- /*
+ /*
Trivial Database 2: traverse function.
Copyright (C) Rusty Russell 2010
-
+
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
#include "private.h"
#include <ccan/likely/likely.h>
-static int64_t traverse(struct tdb_context *tdb, int ltype,
- tdb_traverse_func fn, void *p)
+int64_t tdb_traverse_(struct tdb_context *tdb,
+ int (*fn)(struct tdb_context *,
+ TDB_DATA, TDB_DATA, void *),
+ void *p)
{
- uint64_t i, num, count = 0;
- tdb_off_t off, prev_bucket;
- struct tdb_used_record rec;
+ enum TDB_ERROR ecode;
+ struct traverse_info tinfo;
struct tdb_data k, d;
- bool finish = false;
-
- /* FIXME: Do we need to start at 0? */
- prev_bucket = tdb_lock_list(tdb, 0, ltype, TDB_LOCK_WAIT);
- if (prev_bucket != 0)
- return -1;
-
- num = (1ULL << tdb->header.v.hash_bits);
+ int64_t count = 0;
- for (i = tdb_find_nonzero_off(tdb, hash_off(tdb, 0), num);
- i != num && !finish;
- i += tdb_find_nonzero_off(tdb, hash_off(tdb, i), num - i)) {
- if (tdb_lock_list(tdb, i, ltype, TDB_LOCK_WAIT) != i)
- goto fail;
-
- off = tdb_read_off(tdb, hash_off(tdb, i));
- if (off == TDB_OFF_ERR) {
- tdb_unlock_list(tdb, i, ltype);
- goto fail;
- }
-
- /* This race can happen, but look again. */
- if (off == 0) {
- tdb_unlock_list(tdb, i, ltype);
- continue;
- }
+ if (tdb->flags & TDB_VERSION1) {
+ count = tdb1_traverse(tdb, fn, p);
+ if (count == -1)
+ return TDB_ERR_TO_OFF(tdb->last_error);
+ return count;
+ }
- /* Drop previous lock. */
- tdb_unlock_list(tdb, prev_bucket, ltype);
- prev_bucket = i;
-
- if (tdb_read_convert(tdb, off, &rec, sizeof(rec)) != 0)
- goto fail;
-
- k.dsize = rec_key_length(&rec);
- d.dsize = rec_data_length(&rec);
- if (ltype == F_RDLCK) {
- /* Read traverses can keep the lock. */
- k.dptr = (void *)tdb_access_read(tdb,
- off + sizeof(rec),
- k.dsize + d.dsize,
- false);
- } else {
- k.dptr = tdb_alloc_read(tdb, off + sizeof(rec),
- k.dsize + d.dsize);
- }
- if (!k.dptr)
- goto fail;
+ k.dptr = NULL;
+ for (ecode = first_in_hash(tdb, &tinfo, &k, &d.dsize);
+ ecode == TDB_SUCCESS;
+ ecode = next_in_hash(tdb, &tinfo, &k, &d.dsize)) {
d.dptr = k.dptr + k.dsize;
+
count++;
+ if (fn && fn(tdb, k, d, p)) {
+ free(k.dptr);
+ tdb->last_error = TDB_SUCCESS;
+ return count;
+ }
+ free(k.dptr);
+ }
- if (ltype == F_WRLCK) {
- /* Drop lock before calling out. */
- tdb_unlock_list(tdb, i, ltype);
+ if (ecode != TDB_ERR_NOEXIST) {
+ return TDB_ERR_TO_OFF(tdb->last_error = ecode);
+ }
+ tdb->last_error = TDB_SUCCESS;
+ return count;
+}
+
+enum TDB_ERROR tdb_firstkey(struct tdb_context *tdb, struct tdb_data *key)
+{
+ struct traverse_info tinfo;
+
+ if (tdb->flags & TDB_VERSION1) {
+ tdb->last_error = TDB_SUCCESS;
+ *key = tdb1_firstkey(tdb);
+ /* TDB1 didn't set error for last key. */
+ if (!key->dptr && tdb->last_error == TDB_SUCCESS) {
+ tdb->last_error = TDB_ERR_NOEXIST;
}
+ return tdb->last_error;
+ }
+
+ return tdb->last_error = first_in_hash(tdb, &tinfo, key, NULL);
+}
- if (fn && fn(tdb, k, d, p))
- finish = true;
+/* We lock twice, not very efficient. We could keep last key & tinfo cached. */
+enum TDB_ERROR tdb_nextkey(struct tdb_context *tdb, struct tdb_data *key)
+{
+ struct traverse_info tinfo;
+ struct hash_info h;
+ struct tdb_used_record rec;
- if (ltype == F_WRLCK) {
- free(k.dptr);
- /* Regain lock. FIXME: Is this necessary? */
- if (tdb_lock_list(tdb, i, ltype, TDB_LOCK_WAIT) != i)
- return -1;
-
- /* This makes deleting under ourselves a bit nicer. */
- if (tdb_read_off(tdb, hash_off(tdb, i)) == off)
- i++;
- } else {
- tdb_access_release(tdb, k.dptr);
- i++;
+ if (tdb->flags & TDB_VERSION1) {
+ struct tdb_data last_key = *key;
+ tdb->last_error = TDB_SUCCESS;
+ *key = tdb1_nextkey(tdb, last_key);
+ free(last_key.dptr);
+ /* TDB1 didn't set error for last key. */
+ if (!key->dptr && tdb->last_error == TDB_SUCCESS) {
+ tdb->last_error = TDB_ERR_NOEXIST;
}
+ return tdb->last_error;
}
- /* Drop final lock. */
- tdb_unlock_list(tdb, prev_bucket, ltype);
- return count;
+ tinfo.prev = find_and_lock(tdb, *key, F_RDLCK, &h, &rec, &tinfo);
+ free(key->dptr);
+ if (TDB_OFF_IS_ERR(tinfo.prev)) {
+ return tdb->last_error = TDB_OFF_TO_ERR(tinfo.prev);
+ }
+ tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
-fail:
- tdb_unlock_list(tdb, prev_bucket, ltype);
- return -1;
+ return tdb->last_error = next_in_hash(tdb, &tinfo, key, NULL);
}
-int64_t tdb_traverse(struct tdb_context *tdb, tdb_traverse_func fn, void *p)
+static int wipe_one(struct tdb_context *tdb,
+ TDB_DATA key, TDB_DATA data, enum TDB_ERROR *ecode)
{
- return traverse(tdb, F_WRLCK, fn, p);
+ *ecode = tdb_delete(tdb, key);
+ return (*ecode != TDB_SUCCESS);
}
-
-int64_t tdb_traverse_read(struct tdb_context *tdb,
- tdb_traverse_func fn, void *p)
+
+enum TDB_ERROR tdb_wipe_all(struct tdb_context *tdb)
{
- int64_t ret;
- bool was_ro = tdb->read_only;
- tdb->read_only = true;
- ret = traverse(tdb, F_RDLCK, fn, p);
- tdb->read_only = was_ro;
- return ret;
+ enum TDB_ERROR ecode;
+ int64_t count;
+
+ if (tdb->flags & TDB_VERSION1) {
+ if (tdb1_wipe_all(tdb) == -1)
+ return tdb->last_error;
+ return TDB_SUCCESS;
+ }
+
+ ecode = tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_WAIT, false);
+ if (ecode != TDB_SUCCESS)
+ return tdb->last_error = ecode;
+
+ /* FIXME: Be smarter. */
+ count = tdb_traverse(tdb, wipe_one, &ecode);
+ if (count < 0)
+ ecode = TDB_OFF_TO_ERR(count);
+ tdb_allrecord_unlock(tdb, F_WRLCK);
+ return tdb->last_error = ecode;
}
projects / ccan / blobdiff