+static char *find_branch_name(struct rev_info *rev)
+{
+ int i, positive = -1;
+ unsigned char branch_sha1[20];
+ const unsigned char *tip_sha1;
+ const char *ref;
+ char *full_ref, *branch = NULL;
+
+ for (i = 0; i < rev->cmdline.nr; i++) {
+ if (rev->cmdline.rev[i].flags & UNINTERESTING)
+ continue;
+ if (positive < 0)
+ positive = i;
+ else
+ return NULL;
+ }
+ if (positive < 0)
+ return NULL;
+ ref = rev->cmdline.rev[positive].name;
+ tip_sha1 = rev->cmdline.rev[positive].item->sha1;
+ if (dwim_ref(ref, strlen(ref), branch_sha1, &full_ref) &&
+ !prefixcmp(full_ref, "refs/heads/") &&
+ !hashcmp(tip_sha1, branch_sha1))
+ branch = xstrdup(full_ref + strlen("refs/heads/"));
+ free(full_ref);
+ return branch;
+}
+