Squashed 'src/ipc/libmultiprocess/' changes from 27c7e8e5a5..c090cc8619

c090cc8619 build: require CapnProto 1.0.1 or better
b4120d34ba Merge bitcoin-core/libmultiprocess#192: doc: fix typos
6ecbdcd35a doc: fix typos
a11e6905c2 Merge bitcoin-core/libmultiprocess#186: Fix mptest failures in bitcoin CI
6f340a583f doc: fix DrahtBot LLM Linter error
c6f7fdf173 type-context: revert client disconnect workaround
e09143d2ea proxy-types: fix UndefinedBehaviorSanitizer: null-pointer-use
84b292fcc4 mptest: fix MemorySanitizer: use-of-uninitialized-value
fe4a188803 proxy-io: fix race conditions in disconnect callback code
d8011c8360 proxy-io: fix race conditions in ProxyClientBase cleanup handler
97e82ce19c doc: Add note about Waiter::m_mutex and interaction with the EventLoop::m_mutex
81d58f5580 refactor: Rename ProxyClient cleanup_it variable
07230f259f refactor: rename ProxyClient<Thread>::m_cleanup_it
c0efaa5e8c Merge bitcoin-core/libmultiprocess#187: ci: have bash scripts explicitly opt out of locale dependence.
0d986ff144 mptest: fix race condition in TestSetup constructor
d2f6aa2e84 ci: add thread sanitizer job
3a6db38e56 ci: rename configs to .bash
401e0ce1d9 ci: add copyright to bash scripts
e956467ae4 ci: export LC_ALL
8954cc0377 Merge bitcoin-core/libmultiprocess#184: Add CI jobs and fix clang-tidy and iwyu errors
757e13a755 ci: add gnu32 cross-compiled 32-bit build
15bf349000 doc: fix typo found by DrahtBot
1a598d5905 clang-tidy: drop 'bitcoin-*' check
cbb1e43fdc ci: test libc++ instead of libstdc++ in one job
76313450c2 type-context: disable clang-tidy UndefinedBinaryOperatorResult error
4896e7fe51 proxy-types: fix clang-tidy EnumCastOutOfRange error
060a739269 proxy-types: fix clang-tidy StackAddressEscape error
977d721020 ci: add github actions jobs testing gcc, clang-20, clang-tidy, and iwyu
0d5f1faae5 iwyu: fix add/remove include errors
753d2b10cc util: fix clang-tidy modernize-use-equals-default error
ae4f1dc2bb type-number: fix clang-tidy modernize-use-nullptr error
07a741bf69 proxy-types: fix clang-tidy bugprone-use-after-move error
3673114bc9 proxy-types: fix clang-tidy bugprone-use-after-move error
422923f384 proxy-types: fix clang-tidy bugprone-use-after-move error
c6784c6ade mpgen: disable clang-tidy misc-no-recursion error
c5498aa11b tidy: copy clang-tidy file from bitcoin core
258a617c1e Merge bitcoin-core/libmultiprocess#160: refactor: EventLoop locking cleanups + client disconnect exception
84cf56a0b5 test: Test disconnects during IPC calls
949573da84 Prevent IPC server crash if disconnected during IPC call
0198397580 Merge bitcoin-core/libmultiprocess#179: scripted-diff: Remove copyright year (ranges)
ea38392960 Prevent EventLoop async cleanup thread early exit during shutdown
616d9a75d2 doc: Document ProxyClientBase destroy_connection option
56fff76f94 Improve IPC client disconnected exceptions
9b8ed3dc5f refactor: Add clang thread safety annotations to EventLoop
52256e730f refactor: Remove DestructorCatcher and AsyncCallable
f24894794a refactor: Drop addClient/removeClient methods
2b830e558e refactor: Use EventLoopRef instead of addClient/removeClient
315ff537fb refactor: Add ProxyContext EventLoop* member
9aaeec3678 proxy-io.h: Add EventLoopRef RAII class handle addClient/removeClient refcounting
f58c8d8ba2 proxy-io.h: Add more detailed EventLoop comment
5108445e5d test: Add test coverage for client & server disconnections
59030c68cb Merge bitcoin-core/libmultiprocess#181: type-function.h: Fix CustomBuildField overload
688140b1df test: Add coverage for type-function.h
8b96229da5 type-function.h: Fix CustomBuildField overload
fa2ff9a668 scripted-diff: Remove copyright year (ranges)

git-subtree-dir: src/ipc/libmultiprocess
git-subtree-split: c090cc8619d6c003b86cbf63c1d43e64ff167d78

Author: Sjors

.clang-tidy

@@ -1,41 +1,40 @@
 Checks: '
 -*,
-bugprone-*,
--bugprone-easily-swappable-parameters,
--bugprone-exception-escape,
--bugprone-move-forwarding-reference,
--bugprone-narrowing-conversions,
--bugprone-reserved-identifier,
-misc-*,
--misc-non-private-member-variables-in-classes,
--misc-no-recursion,
--misc-unconventional-assign-operator,
--misc-unused-parameters,
--misc-use-anonymous-namespace,
-modernize-*,
--modernize-avoid-c-arrays,
--modernize-concat-nested-namespaces,
--modernize-deprecated-headers,
--modernize-use-nodiscard,
--modernize-use-trailing-return-type,
--modernize-use-using,
+bugprone-argument-comment,
+bugprone-move-forwarding-reference,
+bugprone-string-constructor,
+bugprone-use-after-move,
+bugprone-lambda-function-name,
+bugprone-unhandled-self-assignment,
+misc-unused-using-decls,
+misc-no-recursion,
+modernize-deprecated-headers,
+modernize-use-default-member-init,
+modernize-use-emplace,
+modernize-use-equals-default,
+modernize-use-noexcept,
+modernize-use-nullptr,
+modernize-use-starts-ends-with,
 performance-*,
 -performance-avoid-endl,
+-performance-enum-size,
+-performance-inefficient-string-concatenation,
+-performance-no-int-to-ptr,
 -performance-noexcept-move-constructor,
-readability-*,
--readability-braces-around-statements,
--readability-convert-member-functions-to-static,
--readability-else-after-return,
--readability-function-cognitive-complexity,
--readability-identifier-length,
--readability-implicit-bool-conversion,
--readability-inconsistent-declaration-parameter-name,
--readability-magic-numbers,
--readability-named-parameter,
--readability-uppercase-literal-suffix,
--readability-use-anyofallof,
+-performance-unnecessary-value-param,
+readability-const-return-type,
+readability-redundant-declaration,
+readability-redundant-string-init,
+clang-analyzer-core.*,
+-clang-analyzer-core.UndefinedBinaryOperatorResult,
+clang-analyzer-optin.core.*,
 '
+HeaderFilterRegex: '.'
+WarningsAsErrors: '*'
 CheckOptions:
- - key: modernize-use-override.IgnoreDestructors
-   value: true
-HeaderFilterRegex: 'example/calculator.h|example/init.h|example/printer.h|include/mp/proxy-io.h|include/mp/proxy-types.h|include/mp/proxy.h|include/mp/util.h|test/mp/test/foo-types.h|test/mp/test/foo.h'
+ - key: modernize-deprecated-headers.CheckHeaderFile
+   value: false
+ - key: performance-move-const-arg.CheckTriviallyCopyableMove
+   value: false
+ - key: bugprone-unhandled-self-assignment.WarnOnlyIfThisHasSuspiciousField
+   value: false

.github/workflows/ci.yml

@@ -0,0 +1,29 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        config: [default, llvm, gnu32, sanitize]
+
+    name: build • ${{ matrix.config }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Nix
+        uses: cachix/install-nix-action@v31       # 2025-05-27, from https://github.com/cachix/install-nix-action/tags
+        with:
+          nix_path: nixpkgs=channel:nixos-25.05   # latest release
+
+      - name: Run CI script
+        env:
+          CI_CONFIG: ci/configs/${{ matrix.config }}.bash
+        run: ci/scripts/run.sh

CMakeLists.txt

@@ -1,4 +1,4 @@
-# Copyright (c) 2019 The Bitcoin Core developers
+# Copyright (c) The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -12,19 +12,38 @@ endif()
 
 include("cmake/compat_find.cmake")
 
-find_package(CapnProto REQUIRED)
+find_package(CapnProto 1.0.1 REQUIRED)
 find_package(Threads REQUIRED)
 
-option(Libmultiprocess_ENABLE_CLANG_TIDY "Run clang-tidy with the compiler." OFF)
-if(Libmultiprocess_ENABLE_CLANG_TIDY)
+set(MPGEN_EXECUTABLE "" CACHE FILEPATH "If specified, should be full path to an external mpgen binary to use rather than the one built internally.")
+
+option(MP_ENABLE_CLANG_TIDY "Run clang-tidy with the compiler." OFF)
+if(MP_ENABLE_CLANG_TIDY)
   find_program(CLANG_TIDY_EXECUTABLE NAMES clang-tidy)
   if(NOT CLANG_TIDY_EXECUTABLE)
-    message(FATAL_ERROR "Libmultiprocess_ENABLE_CLANG_TIDY is ON but clang-tidy is not found.")
+    message(FATAL_ERROR "MP_ENABLE_CLANG_TIDY is ON but clang-tidy is not found.")
   endif()
   set(CMAKE_CXX_CLANG_TIDY "${CLANG_TIDY_EXECUTABLE}")
+
+  # Workaround for nix from https://gitlab.kitware.com/cmake/cmake/-/issues/20912#note_793338
+  # Nix injects header paths via $NIX_CFLAGS_COMPILE; CMake tags these as
+  # CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES and omits them from the compile
+  # database, so clang-tidy, which ignores $NIX_CFLAGS_COMPILE, can't find capnp
+  # headers. Setting them as standard passes them to clang-tidy.
+  set(CMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
 endif()
 
-set(MPGEN_EXECUTABLE "" CACHE FILEPATH "If specified, should be full path to an external mpgen binary to use rather than the one built internally.")
+option(MP_ENABLE_IWYU "Run include-what-you-use with the compiler." OFF)
+if(MP_ENABLE_IWYU)
+  find_program(IWYU_EXECUTABLE NAMES include-what-you-use iwyu)
+  if(NOT IWYU_EXECUTABLE)
+    message(FATAL_ERROR "MP_ENABLE_IWYU is ON but include-what-you-use was not found.")
+  endif()
+  set(CMAKE_CXX_INCLUDE_WHAT_YOU_USE "${IWYU_EXECUTABLE};-Xiwyu;--error")
+  if(DEFINED ENV{IWYU_MAPPING_FILE})
+    list(APPEND CMAKE_CXX_INCLUDE_WHAT_YOU_USE "-Xiwyu" "--mapping_file=$ENV{IWYU_MAPPING_FILE}")
+  endif()
+endif()
 
 include("cmake/compat_config.cmake")
 include("cmake/pthread_checks.cmake")
@@ -51,6 +70,7 @@ configure_file(include/mp/config.h.in "${CMAKE_CURRENT_BINARY_DIR}/include/mp/co
 
 # Generated C++ Capn'Proto schema files
 capnp_generate_cpp(MP_PROXY_SRCS MP_PROXY_HDRS include/mp/proxy.capnp)
+set_source_files_properties("${MP_PROXY_SRCS}" PROPERTIES SKIP_LINTING TRUE) # Ignored before cmake 3.27
 
 # util library
 add_library(mputil OBJECT src/mp/util.cpp)

ci/README.md

@@ -0,0 +1,25 @@
+### CI quick-reference
+
+All CI is just bash and nix.
+
+* **Workflow**:
+  -  `.github/workflows/ci.yml` – lists the jobs (`default`, `llvm`, …).
+* **Scripts**:
+  - `ci/scripts/run.sh` – spins up the Nix shell then calls…
+  - `ci/scripts/ci.sh` – …to configure, build, and test.
+* **Configuration**:
+  - `ci/configs/*.sh` – defines flags for each job.
+  - `shell.nix` – defines build environment (compilers, tools, libraries).
+* **Build directories**:
+  - `build-*/` – separate build directories (like `build-default`, `build-llvm`) will be created for each job.
+
+To run jobs locally:
+
+```bash
+CI_CONFIG=ci/configs/default.bash  ci/scripts/run.sh
+CI_CONFIG=ci/configs/llvm.bash     ci/scripts/run.sh
+CI_CONFIG=ci/configs/gnu32.bash    ci/scripts/run.sh
+CI_CONFIG=ci/configs/sanitize.bash ci/scripts/run.sh
+```
+
+By default CI jobs will reuse their build directories. `CI_CLEAN=1` can be specified to delete them before running instead.

ci/configs/default.bash

@@ -0,0 +1,5 @@
+CI_DESC="CI job using default libraries and tools, and running IWYU"
+CI_DIR=build-default
+export CXXFLAGS="-Werror -Wall -Wextra -Wpedantic -Wno-unused-parameter"
+CMAKE_ARGS=(-DMP_ENABLE_IWYU=ON)
+BUILD_ARGS=(-k)

ci/configs/gnu32.bash

@@ -0,0 +1,9 @@
+CI_DESC="CI job cross-compiling to 32-bit"
+CI_DIR=build-gnu32
+NIX_ARGS=(
+  --arg minimal true
+  --arg crossPkgs 'import <nixpkgs> { crossSystem = { config = "i686-unknown-linux-gnu"; }; }'
+)
+export CXXFLAGS="-Werror -Wall -Wextra -Wpedantic -Wno-unused-parameter"
+CMAKE_ARGS=(-G Ninja)
+BUILD_ARGS=(-k 0)

ci/configs/llvm.bash

@@ -0,0 +1,11 @@
+CI_DESC="CI job using LLVM-based libraries and tools (clang, libc++, clang-tidy, iwyu) and testing Ninja"
+CI_DIR=build-llvm
+NIX_ARGS=(--arg enableLibcxx true)
+export CXX=clang++
+export CXXFLAGS="-Werror -Wall -Wextra -Wpedantic -Wthread-safety-analysis -Wno-unused-parameter"
+CMAKE_ARGS=(
+  -G Ninja
+  -DMP_ENABLE_CLANG_TIDY=ON
+  -DMP_ENABLE_IWYU=ON
+)
+BUILD_ARGS=(-k 0)

ci/configs/sanitize.bash

@@ -0,0 +1,7 @@
+CI_DESC="CI job running ThreadSanitizer"
+CI_DIR=build-sanitize
+export CXX=clang++
+export CXXFLAGS="-ggdb -Werror -Wall -Wextra -Wpedantic -Wthread-safety-analysis -Wno-unused-parameter -fsanitize=thread"
+CMAKE_ARGS=()
+BUILD_ARGS=(-k -j4)
+BUILD_TARGETS=(mptest)

ci/scripts/ci.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+#
+# Copyright (c) The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+export LC_ALL=C.UTF-8
+
+set -o errexit -o nounset -o pipefail -o xtrace
+
+[ "${CI_CONFIG+x}" ] && source "$CI_CONFIG"
+
+: "${CI_DIR:=build}"
+if ! [ -v BUILD_TARGETS ]; then
+  BUILD_TARGETS=(all tests mpexamples)
+fi
+
+[ -n "${CI_CLEAN-}" ] && rm -rf "${CI_DIR}"
+
+cmake -B "$CI_DIR" "${CMAKE_ARGS[@]+"${CMAKE_ARGS[@]}"}"
+cmake --build "$CI_DIR" -t "${BUILD_TARGETS[@]}" -- "${BUILD_ARGS[@]+"${BUILD_ARGS[@]}"}"
+ctest --test-dir "$CI_DIR" --output-on-failure

ci/scripts/run.sh

@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+#
+# Copyright (c) The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+export LC_ALL=C.UTF-8
+
+set -o errexit -o nounset -o pipefail -o xtrace
+
+[ "${CI_CONFIG+x}" ] && source "$CI_CONFIG"
+
+nix-shell --pure --keep CI_CONFIG --keep CI_CLEAN "${NIX_ARGS[@]+"${NIX_ARGS[@]}"}" --run ci/scripts/ci.sh shell.nix