime.time_since_epoch().count()),
-        std::uint8_t(info.closeTimeResolution.count()),
-        std::uint8_t(info.closeFlags));
-}
-
 //------------------------------------------------------------------------------
 
 class Ledger::sles_iter_impl : public sles_type::iter_base
@@ -138,8 +110,8 @@ public:
     {
         auto const& item = *iter_;
         if (metadata_)
-            return deserializeTxPlusMeta(item);
-        return {deserializeTx(item), nullptr};
+            return Ledger::deserializeTxPlusMeta(item);
+        return {Ledger::deserializeTx(item), nullptr};
     }
 };
 
@@ -147,13 +119,15 @@ public:
 
 Ledger::Ledger(
     create_genesis_t,
-    Config const& config,
+    Rules const& rules,
+    Fees const& fees,
     std::vector<uint256> const& amendments,
     Family& family)
     : mImmutable(false)
     , txMap_(SHAMapType::TRANSACTION, family)
     , stateMap_(SHAMapType::STATE, family)
-    , rules_{config.features}
+    , fees_(fees)
+    , rules_(rules)
     , j_(beast::Journal(beast::Journal::getNullSink()))
 {
     header_.seq = 1;
@@ -182,19 +156,19 @@ Ledger::Ledger(
         // Whether featureXRPFees is supported will depend on startup options.
         if (std::find(amendments.begin(), amendments.end(), featureXRPFees) != amendments.end())
         {
-            sle->at(sfBaseFeeDrops) = config.FEES.reference_fee;
-            sle->at(sfReserveBaseDrops) = config.FEES.account_reserve;
-            sle->at(sfReserveIncrementDrops) = config.FEES.owner_reserve;
+            sle->at(sfBaseFeeDrops) = fees.base;
+            sle->at(sfReserveBaseDrops) = fees.reserve;
+            sle->at(sfReserveIncrementDrops) = fees.increment;
         }
         else
         {
-            if (auto const f = config.FEES.reference_fee.dropsAs<std::uint64_t>())
+            if (auto const f = fees.base.dropsAs<std::uint64_t>())
                 sle->at(sfBaseFee) = *f;
-            if (auto const f = config.FEES.account_reserve.dropsAs<std::uint32_t>())
+            if (auto const f = fees.reserve.dropsAs<std::uint32_t>())
                 sle->at(sfReserveBase) = *f;
-            if (auto const f = config.FEES.owner_reserve.dropsAs<std::uint32_t>())
+            if (auto const f = fees.increment.dropsAs<std::uint32_t>())
                 sle->at(sfReserveIncrement) = *f;
-            sle->at(sfReferenceFeeUnits) = Config::FEE_UNITS_DEPRECATED;
+            sle->at(sfReferenceFeeUnits) = FEE_UNITS_DEPRECATED;
         }
         rawInsert(sle);
     }
@@ -207,13 +181,15 @@ Ledger::Ledger(
     LedgerHeader const& info,
     bool& loaded,
     bool acquire,
-    Config const& config,
+    Rules const& rules,
+    Fees const& fees,
     Family& family,
     beast::Journal j)
     : mImmutable(true)
     , txMap_(SHAMapType::TRANSACTION, info.txHash, family)
     , stateMap_(SHAMapType::STATE, info.accountHash, family)
-    , rules_(config.features)
+    , fees_(fees)
+    , rules_(rules)
     , header_(info)
     , j_(j)
 {
@@ -235,7 +211,6 @@ Ledger::Ledger(
     txMap_.setImmutable();
     stateMap_.setImmutable();
 
-    defaultFees(config);
     if (!setup())
         loaded = false;
 
@@ -275,11 +250,11 @@ Ledger::Ledger(Ledger const& prevLedger, NetClock::time_point closeTime)
     }
 }
 
-Ledger::Ledger(LedgerHeader const& info, Config const& config, Family& family)
+Ledger::Ledger(LedgerHeader const& info, Rules const& rules, Family& family)
     : mImmutable(true)
     , txMap_(SHAMapType::TRANSACTION, info.txHash, family)
     , stateMap_(SHAMapType::STATE, info.accountHash, family)
-    , rules_{config.features}
+    , rules_(rules)
     , header_(info)
     , j_(beast::Journal(beast::Journal::getNullSink()))
 {
@@ -289,18 +264,19 @@ Ledger::Ledger(LedgerHeader const& info, Config const& config, Family& family)
 Ledger::Ledger(
     std::uint32_t ledgerSeq,
     NetClock::time_point closeTime,
-    Config const& config,
+    Rules const& rules,
+    Fees const& fees,
     Family& family)
     : mImmutable(false)
     , txMap_(SHAMapType::TRANSACTION, family)
     , stateMap_(SHAMapType::STATE, family)
-    , rules_{config.features}
+    , fees_(fees)
+    , rules_(rules)
     , j_(beast::Journal(beast::Journal::getNullSink()))
 {
     header_.seq = ledgerSeq;
     header_.closeTime = closeTime;
     header_.closeTimeResolution = ledgerDefaultTimeResolution;
-    defaultFees(config);
     setup();
 }
 
@@ -350,14 +326,14 @@ Ledger::addSLE(SLE const& sle)
 //------------------------------------------------------------------------------
 
 std::shared_ptr<STTx const>
-deserializeTx(SHAMapItem const& item)
+Ledger::deserializeTx(SHAMapItem const& item)
 {
     SerialIter sit(item.slice());
     return std::make_shared<STTx const>(sit);
 }
 
 std::pair<std::shared_ptr<STTx const>, std::shared_ptr<STObject const>>
-deserializeTxPlusMeta(SHAMapItem const& item)
+Ledger::deserializeTxPlusMeta(SHAMapItem const& item)
 {
     std::pair<std::shared_ptr<STTx const>, std::shared_ptr<STObject const>> result;
     SerialIter sit(item.slice());
@@ -636,20 +612,6 @@ Ledger::setup()
     return ret;
 }
 
-void
-Ledger::defaultFees(Config const& config)
-{
-    XRPL_ASSERT(
-        fees_.base == 0 && fees_.reserve == 0 && fees_.increment == 0,
-        "xrpl::Ledger::defaultFees : zero fees");
-    if (fees_.base == 0)
-        fees_.base = config.FEES.reference_fee;
-    if (fees_.reserve == 0)
-        fees_.reserve = config.FEES.account_reserve;
-    if (fees_.increment == 0)
-        fees_.increment = config.FEES.owner_reserve;
-}
-
 std::shared_ptr<SLE>
 Ledger::peek(Keylet const& k) const
 {
@@ -816,27 +778,17 @@ Ledger::walkLedger(beast::Journal j, bool parallel) const
 }
 
 bool
-Ledger::assertSensible(beast::Journal ledgerJ) const
+Ledger::isSensible() const
 {
-    if (header_.hash.isNonZero() && header_.accountHash.isNonZero() &&
-        (header_.accountHash == stateMap_.getHash().as_uint256()) &&
-        (header_.txHash == txMap_.getHash().as_uint256()))
-    {
-        return true;
-    }
-
-    // LCOV_EXCL_START
-    Json::Value j = getJson({*this, {}});
-
-    j[jss::accountTreeHash] = to_string(header_.accountHash);
-    j[jss::transTreeHash] = to_string(header_.txHash);
-
-    JLOG(ledgerJ.fatal()) << "ledger is not sensible" << j;
-
-    UNREACHABLE("xrpl::Ledger::assertSensible : ledger is not sensible");
-
-    return false;
-    // LCOV_EXCL_STOP
+    if (header_.hash.isZero())
+        return false;
+    if (header_.accountHash.isZero())
+        return false;
+    if (header_.accountHash != stateMap_.getHash().as_uint256())
+        return false;
+    if (header_.txHash != txMap_.getHash().as_uint256())
+        return false;
+    return true;
 }
 
 // update the skip list with the information from our previous ledger
@@ -925,76 +877,6 @@ Ledger::isVotingLedger() const
     return ::xrpl::isVotingLedger(header_.seq + 1);
 }
 
-static bool
-saveValidatedLedger(Application& app, std::shared_ptr<Ledger const> const& ledger, bool current)
-{
-    auto j = app.journal("Ledger");
-    auto seq = ledger->header().seq;
-    if (!app.pendingSaves().startWork(seq))
-    {
-        // The save was completed synchronously
-        JLOG(j.debug()) << "Save aborted";
-        return true;
-    }
-
-    auto& db = app.getRelationalDatabase();
-
-    auto const res = db.saveValidatedLedger(ledger, current);
-
-    // Clients can now trust the database for
-    // information about this ledger sequence.
-    app.pendingSaves().finishWork(seq);
-    return res;
-}
-
-/** Save, or arrange to save, a fully-validated ledger
-    Returns false on error
-*/
-bool
-pendSaveValidated(
-    Application& app,
-    std::shared_ptr<Ledger const> const& ledger,
-    bool isSynchronous,
-    bool isCurrent)
-{
-    if (!app.getHashRouter().setFlags(ledger->header().hash, HashRouterFlags::SAVED))
-    {
-        // We have tried to save this ledger recently
-        auto stream = app.journal("Ledger").debug();
-        JLOG(stream) << "Double pend save for " << ledger->header().seq;
-
-        if (!isSynchronous || !app.pendingSaves().pending(ledger->header().seq))
-        {
-            // Either we don't need it to be finished
-            // or it is finished
-            return true;
-        }
-    }
-
-    XRPL_ASSERT(ledger->isImmutable(), "xrpl::pendSaveValidated : immutable ledger");
-
-    if (!app.pendingSaves().shouldWork(ledger->header().seq, isSynchronous))
-    {
-        auto stream = app.journal("Ledger").debug();
-        JLOG(stream) << "Pend save with seq in pending saves " << ledger->header().seq;
-
-        return true;
-    }
-
-    // See if we can use the JobQueue.
-    if (!isSynchronous &&
-        app.getJobQueue().addJob(
-            isCurrent ? jtPUBLEDGER : jtPUBOLDLEDGER,
-            std::to_string(ledger->seq()),
-            [&app, ledger, isCurrent]() { saveValidatedLedger(app, ledger, isCurrent); }))
-    {
-        return true;
-    }
-
-    // The JobQueue won't do the Job.  Do the save synchronously.
-    return saveValidatedLedger(app, ledger, isCurrent);
-}
-
 void
 Ledger::unshare() const
 {
@@ -1008,84 +890,5 @@ Ledger::invariants() const
     stateMap_.invariants();
     txMap_.invariants();
 }
-//------------------------------------------------------------------------------
-
-/*
- * Make ledger using info loaded from database.
- *
- * @param LedgerHeader: Ledger information.
- * @param app: Link to the Application.
- * @param acquire: Acquire the ledger if not found locally.
- * @return Shared pointer to the ledger.
- */
-std::shared_ptr<Ledger>
-loadLedgerHelper(LedgerHeader const& info, Application& app, bool acquire)
-{
-    bool loaded = false;
-    auto ledger = std::make_shared<Ledger>(
-        info, loaded, acquire, app.config(), app.getNodeFamily(), app.journal("Ledger"));
-
-    if (!loaded)
-        ledger.reset();
-
-    return ledger;
-}
-
-static void
-finishLoadByIndexOrHash(
-    std::shared_ptr<Ledger> const& ledger,
-    Config const& config,
-    beast::Journal j)
-{
-    if (!ledger)
-        return;
-
-    XRPL_ASSERT(
-        ledger->header().seq < XRP_LEDGER_EARLIEST_FEES || ledger->read(keylet::fees()),
-        "xrpl::finishLoadByIndexOrHash : valid ledger fees");
-    ledger->setImmutable();
-
-    JLOG(j.trace()) << "Loaded ledger: " << to_string(ledger->header().hash);
-
-    ledger->setFull();
-}
-
-std::tuple<std::shared_ptr<Ledger>, std::uint32_t, uint256>
-getLatestLedger(Application& app)
-{
-    std::optional<LedgerHeader> const info = app.getRelationalDatabase().getNewestLedgerInfo();
-    if (!info)
-        return {std::shared_ptr<Ledger>(), {}, {}};
-    return {loadLedgerHelper(*info, app, true), info->seq, info->hash};
-}
-
-std::shared_ptr<Ledger>
-loadByIndex(std::uint32_t ledgerIndex, Application& app, bool acquire)
-{
-    if (std::optional<LedgerHeader> info =
-            app.getRelationalDatabase().getLedgerInfoByIndex(ledgerIndex))
-    {
-        std::shared_ptr<Ledger> ledger = loadLedgerHelper(*info, app, acquire);
-        finishLoadByIndexOrHash(ledger, app.config(), app.journal("Ledger"));
-        return ledger;
-    }
-    return {};
-}
-
-std::shared_ptr<Ledger>
-loadByHash(uint256 const& ledgerHash, Application& app, bool acquire)
-{
-    if (std::optional<LedgerHeader> info =
-            app.getRelationalDatabase().getLedgerInfoByHash(ledgerHash))
-    {
-        std::shared_ptr<Ledger> ledger = loadLedgerHelper(*info, app, acquire);
-        finishLoadByIndexOrHash(ledger, app.config(), app.journal("Ledger"));
-        XRPL_ASSERT(
-            !ledger || ledger->header().hash == ledgerHash,
-            "xrpl::loadByHash : ledger hash match if loaded");
-        return ledger;
-    }
-    return {};
-}
 
 }  // namespace xrpl

src/libxrpl/ledger/PaymentSandbox.cpp

@@ -164,7 +164,7 @@ PaymentSandbox::balanceHook(
     auto delta = amount.zeroed();
     auto lastBal = amount;
     auto minBal = amount;
-    for (auto curSB = this; curSB; curSB = curSB->ps_)
+    for (auto curSB = this; curSB != nullptr; curSB = curSB->ps_)
     {
         if (auto adj = curSB->tab_.adjustments(account, issuer, currency))
         {
@@ -198,7 +198,7 @@ std::uint32_t
 PaymentSandbox::ownerCountHook(AccountID const& account, std::uint32_t count) const
 {
     std::uint32_t result = count;
-    for (auto curSB = this; curSB; curSB = curSB->ps_)
+    for (auto curSB = this; curSB != nullptr; curSB = curSB->ps_)
     {
         if (auto adj = curSB->tab_.ownerCount(account))
             result = std::max(result, *adj);

src/libxrpl/ledger/helpers/AccountRootHelpers.cpp

@@ -0,0 +1,247 @@
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+//
+#include <xrpl/basics/Log.h>
+#include <xrpl/beast/utility/instrumentation.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/digest.h>
+
+#include <algorithm>
+#include <limits>
+
+namespace xrpl {
+
+bool
+isGlobalFrozen(ReadView const& view, AccountID const& issuer)
+{
+    if (isXRP(issuer))
+        return false;
+    if (auto const sle = view.read(keylet::account(issuer)))
+        return sle->isFlag(lsfGlobalFreeze);
+    return false;
+}
+
+// An owner count cannot be negative. If adjustment would cause a negative
+// owner count, clamp the owner count at 0. Similarly for overflow. This
+// adjustment allows the ownerCount to be adjusted up or down in multiple steps.
+// If id != std::nullopt, then do error reporting.
+//
+// Returns adjusted owner count.
+static std::uint32_t
+confineOwnerCount(
+    std::uint32_t current,
+    std::int32_t adjustment,
+    std::optional<AccountID> const& id = std::nullopt,
+    beast::Journal j = beast::Journal{beast::Journal::getNullSink()})
+{
+    std::uint32_t adjusted{current + adjustment};
+    if (adjustment > 0)
+    {
+        // Overflow is well defined on unsigned
+        if (adjusted < current)
+        {
+            if (id)
+            {
+                JLOG(j.fatal()) << "Account " << *id << " owner count exceeds max!";
+            }
+            adjusted = std::numeric_limits<std::uint32_t>::max();
+        }
+    }
+    else
+    {
+        // Underflow is well defined on unsigned
+        if (adjusted > current)
+        {
+            if (id)
+            {
+                JLOG(j.fatal()) << "Account " << *id << " owner count set below 0!";
+            }
+            adjusted = 0;
+            XRPL_ASSERT(!id, "xrpl::confineOwnerCount : id is not set");
+        }
+    }
+    return adjusted;
+}
+
+XRPAmount
+xrpLiquid(ReadView const& view, AccountID const& id, std::int32_t ownerCountAdj, beast::Journal j)
+{
+    auto const sle = view.read(keylet::account(id));
+    if (sle == nullptr)
+        return beast::zero;
+
+    // Return balance minus reserve
+    std::uint32_t const ownerCount =
+        confineOwnerCount(view.ownerCountHook(id, sle->getFieldU32(sfOwnerCount)), ownerCountAdj);
+
+    // Pseudo-accounts have no reserve requirement
+    auto const reserve =
+        isPseudoAccount(sle) ? XRPAmount{0} : view.fees().accountReserve(ownerCount);
+
+    auto const fullBalance = sle->getFieldAmount(sfBalance);
+
+    auto const balance = view.balanceHook(id, xrpAccount(), fullBalance);
+
+    STAmount const amount = (balance < reserve) ? STAmount{0} : balance - reserve;
+
+    JLOG(j.trace()) << "accountHolds:" << " account=" << to_string(id)
+                    << " amount=" << amount.getFullText()
+                    << " fullBalance=" << fullBalance.getFullText()
+                    << " balance=" << balance.getFullText() << " reserve=" << reserve
+                    << " ownerCount=" << ownerCount << " ownerCountAdj=" << ownerCountAdj;
+
+    return amount.xrp();
+}
+
+Rate
+transferRate(ReadView const& view, AccountID const& issuer)
+{
+    auto const sle = view.read(keylet::account(issuer));
+
+    if (sle && sle->isFieldPresent(sfTransferRate))
+        return Rate{sle->getFieldU32(sfTransferRate)};
+
+    return parityRate;
+}
+
+void
+adjustOwnerCount(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sle,
+    std::int32_t amount,
+    beast::Journal j)
+{
+    if (!sle)
+        return;
+    XRPL_ASSERT(amount, "xrpl::adjustOwnerCount : nonzero amount input");
+    std::uint32_t const current{sle->getFieldU32(sfOwnerCount)};
+    AccountID const id = (*sle)[sfAccount];
+    std::uint32_t const adjusted = confineOwnerCount(current, amount, id, j);
+    view.adjustOwnerCountHook(id, current, adjusted);
+    sle->at(sfOwnerCount) = adjusted;
+    view.update(sle);
+}
+
+AccountID
+pseudoAccountAddress(ReadView const& view, uint256 const& pseudoOwnerKey)
+{
+    // This number must not be changed without an amendment
+    constexpr std::uint16_t maxAccountAttempts = 256;
+    for (std::uint16_t i = 0; i < maxAccountAttempts; ++i)
+    {
+        ripesha_hasher rsh;
+        auto const hash = sha512Half(i, view.header().parentHash, pseudoOwnerKey);
+        rsh(hash.data(), hash.size());
+        AccountID const ret{static_cast<ripesha_hasher::result_type>(rsh)};
+        if (!view.read(keylet::account(ret)))
+            return ret;
+    }
+    return beast::zero;
+}
+
+// Pseudo-account designator fields MUST be maintained by including the
+// SField::sMD_PseudoAccount flag in the SField definition. (Don't forget to
+// "| SField::sMD_Default"!) The fields do NOT need to be amendment-gated,
+// since a non-active amendment will not set any field, by definition.
+// Specific properties of a pseudo-account are NOT checked here, that's what
+// InvariantCheck is for.
+[[nodiscard]] std::vector<SField const*> const&
+getPseudoAccountFields()
+{
+    static std::vector<SField const*> const pseudoFields = []() {
+        auto const ar = LedgerFormats::getInstance().findByType(ltACCOUNT_ROOT);
+        if (!ar)
+        {
+            // LCOV_EXCL_START
+            LogicError(
+                "xrpl::getPseudoAccountFields : unable to find account root "
+                "ledger format");
+            // LCOV_EXCL_STOP
+        }
+        auto const& soTemplate = ar->getSOTemplate();
+
+        std::vector<SField const*> pseudoFields;
+        for (auto const& field : soTemplate)
+        {
+            if (field.sField().shouldMeta(SField::sMD_PseudoAccount))
+                pseudoFields.emplace_back(&field.sField());
+        }
+        return pseudoFields;
+    }();
+    return pseudoFields;
+}
+
+[[nodiscard]] bool
+isPseudoAccount(
+    std::shared_ptr<SLE const> sleAcct,
+    std::set<SField const*> const& pseudoFieldFilter)
+{
+    auto const& fields = getPseudoAccountFields();
+
+    // Intentionally use defensive coding here because it's cheap and makes the
+    // semantics of true return value clean.
+    return sleAcct && sleAcct->getType() == ltACCOUNT_ROOT &&
+        std::count_if(
+            fields.begin(), fields.end(), [&sleAcct, &pseudoFieldFilter](SField const* sf) -> bool {
+                return sleAcct->isFieldPresent(*sf) &&
+                    (pseudoFieldFilter.empty() || pseudoFieldFilter.contains(sf));
+            }) > 0;
+}
+
+Expected<std::shared_ptr<SLE>, TER>
+createPseudoAccount(ApplyView& view, uint256 const& pseudoOwnerKey, SField const& ownerField)
+{
+    [[maybe_unused]]
+    auto const& fields = getPseudoAccountFields();
+    XRPL_ASSERT(
+        std::count_if(
+            fields.begin(),
+            fields.end(),
+            [&ownerField](SField const* sf) -> bool { return *sf == ownerField; }) == 1,
+        "xrpl::createPseudoAccount : valid owner field");
+
+    auto const accountId = pseudoAccountAddress(view, pseudoOwnerKey);
+    if (accountId == beast::zero)
+        return Unexpected(tecDUPLICATE);
+
+    // Create pseudo-account.
+    auto account = std::make_shared<SLE>(keylet::account(accountId));
+    account->setAccountID(sfAccount, accountId);
+    account->setFieldAmount(sfBalance, STAmount{});
+
+    // Pseudo-accounts can't submit transactions, so set the sequence number
+    // to 0 to make them easier to spot and verify, and add an extra level
+    // of protection.
+    std::uint32_t const seqno =                           //
+        view.rules().enabled(featureSingleAssetVault) ||  //
+            view.rules().enabled(featureLendingProtocol)  //
+        ? 0                                               //
+        : view.seq();
+    account->setFieldU32(sfSequence, seqno);
+    // Ignore reserves requirement, disable the master key, allow default
+    // rippling, and enable deposit authorization to prevent payments into
+    // pseudo-account.
+    account->setFieldU32(sfFlags, lsfDisableMaster | lsfDefaultRipple | lsfDepositAuth);
+    // Link the pseudo-account with its owner object.
+    account->setFieldH256(ownerField, pseudoOwnerKey);
+
+    view.insert(account);
+
+    return account;
+}
+
+[[nodiscard]] TER
+checkDestinationAndTag(SLE::const_ref toSle, bool hasDestinationTag)
+{
+    if (toSle == nullptr)
+        return tecNO_DST;
+
+    // The tag is basically account-specific information we don't
+    // understand, but we can require someone to fill it in.
+    if (toSle->isFlag(lsfRequireDestTag) && !hasDestinationTag)
+        return tecDST_TAG_NEEDED;  // Cannot send without a tag
+
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/CredentialHelpers.cpp

@@ -1,5 +1,7 @@
-#include <xrpl/ledger/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+//
 #include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/digest.h>
 
@@ -76,7 +78,7 @@ deleteSLE(ApplyView& view, std::shared_ptr<SLE> const& sleCredential, beast::Jou
 
     auto const issuer = sleCredential->getAccountID(sfIssuer);
     auto const subject = sleCredential->getAccountID(sfSubject);
-    bool const accepted = sleCredential->getFlags() & lsfAccepted;
+    bool const accepted = (sleCredential->getFlags() & lsfAccepted) != 0u;
 
     auto err = delSLE(issuer, sfIssuerNode, !accepted || (subject == issuer));
     if (!isTesSuccess(err))
@@ -145,7 +147,7 @@ valid(STTx const& tx, ReadView const& view, AccountID const& src, beast::Journal
             return tecBAD_CREDENTIALS;
         }
 
-        if (!(sleCred->getFlags() & lsfAccepted))
+        if ((sleCred->getFlags() & lsfAccepted) == 0u)
         {
             JLOG(j.trace()) << "Credential isn't accepted. Cred: " << h;
             return tecBAD_CREDENTIALS;
@@ -186,7 +188,7 @@ validDomain(ReadView const& view, uint256 domainID, AccountID const& subject)
                 foundExpired = true;
                 continue;
             }
-            if (sleCredential->getFlags() & lsfAccepted)
+            if ((sleCredential->getFlags() & lsfAccepted) != 0u)
             {
                 return tesSUCCESS;
             }
@@ -307,7 +309,7 @@ verifyValidDomain(ApplyView& view, AccountID const& account, uint256 domainID, b
         if (!sleCredential)
             continue;  // expired, i.e. deleted in credentials::removeExpired
 
-        if (sleCredential->getFlags() & lsfAccepted)
+        if ((sleCredential->getFlags() & lsfAccepted) != 0u)
             return tesSUCCESS;
     }
 
@@ -334,7 +336,7 @@ verifyDepositPreauth(
     if (credentialsPresent && credentials::removeExpired(view, tx.getFieldV256(sfCredentialIDs), j))
         return tecEXPIRED;
 
-    if (sleDst && (sleDst->getFlags() & lsfDepositAuth))
+    if (sleDst && ((sleDst->getFlags() & lsfDepositAuth) != 0u))
     {
         if (src != dst)
         {

src/libxrpl/ledger/helpers/DirectoryHelpers.cpp

@@ -0,0 +1,177 @@
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+//
+#include <xrpl/protocol/LedgerFormats.h>
+
+namespace xrpl {
+
+bool
+dirFirst(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirFirst(view, root, page, index, entry);
+}
+
+bool
+dirNext(
+    ApplyView& view,
+    uint256 const& root,
+    std::shared_ptr<SLE>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirNext(view, root, page, index, entry);
+}
+
+bool
+cdirFirst(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirFirst(view, root, page, index, entry);
+}
+
+bool
+cdirNext(
+    ReadView const& view,
+    uint256 const& root,
+    std::shared_ptr<SLE const>& page,
+    unsigned int& index,
+    uint256& entry)
+{
+    return detail::internalDirNext(view, root, page, index, entry);
+}
+
+void
+forEachItem(
+    ReadView const& view,
+    Keylet const& root,
+    std::function<void(std::shared_ptr<SLE const> const&)> const& f)
+{
+    XRPL_ASSERT(root.type == ltDIR_NODE, "xrpl::forEachItem : valid root type");
+
+    if (root.type != ltDIR_NODE)
+        return;
+
+    auto pos = root;
+
+    while (true)
+    {
+        auto sle = view.read(pos);
+        if (!sle)
+            return;
+        for (auto const& key : sle->getFieldV256(sfIndexes))
+            f(view.read(keylet::child(key)));
+        auto const next = sle->getFieldU64(sfIndexNext);
+        if (next == 0u)
+            return;
+        pos = keylet::page(root, next);
+    }
+}
+
+bool
+forEachItemAfter(
+    ReadView const& view,
+    Keylet const& root,
+    uint256 const& after,
+    std::uint64_t const hint,
+    unsigned int limit,
+    std::function<bool(std::shared_ptr<SLE const> const&)> const& f)
+{
+    XRPL_ASSERT(root.type == ltDIR_NODE, "xrpl::forEachItemAfter : valid root type");
+
+    if (root.type != ltDIR_NODE)
+        return false;
+
+    auto currentIndex = root;
+
+    // If startAfter is not zero try jumping to that page using the hint
+    if (after.isNonZero())
+    {
+        auto const hintIndex = keylet::page(root, hint);
+
+        if (auto hintDir = view.read(hintIndex))
+        {
+            for (auto const& key : hintDir->getFieldV256(sfIndexes))
+            {
+                if (key == after)
+                {
+                    // We found the hint, we can start here
+                    currentIndex = hintIndex;
+                    break;
+                }
+            }
+        }
+
+        bool found = false;
+        for (;;)
+        {
+            auto const ownerDir = view.read(currentIndex);
+            if (!ownerDir)
+                return found;
+            for (auto const& key : ownerDir->getFieldV256(sfIndexes))
+            {
+                if (!found)
+                {
+                    if (key == after)
+                        found = true;
+                }
+                else if (f(view.read(keylet::child(key))) && limit-- <= 1)
+                {
+                    return found;
+                }
+            }
+
+            auto const uNodeNext = ownerDir->getFieldU64(sfIndexNext);
+            if (uNodeNext == 0)
+                return found;
+            currentIndex = keylet::page(root, uNodeNext);
+        }
+    }
+    else
+    {
+        for (;;)
+        {
+            auto const ownerDir = view.read(currentIndex);
+            if (!ownerDir)
+                return true;
+            for (auto const& key : ownerDir->getFieldV256(sfIndexes))
+            {
+                if (f(view.read(keylet::child(key))) && limit-- <= 1)
+                    return true;
+            }
+            auto const uNodeNext = ownerDir->getFieldU64(sfIndexNext);
+            if (uNodeNext == 0)
+                return true;
+            currentIndex = keylet::page(root, uNodeNext);
+        }
+    }
+}
+
+bool
+dirIsEmpty(ReadView const& view, Keylet const& k)
+{
+    auto const sleNode = view.read(k);
+    if (!sleNode)
+        return true;
+    if (!sleNode->getFieldV256(sfIndexes).empty())
+        return false;
+    // The first page of a directory may legitimately be empty even if there
+    // are other pages (the first page is the anchor page) so check to see if
+    // there is another page. If there is, the directory isn't empty.
+    return sleNode->getFieldU64(sfIndexNext) == 0;
+}
+
+std::function<void(SLE::ref)>
+describeOwnerDir(AccountID const& account)
+{
+    return [account](std::shared_ptr<SLE> const& sle) { (*sle)[sfOwner] = account; };
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/MPTokenHelpers.cpp

@@ -0,0 +1,752 @@
+#include <xrpl/ledger/helpers/MPTokenHelpers.h>
+//
+#include <xrpl/basics/Log.h>
+#include <xrpl/ledger/View.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/CredentialHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/TxFlags.h>
+
+namespace xrpl {
+
+bool
+isGlobalFrozen(ReadView const& view, MPTIssue const& mptIssue)
+{
+    if (auto const sle = view.read(keylet::mptIssuance(mptIssue.getMptID())))
+        return sle->isFlag(lsfMPTLocked);
+    return false;
+}
+
+bool
+isIndividualFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue)
+{
+    if (auto const sle = view.read(keylet::mptoken(mptIssue.getMptID(), account)))
+        return sle->isFlag(lsfMPTLocked);
+    return false;
+}
+
+bool
+isFrozen(ReadView const& view, AccountID const& account, MPTIssue const& mptIssue, int depth)
+{
+    return isGlobalFrozen(view, mptIssue) || isIndividualFrozen(view, account, mptIssue) ||
+        isVaultPseudoAccountFrozen(view, account, mptIssue, depth);
+}
+
+[[nodiscard]] bool
+isAnyFrozen(
+    ReadView const& view,
+    std::initializer_list<AccountID> const& accounts,
+    MPTIssue const& mptIssue,
+    int depth)
+{
+    if (isGlobalFrozen(view, mptIssue))
+        return true;
+
+    for (auto const& account : accounts)
+    {
+        if (isIndividualFrozen(view, account, mptIssue))
+            return true;
+    }
+
+    for (auto const& account : accounts)
+    {
+        if (isVaultPseudoAccountFrozen(view, account, mptIssue, depth))
+            return true;
+    }
+
+    return false;
+}
+
+Rate
+transferRate(ReadView const& view, MPTID const& issuanceID)
+{
+    // fee is 0-50,000 (0-50%), rate is 1,000,000,000-2,000,000,000
+    // For example, if transfer fee is 50% then 10,000 * 50,000 = 500,000
+    // which represents 50% of 1,000,000,000
+    if (auto const sle = view.read(keylet::mptIssuance(issuanceID));
+        sle && sle->isFieldPresent(sfTransferFee))
+        return Rate{1'000'000'000u + (10'000 * sle->getFieldU16(sfTransferFee))};
+
+    return parityRate;
+}
+
+[[nodiscard]] TER
+canAddHolding(ReadView const& view, MPTIssue const& mptIssue)
+{
+    auto mptID = mptIssue.getMptID();
+    auto issuance = view.read(keylet::mptIssuance(mptID));
+    if (!issuance)
+    {
+        return tecOBJECT_NOT_FOUND;
+    }
+    if (!issuance->isFlag(lsfMPTCanTransfer))
+    {
+        return tecNO_AUTH;
+    }
+
+    return tesSUCCESS;
+}
+
+[[nodiscard]] TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    MPTIssue const& mptIssue,
+    beast::Journal journal)
+{
+    auto const& mptID = mptIssue.getMptID();
+    auto const mpt = view.peek(keylet::mptIssuance(mptID));
+    if (!mpt)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+    if (mpt->isFlag(lsfMPTLocked))
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+    if (view.peek(keylet::mptoken(mptID, accountID)))
+        return tecDUPLICATE;
+    if (accountID == mptIssue.getIssuer())
+        return tesSUCCESS;
+
+    return authorizeMPToken(view, priorBalance, mptID, accountID, journal);
+}
+
+[[nodiscard]] TER
+authorizeMPToken(
+    ApplyView& view,
+    XRPAmount const& priorBalance,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    beast::Journal journal,
+    std::uint32_t flags,
+    std::optional<AccountID> holderID)
+{
+    auto const sleAcct = view.peek(keylet::account(account));
+    if (!sleAcct)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    // If the account that submitted the tx is a holder
+    // Note: `account_` is holder's account
+    //       `holderID` is NOT used
+    if (!holderID)
+    {
+        // When a holder wants to unauthorize/delete a MPT, the ledger must
+        //      - delete mptokenKey from owner directory
+        //      - delete the MPToken
+        if ((flags & tfMPTUnauthorize) != 0)
+        {
+            auto const mptokenKey = keylet::mptoken(mptIssuanceID, account);
+            auto const sleMpt = view.peek(mptokenKey);
+            if (!sleMpt || (*sleMpt)[sfMPTAmount] != 0)
+                return tecINTERNAL;  // LCOV_EXCL_LINE
+
+            if (!view.dirRemove(
+                    keylet::ownerDir(account), (*sleMpt)[sfOwnerNode], sleMpt->key(), false))
+                return tecINTERNAL;  // LCOV_EXCL_LINE
+
+            adjustOwnerCount(view, sleAcct, -1, journal);
+
+            view.erase(sleMpt);
+            return tesSUCCESS;
+        }
+
+        // A potential holder wants to authorize/hold a mpt, the ledger must:
+        //      - add the new mptokenKey to the owner directory
+        //      - create the MPToken object for the holder
+
+        // The reserve that is required to create the MPToken. Note
+        // that although the reserve increases with every item
+        // an account owns, in the case of MPTokens we only
+        // *enforce* a reserve if the user owns more than two
+        // items. This is similar to the reserve requirements of trust lines.
+        std::uint32_t const uOwnerCount = sleAcct->getFieldU32(sfOwnerCount);
+        XRPAmount const reserveCreate(
+            (uOwnerCount < 2) ? XRPAmount(beast::zero)
+                              : view.fees().accountReserve(uOwnerCount + 1));
+
+        if (priorBalance < reserveCreate)
+            return tecINSUFFICIENT_RESERVE;
+
+        // Defensive check before we attempt to create MPToken for the issuer
+        auto const mpt = view.read(keylet::mptIssuance(mptIssuanceID));
+        if (!mpt || mpt->getAccountID(sfIssuer) == account)
+        {
+            // LCOV_EXCL_START
+            UNREACHABLE("xrpl::authorizeMPToken : invalid issuance or issuers token");
+            if (view.rules().enabled(featureLendingProtocol))
+                return tecINTERNAL;
+            // LCOV_EXCL_STOP
+        }
+
+        auto const mptokenKey = keylet::mptoken(mptIssuanceID, account);
+        auto mptoken = std::make_shared<SLE>(mptokenKey);
+        if (auto ter = dirLink(view, account, mptoken))
+            return ter;  // LCOV_EXCL_LINE
+
+        (*mptoken)[sfAccount] = account;
+        (*mptoken)[sfMPTokenIssuanceID] = mptIssuanceID;
+        (*mptoken)[sfFlags] = 0;
+        view.insert(mptoken);
+
+        // Update owner count.
+        adjustOwnerCount(view, sleAcct, 1, journal);
+
+        return tesSUCCESS;
+    }
+
+    auto const sleMptIssuance = view.read(keylet::mptIssuance(mptIssuanceID));
+    if (!sleMptIssuance)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    // If the account that submitted this tx is the issuer of the MPT
+    // Note: `account_` is issuer's account
+    //       `holderID` is holder's account
+    if (account != (*sleMptIssuance)[sfIssuer])
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const sleMpt = view.peek(keylet::mptoken(mptIssuanceID, *holderID));
+    if (!sleMpt)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    std::uint32_t const flagsIn = sleMpt->getFieldU32(sfFlags);
+    std::uint32_t flagsOut = flagsIn;
+
+    // Issuer wants to unauthorize the holder, unset lsfMPTAuthorized on
+    // their MPToken
+    if ((flags & tfMPTUnauthorize) != 0)
+    {
+        flagsOut &= ~lsfMPTAuthorized;
+    }
+    // Issuer wants to authorize a holder, set lsfMPTAuthorized on their
+    // MPToken
+    else
+    {
+        flagsOut |= lsfMPTAuthorized;
+    }
+
+    if (flagsIn != flagsOut)
+        sleMpt->setFieldU32(sfFlags, flagsOut);
+
+    view.update(sleMpt);
+    return tesSUCCESS;
+}
+
+[[nodiscard]] TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    MPTIssue const& mptIssue,
+    beast::Journal journal)
+{
+    // If the account is the issuer, then no token should exist. MPTs do not
+    // have the legacy ability to create such a situation, but check anyway. If
+    // a token does exist, it will get deleted. If not, return success.
+    bool const accountIsIssuer = accountID == mptIssue.getIssuer();
+    auto const& mptID = mptIssue.getMptID();
+    auto const mptoken = view.peek(keylet::mptoken(mptID, accountID));
+    if (!mptoken)
+        return accountIsIssuer ? (TER)tesSUCCESS : (TER)tecOBJECT_NOT_FOUND;
+    // Unlike a trust line, if the account is the issuer, and the token has a
+    // balance, it can not just be deleted, because that will throw the issuance
+    // accounting out of balance, so fail. Since this should be impossible
+    // anyway, I'm not going to put any effort into it.
+    if (mptoken->at(sfMPTAmount) != 0)
+        return tecHAS_OBLIGATIONS;
+
+    return authorizeMPToken(
+        view,
+        {},  // priorBalance
+        mptID,
+        accountID,
+        journal,
+        tfMPTUnauthorize  // flags
+    );
+}
+
+[[nodiscard]] TER
+requireAuth(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& account,
+    AuthType authType,
+    int depth)
+{
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto const sleIssuance = view.read(mptID);
+    if (!sleIssuance)
+        return tecOBJECT_NOT_FOUND;
+
+    auto const mptIssuer = sleIssuance->getAccountID(sfIssuer);
+
+    // issuer is always "authorized"
+    if (mptIssuer == account)  // Issuer won't have MPToken
+        return tesSUCCESS;
+
+    bool const featureSAVEnabled = view.rules().enabled(featureSingleAssetVault);
+
+    if (featureSAVEnabled)
+    {
+        if (depth >= maxAssetCheckDepth)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        // requireAuth is recursive if the issuer is a vault pseudo-account
+        auto const sleIssuer = view.read(keylet::account(mptIssuer));
+        if (!sleIssuer)
+            return tefINTERNAL;  // LCOV_EXCL_LINE
+
+        if (sleIssuer->isFieldPresent(sfVaultID))
+        {
+            auto const sleVault = view.read(keylet::vault(sleIssuer->getFieldH256(sfVaultID)));
+            if (!sleVault)
+                return tefINTERNAL;  // LCOV_EXCL_LINE
+
+            auto const asset = sleVault->at(sfAsset);
+            if (auto const err = std::visit(
+                    [&]<ValidIssueType TIss>(TIss const& issue) {
+                        if constexpr (std::is_same_v<TIss, Issue>)
+                        {
+                            return requireAuth(view, issue, account, authType);
+                        }
+                        else
+                        {
+                            return requireAuth(view, issue, account, authType, depth + 1);
+                        }
+                    },
+                    asset.value());
+                !isTesSuccess(err))
+                return err;
+        }
+    }
+
+    auto const mptokenID = keylet::mptoken(mptID.key, account);
+    auto const sleToken = view.read(mptokenID);
+
+    // if account has no MPToken, fail
+    if (!sleToken && (authType == AuthType::StrongAuth || authType == AuthType::Legacy))
+        return tecNO_AUTH;
+
+    // Note, this check is not amendment-gated because DomainID will be always
+    // empty **unless** writing to it has been enabled by an amendment
+    auto const maybeDomainID = sleIssuance->at(~sfDomainID);
+    if (maybeDomainID)
+    {
+        XRPL_ASSERT(
+            sleIssuance->getFieldU32(sfFlags) & lsfMPTRequireAuth,
+            "xrpl::requireAuth : issuance requires authorization");
+        // ter = tefINTERNAL | tecOBJECT_NOT_FOUND | tecNO_AUTH | tecEXPIRED
+        auto const ter = credentials::validDomain(view, *maybeDomainID, account);
+        if (isTesSuccess(ter))
+        {
+            return ter;  // Note: sleToken might be null
+        }
+        if (!sleToken)
+        {
+            return ter;
+        }
+        // We ignore error from validDomain if we found sleToken, as it could
+        // belong to someone who is explicitly authorized e.g. a vault owner.
+    }
+
+    if (featureSAVEnabled)
+    {
+        // Implicitly authorize Vault and LoanBroker pseudo-accounts
+        if (isPseudoAccount(view, account, {&sfVaultID, &sfLoanBrokerID}))
+            return tesSUCCESS;
+    }
+
+    // mptoken must be authorized if issuance enabled requireAuth
+    if (sleIssuance->isFlag(lsfMPTRequireAuth) &&
+        (!sleToken || !sleToken->isFlag(lsfMPTAuthorized)))
+        return tecNO_AUTH;
+
+    return tesSUCCESS;  // Note: sleToken might be null
+}
+
+[[nodiscard]] TER
+enforceMPTokenAuthorization(
+    ApplyView& view,
+    MPTID const& mptIssuanceID,
+    AccountID const& account,
+    XRPAmount const& priorBalance,  // for MPToken authorization
+    beast::Journal j)
+{
+    auto const sleIssuance = view.read(keylet::mptIssuance(mptIssuanceID));
+    if (!sleIssuance)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    XRPL_ASSERT(
+        sleIssuance->isFlag(lsfMPTRequireAuth),
+        "xrpl::enforceMPTokenAuthorization : authorization required");
+
+    if (account == sleIssuance->at(sfIssuer))
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const keylet = keylet::mptoken(mptIssuanceID, account);
+    auto const sleToken = view.read(keylet);  //  NOTE: might be null
+    auto const maybeDomainID = sleIssuance->at(~sfDomainID);
+    bool expired = false;
+    bool const authorizedByDomain = [&]() -> bool {
+        // NOTE: defensive here, should be checked in preclaim
+        if (!maybeDomainID.has_value())
+            return false;  // LCOV_EXCL_LINE
+
+        auto const ter = verifyValidDomain(view, account, *maybeDomainID, j);
+        if (isTesSuccess(ter))
+            return true;
+        if (ter == tecEXPIRED)
+            expired = true;
+        return false;
+    }();
+
+    if (!authorizedByDomain && sleToken == nullptr)
+    {
+        // Could not find MPToken and won't create one, could be either of:
+        //
+        // 1. Field sfDomainID not set in MPTokenIssuance or
+        // 2. Account has no matching and accepted credentials or
+        // 3. Account has all expired credentials (deleted in verifyValidDomain)
+        //
+        // Either way, return tecNO_AUTH and there is nothing else to do
+        return expired ? tecEXPIRED : tecNO_AUTH;
+    }
+    if (!authorizedByDomain && maybeDomainID.has_value())
+    {
+        // Found an MPToken but the account is not authorized and we expect
+        // it to have been authorized by the domain. This could be because the
+        // credentials used to create the MPToken have expired or been deleted.
+        return expired ? tecEXPIRED : tecNO_AUTH;
+    }
+    if (!authorizedByDomain)
+    {
+        // We found an MPToken, but sfDomainID is not set, so this is a classic
+        // MPToken which requires authorization by the token issuer.
+        XRPL_ASSERT(
+            sleToken != nullptr && !maybeDomainID.has_value(),
+            "xrpl::enforceMPTokenAuthorization : found MPToken");
+        if (sleToken->isFlag(lsfMPTAuthorized))
+            return tesSUCCESS;
+
+        return tecNO_AUTH;
+    }
+    if (authorizedByDomain && sleToken != nullptr)
+    {
+        // Found an MPToken, authorized by the domain. Ignore authorization flag
+        // lsfMPTAuthorized because it is meaningless. Return tesSUCCESS
+        XRPL_ASSERT(
+            maybeDomainID.has_value(),
+            "xrpl::enforceMPTokenAuthorization : found MPToken for domain");
+        return tesSUCCESS;
+    }
+    if (authorizedByDomain)
+    {
+        // Could not find MPToken but there should be one because we are
+        // authorized by domain. Proceed to create it, then return tesSUCCESS
+        XRPL_ASSERT(
+            maybeDomainID.has_value() && sleToken == nullptr,
+            "xrpl::enforceMPTokenAuthorization : new MPToken for domain");
+        if (auto const err = authorizeMPToken(
+                view,
+                priorBalance,   // priorBalance
+                mptIssuanceID,  // mptIssuanceID
+                account,        // account
+                j);
+            !isTesSuccess(err))
+            return err;
+
+        return tesSUCCESS;
+    }
+
+    // LCOV_EXCL_START
+    UNREACHABLE("xrpl::enforceMPTokenAuthorization : condition list is incomplete");
+    return tefINTERNAL;
+    // LCOV_EXCL_STOP
+}
+
+TER
+canTransfer(
+    ReadView const& view,
+    MPTIssue const& mptIssue,
+    AccountID const& from,
+    AccountID const& to)
+{
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto const sleIssuance = view.read(mptID);
+    if (!sleIssuance)
+        return tecOBJECT_NOT_FOUND;
+
+    if (!sleIssuance->isFlag(lsfMPTCanTransfer))
+    {
+        if (from != (*sleIssuance)[sfIssuer] && to != (*sleIssuance)[sfIssuer])
+            return TER{tecNO_AUTH};
+    }
+    return tesSUCCESS;
+}
+
+TER
+rippleLockEscrowMPT(
+    ApplyView& view,
+    AccountID const& sender,
+    STAmount const& amount,
+    beast::Journal j)
+{
+    auto const mptIssue = amount.get<MPTIssue>();
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto sleIssuance = view.peek(mptID);
+    if (!sleIssuance)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleLockEscrowMPT: MPT issuance not found for "
+                        << mptIssue.getMptID();
+        return tecOBJECT_NOT_FOUND;
+    }  // LCOV_EXCL_STOP
+
+    if (amount.getIssuer() == sender)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleLockEscrowMPT: sender is the issuer, cannot lock MPTs.";
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+
+    // 1. Decrease the MPT Holder MPTAmount
+    // 2. Increase the MPT Holder EscrowedAmount
+    {
+        auto const mptokenID = keylet::mptoken(mptID.key, sender);
+        auto sle = view.peek(mptokenID);
+        if (!sle)
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: MPToken not found for " << sender;
+            return tecOBJECT_NOT_FOUND;
+        }  // LCOV_EXCL_STOP
+
+        auto const amt = sle->getFieldU64(sfMPTAmount);
+        auto const pay = amount.mpt().value();
+
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, amt), STAmount(mptIssue, pay)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: insufficient MPTAmount for "
+                            << to_string(sender) << ": " << amt << " < " << pay;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        (*sle)[sfMPTAmount] = amt - pay;
+
+        // Overflow check for addition
+        uint64_t const locked = (*sle)[~sfLockedAmount].value_or(0);
+
+        if (!canAdd(STAmount(mptIssue, locked), STAmount(mptIssue, pay)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: overflow on locked amount for "
+                            << to_string(sender) << ": " << locked << " + " << pay;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        if (sle->isFieldPresent(sfLockedAmount))
+        {
+            (*sle)[sfLockedAmount] += pay;
+        }
+        else
+        {
+            sle->setFieldU64(sfLockedAmount, pay);
+        }
+
+        view.update(sle);
+    }
+
+    // 1. Increase the Issuance EscrowedAmount
+    // 2. DO NOT change the Issuance OutstandingAmount
+    {
+        uint64_t const issuanceEscrowed = (*sleIssuance)[~sfLockedAmount].value_or(0);
+        auto const pay = amount.mpt().value();
+
+        // Overflow check for addition
+        if (!canAdd(STAmount(mptIssue, issuanceEscrowed), STAmount(mptIssue, pay)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleLockEscrowMPT: overflow on issuance "
+                               "locked amount for "
+                            << mptIssue.getMptID() << ": " << issuanceEscrowed << " + " << pay;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        if (sleIssuance->isFieldPresent(sfLockedAmount))
+        {
+            (*sleIssuance)[sfLockedAmount] += pay;
+        }
+        else
+        {
+            sleIssuance->setFieldU64(sfLockedAmount, pay);
+        }
+
+        view.update(sleIssuance);
+    }
+    return tesSUCCESS;
+}
+
+TER
+rippleUnlockEscrowMPT(
+    ApplyView& view,
+    AccountID const& sender,
+    AccountID const& receiver,
+    STAmount const& netAmount,
+    STAmount const& grossAmount,
+    beast::Journal j)
+{
+    if (!view.rules().enabled(fixTokenEscrowV1))
+    {
+        XRPL_ASSERT(
+            netAmount == grossAmount, "xrpl::rippleUnlockEscrowMPT : netAmount == grossAmount");
+    }
+
+    auto const& issuer = netAmount.getIssuer();
+    auto const& mptIssue = netAmount.get<MPTIssue>();
+    auto const mptID = keylet::mptIssuance(mptIssue.getMptID());
+    auto sleIssuance = view.peek(mptID);
+    if (!sleIssuance)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: MPT issuance not found for "
+                        << mptIssue.getMptID();
+        return tecOBJECT_NOT_FOUND;
+    }  // LCOV_EXCL_STOP
+
+    // Decrease the Issuance EscrowedAmount
+    {
+        if (!sleIssuance->isFieldPresent(sfLockedAmount))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: no locked amount in issuance for "
+                            << mptIssue.getMptID();
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        auto const locked = sleIssuance->getFieldU64(sfLockedAmount);
+        auto const redeem = grossAmount.mpt().value();
+
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, locked), STAmount(mptIssue, redeem)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient locked amount for "
+                            << mptIssue.getMptID() << ": " << locked << " < " << redeem;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        auto const newLocked = locked - redeem;
+        if (newLocked == 0)
+        {
+            sleIssuance->makeFieldAbsent(sfLockedAmount);
+        }
+        else
+        {
+            sleIssuance->setFieldU64(sfLockedAmount, newLocked);
+        }
+        view.update(sleIssuance);
+    }
+
+    if (issuer != receiver)
+    {
+        // Increase the MPT Holder MPTAmount
+        auto const mptokenID = keylet::mptoken(mptID.key, receiver);
+        auto sle = view.peek(mptokenID);
+        if (!sle)
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: MPToken not found for " << receiver;
+            return tecOBJECT_NOT_FOUND;
+        }  // LCOV_EXCL_STOP
+
+        auto current = sle->getFieldU64(sfMPTAmount);
+        auto delta = netAmount.mpt().value();
+
+        // Overflow check for addition
+        if (!canAdd(STAmount(mptIssue, current), STAmount(mptIssue, delta)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: overflow on MPTAmount for "
+                            << to_string(receiver) << ": " << current << " + " << delta;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        (*sle)[sfMPTAmount] += delta;
+        view.update(sle);
+    }
+    else
+    {
+        // Decrease the Issuance OutstandingAmount
+        auto const outstanding = sleIssuance->getFieldU64(sfOutstandingAmount);
+        auto const redeem = netAmount.mpt().value();
+
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, outstanding), STAmount(mptIssue, redeem)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient outstanding amount for "
+                            << mptIssue.getMptID() << ": " << outstanding << " < " << redeem;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        sleIssuance->setFieldU64(sfOutstandingAmount, outstanding - redeem);
+        view.update(sleIssuance);
+    }
+
+    if (issuer == sender)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: sender is the issuer, "
+                           "cannot unlock MPTs.";
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+    // Decrease the MPT Holder EscrowedAmount
+    auto const mptokenID = keylet::mptoken(mptID.key, sender);
+    auto sle = view.peek(mptokenID);
+    if (!sle)
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: MPToken not found for " << sender;
+        return tecOBJECT_NOT_FOUND;
+    }  // LCOV_EXCL_STOP
+
+    if (!sle->isFieldPresent(sfLockedAmount))
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: no locked amount in MPToken for "
+                        << to_string(sender);
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+
+    auto const locked = sle->getFieldU64(sfLockedAmount);
+    auto const delta = grossAmount.mpt().value();
+
+    // Underflow check for subtraction
+    if (!canSubtract(STAmount(mptIssue, locked), STAmount(mptIssue, delta)))
+    {  // LCOV_EXCL_START
+        JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient locked amount for "
+                        << to_string(sender) << ": " << locked << " < " << delta;
+        return tecINTERNAL;
+    }  // LCOV_EXCL_STOP
+
+    auto const newLocked = locked - delta;
+    if (newLocked == 0)
+    {
+        sle->makeFieldAbsent(sfLockedAmount);
+    }
+    else
+    {
+        sle->setFieldU64(sfLockedAmount, newLocked);
+    }
+    view.update(sle);
+
+    // Note: The gross amount is the amount that was locked, the net
+    // amount is the amount that is being unlocked. The difference is the fee
+    // that was charged for the transfer. If this difference is greater than
+    // zero, we need to update the outstanding amount.
+    auto const diff = grossAmount.mpt().value() - netAmount.mpt().value();
+    if (diff != 0)
+    {
+        auto const outstanding = sleIssuance->getFieldU64(sfOutstandingAmount);
+        // Underflow check for subtraction
+        if (!canSubtract(STAmount(mptIssue, outstanding), STAmount(mptIssue, diff)))
+        {  // LCOV_EXCL_START
+            JLOG(j.error()) << "rippleUnlockEscrowMPT: insufficient outstanding amount for "
+                            << mptIssue.getMptID() << ": " << outstanding << " < " << diff;
+            return tecINTERNAL;
+        }  // LCOV_EXCL_STOP
+
+        sleIssuance->setFieldU64(sfOutstandingAmount, outstanding - diff);
+        view.update(sleIssuance);
+    }
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/OfferHelpers.cpp

@@ -0,0 +1,58 @@
+#include <xrpl/ledger/helpers/OfferHelpers.h>
+//
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/st.h>
+
+namespace xrpl {
+
+TER
+offerDelete(ApplyView& view, std::shared_ptr<SLE> const& sle, beast::Journal j)
+{
+    if (!sle)
+        return tesSUCCESS;
+    auto offerIndex = sle->key();
+    auto owner = sle->getAccountID(sfAccount);
+
+    // Detect legacy directories.
+    uint256 uDirectory = sle->getFieldH256(sfBookDirectory);
+
+    if (!view.dirRemove(keylet::ownerDir(owner), sle->getFieldU64(sfOwnerNode), offerIndex, false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    if (!view.dirRemove(keylet::page(uDirectory), sle->getFieldU64(sfBookNode), offerIndex, false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    if (sle->isFieldPresent(sfAdditionalBooks))
+    {
+        XRPL_ASSERT(
+            sle->isFlag(lsfHybrid) && sle->isFieldPresent(sfDomainID),
+            "xrpl::offerDelete : should be a hybrid domain offer");
+
+        auto const& additionalBookDirs = sle->getFieldArray(sfAdditionalBooks);
+
+        for (auto const& bookDir : additionalBookDirs)
+        {
+            auto const& dirIndex = bookDir.getFieldH256(sfBookDirectory);
+            auto const& dirNode = bookDir.getFieldU64(sfBookNode);
+
+            if (!view.dirRemove(keylet::page(dirIndex), dirNode, offerIndex, false))
+            {
+                return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+            }
+        }
+    }
+
+    adjustOwnerCount(view, view.peek(keylet::account(owner)), -1, j);
+
+    view.erase(sle);
+
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/RippleStateHelpers.cpp

@@ -0,0 +1,760 @@
+#include <xrpl/ledger/helpers/RippleStateHelpers.h>
+//
+#include <xrpl/basics/Log.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/DirectoryHelpers.h>
+#include <xrpl/protocol/AmountConversions.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/Rules.h>
+
+namespace xrpl {
+
+//------------------------------------------------------------------------------
+//
+// Credit functions (from Credit.cpp)
+//
+//------------------------------------------------------------------------------
+
+STAmount
+creditLimit(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency)
+{
+    STAmount result(Issue{currency, account});
+
+    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
+
+    if (sleRippleState)
+    {
+        result = sleRippleState->getFieldAmount(account < issuer ? sfLowLimit : sfHighLimit);
+        result.setIssuer(account);
+    }
+
+    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditLimit : result issuer match");
+    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditLimit : result currency match");
+    return result;
+}
+
+IOUAmount
+creditLimit2(ReadView const& v, AccountID const& acc, AccountID const& iss, Currency const& cur)
+{
+    return toAmount<IOUAmount>(creditLimit(v, acc, iss, cur));
+}
+
+STAmount
+creditBalance(
+    ReadView const& view,
+    AccountID const& account,
+    AccountID const& issuer,
+    Currency const& currency)
+{
+    STAmount result(Issue{currency, account});
+
+    auto sleRippleState = view.read(keylet::line(account, issuer, currency));
+
+    if (sleRippleState)
+    {
+        result = sleRippleState->getFieldAmount(sfBalance);
+        if (account < issuer)
+            result.negate();
+        result.setIssuer(account);
+    }
+
+    XRPL_ASSERT(result.getIssuer() == account, "xrpl::creditBalance : result issuer match");
+    XRPL_ASSERT(result.getCurrency() == currency, "xrpl::creditBalance : result currency match");
+    return result;
+}
+
+//------------------------------------------------------------------------------
+//
+// Freeze checking (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+bool
+isIndividualFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer)
+{
+    if (isXRP(currency))
+        return false;
+    if (issuer != account)
+    {
+        // Check if the issuer froze the line
+        auto const sle = view.read(keylet::line(account, issuer, currency));
+        if (sle && sle->isFlag((issuer > account) ? lsfHighFreeze : lsfLowFreeze))
+            return true;
+    }
+    return false;
+}
+
+// Can the specified account spend the specified currency issued by
+// the specified issuer or does the freeze flag prohibit it?
+bool
+isFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer)
+{
+    if (isXRP(currency))
+        return false;
+    auto sle = view.read(keylet::account(issuer));
+    if (sle && sle->isFlag(lsfGlobalFreeze))
+        return true;
+    if (issuer != account)
+    {
+        // Check if the issuer froze the line
+        sle = view.read(keylet::line(account, issuer, currency));
+        if (sle && sle->isFlag((issuer > account) ? lsfHighFreeze : lsfLowFreeze))
+            return true;
+    }
+    return false;
+}
+
+bool
+isDeepFrozen(
+    ReadView const& view,
+    AccountID const& account,
+    Currency const& currency,
+    AccountID const& issuer)
+{
+    if (isXRP(currency))
+    {
+        return false;
+    }
+
+    if (issuer == account)
+    {
+        return false;
+    }
+
+    auto const sle = view.read(keylet::line(account, issuer, currency));
+    if (!sle)
+    {
+        return false;
+    }
+
+    return sle->isFlag(lsfHighDeepFreeze) || sle->isFlag(lsfLowDeepFreeze);
+}
+
+//------------------------------------------------------------------------------
+//
+// Trust line operations
+//
+//------------------------------------------------------------------------------
+
+TER
+trustCreate(
+    ApplyView& view,
+    bool const bSrcHigh,
+    AccountID const& uSrcAccountID,
+    AccountID const& uDstAccountID,
+    uint256 const& uIndex,      // --> ripple state entry
+    SLE::ref sleAccount,        // --> the account being set.
+    bool const bAuth,           // --> authorize account.
+    bool const bNoRipple,       // --> others cannot ripple through
+    bool const bFreeze,         // --> funds cannot leave
+    bool bDeepFreeze,           // --> can neither receive nor send funds
+    STAmount const& saBalance,  // --> balance of account being set.
+                                // Issuer should be noAccount()
+    STAmount const& saLimit,    // --> limit for account being set.
+                                // Issuer should be the account being set.
+    std::uint32_t uQualityIn,
+    std::uint32_t uQualityOut,
+    beast::Journal j)
+{
+    JLOG(j.trace()) << "trustCreate: " << to_string(uSrcAccountID) << ", "
+                    << to_string(uDstAccountID) << ", " << saBalance.getFullText();
+
+    auto const& uLowAccountID = !bSrcHigh ? uSrcAccountID : uDstAccountID;
+    auto const& uHighAccountID = bSrcHigh ? uSrcAccountID : uDstAccountID;
+    if (uLowAccountID == uHighAccountID)
+    {
+        // LCOV_EXCL_START
+        UNREACHABLE("xrpl::trustCreate : trust line to self");
+        if (view.rules().enabled(featureLendingProtocol))
+            return tecINTERNAL;
+        // LCOV_EXCL_STOP
+    }
+
+    auto const sleRippleState = std::make_shared<SLE>(ltRIPPLE_STATE, uIndex);
+    view.insert(sleRippleState);
+
+    auto lowNode = view.dirInsert(
+        keylet::ownerDir(uLowAccountID), sleRippleState->key(), describeOwnerDir(uLowAccountID));
+
+    if (!lowNode)
+        return tecDIR_FULL;  // LCOV_EXCL_LINE
+
+    auto highNode = view.dirInsert(
+        keylet::ownerDir(uHighAccountID), sleRippleState->key(), describeOwnerDir(uHighAccountID));
+
+    if (!highNode)
+        return tecDIR_FULL;  // LCOV_EXCL_LINE
+
+    bool const bSetDst = saLimit.getIssuer() == uDstAccountID;
+    bool const bSetHigh = bSrcHigh ^ bSetDst;
+
+    XRPL_ASSERT(sleAccount, "xrpl::trustCreate : non-null SLE");
+    if (!sleAccount)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    XRPL_ASSERT(
+        sleAccount->getAccountID(sfAccount) == (bSetHigh ? uHighAccountID : uLowAccountID),
+        "xrpl::trustCreate : matching account ID");
+    auto const slePeer = view.peek(keylet::account(bSetHigh ? uLowAccountID : uHighAccountID));
+    if (!slePeer)
+        return tecNO_TARGET;
+
+    // Remember deletion hints.
+    sleRippleState->setFieldU64(sfLowNode, *lowNode);
+    sleRippleState->setFieldU64(sfHighNode, *highNode);
+
+    sleRippleState->setFieldAmount(bSetHigh ? sfHighLimit : sfLowLimit, saLimit);
+    sleRippleState->setFieldAmount(
+        bSetHigh ? sfLowLimit : sfHighLimit,
+        STAmount(Issue{saBalance.getCurrency(), bSetDst ? uSrcAccountID : uDstAccountID}));
+
+    if (uQualityIn != 0u)
+        sleRippleState->setFieldU32(bSetHigh ? sfHighQualityIn : sfLowQualityIn, uQualityIn);
+
+    if (uQualityOut != 0u)
+        sleRippleState->setFieldU32(bSetHigh ? sfHighQualityOut : sfLowQualityOut, uQualityOut);
+
+    std::uint32_t uFlags = bSetHigh ? lsfHighReserve : lsfLowReserve;
+
+    if (bAuth)
+    {
+        uFlags |= (bSetHigh ? lsfHighAuth : lsfLowAuth);
+    }
+    if (bNoRipple)
+    {
+        uFlags |= (bSetHigh ? lsfHighNoRipple : lsfLowNoRipple);
+    }
+    if (bFreeze)
+    {
+        uFlags |= (bSetHigh ? lsfHighFreeze : lsfLowFreeze);
+    }
+    if (bDeepFreeze)
+    {
+        uFlags |= (bSetHigh ? lsfHighDeepFreeze : lsfLowDeepFreeze);
+    }
+
+    if ((slePeer->getFlags() & lsfDefaultRipple) == 0)
+    {
+        // The other side's default is no rippling
+        uFlags |= (bSetHigh ? lsfLowNoRipple : lsfHighNoRipple);
+    }
+
+    sleRippleState->setFieldU32(sfFlags, uFlags);
+    adjustOwnerCount(view, sleAccount, 1, j);
+
+    // ONLY: Create ripple balance.
+    sleRippleState->setFieldAmount(sfBalance, bSetHigh ? -saBalance : saBalance);
+
+    view.creditHook(uSrcAccountID, uDstAccountID, saBalance, saBalance.zeroed());
+
+    return tesSUCCESS;
+}
+
+TER
+trustDelete(
+    ApplyView& view,
+    std::shared_ptr<SLE> const& sleRippleState,
+    AccountID const& uLowAccountID,
+    AccountID const& uHighAccountID,
+    beast::Journal j)
+{
+    // Detect legacy dirs.
+    std::uint64_t uLowNode = sleRippleState->getFieldU64(sfLowNode);
+    std::uint64_t uHighNode = sleRippleState->getFieldU64(sfHighNode);
+
+    JLOG(j.trace()) << "trustDelete: Deleting ripple line: low";
+
+    if (!view.dirRemove(keylet::ownerDir(uLowAccountID), uLowNode, sleRippleState->key(), false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    JLOG(j.trace()) << "trustDelete: Deleting ripple line: high";
+
+    if (!view.dirRemove(keylet::ownerDir(uHighAccountID), uHighNode, sleRippleState->key(), false))
+    {
+        return tefBAD_LEDGER;  // LCOV_EXCL_LINE
+    }
+
+    JLOG(j.trace()) << "trustDelete: Deleting ripple line: state";
+    view.erase(sleRippleState);
+
+    return tesSUCCESS;
+}
+
+//------------------------------------------------------------------------------
+//
+// IOU issuance/redemption
+//
+//------------------------------------------------------------------------------
+
+static bool
+updateTrustLine(
+    ApplyView& view,
+    SLE::pointer state,
+    bool bSenderHigh,
+    AccountID const& sender,
+    STAmount const& before,
+    STAmount const& after,
+    beast::Journal j)
+{
+    if (!state)
+        return false;
+    std::uint32_t const flags(state->getFieldU32(sfFlags));
+
+    auto sle = view.peek(keylet::account(sender));
+    if (!sle)
+        return false;
+
+    // YYY Could skip this if rippling in reverse.
+    if (before > beast::zero
+        // Sender balance was positive.
+        && after <= beast::zero
+        // Sender is zero or negative.
+        && ((flags & (!bSenderHigh ? lsfLowReserve : lsfHighReserve)) != 0u)
+        // Sender reserve is set.
+        && static_cast<bool>(flags & (!bSenderHigh ? lsfLowNoRipple : lsfHighNoRipple)) !=
+            static_cast<bool>(sle->getFlags() & lsfDefaultRipple) &&
+        ((flags & (!bSenderHigh ? lsfLowFreeze : lsfHighFreeze)) == 0u) &&
+        !state->getFieldAmount(!bSenderHigh ? sfLowLimit : sfHighLimit)
+        // Sender trust limit is 0.
+        && (state->getFieldU32(!bSenderHigh ? sfLowQualityIn : sfHighQualityIn) == 0u)
+        // Sender quality in is 0.
+        && (state->getFieldU32(!bSenderHigh ? sfLowQualityOut : sfHighQualityOut) == 0u))
+    // Sender quality out is 0.
+    {
+        // VFALCO Where is the line being deleted?
+        // Clear the reserve of the sender, possibly delete the line!
+        adjustOwnerCount(view, sle, -1, j);
+
+        // Clear reserve flag.
+        state->setFieldU32(sfFlags, flags & (!bSenderHigh ? ~lsfLowReserve : ~lsfHighReserve));
+
+        // Balance is zero, receiver reserve is clear.
+        if (!after  // Balance is zero.
+            && ((flags & (bSenderHigh ? lsfLowReserve : lsfHighReserve)) == 0u))
+            return true;
+    }
+    return false;
+}
+
+TER
+issueIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j)
+{
+    XRPL_ASSERT(
+        !isXRP(account) && !isXRP(issue.account),
+        "xrpl::issueIOU : neither account nor issuer is XRP");
+
+    // Consistency check
+    XRPL_ASSERT(issue == amount.issue(), "xrpl::issueIOU : matching issue");
+
+    // Can't send to self!
+    XRPL_ASSERT(issue.account != account, "xrpl::issueIOU : not issuer account");
+
+    JLOG(j.trace()) << "issueIOU: " << to_string(account) << ": " << amount.getFullText();
+
+    bool bSenderHigh = issue.account > account;
+
+    auto const index = keylet::line(issue.account, account, issue.currency);
+
+    if (auto state = view.peek(index))
+    {
+        STAmount final_balance = state->getFieldAmount(sfBalance);
+
+        if (bSenderHigh)
+            final_balance.negate();  // Put balance in sender terms.
+
+        STAmount const start_balance = final_balance;
+
+        final_balance -= amount;
+
+        auto const must_delete = updateTrustLine(
+            view, state, bSenderHigh, issue.account, start_balance, final_balance, j);
+
+        view.creditHook(issue.account, account, amount, start_balance);
+
+        if (bSenderHigh)
+            final_balance.negate();
+
+        // Adjust the balance on the trust line if necessary. We do this even
+        // if we are going to delete the line to reflect the correct balance
+        // at the time of deletion.
+        state->setFieldAmount(sfBalance, final_balance);
+        if (must_delete)
+        {
+            return trustDelete(
+                view,
+                state,
+                bSenderHigh ? account : issue.account,
+                bSenderHigh ? issue.account : account,
+                j);
+        }
+
+        view.update(state);
+
+        return tesSUCCESS;
+    }
+
+    // NIKB TODO: The limit uses the receiver's account as the issuer and
+    // this is unnecessarily inefficient as copying which could be avoided
+    // is now required. Consider available options.
+    STAmount const limit(Issue{issue.currency, account});
+    STAmount final_balance = amount;
+
+    final_balance.setIssuer(noAccount());
+
+    auto const receiverAccount = view.peek(keylet::account(account));
+    if (!receiverAccount)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    bool noRipple = (receiverAccount->getFlags() & lsfDefaultRipple) == 0;
+
+    return trustCreate(
+        view,
+        bSenderHigh,
+        issue.account,
+        account,
+        index.key,
+        receiverAccount,
+        false,
+        noRipple,
+        false,
+        false,
+        final_balance,
+        limit,
+        0,
+        0,
+        j);
+}
+
+TER
+redeemIOU(
+    ApplyView& view,
+    AccountID const& account,
+    STAmount const& amount,
+    Issue const& issue,
+    beast::Journal j)
+{
+    XRPL_ASSERT(
+        !isXRP(account) && !isXRP(issue.account),
+        "xrpl::redeemIOU : neither account nor issuer is XRP");
+
+    // Consistency check
+    XRPL_ASSERT(issue == amount.issue(), "xrpl::redeemIOU : matching issue");
+
+    // Can't send to self!
+    XRPL_ASSERT(issue.account != account, "xrpl::redeemIOU : not issuer account");
+
+    JLOG(j.trace()) << "redeemIOU: " << to_string(account) << ": " << amount.getFullText();
+
+    bool bSenderHigh = account > issue.account;
+
+    if (auto state = view.peek(keylet::line(account, issue.account, issue.currency)))
+    {
+        STAmount final_balance = state->getFieldAmount(sfBalance);
+
+        if (bSenderHigh)
+            final_balance.negate();  // Put balance in sender terms.
+
+        STAmount const start_balance = final_balance;
+
+        final_balance -= amount;
+
+        auto const must_delete =
+            updateTrustLine(view, state, bSenderHigh, account, start_balance, final_balance, j);
+
+        view.creditHook(account, issue.account, amount, start_balance);
+
+        if (bSenderHigh)
+            final_balance.negate();
+
+        // Adjust the balance on the trust line if necessary. We do this even
+        // if we are going to delete the line to reflect the correct balance
+        // at the time of deletion.
+        state->setFieldAmount(sfBalance, final_balance);
+
+        if (must_delete)
+        {
+            return trustDelete(
+                view,
+                state,
+                bSenderHigh ? issue.account : account,
+                bSenderHigh ? account : issue.account,
+                j);
+        }
+
+        view.update(state);
+        return tesSUCCESS;
+    }
+
+    // In order to hold an IOU, a trust line *MUST* exist to track the
+    // balance. If it doesn't, then something is very wrong. Don't try
+    // to continue.
+    // LCOV_EXCL_START
+    JLOG(j.fatal()) << "redeemIOU: " << to_string(account) << " attempts to "
+                    << "redeem " << amount.getFullText() << " but no trust line exists!";
+
+    return tefINTERNAL;
+    // LCOV_EXCL_STOP
+}
+
+//------------------------------------------------------------------------------
+//
+// Authorization and transfer checks (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+TER
+requireAuth(ReadView const& view, Issue const& issue, AccountID const& account, AuthType authType)
+{
+    if (isXRP(issue) || issue.account == account)
+        return tesSUCCESS;
+
+    auto const trustLine = view.read(keylet::line(account, issue.account, issue.currency));
+    // If account has no line, and this is a strong check, fail
+    if (!trustLine && authType == AuthType::StrongAuth)
+        return tecNO_LINE;
+
+    // If this is a weak or legacy check, or if the account has a line, fail if
+    // auth is required and not set on the line
+    if (auto const issuerAccount = view.read(keylet::account(issue.account));
+        issuerAccount && (((*issuerAccount)[sfFlags] & lsfRequireAuth) != 0u))
+    {
+        if (trustLine)
+        {
+            return (((*trustLine)[sfFlags] &
+                     ((account > issue.account) ? lsfLowAuth : lsfHighAuth)) != 0u)
+                ? tesSUCCESS
+                : TER{tecNO_AUTH};
+        }
+        return TER{tecNO_LINE};
+    }
+
+    return tesSUCCESS;
+}
+
+TER
+canTransfer(ReadView const& view, Issue const& issue, AccountID const& from, AccountID const& to)
+{
+    if (issue.native())
+        return tesSUCCESS;
+
+    auto const& issuerId = issue.getIssuer();
+    if (issuerId == from || issuerId == to)
+        return tesSUCCESS;
+    auto const sleIssuer = view.read(keylet::account(issuerId));
+    if (sleIssuer == nullptr)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const isRippleDisabled = [&](AccountID account) -> bool {
+        // Line might not exist, but some transfers can create it. If this
+        // is the case, just check the default ripple on the issuer account.
+        auto const line = view.read(keylet::line(account, issue));
+        if (line)
+        {
+            bool const issuerHigh = issuerId > account;
+            return line->isFlag(issuerHigh ? lsfHighNoRipple : lsfLowNoRipple);
+        }
+        return !sleIssuer->isFlag(lsfDefaultRipple);
+    };
+
+    // Fail if rippling disabled on both trust lines
+    if (isRippleDisabled(from) && isRippleDisabled(to))
+        return terNO_RIPPLE;
+
+    return tesSUCCESS;
+}
+
+//------------------------------------------------------------------------------
+//
+// Empty holding operations (IOU-specific)
+//
+//------------------------------------------------------------------------------
+
+TER
+addEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    XRPAmount priorBalance,
+    Issue const& issue,
+    beast::Journal journal)
+{
+    // Every account can hold XRP. An issuer can issue directly.
+    if (issue.native() || accountID == issue.getIssuer())
+        return tesSUCCESS;
+
+    auto const& issuerId = issue.getIssuer();
+    auto const& currency = issue.currency;
+    if (isGlobalFrozen(view, issuerId))
+        return tecFROZEN;  // LCOV_EXCL_LINE
+
+    auto const& srcId = issuerId;
+    auto const& dstId = accountID;
+    auto const high = srcId > dstId;
+    auto const index = keylet::line(srcId, dstId, currency);
+    auto const sleSrc = view.peek(keylet::account(srcId));
+    auto const sleDst = view.peek(keylet::account(dstId));
+    if (!sleDst || !sleSrc)
+        return tefINTERNAL;  // LCOV_EXCL_LINE
+    if (!sleSrc->isFlag(lsfDefaultRipple))
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+    // If the line already exists, don't create it again.
+    if (view.read(index))
+        return tecDUPLICATE;
+
+    // Can the account cover the trust line reserve ?
+    std::uint32_t const ownerCount = sleDst->at(sfOwnerCount);
+    if (priorBalance < view.fees().accountReserve(ownerCount + 1))
+        return tecNO_LINE_INSUF_RESERVE;
+
+    return trustCreate(
+        view,
+        high,
+        srcId,
+        dstId,
+        index.key,
+        sleDst,
+        /*bAuth=*/false,
+        /*bNoRipple=*/true,
+        /*bFreeze=*/false,
+        /*deepFreeze*/ false,
+        /*saBalance=*/STAmount{Issue{currency, noAccount()}},
+        /*saLimit=*/STAmount{Issue{currency, dstId}},
+        /*uQualityIn=*/0,
+        /*uQualityOut=*/0,
+        journal);
+}
+
+TER
+removeEmptyHolding(
+    ApplyView& view,
+    AccountID const& accountID,
+    Issue const& issue,
+    beast::Journal journal)
+{
+    if (issue.native())
+    {
+        auto const sle = view.read(keylet::account(accountID));
+        if (!sle)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        auto const balance = sle->getFieldAmount(sfBalance);
+        if (balance.xrp() != 0)
+            return tecHAS_OBLIGATIONS;
+
+        return tesSUCCESS;
+    }
+
+    // `asset` is an IOU.
+    // If the account is the issuer, then no line should exist. Check anyway.
+    // If a line does exist, it will get deleted. If not, return success.
+    bool const accountIsIssuer = accountID == issue.account;
+    auto const line = view.peek(keylet::line(accountID, issue));
+    if (!line)
+        return accountIsIssuer ? (TER)tesSUCCESS : (TER)tecOBJECT_NOT_FOUND;
+    if (!accountIsIssuer && line->at(sfBalance)->iou() != beast::zero)
+        return tecHAS_OBLIGATIONS;
+
+    // Adjust the owner count(s)
+    if (line->isFlag(lsfLowReserve))
+    {
+        // Clear reserve for low account.
+        auto sleLowAccount = view.peek(keylet::account(line->at(sfLowLimit)->getIssuer()));
+        if (!sleLowAccount)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        adjustOwnerCount(view, sleLowAccount, -1, journal);
+        // It's not really necessary to clear the reserve flag, since the line
+        // is about to be deleted, but this will make the metadata reflect an
+        // accurate state at the time of deletion.
+        line->clearFlag(lsfLowReserve);
+    }
+
+    if (line->isFlag(lsfHighReserve))
+    {
+        // Clear reserve for high account.
+        auto sleHighAccount = view.peek(keylet::account(line->at(sfHighLimit)->getIssuer()));
+        if (!sleHighAccount)
+            return tecINTERNAL;  // LCOV_EXCL_LINE
+
+        adjustOwnerCount(view, sleHighAccount, -1, journal);
+        // It's not really necessary to clear the reserve flag, since the line
+        // is about to be deleted, but this will make the metadata reflect an
+        // accurate state at the time of deletion.
+        line->clearFlag(lsfHighReserve);
+    }
+
+    return trustDelete(
+        view, line, line->at(sfLowLimit)->getIssuer(), line->at(sfHighLimit)->getIssuer(), journal);
+}
+
+TER
+deleteAMMTrustLine(
+    ApplyView& view,
+    std::shared_ptr<SLE> sleState,
+    std::optional<AccountID> const& ammAccountID,
+    beast::Journal j)
+{
+    if (!sleState || sleState->getType() != ltRIPPLE_STATE)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    auto const& [low, high] = std::minmax(
+        sleState->getFieldAmount(sfLowLimit).getIssuer(),
+        sleState->getFieldAmount(sfHighLimit).getIssuer());
+    auto sleLow = view.peek(keylet::account(low));
+    auto sleHigh = view.peek(keylet::account(high));
+    if (!sleLow || !sleHigh)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    bool const ammLow = sleLow->isFieldPresent(sfAMMID);
+    bool const ammHigh = sleHigh->isFieldPresent(sfAMMID);
+
+    // can't both be AMM
+    if (ammLow && ammHigh)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    // at least one must be
+    if (!ammLow && !ammHigh)
+        return terNO_AMM;
+
+    // one must be the target amm
+    if (ammAccountID && (low != *ammAccountID && high != *ammAccountID))
+        return terNO_AMM;
+
+    if (auto const ter = trustDelete(view, sleState, low, high, j); !isTesSuccess(ter))
+    {
+        JLOG(j.error()) << "deleteAMMTrustLine: failed to delete the trustline.";
+        return ter;
+    }
+
+    auto const uFlags = !ammLow ? lsfLowReserve : lsfHighReserve;
+    if ((sleState->getFlags() & uFlags) == 0u)
+        return tecINTERNAL;  // LCOV_EXCL_LINE
+
+    adjustOwnerCount(view, !ammLow ? sleLow : sleHigh, -1, j);
+
+    return tesSUCCESS;
+}
+
+}  // namespace xrpl

src/libxrpl/ledger/helpers/VaultHelpers.cpp

@@ -0,0 +1,112 @@
+#include <xrpl/ledger/helpers/VaultHelpers.h>
+//
+#include <xrpl/basics/Number.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/st.h>
+
+namespace xrpl {
+
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets)
+{
+    XRPL_ASSERT(!assets.negative(), "xrpl::assetsToSharesDeposit : non-negative assets");
+    XRPL_ASSERT(
+        assets.asset() == vault->at(sfAsset),
+        "xrpl::assetsToSharesDeposit : assets and vault match");
+    if (assets.negative() || assets.asset() != vault->at(sfAsset))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number const assetTotal = vault->at(sfAssetsTotal);
+    STAmount shares{vault->at(sfShareMPTID)};
+    if (assetTotal == 0)
+    {
+        return STAmount{
+            shares.asset(),
+            Number(assets.mantissa(), assets.exponent() + vault->at(sfScale)).truncate()};
+    }
+
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    shares = ((shareTotal * assets) / assetTotal).truncate();
+    return shares;
+}
+
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsDeposit(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares)
+{
+    XRPL_ASSERT(!shares.negative(), "xrpl::sharesToAssetsDeposit : non-negative shares");
+    XRPL_ASSERT(
+        shares.asset() == vault->at(sfShareMPTID),
+        "xrpl::sharesToAssetsDeposit : shares and vault match");
+    if (shares.negative() || shares.asset() != vault->at(sfShareMPTID))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number const assetTotal = vault->at(sfAssetsTotal);
+    STAmount assets{vault->at(sfAsset)};
+    if (assetTotal == 0)
+    {
+        return STAmount{
+            assets.asset(), shares.mantissa(), shares.exponent() - vault->at(sfScale), false};
+    }
+
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    assets = (assetTotal * shares) / shareTotal;
+    return assets;
+}
+
+[[nodiscard]] std::optional<STAmount>
+assetsToSharesWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& assets,
+    TruncateShares truncate)
+{
+    XRPL_ASSERT(!assets.negative(), "xrpl::assetsToSharesWithdraw : non-negative assets");
+    XRPL_ASSERT(
+        assets.asset() == vault->at(sfAsset),
+        "xrpl::assetsToSharesWithdraw : assets and vault match");
+    if (assets.negative() || assets.asset() != vault->at(sfAsset))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number assetTotal = vault->at(sfAssetsTotal);
+    assetTotal -= vault->at(sfLossUnrealized);
+    STAmount shares{vault->at(sfShareMPTID)};
+    if (assetTotal == 0)
+        return shares;
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    Number result = (shareTotal * assets) / assetTotal;
+    if (truncate == TruncateShares::yes)
+        result = result.truncate();
+    shares = result;
+    return shares;
+}
+
+[[nodiscard]] std::optional<STAmount>
+sharesToAssetsWithdraw(
+    std::shared_ptr<SLE const> const& vault,
+    std::shared_ptr<SLE const> const& issuance,
+    STAmount const& shares)
+{
+    XRPL_ASSERT(!shares.negative(), "xrpl::sharesToAssetsWithdraw : non-negative shares");
+    XRPL_ASSERT(
+        shares.asset() == vault->at(sfShareMPTID),
+        "xrpl::sharesToAssetsWithdraw : shares and vault match");
+    if (shares.negative() || shares.asset() != vault->at(sfShareMPTID))
+        return std::nullopt;  // LCOV_EXCL_LINE
+
+    Number assetTotal = vault->at(sfAssetsTotal);
+    assetTotal -= vault->at(sfLossUnrealized);
+    STAmount assets{vault->at(sfAsset)};
+    if (assetTotal == 0)
+        return assets;
+    Number const shareTotal = issuance->at(sfOutstandingAmount);
+    assets = (assetTotal * shares) / shareTotal;
+    return assets;
+}
+
+}  // namespace xrpl

src/libxrpl/net/HTTPClient.cpp

@@ -59,6 +59,7 @@ public:
     //--------------------------------------------------------------------------
 
     void
+    // NOLINTNEXTLINE(readability-convert-member-functions-to-static)
     makeGet(std::string const& strPath, boost::asio::streambuf& sb, std::string const& strHost)
     {
         std::ostream osRequest(&sb);

src/libxrpl/nodestore/ManagerImp.cpp

@@ -55,7 +55,7 @@ ManagerImp::make_Backend(
         missing_backend();
 
     auto factory{find(type)};
-    if (!factory)
+    if (factory == nullptr)
     {
         missing_backend();
     }

src/libxrpl/nodestore/backend/RocksDBFactory.cpp

@@ -213,7 +213,7 @@ public:
         rocksdb::DB* db = nullptr;
         m_options.create_if_missing = createIfMissing;
         rocksdb::Status status = rocksdb::DB::Open(m_options, m_name, &db);
-        if (!status.ok() || !db)
+        if (!status.ok() || (db == nullptr))
         {
             Throw<std::runtime_error>(
                 std::string("Unable to open/create RocksDB: ") + status.ToString());

src/libxrpl/protocol/BuildInfo.cpp

@@ -140,7 +140,7 @@ encodeSoftwareVersion(std::string_view versionStr)
                 if (x == 0)
                     x = parsePreRelease(id, "b", 0x40, 0, 63);
 
-                if (x & 0xC0)
+                if ((x & 0xC0) != 0)
                 {
                     c |= static_cast<std::uint64_t>(x) << 16;
                     break;

src/libxrpl/protocol/ErrorCodes.cpp

@@ -205,9 +205,7 @@ make_error(error_code_i code, std::string const& message)
 bool
 contains_error(Json::Value const& json)
 {
-    if (json.isObject() && json.isMember(jss::error))
-        return true;
-    return false;
+    return json.isObject() && json.isMember(jss::error);
 }
 
 int

src/libxrpl/protocol/Feature.cpp

@@ -209,7 +209,7 @@ FeatureCollections::getRegisteredFeature(std::string const& name) const
     XRPL_ASSERT(
         readOnly.load(), "xrpl::FeatureCollections::getRegisteredFeature : startup completed");
     Feature const* feature = getByName(name);
-    if (feature)
+    if (feature != nullptr)
         return feature->feature;
     return std::nullopt;
 }
@@ -229,7 +229,7 @@ FeatureCollections::registerFeature(std::string const& name, Supported support,
         support == Supported::yes || vote == VoteBehavior::DefaultNo,
         "Invalid feature parameters. Must be supported to be up-voted.");
     Feature const* i = getByName(name);
-    if (!i)
+    if (i == nullptr)
     {
         check(features.size() < detail::numFeatures, "More features defined than allocated.");
 
@@ -283,7 +283,7 @@ FeatureCollections::featureToBitsetIndex(uint256 const& f) const
         readOnly.load(), "xrpl::FeatureCollections::featureToBitsetIndex : startup completed");
 
     Feature const* feature = getByFeature(f);
-    if (!feature)
+    if (feature == nullptr)
         LogicError("Invalid Feature ID");
 
     return getIndex(*feature);
@@ -303,7 +303,7 @@ FeatureCollections::featureToName(uint256 const& f) const
 {
     XRPL_ASSERT(readOnly.load(), "xrpl::FeatureCollections::featureToName : startup completed");
     Feature const* feature = getByFeature(f);
-    return feature ? feature->name : to_string(f);
+    return (feature != nullptr) ? feature->name : to_string(f);
 }
 
 FeatureCollections featureCollections;

src/libxrpl/protocol/IOUAmount.cpp

@@ -186,7 +186,7 @@ mulRatio(IOUAmount const& amt, std::uint32_t num, std::uint32_t den, bool roundU
 {
     using namespace boost::multiprecision;
 
-    if (!den)
+    if (den == 0u)
         Throw<std::runtime_error>("division by zero");
 
     // A vector with the value 10^index for indexes from 0 to 29

src/libxrpl/protocol/InnerObjectFormats.cpp

@@ -172,7 +172,7 @@ SOTemplate const*
 InnerObjectFormats::findSOTemplateBySField(SField const& sField) const
 {
     auto itemPtr = findByType(sField.getCode());
-    if (itemPtr)
+    if (itemPtr != nullptr)
         return &(itemPtr->getSOTemplate());
 
     return nullptr;

src/libxrpl/protocol/LedgerHeader.cpp

@@ -1,7 +1,9 @@
 #include <xrpl/basics/Slice.h>
 #include <xrpl/basics/chrono.h>
+#include <xrpl/protocol/HashPrefix.h>
 #include <xrpl/protocol/LedgerHeader.h>
 #include <xrpl/protocol/Serializer.h>
+#include <xrpl/protocol/digest.h>
 
 namespace xrpl {
 
@@ -51,4 +53,21 @@ deserializePrefixedHeader(Slice data, bool hasHash)
     return deserializeHeader(data + 4, hasHash);
 }
 
+uint256
+calculateLedgerHash(LedgerHeader const& info)
+{
+    // VFALCO This has to match addRaw in View.h.
+    return sha512Half(
+        HashPrefix::ledgerMaster,
+        std::uint32_t(info.seq),
+        std::uint64_t(info.drops.drops()),
+        info.parentHash,
+        info.txHash,
+        info.accountHash,
+        std::uint32_t(info.parentCloseTime.time_since_epoch().count()),
+        std::uint32_t(info.closeTime.time_since_epoch().count()),
+        std::uint8_t(info.closeTimeResolution.count()),
+        std::uint8_t(info.closeFlags));
+}
+
 }  // namespace xrpl

src/libxrpl/protocol/NFTokenOfferID.cpp

@@ -24,7 +24,7 @@ canHaveNFTokenOfferID(
         return false;
 
     TxType const tt = serializedTx->getTxnType();
-    if (!(tt == ttNFTOKEN_MINT && serializedTx->isFieldPresent(sfAmount)) &&
+    if ((tt != ttNFTOKEN_MINT || !serializedTx->isFieldPresent(sfAmount)) &&
         tt != ttNFTOKEN_CREATE_OFFER)
         return false;
 

src/libxrpl/protocol/Permissions.cpp

@@ -176,13 +176,13 @@ Permission::isDelegable(std::uint32_t const& permissionValue, Rules const& rules
 }
 
 uint32_t
-Permission::txToPermissionType(TxType const& type) const
+Permission::txToPermissionType(TxType const& type)
 {
     return static_cast<uint32_t>(type) + 1;
 }
 
 TxType
-Permission::permissionToTxType(uint32_t const& value) const
+Permission::permissionToTxType(uint32_t const& value)
 {
     return static_cast<TxType>(value - 1);
 }

src/libxrpl/protocol/PublicKey.cpp

@@ -75,7 +75,7 @@ static std::string
 sliceToHex(Slice const& slice)
 {
     std::string s;
-    if (slice[0] & 0x80)
+    if ((slice[0] & 0x80) != 0)
     {
         s.reserve(2 * (slice.size() + 2));
         s = "0x00";

src/libxrpl/protocol/STAccount.cpp

@@ -84,7 +84,7 @@ bool
 STAccount::isEquivalent(STBase const& t) const
 {
     auto const* const tPtr = dynamic_cast<STAccount const*>(&t);
-    return tPtr && (default_ == tPtr->default_) && (value_ == tPtr->value_);
+    return (tPtr != nullptr) && (default_ == tPtr->default_) && (value_ == tPtr->value_);
 }
 
 bool

src/libxrpl/protocol/STAmount.cpp

@@ -152,7 +152,7 @@ STAmount::STAmount(SerialIter& sit, SField const& name) : STBase(name)
 
     value &= ~(1023ull << (64 - 10));
 
-    if (value)
+    if (value != 0u)
     {
         bool isNegative = (offset & 256) == 0;
         offset = (offset & 255) - 97;  // center the range
@@ -505,14 +505,11 @@ canAdd(STAmount const& a, STAmount const& b)
         XRPAmount A = a.xrp();
         XRPAmount B = b.xrp();
 
-        if ((B > XRPAmount{0} &&
+        return !(
+            (B > XRPAmount{0} &&
              A > XRPAmount{std::numeric_limits<XRPAmount::value_type>::max()} - B) ||
             (B < XRPAmount{0} &&
-             A < XRPAmount{std::numeric_limits<XRPAmount::value_type>::min()} - B))
-        {
-            return false;
-        }
-        return true;
+             A < XRPAmount{std::numeric_limits<XRPAmount::value_type>::min()} - B));
     }
 
     // IOU case (precision check)
@@ -530,15 +527,11 @@ canAdd(STAmount const& a, STAmount const& b)
     {
         MPTAmount A = a.mpt();
         MPTAmount B = b.mpt();
-        if ((B > MPTAmount{0} &&
+        return !(
+            (B > MPTAmount{0} &&
              A > MPTAmount{std::numeric_limits<MPTAmount::value_type>::max()} - B) ||
             (B < MPTAmount{0} &&
-             A < MPTAmount{std::numeric_limits<MPTAmount::value_type>::min()} - B))
-        {
-            return false;
-        }
-
-        return true;
+             A < MPTAmount{std::numeric_limits<MPTAmount::value_type>::min()} - B));
     }
     // LCOV_EXCL_START
     UNREACHABLE("STAmount::canAdd : unexpected STAmount type");
@@ -803,7 +796,7 @@ bool
 STAmount::isEquivalent(STBase const& t) const
 {
     STAmount const* v = dynamic_cast<STAmount const*>(&t);
-    return v && (*v == *this);
+    return (v != nullptr) && (*v == *this);
 }
 
 bool

src/libxrpl/protocol/STBlob.cpp

@@ -53,7 +53,7 @@ bool
 STBlob::isEquivalent(STBase const& t) const
 {
     STBlob const* v = dynamic_cast<STBlob const*>(&t);
-    return v && (value_ == v->value_);
+    return (v != nullptr) && (value_ == v->value_);
 }
 
 bool

src/libxrpl/protocol/STCurrency.cpp

@@ -56,7 +56,7 @@ bool
 STCurrency::isEquivalent(STBase const& t) const
 {
     STCurrency const* v = dynamic_cast<STCurrency const*>(&t);
-    return v && (*v == *this);
+    return (v != nullptr) && (*v == *this);
 }
 
 bool