[PATCH evemu 2/3] tools: play: use getopt

[Benjamin Tissoires]

On Thu, Jan 9, 2014 at 5:06 PM, Benjamin Tissoires
<benjamin.tissoires at gmail.com> wrote:
> On Thu, Jan 9, 2014 at 5:07 PM, Peter Hutterer <peter.hutterer at who-t.net> wrote:
>> On Thu, Jan 09, 2014 at 02:34:08PM -0500, Benjamin Tissoires wrote:
>>> Instead of relying on argc and hard coded values, use getopt framework.
>>>
>>> Signed-off-by: Benjamin Tissoires <benjamin.tissoires at gmail.com>
>>> ---
>>>  tools/evemu-play.c | 37 +++++++++++++++++++++++++++++++++----
>>>  1 file changed, 33 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/tools/evemu-play.c b/tools/evemu-play.c
>>> index 8d14618..030e142 100644
>>> --- a/tools/evemu-play.c
>>> +++ b/tools/evemu-play.c
>>> @@ -45,10 +45,18 @@
>>>  #include <fcntl.h>
>>>  #include <string.h>
>>>  #include <unistd.h>
>>> +#include <getopt.h>
>>> +
>>> +static struct option opts[] = {
>>> +     { "help", no_argument, 0, 'h'},
>>> +};
>>>
>>>  static void usage(void)
>>>  {
>>> -     fprintf(stderr, "Usage: %s <device>\n", program_invocation_short_name);
>>> +     fprintf(stderr, "Usage: %s [OPTION] <device>\n", program_invocation_short_name);
>>> +     fprintf(stderr, "\n");
>>> +     fprintf(stderr, "Where OPTION is:\n");
>>> +     fprintf(stderr, "   -h or --help: print this message\n");
>>>       fprintf(stderr, "\n");
>>>       fprintf(stderr, "Event data is read from standard input.\n");
>>>  }
>>> @@ -56,11 +64,30 @@ static void usage(void)
>>>  int main(int argc, char *argv[])
>>>  {
>>>       int fd;
>>> -     if (argc != 2) {
>>> +
>>> +     while(1) {
>>> +             int option_index = 0;
>>> +             int c;
>>> +
>>> +             c = getopt_long(argc, argv, "h", opts, &option_index);
>>
>> don't you need GNU_SOURCE for getopt_long or is that pulled in from
>> elsewhere?
>
> Yes, I need it... :(
> I bet I missed my split between patches 2 and 3...

Actually no. It was added in 1/3: tools: play: externalize usage() call

Cheers,
Benjamin

>
>
>> also, we could probably drop it from other files and use
>> AC_USE_SYSTEM_EXTENSIONS in configure.ac.
>
> will see what I can do.
>
>>
>>> +             if (c == -1) /* Detect the end of the options. */
>>> +                     break;
>>> +
>>> +             switch(c) {
>>> +                     case 'h': /* help */
>>> +                     default:
>>> +                             usage();
>>> +                             goto out;
>>> +             }
>>> +     }
>>> +
>>> +     /* if the device was not specified, fail */
>>> +     if (optind >= argc) {
>>>               usage();
>>> -             return -1;
>>> +             goto out;
>>>       }
>>> -     fd = open(argv[1], O_WRONLY);
>>> +
>>> +     fd = open(argv[optind], O_WRONLY);
>>>       if (fd < 0) {
>>>               fprintf(stderr, "error: could not open device\n");
>>>               return -1;
>>> @@ -70,4 +97,6 @@ int main(int argc, char *argv[])
>>>       }
>>>       close(fd);
>>>       return 0;
>>> +out:
>>> +     return -1;
>>
>> we should probably return 1 instead of -1 but that's a follow-up patch.
>
> probably :)
>
> Cheers,
> Benjamin