X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb%2Ftdb.c;h=cb0b88519d961ea292bcfd7d2b8db2772f50ad37;hp=0db9a358381c94a2e540430a271891255f10b730;hb=f7b3eb1ecf6935dbf2b6c283e848ebfbaaeca47c;hpb=91ddc0b7f90986495f014217451361c07fdcd856 diff --git a/ccan/tdb/tdb.c b/ccan/tdb/tdb.c index 0db9a358..cb0b8851 100644 --- a/ccan/tdb/tdb.c +++ b/ccan/tdb/tdb.c @@ -59,13 +59,14 @@ static void tdb_increment_seqnum(struct tdb_context *tdb) return; } - if (tdb_brlock(tdb, TDB_SEQNUM_OFS, F_WRLCK, F_SETLKW, 1, 1) != 0) { + if (tdb_brlock(tdb, F_WRLCK, TDB_SEQNUM_OFS, 1, + TDB_LOCK_WAIT|TDB_LOCK_PROBE) != 0) { return; } tdb_increment_seqnum_nonblock(tdb); - tdb_brlock(tdb, TDB_SEQNUM_OFS, F_UNLCK, F_SETLKW, 1, 1); + tdb_brunlock(tdb, F_WRLCK, TDB_SEQNUM_OFS, 1); } static int tdb_key_compare(TDB_DATA key, TDB_DATA data, void *private_data) @@ -76,7 +77,7 @@ static int tdb_key_compare(TDB_DATA key, TDB_DATA data, void *private_data) /* Returns 0 on fail. On success, return offset of record, and fills in rec */ static tdb_off_t tdb_find(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, - struct list_struct *r) + struct tdb_record *r) { tdb_off_t rec_ptr; @@ -110,7 +111,7 @@ static tdb_off_t tdb_find(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, /* As tdb_find, but if you succeed, keep the lock */ tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, int locktype, - struct list_struct *rec) + struct tdb_record *rec) { uint32_t rec_ptr; @@ -121,6 +122,7 @@ tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t has return rec_ptr; } +static TDB_DATA _tdb_fetch(struct tdb_context *tdb, TDB_DATA key); /* update an entry in place - this only works if the new data size is <= the old data size and the key exists. @@ -128,13 +130,32 @@ tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t has */ static int tdb_update_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, TDB_DATA dbuf) { - struct list_struct rec; + struct tdb_record rec; tdb_off_t rec_ptr; /* find entry */ if (!(rec_ptr = tdb_find(tdb, key, hash, &rec))) return -1; + /* it could be an exact duplicate of what is there - this is + * surprisingly common (eg. with a ldb re-index). */ + if (rec.key_len == key.dsize && + rec.data_len == dbuf.dsize && + rec.full_hash == hash) { + TDB_DATA data = _tdb_fetch(tdb, key); + if (data.dsize == dbuf.dsize && + memcmp(data.dptr, dbuf.dptr, data.dsize) == 0) { + if (data.dptr) { + free(data.dptr); + } + return 0; + } + if (data.dptr) { + free(data.dptr); + } + } + + /* must be long enough key, data and tailer */ if (rec.rec_len < key.dsize + dbuf.dsize + sizeof(tdb_off_t)) { tdb->ecode = TDB_SUCCESS; /* Not really an error */ @@ -163,7 +184,7 @@ static int tdb_update_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, static TDB_DATA _tdb_fetch(struct tdb_context *tdb, TDB_DATA key) { tdb_off_t rec_ptr; - struct list_struct rec; + struct tdb_record rec; TDB_DATA ret; uint32_t hash; @@ -209,7 +230,7 @@ int tdb_parse_record(struct tdb_context *tdb, TDB_DATA key, void *private_data) { tdb_off_t rec_ptr; - struct list_struct rec; + struct tdb_record rec; int ret; uint32_t hash; @@ -240,7 +261,7 @@ int tdb_parse_record(struct tdb_context *tdb, TDB_DATA key, */ static int tdb_exists_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash) { - struct list_struct rec; + struct tdb_record rec; if (tdb_find_lock_hash(tdb, key, hash, F_RDLCK, &rec) == 0) return 0; @@ -259,10 +280,10 @@ int tdb_exists(struct tdb_context *tdb, TDB_DATA key) } /* actually delete an entry in the database given the offset */ -int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct list_struct *rec) +int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct tdb_record *rec) { tdb_off_t last_ptr, i; - struct list_struct lastrec; + struct tdb_record lastrec; if (tdb->read_only || tdb->traverse_read) return -1; @@ -298,7 +319,7 @@ static int tdb_count_dead(struct tdb_context *tdb, uint32_t hash) { int res = 0; tdb_off_t rec_ptr; - struct list_struct rec; + struct tdb_record rec; /* read in the hash top */ if (tdb_ofs_read(tdb, TDB_HASH_TOP(hash), &rec_ptr) == -1) @@ -322,7 +343,7 @@ static int tdb_count_dead(struct tdb_context *tdb, uint32_t hash) static int tdb_purge_dead(struct tdb_context *tdb, uint32_t hash) { int res = -1; - struct list_struct rec; + struct tdb_record rec; tdb_off_t rec_ptr; if (tdb_lock(tdb, -1, F_WRLCK) == -1) { @@ -358,7 +379,7 @@ static int tdb_purge_dead(struct tdb_context *tdb, uint32_t hash) static int tdb_delete_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash) { tdb_off_t rec_ptr; - struct list_struct rec; + struct tdb_record rec; int ret; if (tdb->max_dead_records != 0) { @@ -421,7 +442,7 @@ int tdb_delete(struct tdb_context *tdb, TDB_DATA key) * See if we have a dead record around with enough space */ static tdb_off_t tdb_find_dead(struct tdb_context *tdb, uint32_t hash, - struct list_struct *r, tdb_len_t length) + struct tdb_record *r, tdb_len_t length) { tdb_off_t rec_ptr; @@ -449,7 +470,7 @@ static tdb_off_t tdb_find_dead(struct tdb_context *tdb, uint32_t hash, static int _tdb_store(struct tdb_context *tdb, TDB_DATA key, TDB_DATA dbuf, int flag, uint32_t hash) { - struct list_struct rec; + struct tdb_record rec; tdb_off_t rec_ptr; char *p = NULL; int ret = -1; @@ -714,11 +735,41 @@ int tdb_get_flags(struct tdb_context *tdb) void tdb_add_flags(struct tdb_context *tdb, unsigned flags) { + if ((flags & TDB_ALLOW_NESTING) && + (flags & TDB_DISALLOW_NESTING)) { + tdb->ecode = TDB_ERR_NESTING; + TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_add_flags: " + "allow_nesting and disallow_nesting are not allowed together!")); + return; + } + + if (flags & TDB_ALLOW_NESTING) { + tdb->flags &= ~TDB_DISALLOW_NESTING; + } + if (flags & TDB_DISALLOW_NESTING) { + tdb->flags &= ~TDB_ALLOW_NESTING; + } + tdb->flags |= flags; } void tdb_remove_flags(struct tdb_context *tdb, unsigned flags) { + if ((flags & TDB_ALLOW_NESTING) && + (flags & TDB_DISALLOW_NESTING)) { + tdb->ecode = TDB_ERR_NESTING; + TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_remove_flags: " + "allow_nesting and disallow_nesting are not allowed together!")); + return; + } + + if (flags & TDB_ALLOW_NESTING) { + tdb->flags |= TDB_DISALLOW_NESTING; + } + if (flags & TDB_DISALLOW_NESTING) { + tdb->flags |= TDB_ALLOW_NESTING; + } + tdb->flags &= ~flags; } @@ -738,7 +789,7 @@ void tdb_enable_seqnum(struct tdb_context *tdb) */ static int tdb_free_region(struct tdb_context *tdb, tdb_off_t offset, ssize_t length) { - struct list_struct rec; + struct tdb_record rec; if (length <= sizeof(rec)) { /* the region is not worth adding */ return 0; @@ -787,7 +838,7 @@ int tdb_wipe_all(struct tdb_context *tdb) } if (recovery_head != 0) { - struct list_struct rec; + struct tdb_record rec; if (tdb->methods->tdb_read(tdb, recovery_head, &rec, sizeof(rec), DOCONV()) == -1) { TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_wipe_all: failed to read recovery record\n")); return -1;