/* Argp example #4 -- a program with somewhat more complicated options */

/* This program uses the same features as example 3, but has more options,
   and somewhat more structure in the -help output.  It also shows how you
   can `steal' the remainder of the input arguments past a certain point, for
   programs that accept a list of items.  It also shows the special argp KEY
   value ARGP_KEY_NO_ARGS, which is only given if no non-option arguments
   were supplied to the program.

   For structuring the help output, two features are used, *headers* which
   are entries in the options vector with the first four fields being zero,
   and a two part documentation string (in the variable DOC), which allows
   documentation both before and after the options; the two parts of DOC are
   separated by a vertical-tab character ('\v', or '\013').  By convention,
   the documentation before the options is just a short string saying what
   the program does, and that afterwards is longer, describing the behavior
   in more detail.  All documentation strings are automatically filled for
   output, although newlines may be included to force a line break at a
   particular point.  All documenation strings are also passed to the
   `gettext' function, for possible translation into the current locale.  */

#include <stdlib.h>
/* #include <error.h> */
#include <argp.h>

const char *argp_program_version = "argp-ex4 1.0";
const char *argp_program_bug_address = "<bug-gnu-utils@prep.ai.mit.edu>";

static char doc[] =
  "Argp example #4 -- a program with somewhat more complicated options\
\vThis part of the documentation comes *after* the options; note that\
 it is automatically filled, but it's possible to force a line-break,\
 e.g.\n<-- here.";
static char args_doc[] = "ARG1 [STRING...]";

/* Keys for options without short-options.  */
#define OPT_ABORT  1		/* --abort */

static struct argp_option options[] = {
  {"verbose",  'v', 0,       0, "Produce verbose output" },
  {"quiet",    'q', 0,       0, "Don't produce any output" },
  {"silent",   's', 0,       OPTION_ALIAS },
  {"output",   'o', "FILE",  0, "Output to FILE instead of standard output" },

  {0, 0, 0, 0, "The following options should be grouped together:" },
  {"repeat",   'r', "COUNT", OPTION_ARG_OPTIONAL,
   "Repeat the output COUNT (default 10) times"},
  {"abort",    OPT_ABORT, 0, 0, "Abort before showing any output"}, 
  { 0 }
};

/* Used by main to communicate with parse_opt.  */
struct arguments
{
  char *arg1;			/* ARG1 */
  char **strings;		/* [STRING...] */
  int silent, verbose, abort;	/* -s, -v, --abort */
  char *output_file;		/* --output=FILE */
  int repeat_count;		/* --repeat[=COUNT] */
};

static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
  /* Get the INPUT argument from argp_parse, which we know is a pointer to
     our arguments structure.  */
  struct arguments *arguments = state->input;

  switch (key)
    {
    case 'q': case 's':
      arguments->silent = 1;
      break;
    case 'v':
      arguments->verbose = 1;
      break;
    case 'o':
      arguments->output_file = arg;
      break;
    case 'r':
      arguments->repeat_count = arg ? atoi (arg) : 10;
      break;
    case OPT_ABORT:
      arguments->abort = 1;
      break;

    case ARGP_KEY_NO_ARGS:
      argp_usage (state);

    case ARGP_KEY_ARG:
      /* Here we know that STATE->arg_num == 0, since we force argument
	 parsing to end before any more arguments can get here.  */
      arguments->arg1 = arg;

      /* Now we consume all the rest of the arguments.  STATE->next is the
	 index in STATE->argv of the next argument to be parsed, which is the
	 first STRING we're interested in, so we can just use
	 `&state->argv[state->next]' as the value for arguments->strings.

	 IN ADDITION, by setting STATE->next to the end of the arguments, we
	 can force argp to stop parsing here and return.  */
      arguments->strings = &state->argv[state->next];
      state->next = state->argc;

      break;

    default:
      return ARGP_ERR_UNKNOWN;
    }
  return 0;
}

static struct argp argp = { options, parse_opt, args_doc, doc };

int main (int argc, char **argv)
{
  int i, j;
  struct arguments arguments;

  /* Default values.  */
  arguments.silent = 0;
  arguments.verbose = 0;
  arguments.output_file = "-";
  arguments.repeat_count = 1;
  arguments.abort = 0;

  argp_parse (&argp, argc, argv, 0, 0, &arguments);

  if (arguments.abort)
    {
      fprintf (stderr, "ABORTED");
      exit (-1);
    }

  for (i = 0; i < arguments.repeat_count; i++)
    {
      printf ("ARG1 = %s\n", arguments.arg1);
      printf ("STRINGS = ");
      for (j = 0; arguments.strings[j]; j++)
	printf (j == 0 ? "%s" : ", %s", arguments.strings[j]);
      printf ("\n");
      printf ("OUTPUT_FILE = %s\nVERBOSE = %s\nSILENT = %s\n",
	      arguments.output_file,
	      arguments.verbose ? "yes" : "no",
	      arguments.silent ? "yes" : "no");
    }

  exit (0);
}
