Fix: race with the viewer and readiness of streams

[lttng-tools.git] / src / common / relayd / relayd.c

diff --git a/src/common/relayd/relayd.c b/src/common/relayd/relayd.c
index bb20a64a0cc5d6cb8ffc04f2439c0c581f71803b..ccb23c065ca7aaeb8037fc30a42016fd7c9c9f3b 100644 (file)
--- a/src/common/relayd/relayd.c
+++ b/src/common/relayd/relayd.c
@@ -26,7 +26,7 @@
 #include <common/common.h>
 #include <common/defaults.h>
 #include <common/sessiond-comm/relayd.h>
-#include <common/index/lttng-index.h>
+#include <common/index/ctf-index.h>
 
 #include "relayd.h"
 
@@ -116,6 +116,50 @@ error:
        return ret;
 }
 
+/*
+ * Starting at 2.4, RELAYD_CREATE_SESSION takes additional parameters to
+ * support the live reading capability.
+ */
+static int relayd_create_session_2_4(struct lttcomm_relayd_sock *rsock,
+               uint64_t *session_id, char *session_name, char *hostname,
+               int session_live_timer, unsigned int snapshot)
+{
+       int ret;
+       struct lttcomm_relayd_create_session_2_4 msg;
+
+       strncpy(msg.session_name, session_name, sizeof(msg.session_name));
+       strncpy(msg.hostname, hostname, sizeof(msg.hostname));
+       msg.live_timer = htobe32(session_live_timer);
+       msg.snapshot = htobe32(snapshot);
+
+       /* Send command */
+       ret = send_command(rsock, RELAYD_CREATE_SESSION, &msg, sizeof(msg), 0);
+       if (ret < 0) {
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
+/*
+ * RELAYD_CREATE_SESSION from 2.1 to 2.3.
+ */
+static int relayd_create_session_2_1(struct lttcomm_relayd_sock *rsock,
+               uint64_t *session_id)
+{
+       int ret;
+
+       /* Send command */
+       ret = send_command(rsock, RELAYD_CREATE_SESSION, NULL, 0, 0);
+       if (ret < 0) {
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
 /*
  * Send a RELAYD_CREATE_SESSION command to the relayd with the given socket and
  * set session_id of the relayd if we have a successful reply from the relayd.
@@ -123,7 +167,9 @@ error:
  * On success, return 0 else a negative value which is either an errno error or
  * a lttng error code from the relayd.
  */
-int relayd_create_session(struct lttcomm_relayd_sock *rsock, uint64_t *session_id)
+int relayd_create_session(struct lttcomm_relayd_sock *rsock, uint64_t *session_id,
+               char *session_name, char *hostname, int session_live_timer,
+               unsigned int snapshot)
 {
        int ret;
        struct lttcomm_relayd_status_session reply;
@@ -133,8 +179,19 @@ int relayd_create_session(struct lttcomm_relayd_sock *rsock, uint64_t *session_i
 
        DBG("Relayd create session");
 
-       /* Send command */
-       ret = send_command(rsock, RELAYD_CREATE_SESSION, NULL, 0, 0);
+       switch(rsock->minor) {
+               case 1:
+               case 2:
+               case 3:
+                       ret = relayd_create_session_2_1(rsock, session_id);
+                       break;
+               case 4:
+               default:
+                       ret = relayd_create_session_2_4(rsock, session_id, session_name,
+                                       hostname, session_live_timer, snapshot);
+                       break;
+       }
+
        if (ret < 0) {
                goto error;
        }
@@ -236,6 +293,59 @@ error:
        return ret;
 }
 
+/*
+ * Inform the relay that all the streams for the current channel has been sent.
+ *
+ * On success return 0 else return ret_code negative value.
+ */
+int relayd_streams_sent(struct lttcomm_relayd_sock *rsock)
+{
+       int ret;
+       struct lttcomm_relayd_generic_reply reply;
+
+       /* Code flow error. Safety net. */
+       assert(rsock);
+
+       DBG("Relayd sending streams sent.");
+
+       /* This feature was introduced in 2.4, ignore it for earlier versions. */
+       if (rsock->minor < 4) {
+               ret = 0;
+               goto end;
+       }
+
+       /* Send command */
+       ret = send_command(rsock, RELAYD_STREAMS_SENT, NULL, 0, 0);
+       if (ret < 0) {
+               goto error;
+       }
+
+       /* Waiting for reply */
+       ret = recv_reply(rsock, (void *) &reply, sizeof(reply));
+       if (ret < 0) {
+               goto error;
+       }
+
+       /* Back to host bytes order. */
+       reply.ret_code = be32toh(reply.ret_code);
+
+       /* Return session id or negative ret code. */
+       if (reply.ret_code != LTTNG_OK) {
+               ret = -1;
+               ERR("Relayd streams sent replied error %d", reply.ret_code);
+               goto error;
+       } else {
+               /* Success */
+               ret = 0;
+       }
+
+       DBG("Relayd streams sent success");
+
+error:
+end:
+       return ret;
+}
+
 /*
  * Check version numbers on the relayd.
  * If major versions are compatible, we assign minor_to_use to the
@@ -634,7 +744,7 @@ error:
 int relayd_end_data_pending(struct lttcomm_relayd_sock *rsock, uint64_t id,
                unsigned int *is_data_inflight)
 {
-       int ret;
+       int ret, recv_ret;
        struct lttcomm_relayd_end_data_pending msg;
        struct lttcomm_relayd_generic_reply reply;
 
@@ -657,15 +767,15 @@ int relayd_end_data_pending(struct lttcomm_relayd_sock *rsock, uint64_t id,
                goto error;
        }
 
-       reply.ret_code = be32toh(reply.ret_code);
-       if (reply.ret_code < 0) {
-               ret = reply.ret_code;
+       recv_ret = be32toh(reply.ret_code);
+       if (recv_ret < 0) {
+               ret = recv_ret;
                goto error;
        }
 
-       *is_data_inflight = reply.ret_code;
+       *is_data_inflight = recv_ret;
 
-       DBG("Relayd end data pending is data inflight: %d", reply.ret_code);
+       DBG("Relayd end data pending is data inflight: %d", recv_ret);
 
        return 0;
 
@@ -677,7 +787,7 @@ error:
  * Send index to the relayd.
  */
 int relayd_send_index(struct lttcomm_relayd_sock *rsock,
-               struct lttng_packet_index *index, uint64_t relay_stream_id,
+               struct ctf_packet_index *index, uint64_t relay_stream_id,
                uint64_t net_seq_num)
 {
        int ret;