fix mdmon option parsing

running mdmon --takeover --all resulted in a segfault.

Also allow "--all" to be longer so that e.g. md_d127 can
successfully over-write it in the argument list visible
to 'ps'.

Signed-off-by: Luca Berra <bluca@comedia.it>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/mdmon.8 b/mdmon.8
index df9dfbcee7c0a172fd1b842d0414789230c80923..8a482b34070af03e3677c6e0afe4b472a8e353aa 100644 (file)
--- a/mdmon.8
+++ b/mdmon.8
@@ -157,6 +157,14 @@ This tells mdmon to find any active containers and start monitoring
 each of them if appropriate.  This is normally used with
 .B \-\-takeover
 late in the boot sequence.
+A separate
+.I mdmon
+process is started for each container as the
+.B \-\-all
+argument is over-written with the name of the container.  To allow for
+containers with names longer than 5 characters, this argument can be
+arbitrarily extended, e.g. to
+.BR \-\-all-active-arrays .
 
 .PP
 Note that
@@ -228,7 +236,7 @@ filesystem, like the root filesystem, should be remounted read-only.
 
 .SH EXAMPLES
 
-.B "  mdmon \-\-all \-\-takeover"
+.B "  mdmon \-\-all-active-arrays \-\-takeover"
 .br
 Any
 .I mdmon

diff --git a/mdmon.c b/mdmon.c
index 8e62a68b2319e1c3087c485d02aff03beaf516ba..a3da79543b877f2ecb224f6674127572916c85f9 100644 (file)
--- a/mdmon.c
+++ b/mdmon.c
@@ -247,7 +247,7 @@ static int do_fork(void)
 
 void usage(void)
 {
-       fprintf(stderr, "Usage: mdmon /device/name/for/container [target_dir]\n");
+       fprintf(stderr, "Usage: mdmon [--all] [--takeover] CONTAINER\n");
        exit(2);
 }
 
@@ -264,19 +264,23 @@ int main(int argc, char *argv[])
        int takeover = 0;
 
        for (arg = 1; arg < argc; arg++) {
-               if (strcmp(argv[arg], "--all") == 0 ||
-                   strcmp(argv[arg], "/proc/mdstat") == 0)
+               if (strncmp(argv[arg], "--all",5) == 0 ||
+                   strcmp(argv[arg], "/proc/mdstat") == 0) {
+                       container_name = argv[arg];
                        all = 1;
-               else if (strcmp(argv[arg], "--takeover") == 0)
+               } else if (strcmp(argv[arg], "--takeover") == 0)
                        takeover = 1;
                else if (container_name == NULL)
                        container_name = argv[arg];
                else
                        usage();
        }
+       if (container_name == NULL)
+               usage();
 
        if (all) {
                struct mdstat_ent *mdstat, *e;
+               int container_len = strlen(container_name);
 
                /* launch an mdmon instance for each container found */
                mdstat = mdstat_read(0, 0);
@@ -287,8 +291,8 @@ int main(int argc, char *argv[])
                                /* update cmdline so this mdmon instance can be
                                 * distinguished from others in a call to ps(1)
                                 */
-                               if (strlen(devname) <= strlen(container_name)) {
-                                       memset(container_name, 0, strlen(container_name));
+                               if (strlen(devname) <= container_len) {
+                                       memset(container_name, 0, container_len);
                                        sprintf(container_name, "%s", devname);
                                }
                                status |= mdmon(devname, e->devnum, 1,