/*
 *  getopt.c - my re-implementation of getopt.
 *  Copyright 1997, 2000, 2001, 2002, 2006, Benjamin Sittler
 *
 *  Permission is hereby granted, free of charge, to any person
 *  obtaining a copy of this software and associated documentation
 *  files (the "Software"), to deal in the Software without
 *  restriction, including without limitation the rights to use, copy,
 *  modify, merge, publish, distribute, sublicense, and/or sell copies
 *  of the Software, and to permit persons to whom the Software is
 *  furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice shall be
 *  included in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *  NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 *  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 *  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 *  DEALINGS IN THE SOFTWARE.
 */

#if HAVE_CONFIG_H
#include "clamav-config.h"
#endif

#include <sys/types.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "getopt.h"

int optind = 1, opterr = 1, optopt = 0;
char *optarg = 0;

/* reset argument parser to start-up values */
/*
int getopt_reset(void)
{
    optind = 1;
    opterr = 1;
    optopt = 0;
    optarg = 0;
    return 0;
}
*/

/* this is the plain old UNIX getopt, with GNU-style extensions. */
/* if you're porting some piece of UNIX software, this is all you need. */
/* this supports GNU-style permutation and optional arguments */

int my_getopt(int argc, char *argvc[], const char *opts)
{
    char **argv        = (char **)argvc;
    static int charind = 0;
    const char *s;
    char mode, colon_mode;
    int off = 0, opt = -1;

    if (getenv("POSIXLY_CORRECT"))
        colon_mode = mode = '+';
    else {
        if ((colon_mode = *opts) == ':') off++;
        if (((mode = opts[off]) == '+') || (mode == '-')) {
            off++;
            if ((colon_mode != ':') && ((colon_mode = opts[off]) == ':'))
                off++;
        }
    }
    optarg = 0;
    if (charind) {
        optopt = argv[optind][charind];
        for (s = opts + off; *s; s++)
            if (optopt == *s) {
                charind++;
                if ((*(++s) == ':') || ((optopt == 'W') && (*s == ';'))) {
                    if (argv[optind][charind]) {
                        optarg  = &(argv[optind++][charind]);
                        charind = 0;
                    } else if (*(++s) != ':') {
                        charind = 0;
                        if (++optind >= argc) {
                            if (opterr) fprintf(stderr,
                                                "%s: option requires an argument -- %c\n",
                                                argv[0], optopt);
                            opt = (colon_mode == ':') ? ':' : '?';
                            goto getopt_ok;
                        }
                        optarg = argv[optind++];
                    }
                }
                opt = optopt;
                goto getopt_ok;
            }
        if (opterr) fprintf(stderr,
                            "%s: illegal option -- %c\n",
                            argv[0], optopt);
        opt = '?';
        if (argv[optind][++charind] == '\0') {
            optind++;
            charind = 0;
        }
    getopt_ok:
        if (charind && !argv[optind][charind]) {
            optind++;
            charind = 0;
        }
    } else if ((optind >= argc) ||
               ((argv[optind][0] == '-') &&
                (argv[optind][1] == '-') &&
                (argv[optind][2] == '\0'))) {
        optind++;
        opt = -1;
    } else if ((argv[optind][0] != '-') ||
               (argv[optind][1] == '\0')) {
        char *tmp;
        int i, j, k;

        if (mode == '+')
            opt = -1;
        else if (mode == '-') {
            optarg  = argv[optind++];
            charind = 0;
            opt     = 1;
        } else {
            for (i = j = optind; i < argc; i++)
                if ((argv[i][0] == '-') &&
                    (argv[i][1] != '\0')) {
                    optind = i;
                    opt    = my_getopt(argc, argv, opts);
                    while (i > j) {
                        tmp = argv[--i];
                        for (k = i; k + 1 < optind; k++) argv[k] = argv[k + 1];
                        argv[--optind] = tmp;
                    }
                    break;
                }
            if (i == argc) opt = -1;
        }
    } else {
        charind++;
        opt = my_getopt(argc, argv, opts);
    }
    if (optind > argc) optind = argc;
    return opt;
}

/* this is the extended getopt_long{,_only}, with some GNU-like
 * extensions. Implements _getopt_internal in case any programs
 * expecting GNU libc getopt call it.
 */

static int _getopt_internal(int argc, char *argv[], const char *shortopts,
                            const struct option *longopts, int *longind,
                            int long_only)
{
    char mode, colon_mode;
    int shortoff = 0, opt = -1;

    if (getenv("POSIXLY_CORRECT")) {
        colon_mode = mode = '+';
    } else {
        if ((colon_mode = *shortopts) == ':') shortoff++;
        if (((mode = shortopts[shortoff]) == '+') || (mode == '-')) {
            shortoff++;
            if ((colon_mode != ':') && ((colon_mode = shortopts[shortoff]) == ':'))
                shortoff++;
        }
    }
    optarg = 0;
    if ((optind >= argc) ||
        ((argv[optind][0] == '-') &&
         (argv[optind][1] == '-') &&
         (argv[optind][2] == '\0'))) {
        optind++;
        opt = -1;
    } else if ((argv[optind][0] != '-') ||
               (argv[optind][1] == '\0')) {
        char *tmp;
        int i, j, k;

        opt = -1;
        if (mode == '+')
            return -1;
        else if (mode == '-') {
            optarg = argv[optind++];
            return 1;
        }
        for (i = j = optind; i < argc; i++)
            if ((argv[i][0] == '-') &&
                (argv[i][1] != '\0')) {
                optind = i;

                opt = _getopt_internal(argc, argv, shortopts,
                                       longopts, longind,
                                       long_only);
                while (i > j) {
                    tmp = argv[--i];
                    for (k = i; k + 1 < optind; k++)
                        argv[k] = argv[k + 1];
                    argv[--optind] = tmp;
                }
                break;
            }
    } else if ((!long_only) && (argv[optind][1] != '-'))
        opt = my_getopt(argc, argv, shortopts);
    else {
        int charind, offset;
        int found = 0, ind, hits = 0;

        if (((optopt = argv[optind][1]) != '-') && !argv[optind][2]) {
            int c;

            ind = shortoff;
            while ((c = shortopts[ind++])) {
                if (((shortopts[ind] == ':') ||
                     ((c == 'W') && (shortopts[ind] == ';'))) &&
                    (shortopts[++ind] == ':'))
                    ind++;
                if (optopt == c) return my_getopt(argc, argv, shortopts);
            }
        }
        offset = 2 - (argv[optind][1] != '-');
        for (charind = offset;
             (argv[optind][charind] != '\0') &&
             (argv[optind][charind] != '=');
             charind++)
            ;
        for (ind = 0; longopts[ind].name && !hits; ind++)
            if ((strlen(longopts[ind].name) == (size_t)(charind - offset)) &&
                (strncmp(longopts[ind].name,
                         argv[optind] + offset, charind - offset) == 0))
                found = ind, hits++;
        if (!hits)
            for (ind = 0; longopts[ind].name; ind++)
                if (strncmp(longopts[ind].name,
                            argv[optind] + offset, charind - offset) == 0)
                    found = ind, hits++;
        if (hits == 1) {
            opt = 0;

            if (argv[optind][charind] == '=') {
                if (longopts[found].has_arg == 0) {
                    opt = '?';
                    if (opterr) fprintf(stderr,
                                        "%s: option `--%s' doesn't allow an argument\n",
                                        argv[0], longopts[found].name);
                } else {
                    optarg = argv[optind] + ++charind;
                    // charind = 0; // Never used again past here
                }
            } else if (longopts[found].has_arg == 1) {
                if (++optind >= argc) {
                    opt = (colon_mode == ':') ? ':' : '?';
                    if (opterr) fprintf(stderr,
                                        "%s: option `--%s' requires an argument\n",
                                        argv[0], longopts[found].name);
                } else
                    optarg = argv[optind];
            }
            if (!opt) {
                if (longind) *longind = found;
                if (!longopts[found].flag)
                    opt = longopts[found].val;
                else
                    *(longopts[found].flag) = longopts[found].val;
            }
            optind++;
        } else if (!hits) {
            if (offset == 1)
                opt = my_getopt(argc, argv, shortopts);
            else {
                opt = '?';
                if (opterr) fprintf(stderr,
                                    "%s: unrecognized option `%s'\n",
                                    argv[0], argv[optind++]);
            }
        } else {
            opt = '?';
            if (opterr) fprintf(stderr,
                                "%s: option `%s' is ambiguous\n",
                                argv[0], argv[optind++]);
        }
    }
    if (optind > argc) optind = argc;
    return opt;
}

int my_getopt_long(int argc, char *argv[], const char *shortopts,
                   const struct option *longopts, int *longind)
{
    return _getopt_internal(argc, argv, shortopts, longopts, longind, 0);
}

int my_getopt_long_only(int argc, char *argv[], const char *shortopts,
                        const struct option *longopts, int *longind)
{
    return _getopt_internal(argc, argv, shortopts, longopts, longind, 1);
}
