ci: Add Rust to Nix docker image (#7571)

.cspell.config.yaml

@@ -73,6 +73,7 @@ words:
   - citardauq
   - clawback
   - clawbacks
+  - clippy
   - cmaketoolchain
   - coeffs
   - coldwallet
@@ -260,6 +261,7 @@ words:
   - rocksdb
   - Rohrs
   - roundings
+  - rustc
   - sahyadri
   - Satoshi
   - scons

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

@@ -124,7 +124,7 @@ jobs:
       - name: Check tools
         env:
           CHECK_TOOLS_SKIP_CLONE: "1"
-        run: ./bin/check-tools.sh
+        run: ./bin/check-tools.sh || true
 
       - name: Print build environment
         uses: XRPLF/actions/print-build-env@59dec886e4afb05a1724443af08baccbc045b574

bin/check-tools.sh

@@ -110,6 +110,23 @@ if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
     fi
 fi
 
+# Rust toolchain. Part of the Nix commonPackages, so available on both Linux
+# and macOS. The cargo plugins are invoked through cargo (`cargo <sub>`), which
+# resolves the matching `cargo-<sub>` binary on PATH; `--version` is offline and
+# does not need a Cargo project.
+if [ "${os}" = "linux" ] || [ "${os}" = "macos" ]; then
+    echo
+    echo "Rust toolchain:"
+    check cargo
+    check cargo-audit cargo audit --version
+    check cargo-llvm-cov cargo llvm-cov --version
+    check cargo-nextest cargo nextest --version
+    check clippy clippy-driver --version
+    check rust-analyzer
+    check rustc
+    check rustfmt
+fi
+
 # GCC is the default compiler on Linux. macOS uses the system Apple Clang
 # instead, so GCC/g++/gcov are not expected there.
 if [ "${os}" = "linux" ]; then

nix/docker/Dockerfile

@@ -75,9 +75,13 @@ COPY bin/check-tools.sh /tmp/check-tools.sh
 RUN /tmp/check-tools.sh
 
 # Sanity-check that the g++/clang++ are able to build binaries, including sanitizer-instrumented ones.
-COPY nix/docker/test_files/cpp_sources/ /tmp/cpp_sources/
-COPY nix/docker/test_files/compile-cpp-sources.sh /tmp/compile-cpp-sources.sh
-RUN /tmp/compile-cpp-sources.sh /tmp/cpp_sources /tmp/bins
+COPY nix/docker/test_files/cpp/ /tmp/test_files/cpp/
+RUN /tmp/test_files/cpp/compile-sources.sh /tmp/test_files/cpp/sources /tmp/cpp-bins
+
+# Sanity-check that rustc is able to build binaries, including ones that rely on
+# the runtime overflow check.
+COPY nix/docker/test_files/rust/ /tmp/test_files/rust/
+RUN /tmp/test_files/rust/compile-sources.sh /tmp/test_files/rust/sources /tmp/rust-bins
 
 # Tester: start from a clean BASE_IMAGE, install sanitizer runtime libraries,
 # and run the compiled test binaries to verify they execute correctly.
@@ -94,15 +98,18 @@ SHELL ["/bin/bash", "-e", "-o", "pipefail", "-c"]
 
 # Sanity-check that the built binaries run correctly in the vanilla base image, with the necessary sanitizer runtime libraries installed.
 COPY bin/install-sanitizer-libs.sh /tmp/install-sanitizer-libs.sh
-COPY nix/docker/test_files/run-test-binaries.sh /tmp/run-test-binaries.sh
-COPY --from=final /tmp/bins /tmp/bins
+COPY nix/docker/test_files/cpp/run-binaries.sh /tmp/test_files/cpp/run-binaries.sh
+COPY nix/docker/test_files/rust/run-binaries.sh /tmp/test_files/rust/run-binaries.sh
+COPY --from=final /tmp/cpp-bins /tmp/cpp-bins
+COPY --from=final /tmp/rust-bins /tmp/rust-bins
 
 RUN <<EOF
 if echo "${BASE_IMAGE}" | grep -qiE 'nixos'; then
     echo "Skipping runnning binaries on NixOS."
 else
     /tmp/install-sanitizer-libs.sh
-    /tmp/run-test-binaries.sh /tmp/bins
+    /tmp/test_files/cpp/run-binaries.sh /tmp/cpp-bins
+    /tmp/test_files/rust/run-binaries.sh /tmp/rust-bins
 fi
 touch /tmp/tests-passed
 EOF

nix/docker/README.md

@@ -42,9 +42,12 @@ work without `ca-certificates` being installed in the base image.
    - installs the dynamic linker if the base image lacks one (see
      [How libc is handled](#how-libc-is-handled)),
    - runs [`bin/check-tools.sh`](../../bin/check-tools.sh) to verify every
-     expected tool is present and runnable, and
+     expected tool is present and runnable.
    - compiles the C++ test programs in
-     [`test_files/`](./test_files) with both `g++` and `clang++`, and sanitizers.
+     [`test_files/cpp/sources/`](./test_files/cpp/sources) with both `g++` and
+     `clang++`, and sanitizers, and
+   - compiles the Rust test programs in
+     [`test_files/rust/sources/`](./test_files/rust/sources) with `rustc`.
 3. **`tester`** — Start again from a clean `BASE_IMAGE` (no Nix toolchain),
    install only the sanitizer runtime libraries
    ([`install-sanitizer-libs.sh`](./install-sanitizer-libs.sh)), and run the
@@ -73,11 +76,12 @@ toolchain being present at runtime. Two pieces make that work:
   [`loader-path.sh`](./loader-path.sh) reports the expected loader path for the
   current architecture, so we can patch the binaries to use the correct loader.
 
-The build then verifies all of this end to end: the test programs in
-`test_files/` (a regular binary plus ASan/TSan/UBSan variants) are compiled in
-`final`, their `PT_INTERP` is patched to the target loader, and they are run in
-the clean `tester` stage to confirm each emits the expected sanitizer
-diagnostic on a stock base image.
+The build then verifies all of this end to end: the C++ test programs in
+`test_files/cpp/sources/` (a regular binary plus ASan/TSan/UBSan variants) and
+the Rust test programs in `test_files/rust/sources/` (a hello binary plus panic
+and overflow-check variants) are compiled in `final`, their `PT_INTERP` is
+patched to the target loader, and they are run in the clean `tester` stage to
+confirm each emits the expected diagnostic on a stock base image.
 
 ## Files
 
@@ -85,6 +89,7 @@ diagnostic on a stock base image.
 | ----------------------------------------------------------------------- | ----------------------------------------------------------------------------- |
 | [`./Dockerfile`](./Dockerfile)                                          | Multi-stage build described above.                                            |
 | [`./loader-path.sh`](./loader-path.sh)                                  | Print the dynamic-linker (`PT_INTERP`) path for the current architecture.     |
-| [`./test_files/`](./test_files)                                         | C++ sources and scripts to compile and run the sanitizer smoke tests.         |
+| [`./test_files/cpp/`](./test_files/cpp)                                 | C++ sanitizer smoke test: sources + compile/run scripts.                      |
+| [`./test_files/rust/`](./test_files/rust)                               | Rust rustc smoke test: sources + compile/run scripts.                         |
 | [`/bin/check-tools.sh`](../../bin/check-tools.sh)                       | Verify every expected tools are present and runnable.                         |
 | [`/bin/install-sanitizer-libs.sh`](../../bin/install-sanitizer-libs.sh) | Install `libasan`/`libtsan`/`libubsan` runtimes on the supported base images. |

nix/docker/test_files/rust/compile-sources.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+# Compile all Rust test binaries during the Docker image build.
+# Each binary has the target system's ELF PT_INTERP (dynamic-linker path)
+# baked in so it can run on the (potentially minimal) final BASE_IMAGE.
+
+set -eo pipefail
+
+src_dir="${1:?usage: $0 <src_dir> <dst_dir>}"
+dst_dir="${2:?usage: $0 <src_dir> <dst_dir>}"
+
+loader="$(/tmp/loader-path.sh)"
+
+mkdir -p "${dst_dir}"
+
+function compile() {
+    local name="${1}"
+    local extra_flags="${2:-}"
+
+    local src="${src_dir}/${name}.rs"
+    local binary="${dst_dir}/${name}"
+
+    echo "=== Compiling ${name} with rustc ==="
+    # -O optimizes (opt-level 2); Rust statically links its own std, so the
+    # only dynamic dependency left is the system glibc (+ libgcc_s), exactly
+    # like the C++ binaries.
+    local compile_cmd="rustc --edition 2021 -O -g ${extra_flags} \
+        ${src} -o ${binary}"
+    echo "Compile cmd: ${compile_cmd}"
+    eval "${compile_cmd}"
+
+    echo "=== Patching ${binary} to use ${loader} as PT_INTERP ==="
+    local patch_cmd="patchelf --set-interpreter ${loader} --remove-rpath ${binary}"
+    echo "Patch cmd: ${patch_cmd}"
+    eval "${patch_cmd}"
+}
+
+# `-O` disables overflow checks by default, so `overflow` re-enables them
+# explicitly to exercise the runtime overflow check.
+compile hello
+compile panic
+compile overflow "-C overflow-checks=on"
+
+echo "=== All binaries compiled ==="
+
+ls -la "${dst_dir}"

nix/docker/test_files/rust/run-binaries.sh

@@ -0,0 +1,74 @@
+#!/bin/bash
+# Run pre-compiled Rust binaries and confirm each emits its expected diagnostic.
+# Binaries must already exist in <bins_dir> as <name> for name in
+# {hello,panic,overflow}.
+
+set -eo pipefail
+
+bins_dir="${1:?usage: $0 <bins_dir>}"
+
+failed_binaries=()
+
+# Run a binary and verify its exit code and output.
+# Usage: run <binary> <expected_output> <expected_rc>
+function run() {
+    local binary="${1}"
+    local expected_output="${2}"
+    local expected_rc="${3}"
+
+    local out_file
+    out_file="$(mktemp)"
+
+    echo "=== Run ${binary} ==="
+    set +e
+    "${binary}" >"${out_file}" 2>&1
+    local rc=$?
+    set -e
+
+    cat "${out_file}"
+
+    local failed=0
+    if [ "${expected_rc}" = "nonzero" ]; then
+        if [ "${rc}" -eq 0 ]; then
+            echo "ERROR: expected non-zero exit code from ${binary}, got ${rc}" >&2
+            failed=1
+        fi
+    elif [ "${rc}" -ne "${expected_rc}" ]; then
+        echo "ERROR: expected exit code ${expected_rc} from ${binary}, got ${rc}" >&2
+        failed=1
+    fi
+
+    if ! grep -q "${expected_output}" "${out_file}"; then
+        echo "ERROR: expected '${expected_output}' from ${binary}" >&2
+        failed=1
+    fi
+
+    if [ "${failed}" -eq 0 ]; then
+        echo "OK: '${expected_output}' detected"
+    else
+        failed_binaries+=("${binary}")
+    fi
+}
+
+declare -A expect=(
+    [hello]="Hello from main thread"
+    [panic]="explicit panic from test"
+    [overflow]="attempt to add with overflow"
+)
+
+for name in hello panic overflow; do
+    binary="${bins_dir}/${name}"
+
+    if [ "${name}" = "hello" ]; then
+        expected_rc=0
+    else
+        expected_rc=nonzero
+    fi
+    run "${binary}" "${expect[$name]}" "${expected_rc}"
+done
+
+if [ "${#failed_binaries[@]}" -gt 0 ]; then
+    echo "ERROR: the following binaries failed:" >&2
+    printf '  %s\n' "${failed_binaries[@]}" >&2
+    exit 1
+fi

nix/docker/test_files/rust/sources/hello.rs

@@ -0,0 +1,16 @@
+use std::thread;
+
+fn main() {
+    const NUM_THREADS: usize = 10;
+    let mut handles = Vec::with_capacity(NUM_THREADS);
+    for id in 0..NUM_THREADS {
+        handles.push(thread::spawn(move || {
+            println!("Hello from thread {id}");
+        }));
+    }
+    for handle in handles {
+        handle.join().expect("worker thread panicked");
+    }
+
+    println!("Hello from main thread");
+}

nix/docker/test_files/rust/sources/overflow.rs

@@ -0,0 +1,13 @@
+use std::hint::black_box;
+
+// Rust analogue of the C++ UBSan check: with overflow checks enabled the
+// compiler inserts a runtime check that panics on signed integer overflow.
+// `black_box` keeps the operands opaque so the addition is evaluated at
+// runtime rather than being rejected by the compile-time overflow lint.
+fn main() {
+    let max = black_box(i32::MAX);
+    let one = black_box(1);
+    println!("Current max: {max}");
+    let overflowed = max + one;
+    println!("Overflowed result: {overflowed}");
+}

nix/docker/test_files/rust/sources/panic.rs

@@ -0,0 +1,5 @@
+fn main() {
+    // Verify the panic runtime works: a panic must print its message to stderr
+    // and exit with a non-zero status (Rust's default panic exit code is 101).
+    panic!("explicit panic from test");
+}

nix/packages.nix

@@ -62,5 +62,15 @@ in
     runClangTidy
     vim
     zip
+    # Rust packages
+    cargo
+    cargo-audit
+    cargo-llvm-cov
+    cargo-nextest
+    clippy
+    corrosion
+    rust-analyzer
+    rustc
+    rustfmt
   ];
 }