cmake: use FindALSA.cmake to find ALSA library

.gitignore

@@ -62,6 +62,11 @@ cmake-build-*
 xcuserdata
 *.xcworkspace
 
+# for QtCreator
+CMakeLists.txt.user
+build*/
+*.pro.user*
+
 # for Visual C++
 .vs
 Debug
@@ -173,6 +178,7 @@ test/testyuv
 test/torturethread
 
 builddir/
+!build-scripts/
 debian/*.debhelper.log
 debian/*.substvars
 debian/*.tar.gz

CMakeLists.txt

@@ -18,6 +18,9 @@ endif()
 set(EXTRA_LIBS)
 set(EXTRA_LDFLAGS)
 
+set(CMAKE_DEPENDS)
+set(PKGCONFIG_DEPENDS)
+
 # This is a virtual "library" that just exists to collect up compiler and
 #  linker options that used to be global to this CMake project. When you
 #  specify it as part of a real library's target_link_libraries(), that
@@ -27,7 +30,6 @@ set(EXTRA_LDFLAGS)
 add_library(sdl-build-options INTERFACE)
 
 if(WINDOWS_STORE)
-  cmake_minimum_required(VERSION 3.11.0)
   target_compile_definitions(sdl-build-options INTERFACE "-DSDL_BUILDING_WINRT=1")
   target_compile_options(sdl-build-options INTERFACE "-ZW")
 endif()
@@ -3074,6 +3076,7 @@ string(REGEX REPLACE "-lSDL2( |$)" "-l${sdl_static_libname} " SDL_STATIC_LIBS "$
 if(NOT SDL_SHARED)
   string(REGEX REPLACE "-lSDL2( |$)" "-l${sdl_static_libname} " SDL_LIBS "${SDL_LIBS}")
 endif()
+listtostr(PKGCONFIG_DEPENDS PKGCONFIG_DEPENDS)
 
 if(SDL_STATIC AND SDL_SHARED AND NOT sdl_static_libname STREQUAL "SDL2")
   message(STATUS "\"pkg-config --static --libs sdl2\" will return invalid information")
@@ -3154,7 +3157,7 @@ if (SDL_ASAN)
   endif()
 endif()
 
-if(SDL_CCACHE)
+if(SDL_CCACHE AND NOT CMAKE_VERSION VERSION_LESS 3.4)
   cmake_minimum_required(VERSION 3.4)
   find_program(CCACHE_BINARY ccache)
   if(CCACHE_BINARY)
@@ -3165,6 +3168,8 @@ if(SDL_CCACHE)
   else()
     set(HAVE_CCACHE OFF)
   endif()
+else()
+  set(HAVE_CCACHE OFF)
 endif()
 
 if(SDL_TESTS)
@@ -3334,12 +3339,13 @@ if(SDL_SHARED)
     set_target_properties(SDL2 PROPERTIES STATIC_LIBRARY_FLAGS "/NODEFAULTLIB")
   endif()
   # FIXME: if CMAKE_VERSION >= 3.13, use target_link_options for EXTRA_LDFLAGS
-  target_link_libraries(SDL2 PRIVATE ${EXTRA_LIBS} ${EXTRA_LDFLAGS} ${EXTRA_LDFLAGS_BUILD})
+  target_link_libraries(SDL2 PRIVATE ${EXTRA_LIBS} ${EXTRA_LDFLAGS} ${EXTRA_LDFLAGS_BUILD} ${CMAKE_DEPENDS})
   target_include_directories(SDL2 PUBLIC
       "$<BUILD_INTERFACE:${SDL2_BINARY_DIR}/include>"
       "$<BUILD_INTERFACE:${SDL2_BINARY_DIR}/include-config-$<LOWER_CASE:$<CONFIG>>>"
       "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>"
-      "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/SDL2>")
+      "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/SDL2>"
+  )
   # This picks up all the compiler options and such we've accumulated up to here.
   target_link_libraries(SDL2 PRIVATE $<BUILD_INTERFACE:sdl-build-options>)
   if(MINGW OR CYGWIN)
@@ -3366,12 +3372,13 @@ if(SDL_STATIC)
   target_compile_definitions(SDL2-static PRIVATE SDL_STATIC_LIB)
   # TODO: Win32 platforms keep the same suffix .lib for import and static
   # libraries - do we need to consider this?
-  target_link_libraries(SDL2-static PRIVATE ${EXTRA_LIBS} ${EXTRA_LDFLAGS})
+  target_link_libraries(SDL2-static PRIVATE ${EXTRA_LIBS} ${EXTRA_LDFLAGS} ${CMAKE_DEPENDS})
   target_include_directories(SDL2-static PUBLIC
       "$<BUILD_INTERFACE:${SDL2_BINARY_DIR}/include>"
       "$<BUILD_INTERFACE:${SDL2_BINARY_DIR}/include-config-$<LOWER_CASE:$<CONFIG>>>"
       "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>"
-      "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/SDL2>")
+      "$<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}/SDL2>"
+  )
   # This picks up all the compiler options and such we've accumulated up to here.
   target_link_libraries(SDL2-static PRIVATE $<BUILD_INTERFACE:sdl-build-options>)
   if(NOT ANDROID)
@@ -3505,6 +3512,7 @@ if(NOT SDL2_DISABLE_INSTALL)
     FILES
       ${CMAKE_CURRENT_BINARY_DIR}/SDL2Config.cmake
       ${CMAKE_CURRENT_BINARY_DIR}/SDL2ConfigVersion.cmake
+      ${SDL2_SOURCE_DIR}/cmake/sdlfind.cmake
     DESTINATION "${SDL_INSTALL_CMAKEDIR}"
     COMPONENT Devel
   )

SDL2Config.cmake.in

@@ -30,6 +30,18 @@ if(EXISTS "${CMAKE_CURRENT_LIST_DIR}/SDL2testTargets.cmake")
   set(SDL2_SDL2test_FOUND TRUE)
 endif()
 
+
+include("${CMAKE_CURRENT_LIST_DIR}/sdlfind.cmake")
+
+set(SDL_ALSA @SDL_ALSA@)
+set(SDL_ALSA_SHARED @SDL_ALSA_SHARED@)
+if(SDL_ALSA AND NOT SDL_ALSA_SHARED AND TARGET SDL2::SDL2-static)
+  sdlFindALSA()
+endif()
+unset(SDL_ALSA)
+unset(SDL_ALSA_SHARED)
+
+
 check_required_components(SDL2)
 
 # Create SDL2::SDL2 alias for static-only builds

cmake/macros.cmake

@@ -29,7 +29,7 @@ ENDMACRO()
 
 # Message Output
 macro(MESSAGE_WARN _TEXT)
-  message(STATUS "*** WARNING: ${_TEXT}")
+  message(WARNING "${_TEXT}")
 endmacro()
 
 macro(MESSAGE_ERROR _TEXT)
@@ -64,7 +64,7 @@ macro(MESSAGE_TESTED_OPTION _NAME)
   message(STATUS "  ${_NAME}${_PAD}(Wanted: ${_REQVALUE}): ${HAVE_${_STRIPPEDNAME}}")
 endmacro()
 
-macro(LISTTOSTR _LIST _OUTPUT)
+function(LISTTOSTR _LIST _OUTPUT)
   if(${ARGC} EQUAL 3)
     # prefix for each element
     set(_LPREFIX ${ARGV2})
@@ -73,10 +73,12 @@ macro(LISTTOSTR _LIST _OUTPUT)
   endif()
   # Do not use string(REPLACE ";" " ") here to avoid messing up list
   # entries
+  set(res)
   foreach(_ITEM ${${_LIST}})
-    set(${_OUTPUT} "${${_OUTPUT}} ${_LPREFIX}${_ITEM}")
+    set(res "${res} ${_LPREFIX}${_ITEM}")
   endforeach()
-endmacro()
+  set(${_OUTPUT} "${res}" PARENT_SCOPE)
+endfunction()
 
 macro(LISTTOSTRREV _LIST _OUTPUT)
   if(${ARGC} EQUAL 3)

cmake/sdlchecks.cmake

@@ -1,4 +1,5 @@
 include(CMakeParseArguments)
+include(${SDL2_SOURCE_DIR}/cmake/sdlfind.cmake)
 macro(FindLibraryAndSONAME _LIB)
   cmake_parse_arguments(FLAS "" "" "LIBDIRS" ${ARGN})
 
@@ -6,6 +7,13 @@ macro(FindLibraryAndSONAME _LIB)
   string(REGEX REPLACE "\\-" "_" _LNAME "${_UPPERLNAME}")
 
   find_library(${_LNAME}_LIB ${_LIB} PATHS ${FLAS_LIBDIRS})
+
+  if(${_LNAME}_LIB MATCHES ".*\\${CMAKE_SHARED_LIBRARY_SUFFIX}.*" AND NOT ${_LNAME}_LIB MATCHES ".*\\${CMAKE_STATIC_LIBRARY_SUFFIX}.*")
+    set(${_LNAME}_SHARED TRUE)
+  else()
+    set(${_LNAME}_SHARED FALSE)
+  endif()
+
   if(${_LNAME}_LIB)
     # reduce the library name for shared linking
 
@@ -83,26 +91,35 @@ endmacro()
 # - HAVE_SDL_LOADSO opt
 macro(CheckALSA)
   if(SDL_ALSA)
-    CHECK_INCLUDE_FILE(alsa/asoundlib.h HAVE_ASOUNDLIB_H)
+    sdlFindALSA()
-    if(HAVE_ASOUNDLIB_H)
+    if(ALSA_FOUND)
-      CHECK_LIBRARY_EXISTS(asound snd_pcm_recover "" HAVE_LIBASOUND)
+      file(GLOB ALSA_SOURCES "${SDL2_SOURCE_DIR}/src/audio/alsa/*.c")
-    endif()
-    if(HAVE_LIBASOUND)
-      set(HAVE_ALSA TRUE)
-      file(GLOB ALSA_SOURCES ${SDL2_SOURCE_DIR}/src/audio/alsa/*.c)
       list(APPEND SOURCE_FILES ${ALSA_SOURCES})
       set(SDL_AUDIO_DRIVER_ALSA 1)
-      if(SDL_ALSA_SHARED AND NOT HAVE_SDL_LOADSO)
+      set(HAVE_ALSA TRUE)
-        message_warn("You must have SDL_LoadObject() support for dynamic ALSA loading")
+      set(HAVE_ALSA_SHARED FALSE)
-      endif()
+      if(SDL_ALSA_SHARED)
+        if(HAVE_SDL_LOADSO)
           FindLibraryAndSONAME("asound")
-      if(SDL_ALSA_SHARED AND ASOUND_LIB AND HAVE_SDL_LOADSO)
+          if(ASOUND_LIB AND ASOUND_SHARED)
+            target_include_directories(sdl-build-options INTERFACE $<TARGET_PROPERTY:ALSA::ALSA,INTERFACE_INCLUDE_DIRECTORIES>)
             set(SDL_AUDIO_DRIVER_ALSA_DYNAMIC "\"${ASOUND_LIB_SONAME}\"")
             set(HAVE_ALSA_SHARED TRUE)
           else()
-        list(APPEND EXTRA_LIBS asound)
+            message(WARNING "Unable to find asound shared object")
+          endif()
+        else()
+          message(WARNING "You must have SDL_LoadObject() support for dynamic ALSA loading")
+        endif()
+      endif()
+      if(NOT HAVE_ALSA_SHARED)
+        list(APPEND CMAKE_DEPENDS ALSA::ALSA)
+        list(APPEND PKGCONFIG_DEPENDS alsa)
       endif()
       set(HAVE_SDL_AUDIO TRUE)
+    else()
+      set(HAVE_ALSA FALSE)
+      message(WARNING "Unable to found the alsa development library")
     endif()
   endif()
 endmacro()

cmake/sdlfind.cmake

@@ -0,0 +1,9 @@
+
+macro(sdlFindALSA)
+  find_package(ALSA MODULE)
+  if(ALSA_FOUND AND (NOT TARGET ALSA::ALSA) )
+    add_Library(ALSA::ALSA UNKNOWN IMPORTED)
+    set_property(TARGET ALSA::ALSA PROPERTY INTERFACE_INCLUDE_DIRECTORIES ${ALSA_INCLUDE_DIRS})
+    set_property(TARGET ALSA::ALSA APPEND PROPERTY IMPORTED_LOCATION ${ALSA_LIBRARY})
+  endif()
+endmacro()

configure

@@ -677,6 +677,7 @@ ENABLE_STATIC_TRUE
 ENABLE_SHARED_FALSE
 ENABLE_SHARED_TRUE
 PKGCONFIG_LIBS_PRIV
+PKGCONFIG_DEPENDS
 SDL_RLD_FLAGS
 SDL_STATIC_LIBS
 SDL_LIBS
@@ -29873,6 +29874,8 @@ done
 
 
 
+PKGCONFIG_DEPENDS=""
+
 if test x$enable_shared = xyes; then
     PKGCONFIG_LIBS_PRIV="
 Libs.private:"

configure.ac

@@ -4861,6 +4861,8 @@ AC_SUBST(SDL_CFLAGS)
 AC_SUBST(SDL_LIBS)
 AC_SUBST(SDL_STATIC_LIBS)
 AC_SUBST(SDL_RLD_FLAGS)
+PKGCONFIG_DEPENDS=""
+AC_SUBST(PKGCONFIG_DEPENDS)
 if test x$enable_shared = xyes; then
     PKGCONFIG_LIBS_PRIV="
 Libs.private:"

sdl2.pc.in

@@ -8,7 +8,7 @@ includedir=@includedir@
 Name: sdl2
 Description: Simple DirectMedia Layer is a cross-platform multimedia library designed to provide low level access to audio, keyboard, mouse, joystick, 3D hardware via OpenGL, and 2D video framebuffer.
 Version: @SDL_VERSION@
-Requires:
+Requires.private: @PKGCONFIG_DEPENDS@
 Conflicts:
 Libs: -L${libdir} @SDL_RLD_FLAGS@ @SDL_LIBS@ @PKGCONFIG_LIBS_PRIV@ @SDL_STATIC_LIBS@
 Cflags: -I${includedir} -I${includedir}/SDL2 @SDL_CFLAGS@