Re: [PATCH] perf kvm: introduce --list-cmds for use by scripts

[Jiri Olsa <jolsa@redhat.com>]

On Mon, Mar 03, 2014 at 08:26:36PM -0500, Ramkumar Ramachandra wrote:
> Introduce
> 
>   $ perf kvm --list-cmds
> 
> to dump a raw list of commands for use by the completion script. In
> order to do this, introduce parse_options_subcommand() for handling
> subcommands as a special case in the parse-options machinery.

so this doesn't change the behaviour at all, right?

SNIP

>  
> -	argc = parse_options(argc, argv, kvm_options, kvm_usage,
> -			PARSE_OPT_STOP_AT_NON_OPTION);
> +	argc = parse_options_subcommand(argc, argv, kvm_options, kvm_subcommands, kvm_usage,
> +					PARSE_OPT_STOP_AT_NON_OPTION);
>  	if (!argc)
>  		usage_with_options(kvm_usage, kvm_options);
>  
> diff --git a/tools/perf/perf-completion.sh b/tools/perf/perf-completion.sh
> index 496e2ab..ae3a576 100644
> --- a/tools/perf/perf-completion.sh
> +++ b/tools/perf/perf-completion.sh
> @@ -123,7 +123,7 @@ __perf_main ()
>  		__perfcomp_colon "$evts" "$cur"
>  	# List subcommands for 'perf kvm'
>  	elif [[ $prev == "kvm" ]]; then
> -		subcmds="top record report diff buildid-list stat"
> +		subcmds=$($cmd $prev --list-cmds)

Do we want some generic approach here.. if we're
adding generic --list-cmds option anyway.. hm?

SNIP

> -int parse_options(int argc, const char **argv, const struct option *options,
> -		  const char * const usagestr[], int flags)
> +int parse_options_subcommand(int argc, const char **argv, const struct option *options,
> +			const char *const subcommands[], const char *usagestr[], int flags)
>  {
>  	struct parse_opt_ctx_t ctx;
>  
>  	perf_header__set_cmdline(argc, argv);
>  
> +	/* build usage string if it's not provided */
> +	if (subcommands && !usagestr[0]) {
> +		struct strbuf buf = STRBUF_INIT;
> +
> +		strbuf_addf(&buf, "perf %s [<options>] {", argv[0]);
> +		for (int i = 0; subcommands[i]; i++) {
> +			if (i)
> +				strbuf_addstr(&buf, "|");
> +			strbuf_addstr(&buf, subcommands[i]);
> +		}
> +		strbuf_addstr(&buf, "}");
> +
> +		usagestr[0] = strdup(buf.buf);
> +		strbuf_release(&buf);
> +	}

is above code ever used now?

jirka