trace: Forbid event format ending with newline character
Event format ending with newlines confuse the trace reports.
Forbid them.
Add a check to refuse new format added with trailing newline:
$ make
[...]
GEN hw/misc/trace.h
Traceback (most recent call last):
File "scripts/tracetool.py", line 152, in <module>
main(sys.argv)
File "scripts/tracetool.py", line 143, in main
events.extend(tracetool.read_events(fh, arg))
File "scripts/tracetool/__init__.py", line 367, in read_events
event = Event.build(line)
File "scripts/tracetool/__init__.py", line 281, in build
raise ValueError("Event format can not end with a newline character")
ValueError: Error at hw/misc/trace-events:121: Event format can not end with a newline character
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190916095121.29506-3-philmd@redhat.com
Message-Id: <20190916095121.29506-3-philmd@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/docs/devel/tracing.txt b/docs/devel/tracing.txt
index 76e492a..8231bbf 100644
--- a/docs/devel/tracing.txt
+++ b/docs/devel/tracing.txt
@@ -112,6 +112,8 @@
Format strings should reflect the types defined in the trace event. Take
special care to use PRId64 and PRIu64 for int64_t and uint64_t types,
respectively. This ensures portability between 32- and 64-bit platforms.
+Format strings must not end with a newline character. It is the responsibility
+of backends to adapt line ending for proper logging.
Each event declaration will start with the event name, then its arguments,
finally a format string for pretty-printing. For example:
