xref: /freebsd/contrib/nvi/vi/v_match.c (revision d5566384042fa631ffe7916fd89bcb4669ad12a7)
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_match.c	10.8 (Berkeley) 3/6/96";
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 <limits.h>
22 #include <stdio.h>
23 #include <string.h>
24 
25 #include "../common/common.h"
26 #include "vi.h"
27 
28 /*
29  * v_match -- %
30  *	Search to matching character.
31  *
32  * PUBLIC: int v_match __P((SCR *, VICMD *));
33  */
34 int
35 v_match(sp, vp)
36 	SCR *sp;
37 	VICMD *vp;
38 {
39 	VCS cs;
40 	MARK *mp;
41 	size_t cno, len, off;
42 	int cnt, isempty, matchc, startc, (*gc)__P((SCR *, VCS *));
43 	char *p;
44 
45 	/*
46 	 * !!!
47 	 * Historic practice; ignore the count.
48 	 *
49 	 * !!!
50 	 * Historical practice was to search for the initial character in the
51 	 * forward direction only.
52 	 */
53 	if (db_eget(sp, vp->m_start.lno, &p, &len, &isempty)) {
54 		if (isempty)
55 			goto nomatch;
56 		return (1);
57 	}
58 	for (off = vp->m_start.cno;; ++off) {
59 		if (off >= len) {
60 nomatch:		msgq(sp, M_BERR, "184|No match character on this line");
61 			return (1);
62 		}
63 		switch (startc = p[off]) {
64 		case '(':
65 			matchc = ')';
66 			gc = cs_next;
67 			break;
68 		case ')':
69 			matchc = '(';
70 			gc = cs_prev;
71 			break;
72 		case '[':
73 			matchc = ']';
74 			gc = cs_next;
75 			break;
76 		case ']':
77 			matchc = '[';
78 			gc = cs_prev;
79 			break;
80 		case '{':
81 			matchc = '}';
82 			gc = cs_next;
83 			break;
84 		case '}':
85 			matchc = '{';
86 			gc = cs_prev;
87 			break;
88 		case '<':
89 			matchc = '>';
90 			gc = cs_next;
91 			break;
92 		case '>':
93 			matchc = '<';
94 			gc = cs_prev;
95 			break;
96 		default:
97 			continue;
98 		}
99 		break;
100 	}
101 
102 	cs.cs_lno = vp->m_start.lno;
103 	cs.cs_cno = off;
104 	if (cs_init(sp, &cs))
105 		return (1);
106 	for (cnt = 1;;) {
107 		if (gc(sp, &cs))
108 			return (1);
109 		if (cs.cs_flags != 0) {
110 			if (cs.cs_flags == CS_EOF || cs.cs_flags == CS_SOF)
111 				break;
112 			continue;
113 		}
114 		if (cs.cs_ch == startc)
115 			++cnt;
116 		else if (cs.cs_ch == matchc && --cnt == 0)
117 			break;
118 	}
119 	if (cnt) {
120 		msgq(sp, M_BERR, "185|Matching character not found");
121 		return (1);
122 	}
123 
124 	vp->m_stop.lno = cs.cs_lno;
125 	vp->m_stop.cno = cs.cs_cno;
126 
127 	/*
128 	 * If moving right, non-motion commands move to the end of the range.
129 	 * Delete and yank stay at the start.
130 	 *
131 	 * If moving left, all commands move to the end of the range.
132 	 *
133 	 * !!!
134 	 * Don't correct for leftward movement -- historic vi deleted the
135 	 * starting cursor position when deleting to a match.
136 	 */
137 	if (vp->m_start.lno < vp->m_stop.lno ||
138 	    vp->m_start.lno == vp->m_stop.lno &&
139 	    vp->m_start.cno < vp->m_stop.cno)
140 		vp->m_final = ISMOTION(vp) ? vp->m_start : vp->m_stop;
141 	else
142 		vp->m_final = vp->m_stop;
143 
144 	/*
145 	 * !!!
146 	 * If the motion is across lines, and the earliest cursor position
147 	 * is at or before any non-blank characters in the line, i.e. the
148 	 * movement is cutting all of the line's text, and the later cursor
149 	 * position has nothing other than whitespace characters between it
150 	 * and the end of its line, the buffer is in line mode.
151 	 */
152 	if (!ISMOTION(vp) || vp->m_start.lno == vp->m_stop.lno)
153 		return (0);
154 	mp = vp->m_start.lno < vp->m_stop.lno ? &vp->m_start : &vp->m_stop;
155 	if (mp->cno != 0) {
156 		cno = 0;
157 		if (nonblank(sp, mp->lno, &cno))
158 			return (1);
159 		if (cno < mp->cno)
160 			return (0);
161 	}
162 	mp = vp->m_start.lno < vp->m_stop.lno ? &vp->m_stop : &vp->m_start;
163 	if (db_get(sp, mp->lno, DBG_FATAL, &p, &len))
164 		return (1);
165 	for (p += mp->cno + 1, len -= mp->cno; --len; ++p)
166 		if (!isblank(*p))
167 			return (0);
168 	F_SET(vp, VM_LMODE);
169 	return (0);
170 }
171