Channel rotate pipe between sessiond and the consumers

[lttng-tools.git] / src / common / kernel-consumer / kernel-consumer.c

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index 5619024661d462dc56c79bacfb9fa433b66049a3..f7704b46564a63273dabe03b9e181b4846ed4292 100644 (file)
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -60,7 +60,11 @@ int lttng_kconsumer_take_snapshot(struct lttng_consumer_stream *stream)
        int infd = stream->wait_fd;
 
        ret = kernctl_snapshot(infd);
-       if (ret != 0) {
+       /*
+        * -EAGAIN is not an error, it just means that there is no data to
+        *  be read.
+        */
+       if (ret != 0 && ret != -EAGAIN) {
                PERROR("Getting sub-buffer snapshot.");
        }
 
@@ -654,6 +658,8 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 
                new_stream->chan = channel;
                new_stream->wait_fd = fd;
+               consumer_stream_update_channel_attributes(new_stream,
+                               channel);
                switch (channel->output) {
                case CONSUMER_CHANNEL_SPLICE:
                        new_stream->output = LTTNG_EVENT_SPLICE;
@@ -1072,6 +1078,72 @@ int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                }
                break;
        }
+       case LTTNG_CONSUMER_SET_CHANNEL_ROTATE_PIPE:
+       {
+               int channel_rotate_pipe;
+               int flags;
+
+               ret_code = LTTCOMM_CONSUMERD_SUCCESS;
+               /* Successfully received the command's type. */
+               ret = consumer_send_status_msg(sock, ret_code);
+               if (ret < 0) {
+                       goto error_fatal;
+               }
+
+               ret = lttcomm_recv_fds_unix_sock(sock, &channel_rotate_pipe, 1);
+               if (ret != (ssize_t) sizeof(channel_rotate_pipe)) {
+                       ERR("Failed to receive channel rotate pipe");
+                       goto error_fatal;
+               }
+
+               DBG("Received channel rotate pipe (%d)", channel_rotate_pipe);
+               ctx->channel_rotate_pipe = channel_rotate_pipe;
+               /* Set the pipe as non-blocking. */
+               ret = fcntl(channel_rotate_pipe, F_GETFL, 0);
+               if (ret == -1) {
+                       PERROR("fcntl get flags of the channel rotate pipe");
+                       goto error_fatal;
+               }
+               flags = ret;
+
+               ret = fcntl(channel_rotate_pipe, F_SETFL, flags | O_NONBLOCK);
+               if (ret == -1) {
+                       PERROR("fcntl set O_NONBLOCK flag of the channel rotate pipe");
+                       goto error_fatal;
+               }
+               DBG("Channel rotate pipe set as non-blocking");
+               ret_code = LTTCOMM_CONSUMERD_SUCCESS;
+               ret = consumer_send_status_msg(sock, ret_code);
+               if (ret < 0) {
+                       goto error_fatal;
+               }
+               break;
+       }
+       case LTTNG_CONSUMER_ROTATE_RENAME:
+       {
+               DBG("Consumer rename session %" PRIu64 " after rotation, old path = \"%s\", new path = \"%s\"",
+                               msg.u.rotate_rename.session_id,
+                               msg.u.rotate_rename.old_path,
+                               msg.u.rotate_rename.new_path);
+               ret = lttng_consumer_rotate_rename(msg.u.rotate_rename.old_path,
+                               msg.u.rotate_rename.new_path,
+                               msg.u.rotate_rename.uid,
+                               msg.u.rotate_rename.gid,
+                               msg.u.rotate_rename.relayd_id);
+               if (ret < 0) {
+                       ERR("Rotate rename failed");
+                       ret_code = LTTCOMM_CONSUMERD_CHAN_NOT_FOUND;
+               }
+
+               health_code_update();
+
+               ret = consumer_send_status_msg(sock, ret_code);
+               if (ret < 0) {
+                       /* Somehow, the session daemon is not responding anymore. */
+                       goto end_nosignal;
+               }
+               break;
+       }
        case LTTNG_CONSUMER_MKDIR:
        {
                DBG("Consumer mkdir %s in session %" PRIu64,