macos: Add wrapper API to run a NSApplication in the main thread

On macOS, a Cocoa event loop is needed in the main thread to ensure
things like opening a GL window work correctly. In the past, this was
patched into glib via Cerbero, but that prevented us from updating it.
This workaround simply runs an NSApplication and then calls the
main function on a secondary thread, allowing GStreamer to correctly
display windows and/or system permission prompts, for example.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3532>

subprojects/gst-docs/examples/tutorials/basic-tutorial-1.c

@@ -1,7 +1,11 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline;
   GstBus *bus;
@@ -38,3 +42,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-12.c

@@ -1,6 +1,10 @@
 #include <gst/gst.h>
 #include <string.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 typedef struct _CustomData
 {
   gboolean is_live;
@@ -59,7 +63,7 @@ cb_message (GstBus * bus, GstMessage * msg, CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline;
   GstBus *bus;
@@ -106,3 +110,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-13.c

@@ -2,6 +2,10 @@
 #include <stdio.h>
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 typedef struct _CustomData
 {
   GstElement *pipeline;
@@ -103,7 +107,7 @@ handle_keyboard (GIOChannel * source, GIOCondition cond, CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstStateChangeReturn ret;
@@ -160,3 +164,13 @@ main (int argc, char *argv[])
   gst_object_unref (data.pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-15.c

@@ -1,5 +1,9 @@
 #include <clutter-gst/clutter-gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Setup the video texture once its size is known */
 void
 size_change (ClutterActor * texture, gint width, gint height,
@@ -42,7 +46,7 @@ size_change (ClutterActor * texture, gint width, gint height,
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline, *sink;
   ClutterTimeline *timeline;
@@ -106,3 +110,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-2.c

@@ -1,7 +1,11 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline, *source, *sink;
   GstBus *bus;
@@ -80,3 +84,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-3.c

@@ -1,5 +1,9 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Structure to contain all our information, so we can pass it to callbacks */
 typedef struct _CustomData
 {
@@ -15,7 +19,7 @@ static void pad_added_handler (GstElement * src, GstPad * pad,
     CustomData * data);
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstBus *bus;
@@ -166,3 +170,13 @@ exit:
   /* Unreference the sink pad */
   gst_object_unref (sink_pad);
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-4.c

@@ -1,5 +1,9 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Structure to contain all our information, so we can pass it around */
 typedef struct _CustomData
 {
@@ -15,7 +19,7 @@ typedef struct _CustomData
 static void handle_message (CustomData * data, GstMessage * msg);
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstBus *bus;
@@ -170,3 +174,13 @@ handle_message (CustomData * data, GstMessage * msg)
   }
   gst_message_unref (msg);
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-5.c

@@ -4,6 +4,10 @@
 #include <gst/gst.h>
 #include <gst/video/videooverlay.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 #include <gdk/gdk.h>
 #if defined (GDK_WINDOWING_X11)
 #include <gdk/gdkx.h>
@@ -372,7 +376,7 @@ application_cb (GstBus * bus, GstMessage * msg, CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstStateChangeReturn ret;
@@ -443,3 +447,13 @@ main (int argc, char *argv[])
   gst_object_unref (data.playbin);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-6.c

@@ -1,5 +1,9 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Functions below print the Capabilities in a human-friendly format */
 static gboolean
 print_field (GQuark field, const GValue * value, gpointer pfx)
@@ -110,7 +114,7 @@ print_pad_capabilities (GstElement * element, gchar * pad_name)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline, *source, *sink;
   GstElementFactory *source_factory, *sink_factory;
@@ -222,3 +226,13 @@ main (int argc, char *argv[])
   gst_object_unref (sink_factory);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-7.c

@@ -1,7 +1,11 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline, *audio_source, *tee, *audio_queue, *audio_convert,
       *audio_resample, *audio_sink;
@@ -96,3 +100,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-8.c

@@ -2,6 +2,10 @@
 #include <gst/audio/audio.h>
 #include <string.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 #define CHUNK_SIZE 1024         /* Amount of bytes we are sending in each buffer */
 #define SAMPLE_RATE 44100       /* Samples per second we are sending */
 
@@ -134,7 +138,7 @@ error_cb (GstBus * bus, GstMessage * msg, CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstPad *tee_audio_pad, *tee_video_pad, *tee_app_pad;
@@ -268,3 +272,13 @@ main (int argc, char *argv[])
   gst_object_unref (data.pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/basic-tutorial-9.c

@@ -2,6 +2,10 @@
 #include <gst/gst.h>
 #include <gst/pbutils/pbutils.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Structure to contain all our information, so we can pass it around */
 typedef struct _CustomData
 {
@@ -181,7 +185,7 @@ on_finished_cb (GstDiscoverer * discoverer, CustomData * data)
 }
 
 int
-main (int argc, char **argv)
+tutorial_main (int argc, char **argv)
 {
   CustomData data;
   GError *err = NULL;
@@ -238,3 +242,13 @@ main (int argc, char **argv)
 
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-1.c

@@ -1,6 +1,10 @@
 #include <stdio.h>
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Structure to contain all our information, so we can pass it around */
 typedef struct _CustomData
 {
@@ -32,7 +36,7 @@ static gboolean handle_keyboard (GIOChannel * source, GIOCondition cond,
     CustomData * data);
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstBus *bus;
@@ -240,3 +244,13 @@ handle_keyboard (GIOChannel * source, GIOCondition cond, CustomData * data)
   g_free (str);
   return TRUE;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-2.c

@@ -1,6 +1,10 @@
 #include <stdio.h>
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* Structure to contain all our information, so we can pass it around */
 typedef struct _CustomData
 {
@@ -32,7 +36,7 @@ static gboolean handle_keyboard (GIOChannel * source, GIOCondition cond,
     CustomData * data);
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstBus *bus;
@@ -244,3 +248,13 @@ handle_keyboard (GIOChannel * source, GIOCondition cond, CustomData * data)
   g_free (str);
   return TRUE;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-3.c

@@ -2,6 +2,10 @@
 #include <gst/audio/audio.h>
 #include <string.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 #define CHUNK_SIZE 1024         /* Amount of bytes we are sending in each buffer */
 #define SAMPLE_RATE 44100       /* Samples per second we are sending */
 
@@ -133,7 +137,7 @@ source_setup (GstElement * pipeline, GstElement * source, CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstBus *bus;
@@ -170,3 +174,13 @@ main (int argc, char *argv[])
   gst_object_unref (data.pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-4.c

@@ -1,6 +1,10 @@
 #include <gst/gst.h>
 #include <string.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 #define GRAPH_LENGTH 78
 
 /* playbin flags */
@@ -122,7 +126,7 @@ refresh_ui (CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline;
   GstBus *bus;
@@ -186,3 +190,13 @@ main (int argc, char *argv[])
   g_print ("\n");
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-5.c

@@ -3,6 +3,10 @@
 #include <gst/gst.h>
 #include <gst/video/colorbalance.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 typedef struct _CustomData
 {
   GstElement *pipeline;
@@ -109,7 +113,7 @@ handle_keyboard (GIOChannel * source, GIOCondition cond, CustomData * data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   CustomData data;
   GstStateChangeReturn ret;
@@ -163,3 +167,13 @@ main (int argc, char *argv[])
   gst_object_unref (data.pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-6.c

@@ -1,5 +1,9 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 /* playbin2 flags */
 typedef enum
 {
@@ -22,7 +26,7 @@ filter_vis_features (GstPluginFeature * feature, gpointer data)
 }
 
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline, *vis_plugin;
   GstBus *bus;
@@ -99,3 +103,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gst-docs/examples/tutorials/playback-tutorial-7.c

@@ -1,7 +1,11 @@
 #include <gst/gst.h>
 
+#ifdef __APPLE__
+#include <TargetConditionals.h>
+#endif
+
 int
-main (int argc, char *argv[])
+tutorial_main (int argc, char *argv[])
 {
   GstElement *pipeline, *bin, *equalizer, *convert, *sink;
   GstPad *pad, *ghost_pad;
@@ -60,3 +64,13 @@ main (int argc, char *argv[])
   gst_object_unref (pipeline);
   return 0;
 }
+
+int
+main (int argc, char *argv[])
+{
+#if defined(__APPLE__) && TARGET_OS_MAC && !TARGET_OS_IPHONE
+  return gst_macos_main (tutorial_main, argc, argv, NULL);
+#else
+  return tutorial_main (argc, argv);
+#endif
+}

subprojects/gstreamer/gst/gst.h

@@ -95,6 +95,13 @@
 /* API compatibility stuff */
 #include <gst/gstcompat.h>
 
+#ifdef __APPLE__
+#	include <TargetConditionals.h>
+#	if TARGET_OS_MAC && !TARGET_OS_IPHONE
+#	 include <gst/gstmacos.h>
+#	endif
+#endif
+
 G_BEGIN_DECLS
 
 GST_API

subprojects/gstreamer/gst/gstmacos.h

@@ -0,0 +1,43 @@
+#ifndef __GST_MACOS_H__
+#define __GST_MACOS_H__
+
+#include <gst/gstconfig.h>
+#include <gst/glib-compat.h>
+
+G_BEGIN_DECLS
+
+/**
+ * GstMainFunc:
+ * @argc: the amount of arguments passed in @argv
+ * @argv: (array length=argc): an array of arguments passed to the main function
+ * @user_data: (nullable): user data passed to the main function
+ *
+ * Represents a simple pointer to the main() function of a program.
+ * It is used to pass that function along with its arguments to
+ * gst_macos_main(), which ensures correct behaviour of various
+ * GStreamer elements (e.g glimagesink) on macOS.
+ */
+typedef int (*GstMainFunc) (int argc, char** argv, gpointer user_data);
+
+/**
+ * GstMainFuncSimple:
+ * @user_data: (nullable): user data passed to the main function
+ *
+ * Simplified version of #GstMainFunc, meant to be used with
+ * gst_macos_main_simple(), which does not require argc/argv to be passed.
+ */
+typedef int (*GstMainFuncSimple) (gpointer user_data);
+
+GST_API
+int              gst_macos_main                   (GstMainFunc main_func,
+                                                   int argc,
+                                                   char *argv[],
+                                                   gpointer user_data);
+
+GST_API
+int              gst_macos_main_simple            (GstMainFuncSimple main_func,
+                                                   gpointer user_data);
+
+G_END_DECLS
+
+#endif /* __GST_MACOS_H__ */

subprojects/gstreamer/gst/gstmacos.m

@@ -0,0 +1,101 @@
+#include "gstmacos.h"
+#include <Cocoa/Cocoa.h>
+
+typedef struct _ThreadArgs ThreadArgs;
+
+struct _ThreadArgs {
+  void* main_func;
+  int argc;
+  char **argv;
+  gpointer user_data;
+  gboolean is_simple;
+};
+
+int
+gst_thread_func (ThreadArgs *args)
+{
+  int ret;
+  if (args->is_simple) {
+    ret = ((GstMainFuncSimple) args->main_func) (args->user_data);
+  } else {
+    ret = ((GstMainFunc) args->main_func) (args->argc, args->argv, args->user_data);
+  }
+
+  [NSApp terminate: nil];
+  return ret;
+}
+
+int
+run_main_with_nsapp (ThreadArgs args)
+{
+  GThread *gst_thread;
+
+  [NSApplication sharedApplication]; 
+  gst_thread = g_thread_new ("macos-gst-thread", (GThreadFunc) gst_thread_func, &args);
+  [NSApp run];
+
+  return GPOINTER_TO_INT (g_thread_join (gst_thread));
+}
+
+/**
+ * gst_macos_main:
+ * @main_func: (scope async): pointer to the main function to be called
+ * @argc: the amount of arguments passed in @argv
+ * @argv: (array length=argc): an array of arguments to be passed to the main function
+ * @user_data: (nullable): user data to be passed to the main function
+ *
+ * Starts an NSApplication on the main thread before calling 
+ * the provided main() function on a secondary thread. 
+ * 
+ * This ensures that GStreamer can correctly perform actions 
+ * such as creating a GL window, which require a Cocoa main loop 
+ * to be running on the main thread.
+ *
+ * Do not call this function more than once - especially while
+ * another one is still running - as that will cause unpredictable
+ * behaviour and most likely completely fail.
+ *
+ * Returns: the return value of the provided main_func
+ *
+ * Since: 1.22
+ */
+int
+gst_macos_main (GstMainFunc main_func, int argc, char **argv, gpointer user_data)
+{
+  ThreadArgs args;
+
+  args.argc = argc;
+  args.argv = argv;
+  args.main_func = main_func;
+  args.user_data = user_data;
+  args.is_simple = FALSE;
+
+  return run_main_with_nsapp (args);
+}
+
+/**
+ * gst_macos_main_simple:
+ * @main_func: (scope async): pointer to the main function to be called
+ * @user_data: (nullable): user data to be passed to the main function
+ *
+ * Simplified variant of gst_macos_main(), meant to be used with bindings
+ * for languages which do not have to pass argc and argv like C does.
+ * See gst_macos_main() for a more detailed description.
+ *
+ * Returns: the return value of the provided main_func
+ *
+ * Since: 1.22
+ */
+int 
+gst_macos_main_simple (GstMainFuncSimple main_func, gpointer user_data)
+{
+  ThreadArgs args;
+
+  args.argc = 0;
+  args.argv = NULL;
+  args.main_func = main_func;
+  args.user_data = user_data;
+  args.is_simple = TRUE;
+
+  return run_main_with_nsapp (args);
+}

subprojects/gstreamer/gst/meson.build

@@ -148,6 +148,11 @@ gst_headers = files(
   'gstparse.h',
   'math-compat.h',
 )
+if host_system == 'darwin'
+  gst_headers += 'gstmacos.h'
+  gst_sources += 'gstmacos.m'
+endif
+
 install_headers(gst_headers, subdir : 'gstreamer-1.0/gst')
 
 extra_deps = []
@@ -156,6 +161,10 @@ if host_system == 'android'
   extra_deps += cc.find_library('log')
 endif
 
+if host_system == 'darwin'
+  extra_deps += dependency('appleframeworks', modules : ['Cocoa'])
+endif
+
 gst_registry = get_option('registry')
 if gst_registry
   gst_registry_sources = files('gstregistrybinary.c')

subprojects/gstreamer/meson.build

@@ -16,8 +16,6 @@ else
 endif
 gst_version_is_dev = gst_version_minor % 2 == 1 and gst_version_micro < 90
 
-host_system = host_machine.system()
-
 apiversion = '1.0'
 soversion = 0
 # maintaining compatibility with the previous libtool versioning
@@ -33,6 +31,19 @@ libexecdir = get_option('libexecdir')
 helpers_install_dir = join_paths(libexecdir, 'gstreamer-1.0')
 
 cc = meson.get_compiler('c')
+host_system = host_machine.system()
+
+if host_system == 'darwin'
+  ios_test_code = '''#include <TargetConditionals.h>
+  #if ! TARGET_OS_IPHONE
+  #error "Not iOS/tvOS/watchOS/iPhoneSimulator"
+  #endif'''
+  if cc.compiles(ios_test_code, name : 'building for iOS')
+    host_system = 'ios'
+  endif
+
+  add_languages('objc', native: false, required: true)
+endif
 
 cdata = configuration_data()