#include "tdb_private.h"
TDB_DATA tdb_null;
static void tdb_increment_seqnum(struct tdb_context *tdb)
{
tdb_off_t seqnum=0;
if (!(tdb->flags & TDB_SEQNUM)) {
return;
}
if (tdb_brlock(tdb, TDB_SEQNUM_OFS, F_WRLCK, F_SETLKW, 1, 1) != 0) {
return;
}
tdb_ofs_read(tdb, TDB_SEQNUM_OFS, &seqnum);
seqnum++;
tdb_ofs_write(tdb, TDB_SEQNUM_OFS, &seqnum);
tdb_brlock(tdb, TDB_SEQNUM_OFS, F_UNLCK, F_SETLKW, 1, 1);
}
static int tdb_key_compare(TDB_DATA key, TDB_DATA data, void *private_data)
{
return memcmp(data.dptr, key.dptr, data.dsize);
}
static tdb_off_t tdb_find(struct tdb_context *tdb, TDB_DATA key, u32 hash,
struct list_struct *r)
{
tdb_off_t rec_ptr;
if (tdb_ofs_read(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1)
return 0;
while (rec_ptr) {
if (tdb_rec_read(tdb, rec_ptr, r) == -1)
return 0;
if (!TDB_DEAD(r) && hash==r->full_hash
&& key.dsize==r->key_len
&& tdb_parse_data(tdb, key, rec_ptr + sizeof(*r),
r->key_len, tdb_key_compare,
NULL) == 0) {
return rec_ptr;
}
rec_ptr = r->next;
}
return TDB_ERRCODE(TDB_ERR_NOEXIST, 0);
}
tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, u32 hash, int locktype,
struct list_struct *rec)
{
u32 rec_ptr;
if (tdb_lock(tdb, BUCKET(hash), locktype) == -1)
return 0;
if (!(rec_ptr = tdb_find(tdb, key, hash, rec)))
tdb_unlock(tdb, BUCKET(hash), locktype);
return rec_ptr;
}
static int tdb_update_hash(struct tdb_context *tdb, TDB_DATA key, u32 hash, TDB_DATA dbuf)
{
struct list_struct rec;
tdb_off_t rec_ptr;
if (!(rec_ptr = tdb_find(tdb, key, hash, &rec)))
return -1;
if (rec.rec_len < key.dsize + dbuf.dsize + sizeof(tdb_off_t)) {
tdb->ecode = TDB_SUCCESS;
return -1;
}
if (tdb->methods->tdb_write(tdb, rec_ptr + sizeof(rec) + rec.key_len,
dbuf.dptr, dbuf.dsize) == -1)
return -1;
if (dbuf.dsize != rec.data_len) {
rec.data_len = dbuf.dsize;
return tdb_rec_write(tdb, rec_ptr, &rec);
}
return 0;
}
TDB_DATA tdb_fetch(struct tdb_context *tdb, TDB_DATA key)
{
tdb_off_t rec_ptr;
struct list_struct rec;
TDB_DATA ret;
u32 hash;
hash = tdb->hash_fn(&key);
if (!(rec_ptr = tdb_find_lock_hash(tdb,key,hash,F_RDLCK,&rec)))
return tdb_null;
ret.dptr = tdb_alloc_read(tdb, rec_ptr + sizeof(rec) + rec.key_len,
rec.data_len);
ret.dsize = rec.data_len;
tdb_unlock(tdb, BUCKET(rec.full_hash), F_RDLCK);
return ret;
}
int tdb_parse_record(struct tdb_context *tdb, TDB_DATA key,
int (*parser)(TDB_DATA key, TDB_DATA data,
void *private_data),
void *private_data)
{
tdb_off_t rec_ptr;
struct list_struct rec;
int ret;
u32 hash;
hash = tdb->hash_fn(&key);
if (!(rec_ptr = tdb_find_lock_hash(tdb,key,hash,F_RDLCK,&rec))) {
return TDB_ERRCODE(TDB_ERR_NOEXIST, 0);
}
ret = tdb_parse_data(tdb, key, rec_ptr + sizeof(rec) + rec.key_len,
rec.data_len, parser, private_data);
tdb_unlock(tdb, BUCKET(rec.full_hash), F_RDLCK);
return ret;
}
static int tdb_exists_hash(struct tdb_context *tdb, TDB_DATA key, u32 hash)
{
struct list_struct rec;
if (tdb_find_lock_hash(tdb, key, hash, F_RDLCK, &rec) == 0)
return 0;
tdb_unlock(tdb, BUCKET(rec.full_hash), F_RDLCK);
return 1;
}
int tdb_exists(struct tdb_context *tdb, TDB_DATA key)
{
u32 hash = tdb->hash_fn(&key);
return tdb_exists_hash(tdb, key, hash);
}
int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct list_struct*rec)
{
tdb_off_t last_ptr, i;
struct list_struct lastrec;
if (tdb->read_only || tdb->traverse_read) return -1;
if (tdb_write_lock_record(tdb, rec_ptr) == -1) {
rec->magic = TDB_DEAD_MAGIC;
return tdb_rec_write(tdb, rec_ptr, rec);
}
if (tdb_write_unlock_record(tdb, rec_ptr) != 0)
return -1;
if (tdb_ofs_read(tdb, TDB_HASH_TOP(rec->full_hash), &i) == -1)
return -1;
for (last_ptr = 0; i != rec_ptr; last_ptr = i, i = lastrec.next)
if (tdb_rec_read(tdb, i, &lastrec) == -1)
return -1;
if (last_ptr == 0)
last_ptr = TDB_HASH_TOP(rec->full_hash);
if (tdb_ofs_write(tdb, last_ptr, &rec->next) == -1)
return -1;
if (tdb_free(tdb, rec_ptr, rec) == -1)
return -1;
return 0;
}
static int tdb_count_dead(struct tdb_context *tdb, u32 hash)
{
int res = 0;
tdb_off_t rec_ptr;
struct list_struct rec;
if (tdb_ofs_read(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1)
return 0;
while (rec_ptr) {
if (tdb_rec_read(tdb, rec_ptr, &rec) == -1)
return 0;
if (rec.magic == TDB_DEAD_MAGIC) {
res += 1;
}
rec_ptr = rec.next;
}
return res;
}
static int tdb_purge_dead(struct tdb_context *tdb, u32 hash)
{
int res = -1;
struct list_struct rec;
tdb_off_t rec_ptr;
if (tdb_lock(tdb, -1, F_WRLCK) == -1) {
return -1;
}
if (tdb_ofs_read(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1)
goto fail;
while (rec_ptr) {
tdb_off_t next;
if (tdb_rec_read(tdb, rec_ptr, &rec) == -1) {
goto fail;
}
next = rec.next;
if (rec.magic == TDB_DEAD_MAGIC
&& tdb_do_delete(tdb, rec_ptr, &rec) == -1) {
goto fail;
}
rec_ptr = next;
}
res = 0;
fail:
tdb_unlock(tdb, -1, F_WRLCK);
return res;
}
static int tdb_delete_hash(struct tdb_context *tdb, TDB_DATA key, u32 hash)
{
tdb_off_t rec_ptr;
struct list_struct rec;
int ret;
if (tdb->max_dead_records != 0) {
if (tdb_lock(tdb, BUCKET(hash), F_WRLCK) == -1)
return -1;
if (tdb_count_dead(tdb, hash) >= tdb->max_dead_records) {
tdb_purge_dead(tdb, hash);
}
if (!(rec_ptr = tdb_find(tdb, key, hash, &rec))) {
tdb_unlock(tdb, BUCKET(hash), F_WRLCK);
return -1;
}
rec.magic = TDB_DEAD_MAGIC;
ret = tdb_rec_write(tdb, rec_ptr, &rec);
}
else {
if (!(rec_ptr = tdb_find_lock_hash(tdb, key, hash, F_WRLCK,
&rec)))
return -1;
ret = tdb_do_delete(tdb, rec_ptr, &rec);
}
if (ret == 0) {
tdb_increment_seqnum(tdb);
}
if (tdb_unlock(tdb, BUCKET(rec.full_hash), F_WRLCK) != 0)
TDB_LOG((tdb, TDB_DEBUG_WARNING, "tdb_delete: WARNING tdb_unlock failed!\n"));
return ret;
}
int tdb_delete(struct tdb_context *tdb, TDB_DATA key)
{
u32 hash = tdb->hash_fn(&key);
return tdb_delete_hash(tdb, key, hash);
}
static tdb_off_t tdb_find_dead(struct tdb_context *tdb, u32 hash,
struct list_struct *r, tdb_len_t length)
{
tdb_off_t rec_ptr;
if (tdb_ofs_read(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1)
return 0;
while (rec_ptr) {
if (tdb_rec_read(tdb, rec_ptr, r) == -1)
return 0;
if (TDB_DEAD(r) && r->rec_len >= length) {
return rec_ptr;
}
rec_ptr = r->next;
}
return 0;
}
int tdb_store(struct tdb_context *tdb, TDB_DATA key, TDB_DATA dbuf, int flag)
{
struct list_struct rec;
u32 hash;
tdb_off_t rec_ptr;
char *p = NULL;
int ret = -1;
if (tdb->read_only || tdb->traverse_read) {
tdb->ecode = TDB_ERR_RDONLY;
return -1;
}
hash = tdb->hash_fn(&key);
if (tdb_lock(tdb, BUCKET(hash), F_WRLCK) == -1)
return -1;
if (flag == TDB_INSERT) {
if (tdb_exists_hash(tdb, key, hash)) {
tdb->ecode = TDB_ERR_EXISTS;
goto fail;
}
} else {
if (tdb_update_hash(tdb, key, hash, dbuf) == 0) {
goto done;
}
if (tdb->ecode == TDB_ERR_NOEXIST &&
flag == TDB_MODIFY) {
goto fail;
}
}
tdb->ecode = TDB_SUCCESS;
if (flag != TDB_INSERT)
tdb_delete_hash(tdb, key, hash);
if (!(p = (char *)malloc(key.dsize + dbuf.dsize))) {
tdb->ecode = TDB_ERR_OOM;
goto fail;
}
memcpy(p, key.dptr, key.dsize);
if (dbuf.dsize)
memcpy(p+key.dsize, dbuf.dptr, dbuf.dsize);
if (tdb->max_dead_records != 0) {
rec_ptr = tdb_find_dead(
tdb, hash, &rec,
key.dsize + dbuf.dsize + sizeof(tdb_off_t));
if (rec_ptr != 0) {
rec.key_len = key.dsize;
rec.data_len = dbuf.dsize;
rec.full_hash = hash;
rec.magic = TDB_MAGIC;
if (tdb_rec_write(tdb, rec_ptr, &rec) == -1
|| tdb->methods->tdb_write(
tdb, rec_ptr + sizeof(rec),
p, key.dsize + dbuf.dsize) == -1) {
goto fail;
}
goto done;
}
}
if (tdb_lock(tdb, -1, F_WRLCK) == -1) {
goto fail;
}
if ((tdb->max_dead_records != 0)
&& (tdb_purge_dead(tdb, hash) == -1)) {
tdb_unlock(tdb, -1, F_WRLCK);
goto fail;
}
rec_ptr = tdb_allocate(tdb, key.dsize + dbuf.dsize, &rec);
tdb_unlock(tdb, -1, F_WRLCK);
if (rec_ptr == 0) {
goto fail;
}
if (tdb_ofs_read(tdb, TDB_HASH_TOP(hash), &rec.next) == -1)
goto fail;
rec.key_len = key.dsize;
rec.data_len = dbuf.dsize;
rec.full_hash = hash;
rec.magic = TDB_MAGIC;
if (tdb_rec_write(tdb, rec_ptr, &rec) == -1
|| tdb->methods->tdb_write(tdb, rec_ptr+sizeof(rec), p, key.dsize+dbuf.dsize)==-1
|| tdb_ofs_write(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1) {
goto fail;
}
done:
ret = 0;
fail:
if (ret == 0) {
tdb_increment_seqnum(tdb);
}
SAFE_FREE(p);
tdb_unlock(tdb, BUCKET(hash), F_WRLCK);
return ret;
}
int tdb_append(struct tdb_context *tdb, TDB_DATA key, TDB_DATA new_dbuf)
{
u32 hash;
TDB_DATA dbuf;
int ret = -1;
hash = tdb->hash_fn(&key);
if (tdb_lock(tdb, BUCKET(hash), F_WRLCK) == -1)
return -1;
dbuf = tdb_fetch(tdb, key);
if (dbuf.dptr == NULL) {
dbuf.dptr = (char *)malloc(new_dbuf.dsize);
} else {
char *new_dptr = (char *)realloc(dbuf.dptr,
dbuf.dsize + new_dbuf.dsize);
if (new_dptr == NULL) {
free(dbuf.dptr);
}
dbuf.dptr = new_dptr;
}
if (dbuf.dptr == NULL) {
tdb->ecode = TDB_ERR_OOM;
goto failed;
}
memcpy(dbuf.dptr + dbuf.dsize, new_dbuf.dptr, new_dbuf.dsize);
dbuf.dsize += new_dbuf.dsize;
ret = tdb_store(tdb, key, dbuf, 0);
failed:
tdb_unlock(tdb, BUCKET(hash), F_WRLCK);
SAFE_FREE(dbuf.dptr);
return ret;
}
const char *tdb_name(struct tdb_context *tdb)
{
return tdb->name;
}
int tdb_fd(struct tdb_context *tdb)
{
return tdb->fd;
}
tdb_log_func tdb_log_fn(struct tdb_context *tdb)
{
return tdb->log.log_fn;
}
int tdb_get_seqnum(struct tdb_context *tdb)
{
tdb_off_t seqnum=0;
tdb_ofs_read(tdb, TDB_SEQNUM_OFS, &seqnum);
return seqnum;
}
int tdb_hash_size(struct tdb_context *tdb)
{
return tdb->header.hash_size;
}
size_t tdb_map_size(struct tdb_context *tdb)
{
return tdb->map_size;
}
int tdb_get_flags(struct tdb_context *tdb)
{
return tdb->flags;
}