[sheepdog] [PATCH] new option -i to initialize storage directory

[Dietmar Maurer]

Each directory used by sheepdog must have a 'sheepdog_lock' file. Users can create that file running 'sheep -i /path/to/store'. The daemon will not start if that file is missing.

This prevent users from starting sheep on wrong directories, for example when mount with fstab fails on startup.

Signed-off-by: Dietmar Maurer <dietmar at proxmox.com>
---
 sheep/sheep.c      |   16 ++++++++++++++--
 sheep/sheep_priv.h |    1 +
 sheep/store.c      |    8 ++++----
 3 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/sheep/sheep.c b/sheep/sheep.c
index 2e208de..8922415 100644
--- a/sheep/sheep.c
+++ b/sheep/sheep.c
@@ -41,6 +41,7 @@ static struct option const long_options[] = {
 	{"foreground", no_argument, NULL, 'f'},
 	{"gateway", no_argument, NULL, 'g'},
 	{"help", no_argument, NULL, 'h'},
+	{"initialize", no_argument, NULL, 'i'},
 	{"loglevel", required_argument, NULL, 'l'},
 	{"myaddr", required_argument, NULL, 'y'},
 	{"stdout", no_argument, NULL, 'o'},
@@ -52,7 +53,7 @@ static struct option const long_options[] = {
 	{NULL, 0, NULL, 0},
 };
 
-static const char *short_options = "c:dDfghl:op:P:v:wy:z:";
+static const char *short_options = "c:dDfghil:op:P:v:wy:z:";
 
 static void usage(int status)
 {
@@ -70,6 +71,7 @@ Options:\n\
   -f, --foreground        make the program run in the foreground\n\
   -g, --gateway           make the progam run as a gateway mode (same as '-v 0')\n\
   -h, --help              display this help and exit\n\
+  -i, --initialize        initialize store\n\
   -l, --loglevel          specify the level of logging detail\n\
   -o, --stdout            log to stdout instead of shared logger\n\
   -p, --port              specify the TCP port on which to listen\n\
@@ -142,6 +144,7 @@ int main(int argc, char **argv)
 	struct cluster_driver *cdrv;
 	int enable_write_cache = 0; /* disabled by default */
 	char *pid_file = NULL;
+	int initialize = 0;
 
 	signal(SIGPIPE, SIG_IGN);
 
@@ -162,6 +165,9 @@ int main(int argc, char **argv)
 		case 'f':
 			is_daemon = 0;
 			break;
+		case 'i':
+			initialize = 1;
+			break;
 		case 'l':
 			log_level = strtol(optarg, &p, 10);
 			if (optarg == p || log_level < SDOG_EMERG ||
@@ -249,6 +255,12 @@ int main(int argc, char **argv)
 	if (optind != argc)
 		dir = argv[optind];
 
+	if (initialize) {
+		if (init_base_path(dir))
+			exit(1);
+		exit(0);
+	}
+
 	snprintf(path, sizeof(path), "%s/" LOG_FILE_NAME, dir);
 
 	srandom(port);
@@ -256,7 +268,7 @@ int main(int argc, char **argv)
 	if (is_daemon && daemon(0, 0))
 		exit(1);
 
-	ret = init_base_path(dir);
+	ret = lock_base_dir(dir, 0);
 	if (ret)
 		exit(1);
 
diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
index 116be97..d21f33f 100644
--- a/sheep/sheep_priv.h
+++ b/sheep/sheep_priv.h
@@ -189,6 +189,7 @@ static inline uint32_t sys_epoch(void)
 int create_listen_port(int port, void *data);
 
 int init_store(const char *dir, int enable_write_cache);
+int lock_base_dir(const char *d, int create);
 int init_base_path(const char *dir);
 
 int add_vdi(char *data, int data_len, uint64_t size, uint32_t *new_vid,
diff --git a/sheep/store.c b/sheep/store.c
index a05822d..e825379 100644
--- a/sheep/store.c
+++ b/sheep/store.c
@@ -261,9 +261,9 @@ again:
 	return 0;
 }
 
-#define LOCK_PATH "/lock"
+#define LOCK_PATH "/sheepdog_lock"
 
-static int lock_base_dir(const char *d)
+int lock_base_dir(const char *d, int create)
 {
 	char *lock_path;
 	int ret = 0;
@@ -272,7 +272,7 @@ static int lock_base_dir(const char *d)
 	lock_path = zalloc(strlen(d) + strlen(LOCK_PATH) + 1);
 	sprintf(lock_path, "%s" LOCK_PATH, d);
 
-	fd = open(lock_path, O_WRONLY|O_CREAT, def_fmode);
+	fd = open(lock_path, create ? O_WRONLY|O_CREAT : O_WRONLY, def_fmode);
 	if (fd < 0) {
 		eprintf("failed to open lock file %s (%s)\n",
 			lock_path, strerror(errno));
@@ -304,7 +304,7 @@ int init_base_path(const char *d)
 	ret = init_path(d, &new);
 	if (ret)
 		return ret;
-	return lock_base_dir(d);
+	return lock_base_dir(d, 1);
 }
 
 #define OBJ_PATH "/obj/"
-- 
1.7.2.5