Re: [libvirt] [PATCH] nodeinfo: Make sure we always reset errno before calling readdir

10 Apr 2014

      On Thu, 10 Apr 2014 09:22:42 -0600
Eric Blake <eblake@redhat.com> wrote:
...
On 04/10/2014 08:38 AM, Natanael Copa wrote:
...
...
...
-    errno = 0;
-    while ((cpudirent = readdir(cpudir))) {
+    for (errno = 0; (cpudirent = readdir(cpudir)); errno = 0) {
         if (sscanf(cpudirent->d_name, "cpu%u", &cpu) != 1)
             continue;
...
I suppose we could use helper function to make it more readable:
static struct dirent *virReaddir(DIR *dirp)
{
    errno = 0;
    return readdir(dirp);
}
Or maybe:
int virReaddir(DIR *dirp, struct dirent **ent)
{
    errno = 0;
    *ent = readdir(dirp);
    if (!*ent && errno) {
        virReportSystemError(errno, _("unable to read directory"))
        return -1;
    }
    return *ent ? 1 : 0;
}
and used as:
while ((ret = virReaddir(dirp, &entry)) > 0) {
    process entry
}
if (ret < 0)
    goto error;
This looks better yes.

Should I prepare a new patch with this? And grep for more readdirs?

-nc