sub.c
1 /* sub.c: This file contains the substitution routines for the ed
2 line editor */
3 /*-
4 * Copyright (c) 1993 Andrew Moore, Talke Studio.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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.
15 *
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
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD: src/bin/ed/sub.c,v 1.15 2002/06/30 05:13:53 obrien Exp $");
31
32 #include "ed.h"
33
34
35 char *rhbuf; /* rhs substitution buffer */
36 int rhbufsz; /* rhs substitution buffer size */
37 int rhbufi; /* rhs substitution buffer index */
38
39 /* extract_subst_tail: extract substitution tail from the command buffer */
40 int
41 extract_subst_tail(int *flagp, long *np)
42 {
43 char delimiter;
44
45 *flagp = *np = 0;
46 if ((delimiter = *ibufp) == '\n') {
47 rhbufi = 0;
48 *flagp = GPR;
49 return 0;
50 } else if (extract_subst_template() == NULL)
51 return ERR;
52 else if (*ibufp == '\n') {
53 *flagp = GPR;
54 return 0;
55 } else if (*ibufp == delimiter)
56 ibufp++;
57 if ('1' <= *ibufp && *ibufp <= '9') {
58 STRTOL(*np, ibufp);
59 return 0;
60 } else if (*ibufp == 'g') {
61 ibufp++;
62 *flagp = GSG;
63 return 0;
64 }
65 return 0;
66 }
67
68
69 /* extract_subst_template: return pointer to copy of substitution template
70 in the command buffer */
71 char *
72 extract_subst_template(void)
73 {
74 int n = 0;
75 int i = 0;
76 char c;
77 char delimiter = *ibufp++;
78
79 if (*ibufp == '%' && *(ibufp + 1) == delimiter) {
80 ibufp++;
81 if (!rhbuf)
82 errmsg = "no previous substitution";
83 return rhbuf;
84 }
85 while (*ibufp != delimiter) {
86 REALLOC(rhbuf, rhbufsz, i + 2, NULL);
87 if ((c = rhbuf[i++] = *ibufp++) == '\n' && *ibufp == '\0') {
88 i--, ibufp--;
89 break;
90 } else if (c != '\\')
91 ;
92 else if ((rhbuf[i++] = *ibufp++) != '\n')
93 ;
94 else if (!isglobal) {
95 while ((n = get_tty_line()) == 0 ||
96 (n > 0 && ibuf[n - 1] != '\n'))
97 clearerr(stdin);
98 if (n < 0)
99 return NULL;
100 }
101 }
102 REALLOC(rhbuf, rhbufsz, i + 1, NULL);
103 rhbuf[rhbufi = i] = '\0';
104 return rhbuf;
105 }
106
107
108 char *rbuf; /* substitute_matching_text buffer */
109 int rbufsz; /* substitute_matching_text buffer size */
110
111 /* search_and_replace: for each line in a range, change text matching a pattern
112 according to a substitution template; return status */
113 int
114 search_and_replace(pattern_t *pat, int gflag, int kth)
115 {
116 undo_t *up;
117 const char *txt;
118 const char *eot;
119 long lc;
120 long xa = current_addr;
121 int nsubs = 0;
122 line_t *lp;
123 int len;
124
125 current_addr = first_addr - 1;
126 for (lc = 0; lc <= second_addr - first_addr; lc++) {
127 lp = get_addressed_line_node(++current_addr);
128 if ((len = substitute_matching_text(pat, lp, gflag, kth)) < 0)
129 return ERR;
130 else if (len) {
131 up = NULL;
132 if (delete_lines(current_addr, current_addr) < 0)
133 return ERR;
134 txt = rbuf;
135 eot = rbuf + len;
136 SPL1();
137 do {
138 if ((txt = put_sbuf_line(txt)) == NULL) {
139 SPL0();
140 return ERR;
141 } else if (up)
142 up->t = get_addressed_line_node(current_addr);
143 else if ((up = push_undo_stack(UADD,
144 current_addr, current_addr)) == NULL) {
145 SPL0();
146 return ERR;
147 }
148 } while (txt != eot);
149 SPL0();
150 nsubs++;
151 /* 3751351 */
152 replace_marks(lp, get_addressed_line_node(current_addr));
153 xa = current_addr;
154 }
155 }
156 current_addr = xa;
157 if (nsubs == 0 && !(gflag & GLB)) {
158 errmsg = "no match";
159 return ERR;
160 } else if ((gflag & (GPR | GLS | GNP)) &&
161 display_lines(current_addr, current_addr, gflag) < 0)
162 return ERR;
163 return 0;
164 }
165
166
167 /* substitute_matching_text: replace text matched by a pattern according to
168 a substitution template; return pointer to the modified text */
169 int
170 substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth)
171 {
172 int off = 0;
173 int changed = 0;
174 int matchno = 0;
175 int i = 0;
176 regmatch_t rm[SE_MAX];
177 char *txt;
178 char *eot;
179
180 if ((txt = get_sbuf_line(lp)) == NULL)
181 return ERR;
182 if (isbinary)
183 NUL_TO_NEWLINE(txt, lp->len);
184 eot = txt + lp->len;
185 if (!regexec(pat, txt, SE_MAX, rm, 0)) {
186 do {
187 if (!kth || kth == ++matchno) {
188 changed++;
189 i = rm[0].rm_so;
190 REALLOC(rbuf, rbufsz, off + i, ERR);
191 if (isbinary)
192 NEWLINE_TO_NUL(txt, rm[0].rm_eo);
193 memcpy(rbuf + off, txt, i);
194 off += i;
195 if ((off = apply_subst_template(txt, rm, off,
196 pat->re_nsub)) < 0)
197 return ERR;
198 } else {
199 i = rm[0].rm_eo;
200 REALLOC(rbuf, rbufsz, off + i, ERR);
201 if (isbinary)
202 NEWLINE_TO_NUL(txt, i);
203 memcpy(rbuf + off, txt, i);
204 off += i;
205 }
206 txt += rm[0].rm_eo;
207 } while (*txt &&
208 (!changed || ((gflag & GSG) && rm[0].rm_eo)) &&
209 !regexec(pat, txt, SE_MAX, rm, REG_NOTBOL));
210 i = eot - txt;
211 REALLOC(rbuf, rbufsz, off + i + 2, ERR);
212 if (i > 0 && !rm[0].rm_eo && (gflag & GSG)) {
213 errmsg = "infinite substitution loop";
214 return ERR;
215 }
216 if (isbinary)
217 NEWLINE_TO_NUL(txt, i);
218 memcpy(rbuf + off, txt, i);
219 memcpy(rbuf + off + i, "\n", 2);
220 }
221 return changed ? off + i + 1 : 0;
222 }
223
224
225 /* apply_subst_template: modify text according to a substitution template;
226 return offset to end of modified text */
227 int
228 apply_subst_template(const char *boln, regmatch_t *rm, int off, int re_nsub)
229 {
230 int j = 0;
231 int k = 0;
232 int n;
233 char *sub = rhbuf;
234
235 for (; sub - rhbuf < rhbufi; sub++)
236 if (*sub == '&') {
237 j = rm[0].rm_so;
238 k = rm[0].rm_eo;
239 REALLOC(rbuf, rbufsz, off + k - j, ERR);
240 while (j < k)
241 rbuf[off++] = boln[j++];
242 } else if (*sub == '\\' && '1' <= *++sub && *sub <= '9' &&
243 (n = *sub - '0') <= re_nsub) {
244 j = rm[n].rm_so;
245 k = rm[n].rm_eo;
246 REALLOC(rbuf, rbufsz, off + k - j, ERR);
247 while (j < k)
248 rbuf[off++] = boln[j++];
249 } else {
250 REALLOC(rbuf, rbufsz, off + 1, ERR);
251 rbuf[off++] = *sub;
252 }
253 REALLOC(rbuf, rbufsz, off + 1, ERR);
254 rbuf[off] = '\0';
255 return off;
256 }
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