/*
a write style traverse - needs to get the transaction lock to
prevent deadlocks
WARNING: The data buffer given to the callback fn does NOT meet the
alignment guarantees malloc gives you.
*/
_PUBLIC_ int tdb_traverse(struct tdb_context *tdb,
tdb_traverse_func fn, void *private_data)
{
struct tdb_traverse_lock tl = { NULL, 0, 0, F_WRLCK };
enum tdb_lock_flags lock_flags;
int ret;
if (tdb->read_only || tdb->traverse_read) {
return tdb_traverse_read(tdb, fn, private_data);
}
lock_flags = TDB_LOCK_WAIT;
if (tdb->allrecord_lock.count != 0) {
/*
* This avoids a deadlock between tdb_lockall() and
* tdb_traverse(). See
* https://bugzilla.samba.org/show_bug.cgi?id=11381
*/
lock_flags = TDB_LOCK_NOWAIT;
}
if (tdb_transaction_lock(tdb, F_WRLCK, lock_flags)) {
return -1;
}
tdb->traverse_write++;
tdb_trace(tdb, "tdb_traverse_start");
ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
tdb->traverse_write--;
tdb_transaction_unlock(tdb, F_WRLCK);
return ret;
}
/*
a read style traverse - temporarily marks each record read only
*/
_PUBLIC_ int tdb_traverse_read(struct tdb_context *tdb,
tdb_traverse_func fn, void *private_data)
{
struct tdb_traverse_lock tl = { NULL, 0, 0, F_RDLCK };
int ret;
tdb->traverse_read++;
tdb_trace(tdb, "tdb_traverse_read_start");
ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
tdb->traverse_read--;
return ret;
}
/*
a read style traverse - temporarily marks the db read only
*/
_PUBLIC_ int tdb_traverse_read(struct tdb_context *tdb,
tdb_traverse_func fn, void *private_data)
{
struct tdb_traverse_lock tl = { NULL, 0, 0, F_RDLCK };
int ret;
/* we need to get a read lock on the transaction lock here to
cope with the lock ordering semantics of solaris10 */
if (tdb_transaction_lock(tdb, F_RDLCK, TDB_LOCK_WAIT)) {
return -1;
}
tdb->traverse_read++;
tdb_trace(tdb, "tdb_traverse_read_start");
ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
tdb->traverse_read--;
tdb_transaction_unlock(tdb, F_RDLCK);
return ret;
}
/*
a write style traverse - needs to get the transaction lock to
prevent deadlocks
WARNING: The data buffer given to the callback fn does NOT meet the
alignment guarantees malloc gives you.
*/
_PUBLIC_ int tdb_traverse(struct tdb_context *tdb,
tdb_traverse_func fn, void *private_data)
{
struct tdb_traverse_lock tl = { NULL, 0, 0, F_WRLCK };
int ret;
if (tdb->read_only || tdb->traverse_read) {
return tdb_traverse_read(tdb, fn, private_data);
}
if (tdb_transaction_lock(tdb, F_WRLCK, TDB_LOCK_WAIT)) {
return -1;
}
tdb->traverse_write++;
tdb_trace(tdb, "tdb_traverse_start");
ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
tdb->traverse_write--;
tdb_transaction_unlock(tdb, F_WRLCK);
return ret;
}
/* traverse the entire database - calling fn(tdb, key, data) on each element.
return -1 on error or the record count traversed
if fn is NULL then it is not called
a non-zero return value from fn() indicates that the traversal should stop
*/
static int tdb_traverse_internal(struct tdb_context *tdb,
tdb_traverse_func fn, void *private_data,
struct tdb_traverse_lock *tl)
{
TDB_DATA key, dbuf;
struct tdb_record rec;
int ret = 0, count = 0;
tdb_off_t off;
size_t recbuf_len;
recbuf_len = 4096;
key.dptr = malloc(recbuf_len);
if (key.dptr == NULL) {
return -1;
}
/* This was in the initialization, above, but the IRIX compiler
* did not like it. crh
*/
tl->next = tdb->travlocks.next;
/* fcntl locks don't stack: beware traverse inside traverse */
tdb->travlocks.next = tl;
/* tdb_next_lock places locks on the record returned, and its chain */
while ((off = tdb_next_lock(tdb, tl, &rec)) != 0) {
tdb_len_t full_len;
int nread;
if (off == TDB_NEXT_LOCK_ERR) {
ret = -1;
goto out;
}
full_len = rec.key_len + rec.data_len;
if (full_len > recbuf_len) {
recbuf_len = full_len;
/*
* No realloc, we don't need the old data and thus can
* do without the memcpy
*/
free(key.dptr);
key.dptr = malloc(recbuf_len);
if (key.dptr == NULL) {
ret = -1;
if (tdb_unlock(tdb, tl->list, tl->lock_rw)
!= 0) {
goto out;
}
if (tdb_unlock_record(tdb, tl->off) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL,
"tdb_traverse: malloc "
"failed and unlock_record "
"failed!\n"));
}
goto out;
}
}
count++;
/* now read the full record */
nread = tdb->methods->tdb_read(tdb, tl->off + sizeof(rec),
key.dptr, full_len, 0);
if (nread == -1) {
ret = -1;
if (tdb_unlock(tdb, tl->list, tl->lock_rw) != 0)
goto out;
if (tdb_unlock_record(tdb, tl->off) != 0)
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_traverse: key.dptr == NULL and unlock_record failed!\n"));
goto out;
}
key.dsize = rec.key_len;
dbuf.dptr = key.dptr + rec.key_len;
dbuf.dsize = rec.data_len;
tdb_trace_1rec_retrec(tdb, "traverse", key, dbuf);
/* Drop chain lock, call out */
if (tdb_unlock(tdb, tl->list, tl->lock_rw) != 0) {
ret = -1;
goto out;
}
if (fn && fn(tdb, key, dbuf, private_data)) {
/* They want us to terminate traversal */
tdb_trace_ret(tdb, "tdb_traverse_end", count);
if (tdb_unlock_record(tdb, tl->off) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_traverse: unlock_record failed!\n"));;
ret = -1;
}
goto out;
}
}
tdb_trace(tdb, "tdb_traverse_end");
out:
SAFE_FREE(key.dptr);
tdb->travlocks.next = tl->next;
if (ret < 0)
return -1;
else
return count;
}
/* unlock entire database with read lock */
_PUBLIC_ int tdb_unlockall_read(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_unlockall_read");
return tdb_allrecord_unlock(tdb, F_RDLCK, false);
}
/* lock entire database with read lock */
_PUBLIC_ int tdb_lockall_read(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_lockall_read");
return tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_WAIT, false);
}
/* unlock entire database with write lock - unmark only */
_PUBLIC_ int tdb_lockall_unmark(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_lockall_unmark");
return tdb_allrecord_unlock(tdb, F_WRLCK, true);
}
/* lock entire database with write lock - mark only */
_PUBLIC_ int tdb_lockall_mark(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_lockall_mark");
return tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_MARK_ONLY, false);
}
/* unlock entire database with read lock */
int tdb_unlockall_read(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_unlockall_read");
return _tdb_unlockall(tdb, F_RDLCK);
}
/* lock entire database with read lock */
int tdb_lockall_read(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_lockall_read");
return _tdb_lockall(tdb, F_RDLCK, F_SETLKW);
}
/* unlock entire database with write lock */
int tdb_unlockall(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_unlockall");
return _tdb_unlockall(tdb, F_WRLCK);
}
/* unlock entire database with write lock - unmark only */
int tdb_lockall_unmark(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_lockall_unmark");
return _tdb_unlockall(tdb, F_WRLCK | TDB_MARK_LOCK);
}
/* lock entire database with write lock */
int tdb_lockall(struct tdb_context *tdb)
{
tdb_trace(tdb, "tdb_lockall");
return _tdb_lockall(tdb, F_WRLCK, F_SETLKW);
}
/* traverse the entire database - calling fn(tdb, key, data) on each element.
return -1 on error or the record count traversed
if fn is NULL then it is not called
a non-zero return value from fn() indicates that the traversal should stop
*/
static int tdb_traverse_internal(struct tdb_context *tdb,
tdb_traverse_func fn, void *private_data,
struct tdb_traverse_lock *tl)
{
TDB_DATA key, dbuf;
struct tdb_record rec;
int ret = 0, count = 0;
tdb_off_t off;
/* This was in the initialization, above, but the IRIX compiler
* did not like it. crh
*/
tl->next = tdb->travlocks.next;
/* fcntl locks don't stack: beware traverse inside traverse */
tdb->travlocks.next = tl;
/* tdb_next_lock places locks on the record returned, and its chain */
while ((off = tdb_next_lock(tdb, tl, &rec)) != 0) {
if (off == TDB_NEXT_LOCK_ERR) {
ret = -1;
goto out;
}
count++;
/* now read the full record */
key.dptr = tdb_alloc_read(tdb, tl->off + sizeof(rec),
rec.key_len + rec.data_len);
if (!key.dptr) {
ret = -1;
if (tdb_unlock(tdb, tl->hash, tl->lock_rw) != 0)
goto out;
if (tdb_unlock_record(tdb, tl->off) != 0)
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_traverse: key.dptr == NULL and unlock_record failed!\n"));
goto out;
}
key.dsize = rec.key_len;
dbuf.dptr = key.dptr + rec.key_len;
dbuf.dsize = rec.data_len;
tdb_trace_1rec_retrec(tdb, "traverse", key, dbuf);
/* Drop chain lock, call out */
if (tdb_unlock(tdb, tl->hash, tl->lock_rw) != 0) {
ret = -1;
SAFE_FREE(key.dptr);
goto out;
}
if (fn && fn(tdb, key, dbuf, private_data)) {
/* They want us to terminate traversal */
tdb_trace_ret(tdb, "tdb_traverse_end", count);
if (tdb_unlock_record(tdb, tl->off) != 0) {
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_traverse: unlock_record failed!\n"));;
ret = -1;
}
SAFE_FREE(key.dptr);
goto out;
}
SAFE_FREE(key.dptr);
}
tdb_trace(tdb, "tdb_traverse_end");
out:
tdb->travlocks.next = tl->next;
if (ret < 0)
return -1;
else
return count;
}
