Re: [PATCH v4 08/17] perf: util: add general function to parse sublevel options

[Namhyung Kim <namhyung@kernel.org>]

On Fri, Jul 10, 2020 at 10:44 PM Changbin Du <changbin.du@gmail.com> wrote:
>
> This factors out a general function perf_parse_sublevel_options() to parse
> sublevel options. The 'sublevel' options is something like the '--debug'
> options which allow more sublevel options.
>
> Signed-off-by: Changbin Du <changbin.du@gmail.com>
>
> ---
> v2: add util/parse-sublevel-options.c
> ---
[snip]
> diff --git a/tools/perf/util/parse-sublevel-options.c b/tools/perf/util/parse-sublevel-options.c
> new file mode 100644
> index 000000000000..39798568547c
> --- /dev/null
> +++ b/tools/perf/util/parse-sublevel-options.c
> @@ -0,0 +1,63 @@
> +#include <stdlib.h>
> +#include <stdint.h>
> +#include <string.h>
> +#include <stdio.h>
> +
> +#include "util/debug.h"
> +#include "util/parse-sublevel-options.h"
> +
> +static int parse_one_sublevel_option(const char *str,
> +                                    struct sublevel_option *opts)
> +{
> +       struct sublevel_option *opt = &opts[0];
> +       char *vstr, *s = strdup(str);
> +       int v = 1;

I know you just copied the code, but let's add a check for
the return value of strdup().

Also I think you can just use the opts pointer..


> +
> +       vstr = strchr(s, '=');
> +       if (vstr)
> +               *vstr++ = 0;
> +
> +       while (opt->name) {
> +               if (!strcmp(s, opt->name))
> +                       break;
> +               opt++;
> +       }
> +
> +       if (!opt->name) {
> +               pr_err("Unknown option name '%s'\n", s);
> +               free(s);
> +               return -1;
> +       }
> +
> +       if (vstr)
> +               v = atoi(vstr);
> +
> +       *opt->value_ptr = v;
> +       free(s);
> +       return 0;
> +}
> +
> +/* parse options like --foo a=<n>,b,c... */
> +int perf_parse_sublevel_options(const char *str, struct sublevel_option *opts)
> +{
> +       char *s = strdup(str);
> +       char *p = NULL;
> +       int ret;
> +
> +       if (!s)
> +               return -1;
> +
> +       p = strtok(s, ",");
> +       while (p) {
> +               ret = parse_one_sublevel_option(p, opts);
> +               if (ret) {
> +                       free(s);
> +                       return ret;
> +               }
> +
> +               p = strtok(NULL, ",");
> +       }
> +
> +       free(s);
> +       return 0;
> +}
> diff --git a/tools/perf/util/parse-sublevel-options.h b/tools/perf/util/parse-sublevel-options.h
> new file mode 100644
> index 000000000000..9b9efcc2aaad
> --- /dev/null
> +++ b/tools/perf/util/parse-sublevel-options.h
> @@ -0,0 +1,11 @@
> +#ifndef _PERF_PARSE_SUBLEVEL_OPTIONS_H
> +#define _PERF_PARSE_SUBLEVEL_OPTIONS_H
> +
> +struct sublevel_option {
> +       const char *name;
> +       int *value_ptr;
> +};
> +
> +int perf_parse_sublevel_options(const char *str, struct sublevel_option *opts);
> +
> +#endif
> \ No newline at end of file

Please add a newline at the end.

Thanks
Namhyung


> --
> 2.25.1
>