Rename data_available to data_pending

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

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index f802c462d4393565d5c3da60be70bd6b8d1cad3e..5a716859a386236fd480fbf1bb133b96a52012e7 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -310,10 +310,21 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                rcu_read_unlock();
                return -ENOSYS;
        }
-       case LTTNG_CONSUMER_DATA_AVAILABLE:
+       case LTTNG_CONSUMER_DATA_PENDING:
        {
-               rcu_read_unlock();
-               return -ENOSYS;
+               int32_t ret;
+               uint64_t id = msg.u.data_pending.session_id;
+
+               DBG("UST consumer data pending command for id %" PRIu64, id);
+
+               ret = consumer_data_pending(id);
+
+               /* Send back returned value to session daemon */
+               ret = lttcomm_send_unix_sock(sock, &ret, sizeof(ret));
+               if (ret < 0) {
+                       PERROR("send data pending ret code");
+               }
+               break;
        }
        default:
                break;
@@ -512,3 +523,35 @@ int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream *stream)
 error:
        return ret;
 }
+
+/*
+ * Check if data is still being extracted from the buffers for a specific
+ * stream. Consumer data lock MUST be acquired before calling this function
+ * and the stream lock.
+ *
+ * Return 1 if the traced data are still getting read else 0 meaning that the
+ * data is available for trace viewer reading.
+ */
+int lttng_ustconsumer_data_pending(struct lttng_consumer_stream *stream)
+{
+       int ret;
+
+       assert(stream);
+
+       DBG("UST consumer checking data pending");
+
+       ret = ustctl_get_next_subbuf(stream->chan->handle, stream->buf);
+       if (ret == 0) {
+               /* There is still data so let's put back this subbuffer. */
+               ret = ustctl_put_subbuf(stream->chan->handle, stream->buf);
+               assert(ret == 0);
+               ret = 1;  /* Data is pending */
+               goto end;
+       }
+
+       /* Data is NOT pending so ready to be read. */
+       ret = 0;
+
+end:
+       return ret;
+}