diff options
Diffstat (limited to 'source3/tdb')
| -rw-r--r-- | source3/tdb/tdb.c | 149 | ||||
| -rw-r--r-- | source3/tdb/tdb.h | 1 | ||||
| -rw-r--r-- | source3/tdb/tdbtorture.c | 10 |
3 files changed, 148 insertions, 12 deletions
diff --git a/source3/tdb/tdb.c b/source3/tdb/tdb.c index e539376ac7..f309bdd315 100644 --- a/source3/tdb/tdb.c +++ b/source3/tdb/tdb.c @@ -4,7 +4,7 @@ Copyright (C) Andrew Tridgell 1999-2000 Copyright (C) Luke Kenneth Casson Leighton 2000 Copyright (C) Paul `Rusty' Russell 2000 - Copyright (C) Jeremy Allison 2000 + Copyright (C) Jeremy Allison 2000-2003 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -1018,37 +1018,35 @@ const char *tdb_errorstr(TDB_CONTEXT *tdb) /* update an entry in place - this only works if the new data size is <= the old data size and the key exists. - on failure return -1 + on failure return -1. */ + static int tdb_update(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf) { struct list_struct rec; tdb_off rec_ptr; - int ret = -1; /* find entry */ - if (!(rec_ptr = tdb_find_lock(tdb, key, F_WRLCK, &rec))) + if (!(rec_ptr = tdb_find(tdb, key, tdb_hash(&key), &rec))) return -1; /* must be long enough key, data and tailer */ if (rec.rec_len < key.dsize + dbuf.dsize + sizeof(tdb_off)) { tdb->ecode = TDB_SUCCESS; /* Not really an error */ - goto out; + return -1; } if (tdb_write(tdb, rec_ptr + sizeof(rec) + rec.key_len, dbuf.dptr, dbuf.dsize) == -1) - goto out; + return -1; if (dbuf.dsize != rec.data_len) { /* update size */ rec.data_len = dbuf.dsize; - ret = rec_write(tdb, rec_ptr, &rec); - } else - ret = 0; - out: - tdb_unlock(tdb, BUCKET(rec.full_hash), F_WRLCK); - return ret; + return rec_write(tdb, rec_ptr, &rec); + } + + return 0; } /* find an entry in the database given a key */ @@ -1476,6 +1474,133 @@ fail: goto out; } +/* Attempt to append data to an entry in place - this only works if the new data size + is <= the old data size and the key exists. + on failure return -1. Record must be locked before calling. +*/ +static int tdb_append_inplace(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA new_dbuf) +{ + struct list_struct rec; + tdb_off rec_ptr; + + /* find entry */ + if (!(rec_ptr = tdb_find(tdb, key, tdb_hash(&key), &rec))) + return -1; + + /* Append of 0 is always ok. */ + if (new_dbuf.dsize == 0) + return 0; + + /* must be long enough for key, old data + new data and tailer */ + if (rec.rec_len < key.dsize + rec.data_len + new_dbuf.dsize + sizeof(tdb_off)) { + /* No room. */ + tdb->ecode = TDB_SUCCESS; /* Not really an error */ + return -1; + } + + if (tdb_write(tdb, rec_ptr + sizeof(rec) + rec.key_len + rec.data_len, + new_dbuf.dptr, new_dbuf.dsize) == -1) + return -1; + + /* update size */ + rec.data_len += new_dbuf.dsize; + return rec_write(tdb, rec_ptr, &rec); +} + +/* Append to an entry. Create if not exist. */ + +int tdb_append(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA new_dbuf) +{ + struct list_struct rec; + u32 hash; + tdb_off rec_ptr; + char *p = NULL; + int ret = 0; + size_t new_data_size = 0; + + /* find which hash bucket it is in */ + hash = tdb_hash(&key); + if (!tdb_keylocked(tdb, hash)) + return -1; + if (tdb_lock(tdb, BUCKET(hash), F_WRLCK) == -1) + return -1; + + /* first try in-place. */ + if (tdb_append_inplace(tdb, key, new_dbuf) == 0) + goto out; + + /* reset the error code potentially set by the tdb_append_inplace() */ + tdb->ecode = TDB_SUCCESS; + + /* find entry */ + if (!(rec_ptr = tdb_find(tdb, key, hash, &rec))) { + if (tdb->ecode != TDB_ERR_NOEXIST) + goto fail; + + /* Not found - create. */ + + ret = tdb_store(tdb, key, new_dbuf, TDB_INSERT); + goto out; + } + + new_data_size = rec.data_len + new_dbuf.dsize; + + /* Copy key+old_value+value *before* allocating free space in case malloc + fails and we are left with a dead spot in the tdb. */ + + if (!(p = (char *)malloc(key.dsize + new_data_size))) { + tdb->ecode = TDB_ERR_OOM; + goto fail; + } + + /* Copy the key in place. */ + memcpy(p, key.dptr, key.dsize); + + /* Now read the old data into place. */ + if (rec.data_len && + tdb_read(tdb, rec_ptr + sizeof(rec) + rec.key_len, p + key.dsize, rec.data_len, 0) == -1) + goto fail; + + /* Finally append the new data. */ + if (new_dbuf.dsize) + memcpy(p+key.dsize+rec.data_len, new_dbuf.dptr, new_dbuf.dsize); + + /* delete any existing record - if it doesn't exist we don't + care. Doing this first reduces fragmentation, and avoids + coalescing with `allocated' block before it's updated. */ + + tdb_delete(tdb, key); + + if (!(rec_ptr = tdb_allocate(tdb, key.dsize + new_data_size, &rec))) + goto fail; + + /* Read hash top into next ptr */ + if (ofs_read(tdb, TDB_HASH_TOP(hash), &rec.next) == -1) + goto fail; + + rec.key_len = key.dsize; + rec.data_len = new_data_size; + rec.full_hash = hash; + rec.magic = TDB_MAGIC; + + /* write out and point the top of the hash chain at it */ + if (rec_write(tdb, rec_ptr, &rec) == -1 + || tdb_write(tdb, rec_ptr+sizeof(rec), p, key.dsize+new_data_size)==-1 + || ofs_write(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1) { + /* Need to tdb_unallocate() here */ + goto fail; + } + + out: + SAFE_FREE(p); + tdb_unlock(tdb, BUCKET(hash), F_WRLCK); + return ret; + +fail: + ret = -1; + goto out; +} + static int tdb_already_open(dev_t device, ino_t ino) { diff --git a/source3/tdb/tdb.h b/source3/tdb/tdb.h index dda89d0355..9a356885e5 100644 --- a/source3/tdb/tdb.h +++ b/source3/tdb/tdb.h @@ -115,6 +115,7 @@ const char *tdb_errorstr(TDB_CONTEXT *tdb); TDB_DATA tdb_fetch(TDB_CONTEXT *tdb, TDB_DATA key); int tdb_delete(TDB_CONTEXT *tdb, TDB_DATA key); int tdb_store(TDB_CONTEXT *tdb, TDB_DATA key, TDB_DATA dbuf, int flag); +int tdb_append(TDB_CONTEXT *tdb, TDB_DATA key); int tdb_close(TDB_CONTEXT *tdb); TDB_DATA tdb_firstkey(TDB_CONTEXT *tdb); TDB_DATA tdb_nextkey(TDB_CONTEXT *tdb, TDB_DATA key); diff --git a/source3/tdb/tdbtorture.c b/source3/tdb/tdbtorture.c index c4d912a147..e27bbff990 100644 --- a/source3/tdb/tdbtorture.c +++ b/source3/tdb/tdbtorture.c @@ -21,6 +21,7 @@ #define REOPEN_PROB 30 #define DELETE_PROB 8 #define STORE_PROB 4 +#define APPEND_PROB 6 #define LOCKSTORE_PROB 0 #define TRAVERSE_PROB 20 #define CULL_PROB 100 @@ -122,6 +123,15 @@ static void addrec_db(void) } #endif +#if APPEND_PROB + if (random() % APPEND_PROB == 0) { + if (tdb_append(db, key, data) != 0) { + fatal("tdb_append failed"); + } + goto next; + } +#endif + #if LOCKSTORE_PROB if (random() % LOCKSTORE_PROB == 0) { tdb_chainlock(db, lockkey); |