iOS, FFmpeg: Modify FindFFmpeg.cmake to look for .xcframework files

Currently the FindFFmpeg.cmake script looks for the presence only
of .dylib files in order to determine the validity of the FFmpeg
installation. On iOS, we no longer deploy these file-types directly for
shared libraries. We only deploy .xcframework files, which in turn
contain the .dylibs. This creates a situation where FindFFmpeg can
succeed even when .xcframework files are missing from the FFmpeg
installation.

This patch allows FindFFmpeg.cmake to look for .xcframework files when
on iOS. This will also allow us to stop installing raw .dylibs as part
of FFmpeg builds.

Fixes: QTBUG-135172
Pick-to: 6.9 6.8
Change-Id: I215700dea7e2f8ee7e513c8dbaa0c850d4f41a03
Reviewed-by: Timur Pocheptsov <[email protected]>

Author: Didgy74

cmake/FindFFmpeg.cmake

@@ -70,6 +70,12 @@ if (QT_DEPLOY_FFMPEG AND BUILD_SHARED_LIBS)
     set(shared_libs_desired TRUE)
 endif()
 
+if(IOS)
+    set(QT_FFMPEG_SHARED_LIBRARY_SUFFIX ".xcframework")
+else()
+    set(QT_FFMPEG_SHARED_LIBRARY_SUFFIX "${CMAKE_SHARED_LIBRARY_SUFFIX}")
+endif()
+
 # finds FFmpeg libs, including symlinks, for the specified component.
 macro(find_shared_libs_for_component _component)
     # the searching pattern is pretty rough but it seems to be sufficient to gather dynamic libs
@@ -82,13 +88,13 @@ macro(find_shared_libs_for_component _component)
             # only them even though the folder bin/ contains proper *.dll and *.lib.
 
             string(REGEX REPLACE "^lib" "" name_we "${name_we}")
-            set(shared_lib_pattern "../bin/${name_we}*${CMAKE_SHARED_LIBRARY_SUFFIX}")
+            set(shared_lib_pattern "../bin/${name_we}*${QT_FFMPEG_SHARED_LIBRARY_SUFFIX}")
         else()
-            set(shared_lib_pattern "${name_we}*${CMAKE_SHARED_LIBRARY_SUFFIX}")
+            set(shared_lib_pattern "${name_we}*${QT_FFMPEG_SHARED_LIBRARY_SUFFIX}")
         endif()
 
     else()
-        set(shared_lib_pattern "${name_we}*${CMAKE_SHARED_LIBRARY_SUFFIX}*")
+        set(shared_lib_pattern "${name_we}*${QT_FFMPEG_SHARED_LIBRARY_SUFFIX}*")
     endif()
 
     file(GLOB ${_component}_SHARED_LIBRARIES "${${_component}_LIBRARY_DIR}/${shared_lib_pattern}")
@@ -155,25 +161,41 @@ macro(find_component _component _pkgconfig _library _header)
     )
 
     if (shared_libs_desired AND NOT WIN32)
-        set(CMAKE_FIND_LIBRARY_SUFFIXES "${CMAKE_SHARED_LIBRARY_SUFFIX};${CMAKE_STATIC_LIBRARY_SUFFIX}")
+        set(CMAKE_FIND_LIBRARY_SUFFIXES "${QT_FFMPEG_SHARED_LIBRARY_SUFFIX};${CMAKE_STATIC_LIBRARY_SUFFIX}")
     endif()
 
     if (${_component}_LIBRARY AND NOT EXISTS ${${_component}_LIBRARY})
         message(STATUS "Cached library ${${_component}_LIBRARY} doesn't exist")
         unset(${_component}_LIBRARY CACHE)
     endif()
 
-    find_library(${_component}_LIBRARY
-        NAMES ${PC_${_component}_LIBRARIES} ${_library}
-        HINTS
-            ${PC_${_component}_LIBDIR}
-            ${PC_${_component}_LIBRARY_DIRS}
-            ${PC_FFMPEG_LIBRARY_DIRS}
-        PATHS
-            ${FFMPEG_DIR}
-        PATH_SUFFIXES
-            lib bin
-    )
+    # Search for the relevant libraries. On iOS we deploy .xcframeworks, which aren't found by
+    # find_library, so we rely on find_path.
+    if (APPLE AND IOS)
+        find_path(${_component}_LIBRARY
+            NAMES lib${_library}${QT_FFMPEG_SHARED_LIBRARY_SUFFIX}
+            PATHS
+                ${FFMPEG_DIR}
+            PATH_SUFFIXES
+                lib bin framework
+        )
+        # If found, append the path with the file we were looking for.
+        if (${_component}_LIBRARY)
+            set(${_component}_LIBRARY "${${_component}_LIBRARY}/lib${_library}${QT_FFMPEG_SHARED_LIBRARY_SUFFIX}")
+        endif()
+    else()
+        find_library(${_component}_LIBRARY
+            NAMES ${PC_${_component}_LIBRARIES} ${_library}
+            HINTS
+                ${PC_${_component}_LIBDIR}
+                ${PC_${_component}_LIBRARY_DIRS}
+                ${PC_FFMPEG_LIBRARY_DIRS}
+            PATHS
+                ${FFMPEG_DIR}
+            PATH_SUFFIXES
+                lib bin
+        )
+    endif()
 
     if(FFMPEG_DIR OR FFMPEG_ROOT)
         set(CMAKE_FIND_ROOT_PATH "${__find_ffmpeg_backup_root_dir}")
@@ -185,7 +207,7 @@ macro(find_component _component _pkgconfig _library _header)
 
         # On Windows, shared linking goes through 'integration' static libs, so we should look for shared ones anyway
         # On Unix, we gather symlinks as well so that we could install them.
-        if (WIN32 OR ${${_component}_LIBRARY_NAME} MATCHES "\\${CMAKE_SHARED_LIBRARY_SUFFIX}$")
+        if (WIN32 OR ${${_component}_LIBRARY_NAME} MATCHES "\\${QT_FFMPEG_SHARED_LIBRARY_SUFFIX}$")
             find_shared_libs_for_component(${_component})
         endif()