struct lock_file *lk;
unsigned char old_sha1[20];
int lock_fd;
- int force_write;
};
/*
};
/*
- * Used as a flag to ref_transaction_delete when a loose ref is being
+ * Flag passed to lock_ref_sha1_basic() telling it to tolerate broken
+ * refs (i.e., because the reference is about to be deleted anyway).
+ */
+#define REF_DELETING 0x02
+
+/*
+ * Used as a flag in ref_update::flags when a loose ref is being
* pruned.
*/
-#define REF_ISPRUNING 0x0100
+#define REF_ISPRUNING 0x04
+
+/*
+ * Used as a flag in ref_update::flags when the reference should be
+ * updated to new_sha1.
+ */
+#define REF_HAVE_NEW 0x08
+
+/*
+ * Used as a flag in ref_update::flags when old_sha1 should be
+ * checked.
+ */
+#define REF_HAVE_OLD 0x10
+
/*
* Try to read one refname component from the front of refname.
* Return the length of the component found, or -1 if the component is
static struct ref_lock *lock_ref_sha1_basic(const char *refname,
const unsigned char *old_sha1,
const struct string_list *skip,
- int flags, int *type_p)
+ unsigned int flags, int *type_p)
{
char *ref_file;
const char *orig_refname = refname;
int type, lflags;
int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
int resolve_flags = 0;
- int missing = 0;
int attempts_remaining = 3;
lock = xcalloc(1, sizeof(struct ref_lock));
orig_refname, strerror(errno));
goto error_return;
}
- missing = is_null_sha1(lock->old_sha1);
- /* 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 the ref did not exist and we are creating it, make sure
+ * there is no existing packed ref whose name begins with our
+ * refname, nor a packed ref whose name is a proper prefix of
+ * our refname.
*/
- if (missing &&
+ if (is_null_sha1(lock->old_sha1) &&
!is_refname_available(refname, skip, get_packed_refs(&ref_cache))) {
last_errno = ENOTDIR;
goto error_return;
lock->ref_name = xstrdup(refname);
lock->orig_ref_name = xstrdup(orig_refname);
ref_file = git_path("%s", refname);
- if (missing)
- lock->force_write = 1;
- if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
- lock->force_write = 1;
retry:
switch (safe_create_leading_directories(ref_file)) {
transaction = ref_transaction_begin(&err);
if (!transaction ||
ref_transaction_delete(transaction, r->name, r->sha1,
- REF_ISPRUNING, 1, NULL, &err) ||
+ REF_ISPRUNING, NULL, &err) ||
ref_transaction_commit(transaction, &err)) {
ref_transaction_free(transaction);
error("%s", err.buf);
return 0;
}
-int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
+int delete_ref(const char *refname, const unsigned char *sha1, unsigned int flags)
{
struct ref_transaction *transaction;
struct strbuf err = STRBUF_INIT;
transaction = ref_transaction_begin(&err);
if (!transaction ||
- ref_transaction_delete(transaction, refname, sha1, delopt,
- sha1 && !is_null_sha1(sha1), NULL, &err) ||
+ ref_transaction_delete(transaction, refname,
+ (sha1 && !is_null_sha1(sha1)) ? sha1 : NULL,
+ flags, NULL, &err) ||
ref_transaction_commit(transaction, &err)) {
error("%s", err.buf);
ref_transaction_free(transaction);
error("unable to lock %s for update", newrefname);
goto rollback;
}
- lock->force_write = 1;
hashcpy(lock->old_sha1, orig_sha1);
if (write_ref_sha1(lock, orig_sha1, logmsg)) {
error("unable to write current sha1 into %s", newrefname);
goto rollbacklog;
}
- lock->force_write = 1;
flag = log_all_ref_updates;
log_all_ref_updates = 0;
if (write_ref_sha1(lock, orig_sha1, NULL))
static char term = '\n';
struct object *o;
- if (!lock) {
- errno = EINVAL;
- return -1;
- }
- if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
- unlock_ref(lock);
- return 0;
- }
o = parse_object(sha1);
if (!o) {
error("Trying to write ref %s with nonexistent object %s",
}
/**
- * Information needed for a single ref update. Set new_sha1 to the
- * new value or to zero to delete the ref. To check the old value
- * while locking the ref, set have_old to 1 and set old_sha1 to the
- * value or to zero to ensure the ref does not exist before update.
+ * Information needed for a single ref update. Set new_sha1 to the new
+ * value or to null_sha1 to delete the ref. To check the old value
+ * while the ref is locked, set (flags & REF_HAVE_OLD) and set
+ * old_sha1 to the old value, or to null_sha1 to ensure the ref does
+ * not exist before update.
*/
struct ref_update {
+ /*
+ * If (flags & REF_HAVE_NEW), set the reference to this value:
+ */
unsigned char new_sha1[20];
+ /*
+ * If (flags & REF_HAVE_OLD), check that the reference
+ * previously had this value:
+ */
unsigned char old_sha1[20];
- int flags; /* REF_NODEREF? */
- int have_old; /* 1 if old_sha1 is valid, 0 otherwise */
+ /*
+ * One or more of REF_HAVE_NEW, REF_HAVE_OLD, REF_NODEREF,
+ * REF_DELETING, and REF_ISPRUNING:
+ */
+ unsigned int flags;
struct ref_lock *lock;
int type;
char *msg;
const char *refname,
const unsigned char *new_sha1,
const unsigned char *old_sha1,
- int flags, int have_old, const char *msg,
+ unsigned int flags, const char *msg,
struct strbuf *err)
{
struct ref_update *update;
if (transaction->state != REF_TRANSACTION_OPEN)
die("BUG: update called for transaction that is not open");
- if (have_old && !old_sha1)
- die("BUG: have_old is true but old_sha1 is NULL");
-
- if (!is_null_sha1(new_sha1) &&
+ if (new_sha1 && !is_null_sha1(new_sha1) &&
check_refname_format(refname, REFNAME_ALLOW_ONELEVEL)) {
strbuf_addf(err, "refusing to update ref with bad name %s",
refname);
}
update = add_update(transaction, refname);
- hashcpy(update->new_sha1, new_sha1);
- update->flags = flags;
- update->have_old = have_old;
- if (have_old)
+ if (new_sha1) {
+ hashcpy(update->new_sha1, new_sha1);
+ flags |= REF_HAVE_NEW;
+ }
+ if (old_sha1) {
hashcpy(update->old_sha1, old_sha1);
+ flags |= REF_HAVE_OLD;
+ }
+ update->flags = flags;
if (msg)
update->msg = xstrdup(msg);
return 0;
int ref_transaction_create(struct ref_transaction *transaction,
const char *refname,
const unsigned char *new_sha1,
- int flags, const char *msg,
+ unsigned int flags, const char *msg,
struct strbuf *err)
{
+ if (!new_sha1 || is_null_sha1(new_sha1))
+ die("BUG: create called without valid new_sha1");
return ref_transaction_update(transaction, refname, new_sha1,
- null_sha1, flags, 1, msg, err);
+ null_sha1, flags, msg, err);
}
int ref_transaction_delete(struct ref_transaction *transaction,
const char *refname,
const unsigned char *old_sha1,
- int flags, int have_old, const char *msg,
+ unsigned int flags, const char *msg,
+ struct strbuf *err)
+{
+ if (old_sha1 && is_null_sha1(old_sha1))
+ die("BUG: delete called with old_sha1 set to zeros");
+ return ref_transaction_update(transaction, refname,
+ null_sha1, old_sha1,
+ flags, msg, err);
+}
+
+int ref_transaction_verify(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *old_sha1,
+ unsigned int flags,
struct strbuf *err)
{
- return ref_transaction_update(transaction, refname, null_sha1,
- old_sha1, flags, have_old, msg, err);
+ if (!old_sha1)
+ die("BUG: verify called with old_sha1 set to NULL");
+ return ref_transaction_update(transaction, refname,
+ NULL, old_sha1,
+ flags, NULL, err);
}
-int update_ref(const char *action, const char *refname,
- const unsigned char *sha1, const unsigned char *oldval,
- int flags, enum action_on_err onerr)
+int update_ref(const char *msg, const char *refname,
+ const unsigned char *new_sha1, const unsigned char *old_sha1,
+ unsigned int flags, enum action_on_err onerr)
{
struct ref_transaction *t;
struct strbuf err = STRBUF_INIT;
t = ref_transaction_begin(&err);
if (!t ||
- ref_transaction_update(t, refname, sha1, oldval, flags,
- !!oldval, action, &err) ||
+ ref_transaction_update(t, refname, new_sha1, old_sha1,
+ flags, msg, &err) ||
ref_transaction_commit(t, &err)) {
const char *str = "update_ref failed for ref '%s': %s";
/* Acquire all locks while verifying old values */
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
- int flags = update->flags;
+ unsigned int flags = update->flags;
- if (is_null_sha1(update->new_sha1))
+ if ((flags & REF_HAVE_NEW) && is_null_sha1(update->new_sha1))
flags |= REF_DELETING;
- update->lock = lock_ref_sha1_basic(update->refname,
- (update->have_old ?
- update->old_sha1 :
- NULL),
- NULL,
- flags,
- &update->type);
+ update->lock = lock_ref_sha1_basic(
+ update->refname,
+ ((update->flags & REF_HAVE_OLD) ?
+ update->old_sha1 : NULL),
+ NULL,
+ flags,
+ &update->type);
if (!update->lock) {
ret = (errno == ENOTDIR)
? TRANSACTION_NAME_CONFLICT
/* Perform updates first so live commits remain referenced */
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
+ int flags = update->flags;
+
+ if ((flags & REF_HAVE_NEW) && !is_null_sha1(update->new_sha1)) {
+ int overwriting_symref = ((update->type & REF_ISSYMREF) &&
+ (update->flags & REF_NODEREF));
- if (!is_null_sha1(update->new_sha1)) {
- if (write_ref_sha1(update->lock, update->new_sha1,
- update->msg)) {
+ if (!overwriting_symref
+ && !hashcmp(update->lock->old_sha1, update->new_sha1)) {
+ /*
+ * The reference already has the desired
+ * value, so we don't need to write it.
+ */
+ unlock_ref(update->lock);
+ update->lock = NULL;
+ } else if (write_ref_sha1(update->lock, update->new_sha1,
+ update->msg)) {
update->lock = NULL; /* freed by write_ref_sha1 */
strbuf_addf(err, "Cannot update the ref '%s'.",
update->refname);
ret = TRANSACTION_GENERIC_ERROR;
goto cleanup;
+ } else {
+ /* freed by write_ref_sha1(): */
+ update->lock = NULL;
}
- update->lock = NULL; /* freed by write_ref_sha1 */
}
}
/* Perform deletes now that updates are safely completed */
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
+ int flags = update->flags;
- if (update->lock) {
+ if ((flags & REF_HAVE_NEW) && is_null_sha1(update->new_sha1)) {
if (delete_ref_loose(update->lock, update->type, err)) {
ret = TRANSACTION_GENERIC_ERROR;
goto cleanup;
}
- if (!(update->flags & REF_ISPRUNING))
+ if (!(flags & REF_ISPRUNING))
string_list_append(&refs_to_delete,
update->lock->ref_name);
}
struct ref_lock *lock;
char *log_file;
int status = 0;
+ int type;
memset(&cb, 0, sizeof(cb));
cb.flags = flags;
* reference itself, plus we might need to update the
* reference if --updateref was specified:
*/
- lock = lock_ref_sha1_basic(refname, sha1, NULL, 0, NULL);
+ lock = lock_ref_sha1_basic(refname, sha1, NULL, 0, &type);
if (!lock)
return error("cannot lock ref '%s'", refname);
if (!reflog_exists(refname)) {
(*cleanup_fn)(cb.policy_cb);
if (!(flags & EXPIRE_REFLOGS_DRY_RUN)) {
+ /*
+ * It doesn't make sense to adjust a reference pointed
+ * to by a symbolic ref based on expiring entries in
+ * the symbolic reference's reflog. Nor can we update
+ * a reference if there are no remaining reflog
+ * entries.
+ */
+ int update = (flags & EXPIRE_REFLOGS_UPDATE_REF) &&
+ !(type & REF_ISSYMREF) &&
+ !is_null_sha1(cb.last_kept_sha1);
+
if (close_lock_file(&reflog_lock)) {
status |= error("couldn't write %s: %s", log_file,
strerror(errno));
- } else if ((flags & EXPIRE_REFLOGS_UPDATE_REF) &&
+ } else if (update &&
(write_in_full(lock->lock_fd,
sha1_to_hex(cb.last_kept_sha1), 40) != 40 ||
write_str_in_full(lock->lock_fd, "\n") != 1 ||
} else if (commit_lock_file(&reflog_lock)) {
status |= error("unable to commit reflog '%s' (%s)",
log_file, strerror(errno));
- } else if ((flags & EXPIRE_REFLOGS_UPDATE_REF) && commit_ref(lock)) {
+ } else if (update && commit_ref(lock)) {
status |= error("couldn't set %s", lock->ref_name);
}
}