1/*	$NetBSD: sub.c,v 1.6 2005/02/17 16:29:26 xtraeme Exp $	*/
2
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.
8 *
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.
17 *
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.
29 */
30
31#include <sys/cdefs.h>
32#ifndef lint
33#if 0
34static char *rcsid = "@(#)sub.c,v 1.1 1994/02/01 00:34:44 alm Exp";
35#else
36__RCSID("$NetBSD: sub.c,v 1.6 2005/02/17 16:29:26 xtraeme Exp $");
37#endif
38#endif /* not lint */
39
40#include "ed.h"
41
42
43char *rhbuf;			/* rhs substitution buffer */
44int rhbufsz;			/* rhs substitution buffer size */
45int rhbufi;			/* rhs substitution buffer index */
46
47/* extract_subst_tail: extract substitution tail from the command buffer */
48int
49extract_subst_tail(int *flagp, long *np)
50{
51	char delimiter;
52
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;
72	}
73	return 0;
74}
75
76
77/* extract_subst_template: return pointer to copy of substitution template
78   in the command buffer */
79char *
80extract_subst_template(void)
81{
82	int n = 0;
83	int i = 0;
84	char c;
85	char delimiter = *ibufp++;
86
87	if (*ibufp == '%' && *(ibufp + 1) == delimiter) {
88		ibufp++;
89		if (!rhbuf) sprintf(errmsg, "no previous substitution");
90		return rhbuf;
91	}
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 != '\\')
98			;
99		else if ((rhbuf[i++] = *ibufp++) != '\n')
100			;
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;
107		}
108	}
109	REALLOC(rhbuf, rhbufsz, i + 1, NULL);
110	rhbuf[rhbufi = i] = '\0';
111	return  rhbuf;
112}
113
114
115char *rbuf;			/* substitute_matching_text buffer */
116int rbufsz;			/* substitute_matching_text buffer size */
117
118/* search_and_replace: for each line in a range, change text matching a pattern
119   according to a substitution template; return status  */
120int
121search_and_replace(pattern_t *pat, int gflag, int kth)
122{
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;
131
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;
154				}
155			} while (txt != eot);
156			SPL0();
157			nsubs++;
158			xa = current_addr;
159		}
160	}
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;
169}
170
171
172/* substitute_matching_text: replace text matched by a pattern according to
173   a substitution template; return pointer to the modified text */
174int
175substitute_matching_text(pattern_t *pat, line_t *lp, int gflag, int kth)
176{
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;
184
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;
210			}
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;
219		}
220		if (isbinary)
221			NEWLINE_TO_NUL(txt, i);
222		memcpy(rbuf + off, txt, i);
223		memcpy(rbuf + off + i, "\n", 2);
224	}
225	return changed ? off + i + 1 : 0;
226}
227
228
229/* apply_subst_template: modify text according to a substitution template;
230   return offset to end of modified text */
231int
232apply_subst_template(char *boln, regmatch_t *rm, int off, int re_nsub)
233{
234	int j = 0;
235	int k = 0;
236	int n;
237	char *sub = rhbuf;
238
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;
256		}
257	REALLOC(rbuf, rbufsz, off + 1, ERR);
258	rbuf[off] = '\0';
259	return off;
260}
261