From c8fd9d119dc98ef4785b4d7204939a8a259f67e2 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Thu, 5 Dec 2019 01:58:09 -0500 Subject: [PATCH] Fix: lttng-live format: do not error out on empty streams hang up MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Attaching to a stream hung up before providing any trace packet causes ctf_open_mmap_stream_read() to return an error. This kind of scenario can happen with the upcoming "lttng clear" feature. Signed-off-by: Mathieu Desnoyers Signed-off-by: Jérémie Galarneau --- formats/ctf/ctf.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/formats/ctf/ctf.c b/formats/ctf/ctf.c index 980ebc9a..1ba9017f 100644 --- a/formats/ctf/ctf.c +++ b/formats/ctf/ctf.c @@ -2571,8 +2571,13 @@ int ctf_open_mmap_stream_read(struct ctf_trace *td, } ret = prepare_mmap_stream_definition(td, file_stream, packet_seek); - if (ret) + if (ret) { + /* We need to check for EOF here for empty files. */ + if (unlikely(file_stream->pos.offset == EOF)) { + ret = 0; + } goto error_index; + } /* * For now, only a single clock per trace is supported. -- 2.34.1