fix message buffering

diff --git a/ubusd.c b/ubusd.c
index 798761dc7b51508463374ecd12f0b99dfbd41de8..a1636aa1847dbaf5c980d8f3616ad5c5526ab2d7 100644 (file)
--- a/ubusd.c
+++ b/ubusd.c
@@ -90,31 +90,56 @@ static int ubus_msg_writev(int fd, struct ubus_msg_buf *ub, int offset)
        }
 }
 
+static void ubus_msg_enqueue(struct ubus_client *cl, struct ubus_msg_buf *ub)
+{
+       if (cl->tx_queue[cl->txq_tail])
+               return;
+
+       cl->tx_queue[cl->txq_tail] = ub;
+       cl->txq_tail = (cl->txq_tail + 1) % ARRAY_SIZE(cl->tx_queue);
+}
+
 /* takes the msgbuf reference */
-void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub)
+void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub, bool free)
 {
        int written;
 
-       if (cl->buf_head)
-               goto queue;
+       if (!cl->tx_queue[cl->txq_cur]) {
+               written = ubus_msg_writev(cl->sock.fd, ub, 0);
+               if (written >= ub->len + sizeof(ub->hdr))
+                       goto out;
+
+               if (written < 0)
+                       written = 0;
 
-       written = ubus_msg_writev(cl->sock.fd, ub, 0);
-       if (written > 0 && written < ub->len + sizeof(ub->hdr)) {
-               cl->buf_head_ofs = written;
+               cl->txq_ofs = written;
 
                /* get an event once we can write to the socket again */
                uloop_fd_add(&cl->sock, ULOOP_READ | ULOOP_WRITE | ULOOP_EDGE_TRIGGER);
-               goto queue;
        }
+       ubus_msg_enqueue(cl, ub);
 
-       ubus_msg_free(ub);
-       return;
+out:
+       if (free)
+               ubus_msg_free(ub);
+}
 
-queue:
-       ub = ubus_msg_unshare(ub);
-       ub->next = NULL;
-       *cl->buf_tail = ub;
-       cl->buf_tail = &ub->next;
+static struct ubus_msg_buf *ubus_msg_head(struct ubus_client *cl)
+{
+       return cl->tx_queue[cl->txq_cur];
+}
+
+static void ubus_msg_dequeue(struct ubus_client *cl)
+{
+       struct ubus_msg_buf *ub = ubus_msg_head(cl);
+
+       if (!ub)
+               return;
+
+       ubus_msg_free(ub);
+       cl->txq_ofs = 0;
+       cl->tx_queue[cl->txq_cur] = NULL;
+       cl->txq_cur = (cl->txq_cur + 1) % ARRAY_SIZE(cl->tx_queue);
 }
 
 static void handle_client_disconnect(struct ubus_client *cl)
@@ -126,6 +151,9 @@ static void handle_client_disconnect(struct ubus_client *cl)
                ubusd_free_object(obj);
        }
 
+       while (ubus_msg_head(cl))
+               ubus_msg_dequeue(cl);
+
        ubus_free_id(&clients, &cl->id);
        uloop_fd_delete(&cl->sock);
        close(cl->sock.fd);
@@ -138,11 +166,10 @@ static void client_cb(struct uloop_fd *sock, unsigned int events)
        struct ubus_msg_buf *ub;
 
        /* first try to tx more pending data */
-       while (cl->buf_head) {
-               struct ubus_msg_buf *ub = cl->buf_head;
+       while ((ub = ubus_msg_head(cl))) {
                int written;
 
-               written = ubus_msg_writev(sock->fd, ub, cl->buf_head_ofs);
+               written = ubus_msg_writev(sock->fd, ub, cl->txq_ofs);
                if (written < 0) {
                        switch(errno) {
                        case EINTR:
@@ -156,19 +183,16 @@ static void client_cb(struct uloop_fd *sock, unsigned int events)
                if (written == 0)
                        break;
 
-               cl->buf_head_ofs += written;
-               if (cl->buf_head_ofs < ub->len + sizeof(ub->hdr))
+               cl->txq_ofs += written;
+               if (cl->txq_ofs < ub->len + sizeof(ub->hdr))
                        break;
 
-               cl->buf_head_ofs = 0;
-               cl->buf_head = ub->next;
-               if (!cl->buf_head)
-                       cl->buf_tail = &cl->buf_head;
+               ubus_msg_dequeue(cl);
        }
 
        /* prevent further ULOOP_WRITE events if we don't have data
         * to send anymore */
-       if (!cl->buf_head && (events & ULOOP_WRITE))
+       if (!ubus_msg_head(cl) && (events & ULOOP_WRITE))
                uloop_fd_add(sock, ULOOP_READ | ULOOP_EDGE_TRIGGER);
 
 retry:
@@ -220,7 +244,7 @@ retry:
        }
 
 out:
-       if (!sock->eof || cl->buf_head)
+       if (!sock->eof || ubus_msg_head(cl))
                return;
 
 disconnect:

diff --git a/ubusd.h b/ubusd.h
index c82896cbcd1dc5877000f6d21d0b8e73f86c0d99..cb6bba01bddac679dcce8dfb3043ddcde43c192a 100644 (file)
--- a/ubusd.h
+++ b/ubusd.h
@@ -14,7 +14,6 @@
 #define UBUS_OBJ_HASH_BITS     4
 
 struct ubus_msg_buf {
-       struct ubus_msg_buf *next;
        uint32_t refcount; /* ~0: uses external data buffer */
        struct ubus_msghdr hdr;
        struct blob_attr *data;
@@ -25,22 +24,17 @@ struct ubus_client {
        struct ubus_id id;
        struct uloop_fd sock;
 
+       struct list_head objects;
+
+       struct ubus_msg_buf *tx_queue[UBUSD_CLIENT_BACKLOG];
+       unsigned int txq_cur, txq_tail, txq_ofs;
+
+       struct ubus_msg_buf *pending_msg;
+       int pending_msg_offset;
        struct {
                struct ubus_msghdr hdr;
                struct blob_attr data;
        } hdrbuf;
-
-       struct list_head objects;
-
-       int pending_msg_offset;
-       struct ubus_msg_buf *pending_msg;
-
-       unsigned int buf_head_ofs;
-       struct ubus_msg_buf *buf_head;
-       struct ubus_msg_buf **buf_tail;
-
-       struct ubus_msg_buf *requests[UBUSD_CLIENT_BACKLOG];
-       unsigned int req_head, req_tail;
 };
 
 struct ubus_path {
@@ -49,7 +43,7 @@ struct ubus_path {
 };
 
 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);
+void ubus_msg_send(struct ubus_client *cl, struct ubus_msg_buf *ub, bool free);
 struct ubus_msg_buf *ubus_msg_ref(struct ubus_msg_buf *ub);
 void ubus_msg_free(struct ubus_msg_buf *ub);
 

diff --git a/ubusd_proto.c b/ubusd_proto.c
index 2e84556495dd84cc35521df622a453b5de21c7d9..3333330be3a04e92150d6a0d99810c08602818ed 100644 (file)
--- a/ubusd_proto.c
+++ b/ubusd_proto.c
@@ -58,14 +58,14 @@ 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);
+       ubus_msg_send(cl, ub, true);
        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, ubus_msg_ref(ub));
+       ubus_msg_send(cl, ub, false);
        return 0;
 }
 
@@ -86,7 +86,7 @@ static int ubusd_handle_publish(struct ubus_client *cl, struct ubus_msg_buf *ub,
        if (!ub)
                return UBUS_STATUS_NO_DATA;
 
-       ubus_msg_send(cl, ub);
+       ubus_msg_send(cl, ub, true);
        return 0;
 }
 
@@ -111,7 +111,7 @@ static void ubusd_send_obj(struct ubus_client *cl, struct ubus_msg_buf *ub, stru
        if (!ub)
                return;
 
-       ubus_msg_send(cl, ub);
+       ubus_msg_send(cl, ub, true);
 }
 
 static int ubusd_handle_lookup(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
@@ -195,7 +195,7 @@ static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub,
 
        ub->hdr.type = UBUS_MSG_INVOKE;
        ub->hdr.peer = cl->id.id;
-       ubus_msg_send(obj->client, ub);
+       ubus_msg_send(obj->client, ub, true);
 
        return -1;
 }
@@ -221,7 +221,7 @@ static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub
                goto error;
 
        ub->hdr.peer = blob_get_int32(attr[UBUS_ATTR_OBJID]);
-       ubus_msg_send(cl, ub);
+       ubus_msg_send(cl, ub, true);
        return -1;
 
 error:
@@ -260,7 +260,7 @@ void ubusd_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub)
        ubus_msg_free(ub);
 
        *retmsg_data = htonl(ret);
-       ubus_msg_send(cl, ubus_msg_ref(retmsg));
+       ubus_msg_send(cl, retmsg, false);
 }
 
 static void __init ubusd_proto_init(void)