git-branch: add options and tests for branch renaming
Extend git-branch with the following options:
git-branch -m|-M [<oldbranch>] newbranch
The -M variation is required to force renaming over an exsisting
branchname.
This also indroduces $GIT_DIR/RENAME_REF which is a "metabranch"
used when renaming branches. It will always hold the original sha1
for the latest renamed branch.
Additionally, if $GIT_DIR/logs/RENAME_REF exists, all branch rename
events are logged there.
Finally, some testcases are added to verify the new options.
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/refs.c b/refs.c
index 96ea8b6..cdedb45 100644
--- a/refs.c
+++ b/refs.c
@@ -610,6 +610,29 @@
return remove_empty_dir_recursive(path, len);
}
+static int is_refname_available(const char *ref, const char *oldref,
+ struct ref_list *list, int quiet)
+{
+ int namlen = strlen(ref); /* e.g. 'foo/bar' */
+ while (list) {
+ /* list->name could be 'foo' or 'foo/bar/baz' */
+ if (!oldref || strcmp(oldref, list->name)) {
+ int len = strlen(list->name);
+ int cmplen = (namlen < len) ? namlen : len;
+ const char *lead = (namlen < len) ? list->name : ref;
+ if (!strncmp(ref, list->name, cmplen) &&
+ lead[cmplen] == '/') {
+ if (!quiet)
+ error("'%s' exists; cannot create '%s'",
+ list->name, ref);
+ return 0;
+ }
+ }
+ list = list->next;
+ }
+ return 1;
+}
+
static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag)
{
char *ref_file;
@@ -643,29 +666,14 @@
orig_ref, strerror(errno));
goto error_return;
}
- if (is_null_sha1(lock->old_sha1)) {
- /* The ref did not exist and we are creating it.
- * Make sure there is no existing ref that is packed
- * whose name begins with our refname, nor a ref whose
- * name is a proper prefix of our refname.
- */
- int namlen = strlen(ref); /* e.g. 'foo/bar' */
- struct ref_list *list = get_packed_refs();
- while (list) {
- /* list->name could be 'foo' or 'foo/bar/baz' */
- int len = strlen(list->name);
- int cmplen = (namlen < len) ? namlen : len;
- const char *lead = (namlen < len) ? list->name : ref;
-
- if (!strncmp(ref, list->name, cmplen) &&
- lead[cmplen] == '/') {
- error("'%s' exists; cannot create '%s'",
- list->name, ref);
- goto error_return;
- }
- list = list->next;
- }
- }
+ /* When the ref did not exist and we are creating it,
+ * make sure there is no existing ref that is packed
+ * whose name begins with our refname, nor a ref whose
+ * name is a proper prefix of our refname.
+ */
+ if (is_null_sha1(lock->old_sha1) &&
+ !is_refname_available(ref, NULL, get_packed_refs(), 0))
+ goto error_return;
lock->lk = xcalloc(1, sizeof(struct lock_file));
@@ -776,6 +784,121 @@
return ret;
}
+int rename_ref(const char *oldref, const char *newref)
+{
+ static const char renamed_ref[] = "RENAMED-REF";
+ unsigned char sha1[20], orig_sha1[20];
+ int flag = 0, logmoved = 0;
+ struct ref_lock *lock;
+ char msg[PATH_MAX*2 + 100];
+ struct stat loginfo;
+ int log = !stat(git_path("logs/%s", oldref), &loginfo);
+
+ if (S_ISLNK(loginfo.st_mode))
+ return error("reflog for %s is a symlink", oldref);
+
+ if (!resolve_ref(oldref, orig_sha1, 1, &flag))
+ return error("refname %s not found", oldref);
+
+ if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
+ return 1;
+
+ if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
+ return 1;
+
+ if (snprintf(msg, sizeof(msg), "renamed %s to %s", oldref, newref) > sizeof(msg))
+ return error("Refnames to long");
+
+ lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL);
+ if (!lock)
+ return error("unable to lock %s", renamed_ref);
+ lock->force_write = 1;
+ if (write_ref_sha1(lock, orig_sha1, msg))
+ return error("unable to save current sha1 in %s", renamed_ref);
+
+ if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
+ return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
+ oldref, strerror(errno));
+
+ if (delete_ref(oldref, orig_sha1)) {
+ error("unable to delete old %s", oldref);
+ goto rollback;
+ }
+
+ if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
+ if (errno==EISDIR) {
+ if (remove_empty_directories(git_path("%s", newref))) {
+ error("Directory not empty: %s", newref);
+ goto rollback;
+ }
+ } else {
+ error("unable to delete existing %s", newref);
+ goto rollback;
+ }
+ }
+
+ if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
+ error("unable to create directory for %s", newref);
+ goto rollback;
+ }
+
+ retry:
+ if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
+ if (errno==EISDIR) {
+ if (remove_empty_directories(git_path("logs/%s", newref))) {
+ error("Directory not empty: logs/%s", newref);
+ goto rollback;
+ }
+ goto retry;
+ } else {
+ error("unable to move logfile tmp-renamed-log to logs/%s: %s",
+ newref, strerror(errno));
+ goto rollback;
+ }
+ }
+ logmoved = log;
+
+ lock = lock_ref_sha1_basic(newref, NULL, NULL);
+ if (!lock) {
+ error("unable to lock %s for update", newref);
+ goto rollback;
+ }
+
+ lock->force_write = 1;
+ hashcpy(lock->old_sha1, orig_sha1);
+ if (write_ref_sha1(lock, orig_sha1, msg)) {
+ error("unable to write current sha1 into %s", newref);
+ goto rollback;
+ }
+
+ return 0;
+
+ rollback:
+ lock = lock_ref_sha1_basic(oldref, NULL, NULL);
+ if (!lock) {
+ error("unable to lock %s for rollback", oldref);
+ goto rollbacklog;
+ }
+
+ lock->force_write = 1;
+ flag = log_all_ref_updates;
+ log_all_ref_updates = 0;
+ if (write_ref_sha1(lock, orig_sha1, NULL))
+ error("unable to write current sha1 into %s", oldref);
+ log_all_ref_updates = flag;
+
+ rollbacklog:
+ if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
+ error("unable to restore logfile %s from %s: %s",
+ oldref, newref, strerror(errno));
+ if (!logmoved && log &&
+ rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
+ error("unable to restore logfile %s from tmp-renamed-log: %s",
+ oldref, strerror(errno));
+
+ return 1;
+}
+
void unlock_ref(struct ref_lock *lock)
{
if (lock->lock_fd >= 0) {
