bucket, TDB_FREE_BUCKETS);
}
+static void check_list(struct tdb_context *tdb, tdb_off_t b_off)
+{
+#ifdef CCAN_TDB2_DEBUG
+ tdb_off_t off, prev = 0, first;
+ struct tdb_free_record r;
+
+ first = off = tdb_read_off(tdb, b_off);
+ while (off != 0) {
+ tdb_read_convert(tdb, off, &r, sizeof(r));
+ if (frec_magic(&r) != TDB_FREE_MAGIC)
+ abort();
+ if (prev && frec_prev(&r) != prev)
+ abort();
+ prev = off;
+ off = r.next;
+ }
+
+ if (first) {
+ tdb_read_convert(tdb, first, &r, sizeof(r));
+ if (frec_prev(&r) != prev)
+ abort();
+ }
+#endif
+}
+
/* Remove from free bucket. */
static enum TDB_ERROR remove_from_list(struct tdb_context *tdb,
tdb_off_t b_off, tdb_off_t r_off,
const struct tdb_free_record *r)
{
- tdb_off_t off;
+ tdb_off_t off, prev_next, head;
enum TDB_ERROR ecode;
- /* Front of list? */
- if (frec_prev(r) == 0) {
- off = b_off;
- } else {
- off = frec_prev(r) + offsetof(struct tdb_free_record, next);
- }
+ /* Is this only element in list? Zero out bucket, and we're done. */
+ if (frec_prev(r) == r_off)
+ return tdb_write_off(tdb, b_off, 0);
-#ifdef CCAN_TDB2_DEBUG
- if (tdb_read_off(tdb, off) != r_off) {
- return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
- "remove_from_list:"
- " %llu bad prev in list %llu",
- (long long)r_off, (long long)b_off);
- }
-#endif
-
- /* r->prev->next = r->next */
- ecode = tdb_write_off(tdb, off, r->next);
- if (ecode != TDB_SUCCESS) {
- return ecode;
- }
+ /* off = &r->prev->next */
+ off = frec_prev(r) + offsetof(struct tdb_free_record, next);
- if (r->next != 0) {
- off = r->next + offsetof(struct tdb_free_record,magic_and_prev);
- /* r->next->prev = r->prev */
+ /* Get prev->next */
+ prev_next = tdb_read_off(tdb, off);
+ if (TDB_OFF_IS_ERR(prev_next))
+ return prev_next;
+ /* If prev->next == 0, we were head: update bucket to point to next. */
+ if (prev_next == 0) {
#ifdef CCAN_TDB2_DEBUG
- if (tdb_read_off(tdb, off) & TDB_OFF_MASK != r_off) {
+ if (tdb_read_off(tdb, b_off) != r_off) {
return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
"remove_from_list:"
- " %llu bad list %llu",
- (long long)r_off, (long long)b_off);
+ " %llu head %llu on list %llu",
+ (long long)r_off,
+ (long long)tdb_read_off(tdb, b_off),
+ (long long)b_off);
}
#endif
-
- ecode = tdb_write_off(tdb, off, r->magic_and_prev);
- if (ecode != TDB_SUCCESS) {
+ ecode = tdb_write_off(tdb, b_off, r->next);
+ if (ecode != TDB_SUCCESS)
+ return ecode;
+ } else {
+ /* r->prev->next = r->next */
+ ecode = tdb_write_off(tdb, off, r->next);
+ if (ecode != TDB_SUCCESS)
return ecode;
- }
}
- return TDB_SUCCESS;
+
+ /* If we were the tail, off = &head->prev. */
+ if (r->next == 0) {
+ head = tdb_read_off(tdb, b_off);
+ if (TDB_OFF_IS_ERR(head))
+ return head;
+ off = head + offsetof(struct tdb_free_record, magic_and_prev);
+ } else {
+ /* off = &r->next->prev */
+ off = r->next + offsetof(struct tdb_free_record,
+ magic_and_prev);
+ }
+
+#ifdef CCAN_TDB2_DEBUG
+ /* *off == r */
+ if ((tdb_read_off(tdb, off) & TDB_OFF_MASK) != r_off) {
+ return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
+ "remove_from_list:"
+ " %llu bad prev in list %llu",
+ (long long)r_off, (long long)b_off);
+ }
+#endif
+ /* r->next->prev = r->prev */
+ return tdb_write_off(tdb, off, r->magic_and_prev);
}
/* Enqueue in this free bucket. */
{
struct tdb_free_record new;
enum TDB_ERROR ecode;
+ tdb_off_t prev;
uint64_t magic = (TDB_FREE_MAGIC << (64 - TDB_OFF_UPPER_STEAL));
/* We only need to set ftable_and_len; rest is set in enqueue_in_free */
new.ftable_and_len = ((uint64_t)tdb->ftable << (64 - TDB_OFF_UPPER_STEAL))
| len;
- /* prev = 0. */
- new.magic_and_prev = magic;
/* new->next = head. */
new.next = tdb_read_off(tdb, b_off);
return new.next;
}
- if (new.next) {
-#ifdef CCAN_TDB2_DEBUG
- if (tdb_read_off(tdb,
- new.next + offsetof(struct tdb_free_record,
- magic_and_prev))
- != magic) {
+ /* First element? Prev points to ourselves. */
+ if (!new.next) {
+ new.magic_and_prev = (magic | off);
+ } else {
+ /* new->prev = next->prev */
+ prev = tdb_read_off(tdb,
+ new.next + offsetof(struct tdb_free_record,
+ magic_and_prev));
+ new.magic_and_prev = prev;
+ if (frec_magic(&new) != TDB_FREE_MAGIC) {
return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
"enqueue_in_free: %llu bad head"
" prev %llu",
(long long)new.next,
- (long long)b_off);
+ (long long)prev);
}
-#endif
/* next->prev = new. */
ecode = tdb_write_off(tdb, new.next
+ offsetof(struct tdb_free_record,
if (ecode != TDB_SUCCESS) {
return ecode;
}
+
+#ifdef CCAN_TDB2_DEBUG
+ prev = tdb_read_off(tdb, frec_prev(&new)
+ + offsetof(struct tdb_free_record, next));
+ if (prev != 0) {
+ return tdb_logerr(tdb, TDB_ERR_CORRUPT, TDB_LOG_ERROR,
+ "enqueue_in_free:"
+ " %llu bad tail next ptr %llu",
+ (long long)frec_prev(&new)
+ + offsetof(struct tdb_free_record,
+ next),
+ (long long)prev);
+ }
+#endif
}
/* head = new */
ecode = tdb_write_off(tdb, b_off, off);
}
ecode = enqueue_in_free(tdb, b_off, off, len);
+ check_list(tdb, b_off);
tdb_unlock_free_bucket(tdb, b_off);
return ecode;
}
}
ecode = remove_from_list(tdb, nb_off, end, &rec);
+ check_list(tdb, nb_off);
if (ecode != TDB_SUCCESS) {
tdb_unlock_free_bucket(tdb, nb_off);
goto err;
}
ecode = remove_from_list(tdb, b_off, off, &rec);
+ check_list(tdb, b_off);
if (ecode != TDB_SUCCESS) {
goto err;
}
/* We're happy with this size: take it. */
ecode = remove_from_list(tdb, b_off, best_off, &best);
+ check_list(tdb, b_off);
if (ecode != TDB_SUCCESS) {
goto unlock_err;
}
projects / ccan / blobdiff