X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb%2Ftraverse.c;h=d329ef4da4030c095e530b0d7b05b344c2256305;hp=6397930b469da5385663cee6987b2568af5d0a03;hb=c4c5fed020ba44b9930119672a36a1cb33aff090;hpb=2cad878947b3abd9d30841d6b80a5146479ac709

diff --git a/ccan/tdb/traverse.c b/ccan/tdb/traverse.c
index 6397930b..d329ef4d 100644
--- a/ccan/tdb/traverse.c
+++ b/ccan/tdb/traverse.c
@@ -27,9 +27,12 @@
 
 #include "tdb_private.h"
 
-/* Uses traverse lock: 0 = finish, -1 = error, other = record offset */
-static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tlock,
-			 struct list_struct *rec)
+#define TDB_NEXT_LOCK_ERR ((tdb_off_t)-1)
+
+/* Uses traverse lock: 0 = finish, TDB_NEXT_LOCK_ERR = error,
+   other = record offset */
+static tdb_off_t tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tlock,
+			 struct tdb_record *rec)
 {
 	int want_next = (tlock->off != 0);
 
@@ -71,7 +74,7 @@ static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tloc
 		}
 
 		if (tdb_lock(tdb, tlock->hash, tlock->lock_rw) == -1)
-			return -1;
+			return TDB_NEXT_LOCK_ERR;
 
 		/* No previous record?  Start at top of chain. */
 		if (!tlock->off) {
@@ -99,6 +102,7 @@ static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tloc
 
 			/* Detect infinite loops. From "Shlomi Yaakobovich" <Shlomi@exanet.com>. */
 			if (tlock->off == rec->next) {
+				tdb->ecode = TDB_ERR_CORRUPT;
 				TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_next_lock: loop detected.\n"));
 				goto fail;
 			}
@@ -121,13 +125,14 @@ static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tloc
 		want_next = 0;
 	}
 	/* We finished iteration without finding anything */
-	return TDB_ERRCODE(TDB_SUCCESS, 0);
+	tdb->ecode = TDB_SUCCESS;
+	return 0;
 
  fail:
 	tlock->off = 0;
 	if (tdb_unlock(tdb, tlock->hash, tlock->lock_rw) != 0)
 		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_next_lock: On error unlock failed!\n"));
-	return -1;
+	return TDB_NEXT_LOCK_ERR;
 }
 
 /* traverse the entire database - calling fn(tdb, key, data) on each element.
@@ -140,8 +145,9 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 				 struct tdb_traverse_lock *tl)
 {
 	TDB_DATA key, dbuf;
-	struct list_struct rec;
-	int ret, count = 0;
+	struct tdb_record rec;
+	int ret = 0, count = 0;
+	tdb_off_t off;
 
 	/* This was in the initializaton, above, but the IRIX compiler
 	 * did not like it.  crh
@@ -152,7 +158,11 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 	tdb->travlocks.next = tl;
 
 	/* tdb_next_lock places locks on the record returned, and its chain */
-	while ((ret = tdb_next_lock(tdb, tl, &rec)) > 0) {
+	while ((off = tdb_next_lock(tdb, tl, &rec)) != 0) {
+		if (off == TDB_NEXT_LOCK_ERR) {
+			ret = -1;
+			goto out;
+		}
 		count++;
 		/* now read the full record */
 		key.dptr = tdb_alloc_read(tdb, tl->off + sizeof(rec), 
@@ -169,10 +179,7 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 		dbuf.dptr = key.dptr + rec.key_len;
 		dbuf.dsize = rec.data_len;
 
-		tdb_trace(tdb, "traverse ");
-		tdb_trace_record(tdb, key);
-		tdb_trace_record(tdb, dbuf);
-		tdb_trace(tdb, "\n");
+		tdb_trace_1rec_retrec(tdb, "traverse", key, dbuf);
 
 		/* Drop chain lock, call out */
 		if (tdb_unlock(tdb, tl->hash, tl->lock_rw) != 0) {
@@ -182,8 +189,7 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 		}
 		if (fn && fn(tdb, key, dbuf, private_data)) {
 			/* They want us to terminate traversal */
-			tdb_trace(tdb, "tdb_traverse_end = %i\n", count);
-			ret = count;
+			tdb_trace_ret(tdb, "tdb_traverse_end", count);
 			if (tdb_unlock_record(tdb, tl->off) != 0) {
 				TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_traverse: unlock_record failed!\n"));;
 				ret = -1;
@@ -193,7 +199,7 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 		}
 		SAFE_FREE(key.dptr);
 	}
-	tdb_trace(tdb, "tdb_traverse_end\n");
+	tdb_trace(tdb, "tdb_traverse_end");
 out:
 	tdb->travlocks.next = tl->next;
 	if (ret < 0)
@@ -214,18 +220,16 @@ int tdb_traverse_read(struct tdb_context *tdb,
 
 	/* we need to get a read lock on the transaction lock here to
 	   cope with the lock ordering semantics of solaris10 */
-	if (tdb->traverse_read == 0 && tdb_transaction_lock(tdb, F_RDLCK)) {
+	if (tdb_transaction_lock(tdb, F_RDLCK)) {
 		return -1;
 	}
 
 	tdb->traverse_read++;
-	tdb_trace(tdb, "tdb_traverse_read_start\n");
+	tdb_trace(tdb, "tdb_traverse_read_start");
 	ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
 	tdb->traverse_read--;
 
-	if (tdb->traverse_read == 0) {
-		tdb_transaction_unlock(tdb);
-	}
+	tdb_transaction_unlock(tdb, F_RDLCK);
 
 	return ret;
 }
@@ -247,19 +251,16 @@ int tdb_traverse(struct tdb_context *tdb,
 		return tdb_traverse_read(tdb, fn, private_data);
 	}
 
-	/* Nested traversals: transaction lock doesn't nest. */
-	if (tdb->traverse_write == 0 && tdb_transaction_lock(tdb, F_WRLCK)) {
+	if (tdb_transaction_lock(tdb, F_WRLCK)) {
 		return -1;
 	}
 
 	tdb->traverse_write++;
-	tdb_trace(tdb, "tdb_traverse_start\n");
+	tdb_trace(tdb, "tdb_traverse_start");
 	ret = tdb_traverse_internal(tdb, fn, private_data, &tl);
 	tdb->traverse_write--;
 
-	if (tdb->traverse_write == 0) {
-		tdb_transaction_unlock(tdb);
-	}
+	tdb_transaction_unlock(tdb, F_WRLCK);
 
 	return ret;
 }
@@ -269,7 +270,8 @@ int tdb_traverse(struct tdb_context *tdb,
 TDB_DATA tdb_firstkey(struct tdb_context *tdb)
 {
 	TDB_DATA key;
-	struct list_struct rec;
+	struct tdb_record rec;
+	tdb_off_t off;
 
 	/* release any old lock */
 	if (tdb_unlock_record(tdb, tdb->travlocks.off) != 0)
@@ -278,17 +280,16 @@ TDB_DATA tdb_firstkey(struct tdb_context *tdb)
 	tdb->travlocks.lock_rw = F_RDLCK;
 
 	/* Grab first record: locks chain and returned record. */
-	if (tdb_next_lock(tdb, &tdb->travlocks, &rec) <= 0) {
-		tdb_trace(tdb, "tdb_firstkey = ENOENT\n");
+	off = tdb_next_lock(tdb, &tdb->travlocks, &rec);
+	if (off == 0 || off == TDB_NEXT_LOCK_ERR) {
+		tdb_trace_retrec(tdb, "tdb_firstkey", tdb_null);
 		return tdb_null;
 	}
 	/* now read the key */
 	key.dsize = rec.key_len;
 	key.dptr =tdb_alloc_read(tdb,tdb->travlocks.off+sizeof(rec),key.dsize);
 
-	tdb_trace(tdb, "tdb_firstkey = ");
-	tdb_trace_record(tdb, key);
-	tdb_trace(tdb, "\n");
+	tdb_trace_retrec(tdb, "tdb_firstkey", key);
 
 	/* Unlock the hash chain of the record we just read. */
 	if (tdb_unlock(tdb, tdb->travlocks.hash, tdb->travlocks.lock_rw) != 0)
@@ -301,8 +302,9 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 {
 	uint32_t oldhash;
 	TDB_DATA key = tdb_null;
-	struct list_struct rec;
+	struct tdb_record rec;
 	unsigned char *k = NULL;
+	tdb_off_t off;
 
 	/* Is locked key the old key?  If so, traverse will be reliable. */
 	if (tdb->travlocks.off) {
@@ -314,9 +316,8 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 		    || memcmp(k, oldkey.dptr, oldkey.dsize) != 0) {
 			/* No, it wasn't: unlock it and start from scratch */
 			if (tdb_unlock_record(tdb, tdb->travlocks.off) != 0) {
-				tdb_trace(tdb, "tdb_nextkey ");
-				tdb_trace_record(tdb, oldkey);
-				tdb_trace(tdb, "= ENOENT\n");
+				tdb_trace_1rec_retrec(tdb, "tdb_nextkey",
+						      oldkey, tdb_null);
 				SAFE_FREE(k);
 				return tdb_null;
 			}
@@ -334,9 +335,7 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 		/* No previous element: do normal find, and lock record */
 		tdb->travlocks.off = tdb_find_lock_hash(tdb, oldkey, tdb->hash_fn(&oldkey), tdb->travlocks.lock_rw, &rec);
 		if (!tdb->travlocks.off) {
-			tdb_trace(tdb, "tdb_nextkey ");
-			tdb_trace_record(tdb, oldkey);
-			tdb_trace(tdb, "= ENOENT\n");
+			tdb_trace_1rec_retrec(tdb, "tdb_nextkey", oldkey, tdb_null);
 			return tdb_null;
 		}
 		tdb->travlocks.hash = BUCKET(rec.full_hash);
@@ -349,7 +348,8 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 
 	/* Grab next record: locks chain and returned record,
 	   unlocks old record */
-	if (tdb_next_lock(tdb, &tdb->travlocks, &rec) > 0) {
+	off = tdb_next_lock(tdb, &tdb->travlocks, &rec);
+	if (off != TDB_NEXT_LOCK_ERR && off != 0) {
 		key.dsize = rec.key_len;
 		key.dptr = tdb_alloc_read(tdb, tdb->travlocks.off+sizeof(rec),
 					  key.dsize);
@@ -360,11 +360,7 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 	/* Unlock the chain of old record */
 	if (tdb_unlock(tdb, BUCKET(oldhash), tdb->travlocks.lock_rw) != 0)
 		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_nextkey: WARNING tdb_unlock failed!\n"));
-	tdb_trace(tdb, "tdb_nextkey ");
-	tdb_trace_record(tdb, oldkey);
-	tdb_trace(tdb, "= ");
-	tdb_trace_record(tdb, key);
-	tdb_trace(tdb, "\n");
+	tdb_trace_1rec_retrec(tdb, "tdb_nextkey", oldkey, key);
 	return key;
 }