xref: /freebsd/contrib/nvi/vi/v_replace.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
1 /*-
2  * Copyright (c) 1992, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
5  *	Keith Bostic.  All rights reserved.
6  *
7  * See the LICENSE file for redistribution information.
8  */
9 
10 #include "config.h"
11 
12 #ifndef lint
13 static const char sccsid[] = "$Id: v_replace.c,v 10.24 2001/06/25 15:19:34 skimo Exp $";
14 #endif /* not lint */
15 
16 #include <sys/types.h>
17 #include <sys/queue.h>
18 #include <sys/time.h>
19 
20 #include <bitstring.h>
21 #include <ctype.h>
22 #include <errno.h>
23 #include <limits.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 
28 #include "../common/common.h"
29 #include "vi.h"
30 
31 /*
32  * v_replace -- [count]r<char>
33  *
34  * !!!
35  * The r command in historic vi was almost beautiful in its badness.  For
36  * example, "r<erase>" and "r<word erase>" beeped the terminal and deleted
37  * a single character.  "Nr<carriage return>", where N was greater than 1,
38  * inserted a single carriage return.  "r<escape>" did cancel the command,
39  * but "r<literal><escape>" erased a single character.  To enter a literal
40  * <literal> character, it required three <literal> characters after the
41  * command.  This may not be right, but at least it's not insane.
42  *
43  * PUBLIC: int v_replace __P((SCR *, VICMD *));
44  */
45 int
46 v_replace(SCR *sp, VICMD *vp)
47 {
48 	EVENT ev;
49 	VI_PRIVATE *vip;
50 	TEXT *tp;
51 	size_t blen, len;
52 	u_long cnt;
53 	int quote, rval;
54 	CHAR_T *bp;
55 	CHAR_T *p;
56 
57 	vip = VIP(sp);
58 
59 	/*
60 	 * If the line doesn't exist, or it's empty, replacement isn't
61 	 * allowed.  It's not hard to implement, but:
62 	 *
63 	 *	1: It's historic practice (vi beeped before the replacement
64 	 *	   character was even entered).
65 	 *	2: For consistency, this change would require that the more
66 	 *	   general case, "Nr", when the user is < N characters from
67 	 *	   the end of the line, also work, which would be a bit odd.
68 	 *	3: Replacing with a <newline> has somewhat odd semantics.
69 	 */
70 	if (db_get(sp, vp->m_start.lno, DBG_FATAL, &p, &len))
71 		return (1);
72 	if (len == 0) {
73 		msgq(sp, M_BERR, "186|No characters to replace");
74 		return (1);
75 	}
76 
77 	/*
78 	 * Figure out how many characters to be replace.  For no particular
79 	 * reason (other than that the semantics of replacing the newline
80 	 * are confusing) only permit the replacement of the characters in
81 	 * the current line.  I suppose we could append replacement characters
82 	 * to the line, but I see no compelling reason to do so.  Check this
83 	 * before we get the character to match historic practice, where Nr
84 	 * failed immediately if there were less than N characters from the
85 	 * cursor to the end of the line.
86 	 */
87 	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
88 	vp->m_stop.lno = vp->m_start.lno;
89 	vp->m_stop.cno = vp->m_start.cno + cnt - 1;
90 	if (vp->m_stop.cno > len - 1) {
91 		v_eol(sp, &vp->m_start);
92 		return (1);
93 	}
94 
95 	/*
96 	 * If it's not a repeat, reset the current mode and get a replacement
97 	 * character.
98 	 */
99 	quote = 0;
100 	if (!F_ISSET(vp, VC_ISDOT)) {
101 		sp->showmode = SM_REPLACE;
102 		if (vs_refresh(sp, 0))
103 			return (1);
104 next:		if (v_event_get(sp, &ev, 0, 0))
105 			return (1);
106 
107 		switch (ev.e_event) {
108 		case E_CHARACTER:
109 			/*
110 			 * <literal_next> means escape the next character.
111 			 * <escape> means they changed their minds.
112 			 */
113 			if (!quote) {
114 				if (ev.e_value == K_VLNEXT) {
115 					quote = 1;
116 					goto next;
117 				}
118 				if (ev.e_value == K_ESCAPE)
119 					return (0);
120 			}
121 			vip->rlast = ev.e_c;
122 			vip->rvalue = ev.e_value;
123 			break;
124 		case E_ERR:
125 		case E_EOF:
126 			F_SET(sp, SC_EXIT_FORCE);
127 			return (1);
128 		case E_INTERRUPT:
129 			/* <interrupt> means they changed their minds. */
130 			return (0);
131 		case E_WRESIZE:
132 			/* <resize> interrupts the input mode. */
133 			v_emsg(sp, NULL, VIM_WRESIZE);
134 			return (0);
135 		case E_REPAINT:
136 			if (vs_repaint(sp, &ev))
137 				return (1);
138 			goto next;
139 		default:
140 			v_event_err(sp, &ev);
141 			return (0);
142 		}
143 	}
144 
145 	/* Copy the line. */
146 	GET_SPACE_RETW(sp, bp, blen, len);
147 	MEMMOVE(bp, p, len);
148 	p = bp;
149 
150 	/*
151 	 * Versions of nvi before 1.57 created N new lines when they replaced
152 	 * N characters with <carriage-return> or <newline> characters.  This
153 	 * is different from the historic vi, which replaced N characters with
154 	 * a single new line.  Users complained, so we match historic practice.
155 	 */
156 	if ((!quote && vip->rvalue == K_CR) || vip->rvalue == K_NL) {
157 		/* Set return line. */
158 		vp->m_stop.lno = vp->m_start.lno + 1;
159 		vp->m_stop.cno = 0;
160 
161 		/* The first part of the current line. */
162 		if (db_set(sp, vp->m_start.lno, p, vp->m_start.cno))
163 			goto err_ret;
164 
165 		/*
166 		 * The rest of the current line.  And, of course, now it gets
167 		 * tricky.  If there are characters left in the line and if
168 		 * the autoindent edit option is set, white space after the
169 		 * replaced character is discarded, autoindent is applied, and
170 		 * the cursor moves to the last indent character.
171 		 */
172 		p += vp->m_start.cno + cnt;
173 		len -= vp->m_start.cno + cnt;
174 		if (len != 0 && O_ISSET(sp, O_AUTOINDENT))
175 			for (; len && isblank(*p); --len, ++p);
176 
177 		if ((tp = text_init(sp, p, len, len)) == NULL)
178 			goto err_ret;
179 
180 		if (len != 0 && O_ISSET(sp, O_AUTOINDENT)) {
181 			if (v_txt_auto(sp, vp->m_start.lno, NULL, 0, tp))
182 				goto err_ret;
183 			vp->m_stop.cno = tp->ai ? tp->ai - 1 : 0;
184 		} else
185 			vp->m_stop.cno = 0;
186 
187 		vp->m_stop.cno = tp->ai ? tp->ai - 1 : 0;
188 		if (db_append(sp, 1, vp->m_start.lno, tp->lb, tp->len))
189 err_ret:		rval = 1;
190 		else {
191 			text_free(tp);
192 			rval = 0;
193 		}
194 	} else {
195 		STRSET(bp + vp->m_start.cno, vip->rlast, cnt);
196 		rval = db_set(sp, vp->m_start.lno, bp, len);
197 	}
198 	FREE_SPACEW(sp, bp, blen);
199 
200 	vp->m_final = vp->m_stop;
201 	return (rval);
202 }
203