1 /* sub.c: This file contains the substitution routines for the ed
4 * Copyright (c) 1993 Andrew Moore, Talke Studio.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/cdefs.h>
33 static char *rhbuf; /* rhs substitution buffer */
34 static int rhbufsz; /* rhs substitution buffer size */
35 static int rhbufi; /* rhs substitution buffer index */
37 /* extract_subst_tail: extract substitution tail from the command buffer */
39 extract_subst_tail(int *flagp, long *np)
44 if ((delimiter = *ibufp) == '\n') {
48 } else if (extract_subst_template() == NULL)
50 else if (*ibufp == '\n') {
53 } else if (*ibufp == delimiter)
55 if ('1' <= *ibufp && *ibufp <= '9') {
58 } else if (*ibufp == 'g') {
67 /* extract_subst_template: return pointer to copy of substitution template
68 in the command buffer */
70 extract_subst_template(void)
75 char delimiter = *ibufp++;
77 if (*ibufp == '%' && *(ibufp + 1) == delimiter) {
80 errmsg = "no previous substitution";
83 while (*ibufp != delimiter) {
84 REALLOC(rhbuf, rhbufsz, i + 2, NULL);
85 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') {
90 else if ((rhbuf[i++] = *ibufp++) != '\n')
93 while ((n = get_tty_line()) == 0 ||
94 (n > 0 && ibuf[n - 1] != '\n'))
100 REALLOC(rhbuf, rhbufsz, i + 1, NULL);
101 rhbuf[rhbufi = i] = '\0';
106 static char *rbuf; /* substitute_matching_text buffer */
107 static int rbufsz; /* substitute_matching_text buffer size */
109 /* search_and_replace: for each line in a range, change text matching a pattern
110 according to a substitution template; return status */
112 search_and_replace(pattern_t *pat, int gflag, int kth)
118 long xa = current_addr;
123 current_addr = first_addr - 1;
124 for (lc = 0; lc <= second_addr - first_addr; lc++) {
125 lp = get_addressed_line_node(++current_addr);
126 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0)
130 if (delete_lines(current_addr, current_addr) < 0)
136 if ((txt = put_sbuf_line(txt)) == NULL) {
140 up->t = get_addressed_line_node(current_addr);
141 else if ((up = push_undo_stack(UADD,
142 current_addr, current_addr)) == NULL) {
146 } while (txt != eot);
153 if (nsubs == 0 && !(gflag & GLB)) {
156 } else if ((gflag & (GPR | GLS | GNP)) &&
157 display_lines(current_addr, current_addr, gflag) < 0)
163 /* substitute_matching_text: replace text matched by a pattern according to
164 a substitution template; return pointer to the modified text */
166 substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth)
172 regmatch_t rm[SE_MAX];
176 if ((txt = get_sbuf_line(lp)) == NULL)
179 NUL_TO_NEWLINE(txt, lp->len);
181 if (!regexec(pat, txt, SE_MAX, rm, 0)) {
183 if (!kth || kth == ++matchno) {
186 REALLOC(rbuf, rbufsz, off + i, ERR);
188 NEWLINE_TO_NUL(txt, rm[0].rm_eo);
189 memcpy(rbuf + off, txt, i);
191 if ((off = apply_subst_template(txt, rm, off,
196 REALLOC(rbuf, rbufsz, off + i, ERR);
198 NEWLINE_TO_NUL(txt, i);
199 memcpy(rbuf + off, txt, i);
204 (!changed || ((gflag & GSG) && rm[0].rm_eo)) &&
205 !regexec(pat, txt, SE_MAX, rm, REG_NOTBOL));
207 REALLOC(rbuf, rbufsz, off + i + 2, ERR);
208 if (i > 0 && !rm[0].rm_eo && (gflag & GSG)) {
209 errmsg = "infinite substitution loop";
213 NEWLINE_TO_NUL(txt, i);
214 memcpy(rbuf + off, txt, i);
215 memcpy(rbuf + off + i, "\n", 2);
217 return changed ? off + i + 1 : 0;
221 /* apply_subst_template: modify text according to a substitution template;
222 return offset to end of modified text */
224 apply_subst_template(const char *boln, regmatch_t *rm, int off, int re_nsub)
231 for (; sub - rhbuf < rhbufi; sub++)
235 REALLOC(rbuf, rbufsz, off + k - j, ERR);
237 rbuf[off++] = boln[j++];
238 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' &&
239 (n = *sub - '0') <= re_nsub) {
242 REALLOC(rbuf, rbufsz, off + k - j, ERR);
244 rbuf[off++] = boln[j++];
246 REALLOC(rbuf, rbufsz, off + 1, ERR);
249 REALLOC(rbuf, rbufsz, off + 1, ERR);