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 <ardeleanalex@gmail.com>

diff --git a/ubusd.c b/ubusd.c
index f060b380ce4fd442f1d160a0ab383b67fcffe5b8..ba1ff07720fa3da7cf5576eecfddc1c9530ba391 100644 (file)
--- 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 5031ed455dd0c97dc948b92c4c238f7d2aa233ce..991a59fe04def2500e58421a37112034fe96c35f 100644 (file)
--- 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 984f341eecea25f27731ef4678fc303753543e0a..0469c20aed590f7b3757e4fbb2485a23794a8aa9 100644 (file)
--- 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 82d03330b8bc5048d6bdd3f4ca963180b0f5e784..a192206ec90b48b321419ee6fde09abaac98e04b 100644 (file)
--- 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 72da7a73f22f4bf2176fa93a605b8a5bfa99f87d..441d08490b39dc54e6a50f715c68dd7041486594 100644 (file)
--- 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);