X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Fio.c;h=bb3d2192829dc504a885e06176f6a2e275c2bcd8;hp=7e5dcb73160f4a441e6e978349e04c2bca5cbaa4;hb=703cea0c78a896c658272af06306218fc0bb23cc;hpb=41e027e11e0b15100e50c14e49aaa4c2b418f431

diff --git a/ccan/tdb2/io.c b/ccan/tdb2/io.c
index 7e5dcb73..bb3d2192 100644
--- a/ccan/tdb2/io.c
+++ b/ccan/tdb2/io.c
@@ -342,7 +342,7 @@ enum TDB_ERROR tdb_write_off(struct tdb_context *tdb,
 static void *_tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset,
 			     tdb_len_t len, unsigned int prefix)
 {
-	void *buf;
+	unsigned char *buf;
 	enum TDB_ERROR ecode;
 
 	/* some systems don't like zero length malloc */
@@ -439,7 +439,7 @@ static enum TDB_ERROR tdb_expand_file(struct tdb_context *tdb,
 const void *tdb_access_read(struct tdb_context *tdb,
 			    tdb_off_t off, tdb_len_t len, bool convert)
 {
-	const void *ret = NULL;
+	void *ret = NULL;
 
 	if (likely(!(tdb->flags & TDB_CONVERT))) {
 		ret = tdb->methods->direct(tdb, off, len, false);
@@ -563,6 +563,35 @@ static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len,
 	return (char *)tdb->file->map_ptr + off;
 }
 
+void tdb_inc_seqnum(struct tdb_context *tdb)
+{
+	tdb_off_t seq;
+
+	if (likely(!(tdb->flags & TDB_CONVERT))) {
+		int64_t *direct;
+
+		direct = tdb->methods->direct(tdb,
+					      offsetof(struct tdb_header,
+						       seqnum),
+					      sizeof(*direct), true);
+		if (likely(direct)) {
+			/* Don't let it go negative, even briefly */
+			if (unlikely((*direct) + 1) < 0)
+				*direct = 0;
+			(*direct)++;
+			return;
+		}
+	}
+
+	seq = tdb_read_off(tdb, offsetof(struct tdb_header, seqnum));
+	if (!TDB_OFF_IS_ERR(seq)) {
+		seq++;
+		if (unlikely((int64_t)seq < 0))
+			seq = 0;
+		tdb_write_off(tdb, offsetof(struct tdb_header, seqnum), seq);
+	}
+}
+
 void add_stat_(struct tdb_context *tdb, uint64_t *s, size_t val)
 {
 	if ((uintptr_t)s < (uintptr_t)tdb->stats + tdb->stats->size)