Re: [PATCH v2 8/8] trace-cmd: Add new function to set log level

[Steven Rostedt <rostedt@goodmis.org>]

On Fri,  7 May 2021 12:53:33 +0300
"Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote:

> Introduce a new trace-cmd internal function to set the application log
> level.
>  trace_set_verbose()
> The log level can be set using string with log id or log name.
> 
> Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
> ---
>  tracecmd/include/trace-local.h |  2 ++
>  tracecmd/trace-cmd.c           | 41 ++++++++++++++++++++++++++++++++++
>  2 files changed, 43 insertions(+)
> 
> diff --git a/tracecmd/include/trace-local.h b/tracecmd/include/trace-local.h
> index b3997d00..8da07c83 100644
> --- a/tracecmd/include/trace-local.h
> +++ b/tracecmd/include/trace-local.h
> @@ -39,6 +39,8 @@ void usage(char **argv);
>  extern int silence_warnings;
>  extern int show_status;
>  
> +int trace_set_verbose(char *level);
> +
>  struct pid_record_data {
>  	int			pid;
>  	int			brass[2];
> diff --git a/tracecmd/trace-cmd.c b/tracecmd/trace-cmd.c
> index 60cd3ea1..4e4a73af 100644
> --- a/tracecmd/trace-cmd.c
> +++ b/tracecmd/trace-cmd.c
> @@ -45,6 +45,47 @@ void *malloc_or_die(unsigned int size)
>  	return data;
>  }
>  
> +static struct trace_log_severity {
> +	int		id;
> +	const char	*name;
> +} log_severtity[] = {

Is there a reason for the extra 't' in severity?

> +	{ .id = TEP_LOG_NONE, .name = "none" },
> +	{ .id = TEP_LOG_CRITICAL, .name = "crit" },
> +	{ .id = TEP_LOG_ERROR, .name = "err" },
> +	{ .id = TEP_LOG_WARNING, .name = "warn" },
> +	{ .id = TEP_LOG_INFO, .name = "info" },
> +	{ .id = TEP_LOG_DEBUG, .name = "debug" },
> +	{ .id = TEP_LOG_ALL, .name = "all" },
> +};
> +
> +int trace_set_verbose(char *level)
> +{
> +	int id;
> +
> +	if (!level)
> +		return -1;
> +
> +	if (isdigit(level[0])) {
> +		id = atoi(level);
> +		if (id >= TEP_LOG_NONE && id <= TEP_LOG_ALL) {
> +			tracecmd_set_loglevel(id);
> +			return 0;
> +		}
> +	} else {
> +		int size = sizeof(log_severtity) / sizeof(log_severtity[0]);

This can be shortened to:

		int size = ARRAY_SIZE(log_severity);

Or at least we need to copy that macro to something that trace-cmd core has
access to (see lib/trace-cmd/include/private/trace-cmd-private.h)


> +		int i;
> +
> +		for (i = 0; i < size; i++) {
> +			if (strlen(level) >= strlen(log_severtity[i].name) &&

Why the strlen test? It's OK to pass in "debugignorme"? What's the use case
for this?

Anyway, I applied the first two patches of this series.

-- Steve


> +			    !strncmp(level, log_severtity[i].name, strlen(log_severtity[i].name))) {
> +				tracecmd_set_loglevel(log_severtity[i].id);
> +				return 0;
> +			}
> +		}
> +	}
> +
> +	return -1;
> +}
>  
>  /**
>   * struct command