xref: /freebsd/contrib/nvi/vi/v_replace.c (revision ea906c4152774dff300bb26fbfc1e4188351c89a)
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[] = "@(#)v_replace.c	10.17 (Berkeley) 6/30/96";
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(sp, vp)
47 	SCR *sp;
48 	VICMD *vp;
49 {
50 	EVENT ev;
51 	VI_PRIVATE *vip;
52 	TEXT *tp;
53 	size_t blen, len;
54 	u_long cnt;
55 	int quote, rval;
56 	char *bp, *p;
57 
58 	vip = VIP(sp);
59 
60 	/*
61 	 * If the line doesn't exist, or it's empty, replacement isn't
62 	 * allowed.  It's not hard to implement, but:
63 	 *
64 	 *	1: It's historic practice (vi beeped before the replacement
65 	 *	   character was even entered).
66 	 *	2: For consistency, this change would require that the more
67 	 *	   general case, "Nr", when the user is < N characters from
68 	 *	   the end of the line, also work, which would be a bit odd.
69 	 *	3: Replacing with a <newline> has somewhat odd semantics.
70 	 */
71 	if (db_get(sp, vp->m_start.lno, DBG_FATAL, &p, &len))
72 		return (1);
73 	if (len == 0) {
74 		msgq(sp, M_BERR, "186|No characters to replace");
75 		return (1);
76 	}
77 
78 	/*
79 	 * Figure out how many characters to be replace.  For no particular
80 	 * reason (other than that the semantics of replacing the newline
81 	 * are confusing) only permit the replacement of the characters in
82 	 * the current line.  I suppose we could append replacement characters
83 	 * to the line, but I see no compelling reason to do so.  Check this
84 	 * before we get the character to match historic practice, where Nr
85 	 * failed immediately if there were less than N characters from the
86 	 * cursor to the end of the line.
87 	 */
88 	cnt = F_ISSET(vp, VC_C1SET) ? vp->count : 1;
89 	vp->m_stop.lno = vp->m_start.lno;
90 	vp->m_stop.cno = vp->m_start.cno + cnt - 1;
91 	if (vp->m_stop.cno > len - 1) {
92 		v_eol(sp, &vp->m_start);
93 		return (1);
94 	}
95 
96 	/*
97 	 * If it's not a repeat, reset the current mode and get a replacement
98 	 * character.
99 	 */
100 	quote = 0;
101 	if (!F_ISSET(vp, VC_ISDOT)) {
102 		sp->showmode = SM_REPLACE;
103 		if (vs_refresh(sp, 0))
104 			return (1);
105 next:		if (v_event_get(sp, &ev, 0, 0))
106 			return (1);
107 
108 		switch (ev.e_event) {
109 		case E_CHARACTER:
110 			/*
111 			 * <literal_next> means escape the next character.
112 			 * <escape> means they changed their minds.
113 			 */
114 			if (!quote) {
115 				if (ev.e_value == K_VLNEXT) {
116 					quote = 1;
117 					goto next;
118 				}
119 				if (ev.e_value == K_ESCAPE)
120 					return (0);
121 			}
122 			vip->rlast = ev.e_c;
123 			vip->rvalue = ev.e_value;
124 			break;
125 		case E_ERR:
126 		case E_EOF:
127 			F_SET(sp, SC_EXIT_FORCE);
128 			return (1);
129 		case E_INTERRUPT:
130 			/* <interrupt> means they changed their minds. */
131 			return (0);
132 		case E_WRESIZE:
133 			/* <resize> interrupts the input mode. */
134 			v_emsg(sp, NULL, VIM_WRESIZE);
135 			return (0);
136 		case E_REPAINT:
137 			if (vs_repaint(sp, &ev))
138 				return (1);
139 			goto next;
140 		default:
141 			v_event_err(sp, &ev);
142 			return (0);
143 		}
144 	}
145 
146 	/* Copy the line. */
147 	GET_SPACE_RET(sp, bp, blen, len);
148 	memmove(bp, p, len);
149 	p = bp;
150 
151 	/*
152 	 * Versions of nvi before 1.57 created N new lines when they replaced
153 	 * N characters with <carriage-return> or <newline> characters.  This
154 	 * is different from the historic vi, which replaced N characters with
155 	 * a single new line.  Users complained, so we match historic practice.
156 	 */
157 	if (!quote && vip->rvalue == K_CR || vip->rvalue == K_NL) {
158 		/* Set return line. */
159 		vp->m_stop.lno = vp->m_start.lno + 1;
160 		vp->m_stop.cno = 0;
161 
162 		/* The first part of the current line. */
163 		if (db_set(sp, vp->m_start.lno, p, vp->m_start.cno))
164 			goto err_ret;
165 
166 		/*
167 		 * The rest of the current line.  And, of course, now it gets
168 		 * tricky.  If there are characters left in the line and if
169 		 * the autoindent edit option is set, white space after the
170 		 * replaced character is discarded, autoindent is applied, and
171 		 * the cursor moves to the last indent character.
172 		 */
173 		p += vp->m_start.cno + cnt;
174 		len -= vp->m_start.cno + cnt;
175 		if (len != 0 && O_ISSET(sp, O_AUTOINDENT))
176 			for (; len && isblank(*p); --len, ++p);
177 
178 		if ((tp = text_init(sp, p, len, len)) == NULL)
179 			goto err_ret;
180 
181 		if (len != 0 && O_ISSET(sp, O_AUTOINDENT)) {
182 			if (v_txt_auto(sp, vp->m_start.lno, NULL, 0, tp))
183 				goto err_ret;
184 			vp->m_stop.cno = tp->ai ? tp->ai - 1 : 0;
185 		} else
186 			vp->m_stop.cno = 0;
187 
188 		vp->m_stop.cno = tp->ai ? tp->ai - 1 : 0;
189 		if (db_append(sp, 1, vp->m_start.lno, tp->lb, tp->len))
190 err_ret:		rval = 1;
191 		else {
192 			text_free(tp);
193 			rval = 0;
194 		}
195 	} else {
196 		memset(bp + vp->m_start.cno, vip->rlast, cnt);
197 		rval = db_set(sp, vp->m_start.lno, bp, len);
198 	}
199 	FREE_SPACE(sp, bp, blen);
200 
201 	vp->m_final = vp->m_stop;
202 	return (rval);
203 }
204