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Added tdb_append() call. Efficiently adds to an entry. Used by new messaging

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code. Also added torture tests for it.
Jeremy.
This commit is contained in:
Jeremy Allison 0001-01-01 00:00:00 +00:00
parent 04243e39cf
commit b515525a06
3 changed files with 148 additions and 12 deletions
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149
source/tdb/tdb.c
View File

@ -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)
{

1
source/tdb/tdb.h
View File

@ -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);

10
source/tdb/tdbtorture.c
View File

@ -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);