X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=server.c;h=f19fc996ecc7355ddf24379e242fcec4da287dd6;hp=4f1d5708f76e997ff8fc5ee477dd97d65a6b3785;hb=e2167286448ce2ed9a01a548e7e9832563035088;hpb=17c140cc24838c2b7049e2b4c17621f4284d53dc

diff --git a/server.c b/server.c
index 4f1d5708..f19fc996 100644
--- a/server.c
+++ b/server.c
@@ -45,6 +45,7 @@
 #include "afh.h"
 #include "string.h"
 #include "afs.h"
+#include "net.h"
 #include "server.h"
 #include "list.h"
 #include "send.h"
@@ -52,7 +53,6 @@
 #include "vss.h"
 #include "config.h"
 #include "close_on_fork.h"
-#include "net.h"
 #include "daemon.h"
 #include "ipc.h"
 #include "fd.h"
@@ -100,12 +100,33 @@ uint32_t afs_socket_cookie;
 /** The mutex protecting the shared memory area containing the mmd struct. */
 int mmd_mutex;
 
+/* Serializes log output. */
+static int log_mutex;
+
 static struct sched sched;
 static struct signal_task *signal_task;
 
 /** The process id of the audio file selector process. */
 pid_t afs_pid = 0;
 
+/* The the main server process (parent of afs and the command handlers). */
+static pid_t server_pid;
+
+/**
+ * Tell whether the executing process is a command handler.
+ *
+ * Cleanup on exit must be performed differently for command handlers.
+ *
+ * \return True if the pid of the executing process is neither the server pid
+ * nor the afs pid.
+ */
+bool process_is_command_handler(void)
+{
+	pid_t pid = getpid();
+
+	return pid != afs_pid && pid != server_pid;
+}
+
 /** The task responsible for server command handling. */
 struct server_command_task {
 	/** TCP port on which para_server listens for connections. */
@@ -133,9 +154,17 @@ char *server_get_tasks(void)
 	return get_task_list(&sched);
 }
 
-/*
- * setup shared memory area and get mutex for locking
- */
+static void pre_log_hook(void)
+{
+	mutex_lock(log_mutex);
+}
+
+static void post_log_hook(void)
+{
+	mutex_unlock(log_mutex);
+}
+
+/* Setup shared memory area and init mutexes */
 static void init_ipc_or_die(void)
 {
 	void *shm;
@@ -154,6 +183,10 @@ static void init_ipc_or_die(void)
 	if (ret < 0)
 		goto err_out;
 	mmd_mutex = ret;
+	ret = mutex_new();
+	if (ret < 0)
+		goto destroy_mmd_mutex;
+	log_mutex = ret;
 
 	mmd->num_played = 0;
 	mmd->num_commands = 0;
@@ -163,6 +196,8 @@ static void init_ipc_or_die(void)
 	mmd->vss_status_flags = VSS_NEXT;
 	mmd->new_vss_status_flags = VSS_NEXT;
 	return;
+destroy_mmd_mutex:
+	mutex_destroy(mmd_mutex);
 err_out:
 	PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 	exit(EXIT_FAILURE);
@@ -248,7 +283,7 @@ success:
 		daemon_set_flag(DF_LOG_TIMING);
 	daemon_set_priority(OPT_UINT32_VAL(PRIORITY));
 	if (user_list_file)
-		init_user_list(user_list_file);
+		user_list_init(user_list_file);
 	ret = 1;
 free_cf:
 	free(cf);
@@ -307,27 +342,22 @@ static int signal_post_select(struct sched *s, __a_unused void *context)
 		PARA_EMERG_LOG("terminating on signal %d\n", signum);
 		kill(0, SIGTERM);
 		/*
-		 * We must wait for afs because afs catches SIGINT/SIGTERM.
-		 * Before reacting to the signal, afs might want to use the
+		 * We must wait for all of our children to die. For the afs
+		 * process or a command handler might want to use the
 		 * shared memory area and the mmd mutex.  If we destroy this
 		 * mutex too early and afs tries to lock the shared memory
 		 * area, the call to mutex_lock() will fail and terminate the
 		 * afs process. This leads to dirty osl tables.
-		 *
-		 * There's no such problem with the other children of the
-		 * server process (the command handlers) as these reset their
-		 * SIGINT/SIGTERM handlers to the default action, i.e.  these
-		 * processes get killed immediately by the above kill().
 		 */
-		PARA_INFO_LOG("waiting for afs (pid %d) to die\n",
-			(int)afs_pid);
-		waitpid(afs_pid, NULL, 0);
+		PARA_INFO_LOG("waiting for child processes to die\n");
+		mutex_unlock(mmd_mutex);
+		while (wait(NULL) != -1 || errno != ECHILD)
+			; /* still at least one child alive */
+		mutex_lock(mmd_mutex);
 cleanup:
 		free(mmd->afd.afhi.chunk_table);
-		close_listed_fds();
-		mutex_destroy(mmd_mutex);
-		shm_detach(mmd);
-		exit(EXIT_FAILURE);
+		task_notify_all(s, E_DEADLY_SIGNAL);
+		return -E_DEADLY_SIGNAL;
 	}
 	return 0;
 }
@@ -475,6 +505,8 @@ static int init_afs(int argc, char **argv)
 		int i;
 
 		afs_pid = getpid();
+		crypt_shutdown();
+		user_list_deplete();
 		for (i = argc - 1; i >= 0; i--)
 			memset(argv[i], 0, strlen(argv[i]));
 		i = argc - lls_num_inputs(cmdline_lpr) - 1;
@@ -532,10 +564,12 @@ static void server_init(int argc, char **argv, struct server_command_task *sct)
 	/* become daemon */
 	if (OPT_GIVEN(DAEMON))
 		daemon_pipe = daemonize(true /* parent waits for SIGTERM */);
-	init_random_seed_or_die();
+	server_pid = getpid();
+	crypt_init();
 	daemon_log_welcome("server");
-	init_ipc_or_die(); /* init mmd struct and mmd->lock */
+	init_ipc_or_die(); /* init mmd struct, mmd and log mutex */
 	daemon_set_start_time();
+	daemon_set_hooks(pre_log_hook, post_log_hook);
 	PARA_NOTICE_LOG("initializing audio format handlers\n");
 	afh_init();
 
@@ -610,6 +644,21 @@ static int server_select(int max_fileno, fd_set *readfds, fd_set *writefds,
 	return ret;
 }
 
+/**
+ * Deallocate all lopsub parse results.
+ *
+ * The server allocates a parse result for command line options and optionally
+ * a second parse result for the effective configuration, defined by merging
+ * the command line options with the options stored in the configuration file.
+ * This function frees both structures.
+ */
+void free_lpr(void)
+{
+	lls_free_parse_result(server_lpr, CMD_PTR);
+	if (server_lpr != cmdline_lpr)
+		lls_free_parse_result(cmdline_lpr, CMD_PTR);
+}
+
 /**
  * The main function of para_server.
  *
@@ -630,23 +679,29 @@ int main(int argc, char *argv[])
 	server_init(argc, argv, sct);
 	mutex_lock(mmd_mutex);
 	ret = schedule(&sched);
+	/*
+	 * We hold the mmd lock: it was re-acquired in server_select()
+	 * after the select call.
+	 */
+	mutex_unlock(mmd_mutex);
 	sched_shutdown(&sched);
+	crypt_shutdown();
 	signal_shutdown(signal_task);
-	if (sct->child_fd < 0) { /* parent (server) */
+	if (!process_is_command_handler()) { /* parent (server) */
+		mutex_destroy(mmd_mutex);
+		daemon_set_hooks(NULL, NULL); /* only one process remaining */
+		mutex_destroy(log_mutex);
+		deplete_close_on_fork_list();
 		if (ret < 0)
 			PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-	} else { /* child (command handler) */
-		/*
-		 * We hold the lock: it was re-acquired in server_select()
-		 * after the select call.
-		 */
-		mutex_unlock(mmd_mutex);
+	} else {
 		alarm(ALARM_TIMEOUT);
 		close_listed_fds();
 		ret = handle_connect(sct->child_fd);
 	}
-	lls_free_parse_result(server_lpr, CMD_PTR);
-	if (server_lpr != cmdline_lpr)
-		lls_free_parse_result(cmdline_lpr, CMD_PTR);
+	vss_shutdown();
+	shm_detach(mmd);
+	user_list_deplete();
+	free_lpr();
 	exit(ret < 0? EXIT_FAILURE : EXIT_SUCCESS);
 }