Currently qemu_mallocz calls malloc and handling of zero by malloc is
implementation defined behaviour:
http://www.opengroup.org/onlinepubs/
7990989775/xsh/malloc.html
malloc(0) on AIX returns NULL[1] and qcow2 images without snapshots
are thus unusable
[1] Unless special Linux compatibility define is used when compiling
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6359
c046a42c-6fe2-441c-8c8c-
71466251a162
int64_t offset;
uint32_t extra_data_size;
+ if (!s->nb_snapshots) {
+ s->snapshots = NULL;
+ s->snapshots_size = 0;
+ return 0;
+ }
+
offset = s->snapshots_offset;
s->snapshots = qemu_mallocz(s->nb_snapshots * sizeof(QCowSnapshot));
if (!s->snapshots)
snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot));
if (!snapshots1)
goto fail;
- memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot));
- qemu_free(s->snapshots);
+ if (s->snapshots) {
+ memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot));
+ qemu_free(s->snapshots);
+ }
s->snapshots = snapshots1;
s->snapshots[s->nb_snapshots++] = *sn;