Do not try to mmap a zero length file.
[netbsd-mini2440.git] / bin / ed / sub.c
blobb29d8ddd079c1783662cef95b15977a8c751cbb5
1 /* $NetBSD: sub.c,v 1.5 1997/07/20 06:35:41 thorpej Exp $ */
3 /* sub.c: This file contains the substitution routines for the ed
4 line editor */
5 /*-
6 * Copyright (c) 1993 Andrew Moore, Talke Studio.
7 * All rights reserved.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
31 #include <sys/cdefs.h>
32 #ifndef lint
33 #if 0
34 static char *rcsid = "@(#)sub.c,v 1.1 1994/02/01 00:34:44 alm Exp";
35 #else
36 __RCSID("$NetBSD: sub.c,v 1.5 1997/07/20 06:35:41 thorpej Exp $");
37 #endif
38 #endif /* not lint */
40 #include "ed.h"
43 char *rhbuf; /* rhs substitution buffer */
44 int rhbufsz; /* rhs substitution buffer size */
45 int rhbufi; /* rhs substitution buffer index */
47 /* extract_subst_tail: extract substitution tail from the command buffer */
48 int
49 extract_subst_tail(int *flagp, long *np)
51 char delimiter;
53 *flagp = *np = 0;
54 if ((delimiter = *ibufp) == '\n') {
55 rhbufi = 0;
56 *flagp = GPR;
57 return 0;
58 } else if (extract_subst_template() == NULL)
59 return ERR;
60 else if (*ibufp == '\n') {
61 *flagp = GPR;
62 return 0;
63 } else if (*ibufp == delimiter)
64 ibufp++;
65 if ('1' <= *ibufp && *ibufp <= '9') {
66 STRTOL(*np, ibufp);
67 return 0;
68 } else if (*ibufp == 'g') {
69 ibufp++;
70 *flagp = GSG;
71 return 0;
73 return 0;
77 /* extract_subst_template: return pointer to copy of substitution template
78 in the command buffer */
79 char *
80 extract_subst_template(void)
82 int n = 0;
83 int i = 0;
84 char c;
85 char delimiter = *ibufp++;
87 if (*ibufp == '%' && *(ibufp + 1) == delimiter) {
88 ibufp++;
89 if (!rhbuf) sprintf(errmsg, "no previous substitution");
90 return rhbuf;
92 while (*ibufp != delimiter) {
93 REALLOC(rhbuf, rhbufsz, i + 2, NULL);
94 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') {
95 i--, ibufp--;
96 break;
97 } else if (c != '\\')
99 else if ((rhbuf[i++] = *ibufp++) != '\n')
101 else if (!isglobal) {
102 while ((n = get_tty_line()) == 0 ||
103 (n > 0 && ibuf[n - 1] != '\n'))
104 clearerr(stdin);
105 if (n < 0)
106 return NULL;
109 REALLOC(rhbuf, rhbufsz, i + 1, NULL);
110 rhbuf[rhbufi = i] = '\0';
111 return rhbuf;
115 char *rbuf; /* substitute_matching_text buffer */
116 int rbufsz; /* substitute_matching_text buffer size */
118 /* search_and_replace: for each line in a range, change text matching a pattern
119 according to a substitution template; return status */
121 search_and_replace(pattern_t *pat, int gflag, int kth)
123 undo_t *up;
124 char *txt;
125 char *eot;
126 long lc;
127 long xa = current_addr;
128 int nsubs = 0;
129 line_t *lp;
130 int len;
132 current_addr = first_addr - 1;
133 for (lc = 0; lc <= second_addr - first_addr; lc++) {
134 lp = get_addressed_line_node(++current_addr);
135 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0)
136 return ERR;
137 else if (len) {
138 up = NULL;
139 if (delete_lines(current_addr, current_addr) < 0)
140 return ERR;
141 txt = rbuf;
142 eot = rbuf + len;
143 SPL1();
144 do {
145 if ((txt = put_sbuf_line(txt)) == NULL) {
146 SPL0();
147 return ERR;
148 } else if (up)
149 up->t = get_addressed_line_node(current_addr);
150 else if ((up = push_undo_stack(UADD,
151 current_addr, current_addr)) == NULL) {
152 SPL0();
153 return ERR;
155 } while (txt != eot);
156 SPL0();
157 nsubs++;
158 xa = current_addr;
161 current_addr = xa;
162 if (nsubs == 0 && !(gflag & GLB)) {
163 sprintf(errmsg, "no match");
164 return ERR;
165 } else if ((gflag & (GPR | GLS | GNP)) &&
166 display_lines(current_addr, current_addr, gflag) < 0)
167 return ERR;
168 return 0;
172 /* substitute_matching_text: replace text matched by a pattern according to
173 a substitution template; return pointer to the modified text */
175 substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth)
177 int off = 0;
178 int changed = 0;
179 int matchno = 0;
180 int i = 0;
181 regmatch_t rm[SE_MAX];
182 char *txt;
183 char *eot;
185 if ((txt = get_sbuf_line(lp)) == NULL)
186 return ERR;
187 if (isbinary)
188 NUL_TO_NEWLINE(txt, lp->len);
189 eot = txt + lp->len;
190 if (!regexec(pat, txt, SE_MAX, rm, 0)) {
191 do {
192 if (!kth || kth == ++matchno) {
193 changed++;
194 i = rm[0].rm_so;
195 REALLOC(rbuf, rbufsz, off + i, ERR);
196 if (isbinary)
197 NEWLINE_TO_NUL(txt, rm[0].rm_eo);
198 memcpy(rbuf + off, txt, i);
199 off += i;
200 if ((off = apply_subst_template(txt, rm, off,
201 pat->re_nsub)) < 0)
202 return ERR;
203 } else {
204 i = rm[0].rm_eo;
205 REALLOC(rbuf, rbufsz, off + i, ERR);
206 if (isbinary)
207 NEWLINE_TO_NUL(txt, i);
208 memcpy(rbuf + off, txt, i);
209 off += i;
211 txt += rm[0].rm_eo;
212 } while (*txt && (!changed || ((gflag & GSG) && rm[0].rm_eo))
213 && !regexec(pat, txt, SE_MAX, rm, REG_NOTBOL));
214 i = eot - txt;
215 REALLOC(rbuf, rbufsz, off + i + 2, ERR);
216 if (i > 0 && !rm[0].rm_eo && (gflag & GSG)) {
217 sprintf(errmsg, "infinite substitution loop");
218 return ERR;
220 if (isbinary)
221 NEWLINE_TO_NUL(txt, i);
222 memcpy(rbuf + off, txt, i);
223 memcpy(rbuf + off + i, "\n", 2);
225 return changed ? off + i + 1 : 0;
229 /* apply_subst_template: modify text according to a substitution template;
230 return offset to end of modified text */
232 apply_subst_template(char *boln, regmatch_t *rm, int off, int re_nsub)
234 int j = 0;
235 int k = 0;
236 int n;
237 char *sub = rhbuf;
239 for (; sub - rhbuf < rhbufi; sub++)
240 if (*sub == '&') {
241 j = rm[0].rm_so;
242 k = rm[0].rm_eo;
243 REALLOC(rbuf, rbufsz, off + k - j, ERR);
244 while (j < k)
245 rbuf[off++] = boln[j++];
246 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' &&
247 (n = *sub - '0') <= re_nsub) {
248 j = rm[n].rm_so;
249 k = rm[n].rm_eo;
250 REALLOC(rbuf, rbufsz, off + k - j, ERR);
251 while (j < k)
252 rbuf[off++] = boln[j++];
253 } else {
254 REALLOC(rbuf, rbufsz, off + 1, ERR);
255 rbuf[off++] = *sub;
257 REALLOC(rbuf, rbufsz, off + 1, ERR);
258 rbuf[off] = '\0';
259 return off;