Re: [PATCH 2/2] trace-cmd: Add new API tracecmd_open_head()

[Steven Rostedt <rostedt@goodmis.org>]

On Thu,  9 Apr 2020 16:28:25 +0300
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:

> Add an API to create a tracecmd_handle from a file,
> read and parse only the trace headers from the file.
> This allows to implement opening a trace file on
> stages - reading the trace headers and reading the trace data.
> 
> Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
> ---
>  include/trace-cmd/trace-cmd.h |  1 +
>  lib/trace-cmd/trace-input.c   | 28 ++++++++++++++++++++++++++++
>  2 files changed, 29 insertions(+)
> 
> diff --git a/include/trace-cmd/trace-cmd.h b/include/trace-cmd/trace-cmd.h
> index 3f96bbde..e22aa251 100644
> --- a/include/trace-cmd/trace-cmd.h
> +++ b/include/trace-cmd/trace-cmd.h
> @@ -143,6 +143,7 @@ typedef void (*tracecmd_handle_init_func)(struct tracecmd_input *handle,
>  struct tracecmd_input *tracecmd_alloc(const char *file);
>  struct tracecmd_input *tracecmd_alloc_fd(int fd);
>  struct tracecmd_input *tracecmd_open(const char *file);
> +struct tracecmd_input *tracecmd_open_head(const char *file);
>  struct tracecmd_input *tracecmd_open_fd(int fd);
>  void tracecmd_ref(struct tracecmd_input *handle);
>  void tracecmd_close(struct tracecmd_input *handle);

Hi Tzvetomir,

I was thinking, before we release libtracecmd, we should add
tracecmd_open() and tracecmd_open_fd() to the library. Just because I find
that tracecmd_open_head() is a awkward name to have alone and only makes
sense if there's already a tracecmd_open(). It will also help with
differentiating the different functions.

I know we were going to only have functions that kernelshark uses, but that
may be a little too limiting.

Thanks!

-- Steve