On 9/13/19 6:52 AM, Philippe Mathieu-Daudé wrote:
> 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
>
> Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
> ---
> docs/devel/tracing.txt | 2 ++
> scripts/tracetool/__init__.py | 3 +++
> 2 files changed, 5 insertions(+)
>
> diff --git a/docs/devel/tracing.txt b/docs/devel/tracing.txt
> index 76e492a489..8231bbf5d1 100644
> --- a/docs/devel/tracing.txt
> +++ b/docs/devel/tracing.txt
> @@ -112,6 +112,8 @@ Trace events should use types as follows:
> 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:
> diff --git a/scripts/tracetool/__init__.py b/scripts/tracetool/__init__.py
> index 6fca674936..57df74e67c 100644
> --- a/scripts/tracetool/__init__.py
> +++ b/scripts/tracetool/__init__.py
> @@ -277,6 +277,9 @@ class Event(object):
> if fmt.find("%m") != -1 or fmt_trans.find("%m") != -1:
> raise ValueError("Event format '%m' is forbidden, pass the error
> "
> "as an explicit trace argument")
> + if fmt.endswith("\\n\""):
> + raise ValueError("Event format must not end with a newline "
It's barely worth mentioning, but you can use r"\n" for cases like this,
if it makes it easier to read.
