cmake: optionally generate tweakme header

CMakeLists.txt

@@ -95,6 +95,7 @@ option(SPDLOG_BUILD_WARNINGS "Enable compiler warnings" OFF)
 # install options
 option(SPDLOG_SYSTEM_INCLUDES "Include as system headers (skip for clang-tidy)." OFF)
 option(SPDLOG_INSTALL "Generate the install target" ${SPDLOG_MASTER_PROJECT})
+option(SPDLOG_GENERATE_TWEAKME_H "Generate tweakme.h from the CMake configuration" OFF)
 option(SPDLOG_USE_STD_FORMAT "Use std::format instead of fmt library." OFF)
 option(SPDLOG_FMT_EXTERNAL "Use external fmt library instead of bundled" OFF)
 option(SPDLOG_FMT_EXTERNAL_HO "Use external fmt header-only library instead of bundled" OFF)
@@ -144,6 +145,19 @@ option(
 option(SPDLOG_DISABLE_DEFAULT_LOGGER "Disable default logger creation" OFF)
 option(SPDLOG_FWRITE_UNLOCKED "Use the unlocked variant of fwrite. Leave this on unless your libc doesn't have it" ON)
 
+set(SPDLOG_WCHAR_TO_UTF8_SUPPORT ${SPDLOG_WCHAR_SUPPORT})
+set(SPDLOG_UTF8_TO_WCHAR_CONSOLE ${SPDLOG_WCHAR_CONSOLE})
+
+if(SPDLOG_GENERATE_TWEAKME_H)
+    if(SPDLOG_FMT_EXTERNAL OR SPDLOG_FMT_EXTERNAL_HO)
+        set(SPDLOG_TWEAKME_FMT_EXTERNAL_DEFINITION "#define SPDLOG_FMT_EXTERNAL")
+    else()
+        set(SPDLOG_TWEAKME_FMT_EXTERNAL_DEFINITION "/* #undef SPDLOG_FMT_EXTERNAL */")
+    endif()
+    file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/include/spdlog")
+    configure_file(cmake/tweakme.h.in "${CMAKE_CURRENT_BINARY_DIR}/include/spdlog/tweakme.h" @ONLY)
+endif()
+
 # clang-tidy
 option(SPDLOG_TIDY "run clang-tidy" OFF)
 
@@ -194,6 +208,10 @@ if(SPDLOG_SYSTEM_INCLUDES)
 endif()
 
 target_compile_definitions(spdlog PUBLIC SPDLOG_COMPILED_LIB)
+if(SPDLOG_GENERATE_TWEAKME_H)
+    target_include_directories(
+        spdlog ${SPDLOG_INCLUDES_LEVEL} BEFORE PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>")
+endif()
 target_include_directories(spdlog ${SPDLOG_INCLUDES_LEVEL} PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
                                                                   "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
 target_link_libraries(spdlog PUBLIC Threads::Threads)
@@ -221,6 +239,11 @@ endif()
 add_library(spdlog_header_only INTERFACE)
 add_library(spdlog::spdlog_header_only ALIAS spdlog_header_only)
 
+if(SPDLOG_GENERATE_TWEAKME_H)
+    target_include_directories(
+        spdlog_header_only ${SPDLOG_INCLUDES_LEVEL} BEFORE INTERFACE
+        "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}/include>")
+endif()
 target_include_directories(
     spdlog_header_only ${SPDLOG_INCLUDES_LEVEL} INTERFACE "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}/include>"
                                                           "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>")
@@ -275,8 +298,6 @@ endif()
 # ---------------------------------------------------------------------------------------
 # Misc definitions according to tweak options
 # ---------------------------------------------------------------------------------------
-set(SPDLOG_WCHAR_TO_UTF8_SUPPORT ${SPDLOG_WCHAR_SUPPORT})
-set(SPDLOG_UTF8_TO_WCHAR_CONSOLE ${SPDLOG_WCHAR_CONSOLE})
 foreach(
     SPDLOG_OPTION
     SPDLOG_WCHAR_TO_UTF8_SUPPORT
@@ -363,7 +384,14 @@ if(SPDLOG_INSTALL)
     # ---------------------------------------------------------------------------------------
     # Include files
     # ---------------------------------------------------------------------------------------
-    install(DIRECTORY include/ DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}" PATTERN "fmt/bundled" EXCLUDE)
+    if(SPDLOG_GENERATE_TWEAKME_H)
+        install(DIRECTORY include/ DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}" PATTERN "fmt/bundled" EXCLUDE
+                PATTERN "tweakme.h" EXCLUDE)
+        install(FILES "${CMAKE_CURRENT_BINARY_DIR}/include/spdlog/tweakme.h"
+                DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/spdlog")
+    else()
+        install(DIRECTORY include/ DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}" PATTERN "fmt/bundled" EXCLUDE)
+    endif()
     install(
         TARGETS spdlog spdlog_header_only
         EXPORT spdlog

cmake/tweakme.h.in

@@ -0,0 +1,25 @@
+// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
+// Distributed under the MIT License (http://opensource.org/licenses/MIT)
+
+#pragma once
+
+// Generated by CMake. Configure spdlog with SPDLOG_GENERATE_TWEAKME_H=OFF to
+// use the editable source-tree tweakme.h instead.
+
+#define SPDLOG_TWEAKME_H_GENERATED 1
+
+#cmakedefine SPDLOG_CLOCK_COARSE
+#cmakedefine SPDLOG_NO_THREAD_ID
+#cmakedefine SPDLOG_NO_TLS
+#cmakedefine SPDLOG_NO_ATOMIC_LEVELS
+#cmakedefine SPDLOG_WCHAR_FILENAMES
+
+@SPDLOG_TWEAKME_FMT_EXTERNAL_DEFINITION@
+
+#cmakedefine SPDLOG_USE_STD_FORMAT
+#cmakedefine SPDLOG_WCHAR_TO_UTF8_SUPPORT
+#cmakedefine SPDLOG_UTF8_TO_WCHAR_CONSOLE
+#cmakedefine SPDLOG_PREVENT_CHILD_FD
+#cmakedefine SPDLOG_DISABLE_DEFAULT_LOGGER
+#cmakedefine SPDLOG_NO_EXCEPTIONS
+#cmakedefine SPDLOG_NO_TZ_OFFSET

tests/CMakeLists.txt

@@ -94,3 +94,14 @@ endif()
 if(SPDLOG_BUILD_TESTS_HO OR SPDLOG_BUILD_ALL)
     spdlog_prepare_test(spdlog-utests-ho spdlog::spdlog_header_only)
 endif()
+
+if(SPDLOG_MASTER_PROJECT AND NOT CMAKE_CROSSCOMPILING)
+    add_test(
+        NAME spdlog-cmake-tweakme
+        COMMAND
+            ${CMAKE_COMMAND} -DSPDLOG_TEST_SOURCE_DIR=${CMAKE_CURRENT_LIST_DIR}/..
+            -DSPDLOG_TEST_BINARY_DIR=${CMAKE_CURRENT_BINARY_DIR}/cmake-tweakme
+            -DSPDLOG_TEST_GENERATOR=${CMAKE_GENERATOR} -DSPDLOG_TEST_GENERATOR_PLATFORM=${CMAKE_GENERATOR_PLATFORM}
+            -DSPDLOG_TEST_GENERATOR_TOOLSET=${CMAKE_GENERATOR_TOOLSET} -DSPDLOG_TEST_CXX_COMPILER=${CMAKE_CXX_COMPILER}
+            -DSPDLOG_TEST_CONFIG=$<CONFIG> -P ${CMAKE_CURRENT_LIST_DIR}/cmake/tweakme_test.cmake)
+endif()

tests/cmake/tweakme/CMakeLists.txt

@@ -0,0 +1,37 @@
+cmake_minimum_required(VERSION 3.10)
+project(spdlog_tweakme_consumer LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+if(SPDLOG_TEST_INSTALLED)
+    find_package(spdlog CONFIG REQUIRED)
+
+    add_executable(package-compiled main.cpp)
+    target_link_libraries(package-compiled PRIVATE spdlog::spdlog)
+
+    add_executable(package-header-only main.cpp)
+    target_link_libraries(package-header-only PRIVATE spdlog::spdlog_header_only)
+
+    find_package(Threads REQUIRED)
+    add_executable(raw-header-only main.cpp)
+    target_include_directories(raw-header-only PRIVATE "${SPDLOG_TEST_PREFIX}/include")
+    target_link_libraries(raw-header-only PRIVATE Threads::Threads)
+else()
+    set(SPDLOG_GENERATE_TWEAKME_H ON CACHE BOOL "" FORCE)
+    set(SPDLOG_NO_THREAD_ID ON CACHE BOOL "" FORCE)
+    set(SPDLOG_NO_TLS ON CACHE BOOL "" FORCE)
+    set(SPDLOG_DISABLE_DEFAULT_LOGGER ON CACHE BOOL "" FORCE)
+    set(SPDLOG_BUILD_SHARED ${SPDLOG_TEST_SHARED} CACHE BOOL "" FORCE)
+    set(SPDLOG_BUILD_EXAMPLE OFF CACHE BOOL "" FORCE)
+    set(SPDLOG_BUILD_TESTS OFF CACHE BOOL "" FORCE)
+    set(SPDLOG_INSTALL ON CACHE BOOL "" FORCE)
+    add_subdirectory("${SPDLOG_TEST_SOURCE_DIR}" spdlog)
+
+    add_executable(source-compiled main.cpp)
+    target_link_libraries(source-compiled PRIVATE spdlog::spdlog)
+
+    add_executable(source-header-only main.cpp)
+    target_link_libraries(source-header-only PRIVATE spdlog::spdlog_header_only)
+endif()

tests/cmake/tweakme/main.cpp

@@ -0,0 +1,19 @@
+#include <spdlog/spdlog.h>
+
+#ifndef SPDLOG_TWEAKME_H_GENERATED
+#error The generated tweakme.h must be selected before the source header
+#endif
+
+#ifndef SPDLOG_NO_THREAD_ID
+#error SPDLOG_NO_THREAD_ID must be provided by the generated tweakme.h
+#endif
+
+#ifndef SPDLOG_NO_TLS
+#error SPDLOG_NO_TLS must be provided by the generated tweakme.h
+#endif
+
+#ifndef SPDLOG_DISABLE_DEFAULT_LOGGER
+#error SPDLOG_DISABLE_DEFAULT_LOGGER must be provided by the generated tweakme.h
+#endif
+
+int main() { return 0; }

tests/cmake/tweakme_test.cmake

@@ -0,0 +1,66 @@
+function(run_checked description)
+    execute_process(COMMAND ${ARGN} RESULT_VARIABLE result OUTPUT_VARIABLE output ERROR_VARIABLE error)
+    if(NOT result EQUAL 0)
+        message(FATAL_ERROR "${description} failed (${result}):\n${output}\n${error}")
+    endif()
+endfunction()
+
+function(configure_checked description source_dir build_dir)
+    file(MAKE_DIRECTORY "${build_dir}")
+    execute_process(
+        COMMAND "${CMAKE_COMMAND}" ${ARGN} "${source_dir}"
+        WORKING_DIRECTORY "${build_dir}"
+        RESULT_VARIABLE result
+        OUTPUT_VARIABLE output
+        ERROR_VARIABLE error)
+    if(NOT result EQUAL 0)
+        message(FATAL_ERROR "${description} failed (${result}):\n${output}\n${error}")
+    endif()
+endfunction()
+
+function(test_tweakme_configuration library_type shared)
+    set(build_dir "${SPDLOG_TEST_BINARY_DIR}/${library_type}/build")
+    set(prefix "${SPDLOG_TEST_BINARY_DIR}/${library_type}/prefix")
+    set(consumer_dir "${SPDLOG_TEST_BINARY_DIR}/${library_type}/consumer")
+    file(REMOVE_RECURSE "${SPDLOG_TEST_BINARY_DIR}/${library_type}")
+
+    set(generator_args -G "${SPDLOG_TEST_GENERATOR}")
+    if(SPDLOG_TEST_GENERATOR_PLATFORM)
+        list(APPEND generator_args -A "${SPDLOG_TEST_GENERATOR_PLATFORM}")
+    endif()
+    if(SPDLOG_TEST_GENERATOR_TOOLSET)
+        list(APPEND generator_args -T "${SPDLOG_TEST_GENERATOR_TOOLSET}")
+    endif()
+
+    set(common_args
+        "-DCMAKE_CXX_COMPILER=${SPDLOG_TEST_CXX_COMPILER}"
+        "-DCMAKE_BUILD_TYPE=${SPDLOG_TEST_CONFIG}")
+
+    configure_checked(
+        "Configure ${library_type} source-tree consumer"
+        "${CMAKE_CURRENT_LIST_DIR}/tweakme" "${build_dir}" ${generator_args} ${common_args}
+        "-DSPDLOG_TEST_SOURCE_DIR=${SPDLOG_TEST_SOURCE_DIR}" "-DSPDLOG_TEST_SHARED=${shared}"
+        "-DCMAKE_INSTALL_PREFIX=${prefix}")
+    run_checked("Build ${library_type} source-tree consumer" "${CMAKE_COMMAND}" --build "${build_dir}" --config
+                "${SPDLOG_TEST_CONFIG}")
+    run_checked("Install ${library_type} spdlog" "${CMAKE_COMMAND}" --build "${build_dir}" --target install --config
+                "${SPDLOG_TEST_CONFIG}")
+
+    set(installed_tweakme "${prefix}/include/spdlog/tweakme.h")
+    file(READ "${installed_tweakme}" tweakme_contents)
+    foreach(expected_macro SPDLOG_NO_THREAD_ID SPDLOG_NO_TLS SPDLOG_DISABLE_DEFAULT_LOGGER)
+        if(NOT tweakme_contents MATCHES "#define ${expected_macro}([\r\n]|$)")
+            message(FATAL_ERROR "${installed_tweakme} does not define ${expected_macro}")
+        endif()
+    endforeach()
+
+    configure_checked(
+        "Configure ${library_type} installed consumers"
+        "${CMAKE_CURRENT_LIST_DIR}/tweakme" "${consumer_dir}" ${generator_args} ${common_args}
+        -DSPDLOG_TEST_INSTALLED=ON "-DSPDLOG_TEST_PREFIX=${prefix}" "-DCMAKE_PREFIX_PATH=${prefix}")
+    run_checked("Build ${library_type} installed consumers" "${CMAKE_COMMAND}" --build "${consumer_dir}" --config
+                "${SPDLOG_TEST_CONFIG}")
+endfunction()
+
+test_tweakme_configuration(static OFF)
+test_tweakme_configuration(shared ON)