X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb%2Ftdb.c;h=7317a3aa521554c898d12a5e5b8f57c7dafea36f;hp=a09d567c45dc4b74391f6dabdff1cbee9e90757e;hb=d9cbd7d4454ae35e4e2f6d18a9469bf26948e4b9;hpb=e55e729c188bc483d1986145014f538389e9d368

diff --git a/ccan/tdb/tdb.c b/ccan/tdb/tdb.c
index a09d567c..7317a3aa 100644
--- a/ccan/tdb/tdb.c
+++ b/ccan/tdb/tdb.c
@@ -59,14 +59,14 @@ static void tdb_increment_seqnum(struct tdb_context *tdb)
 		return;
 	}
 
-	if (tdb_brlock(tdb, F_WRLCK, TDB_SEQNUM_OFS, 1,
-		       TDB_LOCK_WAIT|TDB_LOCK_PROBE) != 0) {
+	if (tdb_nest_lock(tdb, TDB_SEQNUM_OFS, F_WRLCK,
+			  TDB_LOCK_WAIT|TDB_LOCK_PROBE) != 0) {
 		return;
 	}
 
 	tdb_increment_seqnum_nonblock(tdb);
 
-	tdb_brunlock(tdb, F_WRLCK, TDB_SEQNUM_OFS, 1);
+	tdb_nest_unlock(tdb, TDB_SEQNUM_OFS, F_WRLCK, false);
 }
 
 static int tdb_key_compare(TDB_DATA key, TDB_DATA data, void *private_data)
@@ -190,9 +190,9 @@ static TDB_DATA _tdb_fetch(struct tdb_context *tdb, TDB_DATA key)
 
 	/* find which hash bucket it is in */
 	hash = tdb->hash_fn(&key);
-	if (!(rec_ptr = tdb_find_lock_hash(tdb,key,hash,F_RDLCK,&rec))) {
+	if (!(rec_ptr = tdb_find_lock_hash(tdb,key,hash,F_RDLCK,&rec)))
 		return tdb_null;
-	}
+
 	ret.dptr = tdb_alloc_read(tdb, rec_ptr + sizeof(rec) + rec.key_len,
 				  rec.data_len);
 	ret.dsize = rec.data_len;
@@ -213,7 +213,7 @@ TDB_DATA tdb_fetch(struct tdb_context *tdb, TDB_DATA key)
  * function. The parsing function is executed under the chain read lock, so it
  * should be fast and should not block on other syscalls.
  *
- * DONT CALL OTHER TDB CALLS FROM THE PARSER, THIS MIGHT LEAD TO SEGFAULTS.
+ * DON'T CALL OTHER TDB CALLS FROM THE PARSER, THIS MIGHT LEAD TO SEGFAULTS.
  *
  * For mmapped tdb's that do not have a transaction open it points the parsing
  * function directly at the mmap area, it avoids the malloc/memcpy in this
@@ -238,8 +238,7 @@ int tdb_parse_record(struct tdb_context *tdb, TDB_DATA key,
 	hash = tdb->hash_fn(&key);
 
 	if (!(rec_ptr = tdb_find_lock_hash(tdb,key,hash,F_RDLCK,&rec))) {
-		tdb_trace_1rec_ret(tdb, "tdb_parse_record", key,
-				   -TDB_ERR_NOEXIST);
+		tdb_trace_1rec_ret(tdb, "tdb_parse_record", key, -1);
 		tdb->ecode = TDB_ERR_NOEXIST;
 		return 0;
 	}
@@ -287,7 +286,7 @@ int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct tdb_record
 
 	if (tdb->read_only || tdb->traverse_read) return -1;
 
-	if (tdb->traverse_write != 0 || 
+	if (((tdb->traverse_write != 0) && (!TDB_DEAD(rec))) ||
 	    tdb_write_lock_record(tdb, rec_ptr) == -1) {
 		/* Someone traversing here: mark it as dead */
 		rec->magic = TDB_DEAD_MAGIC;
@@ -468,7 +467,7 @@ 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)
+		       TDB_DATA dbuf, int flag, uint32_t hash)
 {
 	struct tdb_record rec;
 	tdb_off_t rec_ptr;
@@ -594,7 +593,7 @@ static int _tdb_store(struct tdb_context *tdb, TDB_DATA key,
 }
 
 /* store an element in the database, replacing any existing element
-   with the same key 
+   with the same key
 
    return 0 on success, -1 on failure
 */
@@ -605,8 +604,7 @@ int tdb_store(struct tdb_context *tdb, TDB_DATA key, TDB_DATA dbuf, int flag)
 
 	if (tdb->read_only || tdb->traverse_read) {
 		tdb->ecode = TDB_ERR_RDONLY;
-		tdb_trace_2rec_flag_ret(tdb, "tdb_store", key, dbuf, flag,
-					-TDB_ERR_RDONLY);
+		tdb_trace_2rec_flag_ret(tdb, "tdb_store", key, dbuf, flag, -1);
 		return -1;
 	}
 
@@ -621,7 +619,6 @@ int tdb_store(struct tdb_context *tdb, TDB_DATA key, TDB_DATA dbuf, int flag)
 	return ret;
 }
 
-
 /* Append to an entry. Create if not exist. */
 int tdb_append(struct tdb_context *tdb, TDB_DATA key, TDB_DATA new_dbuf)
 {
@@ -714,7 +711,6 @@ int tdb_get_seqnum(struct tdb_context *tdb)
 	tdb_off_t seqnum=0;
 
 	tdb_ofs_read(tdb, TDB_SEQNUM_OFS, &seqnum);
-	tdb_trace_ret(tdb, "tdb_get_seqnum", seqnum);
 	return seqnum;
 }
 
@@ -735,11 +731,41 @@ 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;
 }
 
@@ -779,7 +805,7 @@ static int tdb_free_region(struct tdb_context *tdb, tdb_off_t offset, ssize_t le
 
 /*
   wipe the entire database, deleting all records. This can be done
-  very fast by using a global lock. The entire data portion of the
+  very fast by using a allrecord lock. The entire data portion of the
   file becomes a single entry in the freelist.
 
   This code carefully steps around the recovery area, leaving it alone
@@ -870,7 +896,6 @@ failed:
 	return -1;
 }
 
-
 struct traverse_state {
 	bool error;
 	struct tdb_context *dest_db;
@@ -879,9 +904,9 @@ struct traverse_state {
 /*
   traverse function for repacking
  */
-static int repack_traverse(struct tdb_context *tdb, TDB_DATA key, TDB_DATA data, void *private)
+static int repack_traverse(struct tdb_context *tdb, TDB_DATA key, TDB_DATA data, void *private_data)
 {
-	struct traverse_state *state = (struct traverse_state *)private;
+	struct traverse_state *state = (struct traverse_state *)private_data;
 	if (tdb_store(state->dest_db, key, data, TDB_INSERT) != 0) {
 		state->error = true;
 		return -1;
@@ -900,13 +925,13 @@ int tdb_repack(struct tdb_context *tdb)
 	tdb_trace(tdb, "tdb_repack");
 
 	if (tdb_transaction_start(tdb) != 0) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Failed to start transaction\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Failed to start transaction\n"));
 		return -1;
 	}
 
 	tmp_db = tdb_open("tmpdb", tdb_hash_size(tdb), TDB_INTERNAL, O_RDWR|O_CREAT, 0);
 	if (tmp_db == NULL) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Failed to create tmp_db\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Failed to create tmp_db\n"));
 		tdb_transaction_cancel(tdb);
 		return -1;
 	}
@@ -915,21 +940,21 @@ int tdb_repack(struct tdb_context *tdb)
 	state.dest_db = tmp_db;
 
 	if (tdb_traverse_read(tdb, repack_traverse, &state) == -1) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Failed to traverse copying out\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Failed to traverse copying out\n"));
 		tdb_transaction_cancel(tdb);
 		tdb_close(tmp_db);
 		return -1;		
 	}
 
 	if (state.error) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Error during traversal\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Error during traversal\n"));
 		tdb_transaction_cancel(tdb);
 		tdb_close(tmp_db);
 		return -1;
 	}
 
 	if (tdb_wipe_all(tdb) != 0) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Failed to wipe database\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Failed to wipe database\n"));
 		tdb_transaction_cancel(tdb);
 		tdb_close(tmp_db);
 		return -1;
@@ -939,14 +964,14 @@ int tdb_repack(struct tdb_context *tdb)
 	state.dest_db = tdb;
 
 	if (tdb_traverse_read(tmp_db, repack_traverse, &state) == -1) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Failed to traverse copying back\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Failed to traverse copying back\n"));
 		tdb_transaction_cancel(tdb);
 		tdb_close(tmp_db);
 		return -1;		
 	}
 
 	if (state.error) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Error during second traversal\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Error during second traversal\n"));
 		tdb_transaction_cancel(tdb);
 		tdb_close(tmp_db);
 		return -1;
@@ -955,7 +980,7 @@ int tdb_repack(struct tdb_context *tdb)
 	tdb_close(tmp_db);
 
 	if (tdb_transaction_commit(tdb) != 0) {
-		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_repack: Failed to commit\n"));
+		TDB_LOG((tdb, TDB_DEBUG_FATAL, __location__ " Failed to commit\n"));
 		return -1;
 	}
 
@@ -974,10 +999,10 @@ static void tdb_trace_write(struct tdb_context *tdb, const char *str)
 static void tdb_trace_start(struct tdb_context *tdb)
 {
 	tdb_off_t seqnum=0;
-	char msg[sizeof(tdb_off_t) * 4];
+	char msg[sizeof(tdb_off_t) * 4 + 1];
 
 	tdb_ofs_read(tdb, TDB_SEQNUM_OFS, &seqnum);
-	sprintf(msg, "%u ", seqnum);
+	snprintf(msg, sizeof(msg), "%u ", seqnum);
 	tdb_trace_write(tdb, msg);
 }
 
@@ -988,8 +1013,8 @@ static void tdb_trace_end(struct tdb_context *tdb)
 
 static void tdb_trace_end_ret(struct tdb_context *tdb, int ret)
 {
-	char msg[sizeof(ret) * 4];
-	sprintf(msg, " = %i\n", ret);
+	char msg[sizeof(ret) * 4 + 4];
+	snprintf(msg, sizeof(msg), " = %i\n", ret);
 	tdb_trace_write(tdb, msg);
 }
 
@@ -1004,10 +1029,11 @@ static void tdb_trace_record(struct tdb_context *tdb, TDB_DATA rec)
 		return;
 	}
 
+	/* snprintf here is purely cargo-cult programming. */
 	p = msg;
-	p += sprintf(p, " %zu:", rec.dsize);
+	p += snprintf(p, sizeof(msg), " %zu:", rec.dsize);
 	for (i = 0; i < rec.dsize; i++)
-		p += sprintf(p, "%02x", rec.dptr[i]);
+		p += snprintf(p, 2, "%02x", rec.dptr[i]);
 
 	tdb_trace_write(tdb, msg);
 }
@@ -1021,9 +1047,9 @@ void tdb_trace(struct tdb_context *tdb, const char *op)
 
 void tdb_trace_seqnum(struct tdb_context *tdb, uint32_t seqnum, const char *op)
 {
-	char msg[sizeof(tdb_off_t) * 4];
+	char msg[sizeof(tdb_off_t) * 4 + 1];
 
-	sprintf(msg, "%u ", seqnum);
+	snprintf(msg, sizeof(msg), "%u ", seqnum);
 	tdb_trace_write(tdb, msg);
 	tdb_trace_write(tdb, op);
 	tdb_trace_end(tdb);
@@ -1034,7 +1060,8 @@ void tdb_trace_open(struct tdb_context *tdb, const char *op,
 {
 	char msg[128];
 
-	sprintf(msg, "%s %u %#x %#x", op, hash_size, tdb_flags, open_flags);
+	snprintf(msg, sizeof(msg),
+		 "%s %u 0x%x 0x%x", op, hash_size, tdb_flags, open_flags);
 	tdb_trace_start(tdb);
 	tdb_trace_write(tdb, msg);
 	tdb_trace_end(tdb);
@@ -1089,9 +1116,9 @@ void tdb_trace_2rec_flag_ret(struct tdb_context *tdb, const char *op,
 			     TDB_DATA rec1, TDB_DATA rec2, unsigned flag,
 			     int ret)
 {
-	char msg[sizeof(ret) * 4];
+	char msg[1 + sizeof(ret) * 4];
 
-	sprintf(msg, " %#x", flag); 
+	snprintf(msg, sizeof(msg), " %#x", flag);
 	tdb_trace_start(tdb);
 	tdb_trace_write(tdb, op);
 	tdb_trace_record(tdb, rec1);