Fix deamon mode on macos

Author: CamilleScholtz

meson.build

@@ -437,6 +437,12 @@ if is_windows
   ]
 endif
 
+if is_darwin
+  sources += [
+    'src/apple/AppleMain.cxx',
+  ]
+endif
+
 if not is_android
   sources += [
     'src/CommandLine.cxx',

src/Main.cxx

@@ -677,6 +677,8 @@ try {
 
 #ifdef _WIN32
 	return win32_main(argc, argv);
+#elif __APPLE__
+	return apple_main(argc, argv);
 #else
 	return mpd_main(argc, argv);
 #endif

src/Main.hxx

@@ -61,4 +61,16 @@ win32_app_stopping();
 
 #endif
 
+#ifdef __APPLE__
+
+/**
+ * If program is run as deamon on macos, fork very early to avoid objc runtime issues,
+ * and then calls mpd_main() with specified arguments.
+ * If program is run as a regular application calls mpd_main() immediately.
+ */
+int
+apple_main(int argc, char *argv[]);
+
+#endif
+
 #endif

src/apple/AppleMain.cxx

@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright The Music Player Daemon Project
+
+#include "Main.hxx"
+#include "Instance.hxx"
+#include "CommandLine.hxx"
+#include "net/Init.hxx"
+#include "config/Data.hxx"
+
+static int service_argc;
+static char **service_argv;
+
+int apple_main(int argc, char *argv[])
+{
+	service_argc = argc;
+	service_argv = argv;
+
+#ifdef ENABLE_DAEMON
+	CommandLineOptions options;
+	ConfigData raw_config;
+
+	ParseCommandLine(argc, argv, options, raw_config);
+
+	if (options.daemon) {
+		// Fork before any Objective-C runtime initializations
+		pid_t pid = fork();
+		if (pid < 0)
+			throw MakeErrno("fork() failed");
+
+		if (pid > 0) {
+			// Parent process: exit immediately
+			_exit(0);
+		}
+	}
+#endif
+
+	return mpd_main(argc, argv);
+}

src/unix/Daemon.cxx

@@ -134,6 +134,8 @@ daemonize_begin(bool detach)
 
 	/* move to a child process */
 
+#ifndef __APPLE__
+
 	pid_t pid = fork();
 	if (pid < 0)
 		throw MakeErrno("fork() failed");
@@ -178,6 +180,8 @@ daemonize_begin(bool detach)
 			       WCOREDUMP(status) ? " (core dumped)" : "");
 
 	std::exit(WEXITSTATUS(status));
+
+#endif
 }
 
 void