X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=formats%2Flttng-live%2Flttng-live-comm.c;h=945df4317bdec9d0ca1aa324405f110d229d8143;hb=f312b3aa35382b62e9f8bd2c4cbdd9180490845e;hp=785f5f37022609a702cddf3341e20b32611d0d1c;hpb=b7e8a8e17de9b9e5b717d8b664b8385a2562aee8;p=babeltrace.git

diff --git a/formats/lttng-live/lttng-live-comm.c b/formats/lttng-live/lttng-live-comm.c
index 785f5f37..945df431 100644
--- a/formats/lttng-live/lttng-live-comm.c
+++ b/formats/lttng-live/lttng-live-comm.c
@@ -33,6 +33,7 @@
 #include <inttypes.h>
 #include <fcntl.h>
 #include <sys/mman.h>
+#include <poll.h>
 
 #include <babeltrace/ctf/ctf-index.h>
 
@@ -54,6 +55,8 @@
 #include "lttng-live.h"
 #include "lttng-viewer-abi.h"
 
+#define ACTIVE_POLL_DELAY	100	/* ms */
+
 /*
  * Memory allocation zeroed
  */
@@ -586,10 +589,12 @@ int append_metadata(struct lttng_live_ctx *ctx,
 	ret = ctf_append_trace_metadata(
 			viewer_stream->ctf_trace->handle->td,
 			metadata->ctf_trace->metadata_fp);
-	if (ret != 0) {
+	/* We accept empty metadata packets */
+	if (ret != 0 && ret != -ENOENT) {
 		fprintf(stderr, "[error] Appending metadata\n");
 		goto error;
 	}
+	ret = 0;
 
 error:
 	return ret;
@@ -671,15 +676,19 @@ retry:
 			ret = append_metadata(ctx, stream);
 			if (ret)
 				goto error;
-			goto retry;
 		}
 		if (rp.flags & LTTNG_VIEWER_FLAG_NEW_STREAM) {
+			printf_verbose("get_data_packet: new streams needed\n");
 			ret = ask_new_streams(ctx);
 			if (ret < 0)
 				goto error;
 			g_hash_table_foreach(ctx->session->ctf_traces, add_traces,
 					ctx->bt_ctx);
 		}
+		if (rp.flags & (LTTNG_VIEWER_FLAG_NEW_METADATA
+				| LTTNG_VIEWER_FLAG_NEW_STREAM)) {
+			goto retry;
+		}
 		fprintf(stderr, "[error] get_data_packet: error\n");
 		ret = -1;
 		goto end;
@@ -740,7 +749,7 @@ retry:
 		goto error;
 	}
 	assert(ret_len == len);
-
+	ret = 0;
 end:
 error:
 	return ret;
@@ -869,7 +878,7 @@ int get_new_metadata(struct lttng_live_ctx *ctx,
 {
 	int ret = 0;
 	struct lttng_live_viewer_stream *metadata_stream;
-	size_t size;
+	size_t size, len_read = 0;;
 
 	metadata_stream = viewer_stream->ctf_trace->metadata_stream;
 	if (!metadata_stream) {
@@ -890,7 +899,13 @@ int get_new_metadata(struct lttng_live_ctx *ctx,
 		 * negative value on error.
 		 */
 		ret = get_one_metadata_packet(ctx, metadata_stream);
-	} while (ret > 0);
+		if (ret > 0) {
+			len_read += ret;
+		}
+		if (!len_read) {
+			(void) poll(NULL, 0, ACTIVE_POLL_DELAY);
+		}
+	} while (ret > 0 || !len_read);
 
 	if (fclose(metadata_stream->metadata_fp_write))
 		perror("fclose");
@@ -986,7 +1001,7 @@ retry:
 		break;
 	case LTTNG_VIEWER_INDEX_RETRY:
 		printf_verbose("get_next_index: retry\n");
-		sleep(1);
+		(void) poll(NULL, 0, ACTIVE_POLL_DELAY);
 		goto retry;
 	case LTTNG_VIEWER_INDEX_HUP:
 		printf_verbose("get_next_index: stream hung up\n");
@@ -1485,6 +1500,8 @@ void lttng_live_read(struct lttng_live_ctx *ctx)
 			ret = ask_new_streams(ctx);
 			if (ret < 0)
 				goto end_free;
+			if (!ctx->session->stream_count)
+				(void) poll(NULL, 0, ACTIVE_POLL_DELAY);
 		}
 
 		g_hash_table_foreach(ctx->session->ctf_traces, add_traces,