Add -T (startup timeout) switch to clvmd

WHATS_NEW

@@ -1,5 +1,6 @@
 Version 2.02.16 -
 ====================================
+  Add -T (startup timeout) switch to clvmd.
   Improve lvm_dump.sh robustness.
   Update lvm2create_initrd to support gentoo.
 

daemons/clvmd/clvmd.c

@@ -99,6 +99,7 @@ static int child_pipe[2];
 #define DFAIL_LOCAL_SOCK 2
 #define DFAIL_CLUSTER_IF 3
 #define DFAIL_MALLOC     4
+#define DFAIL_TIMEOUT    5
 #define SUCCESS          0
 
 /* Prototypes for code further down */
@@ -122,7 +123,7 @@ static int process_reply(struct clvm_header *msg, int msglen, char *csid);
 static int open_local_sock(void);
 static struct local_client *find_client(int clientid);
 static void main_loop(int local_sock, int cmd_timeout);
-static void be_daemon(void);
+static void be_daemon(int start_timeout);
 static int check_all_clvmds_running(struct local_client *client);
 static int local_rendezvous_callback(struct local_client *thisfd, char *buf,
 				     int len, char *csid,
@@ -146,6 +147,7 @@ static void usage(char *prog, FILE *file)
 	fprintf(file, "   -d       Don't fork, run in the foreground\n");
 	fprintf(file, "   -R       Tell all running clvmds in the cluster to reload their device cache\n");
 	fprintf(file, "   -t<secs> Command timeout (default 60 seconds)\n");
+	fprintf(file, "   -T<secs> Startup timeout (default none)\n");
 	fprintf(file, "\n");
 }
 
@@ -169,13 +171,14 @@ int main(int argc, char *argv[])
 	signed char opt;
 	int debug = 0;
 	int cmd_timeout = DEFAULT_CMD_TIMEOUT;
+	int start_timeout = 0;
 	sigset_t ss;
 	int using_gulm = 0;
 
 	/* Deal with command-line arguments */
 	opterr = 0;
 	optind = 0;
-	while ((opt = getopt(argc, argv, "?vVhdt:R")) != EOF) {
+	while ((opt = getopt(argc, argv, "?vVhdt:RT:")) != EOF) {
 		switch (opt) {
 		case 'h':
 			usage(argv[0], stdout);
@@ -200,6 +203,14 @@ int main(int argc, char *argv[])
 				exit(1);
 			}
 			break;
+		case 'T':
+			start_timeout = atoi(optarg);
+			if (start_timeout <= 0) {
+				fprintf(stderr, "startup timeout is invalid\n");
+				usage(argv[0], stderr);
+				exit(1);
+			}
+			break;
 
 		case 'V':
 		        printf("Cluster LVM daemon version: %s\n", LVM_VERSION);
@@ -214,7 +225,7 @@ int main(int argc, char *argv[])
 
 	/* Fork into the background (unless requested not to) */
 	if (!debug) {
-		be_daemon();
+		be_daemon(start_timeout);
 	}
 
 	DEBUGLOG("CLVMD started\n");
@@ -647,36 +658,23 @@ static void main_loop(int local_sock, int cmd_timeout)
 	close(local_sock);
 }
 
-/*
+static void wait_for_child(int c_pipe, int timeout)
- * Fork into the background and detach from our parent process.
- * In the interests of user-friendliness we wait for the daemon
- * to complete initialisation before returning its status
- * the the user.
- */
-static void be_daemon()
 {
-        pid_t pid;
 	int child_status;
-	int devnull = open("/dev/null", O_RDWR);
+	int sstat;
-	if (devnull == -1) {
+	fd_set fds;
-		perror("Can't open /dev/null");
+	struct timeval tv = {timeout, 0};
-		exit(3);
+
+	FD_ZERO(&fds);
+	FD_SET(c_pipe, &fds);
+
+	sstat = select(c_pipe+1, &fds, NULL, NULL, timeout? &tv: NULL);
+	if (sstat == 0) {
+		fprintf(stderr, "clvmd startup timed out\n");
+		exit(DFAIL_TIMEOUT);
 	}
-
+	if (sstat == 1) {
-	pipe(child_pipe);
+		if (read(c_pipe, &child_status, sizeof(child_status)) !=
-
-	switch (pid = fork()) {
-	case -1:
-		perror("clvmd: can't fork");
-		exit(2);
-
-	case 0:		/* Child */
-	        close(child_pipe[0]);
-		break;
-
-	default:       /* Parent */
-		close(child_pipe[1]);
-		if (read(child_pipe[0], &child_status, sizeof(child_status)) !=
 		    sizeof(child_status)) {
 
 			fprintf(stderr, "clvmd failed in initialisation\n");
@@ -707,6 +705,40 @@ static void be_daemon()
 			exit(child_status);
 		}
 	}
+	fprintf(stderr, "clvmd startup, select failed: %s\n", strerror(errno));
+	exit(DFAIL_INIT);
+}
+
+/*
+ * Fork into the background and detach from our parent process.
+ * In the interests of user-friendliness we wait for the daemon
+ * to complete initialisation before returning its status
+ * the the user.
+ */
+static void be_daemon(int timeout)
+{
+        pid_t pid;
+	int devnull = open("/dev/null", O_RDWR);
+	if (devnull == -1) {
+		perror("Can't open /dev/null");
+		exit(3);
+	}
+
+	pipe(child_pipe);
+
+	switch (pid = fork()) {
+	case -1:
+		perror("clvmd: can't fork");
+		exit(2);
+
+	case 0:		/* Child */
+	        close(child_pipe[0]);
+		break;
+
+	default:       /* Parent */
+		close(child_pipe[1]);
+		wait_for_child(child_pipe[0], timeout);
+	}
 
 	/* Detach ourself from the calling environment */
 	if (close(0) || close(1) || close(2)) {