0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 4
};
+/*
+ * Used as a flag to ref_transaction_delete when a loose ref is being
+ * pruned.
+ */
+#define REF_ISPRUNING 0x0100
/*
* Try to read one refname component from the front of refname.
* Return the length of the component found, or -1 if the component is
prime_ref_dir(get_ref_dir(entry));
}
}
-/*
- * Return true iff refname1 and refname2 conflict with each other.
- * Two reference names conflict if one of them exactly matches the
- * leading components of the other; e.g., "foo/bar" conflicts with
- * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
- * "foo/barbados".
- */
-static int names_conflict(const char *refname1, const char *refname2)
+
+static int entry_matches(struct ref_entry *entry, const char *refname)
{
- for (; *refname1 && *refname1 == *refname2; refname1++, refname2++)
- ;
- return (*refname1 == '\0' && *refname2 == '/')
- || (*refname1 == '/' && *refname2 == '\0');
+ return refname && !strcmp(entry->name, refname);
}
-struct name_conflict_cb {
- const char *refname;
- const char *oldrefname;
- const char *conflicting_refname;
+struct nonmatching_ref_data {
+ const char *skip;
+ struct ref_entry *found;
};
-static int name_conflict_fn(struct ref_entry *entry, void *cb_data)
+static int nonmatching_ref_fn(struct ref_entry *entry, void *vdata)
{
- struct name_conflict_cb *data = (struct name_conflict_cb *)cb_data;
- if (data->oldrefname && !strcmp(data->oldrefname, entry->name))
+ struct nonmatching_ref_data *data = vdata;
+
+ if (entry_matches(entry, data->skip))
return 0;
- if (names_conflict(data->refname, entry->name)) {
- data->conflicting_refname = entry->name;
- return 1;
- }
- return 0;
+
+ data->found = entry;
+ return 1;
+}
+
+static void report_refname_conflict(struct ref_entry *entry,
+ const char *refname)
+{
+ error("'%s' exists; cannot create '%s'", entry->name, refname);
}
/*
* oldrefname is non-NULL, ignore potential conflicts with oldrefname
* (e.g., because oldrefname is scheduled for deletion in the same
* operation).
+ *
+ * Two reference names conflict if one of them exactly matches the
+ * leading components of the other; e.g., "foo/bar" conflicts with
+ * both "foo" and with "foo/bar/baz" but not with "foo/bar" or
+ * "foo/barbados".
*/
static int is_refname_available(const char *refname, const char *oldrefname,
struct ref_dir *dir)
{
- struct name_conflict_cb data;
- data.refname = refname;
- data.oldrefname = oldrefname;
- data.conflicting_refname = NULL;
+ const char *slash;
+ size_t len;
+ int pos;
+ char *dirname;
- sort_ref_dir(dir);
- if (do_for_each_entry_in_dir(dir, 0, name_conflict_fn, &data)) {
- error("'%s' exists; cannot create '%s'",
- data.conflicting_refname, refname);
+ for (slash = strchr(refname, '/'); slash; slash = strchr(slash + 1, '/')) {
+ /*
+ * We are still at a leading dir of the refname; we are
+ * looking for a conflict with a leaf entry.
+ *
+ * If we find one, we still must make sure it is
+ * not "oldrefname".
+ */
+ pos = search_ref_dir(dir, refname, slash - refname);
+ if (pos >= 0) {
+ struct ref_entry *entry = dir->entries[pos];
+ if (entry_matches(entry, oldrefname))
+ return 1;
+ report_refname_conflict(entry, refname);
+ return 0;
+ }
+
+
+ /*
+ * Otherwise, we can try to continue our search with
+ * the next component; if we come up empty, we know
+ * there is nothing under this whole prefix.
+ */
+ pos = search_ref_dir(dir, refname, slash + 1 - refname);
+ if (pos < 0)
+ return 1;
+
+ dir = get_ref_dir(dir->entries[pos]);
+ }
+
+ /*
+ * We are at the leaf of our refname; we want to
+ * make sure there are no directories which match it.
+ */
+ len = strlen(refname);
+ dirname = xmallocz(len + 1);
+ sprintf(dirname, "%s/", refname);
+ pos = search_ref_dir(dir, dirname, len + 1);
+ free(dirname);
+
+ if (pos >= 0) {
+ /*
+ * We found a directory named "refname". It is a
+ * problem iff it contains any ref that is not
+ * "oldrefname".
+ */
+ struct ref_entry *entry = dir->entries[pos];
+ struct ref_dir *dir = get_ref_dir(entry);
+ struct nonmatching_ref_data data;
+
+ data.skip = oldrefname;
+ sort_ref_dir(dir);
+ if (!do_for_each_entry_in_dir(dir, 0, nonmatching_ref_fn, &data))
+ return 1;
+
+ report_refname_conflict(data.found, refname);
return 0;
}
+
+ /*
+ * There is no point in searching for another leaf
+ * node which matches it; such an entry would be the
+ * ref we are looking for, not a conflict.
+ */
return 1;
}
return logs_found;
}
-/* This function should make sure errno is meaningful on error */
+/*
+ * Locks a "refs/" ref returning the lock on success and NULL on failure.
+ * On failure errno is set to something meaningful.
+ */
static struct ref_lock *lock_ref_sha1_basic(const char *refname,
const unsigned char *old_sha1,
int flags, int *type_p)
return NULL;
}
-struct ref_lock *lock_ref_sha1(const char *refname, const unsigned char *old_sha1)
-{
- char refpath[PATH_MAX];
- if (check_refname_format(refname, 0))
- return NULL;
- strcpy(refpath, mkpath("refs/%s", refname));
- return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
-}
-
struct ref_lock *lock_any_ref_for_update(const char *refname,
const unsigned char *old_sha1,
int flags, int *type_p)
* Write an entry to the packed-refs file for the specified refname.
* If peeled is non-NULL, write it as the entry's peeled value.
*/
-static void write_packed_entry(int fd, char *refname, unsigned char *sha1,
+static void write_packed_entry(FILE *fh, char *refname, unsigned char *sha1,
unsigned char *peeled)
{
- char line[PATH_MAX + 100];
- int len;
-
- len = snprintf(line, sizeof(line), "%s %s\n",
- sha1_to_hex(sha1), refname);
- /* this should not happen but just being defensive */
- if (len > sizeof(line))
- die("too long a refname '%s'", refname);
- write_or_die(fd, line, len);
-
- if (peeled) {
- if (snprintf(line, sizeof(line), "^%s\n",
- sha1_to_hex(peeled)) != PEELED_LINE_LENGTH)
- die("internal error");
- write_or_die(fd, line, PEELED_LINE_LENGTH);
- }
+ fprintf_or_die(fh, "%s %s\n", sha1_to_hex(sha1), refname);
+ if (peeled)
+ fprintf_or_die(fh, "^%s\n", sha1_to_hex(peeled));
}
/*
*/
static int write_packed_entry_fn(struct ref_entry *entry, void *cb_data)
{
- int *fd = cb_data;
enum peel_status peel_status = peel_entry(entry, 0);
if (peel_status != PEEL_PEELED && peel_status != PEEL_NON_TAG)
error("internal error: %s is not a valid packed reference!",
entry->name);
- write_packed_entry(*fd, entry->name, entry->u.value.sha1,
+ write_packed_entry(cb_data, entry->name, entry->u.value.sha1,
peel_status == PEEL_PEELED ?
entry->u.value.peeled : NULL);
return 0;
get_packed_ref_cache(&ref_cache);
int error = 0;
int save_errno = 0;
+ FILE *out;
if (!packed_ref_cache->lock)
die("internal error: packed-refs not locked");
- write_or_die(packed_ref_cache->lock->fd,
- PACKED_REFS_HEADER, strlen(PACKED_REFS_HEADER));
+ out = fdopen(packed_ref_cache->lock->fd, "w");
+ if (!out)
+ die_errno("unable to fdopen packed-refs descriptor");
+
+ fprintf_or_die(out, "%s", PACKED_REFS_HEADER);
do_for_each_entry_in_dir(get_packed_ref_dir(packed_ref_cache),
- 0, write_packed_entry_fn,
- &packed_ref_cache->lock->fd);
+ 0, write_packed_entry_fn, out);
+ if (fclose(out))
+ die_errno("write error");
+ packed_ref_cache->lock->fd = -1;
+
if (commit_lock_file(packed_ref_cache->lock)) {
save_errno = errno;
error = -1;
/* make sure nobody touched the ref, and unlink */
static void prune_ref(struct ref_to_prune *r)
{
- struct ref_lock *lock = lock_ref_sha1(r->name + 5, r->sha1);
+ struct ref_transaction *transaction;
+ struct strbuf err = STRBUF_INIT;
- if (lock) {
- unlink_or_warn(git_path("%s", r->name));
- unlock_ref(lock);
- try_remove_empty_parents(r->name);
+ if (check_refname_format(r->name, 0))
+ return;
+
+ transaction = ref_transaction_begin(&err);
+ if (!transaction ||
+ ref_transaction_delete(transaction, r->name, r->sha1,
+ REF_ISPRUNING, 1, &err) ||
+ ref_transaction_commit(transaction, NULL, &err)) {
+ ref_transaction_free(transaction);
+ error("%s", err.buf);
+ strbuf_release(&err);
+ return;
}
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
+ try_remove_empty_parents(r->name);
}
static void prune_refs(struct ref_to_prune *r)
return ret;
}
-static int repack_without_ref(const char *refname)
-{
- return repack_without_refs(&refname, 1, NULL);
-}
-
static int delete_ref_loose(struct ref_lock *lock, int flag)
{
if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
{
- struct ref_lock *lock;
- int ret = 0, flag = 0;
-
- lock = lock_ref_sha1_basic(refname, sha1, delopt, &flag);
- if (!lock)
+ 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), &err) ||
+ ref_transaction_commit(transaction, NULL, &err)) {
+ error("%s", err.buf);
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
return 1;
- ret |= delete_ref_loose(lock, flag);
-
- /* removing the loose one could have resurrected an earlier
- * packed one. Also, if it was not loose we need to repack
- * without it.
- */
- ret |= repack_without_ref(lock->ref_name);
-
- unlink_or_warn(git_path("logs/%s", lock->ref_name));
- clear_loose_ref_cache(&ref_cache);
- unlock_ref(lock);
- return ret;
+ }
+ ref_transaction_free(transaction);
+ strbuf_release(&err);
+ return 0;
}
/*
return retval;
}
-static struct ref_lock *update_ref_lock(const char *refname,
- const unsigned char *oldval,
- int flags, int *type_p,
- enum action_on_err onerr)
-{
- struct ref_lock *lock;
- lock = lock_any_ref_for_update(refname, oldval, flags, type_p);
- if (!lock) {
- const char *str = "Cannot lock the ref '%s'.";
- switch (onerr) {
- case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;
- case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;
- case UPDATE_REFS_QUIET_ON_ERR: break;
- }
- }
- return lock;
-}
-
-static int update_ref_write(const char *action, const char *refname,
- const unsigned char *sha1, struct ref_lock *lock,
- struct strbuf *err, enum action_on_err onerr)
-{
- if (write_ref_sha1(lock, sha1, action) < 0) {
- const char *str = "Cannot update the ref '%s'.";
- if (err)
- strbuf_addf(err, str, refname);
-
- switch (onerr) {
- case UPDATE_REFS_MSG_ON_ERR: error(str, refname); break;
- case UPDATE_REFS_DIE_ON_ERR: die(str, refname); break;
- case UPDATE_REFS_QUIET_ON_ERR: break;
- }
- return 1;
- }
- return 0;
-}
-
/**
* 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
const char refname[FLEX_ARRAY];
};
+/*
+ * Transaction states.
+ * OPEN: The transaction is in a valid state and can accept new updates.
+ * An OPEN transaction can be committed.
+ * CLOSED: A closed transaction is no longer active and no other operations
+ * than free can be used on it in this state.
+ * A transaction can either become closed by successfully committing
+ * an active transaction or if there is a failure while building
+ * the transaction thus rendering it failed/inactive.
+ */
+enum ref_transaction_state {
+ REF_TRANSACTION_OPEN = 0,
+ REF_TRANSACTION_CLOSED = 1
+};
+
/*
* Data structure for holding a reference transaction, which can
* consist of checks and updates to multiple references, carried out
struct ref_update **updates;
size_t alloc;
size_t nr;
+ enum ref_transaction_state state;
};
-struct ref_transaction *ref_transaction_begin(void)
+struct ref_transaction *ref_transaction_begin(struct strbuf *err)
{
return xcalloc(1, sizeof(struct ref_transaction));
}
{
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");
return 0;
}
-void ref_transaction_create(struct ref_transaction *transaction,
- const char *refname,
- const unsigned char *new_sha1,
- int flags)
+int ref_transaction_create(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *new_sha1,
+ int flags,
+ struct strbuf *err)
{
- struct ref_update *update = add_update(transaction, refname);
+ struct ref_update *update;
+
+ if (transaction->state != REF_TRANSACTION_OPEN)
+ die("BUG: create called for transaction that is not open");
+
+ if (!new_sha1 || is_null_sha1(new_sha1))
+ die("BUG: create ref with null new_sha1");
+
+ update = add_update(transaction, refname);
- assert(!is_null_sha1(new_sha1));
hashcpy(update->new_sha1, new_sha1);
hashclr(update->old_sha1);
update->flags = flags;
update->have_old = 1;
+ return 0;
}
-void ref_transaction_delete(struct ref_transaction *transaction,
- const char *refname,
- const unsigned char *old_sha1,
- int flags, int have_old)
+int ref_transaction_delete(struct ref_transaction *transaction,
+ const char *refname,
+ const unsigned char *old_sha1,
+ int flags, int have_old,
+ struct strbuf *err)
{
- struct ref_update *update = add_update(transaction, refname);
+ struct ref_update *update;
+
+ if (transaction->state != REF_TRANSACTION_OPEN)
+ die("BUG: delete called for transaction that is not open");
+
+ if (have_old && !old_sha1)
+ die("BUG: have_old is true but old_sha1 is NULL");
+ update = add_update(transaction, refname);
update->flags = flags;
update->have_old = have_old;
if (have_old) {
assert(!is_null_sha1(old_sha1));
hashcpy(update->old_sha1, old_sha1);
}
+ return 0;
}
int update_ref(const char *action, const char *refname,
const unsigned char *sha1, const unsigned char *oldval,
int flags, enum action_on_err onerr)
{
- struct ref_lock *lock;
- lock = update_ref_lock(refname, oldval, flags, NULL, onerr);
- if (!lock)
+ 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, &err) ||
+ ref_transaction_commit(t, action, &err)) {
+ const char *str = "update_ref failed for ref '%s': %s";
+
+ ref_transaction_free(t);
+ switch (onerr) {
+ case UPDATE_REFS_MSG_ON_ERR:
+ error(str, refname, err.buf);
+ break;
+ case UPDATE_REFS_DIE_ON_ERR:
+ die(str, refname, err.buf);
+ break;
+ case UPDATE_REFS_QUIET_ON_ERR:
+ break;
+ }
+ strbuf_release(&err);
return 1;
- return update_ref_write(action, refname, sha1, lock, NULL, onerr);
+ }
+ strbuf_release(&err);
+ ref_transaction_free(t);
+ return 0;
}
static int ref_update_compare(const void *r1, const void *r2)
int n = transaction->nr;
struct ref_update **updates = transaction->updates;
- if (!n)
+ if (transaction->state != REF_TRANSACTION_OPEN)
+ die("BUG: commit called for transaction that is not open");
+
+ if (!n) {
+ transaction->state = REF_TRANSACTION_CLOSED;
return 0;
+ }
/* Allocate work space */
delnames = xmalloc(sizeof(*delnames) * n);
for (i = 0; i < n; i++) {
struct ref_update *update = updates[i];
- update->lock = update_ref_lock(update->refname,
- (update->have_old ?
- update->old_sha1 : NULL),
- update->flags,
- &update->type,
- UPDATE_REFS_QUIET_ON_ERR);
+ update->lock = lock_any_ref_for_update(update->refname,
+ (update->have_old ?
+ update->old_sha1 :
+ NULL),
+ update->flags,
+ &update->type);
if (!update->lock) {
if (err)
strbuf_addf(err, "Cannot lock the ref '%s'.",
struct ref_update *update = updates[i];
if (!is_null_sha1(update->new_sha1)) {
- ret = update_ref_write(msg,
- update->refname,
- update->new_sha1,
- update->lock, err,
- UPDATE_REFS_QUIET_ON_ERR);
- update->lock = NULL; /* freed by update_ref_write */
- if (ret)
+ ret = write_ref_sha1(update->lock, update->new_sha1,
+ msg);
+ update->lock = NULL; /* freed by write_ref_sha1 */
+ if (ret) {
+ if (err)
+ strbuf_addf(err, "Cannot update the ref '%s'.",
+ update->refname);
goto cleanup;
+ }
}
}
struct ref_update *update = updates[i];
if (update->lock) {
- delnames[delnum++] = update->lock->ref_name;
ret |= delete_ref_loose(update->lock, update->type);
+ if (!(update->flags & REF_ISPRUNING))
+ delnames[delnum++] = update->lock->ref_name;
}
}
clear_loose_ref_cache(&ref_cache);
cleanup:
+ transaction->state = REF_TRANSACTION_CLOSED;
+
for (i = 0; i < n; i++)
if (updates[i]->lock)
unlock_ref(updates[i]->lock);