[lttng-dev] [PATCH babletrace 1.3/1.4] Fix: segmentation fault with multi-trace having non-correlated clocks

[Mathieu Desnoyers]

This bugfix is extracted from commit

commit 61cf588beae752e5ddfc60b6b5310f769ac9e852
Author: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
Date:   Tue Feb 9 13:27:24 2016 -0500

    Handle negative time and offset from Epoch

Which was fixing this issue, amongst other things.

[ This fix should be applied to Babeltrace stable 1.3 and 1.4 only. ]

Fixes: #790

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
---
 lib/context.c | 72 ++++++++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 49 insertions(+), 23 deletions(-)

diff --git a/lib/context.c b/lib/context.c
index 45aab34..7774ccd 100644
--- a/lib/context.c
+++ b/lib/context.c
@@ -115,7 +115,7 @@ int bt_context_add_trace(struct bt_context *ctx, const char *path,
 		fprintf(stderr, "[error] [Context] Creating trace handle %s .\n\n",
 				path);
 		ret = -1;
-		goto error;
+		goto error_close;
 	}
 	handle->format = fmt;
 	handle->td = td;
@@ -124,41 +124,67 @@ int bt_context_add_trace(struct bt_context *ctx, const char *path,
 		handle->path[PATH_MAX - 1] = '\0';
 	}
 
+	ret = bt_trace_collection_add(ctx->tc, td);
+	if (ret != 0)
+		goto error_destroy_handle;
+
 	if (fmt->set_handle)
 		fmt->set_handle(td, handle);
 	if (fmt->set_context)
 		fmt->set_context(td, ctx);
 
-	/* Add new handle to container */
-	g_hash_table_insert(ctx->trace_handles,
-		(gpointer) (unsigned long) handle->id,
-		handle);
-	ret = bt_trace_collection_add(ctx->tc, td);
-	if (ret != 0)
-		goto error;
-
 	if (fmt->convert_index_timestamp) {
 		ret = fmt->convert_index_timestamp(td);
 		if (ret < 0)
-			goto error;
+			goto error_collection_del;
+	}
+
+	if (fmt->timestamp_begin) {
+		handle->real_timestamp_begin =
+			fmt->timestamp_begin(td, handle, BT_CLOCK_REAL);
+		if (handle->real_timestamp_begin == -1ULL) {
+			ret = -1;
+			goto error_collection_del;
+		}
+	}
+	if (fmt->timestamp_end) {
+		handle->real_timestamp_end =
+			fmt->timestamp_end(td, handle, BT_CLOCK_REAL);
+		if (handle->real_timestamp_end == -1ULL) {
+			ret = -1;
+			goto error_collection_del;
+		}
+	}
+	if (fmt->timestamp_begin) {
+		handle->cycles_timestamp_begin =
+			fmt->timestamp_begin(td, handle, BT_CLOCK_CYCLES);
+		if (handle->cycles_timestamp_begin == -1ULL) {
+			ret = -1;
+			goto error_collection_del;
+		}
+	}
+	if (fmt->timestamp_end) {
+		handle->cycles_timestamp_end =
+			fmt->timestamp_end(td, handle, BT_CLOCK_CYCLES);
+		if (handle->cycles_timestamp_end == -1ULL) {
+			ret = -1;
+			goto error_collection_del;
+		}
 	}
 
-	if (fmt->timestamp_begin)
-		handle->real_timestamp_begin = fmt->timestamp_begin(td,
-				handle, BT_CLOCK_REAL);
-	if (fmt->timestamp_end)
-		handle->real_timestamp_end = fmt->timestamp_end(td, handle,
-				BT_CLOCK_REAL);
-	if (fmt->timestamp_begin)
-		handle->cycles_timestamp_begin = fmt->timestamp_begin(td,
-				handle, BT_CLOCK_CYCLES);
-	if (fmt->timestamp_end)
-		handle->cycles_timestamp_end = fmt->timestamp_end(td, handle,
-				BT_CLOCK_CYCLES);
+	/* Add new handle to container */
+	g_hash_table_insert(ctx->trace_handles,
+		(gpointer) (unsigned long) handle->id,
+		handle);
 
 	return handle->id;
 
-error:
+error_collection_del:
+	/* Remove from containers */
+	bt_trace_collection_remove(handle->td->ctx->tc, handle->td);
+error_destroy_handle:
+	bt_trace_handle_destroy(handle);
+error_close:
 	closeret = fmt->close_trace(td);
 	if (closeret) {
 		fprintf(stderr, "Error in close_trace callback\n");
-- 
2.1.4