X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/0b4af330ced1003dcac7d169d0012ecf5c79e29f..0f9c48b1d23fbe958544094e97ba8ad2a7d8b8f4:/main.c

diff --git a/main.c b/main.c
index be8d0c2a..37c46183 100644
--- a/main.c
+++ b/main.c
@@ -23,8 +23,7 @@
 
 time_t starttime = 0;
 
-struct stats stats;
-
+extern struct stats stats;
 extern int verbose;
 
 static void show_malloc_stats(void);
@@ -231,7 +230,7 @@ static pid_t do_cmd(char *cmd,char *machine,char *user,char *path,int *f_in,int
 	if (local_server) {
 		if (read_batch)
 		    create_flist_from_batch(); /* sets batch_flist */
-		ret = local_child(argc, args, f_in, f_out);
+		ret = local_child(argc, args, f_in, f_out, child_main);
 	} else {
 		ret = piped_child(args,f_in,f_out);
 	}
@@ -493,6 +492,13 @@ static void do_server_recv(int f_in, int f_out, int argc,char *argv[])
 }
 
 
+int child_main(int argc, char *argv[])
+{
+	start_server(STDIN_FILENO, STDOUT_FILENO, argc, argv);
+	return 0;
+}
+
+
 void start_server(int f_in, int f_out, int argc, char *argv[])
 {
 	extern int cvs_exclude;
@@ -640,14 +646,14 @@ static int copy_argv (char *argv[])
 }
 
 
-/*
+/**
  * Start a client for either type of remote connection.  Work out
  * whether the arguments request a remote shell or rsyncd connection,
  * and call the appropriate connection function, then run_client.
  *
  * Calls either start_socket_client (for sockets) or do_cmd and
  * client_run (for ssh).
- */
+ **/
 static int start_client(int argc, char *argv[])
 {
 	char *p;
@@ -661,8 +667,6 @@ static int start_client(int argc, char *argv[])
 	extern int am_sender;
 	extern char *shell_cmd;
 	extern int rsync_port;
-	extern int whole_file;
-	extern int write_batch;
 	extern int read_batch;
 	int rc;
 
@@ -694,7 +698,7 @@ static int start_client(int argc, char *argv[])
 	    p = find_colon(argv[0]);
 
 	if (p) {
-		if (p[1] == ':') {
+		if (p[1] == ':') { /* double colon */
 			*p = 0;
 			return start_socket_client(argv[0], p+2, argc-1, argv+1);
 		}
@@ -716,12 +720,6 @@ static int start_client(int argc, char *argv[])
 		p = find_colon(argv[argc-1]);
 		if (!p) {
 			local_server = 1;
-			/*
-			 * disable "rsync algorithm" when both sides local,
-			 * except when creating a batch update
-			 */
-			if (!write_batch && whole_file == -1)
-				whole_file = 1;
 		} else if (p[1] == ':') {
 			*p = 0;
 			return start_socket_client(argv[argc-1], p+2, argc-1, argv);
@@ -786,22 +784,74 @@ static int start_client(int argc, char *argv[])
 }
 
 
-static RETSIGTYPE sigusr1_handler(int val) {
+static RETSIGTYPE sigusr1_handler(int UNUSED(val)) {
 	exit_cleanup(RERR_SIGNAL);
 }
 
-static RETSIGTYPE sigusr2_handler(int val) {
+static RETSIGTYPE sigusr2_handler(int UNUSED(val)) {
 	extern int log_got_error;
 	if (log_got_error) _exit(RERR_PARTIAL);
 	_exit(0);
 }
 
-static RETSIGTYPE sigchld_handler(int val) {
+static RETSIGTYPE sigchld_handler(int UNUSED(val)) {
 #ifdef WNOHANG
 	while (waitpid(-1, NULL, WNOHANG) > 0) ;
 #endif
 }
 
+
+/**
+ * This routine catches signals and tries to send them to gdb.
+ *
+ * Because it's called from inside a signal handler it ought not to
+ * use too many library routines.
+ *
+ * @todo Perhaps use "screen -X" instead/as well, to help people
+ * debugging without easy access to X.  Perhaps use an environment
+ * variable, or just call a script?
+ *
+ * @todo The /proc/ magic probably only works on Linux (and
+ * Solaris?)  Can we be more portable?
+ **/
+#ifdef MAINTAINER_MODE
+const char *get_panic_action(void)
+{
+	const char *cmd_fmt = getenv("RSYNC_PANIC_ACTION");
+
+	if (cmd_fmt)
+		return cmd_fmt;
+	else
+		return "xterm -display :0 -T Panic -n Panic "
+			"-e gdb /proc/%d/exe %d";
+}
+
+
+/**
+ * Handle a fatal signal by launching a debugger, controlled by $RSYNC_PANIC_ACTION.
+ *
+ * This signal handler is only installed if we were configured with
+ * --enable-maintainer-mode.  Perhaps it should always be on and we
+ * should just look at the environment variable, but I'm a bit leery
+ * of a signal sending us into a busy loop.
+ **/
+static RETSIGTYPE rsync_panic_handler(int UNUSED(whatsig))
+{
+	char cmd_buf[300];
+	int ret;
+
+	sprintf(cmd_buf, get_panic_action(),
+		getpid(), getpid());
+
+	/* Unless we failed to execute gdb, we allow the process to
+	 * continue.  I'm not sure if that's right. */
+	ret = system(cmd_buf);
+	if (ret)
+		_exit(ret);
+}
+#endif
+
+
 int main(int argc,char *argv[])
 {       
 	extern int am_root;
@@ -820,6 +870,12 @@ int main(int argc,char *argv[])
 	signal(SIGUSR1, sigusr1_handler);
 	signal(SIGUSR2, sigusr2_handler);
 	signal(SIGCHLD, sigchld_handler);
+#ifdef MAINTAINER_MODE
+	signal(SIGSEGV, rsync_panic_handler);
+	signal(SIGFPE, rsync_panic_handler);
+	signal(SIGABRT, rsync_panic_handler);
+	signal(SIGBUS, rsync_panic_handler);
+#endif /* def MAINTAINER_MODE */
 
 	starttime = time(NULL);
 	am_root = (getuid() == 0);
@@ -887,8 +943,10 @@ int main(int argc,char *argv[])
 
 	ret = start_client(argc, argv);
 	if (ret == -1) 
-	    exit_cleanup(RERR_STARTCLIENT);
+		exit_cleanup(RERR_STARTCLIENT);
 	else
-	    exit_cleanup(ret);
-	return ret;
+		exit_cleanup(ret);
+
+	exit(ret);
+	/* NOTREACHED */
 }