feat: implement cymon-lib — DSDL protocol, C++ device API, gtest suite, CI pipeline

.clang-format

@@ -0,0 +1,3 @@
+---
+BasedOnStyle: Google
+ColumnLimit: 140

.clang-tidy

@@ -0,0 +1,29 @@
+---
+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
+
+WarningsAsErrors: ''
+HeaderFilterRegex: 'include/cymon/.*'

.github/workflows/ci.yml

@@ -0,0 +1,40 @@
+name: CI
+on:
+  push:
+    branches: [main, "copilot/**"]
+  pull_request:
+    branches: [main]
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install tools
+        run: |
+          sudo apt-get update && sudo apt-get install -y \
+            cmake ninja-build clang clang-format clang-tidy
+
+      - name: Configure
+        run: |
+          cmake -B build -G Ninja \
+            -DCMAKE_BUILD_TYPE=Debug \
+            -DCMAKE_CXX_COMPILER=clang++ \
+            -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
+
+      - name: Build
+        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/

.gitignore

@@ -67,3 +67,6 @@ vcpkg_installed/
 # test output & cache
 Testing/
 .cache/
+
+# nunavut generated headers
+generated/

CMakeLists.txt

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+# 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.
+
+cmake_minimum_required(VERSION 3.20)
+project(cymon-lib VERSION 0.1.0 LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
+# Library
+add_library(cymon
+  src/cymon/trigger.cpp
+  src/cymon/sample_buffer.cpp
+  src/cymon/device.cpp
+)
+target_include_directories(cymon PUBLIC include)
+target_compile_options(cymon PRIVATE -Wall -Wextra -Wpedantic)
+
+# 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)
+endif()
+
+# Tests
+option(CYMON_BUILD_TESTS "Build tests" ON)
+if(CYMON_BUILD_TESTS)
+  enable_testing()
+  add_subdirectory(tests)
+endif()

README.md

@@ -1 +1,85 @@
-# cymon-lib
+# cymon-lib
+
+[![CI](https://github.com/Tecnologic/cymon-lib/actions/workflows/ci.yml/badge.svg)](https://github.com/Tecnologic/cymon-lib/actions/workflows/ci.yml)
+
+Platform-agnostic C++17 library for Cyphal-connected embedded nodes.
+Exposes named scalar variables and oscilloscope-style capture via a Cyphal
+CAN-FD service protocol. The library is pure C++ with no Cyphal/canard
+dependency — the integrating application calls the library's handlers when
+it receives a Cyphal service request.
+
+## Features
+
+- **Named variable registry** — register up to `CYMON_MAX_VARS` (default 64)
+  scalar variables with a `std::function<float()>` getter and iterate them
+  via a `GetVariableList`-style index query.
+- **Oscilloscope-style capture** — configurable number of channels,
+  sample count, pre-trigger depth, and trigger modes (rising, falling,
+  hysteresis).
+- **Paged readout** — `ReadSamples` returns interleaved float frames in pages
+  so the caller can fit data into Cyphal transfer payloads.
+- **Hardware-agnostic timer interface** — call `Device::Tick()` from your
+  timer ISR/task; report the actual achieved period with
+  `set_actual_sample_period_us()`.
+- **Compile-time limits** — override `CYMON_MAX_BUFFER_BYTES` and
+  `CYMON_MAX_VARS` via preprocessor defines before including any header.
+
+## Protocol (DSDL)
+
+All DSDL types live under `dsdl/cymon/` and are **unregulated** (no numeric
+port-ID prefix).
+
+| Service / Message       | Description                                      |
+|-------------------------|--------------------------------------------------|
+| `GetVariableList.1.0`   | Iterator-style variable enumeration (index→name) |
+| `GetBufferInfo.1.0`     | Query buffer limits                              |
+| `SetupCapture.1.0`      | Configure channels, sample count, pretrigger     |
+| `ArmTrigger.1.0`        | Arm/disarm trigger with level & mode             |
+| `ReadSamples.1.0`       | Paged readout of captured samples                |
+| `TriggerEvent.1.0`      | Broadcast message emitted when trigger fires     |
+
+## Build
+
+```bash
+cmake -B build -DCMAKE_BUILD_TYPE=Debug
+cmake --build build
+ctest --test-dir build --output-on-failure
+```
+
+To build with a specific compiler:
+
+```bash
+cmake -B build -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_BUILD_TYPE=Debug
+cmake --build build
+```
+
+To disable tests:
+
+```bash
+cmake -B build -DCYMON_BUILD_TESTS=OFF
+cmake --build build
+```
+
+## Integration
+
+```cpp
+#include "cymon/device.hpp"
+
+cymon::Device device;
+
+// Register variables (call once at startup).
+device.RegisterVariable("speed", "rpm", [] { return read_speed(); });
+device.RegisterVariable("current", "A",  [] { return read_current(); });
+
+// In your Cyphal service handler:
+auto resp = device.HandleSetupCapture(config);
+auto resp = device.HandleArmTrigger(arm_cfg);
+auto resp = device.HandleReadSamples(frame_offset, max_frames);
+
+// In your hardware timer ISR / task:
+device.Tick();
+```
+
+## License
+
+Apache 2.0 — see [LICENSE](LICENSE).

cmake/nunavut.cmake

@@ -0,0 +1,53 @@
+# 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.
+
+# generate_cyphal_types(target dsdl_dir)
+# Generates C++ headers from DSDL files using nunavut and adds them to target.
+function(generate_cyphal_types target dsdl_dir)
+  find_program(NUNAVUT_EXECUTABLE nunavut
+    HINTS "$ENV{HOME}/.local/bin" "/usr/local/bin"
+    DOC "nunavut DSDL code generation tool"
+  )
+
+  if(NOT NUNAVUT_EXECUTABLE)
+    message(FATAL_ERROR
+      "nunavut not found. Install it with: pip install nunavut\n"
+      "Then re-run cmake."
+    )
+  endif()
+
+  set(generated_dir "${CMAKE_BINARY_DIR}/generated")
+  file(MAKE_DIRECTORY "${generated_dir}")
+
+  file(GLOB_RECURSE dsdl_files "${dsdl_dir}/*.dsdl")
+
+  add_custom_command(
+    OUTPUT "${generated_dir}/.nunavut_stamp"
+    COMMAND "${NUNAVUT_EXECUTABLE}"
+      --target-language c++
+      --outdir "${generated_dir}"
+      "${dsdl_dir}"
+    COMMAND "${CMAKE_COMMAND}" -E touch "${generated_dir}/.nunavut_stamp"
+    DEPENDS ${dsdl_files}
+    COMMENT "Generating Cyphal C++ types from DSDL"
+    VERBATIM
+  )
+
+  add_custom_target(nunavut_generate
+    DEPENDS "${generated_dir}/.nunavut_stamp"
+  )
+
+  add_dependencies(${target} nunavut_generate)
+  target_include_directories(${target} PUBLIC "${generated_dir}")
+endfunction()

dsdl/cymon/ArmTrigger.1.0.dsdl

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+# 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.
+
+bool arm
+uint8 source_variable_id
+cymon.TriggerMode.1.0 mode
+float32 level
+float32 hysteresis_band
+---
+bool ok
+uint8 error_code

dsdl/cymon/GetBufferInfo.1.0.dsdl

@@ -0,0 +1,20 @@
+# 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.
+
+# Empty request — returns capture buffer limits.
+
+---
+uint32 buffer_bytes
+uint8 max_channels
+uint16 max_frames  # total frames storable; divide by your channel count to get per-channel depth

dsdl/cymon/GetVariableList.1.0.dsdl

@@ -0,0 +1,22 @@
+# 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.
+
+# Iterator-style variable list request, similar to uavcan.register.List.
+# Request the variable at the given index; empty name signals end of list.
+
+uint16 index
+---
+uint8 id
+uint8[<=32] name  # UTF-8 variable name; empty = end of list sentinel
+uint8[<=8] unit   # engineering unit string, e.g. "rpm", "A", "V"

dsdl/cymon/ReadSamples.1.0.dsdl

@@ -0,0 +1,23 @@
+# 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.
+
+# Paged read-out of captured samples.
+
+uint16 frame_offset  # page index: 0 = first page, increment by max_frames to page through capture
+uint8 max_frames
+---
+bool triggered
+bool end_of_data
+uint8 num_channels
+float32[<=64] samples  # interleaved: num_channels floats per frame

dsdl/cymon/SetupCapture.1.0.dsdl

@@ -0,0 +1,22 @@
+# 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.
+
+uint8[<=16] channel_ids
+float32 sample_period_us
+uint16 num_samples
+uint16 pretrigger_samples
+---
+bool ok
+uint8 error_code
+float32 actual_sample_period_us   # period actually used by hardware, may differ from requested