/*
 * getopt_long() -- long options parser
 *
 * Portions Copyright (c) 1987, 1993, 1994
 * The Regents of the University of California.  All rights reserved.
 *
 * Portions Copyright (c) 2003
 * PostgreSQL Global Development Group
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "getopt.h"

#include <stdio.h>
#include <string.h>

#define BADCH '?'
#define BADARG ':'
#define EMSG ""

int opterr = 1, /* if error message should be printed */
    optind = 1, /* index into parent argv vector */
    optopt, /* character checked for validity */
    optreset; /* reset getopt */
char* optarg; /* argument associated with option */

int getopt_long(
    int argc,
    char* const argv[],
    const char* optstring,
    const struct option* longopts,
    int* longindex) {
  static const char* place = EMSG; /* option letter processing */
  const char* oli; /* option letter list index */

  if (!*place) { /* update scanning pointer */
    if (optind >= argc) {
      place = EMSG;
      return -1;
    }

    place = argv[optind];

    if (place[0] != '-') {
      place = EMSG;
      return -1;
    }

    place++;

    if (place[0] && place[0] == '-' && place[1] == '\0') { /* found "--" */
      ++optind;
      place = EMSG;
      return -1;
    }

    if (place[0] && place[0] == '-' && place[1]) {
      /* long option */
      size_t namelen;
      int i;

      place++;

      namelen = strcspn(place, "=");
      for (i = 0; longopts[i].name != NULL; i++) {
        if (strlen(longopts[i].name) == namelen &&
            strncmp(place, longopts[i].name, namelen) == 0) {
          if (longopts[i].has_arg) {
            if (place[namelen] == '=')
              optarg = (char*)place + namelen + 1;
            else if (optind < argc - 1) {
              optind++;
              optarg = argv[optind];
            } else {
              if (optstring[0] == ':')
                return BADARG;
              if (opterr)
                fprintf(
                    stderr,
                    "%s: option requires an argument -- %s\n",
                    argv[0],
                    place);
              place = EMSG;
              optind++;
              return BADCH;
            }
          } else {
            optarg = NULL;
            if (place[namelen] != 0) {
              /* XXX error? */
            }
          }

          optind++;

          if (longindex)
            *longindex = i;

          place = EMSG;

          if (longopts[i].flag == NULL)
            return longopts[i].val;
          else {
            *longopts[i].flag = longopts[i].val;
            return 0;
          }
        }
      }

      if (opterr && optstring[0] != ':')
        fprintf(stderr, "%s: illegal option -- %s\n", argv[0], place);
      place = EMSG;
      optind++;
      return BADCH;
    }
  }

  /* short option */
  optopt = (int)*place++;

  oli = strchr(optstring, optopt);
  if (!oli) {
    if (!*place)
      ++optind;
    if (opterr && *optstring != ':')
      fprintf(stderr, "%s: illegal option -- %c\n", argv[0], optopt);
    return BADCH;
  }

  if (oli[1] != ':') { /* don't need argument */
    optarg = NULL;
    if (!*place)
      ++optind;
  } else { /* need an argument */
    if (*place) /* no white space */
      optarg = (char*)place;
    else if (argc <= ++optind) { /* no arg */
      place = EMSG;
      if (*optstring == ':')
        return BADARG;
      if (opterr)
        fprintf(
            stderr, "%s: option requires an argument -- %c\n", argv[0], optopt);
      return BADCH;
    } else
      /* white space */
      optarg = argv[optind];
    place = EMSG;
    ++optind;
  }
  return optopt;
}
