freebsd-skq/bin/ed/re.c
1993-08-09 21:34:11 +00:00

150 lines
4.2 KiB
C

/* re.c: This file contains the regular expression interface routines for
the ed line editor. */
/*-
* Copyright (c) 1993 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley
* by Andrew Moore, Talke Studio.
*
* 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[] = "@(#)re.c 5.5 (Berkeley) 3/28/93";
#endif /* not lint */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "ed.h"
extern char *lhbuf;
extern int lhbufsz;
extern char *ibufp;
extern int ibufsz;
extern int patlock;
char errmsg[MAXFNAME + 40] = "";
/* optpat: return pointer to compiled pattern from command buffer */
pattern_t *
optpat()
{
static pattern_t *exp = NULL;
char *exps;
char delim;
int n;
if ((delim = *ibufp) == '\n') {
if (!exp) sprintf(errmsg, "no previous pattern");
return exp;
} else if (delim == ' ' || *++ibufp == '\n') {
sprintf(errmsg, "invalid pattern delimiter");
return NULL;
} else if (*ibufp == delim) {
if (!exp) sprintf(errmsg, "no previous pattern");
return exp;
} else if ((exps = getlhs(delim)) == NULL)
return NULL;
/* buffer alloc'd && not reserved */
if (exp && !patlock)
regfree(exp);
else if ((exp = (pattern_t *) malloc(sizeof(pattern_t))) == NULL) {
fprintf(stderr, "%s\n", strerror(errno));
sprintf(errmsg, "out of memory");
return NULL;
}
patlock = 0;
if (n = regcomp(exp, exps, 0)) {
regerror(n, exp, errmsg, sizeof errmsg);
return NULL;
}
return exp;
}
extern int isbinary;
/* getlhs: copy a pattern string from the command buffer; return pointer
to the copy */
char *
getlhs(delim)
int delim;
{
char *nd;
int len;
for (nd = ibufp; *nd != delim && *nd != '\n'; nd++)
switch (*nd) {
default:
break;
case '[':
if ((nd = ccl(++nd)) == NULL) {
sprintf(errmsg, "unbalanced brackets ([])");
return NULL;
}
break;
case '\\':
if (*++nd == '\n') {
sprintf(errmsg, "trailing backslash (\\)");
return NULL;
}
break;
}
len = nd - ibufp;
CKBUF(lhbuf, lhbufsz, len + 1, NULL);
memcpy(lhbuf, ibufp, len);
lhbuf[len] = '\0';
ibufp = nd;
return (isbinary) ? nultonl(lhbuf, len) : lhbuf;
}
/* ccl: expand a POSIX character class */
char *
ccl(s)
char *s;
{
int c, d;
if (*s == '^')
s++;
if (*s == ']')
s++;
for (; *s != ']' && *s != '\n'; s++)
if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '='))
for (s++, c = *++s; *s != ']' || c != d; s++)
if ((c = *s) == '\n')
return NULL;
return (*s == ']') ? s : NULL;
}