Re: [libvirt] [PATCH v2 1/4] Add a read/write lock implementation

27 Jan 2014


      On 01/27/2014 10:18 AM, Daniel P. Berrange wrote:
...
Add virRWLock backed up by a POSIX rwlock primitive
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
...
+int virRWLockInit(virRWLockPtr m)
+{
+    if (pthread_rwlock_init(&m->lock, NULL) != 0) {
+        errno = EINVAL;
+        return -1;
My concern from v1 still stands - this blindly overwrites non-EINVAL
errors, and better would be:

int rc = pthread_rwlock_init(&m->lock, NULL);
if (rc) {
    errno = rc;
    return -1;
}
...
+void virRWLockDestroy(virRWLockPtr m)
+{
+    pthread_rwlock_destroy(&m->lock);
Likewise, it might be nice to add VIR_DEBUG messages when discarding a
non-zero result, as a way to diagnose the programmer errors that caused
that situation.

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org