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>
This commit is contained in:
Lars Hjemli 2006-11-28 15:47:40 +01:00 committed by Junio C Hamano
parent 8ebe185bbf
commit c976d415e5
5 changed files with 250 additions and 26 deletions

View File

@ -8,8 +8,9 @@ git-branch - List, create, or delete branches.
SYNOPSIS
--------
[verse]
'git-branch' [-r] [-a] [-v] [--abbrev=<length>]
'git-branch' [-r | -a] [-v [--abbrev=<length>]]
'git-branch' [-l] [-f] <branchname> [<start-point>]
'git-branch' (-m | -M) [<oldbranch>] <newbranch>
'git-branch' (-d | -D) <branchname>...
DESCRIPTION
@ -24,6 +25,12 @@ It will start out with a head equal to the one given as <start-point>.
If no <start-point> is given, the branch will be created with a head
equal to that of the currently checked out branch.
With a '-m' or '-M' option, <oldbranch> will be renamed to <newbranch>.
If <oldbranch> had a corresponding reflog, it is renamed to match
<newbranch>, and a reflog entry is created to remember the branch
renaming. If <newbranch> exists, -M must be used to force the rename
to happen.
With a `-d` or `-D` option, `<branchname>` will be deleted. You may
specify more than one branch for deletion. If the branch currently
has a ref log then the ref log will also be deleted.
@ -46,6 +53,12 @@ OPTIONS
Force the creation of a new branch even if it means deleting
a branch that already exists with the same name.
-m::
Move/rename a branch and the corresponding reflog.
-M::
Move/rename a branch even if the new branchname already exists.
-r::
List the remote-tracking branches.
@ -53,7 +66,7 @@ OPTIONS
List both remote-tracking branches and local branches.
-v::
Show sha1 and subject message for each head.
Show sha1 and commit subjectline for each head.
--abbrev=<length>::
Alter minimum display length for sha1 in output listing,
@ -70,6 +83,12 @@ OPTIONS
be given as a branch name, a commit-id, or a tag. If this option
is omitted, the current branch is assumed.
<oldbranch>::
The name of an existing branch to rename.
<newbranch>::
The new name for an existing branch. The same restrictions as for
<branchname> applies.
Examples

View File

@ -11,7 +11,7 @@
#include "builtin.h"
static const char builtin_branch_usage[] =
"git-branch (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | [-r | -a] [-v] [--abbrev=<length>] ";
"git-branch (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | (-m | -M) [<oldbranch>] <newbranch> | [-r | -a] [-v [--abbrev=<length>]]";
static const char *head;
@ -245,9 +245,37 @@ static void create_branch(const char *name, const char *start,
die("Failed to write ref: %s.", strerror(errno));
}
static void rename_branch(const char *oldname, const char *newname, int force)
{
char oldref[PATH_MAX], newref[PATH_MAX];
unsigned char sha1[20];
if (snprintf(oldref, sizeof(oldref), "refs/heads/%s", oldname) > sizeof(oldref))
die("Old branchname too long");
if (check_ref_format(oldref))
die("Invalid branch name: %s", oldref);
if (snprintf(newref, sizeof(newref), "refs/heads/%s", newname) > sizeof(newref))
die("New branchname too long");
if (check_ref_format(newref))
die("Invalid branch name: %s", newref);
if (resolve_ref(newref, sha1, 1, NULL) && !force)
die("A branch named '%s' already exists.", newname);
if (rename_ref(oldref, newref))
die("Branch rename failed");
if (!strcmp(oldname, head) && create_symref("HEAD", newref))
die("Branch renamed to %s, but HEAD is not updated!", newname);
}
int cmd_branch(int argc, const char **argv, const char *prefix)
{
int delete = 0, force_delete = 0, force_create = 0;
int rename = 0, force_rename = 0;
int verbose = 0, abbrev = DEFAULT_ABBREV;
int reflog = 0;
int kinds = REF_LOCAL_BRANCH;
@ -277,6 +305,15 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
force_create = 1;
continue;
}
if (!strcmp(arg, "-m")) {
rename = 1;
continue;
}
if (!strcmp(arg, "-M")) {
rename = 1;
force_rename = 1;
continue;
}
if (!strcmp(arg, "-r")) {
kinds = REF_REMOTE_BRANCH;
continue;
@ -300,6 +337,10 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
usage(builtin_branch_usage);
}
if ((delete && rename) || (delete && force_create) ||
(rename && force_create))
usage(builtin_branch_usage);
head = xstrdup(resolve_ref("HEAD", head_sha1, 0, NULL));
if (!head)
die("Failed to resolve HEAD as a valid ref.");
@ -311,6 +352,10 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
delete_branches(argc - i, argv + i, force_delete);
else if (i == argc)
print_ref_list(kinds, verbose, abbrev);
else if (rename && (i == argc - 1))
rename_branch(head, argv[i], force_rename);
else if (rename && (i == argc - 2))
rename_branch(argv[i], argv[i + 1], force_rename);
else if (i == argc - 1)
create_branch(argv[i], head, force_create, reflog);
else if (i == argc - 2)

169
refs.c
View File

@ -610,6 +610,29 @@ static int remove_empty_directories(char *file)
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 @@ static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char
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 @@ int delete_ref(const char *refname, unsigned char *sha1)
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) {

3
refs.h
View File

@ -47,4 +47,7 @@ extern int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned
/** Returns 0 if target has the right format for a ref. **/
extern int check_ref_format(const char *target);
/** rename ref, return 0 on success **/
extern int rename_ref(const char *oldref, const char *newref);
#endif /* REFS_H */

View File

@ -70,4 +70,38 @@ test_expect_success \
git-branch -d l/m &&
git-branch l'
test_expect_success \
'git branch -m m m/m should work' \
'git-branch -l m &&
git-branch -m m m/m &&
test -f .git/logs/refs/heads/m/m'
test_expect_success \
'git branch -m n/n n should work' \
'git-branch -l n/n &&
git-branch -m n/n n
test -f .git/logs/refs/heads/n'
test_expect_failure \
'git branch -m o/o o should fail when o/p exists' \
'git-branch o/o &&
git-branch o/p &&
git-branch -m o/o o'
test_expect_failure \
'git branch -m q r/q should fail when r exists' \
'git-branch q &&
git-branch r &&
git-branch -m q r/q'
test_expect_success \
'git branch -m s/s s should work when s/t is deleted' \
'git-branch -l s/s &&
test -f .git/logs/refs/heads/s/s &&
git-branch -l s/t &&
test -f .git/logs/refs/heads/s/t &&
git-branch -d s/t &&
git-branch -m s/s s &&
test -f .git/logs/refs/heads/s'
test_done