MEDIUM: dns: Update the dns_session applet to use its own buffers

Thanks to this patch, the dns_session applet is now using its own
buffers. .rcv_buf and .snd_buf callback functions are now defined to use the
default raw functions. Functions to receive and send data have also been
updated to use the applet API and to remove any dependencies on the
stream-connectors and the channels.

diff --git a/src/dns.c b/src/dns.c
index b8d4882760950ecd79435a7b5f6bf6b78f43c30d..9c36b598e4dd63ca21e5b714beff01ae3f70459a 100644 (file)
--- a/src/dns.c
+++ b/src/dns.c
@@ -438,7 +438,6 @@ out:
  */
 static void dns_session_io_handler(struct appctx *appctx)
 {
-       struct stconn *sc = appctx_sc(appctx);
        struct dns_session *ds = appctx->svcctx;
        struct dns_ring *ring = &ds->ring;
        struct buffer *buf = &ring->buf;
@@ -447,8 +446,8 @@ static void dns_session_io_handler(struct appctx *appctx)
        size_t len, cnt, ofs;
        int ret = 0;
 
-       if (unlikely(se_fl_test(appctx->sedesc, (SE_FL_EOS|SE_FL_ERROR)))) {
-               co_skip(sc_oc(sc), co_data(sc_oc(sc)));
+       if (unlikely(applet_fl_test(appctx, APPCTX_FL_EOS|APPCTX_FL_ERROR))) {
+               applet_reset_input(appctx);
                goto out;
        }
 
@@ -467,9 +466,13 @@ static void dns_session_io_handler(struct appctx *appctx)
        /* if the connection is not established, inform the stream that we want
         * to be notified whenever the connection completes.
         */
-       if (sc_opposite(sc)->state < SC_ST_EST) {
+       if (se_fl_test(appctx->sedesc, SE_FL_APPLET_NEED_CONN)) {
                applet_need_more_data(appctx);
-               se_need_remote_conn(appctx->sedesc);
+               applet_have_more_data(appctx);
+               goto out;
+       }
+
+       if (applet_get_outbuf(appctx) == NULL) {
                applet_have_more_data(appctx);
                goto out;
        }
@@ -521,7 +524,7 @@ static void dns_session_io_handler(struct appctx *appctx)
                BUG_ON(msg_len + ofs + cnt + 1 > b_data(buf));
 
                /* retrieve available room on output channel */
-               available_room = channel_recv_max(sc_ic(sc));
+               available_room = applet_output_room(appctx);
 
                /* tx_msg_offset null means we are at the start of a new message */
                if (!ds->tx_msg_offset) {
@@ -529,7 +532,7 @@ static void dns_session_io_handler(struct appctx *appctx)
 
                        /* check if there is enough room to put message len and query id */
                        if (available_room < sizeof(slen) + sizeof(new_qid)) {
-                               sc_need_room(sc, sizeof(slen) + sizeof(new_qid));
+                               applet_have_more_data(appctx);
                                ret = 0;
                                break;
                        }
@@ -588,7 +591,7 @@ static void dns_session_io_handler(struct appctx *appctx)
 
                /* check if it remains available room on output chan */
                if (unlikely(!available_room)) {
-                       sc_need_room(sc, 1);
+                       applet_have_more_data(appctx);
                        ret = 0;
                        break;
                }
@@ -622,7 +625,7 @@ static void dns_session_io_handler(struct appctx *appctx)
 
                if (ds->tx_msg_offset) {
                        /* msg was not fully processed, we must  be awake to drain pending data */
-                       sc_need_room(sc, 0);
+                       applet_have_more_data(appctx);
                        ret = 0;
                        break;
                }
@@ -651,6 +654,11 @@ static void dns_session_io_handler(struct appctx *appctx)
         */
        __ha_barrier_load();
        if (!LIST_INLIST_ATOMIC(&ds->waiter)) {
+               if (applet_get_inbuf(appctx) == NULL) {
+                       applet_need_more_data(appctx);
+                       goto out;
+               }
+
                while (1) {
                        uint16_t query_id;
                        struct eb32_node *eb;
@@ -658,7 +666,7 @@ static void dns_session_io_handler(struct appctx *appctx)
 
                        if (!ds->rx_msg.len) {
                                /* retrieve message len */
-                               ret = co_getblk(sc_oc(sc), (char *)&msg_len, 2, 0);
+                               ret = applet_getblk(appctx, (char *)&msg_len, 2, 0);
                                if (ret <= 0) {
                                        if (ret == -1)
                                                goto error;
@@ -667,7 +675,7 @@ static void dns_session_io_handler(struct appctx *appctx)
                                }
 
                                /* mark as consumed */
-                               co_skip(sc_oc(sc), 2);
+                               applet_skip_input(appctx, 2);
 
                                /* store message len */
                                ds->rx_msg.len = ntohs(msg_len);
@@ -675,11 +683,11 @@ static void dns_session_io_handler(struct appctx *appctx)
                                        continue;
                        }
 
-                       if (co_data(sc_oc(sc)) + ds->rx_msg.offset < ds->rx_msg.len) {
+                       if (applet_input_data(appctx) + ds->rx_msg.offset < ds->rx_msg.len) {
                                /* message only partially available */
 
                                /* read available data */
-                               ret = co_getblk(sc_oc(sc), ds->rx_msg.area + ds->rx_msg.offset, co_data(sc_oc(sc)), 0);
+                               ret = applet_getblk(appctx, ds->rx_msg.area + ds->rx_msg.offset, applet_input_data(appctx), 0);
                                if (ret <= 0) {
                                        if (ret == -1)
                                                goto error;
@@ -688,10 +696,10 @@ static void dns_session_io_handler(struct appctx *appctx)
                                }
 
                                /* update message offset */
-                               ds->rx_msg.offset += co_data(sc_oc(sc));
+                               ds->rx_msg.offset += applet_input_data(appctx);
 
                                /* consume all pending data from the channel */
-                               co_skip(sc_oc(sc), co_data(sc_oc(sc)));
+                               applet_skip_input(appctx, applet_input_data(appctx));
 
                                /* we need to wait for more data */
                                applet_need_more_data(appctx);
@@ -701,7 +709,7 @@ static void dns_session_io_handler(struct appctx *appctx)
                        /* enough data is available into the channel to read the message until the end */
 
                        /* read from the channel until the end of the message */
-                       ret = co_getblk(sc_oc(sc), ds->rx_msg.area + ds->rx_msg.offset, ds->rx_msg.len - ds->rx_msg.offset, 0);
+                       ret = applet_getblk(appctx, ds->rx_msg.area + ds->rx_msg.offset, ds->rx_msg.len - ds->rx_msg.offset, 0);
                        if (ret <= 0) {
                                if (ret == -1)
                                        goto error;
@@ -710,7 +718,7 @@ static void dns_session_io_handler(struct appctx *appctx)
                        }
 
                        /* consume all data until the end of the message from the channel */
-                       co_skip(sc_oc(sc), ds->rx_msg.len - ds->rx_msg.offset);
+                       applet_skip_input(appctx, ds->rx_msg.len - ds->rx_msg.offset);
 
                        /* reset reader offset to 0 for next message reand */
                        ds->rx_msg.offset = 0;
@@ -759,11 +767,12 @@ out:
        return;
 
 close:
-       se_fl_set(appctx->sedesc, SE_FL_EOS|SE_FL_EOI);
+       applet_set_eos(appctx);
        goto out;
 
 error:
-       se_fl_set(appctx->sedesc, SE_FL_ERROR);
+       applet_set_eos(appctx);
+       applet_set_error(appctx);
        goto out;
 }
 
@@ -830,6 +839,7 @@ static int dns_session_init(struct appctx *appctx)
        s->do_log = NULL;
        s->uniq_id = 0;
 
+       se_need_remote_conn(appctx->sedesc);
        applet_expect_no_data(appctx);
        ds->appctx = appctx;
        appctx->t->expire = TICK_ETERNITY;
@@ -944,6 +954,8 @@ static struct applet dns_session_applet = {
        .obj_type = OBJ_TYPE_APPLET,
        .name = "<STRMDNS>", /* used for logging */
        .fct = dns_session_io_handler,
+       .rcv_buf = appctx_raw_rcv_buf,
+       .snd_buf = appctx_raw_snd_buf,
        .init = dns_session_init,
        .release = dns_session_release,
 };