preparing for cmkr...

cmkr.cmake

@@ -0,0 +1,162 @@
+include_guard()
+
+# Change these defaults to point to your infrastructure if desired
+set(CMKR_REPO "https://github.com/build-cpp/cmkr" CACHE STRING "cmkr git repository" FORCE)
+set(CMKR_TAG "archive_264e4ace" CACHE STRING "cmkr git tag (this needs to be available forever)" FORCE)
+
+# Set these from the command line to customize for development/debugging purposes
+set(CMKR_EXECUTABLE "" CACHE FILEPATH "cmkr executable")
+set(CMKR_SKIP_GENERATION OFF CACHE BOOL "skip automatic cmkr generation")
+
+# Disable cmkr if generation is disabled
+if(DEFINED ENV{CI} OR CMKR_SKIP_GENERATION)
+    message(STATUS "[cmkr] Skipping automatic cmkr generation")
+    macro(cmkr)
+    endmacro()
+    return()
+endif()
+
+# Disable cmkr if no cmake.toml file is found
+if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/cmake.toml")
+    message(AUTHOR_WARNING "[cmkr] Not found: ${CMAKE_CURRENT_SOURCE_DIR}/cmake.toml")
+    macro(cmkr)
+    endmacro()
+    return()
+endif()
+
+# Convert a Windows native path to CMake path
+if(CMKR_EXECUTABLE MATCHES "\\\\")
+    string(REPLACE "\\" "/" CMKR_EXECUTABLE_CMAKE "${CMKR_EXECUTABLE}")
+    set(CMKR_EXECUTABLE "${CMKR_EXECUTABLE_CMAKE}" CACHE FILEPATH "" FORCE)
+    unset(CMKR_EXECUTABLE_CMAKE)
+endif()
+
+# Helper macro to execute a process (COMMAND_ERROR_IS_FATAL ANY is 3.19 and higher)
+function(cmkr_exec)
+    execute_process(COMMAND ${ARGV} RESULT_VARIABLE CMKR_EXEC_RESULT)
+    if(NOT CMKR_EXEC_RESULT EQUAL 0)
+        message(FATAL_ERROR "cmkr_exec(${ARGV}) failed (exit code ${CMKR_EXEC_RESULT})")
+    endif()
+endfunction()
+
+# Windows-specific hack (CMAKE_EXECUTABLE_PREFIX is not set at the moment)
+if(WIN32)
+    set(CMKR_EXECUTABLE_NAME "cmkr.exe")
+else()
+    set(CMKR_EXECUTABLE_NAME "cmkr")
+endif()
+
+# Use cached cmkr if found
+set(CMKR_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/_cmkr_${CMKR_TAG}")
+set(CMKR_CACHED_EXECUTABLE "${CMKR_DIRECTORY}/bin/${CMKR_EXECUTABLE_NAME}")
+
+if(NOT CMKR_CACHED_EXECUTABLE STREQUAL CMKR_EXECUTABLE AND CMKR_EXECUTABLE MATCHES "^${CMAKE_CURRENT_BINARY_DIR}/_cmkr")
+    message(AUTHOR_WARNING "[cmkr] Upgrading '${CMKR_EXECUTABLE}' to '${CMKR_CACHED_EXECUTABLE}'")
+    unset(CMKR_EXECUTABLE CACHE)
+endif()
+
+if(CMKR_EXECUTABLE AND EXISTS "${CMKR_EXECUTABLE}")
+    message(VERBOSE "[cmkr] Found cmkr: '${CMKR_EXECUTABLE}'")
+elseif(CMKR_EXECUTABLE AND NOT CMKR_EXECUTABLE STREQUAL CMKR_CACHED_EXECUTABLE)
+    message(FATAL_ERROR "[cmkr] '${CMKR_EXECUTABLE}' not found")
+else()
+    set(CMKR_EXECUTABLE "${CMKR_CACHED_EXECUTABLE}" CACHE FILEPATH "Full path to cmkr executable" FORCE)
+    message(VERBOSE "[cmkr] Bootstrapping '${CMKR_EXECUTABLE}'")
+    
+    message(STATUS "[cmkr] Fetching cmkr...")
+    if(EXISTS "${CMKR_DIRECTORY}")
+        cmkr_exec("${CMAKE_COMMAND}" -E rm -rf "${CMKR_DIRECTORY}")
+    endif()
+    find_package(Git QUIET REQUIRED)
+    cmkr_exec("${GIT_EXECUTABLE}"
+        clone
+        --config advice.detachedHead=false
+        --branch ${CMKR_TAG}
+        --depth 1
+        ${CMKR_REPO}
+        "${CMKR_DIRECTORY}"
+    )
+    message(STATUS "[cmkr] Building cmkr...")
+    cmkr_exec("${CMAKE_COMMAND}"
+        --no-warn-unused-cli
+        "${CMKR_DIRECTORY}"
+        "-B${CMKR_DIRECTORY}/build"
+        "-DCMAKE_BUILD_TYPE=Release"
+        "-DCMAKE_INSTALL_PREFIX=${CMKR_DIRECTORY}"
+        "-DCMKR_GENERATE_DOCUMENTATION=OFF"
+    )
+    cmkr_exec("${CMAKE_COMMAND}"
+        --build "${CMKR_DIRECTORY}/build"
+        --config Release
+        --parallel
+    )
+    cmkr_exec("${CMAKE_COMMAND}"
+        --install "${CMKR_DIRECTORY}/build"
+        --config Release
+        --prefix "${CMKR_DIRECTORY}"
+        --component cmkr
+    )
+    if(NOT EXISTS ${CMKR_EXECUTABLE})
+        message(FATAL_ERROR "[cmkr] Failed to bootstrap '${CMKR_EXECUTABLE}'")
+    endif()
+    cmkr_exec("${CMKR_EXECUTABLE}" version)
+    message(STATUS "[cmkr] Bootstrapped ${CMKR_EXECUTABLE}")
+endif()
+execute_process(COMMAND "${CMKR_EXECUTABLE}" version
+    RESULT_VARIABLE CMKR_EXEC_RESULT
+)
+if(NOT CMKR_EXEC_RESULT EQUAL 0)
+    message(FATAL_ERROR "[cmkr] Failed to get version, try clearing the cache and rebuilding")
+endif()
+
+# This is the macro that contains black magic
+macro(cmkr)
+    # When this macro is called from the generated file, fake some internal CMake variables
+    get_source_file_property(CMKR_CURRENT_LIST_FILE "${CMAKE_CURRENT_LIST_FILE}" CMKR_CURRENT_LIST_FILE)
+    if(CMKR_CURRENT_LIST_FILE)
+        set(CMAKE_CURRENT_LIST_FILE "${CMKR_CURRENT_LIST_FILE}")
+        get_filename_component(CMAKE_CURRENT_LIST_DIR "${CMAKE_CURRENT_LIST_FILE}" DIRECTORY)
+    endif()
+
+    # File-based include guard (include_guard is not documented to work)
+    get_source_file_property(CMKR_INCLUDE_GUARD "${CMAKE_CURRENT_LIST_FILE}" CMKR_INCLUDE_GUARD)
+    if(NOT CMKR_INCLUDE_GUARD)
+        set_source_files_properties("${CMAKE_CURRENT_LIST_FILE}" PROPERTIES CMKR_INCLUDE_GUARD TRUE)
+
+        file(SHA256 "${CMAKE_CURRENT_LIST_FILE}" CMKR_LIST_FILE_SHA256_PRE)
+
+        # Generate CMakeLists.txt
+        cmkr_exec("${CMKR_EXECUTABLE}" gen
+            WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+        )
+
+        file(SHA256 "${CMAKE_CURRENT_LIST_FILE}" CMKR_LIST_FILE_SHA256_POST)
+
+        # Delete the temporary file if it was left for some reason
+        set(CMKR_TEMP_FILE "${CMAKE_CURRENT_SOURCE_DIR}/CMakerLists.txt")
+        if(EXISTS "${CMKR_TEMP_FILE}")
+            file(REMOVE "${CMKR_TEMP_FILE}")
+        endif()
+
+        if(NOT CMKR_LIST_FILE_SHA256_PRE STREQUAL CMKR_LIST_FILE_SHA256_POST)
+            # Copy the now-generated CMakeLists.txt to CMakerLists.txt
+            # This is done because you cannot include() a file you are currently in
+            configure_file(CMakeLists.txt "${CMKR_TEMP_FILE}" COPYONLY)
+            
+            # Add the macro required for the hack at the start of the cmkr macro
+            set_source_files_properties("${CMKR_TEMP_FILE}" PROPERTIES
+                CMKR_CURRENT_LIST_FILE "${CMAKE_CURRENT_LIST_FILE}"
+            )
+            
+            # 'Execute' the newly-generated CMakeLists.txt
+            include("${CMKR_TEMP_FILE}")
+            
+            # Delete the generated file
+            file(REMOVE "${CMKR_TEMP_FILE}")
+            
+            # Do not execute the rest of the original CMakeLists.txt
+            return()
+        endif()
+        # Resume executing the unmodified CMakeLists.txt
+    endif()
+endmacro()

src/main.cpp

@@ -0,0 +1 @@
+// private entity