From 29ab853e0750499b0fb9625d32fd67d9695b7007 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 24 Sep 2010 15:39:43 +0930 Subject: [PATCH] tdb: automatically identify Jenkins hash tdbs If the caller to tdb_open_ex() doesn't specify a hash, and tdb_old_hash doesn't match, try tdb_jenkins_hash. This was Metze's idea: it makes life simpler, especially with the upcoming TDB_INCOMPATIBLE_HASH flag. Signed-off-by: Rusty Russell (cherry picked from commit ccac258d14dda7d8a994a7b80474ce6d85478a6d) Signed-off-by: Stefan Metzmacher --- lib/tdb/common/open.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) diff --git a/lib/tdb/common/open.c b/lib/tdb/common/open.c index 3d972caee2..0633bc1f5f 100644 --- a/lib/tdb/common/open.c +++ b/lib/tdb/common/open.c @@ -37,7 +37,7 @@ void tdb_header_hash(struct tdb_context *tdb, TDB_DATA hash_key; uint32_t tdb_magic = TDB_MAGIC; - hash_key.dptr = (unsigned char *)TDB_MAGIC_FOOD; + hash_key.dptr = discard_const_p(unsigned char, TDB_MAGIC_FOOD); hash_key.dsize = sizeof(TDB_MAGIC_FOOD); *magic1_hash = tdb->hash_fn(&hash_key); @@ -149,6 +149,23 @@ static void null_log_fn(struct tdb_context *tdb, enum tdb_debug_level level, con { } +static bool check_header_hash(struct tdb_context *tdb, + bool default_hash, uint32_t *m1, uint32_t *m2) +{ + tdb_header_hash(tdb, m1, m2); + if (tdb->header.magic1_hash == *m1 && + tdb->header.magic2_hash == *m2) { + return true; + } + + /* If they explicitly set a hash, always respect it. */ + if (!default_hash) + return false; + + /* Otherwise, try the other inbuilt hash. */ + tdb->hash_fn = tdb_jenkins_hash; + return check_header_hash(tdb, false, m1, m2); +} struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags, int open_flags, mode_t mode, @@ -161,9 +178,8 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags, unsigned char *vp; uint32_t vertest; unsigned v; - uint32_t magic1_hash; - uint32_t magic2_hash; const char *hash_alg; + uint32_t magic1, magic2; if (!(tdb = (struct tdb_context *)calloc(1, sizeof *tdb))) { /* Can't log this */ @@ -185,10 +201,10 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags, if (hash_fn) { tdb->hash_fn = hash_fn; - hash_alg = "user defined"; + hash_alg = "the user defined"; } else { tdb->hash_fn = tdb_old_hash; - hash_alg = "default"; + hash_alg = "either default"; } /* cache the page size */ @@ -288,23 +304,20 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags, goto fail; } - tdb_header_hash(tdb, &magic1_hash, &magic2_hash); - if ((tdb->header.magic1_hash == 0) && (tdb->header.magic2_hash == 0)) { /* older TDB without magic hash references */ - } else if ((tdb->header.magic1_hash != magic1_hash) || - (tdb->header.magic2_hash != magic2_hash)) { + } else if (!check_header_hash(tdb, !hash_fn, &magic1, &magic2)) { TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: " - "%s was not created with the %s hash function we are using\n" + "%s was not created with %s hash function we are using\n" "magic1_hash[0x%08X %s 0x%08X] " "magic2_hash[0x%08X %s 0x%08X]\n", name, hash_alg, tdb->header.magic1_hash, - (tdb->header.magic1_hash == magic1_hash) ? "==" : "!=", - magic1_hash, + (tdb->header.magic1_hash == magic1) ? "==" : "!=", + magic1, tdb->header.magic2_hash, - (tdb->header.magic2_hash == magic2_hash) ? "==" : "!=", - magic2_hash)); + (tdb->header.magic2_hash == magic2) ? "==" : "!=", + magic2)); errno = EINVAL; goto fail; } -- 2.34.1