player: drop explicit exit() calls

The code in main.c calls exit() explicitly, but the code is actually
easier to follow by simply exiting from main() instead. The exit() call
in av_log.c happens only on severely broken builds, so replace it with
abort().

(Shuts up rpmlint warnings.)

common/av_log.c

@@ -224,8 +224,8 @@ void print_libav_versions(struct mp_log *log, int v)
     if (broken) {
         mp_fatal(log, "mpv was compiled and linked against a mixture of Libav "
                  "and FFmpeg versions. This won't work and will most likely "
-                 "crash at some point. Exiting.\n");
-        exit(42);
+                 "crash at some point. Aborting.\n");
+        abort();
     }
     // We don't "really" support mismatched libraries, but if you like to
     // suffer, you're free to enjoy the terrible aspects of dynamic linking.

player/main.c

@@ -184,8 +184,7 @@ void mp_destroy(struct MPContext *mpctx)
     talloc_free(mpctx);
 }
 
-static MP_NORETURN void exit_player(struct MPContext *mpctx,
-                                    enum exit_reason how)
+static int prepare_exit_cplayer(struct MPContext *mpctx, enum exit_reason how)
 {
 #if HAVE_COCOA_APPLICATION
     cocoa_set_input_context(NULL);
@@ -230,13 +229,10 @@ static MP_NORETURN void exit_player(struct MPContext *mpctx,
     mp_destroy(mpctx);
 
 #if HAVE_COCOA_APPLICATION
+    // Note: this function never returns due to Cocoa calling exit(0)
     terminate_cocoa_application();
-    // never reach here:
-    // terminate calls exit itself, just silence compiler warning
-    exit(0);
-#else
-    exit(rc);
 #endif
+    return rc;
 }
 
 static bool handle_help_options(struct MPContext *mpctx)
@@ -507,21 +503,21 @@ int mpv_main(int argc, char *argv[])
                                            mpctx->global, argc, argv);
     if (r < 0) {
         if (r <= M_OPT_EXIT) {
-            exit_player(mpctx, EXIT_NONE);
+            return prepare_exit_cplayer(mpctx, EXIT_NONE);
         } else {
-            exit_player(mpctx, EXIT_ERROR);
+            return prepare_exit_cplayer(mpctx, EXIT_ERROR);
         }
     }
 
     mp_msg_update_msglevels(mpctx->global);
 
     if (handle_help_options(mpctx))
-        exit_player(mpctx, EXIT_NONE);
+        return prepare_exit_cplayer(mpctx, EXIT_NONE);
 
     if (!mpctx->playlist->first && !opts->player_idle_mode) {
         mp_print_version(mpctx->log, true);
         MP_INFO(mpctx, "%s", mp_help_text);
-        exit_player(mpctx, EXIT_NONE);
+        return prepare_exit_cplayer(mpctx, EXIT_NONE);
     }
 
 #ifdef _WIN32
@@ -530,9 +526,8 @@ int mpv_main(int argc, char *argv[])
 #endif
 
     if (mp_initialize(mpctx) < 0)
-        exit_player(mpctx, EXIT_ERROR);
+        return prepare_exit_cplayer(mpctx, EXIT_ERROR);
 
     mp_play_files(mpctx);
-    exit_player(mpctx, EXIT_NORMAL);
-    return 1;
+    return prepare_exit_cplayer(mpctx, EXIT_NORMAL);
 }