BSD 4_4 release

[unix-history] / usr / src / contrib / ed / get_pattern.c

/*-
* Copyright (c) 1992, 1993
*      The Regents of the University of California.  All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rodney Ruddock of the University of Guelph.
*
* 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. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Berkeley and its contributors.
* 4. 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.
*/

#ifndef lint
static char sccsid[] = "@(#)get_pattern.c       8.1 (Berkeley) 5/31/93";
#endif /* not lint */

#include <sys/types.h>

#include <regex.h>
#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef DBI
#include <db.h>
#endif

#include "ed.h"
#include "extern.h"

/*
* This is for getting RE and replacement patterns for any command
* that uses RE's and replacements.
*/
char *
get_pattern(delim, inputt, errnum, flag)
       int delim, *errnum, flag;
       FILE *inputt;
{
       static int l_max = 510;
       int l_cnt = 1;
       char *l_pat, *l_pat_tmp;

       /* get a "reasonable amount of space for the RE */
       l_pat = calloc(l_max + 2, sizeof(char));
       if (l_pat == NULL) {
               *errnum = -3;
               strcpy(help_msg, "out of memory error");
               return (NULL);
       }
       l_pat[0] = delim;

       if ((delim == ' ') || (delim == '\n')) {
               if (delim == '\n')
                       ungetc(delim, inputt);
               strcpy(help_msg, "illegal delimiter");
               *errnum = -2;
               return (l_pat);
       }
       for (;;) {
               ss = getc(inputt);
               if (ss == '\\') {
                       ss = getc(inputt);
                       if ((ss == delim) || ((flag == 1) && (ss == '\n')))
                               l_pat[l_cnt] = ss;
                       else {
                               l_pat[l_cnt] = '\\';
                               l_pat[++l_cnt] = ss;
                       }
                       goto leap;
               } else
                       if ((ss == '\n') || (ss == EOF)) {
                               ungetc(ss, inputt);
                               strcpy(help_msg, "no closing delimiter found");
                               *errnum = -1;
                               /* This is done for s's backward compat. */
                               l_pat[l_cnt] = '\0';
                               return (l_pat);
                       }
               if (ss == delim)
                       break;

               l_pat[l_cnt] = ss;

leap:           if (l_cnt > l_max) {
                       /* The RE is really long; get more space for it. */
                       l_max = l_max + 256;
                       l_pat_tmp = l_pat;
                       l_pat = calloc(l_max + 2, sizeof(char));
                       if (l_pat == NULL) {
                               *errnum = -3;
                               strcpy(help_msg, "out of memory error");
                               return (NULL);
                       }
                       memmove(l_pat, l_pat_tmp, l_cnt);
                       free(l_pat_tmp);
               }
               l_cnt++;
       }
       l_pat[l_cnt] = '\0';
       *errnum = 0;
       /*
        * Send back the pattern.  l_pat[0] has the delimiter in it so the RE
        * really starts at l_pat[1]. It's done this way for the special forms
        * of 's' (substitute).
        */
       return (l_pat);
}