Re: [libvirt] [v2] storage: Ignore dangling symbol link for filesystem pool
于 2010年12月21日 00:09, Eric Blake 写道:
On 12/20/2010 12:14 AM, Osier Yang wrote:
> If there is a dangling symbol link in filesystem pool, the pool
s/symbol/symbolic/
> will be failed to start or refresh, this patch is to fix it by
s/will be failed/will fail/
> ignoring it with a warning log.
> @@ -986,6 +988,12 @@ virStorageBackendVolOpenCheckMode(const char *path, unsigned int
flags)
> struct stat sb;
>
> if ((fd = open(path, O_RDONLY|O_NONBLOCK|O_NOCTTY))< 0) {
> + if (areadlink(path)) {
> + VIR_WARN("cannot open volume '%s': %s", path,
> + strerror(errno));
> + return -2;
Memory leak - areadlink() returns a malloc()d string that the user must
free.Also, areadlink() is expensive (in addition to malloc(), it makes
several syscalls);
oh, just looked at the source code of areadlink, indeed, thanks.
a more efficient solution would be to check if errno
is ELOOP or ENOENT (the only possibilities for a dangling symlink;
any
other error should return -1), and in those two cases a successful
lstat() is sufficient to detect a broken symlink without resorting to
reading its contents.
I guess you mean stat, lstat will not work here, as it doesn't follow
the *symbolic* link. what we need to do is to determine if the symbolic
link is dangling, so use "stat" to update the patch, v3 send, thanks
again.
Regards
Osier