From: Alexandru Ardelean Date: Wed, 5 Jul 2017 13:20:51 +0000 (+0300) Subject: ubusd: don't free messages in ubus_send_msg() anymore X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=e02813b2cc62f672127360e7515017c02df7af18;p=project%2Fubus.git ubusd: don't free messages in ubus_send_msg() anymore This makes it clear that `ubus_msg_send()` is only about sending and queue-ing messages, and has nothing to do with free-ing. It can be a bit misleading/confusing when trying to go through the code and make assumptions about whether a buffer is free'd in ubus_send_msg(), or is free'd outside. In `ubusd_proto_receive_message()` the `ubus_msg_free()` is now called before the `if (ret == -1)` check. That way, all callbacks will have their messages free'd, which is what's desired, but confusing, because: * ubusd_handle_invoke() called ubus_msg_free() before returning -1 * ubusd_handle_notify() called ubus_msg_free() before returning -1 * ubusd_handle_response() called ubus_msg_send(,,free=true) before returning -1 * ubus_msg_send() would call ubus_msg_send(,,free=false) * all other callback callers would `ubus_msg_send(,,free=true)` (free the buffers in ubus_msg_send() ) In all other places, where `ubus_msg_send(,,free=true)` an explicit `ubus_msg_free()` was added. Signed-off-by: Alexandru Ardelean --- diff --git a/ubusd.c b/ubusd.c index f060b38..ba1ff07 100644 --- a/ubusd.c +++ b/ubusd.c @@ -146,7 +146,7 @@ static void ubus_msg_enqueue(struct ubus_client *cl, struct ubus_msg_buf *ub) } /* takes the msgbuf reference */ -void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub, bool free) +void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub) { int written; @@ -160,7 +160,7 @@ void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub, bool free) written = 0; if (written >= ub->len + sizeof(ub->hdr)) - goto out; + return; cl->txq_ofs = written; @@ -168,10 +168,6 @@ void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub, bool free) uloop_fd_add(&cl->sock, ULOOP_READ | ULOOP_WRITE | ULOOP_EDGE_TRIGGER); } ubus_msg_enqueue(cl, ub); - -out: - if (free) - ubus_msg_free(ub); } static struct ubus_msg_buf *ubus_msg_head(struct ubus_client *cl) diff --git a/ubusd.h b/ubusd.h index 5031ed4..991a59f 100644 --- a/ubusd.h +++ b/ubusd.h @@ -67,7 +67,7 @@ struct ubus_path { extern const char *ubusd_acl_dir; struct ubus_msg_buf *ubus_msg_new(void *data, int len, bool shared); -void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub, bool free); +void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub); void ubus_msg_free(struct ubus_msg_buf *ub); struct blob_attr **ubus_parse_msg(struct blob_attr *msg); diff --git a/ubusd_event.c b/ubusd_event.c index 984f341..0469c20 100644 --- a/ubusd_event.c +++ b/ubusd_event.c @@ -129,7 +129,7 @@ static void ubusd_send_event_msg(struct ubus_msg_buf **ub, struct ubus_client *c *objid_ptr = htonl(obj->id.id); (*ub)->hdr.seq = ++event_seq; - ubus_msg_send(obj->client, *ub, false); + ubus_msg_send(obj->client, *ub); } static bool strmatch_len(const char *s1, const char *s2, int *len) diff --git a/ubusd_monitor.c b/ubusd_monitor.c index 82d0333..a192206 100644 --- a/ubusd_monitor.c +++ b/ubusd_monitor.c @@ -76,7 +76,8 @@ ubusd_monitor_message(struct ubus_client *cl, struct ubus_msg_buf *ub, bool send ub = ubus_msg_new(mb.head, blob_raw_len(mb.head), true); ub->hdr.type = UBUS_MSG_MONITOR; ub->hdr.seq = ++m->seq; - ubus_msg_send(m->cl, ub, true); + ubus_msg_send(m->cl, ub); + ubus_msg_free(ub); } } diff --git a/ubusd_proto.c b/ubusd_proto.c index 72da7a7..441d084 100644 --- a/ubusd_proto.c +++ b/ubusd_proto.c @@ -89,7 +89,8 @@ ubus_proto_send_msg_from_blob(struct ubus_client *cl, struct ubus_msg_buf *ub, ub->hdr.type = type; ub->fd = fd; - ubus_msg_send(cl, ub, true); + ubus_msg_send(cl, ub); + ubus_msg_free(ub); } static bool ubusd_send_hello(struct ubus_client *cl) @@ -102,14 +103,15 @@ static bool ubusd_send_hello(struct ubus_client *cl) return false; ubus_msg_init(ub, UBUS_MSG_HELLO, 0, cl->id.id); - ubus_msg_send(cl, ub, true); + ubus_msg_send(cl, ub); + ubus_msg_free(ub); return true; } static int ubusd_send_pong(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr) { ub->hdr.type = UBUS_MSG_DATA; - ubus_msg_send(cl, ub, false); + ubus_msg_send(cl, ub); return 0; } @@ -274,7 +276,6 @@ static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, blob_buf_init(&b, 0); ubusd_forward_invoke(cl, obj, method, ub, attr[UBUS_ATTR_DATA]); - ubus_msg_free(ub); return -1; } @@ -322,7 +323,6 @@ static int ubusd_handle_notify(struct ubus_client *cl, struct ubus_msg_buf *ub, blob_put_int8(&b, UBUS_ATTR_NO_REPLY, 1); ubusd_forward_invoke(cl, s->subscriber, method, ub, attr[UBUS_ATTR_DATA]); } - ubus_msg_free(ub); return -1; } @@ -359,11 +359,8 @@ static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub goto error; ub->hdr.peer = blob_get_u32(attr[UBUS_ATTR_OBJID]); - ubus_msg_send(cl, ub, true); - return -1; - + ubus_msg_send(cl, ub); error: - ubus_msg_free(ub); return -1; } @@ -454,18 +451,20 @@ void ubusd_proto_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub if (ub->hdr.type != UBUS_MSG_STATUS && ub->hdr.type != UBUS_MSG_INVOKE) ubus_msg_close_fd(ub); + /* Note: no callback should free the `ub` buffer + that's always done right after the callback finishes */ if (cb) ret = cb(cl, ub, ubus_parse_msg(ub->data)); else ret = UBUS_STATUS_INVALID_COMMAND; + ubus_msg_free(ub); + if (ret == -1) return; - ubus_msg_free(ub); - *retmsg_data = htonl(ret); - ubus_msg_send(cl, retmsg, false); + ubus_msg_send(cl, retmsg); } struct ubus_client *ubusd_proto_new_client(int fd, uloop_fd_handler cb) @@ -526,7 +525,8 @@ void ubus_notify_subscription(struct ubus_object *obj) return; ubus_msg_init(ub, UBUS_MSG_NOTIFY, ++obj->invoke_seq, 0); - ubus_msg_send(obj->client, ub, true); + ubus_msg_send(obj->client, ub); + ubus_msg_free(ub); } void ubus_notify_unsubscribe(struct ubus_subscription *s) @@ -540,7 +540,8 @@ void ubus_notify_unsubscribe(struct ubus_subscription *s) ub = ubus_msg_from_blob(false); if (ub != NULL) { ubus_msg_init(ub, UBUS_MSG_UNSUBSCRIBE, ++s->subscriber->invoke_seq, 0); - ubus_msg_send(s->subscriber->client, ub, true); + ubus_msg_send(s->subscriber->client, ub); + ubus_msg_free(ub); } ubus_unsubscribe(s);