Rewrite CMake support

- Add back macOS and Linux support
- Remove Corrosion from tree since it's only an implementation detail
- Decouple the Windows example from the top-level CMake project
- Add ARM64 support (at least for Windows)

Author: DataTriny

.github/workflows/bindings.yml

@@ -84,7 +84,7 @@ jobs:
 
       - if: startsWith(matrix.os, 'windows')
         run: |
-          mv target/${{ matrix.target }}/release/accesskit.dll.lib artifacts/${{ matrix.path }}/shared/accesskit.lib
+          mv target/${{ matrix.target }}/release/accesskit.dll.lib artifacts/${{ matrix.path }}/static
           mv target/${{ matrix.target }}/release/*.pdb artifacts/${{ matrix.path }}/shared
       - if: contains(matrix.path, 'mingw')
         run: mv target/${{ matrix.target }}/release/libaccesskit.dll.a artifacts/${{ matrix.path }}/shared/libaccesskit.a
@@ -118,9 +118,8 @@ jobs:
           mkdir -p accesskit_c/lib
           mv artifacts/headers accesskit_c/include
           cp -r artifacts/*/* accesskit_c/lib
-          cp -r bindings/c/corrosion accesskit_c/
           cp -r bindings/c/examples accesskit_c/
-          cp bindings/c/CMakeLists.txt accesskit_c/
+          cp bindings/c/accesskit-config.cmake accesskit_c/
           cp bindings/c/*.md accesskit_c/
           cp LICENSE* accesskit_c/
           mv accesskit_c ${{ github.ref_name }}

bindings/c/.gitignore

@@ -1,2 +1,3 @@
 build
 include
+lib

bindings/c/CMakeLists.txt

@@ -2,45 +2,30 @@ cmake_minimum_required(VERSION 3.20)
 
 project(accesskit_c)
 
-SET(ACCESSKIT_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/include)
-SET(ACCESSKIT_IN_REPO ON)
-if (EXISTS(${CMAKE_SOURCE_DIR}/lib))
-    SET(ACCESSKIT_IN_REPO OFF)
-    if (WIN32)
-        if (MINGW)
-            if (CMAKE_SIZEOF_VOID_P MATCHES 8)
-                SET(ACCESSKIT_LIBRARY_DIR ${CMAKE_SOURCE_DIR}/lib/windows/x86_64/mingw/static)
-            else()
-                SET(ACCESSKIT_LIBRARY_DIR ${CMAKE_SOURCE_DIR}/lib/windows/x86/mingw/static)
-            endif()
-        else()
-            if (CMAKE_SIZEOF_VOID_P MATCHES 8)
-                SET(ACCESSKIT_LIBRARY_DIR ${CMAKE_SOURCE_DIR}/lib/windows/x86_64/msvc/static)
-            else()
-                SET(ACCESSKIT_LIBRARY_DIR ${CMAKE_SOURCE_DIR}/lib/windows/x86/msvc/static)
-            endif()
-        endif()
-    endif()
-else()
-    add_subdirectory(corrosion)
-    corrosion_import_crate(MANIFEST_PATH Cargo.toml)
+include(accesskit-config.cmake)
+include(FetchContent)
 
-    find_program(RUSTUP rustup)
-    find_program(CBINDGEN cbindgen)
-    find_program(CLANG_FORMAT clang-format)
+FetchContent_Declare(
+    Corrosion
+    GIT_REPOSITORY https://github.com/corrosion-rs/corrosion.git
+    GIT_TAG v0.3.5
+)
+FetchContent_MakeAvailable(Corrosion)
 
-    add_custom_target(headers
-        COMMAND ${RUSTUP} run nightly ${CBINDGEN} --crate accesskit_c --output "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${CMAKE_SOURCE_DIR}"
-        COMMAND ${CLANG_FORMAT} -i "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp"
-        COMMAND ${CMAKE_COMMAND} -E rename "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
-        BYPRODUCTS "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
-    )
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${ACCESSKIT_LIBRARIES_DIR}static")
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${ACCESSKIT_LIBRARIES_DIR}shared")
+set(CMAKE_PDB_OUTPUT_DIRECTORY "${ACCESSKIT_LIBRARIES_DIR}shared")
+corrosion_import_crate(MANIFEST_PATH Cargo.toml)
 
-    add_dependencies(cargo-prebuild_accesskit headers)
-endif()
+find_program(RUSTUP rustup)
+find_program(CBINDGEN cbindgen)
+find_program(CLANG_FORMAT clang-format)
 
-option(BUILD_WINDOWS_EXAMPLE "Build the Windows example" OFF)
+add_custom_target(headers
+    COMMAND ${RUSTUP} run nightly ${CBINDGEN} --crate accesskit_c --output "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${CMAKE_SOURCE_DIR}"
+    COMMAND ${CLANG_FORMAT} -i "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp"
+    COMMAND ${CMAKE_COMMAND} -E rename "${ACCESSKIT_INCLUDE_DIR}/accesskit.hpp" "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
+    BYPRODUCTS "${ACCESSKIT_INCLUDE_DIR}/accesskit.h"
+)
 
-if (BUILD_WINDOWS_EXAMPLE)
-    add_subdirectory(examples/windows)
-endif()
+add_dependencies(cargo-prebuild_accesskit headers)

bindings/c/README.md

@@ -2,24 +2,47 @@
 
 These are the bindings to use AccessKit from other languages through FFI such as in C.
 
-## Prerequisites
+## How to use in a CMake project
+
+Decompress an accesskit_c release and place the resulting folder somewhere:
+
+- already known by CMake,
+- listed in your `CMAKE_PREFIX_PATH`,
+- indicated by the `ACCESSKIT_DIR` option.
+
+You can then require AccessKit as a dependency by adding this to your `CMakeLists.txt`:
+
+```cmake
+find_package(ACCESSKIT REQUIRED)
+```
+
+The headers can be added like so:
+
+```cmake
+include_directories(YourProject ${ACCESSKIT_INCLUDE_DIR})
+```
+
+Finally, link the library to your executable:
+
+```cmake
+target_link_libraries(YourExecutable PUBLIC ${ACCESSKIT_LIBRARIES})
+```
+
+See [the `examples` directory](https://github.com/AccessKit/accesskit/tree/main/bindings/c/examples) for project integration examples.
+
+## Building from source
+
+Prerequisites:
 
 - [Rust](https://rustup.rs/)
 - [CMake](https://cmake.org/), version 3.20 or higher
 - A nightly Rust toolchain: `rustup install nightly`
 - [cbindgen](https://github.com/eqrion/cbindgen): `cargo install cbindgen`
 - [clang-format](https://releases.llvm.org/14.0.0/tools/clang/docs/ClangFormat.html), version 14 or higher
 
-## Building
-
-Once inside the `bindings/c` directory, CMake can be used like so:
+Once inside the `bindings/c` directory, CMake can be used like this to build the project:
 
 ```bash
-cmake -S . -B build -DCMAKE_BUILD_TYPE=Release # See below for available configuration options.
-cd build
-cmake --build .
+cmake -S . -B build -DCMAKE_BUILD_TYPE=Release
+cmake --build build
 ```
-
-Available configuration options:
-
-- `BUILD_WINDOWS_EXAMPLE`: Builds the Windows example program

bindings/c/accesskit-config.cmake

@@ -0,0 +1,34 @@
+set(ACCESSKIT_INCLUDE_DIR "${CMAKE_CURRENT_LIST_DIR}/include")
+if (APPLE)
+    set(_ACCESSKIT_OS "macos")
+elseif (UNIX)
+    set(_ACCESSKIT_OS "linux")
+elseif (WIN32)
+    set(_ACCESSKIT_OS "windows")
+    if (MINGW)
+        set(_ACCESSKIT_TOOLCHAIN "mingw/")
+    else()
+        set(_ACCESSKIT_TOOLCHAIN "msvc/")
+    endif()
+    if (CMAKE_VS_PLATFORM_NAME)
+        string(TOLOWER "${CMAKE_VS_PLATFORM_NAME}" LOWER_VS_PLATFORM_NAME)
+        if ("${LOWER_VS_PLATFORM_NAME}" STREQUAL "arm64")
+            set(_ACCESSKIT_ARCH "arm64")
+            set(_ACCESSKIT_TOOLCHAIN "")
+        endif()
+    endif()
+endif()
+if (NOT _ACCESSKIT_TOOLCHAIN)
+    set(_ACCESSKIT_TOOLCHAIN "")
+endif()
+if (NOT _ACCESSKIT_ARCH)
+    if (CMAKE_SYSTEM_PROCESSOR MATCHES "^(AMD64|amd64|x86_64)$")
+        set(_ACCESSKIT_ARCH "x86_64")
+    elseif (CMAKE_SYSTEM_PROCESSOR MATCHES "^(ARM64|arm64|aarch64)$")
+        set(_ACCESSKIT_ARCH "arm64")
+    elseif (CMAKE_SYSTEM_PROCESSOR MATCHES "^(X86|x86|i686)$")
+        set(_ACCESSKIT_ARCH "x86")
+    endif()
+endif()
+set(ACCESSKIT_LIBRARIES_DIR "${CMAKE_CURRENT_LIST_DIR}/lib/${_ACCESSKIT_OS}/${_ACCESSKIT_ARCH}/${_ACCESSKIT_TOOLCHAIN}")
+find_library(ACCESSKIT_LIBRARIES accesskit ${ACCESSKIT_LIBRARIES_DIR}/static)