cymon-lib 0.2: C++20, interrupt-safe API, DSDL 0.1, UNIMOC-ready

.clang-format

@@ -1,3 +1,21 @@
----
+# Use the Google style in this project.
 BasedOnStyle: Google
-ColumnLimit: 140
+
+# Some folks prefer to write "int& foo" while others prefer "int &foo".  The
+# Google Style Guide only asks for consistency within a project, we chose
+# "int& foo" for this project:
+DerivePointerAlignment: false
+PointerAlignment: Left
+
+# The Google Style Guide only asks for consistency w.r.t. "east const" vs.
+# "const west" alignment of cv-qualifiers. In this project we use "const west".
+QualifierAlignment: Left
+
+IncludeBlocks: Merge
+
+CommentPragmas: '(@copydoc|@copybrief|@see|@overload|@snippet)'
+
+ColumnLimit: 110
+BinPackArguments: false
+BinPackParameters: false
+PenaltyBreakBeforeFirstCallParameter: 1000

.clang-tidy

@@ -1,29 +1,57 @@
----
+# SPDX-License-Identifier: Apache-2.0
 Checks: >
-  bugprone-*,
-  -bugprone-easily-swappable-parameters,
-  -bugprone-exception-escape,
-  google-build-explicit-make-pairs,
-  google-build-namespaces,
-  google-build-using-namespace,
-  google-explicit-constructor,
-  google-global-names-in-headers,
-  google-readability-braces-around-statements,
-  google-readability-casting,
-  google-readability-namespace-comments,
-  -google-readability-todo,
-  google-runtime-int,
-  google-runtime-operator,
-  modernize-use-nullptr,
-  modernize-use-override,
-  modernize-use-emplace,
-  performance-for-range-copy,
-  performance-unnecessary-copy-initialization,
-  readability-braces-around-statements,
-  readability-const-return-type,
-  readability-container-size-empty,
-  readability-delete-null-pointer,
-  readability-else-after-return
+  clang-diagnostic-*,
+  clang-analyzer-*,
+  cppcoreguidelines-*,
+  modernize-*,
+  performance-*,
+  readability-*,
+  -modernize-use-trailing-return-type,
+  -readability-magic-numbers,
+  -cppcoreguidelines-avoid-magic-numbers,
+  -cppcoreguidelines-pro-bounds-pointer-arithmetic,
+  -cppcoreguidelines-pro-type-reinterpret-cast,
+  -cppcoreguidelines-pro-type-union-access,
+  -cppcoreguidelines-pro-bounds-constant-array-index
 
-WarningsAsErrors: ''
-HeaderFilterRegex: 'include/cymon/.*'
+# Indices into fixed-size arrays are loop counters bounded by the array size
+# constant. The suggested replacement (gsl::at or .at()) adds an abort path to
+# the zero-latency hot path, so the check is off.
+
+# The checks and naming rules of UNIMOC, so the library is clean when UNIMOC
+# builds it. The public headers are checked with the sources.
+HeaderFilterRegex: '.*/include/cymon/[^/]+\.hpp$'
+
+WarningsAsErrors: ""
+
+CheckOptions:
+  # Phase (a, b, c), axis (d, q), per-phase names (ia, da, ...) and the time
+  # step (dt) are the vocabulary of the motor-control code.
+  - key: readability-identifier-length.IgnoredVariableNames
+    value: "^(a|b|c|d|q|dt|ia|ib|ic|da|db|dc)$"
+  - key: readability-identifier-length.IgnoredParameterNames
+    value: "^(a|b|c|d|q|dt|ia|ib|ic|da|db|dc)$"
+  # Zephyr macros (LOG_*, K_USEC, zassert) would dominate the count.
+  - key: readability-function-cognitive-complexity.IgnoreMacros
+    value: true
+  - key: readability-identifier-naming.ClassCase
+    value: CamelCase
+  - key: readability-identifier-naming.FunctionCase
+    value: CamelCase
+  - key: readability-identifier-naming.VariableCase
+    value: lower_case
+  - key: readability-identifier-naming.ConstantCase
+    value: CamelCase
+  - key: readability-identifier-naming.ConstantPrefix
+    value: "k"
+  - key: readability-identifier-naming.MemberCase
+    value: lower_case
+  - key: readability-identifier-naming.MemberSuffix
+    value: "_"
+  - key: readability-identifier-naming.PublicMemberSuffix
+    value: ""
+  # Parameters are variables (snake_case), also when they are const.
+  - key: readability-identifier-naming.ParameterCase
+    value: lower_case
+  - key: readability-identifier-naming.ConstantParameterCase
+    value: lower_case

.github/workflows/ci.yml

@@ -1,45 +1,48 @@
 name: CI
 on:
-  push:
-    branches: [main, develop, "copilot/**"]
+  # Pull requests only; a push to a branch runs nothing.
   pull_request:
-    branches: [main, develop, "copilot/**"]
+  workflow_dispatch:
 
 jobs:
   build-and-test:
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        compiler: [g++, clang++]
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@v4
 
-      - name: Install system dependencies
+      - name: Install dependencies
         run: |
           sudo apt-get update -q
-          sudo apt-get install -y \
-            ninja-build clang clang-format clang-tidy
-
-      - name: Install CMake 4.x
-        run: pip install "cmake>=4,<5" --quiet
+          sudo apt-get install -y ninja-build clang clang-tidy
 
       - name: Configure
         run: |
-          cmake -S . -B build -G Ninja \
-            -DCMAKE_BUILD_TYPE=Debug \
-            -DCYMON_BUILD_TESTS=ON \
-            -DCMAKE_CXX_COMPILER=clang++ \
-            -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
+          cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Debug \
+            -DCMAKE_CXX_COMPILER=${{ matrix.compiler }} -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
 
-      - name: Build
+      - name: Build (warnings are errors)
         run: cmake --build build
 
       - name: Test
         run: ctest --test-dir build --output-on-failure
 
-      - name: clang-format check
-        run: |
-          find include src tests -name "*.hpp" -o -name "*.cpp" | \
-            xargs clang-format --dry-run --Werror
-
       - name: clang-tidy
-        run: |
-          find src -name "*.cpp" | \
-            xargs clang-tidy -p build/
+        if: matrix.compiler == 'clang++'
+        run: clang-tidy -p build --warnings-as-errors='*' src/cymon/*.cpp
+
+  format-and-dsdl:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+      - name: Install tools
+        run: pip install clang-format==22.1.1 "nunavut>=2.3,<3"
+      - name: clang-format
+        run: git ls-files '*.hpp' '*.cpp' | xargs clang-format --dry-run --Werror
+      - name: DSDL and generated C serialization
+        run: scripts/check_dsdl.sh

CMakeLists.txt

@@ -1,39 +1,46 @@
+# SPDX-License-Identifier: Apache-2.0
 # Copyright 2026 Tecnologic
 #
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
+# cymon-lib: device side of the cymon trace protocol (C++20, no heap, no
+# Cyphal dependency). Built standalone (host tests) or with add_subdirectory()
+# from a firmware build such as the UNIMOC Zephyr module, which then applies
+# its own toolchain flags; this file adds warnings only when it is the top
+# level project.
+
+cmake_minimum_required(VERSION 3.20)
+project(cymon-lib VERSION 0.2.0 LANGUAGES CXX)
 
-cmake_minimum_required(VERSION 3.20.0)
-project(cymon-lib VERSION 0.1.0 LANGUAGES CXX)
+set(CYMON_MAX_BUFFER_BYTES 4096 CACHE STRING "Capture buffer size in bytes")
+set(CYMON_MAX_VARS 64 CACHE STRING "Variables the registry holds (1..255)")
+set(CYMON_MAX_CHANNELS 8 CACHE STRING "Channels of one capture (1..16)")
 
-# Library
-add_library(cymon
+add_library(cymon STATIC
   src/cymon/trigger.cpp
   src/cymon/sample_buffer.cpp
   src/cymon/device.cpp
 )
-target_compile_features(cymon PUBLIC cxx_std_23)
-target_include_directories(cymon PUBLIC include)
-target_compile_options(cymon PRIVATE -Wall -Wextra -Wpedantic)
+add_library(cymon::cymon ALIAS cymon)
+target_compile_features(cymon PUBLIC cxx_std_20)
+target_include_directories(cymon PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/include)
+target_compile_definitions(cymon PUBLIC
+  CYMON_MAX_BUFFER_BYTES=${CYMON_MAX_BUFFER_BYTES}U
+  CYMON_MAX_VARS=${CYMON_MAX_VARS}U
+  CYMON_MAX_CHANNELS=${CYMON_MAX_CHANNELS}U
+)
+
+# Directory of the DSDL root namespace for the firmware's Nunavut generation.
+set(CYMON_DSDL_DIR ${CMAKE_CURRENT_SOURCE_DIR}/dsdl/cymon CACHE INTERNAL "cymon DSDL root namespace")
 
-# Optional nunavut DSDL code generation
-option(CYMON_GENERATE_DSDL "Generate C++ types from DSDL via nunavut" OFF)
-if(CYMON_GENERATE_DSDL)
-  include(cmake/nunavut.cmake)
-  generate_cyphal_types(cymon ${CMAKE_CURRENT_SOURCE_DIR}/dsdl)
+if(PROJECT_IS_TOP_LEVEL)
+  set(CMAKE_CXX_EXTENSIONS OFF)
+  # The warning set of UNIMOC, so the library builds clean inside it.
+  target_compile_options(cymon PRIVATE
+    -Wall -Wextra -Wpedantic -Wshadow -Wnon-virtual-dtor -Wold-style-cast -Wcast-align -Wunused
+    -Woverloaded-virtual -Wconversion -Wsign-conversion -Wnull-dereference -Wdouble-promotion
+    -Wformat=2 -Werror)
 endif()
 
-# Tests
-option(CYMON_BUILD_TESTS "Build tests" OFF)
+option(CYMON_BUILD_TESTS "Build the GoogleTest host tests" ${PROJECT_IS_TOP_LEVEL})
 if(CYMON_BUILD_TESTS)
   enable_testing()
   add_subdirectory(tests)