Core: Fix portable mode on macOS

CHANGES

@@ -15,6 +15,7 @@ Other fixes:
  - ARM Debugger: Fix disassembly alignment (fixes mgba.io/i/2204)
  - Core: Fix memory leak in opening games from the library
  - Core: Fix memory searches for relative values (fixes mgba.io/i/2135)
+ - Core: Fix portable mode on macOS
  - GB Core: Fix GBC colors setting breaking default model overrides (fixes mgba.io/i/2161)
  - GBA: Fix out of bounds ROM accesses on patched ROMs smaller than 32 MiB
  - Qt: Fix infrequent deadlock when using sync to video

CMakeLists.txt

@@ -228,6 +228,7 @@ endif()
 
 if(APPLE)
 	add_definitions(-D_DARWIN_C_SOURCE)
+	list(APPEND OS_LIB "-framework Foundation")
 	if(CMAKE_SYSTEM_VERSION VERSION_GREATER "10.5.8")
 		set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mmacosx-version-min=10.6")
 	endif()

src/core/config.c

@@ -19,6 +19,12 @@
 #include <strsafe.h>
 #endif
 
+#ifdef __APPLE__
+#include <CoreFoundation/CFBundle.h>
+#include <CoreFoundation/CFString.h>
+#include <CoreFoundation/CFURL.h>
+#endif
+
 #ifdef PSP2
 #include <psp2/io/stat.h>
 #endif
@@ -274,6 +280,16 @@ void mCoreConfigPortablePath(char* out, size_t outLength) {
 	out[0] = '\0';
 #else
 	getcwd(out, outLength);
+#ifdef __APPLE__
+	CFBundleRef mainBundle = CFBundleGetMainBundle();
+	if (strcmp(out, "/") == 0 && mainBundle) {
+		CFURLRef url = CFBundleCopyBundleURL(mainBundle);
+		CFURLRef suburl = CFURLCreateCopyDeletingLastPathComponent(kCFAllocatorDefault, url);
+		CFRelease(url);
+		CFURLGetFileSystemRepresentation(suburl, true, (UInt8*) out, outLength);
+		CFRelease(suburl);
+	}
+#endif
 	strncat(out, PATH_SEP "portable.ini", outLength - strlen(out));
 #endif
 }