diff --git a/gossipd/gossip_store.c b/gossipd/gossip_store.c index b80d22540..a00bb1c57 100644 --- a/gossipd/gossip_store.c +++ b/gossipd/gossip_store.c @@ -9,7 +9,8 @@ #define GOSSIP_STORE_FILENAME "gossip_store" struct gossip_store { - int read_fd, write_fd; + int fd; + off_t read_pos, write_pos; /* What was the size of the gossip_store when we started replaying * it? */ @@ -18,17 +19,16 @@ struct gossip_store { static void gossip_store_destroy(struct gossip_store *gs) { - if (gs->read_fd != -1) - close(gs->read_fd); - close(gs->write_fd); + close(gs->fd); } struct gossip_store *gossip_store_new(const tal_t *ctx) { struct gossip_store *gs = tal(ctx, struct gossip_store); - gs->write_fd = open(GOSSIP_STORE_FILENAME, O_RDWR|O_APPEND|O_CREAT, 0600); - gs->read_fd = open(GOSSIP_STORE_FILENAME, O_RDONLY); - gs->replaysize = lseek(gs->write_fd, 0, SEEK_END); + gs->fd = open(GOSSIP_STORE_FILENAME, O_RDWR|O_APPEND|O_CREAT, 0600); + gs->read_pos = 0; + gs->write_pos = lseek(gs->fd, 0, SEEK_END); + gs->replaysize = gs->write_pos; tal_add_destructor(gs, gossip_store_destroy); @@ -40,17 +40,11 @@ void gossip_store_append(struct gossip_store *gs, const u8 *msg) u16 msglen = tal_len(msg); beint16_t belen = cpu_to_be16(msglen); - /* FIXME: this method of detecting replayed messages is best effort - * only. It should avoid doubling the store file size on every start, - * but it'll allow the last few messages to be duplicated since replay - * and write are async, and we'll think we are done replaying a bit too - * early. */ - /* Check if we are replaying the store */ - if (lseek(gs->read_fd, 0, SEEK_CUR) < gs->replaysize) + if (pwrite(gs->fd, &belen, sizeof(belen), gs->write_pos) != 2 || + pwrite(gs->fd, msg, msglen, gs->write_pos + 2) != msglen) { return; - - write_all(gs->write_fd, &belen, sizeof(belen)); - write_all(gs->write_fd, msg, msglen); + } else + gs->write_pos += 2 + msglen; } const u8 *gossip_store_read_next(const tal_t *ctx, struct gossip_store *gs) @@ -60,22 +54,29 @@ const u8 *gossip_store_read_next(const tal_t *ctx, struct gossip_store *gs) u8 *msg; /* Did we already reach the end of the gossip_store? */ - if (gs->read_fd == -1) + if (gs->read_pos == -1) return NULL; /* Can we read one message? */ - if (!read_all(gs->read_fd, &belen, sizeof(belen))) { - gs->read_fd = -1; + if (pread(gs->fd, &belen, sizeof(belen), gs->read_pos) != 2) { + gs->read_pos = -1; return NULL; } msglen = be16_to_cpu(belen); msg = tal_arr(ctx, u8, msglen); - if (!read_all(gs->read_fd, msg, msglen)) - status_failed( - STATUS_FAIL_INTERNAL_ERROR, - "Short read from gossip-store, expected lenght %d", msglen); + if (!pread(gs->fd, msg, msglen, gs->read_pos + 2)) { + status_trace("Short read from gossip-store, expected lenght %d", + msglen); + + /* Reset write_pos to truncate this message and disable future + * reads */ + gs->write_pos = gs->read_pos; + gs->read_pos = -1; + ftruncate(gs->fd, gs->write_pos); + } else + gs->read_pos += 2 + msglen; return msg; }