path: root/branch.h
diff options
authorConrad Irwin <>2011-08-20 21:49:48 (GMT)
committerJunio C Hamano <>2011-08-22 23:00:36 (GMT)
commit55c4a673070f40f2ef12d0be269e95f1df6825a9 (patch)
treef3167659326c1308f6dfe3600ec0b57200cef335 /branch.h
parent1be9d84b2ed18c2b2e2d6a459d2b6d48d5ab86e5 (diff)
Prevent force-updating of the current branch
"git branch -M <foo> <current-branch>" allows updating the current branch which HEAD points, without the necessary house-keeping that git reset normally does to make this operation sensible. It also leaves the reflog in a confusing state (you would be warned when trying to read it). "git checkout -B <current branch> <foo>" is also partly vulnerable to this bug; due to inconsistent pre-flight checks it would perform half of its task and then abort just before rewriting the branch. Again this manifested itself as the index file getting out-of-sync with HEAD. "git branch -f" already guarded against this problem, and aborts with a fatal error. Update "git branch -M", "git checkout -B" and "git branch -f" to share the same check before allowing a branch to be created. These prevent you from updating the current branch. We considered suggesting the use of "git reset" in the failure message but concluded that it was not possible to discern what the user was actually trying to do. Signed-off-by: Conrad Irwin <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'branch.h')
1 files changed, 8 insertions, 0 deletions
diff --git a/branch.h b/branch.h
index 4026e38..01544e2 100644
--- a/branch.h
+++ b/branch.h
@@ -16,6 +16,14 @@ void create_branch(const char *head, const char *name, const char *start_name,
int force, int reflog, enum branch_track track);
+ * Validates that the requested branch may be created, returning the
+ * interpreted ref in ref, force indicates whether (non-head) branches
+ * may be overwritten. A non-zero return value indicates that the force
+ * parameter was non-zero and the branch already exists.
+ */
+int validate_new_branchname(const char *name, struct strbuf *ref, int force);
* Remove information about the state of working on the current
* branch. (E.g., MERGE_HEAD)