common/util/getoptstr.c

	getoptstr.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1992-1996,2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */


#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * This file contains getoptstr(), which is getopt() for strings of arguments
 * (not arrays of strings).  It is used by the bootloader ({*fs,inet}boot) and
 * the kernel to process argument strings.
 */


#include "getoptstr.h"


/*
 * This routine needs to be supplied by whatever uses this file.
 */
char *strchr(const char *s, int c);


#define NULL    ((void *)0)

#define ISNTWORDCH(c)   ((c) == '\0' || ISSPACE(c))


/*
 * Prepare a gos_params structure for use by getoptstr().
 */
void
getoptstr_init(struct gos_params *params)
{
    params->gos_pos = 1;
}

/*
 * Modeled after lib/libc/port/gen/getopt.c.
 *
 * With params->gos_opts set to a string of options and params->gos_strp set to
 * an argument string, getoptstr returns
 *   * the next option letter, where the options are given by the
 *     params->gos_opts string.  If the option is followed by a ':' in gos_opts,
 *     then params->gos_optargp will point to the beginning of the argument in
 *     the string, and params->gos_optarglen will contain its length.
 *   * -1 if "--" or a non-option argument is encountered.  In the former
 *     case, params->gos_strp is advanced to the next argument.
 *   * '?' if an illegal option is encountered or if an argument is not
 *     supplied for an option which requires one and ':' is not the first
 *     character of opts.  In both cases, the option letter is available in
 *     params->gos_last_opt, and in the former case, params->gos_errp will
 *     point to the offending character.
 *   * ':' if an argument is not supplied for an option which requires one and
 *     ':' is the first character of params->gos_opts.
 */
int
getoptstr(struct gos_params *params)
{
    char c;
    char *cp;

    /*
     * const because we should update params.  Just make sure you don't
     * use this after you update params->gos_strp.
     */
    const char * const strp = params->gos_strp;


    if (params->gos_opts == NULL || strp == NULL)
        return (-1);

    if (params->gos_pos == 1) {
        /* At beginning of new word. */

        if (strp[0] == '\0' || strp[0] != '-')
            return (-1);
        if (ISNTWORDCH(strp[1])) {
            /* Lone dash. */
            return (-1);
        }

        /* Check for "--" */
        if (strp[1] == '-' && ISNTWORDCH(strp[2])) {
            params->gos_strp = &strp[2];
            SKIP_SPC(params->gos_strp);
            return (-1);
        }
    }

    params->gos_last_opt = c = strp[params->gos_pos];
    if (c == ':' || (cp = strchr(params->gos_opts, c)) == NULL) {
        /* Unrecognized option error. */
        params->gos_errp = &strp[params->gos_pos];
        ++params->gos_pos;
        if (ISNTWORDCH(strp[params->gos_pos])) {
            params->gos_strp = &strp[params->gos_pos];
            SKIP_SPC(params->gos_strp);
            params->gos_pos = 1;
        }
        return ('?');
    }

    if (cp[1] == ':') {
        /* This option expects an argument. */

        params->gos_strp = &strp[params->gos_pos + 1];

        if (ISNTWORDCH(*params->gos_strp)) {
            /* The argument is in the next word. */
            SKIP_SPC(params->gos_strp);

            if (*params->gos_strp == '\0') {
                /* Not.  Missing argument. */
                params->gos_pos = 1;
                params->gos_optargp = NULL;
                return (params->gos_opts[0] == ':' ? ':' : '?');
            }
        }

        params->gos_optargp = params->gos_strp;

        /* Advance to the next word. */
        SKIP_WORD(params->gos_strp);
        params->gos_optarglen = params->gos_strp - params->gos_optargp;
        SKIP_SPC(params->gos_strp);

        params->gos_pos = 1;
    } else {
        ++params->gos_pos;
        if (ISNTWORDCH(strp[params->gos_pos])) {
            params->gos_strp = &strp[params->gos_pos];
            SKIP_SPC(params->gos_strp);
            params->gos_pos = 1;
        }
        params->gos_optargp = NULL;
    }
    return (c);
}