1 /* parens.c -- implementation of matching parentheses feature. */
2
3 /* Copyright (C) 1987, 1989, 1992-2009 Free Software Foundation, Inc.
4
5 This file is part of the GNU Readline Library (Readline), a library
6 for reading lines of text with interactive input and history editing.
7
8 Readline is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
12
13 Readline is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with Readline. If not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #define READLINE_LIBRARY
23
24 #if defined (__TANDEM)
25 # include <floss.h>
26 #endif
27
28 #include "rlconf.h"
29
30 #if defined (HAVE_CONFIG_H)
31 # include <config.h>
32 #endif
33
34 #include <stdio.h>
35 #include <sys/types.h>
36
37 #if defined (HAVE_UNISTD_H)
38 # include <unistd.h>
39 #endif
40
41 #include "posixselect.h"
42
43 #if defined (HAVE_STRING_H)
44 # include <string.h>
45 #else /* !HAVE_STRING_H */
46 # include <strings.h>
47 #endif /* !HAVE_STRING_H */
48
49 #if !defined (strchr) && !defined (__STDC__)
50 extern char *strchr (), *strrchr ();
51 #endif /* !strchr && !__STDC__ */
52
53 #include "readline.h"
54 #include "rlprivate.h"
55
56 static int find_matching_open PARAMS((char *, int, int));
57
58 /* Non-zero means try to blink the matching open parenthesis when the
59 close parenthesis is inserted. */
60 #if defined (HAVE_SELECT)
61 int rl_blink_matching_paren = 1;
62 #else /* !HAVE_SELECT */
63 int rl_blink_matching_paren = 0;
64 #endif /* !HAVE_SELECT */
65
66 static int _paren_blink_usec = 500000;
67
68 /* Change emacs_standard_keymap to have bindings for paren matching when
69 ON_OR_OFF is 1, change them back to self_insert when ON_OR_OFF == 0. */
70 void
_rl_enable_paren_matching(on_or_off)71 _rl_enable_paren_matching (on_or_off)
72 int on_or_off;
73 {
74 if (on_or_off)
75 { /* ([{ */
76 rl_bind_key_in_map (')', rl_insert_close, emacs_standard_keymap);
77 rl_bind_key_in_map (']', rl_insert_close, emacs_standard_keymap);
78 rl_bind_key_in_map ('}', rl_insert_close, emacs_standard_keymap);
79 }
80 else
81 { /* ([{ */
82 rl_bind_key_in_map (')', rl_insert, emacs_standard_keymap);
83 rl_bind_key_in_map (']', rl_insert, emacs_standard_keymap);
84 rl_bind_key_in_map ('}', rl_insert, emacs_standard_keymap);
85 }
86 }
87
88 int
rl_set_paren_blink_timeout(u)89 rl_set_paren_blink_timeout (u)
90 int u;
91 {
92 int o;
93
94 o = _paren_blink_usec;
95 if (u > 0)
96 _paren_blink_usec = u;
97 return (o);
98 }
99
100 int
rl_insert_close(count,invoking_key)101 rl_insert_close (count, invoking_key)
102 int count, invoking_key;
103 {
104 if (rl_explicit_arg || !rl_blink_matching_paren)
105 _rl_insert_char (count, invoking_key);
106 else
107 {
108 #if defined (HAVE_SELECT)
109 int orig_point, match_point, ready;
110 struct timeval timer;
111 fd_set readfds;
112
113 _rl_insert_char (1, invoking_key);
114 (*rl_redisplay_function) ();
115 match_point =
116 find_matching_open (rl_line_buffer, rl_point - 2, invoking_key);
117
118 /* Emacs might message or ring the bell here, but I don't. */
119 if (match_point < 0)
120 return -1;
121
122 FD_ZERO (&readfds);
123 FD_SET (fileno (rl_instream), &readfds);
124 USEC_TO_TIMEVAL (_paren_blink_usec, timer);
125
126 orig_point = rl_point;
127 rl_point = match_point;
128 (*rl_redisplay_function) ();
129 ready = select (1, &readfds, (fd_set *)NULL, (fd_set *)NULL, &timer);
130 rl_point = orig_point;
131 #else /* !HAVE_SELECT */
132 _rl_insert_char (count, invoking_key);
133 #endif /* !HAVE_SELECT */
134 }
135 return 0;
136 }
137
138 static int
find_matching_open(string,from,closer)139 find_matching_open (string, from, closer)
140 char *string;
141 int from, closer;
142 {
143 register int i;
144 int opener, level, delimiter;
145
146 switch (closer)
147 {
148 case ']': opener = '['; break;
149 case '}': opener = '{'; break;
150 case ')': opener = '('; break;
151 default:
152 return (-1);
153 }
154
155 level = 1; /* The closer passed in counts as 1. */
156 delimiter = 0; /* Delimited state unknown. */
157
158 for (i = from; i > -1; i--)
159 {
160 if (delimiter && (string[i] == delimiter))
161 delimiter = 0;
162 else if (rl_basic_quote_characters && strchr (rl_basic_quote_characters, string[i]))
163 delimiter = string[i];
164 else if (!delimiter && (string[i] == closer))
165 level++;
166 else if (!delimiter && (string[i] == opener))
167 level--;
168
169 if (!level)
170 break;
171 }
172 return (i);
173 }
174