Add wasi and emscripten to cmake presets as well as minimalist cmake toolchains

.github/workflows/cmake.yml

@@ -31,7 +31,7 @@ jobs:
 
       - name: Setup MacOS
         if: startsWith(matrix.os, 'macOS')
-        run: brew install automake autoconf ninja cmake
+        run: brew upgrade && brew install automake autoconf ninja cmake emscripten wasi-libc wasi-runtimes llvm
 
       - name: Setup Ubuntu
         if: startsWith(matrix.os, 'ubuntu')
@@ -41,15 +41,33 @@ jobs:
         uses: lukka/run-cmake@v10
         id: runcmake-ninja
         with:
-          configurePreset: 'ninja'
-          buildPreset: 'ninja-release'
-          testPreset: 'ninja-release'
+          configurePreset: "ninja"
+          buildPreset: "ninja-release"
+          testPreset: "ninja-release"
 
       - name: Run CMake+MSVC+CTest to generate/build/test.
         uses: lukka/run-cmake@v10
         if: startsWith(matrix.os, 'win')
         id: runcmake-msvc
         with:
-          configurePreset: 'msvc'
-          buildPreset: 'msvc-release'
-          testPreset: 'msvc-release'
+          configurePreset: "msvc"
+          buildPreset: "msvc-release"
+          testPreset: "msvc-release"
+
+      - name: Build emscripten plugin template.
+        uses: lukka/run-cmake@v10
+        if: startsWith(matrix.os, 'macOS')
+        id: runcmake-emscripten
+        with:
+          configurePreset: "emscripten"
+          buildPreset: "emscripten-release"
+
+      # TODO: enable it, unfortunately it currently fails (only on github, not my on OS) with:
+      #   clang: error: unable to execute command: posix_spawn failed: No such file or directory
+      # - name: Build wasi plugin template.
+      #   uses: lukka/run-cmake@v10
+      #   if: startsWith(matrix.os, 'macOS')
+      #   id: runcmake-wasi
+      #   with:
+      #     configurePreset: "wasi"
+      #     buildPreset: "wasi-release"

CMakeLists.txt

@@ -78,16 +78,22 @@ if (${CLAP_BUILD_TESTS})
     clap_compile_cpp(cpp11 cc 11 11)
     clap_compile_cpp(cpp14 cc 11 14)
     if(${CMAKE_VERSION} VERSION_LESS "3.21")
-       message(STATUS "Skipping C17 tests due to older CMAKE_VERSION ${CMAKE_VERSION}")
+        message(STATUS "Skipping C17 tests due to older CMAKE_VERSION ${CMAKE_VERSION}")
     else()
-      clap_compile_cpp(c17    c 17 17)
+        clap_compile_cpp(c17    c 17 17)
     endif()
     clap_compile_cpp(cpp17 cc 17 17)
     clap_compile_cpp(cpp20 cc 17 20)
 
     check_include_file(threads.h CLAP_HAS_THREADS_H)
 
-    add_library(clap-plugin-template MODULE EXCLUDE_FROM_ALL src/plugin-template.c)
+    if(CMAKE_SYSTEM_NAME STREQUAL "WASI")
+        set(CLAP_LIBRARY_TYPE STATIC)
+    else()
+        set(CLAP_LIBRARY_TYPE MODULE)
+    endif()
+
+    add_library(clap-plugin-template ${CLAP_LIBRARY_TYPE} EXCLUDE_FROM_ALL src/plugin-template.c)
     target_link_libraries(clap-plugin-template PRIVATE clap)
     set_target_properties(clap-plugin-template PROPERTIES C_STANDARD 11)
     add_dependencies(clap-tests clap-plugin-template)
@@ -114,5 +120,8 @@ if (${CLAP_BUILD_TESTS})
                     )
     elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows")
         set_target_properties(clap-plugin-template PROPERTIES SUFFIX ".clap" PREFIX "")
+    elseif(CMAKE_SYSTEM_NAME STREQUAL "WASI" OR CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+        target_link_options(clap-plugin-template PRIVATE --no-entry)
     endif()
+
 endif()

CMakePresets.json

@@ -39,6 +39,42 @@
           "value": true
         }
       }
+    },
+    {
+      "name": "wasi",
+      "displayName": "Ninja Clang WASM32/WASI",
+      "description": "Configure and generate Ninja project files for all configurations, using clang and targetting wasm32 and wasi",
+      "binaryDir": "${sourceDir}/builds/${presetName}",
+      "generator": "Ninja Multi-Config",
+      "cacheVariables": {
+        "CMAKE_EXPORT_COMPILE_COMMANDS": {
+          "type": "boolean",
+          "value": true
+        },
+        "CLAP_BUILD_TESTS": {
+          "type": "boolean",
+          "value": true
+        },
+        "CMAKE_TOOLCHAIN_FILE": "${sourceDir}/cmake/toolchains/clang-wasm32-wasi.cmake"
+      }
+    },
+    {
+      "name": "emscripten",
+      "displayName": "emscripten",
+      "description": "Configure and generate Ninja project files for all configurations, using emscripten",
+      "binaryDir": "${sourceDir}/builds/${presetName}",
+      "generator": "Ninja Multi-Config",
+      "cacheVariables": {
+        "CMAKE_EXPORT_COMPILE_COMMANDS": {
+          "type": "boolean",
+          "value": true
+        },
+        "CLAP_BUILD_TESTS": {
+          "type": "boolean",
+          "value": true
+        },
+        "CMAKE_TOOLCHAIN_FILE": "${sourceDir}/cmake/toolchains/emscripten.cmake"
+      }
     }
   ],
   "buildPresets": [
@@ -48,15 +84,31 @@
       "displayName": "Build ninja-release",
       "description": "Build ninja Release configuration",
       "configuration": "RelWithDebInfo",
-      "targets": ["clap-tests"]
+      "targets": ["clap-tests", "clap-plugin-template"]
     },
     {
       "name": "msvc-release",
       "configurePreset": "msvc",
       "displayName": "Build msvc-release",
       "description": "Build msvc Release configuration",
       "configuration": "RelWithDebInfo",
-      "targets": ["clap-tests"]
+      "targets": ["clap-tests", "clap-plugin-template"]
+    },
+    {
+      "name": "wasi-release",
+      "configurePreset": "wasi",
+      "displayName": "Build wasi-release",
+      "description": "Build wasi Release configuration",
+      "configuration": "RelWithDebInfo",
+      "targets": ["clap-tests", "clap-plugin-template"]
+    },
+    {
+      "name": "emscripten-release",
+      "configurePreset": "emscripten",
+      "displayName": "Build emscripten-release",
+      "description": "Build emscripten Release configuration",
+      "configuration": "RelWithDebInfo",
+      "targets": ["clap-tests", "clap-plugin-template"]
     }
   ],
   "testPresets": [
@@ -71,4 +123,4 @@
       "configuration": "RelWithDebInfo"
     }
   ]
-}
+}

cmake/toolchains/clang-wasm32-wasi.cmake

@@ -0,0 +1,31 @@
+# Simple toolchain example that targets wasm32 using wasi
+# On archlinux:
+#   pacman -S clang wasi-compiler-rt wasi-libc wasi-libc++ wasi-libc++abi
+# On macOS:
+#   homebrew install wasi-libc wasi-runtimes llvm
+#
+# For other OSes, make a copy of this file and do the necessary adjustments.
+
+set(CMAKE_SYSTEM_NAME "WASI")
+set(CMAKE_CROSSCOMPILING TRUE)
+
+set(CMAKE_C_COMPILER "clang")
+set(CMAKE_CXX_COMPILER "clang++")
+
+if(CMAKE_HOST_SYSTEM_NAME STREQUAL Linux)
+    set(CMAKE_SYSROOT "/usr/share/wasi-sysroot")
+elseif(CMAKE_HOST_SYSTEM_NAME STREQUAL Darwin)
+    set(CMAKE_SYSROOT "/opt/homebrew/share/wasi-sysroot")
+    set(CMAKE_C_COMPILER "/opt/homebrew/opt/llvm/bin/clang")
+    set(CMAKE_CXX_COMPILER "/opt/homebrew/opt/llvm/bin/clang++")
+    set(CMAKE_RANLIB "/opt/homebrew/opt/llvm/bin/llvm-ranlib")
+endif()
+
+# -nostdlib
+set(CMAKE_C_FLAGS_INIT "--target=wasm32-wasi")
+set(CMAKE_CXX_FLAGS_INIT "--target=wasm32-wasi")
+set(CMAKE_EXE_LINKER_FLAGS_INIT "-Wl,--export-all -Wl,--no-entry -lpthread")
+set(CMAKE_MODULE_LINKER_FLAGS_INIT "-Wl,--export-all -Wl,--no-entry -lpthread")
+set(CMAKE_SHARED_LINKER_FLAGS_INIT "-Wl,--export-all -Wl,--no-entry -lpthread")
+
+set(CMAKE_POSITION_INDEPENDENT_CODE TRUE)

cmake/toolchains/emscripten.cmake

@@ -0,0 +1,21 @@
+# Simple toolchain example that targets wasm32 using emscripten
+# On archlinux:
+#   pacman -S clang emscripten
+# On macOS:
+#   brew install emscripten
+#
+# For other OSes, make a copy of this file and do the necessary adjustments.
+
+set(CMAKE_SYSTEM_NAME "Emscripten")
+set(CMAKE_CROSSCOMPILING TRUE)
+
+if(CMAKE_HOST_SYSTEM_NAME STREQUAL Linux)
+    set(CMAKE_C_COMPILER "/usr/lib/emscripten/emcc")
+    set(CMAKE_CXX_COMPILER "/usr/lib/emscripten/em++")
+elseif(CMAKE_HOST_SYSTEM_NAME STREQUAL Darwin)
+    set(CMAKE_C_COMPILER "/opt/homebrew/bin/emcc")
+    set(CMAKE_CXX_COMPILER "/opt/homebrew/bin/em++")
+else()
+    set(CMAKE_C_COMPILER "emcc")
+    set(CMAKE_CXX_COMPILER "em++")
+endif()

src/plugin-template.c

@@ -8,7 +8,7 @@
 #include <stdio.h>
 #include <assert.h>
 
-#if __STDC_VERSION__ >= 201112L && !defined (__STDC_NO_THREADS__) && defined (CLAP_HAS_THREADS_H)
+#if __STDC_VERSION__ >= 201112L && !defined (__STDC_NO_THREADS__) && defined (CLAP_HAS_THREADS_H) && !defined (__wasi__)
 #   define CLAP_HAS_THREAD
 #   include <threads.h>
 #endif