form/common/regcmp.c

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


/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"    /* SVr4.0 1.2   */

/*LINTLIBRARY*/

#include <sys/types.h>
#include <stdlib.h>
#include "utility.h"

/* this code was taken from REGCMP(3X) */

#define SSIZE   16
#define TGRP    48
#define A256    02
#define ZERO    01
#define NBRA    10
#define CIRCFL  32;
#define SLOP    5
#define FEOF    0 /* This was originally EOF but it clashes with the header */
            /* definition so it was changed to FEOF */

#define CBRA    60
#define GRP 40
#define SGRP    56
#define PGRP    68
#define EGRP    44
#define RNGE    03
#define CCHR    20
#define CDOT    64
#define CCL 24
#define NCCL    8
#define CDOL    28
#define FCEOF   52 /* This was originally CEOF but it clashes with the header */
            /* definition so it was changed to FCEOF */
#define CKET    12

#define STAR    01
#define PLUS    02
#define MINUS   16

intptr_t    *__sp_;
intptr_t    *__stmax;
int __i_size;

/*ARGSUSED2*/
char *
libform_regcmp(char *cs1, char *cs2)
{
    char c;
    char *ep, *sp;
    int *adx;
    int i, cflg;
    char *lastep, *sep, *eptr;
    int nbra, ngrp;
    int cclcnt;
    intptr_t stack[SSIZE];

    __sp_ = stack;
    *__sp_ = -1;
    __stmax = &stack[SSIZE];

    adx = (int *)&cs1;
    i = nbra = ngrp = 0;
    while (*adx)
        i += __size((char *)(intptr_t)*adx++);
    adx = (int *)&cs1;
    sp = (char *)(intptr_t)*adx++;
    if ((sep = ep = malloc((unsigned)(2 * i + SLOP))) == NULL)
        return (NULL);
    if ((c = *sp++) == FEOF)
        goto cerror;
    if (c == '^') {
        c = *sp++;
        *ep++ = CIRCFL;
    }
    if ((c == '*') || (c == '+') || (c == '{'))
        goto cerror;
    sp--;
    for (;;) {
        if ((c = *sp++) == FEOF) {
            if (*adx) {
                sp = (char *)(intptr_t)*adx++;
                continue;
            }
            *ep++ = FCEOF;
            if (--nbra > NBRA || *__sp_ != -1)
                goto cerror;
            __i_size = (int) (ep - sep);
            return (sep);
        }
        if ((c != '*') && (c != '{') && (c != '+'))
            lastep = ep;
        switch (c) {

        case '(':
            if (!__rpush(ep)) goto cerror;
            *ep++ = CBRA;
            *ep++ = -1;
            continue;
        case ')':
            if (!(eptr = (char *)__rpop())) goto cerror;
            if ((c = *sp++) == '$') {
                if ('0' > (c = *sp++) || c > '9')
                    goto cerror;
                *ep++ = CKET;
                *ep++ = *++eptr = nbra++;
                *ep++ = (c-'0');
                continue;
            }
            *ep++ = EGRP;
            *ep++ = ngrp++;
            sp--;
            switch (c) {
            case '+':
                *eptr = PGRP;
                break;
            case '*':
                *eptr = SGRP;
                break;
            case '{':
                *eptr = TGRP;
                break;
            default:
                *eptr = GRP;
                continue;
            }
            i = (int) (ep - eptr - 2);
            for (cclcnt = 0; i >= 256; cclcnt++)
                i -= 256;
            if (cclcnt > 3) goto cerror;
            *eptr |= cclcnt;
            *++eptr = (char) i;
            continue;

        case '\\':
            *ep++ = CCHR;
            if ((c = *sp++) == FEOF)
                goto cerror;
            *ep++ = c;
            continue;

        case '{':
            *lastep |= RNGE;
            cflg = 0;
        nlim:
            if ((c = *sp++) == '}') goto cerror;
            i = 0;
            do {
                if ('0' <= c && c <= '9')
                    i = (i*10+(c-'0'));
                else goto cerror;
            } while (((c = *sp++) != '}') && (c != ','));
            if (i > 255) goto cerror;
            *ep++ = (char) i;
            if (c == ',') {
                if (cflg++) goto cerror;
                if ((c = *sp++) == '}') {
                    *ep++ = -1;
                    continue;
                } else {
                    sp--;
                    goto nlim;
                }
            }
            if (!cflg)
                *ep++ = (char) i;
            else if ((ep[-1]&0377) < (ep[-2]&0377))
                goto cerror;
            continue;

        case '.':
            *ep++ = CDOT;
            continue;

        case '+':
            if (*lastep == CBRA || *lastep == CKET)
                goto cerror;
            *lastep |= PLUS;
            continue;

        case '*':
            if (*lastep == CBRA || *lastep == CKET)
            goto cerror;
            *lastep |= STAR;
            continue;

        case '$':
            if ((*sp != FEOF) || (*adx))
                goto defchar;
            *ep++ = CDOL;
            continue;

        case '[':
            *ep++ = CCL;
            *ep++ = 0;
            cclcnt = 1;
            if ((c = *sp++) == '^') {
                c = *sp++;
                ep[-2] = NCCL;
            }
            do {
                if (c == FEOF)
                    goto cerror;
                if ((c == '-') && (cclcnt > 1) &&
                    (*sp != ']')) {
                    *ep = ep[-1];
                    ep++;
                    ep[-2] = MINUS;
                    cclcnt++;
                    continue;
                }
                *ep++ = c;
                cclcnt++;
            } while ((c = *sp++) != ']');
            lastep[1] = (char) cclcnt;
            continue;

        defchar:
        default:
            *ep++ = CCHR;
            *ep++ = c;
        }
    }
cerror:
    free(sep);
    return (0);
}

int
__size(char *strg)
{
    int i;

    i = 1;
    while (*strg++)
        i++;
    return (i);
}

intptr_t
__rpop(void)
{
    return ((*__sp_ == -1)?0:*__sp_--);
}

int
__rpush(char *ptr)
{
    if (__sp_ >= __stmax)
        return (0);
    *++__sp_ = (intptr_t)ptr;
    return (1);
}