15670430创建于 2020年12月28日历史提交
/*
 * 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.
 *
 * src/port/getopt_long.c
 */

#include "c.h"

#include "getopt_long.h"

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

/*
 * getopt_long
 *	Parse argc/argv argument vector, with long options.
 *
 * This implementation does not use optreset.  Instead, we guarantee that
 * it can be restarted on a new argv array after a previous call returned -1,
 * if the caller resets optind to 1 before the first call of the new series.
 * (Internally, this means we must be sure to reset "place" to EMSG before
 * returning -1.)
 */
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 */
#ifdef WIN32
    const char* oli = NULL; /* option letter list index */
#else
    char* oli = NULL; /* option letter list index */
#endif
    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;
                    }

                    optind++;

                    if (longindex != NULL) {
                        *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((char*)optstring, optopt);
    if (oli == NULL) {
        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;
}