Simplify protobuf generation

Builds/CMake/RippledCore.cmake

@@ -3,10 +3,55 @@
    core functionality, useable by some client software perhaps
 #]===================================================================]
 
+include(target_protobuf_sources)
+
 file (GLOB_RECURSE rb_headers
   src/ripple/beast/*.h
   src/ripple/beast/*.hpp)
 
+# Protocol buffers cannot participate in a unity build,
+# because all the generated sources
+# define a bunch of `static const` variables with the same names,
+# so we just build them as a separate library.
+add_library(xrpl.libpb)
+target_protobuf_sources(xrpl.libpb ripple/proto
+  LANGUAGE cpp
+  IMPORT_DIRS src/ripple/proto
+  PROTOS src/ripple/proto/ripple.proto
+)
+
+file(GLOB_RECURSE protos "src/ripple/proto/org/*.proto")
+target_protobuf_sources(xrpl.libpb ripple/proto
+  LANGUAGE cpp
+  IMPORT_DIRS src/ripple/proto
+  PROTOS "${protos}"
+)
+target_protobuf_sources(xrpl.libpb ripple/proto
+  LANGUAGE grpc
+  IMPORT_DIRS src/ripple/proto
+  PROTOS "${protos}"
+  PLUGIN protoc-gen-grpc=$<TARGET_FILE:gRPC::grpc_cpp_plugin>
+  GENERATE_EXTENSIONS .grpc.pb.h .grpc.pb.cc
+)
+
+target_compile_options(xrpl.libpb
+  PUBLIC
+    $<$<BOOL:${MSVC}>:-wd4996>
+    $<$<BOOL:${XCODE}>:
+      --system-header-prefix="google/protobuf"
+      -Wno-deprecated-dynamic-exception-spec
+    >
+  PRIVATE
+    $<$<BOOL:${MSVC}>:-wd4065>
+    $<$<NOT:$<BOOL:${MSVC}>>:-Wno-deprecated-declarations>
+)
+
+target_link_libraries(xrpl.libpb
+  PUBLIC
+    protobuf::libprotobuf
+    gRPC::grpc++
+)
+
 add_library (xrpl_core
   ${rb_headers}) ## headers added here for benefit of IDEs
 if (unity)
@@ -27,7 +72,6 @@ add_library(libxrpl INTERFACE)
 target_link_libraries(libxrpl INTERFACE xrpl_core)
 add_library(xrpl::libxrpl ALIAS libxrpl)
 
-
 #[===============================[
     beast/legacy FILES:
     TODO: review these sources for removal or replacement
@@ -165,6 +209,7 @@ target_link_libraries (xrpl_core
     Ripple::syslibs
     secp256k1::secp256k1
     ed25519::ed25519
+    xrpl.libpb
     date::date
     Ripple::opts
     xxHash::xxhash)

Builds/CMake/RippledInstall.cmake

@@ -9,6 +9,7 @@ install (
     ripple_syslibs
     ripple_boost
     xrpl_core
+    xrpl.libpb
   EXPORT RippleExports
   LIBRARY DESTINATION lib
   ARCHIVE DESTINATION lib

Builds/CMake/target_protobuf_sources.cmake

@@ -0,0 +1,62 @@
+find_package(Protobuf REQUIRED)
+
+# .proto files import each other like this:
+#
+# import "path/to/file.proto";
+#
+# For the protobuf compiler to find these imports,
+# the parent directory of "path" must be in the import path.
+#
+# When generating C++,
+# it turns into an include statement like this:
+#
+# #include "path/to/file.pb.h"
+#
+# and the header is generated at a path relative to the output directory
+# that matches the given .proto path relative to the source directory
+# minus the first matching prefix on the import path.
+#
+# In other words, a file `include/package/path/to/file.proto`
+# with import path [`include/package`, `include`]
+# will generate files `output/path/to/file.pb.{h,cc}`
+# with includes like `#include "path/to/file.pb.h".
+#
+# During build, the generated files can find each other if the output
+# directory is an include directory, but we want to install that directory
+# under our package's include directory (`include/package`), not as a sibling.
+# After install, they can find each other if that subdirectory is an include
+# directory.
+
+# Add protocol buffer sources to an existing library target.
+# target:
+#     The name of the library target.
+# prefix:
+#     The install prefix for headers relative to `CMAKE_INSTALL_INCLUDEDIR`.
+#     This prefix should appear at the start of all your consumer includes.
+# ARGN:
+#     A list of .proto files.
+function(target_protobuf_sources target prefix)
+  set(dir "${CMAKE_CURRENT_BINARY_DIR}/pb-${target}")
+  file(MAKE_DIRECTORY "${dir}/${prefix}")
+
+  protobuf_generate(
+    TARGET ${target}
+    PROTOC_OUT_DIR "${dir}/${prefix}"
+    "${ARGN}"
+  )
+  target_include_directories(${target} SYSTEM PUBLIC
+    # Allows #include <package/path/to/file.proto> used by consumer files.
+    $<BUILD_INTERFACE:${dir}>
+    # Allows #include "path/to/file.proto" used by generated files.
+    $<BUILD_INTERFACE:${dir}/${prefix}>
+    # Allows #include <package/path/to/file.proto> used by consumer files.
+    $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
+    # Allows #include "path/to/file.proto" used by generated files.
+    $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/${prefix}>
+  )
+  install(
+    DIRECTORY ${dir}/
+    DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+    FILES_MATCHING PATTERN "*.h"
+  )
+endfunction()

CMakeLists.txt

@@ -90,8 +90,9 @@ set_target_properties(OpenSSL::SSL PROPERTIES
 )
 set(SECP256K1_INSTALL TRUE)
 add_subdirectory(external/secp256k1)
-add_subdirectory(external/ed25519-donna)
 add_library(secp256k1::secp256k1 ALIAS secp256k1)
+add_subdirectory(external/ed25519-donna)
+find_package(gRPC REQUIRED)
 find_package(lz4 REQUIRED)
 # Target names with :: are not allowed in a generator expression.
 # We need to pull the include directories and imported location properties

conanfile.py

@@ -32,12 +32,15 @@ class Xrpl(ConanFile):
         'lz4/1.9.4',
         'nudb/2.0.8',
         'openssl/3.6.0',
-        'protobuf/3.21.12',
         'soci/4.0.3@xahaud/stable',
         'xxhash/0.8.2',
         'zlib/1.3.1',
     ]
 
+    tool_requires = [
+        'protobuf/3.21.12',
+    ]
+
     default_options = {
         'assertions': False,
         'coverage': False,
@@ -101,7 +104,6 @@ class Xrpl(ConanFile):
 
     def build_requirements(self):
         # These provide build tools (protoc, grpc plugins) that run during build
-        self.tool_requires('protobuf/3.21.12')
         self.tool_requires('grpc/1.50.1')
         # Explicitly require b2 (e.g. for building from source for glibc compatibility)
         if self.options.tool_requires_b2: