tdb2: TDB_SEQNUM and tdb_get_seqnum support.

[ccan] / ccan / tdb2 / tdb.c

diff --git a/ccan/tdb2/tdb.c b/ccan/tdb2/tdb.c
index 02642f58c97427b27a03e9bd8c7bd0c17d087328..569c3d04de90241217754a9602da34f747eaa22b 100644 (file)
--- a/ccan/tdb2/tdb.c
+++ b/ccan/tdb2/tdb.c
@@ -2,9 +2,6 @@
 #include <ccan/asprintf/asprintf.h>
 #include <stdarg.h>
 
-/* The null return. */
-struct tdb_data tdb_null = { .dptr = NULL, .dsize = 0 };
-
 static enum TDB_ERROR update_rec_hdr(struct tdb_context *tdb,
                                     tdb_off_t off,
                                     tdb_len_t keylen,
@@ -66,7 +63,9 @@ static enum TDB_ERROR replace_data(struct tdb_context *tdb,
                return ecode;
        }
 
-       /* FIXME: tdb_increment_seqnum(tdb); */
+       if (tdb->flags & TDB_SEQNUM)
+               tdb_inc_seqnum(tdb);
+
        return TDB_SUCCESS;
 }
 
@@ -82,6 +81,9 @@ static enum TDB_ERROR update_data(struct tdb_context *tdb,
                /* Put a zero in; future versions may append other data. */
                ecode = tdb->methods->twrite(tdb, off + dbuf.dsize, "", 1);
        }
+       if (tdb->flags & TDB_SEQNUM)
+               tdb_inc_seqnum(tdb);
+
        return ecode;
 }
 
@@ -243,6 +245,21 @@ enum TDB_ERROR tdb_fetch(struct tdb_context *tdb, struct tdb_data key,
        return ecode;
 }
 
+bool tdb_exists(struct tdb_context *tdb, TDB_DATA key)
+{
+       tdb_off_t off;
+       struct tdb_used_record rec;
+       struct hash_info h;
+
+       off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+       if (TDB_OFF_IS_ERR(off)) {
+               return false;
+       }
+       tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+
+       return off ? true : false;
+}
+
 enum TDB_ERROR tdb_delete(struct tdb_context *tdb, struct tdb_data key)
 {
        tdb_off_t off;
@@ -273,6 +290,9 @@ enum TDB_ERROR tdb_delete(struct tdb_context *tdb, struct tdb_data key)
                                + rec_data_length(&rec)
                                + rec_extra_padding(&rec));
 
+       if (tdb->flags & TDB_SEQNUM)
+               tdb_inc_seqnum(tdb);
+
 unlock:
        tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
        return ecode;
@@ -296,11 +316,14 @@ void tdb_add_flag(struct tdb_context *tdb, unsigned flag)
                break;
        case TDB_NOMMAP:
                tdb->flags |= TDB_NOMMAP;
-               tdb_munmap(tdb);
+               tdb_munmap(tdb->file);
                break;
        case TDB_NOSYNC:
                tdb->flags |= TDB_NOSYNC;
                break;
+       case TDB_SEQNUM:
+               tdb->flags |= TDB_SEQNUM;
+               break;
        default:
                tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
                           "tdb_add_flag: Unknown flag %u", flag);
@@ -325,6 +348,9 @@ void tdb_remove_flag(struct tdb_context *tdb, unsigned flag)
        case TDB_NOSYNC:
                tdb->flags &= ~TDB_NOSYNC;
                break;
+       case TDB_SEQNUM:
+               tdb->flags &= ~TDB_SEQNUM;
+               break;
        default:
                tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
                           "tdb_remove_flag: Unknown flag %u", flag);
@@ -377,3 +403,57 @@ enum TDB_ERROR COLD tdb_logerr(struct tdb_context *tdb,
        errno = saved_errno;
        return ecode;
 }
+
+enum TDB_ERROR tdb_parse_record_(struct tdb_context *tdb,
+                                TDB_DATA key,
+                                enum TDB_ERROR (*parse)(TDB_DATA key,
+                                                        TDB_DATA data,
+                                                        void *p),
+                                void *p)
+{
+       tdb_off_t off;
+       struct tdb_used_record rec;
+       struct hash_info h;
+       TDB_DATA data;
+       enum TDB_ERROR ecode;
+
+       off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+       if (TDB_OFF_IS_ERR(off)) {
+               return off;
+       }
+
+       if (!off) {
+               ecode = TDB_ERR_NOEXIST;
+       } else {
+               data.dsize = rec_data_length(&rec);
+               data.dptr = (void *)tdb_access_read(tdb,
+                                                   off + sizeof(rec)
+                                                   + key.dsize,
+                                                   data.dsize, false);
+               if (TDB_PTR_IS_ERR(data.dptr)) {
+                       ecode = TDB_PTR_ERR(data.dptr);
+               } else {
+                       ecode = parse(key, data, p);
+                       tdb_access_release(tdb, data.dptr);
+               }
+       }
+
+       tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+       return ecode;
+}
+
+const char *tdb_name(const struct tdb_context *tdb)
+{
+       return tdb->name;
+}
+
+int64_t tdb_get_seqnum(struct tdb_context *tdb)
+{
+       return tdb_read_off(tdb, offsetof(struct tdb_header, seqnum));
+}
+       
+
+int tdb_fd(const struct tdb_context *tdb)
+{
+       return tdb->file->fd;
+}