1 /* parens.c -- Implementation of matching parentheses feature. */
2
3 /* Copyright (C) 1987, 1989, 1992 Free Software Foundation, Inc.
4
5 This file is part of the GNU Readline Library, a library for
6 reading lines of text with interactive input and history editing.
7
8 The GNU Readline Library is free software; you can redistribute it
9 and/or modify it under the terms of the GNU General Public License
10 as published by the Free Software Foundation; either version 2, or
11 (at your option) any later version.
12
13 The GNU Readline Library is distributed in the hope that it will be
14 useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15 of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 The GNU General Public License is often shipped with GNU software, and
19 is generally kept in a file called COPYING or LICENSE. If you do not
20 have a copy of the license, write to the Free Software Foundation,
21 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA. */
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_readline.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 #if defined (FD_SET) && !defined (HAVE_SELECT)
42 # define HAVE_SELECT
43 #endif
44
45 #if defined (HAVE_SELECT)
46 # include <sys/time.h>
47 #endif /* HAVE_SELECT */
48 #if defined (HAVE_SYS_SELECT_H)
49 # include <sys/select.h>
50 #endif
51
52 #if defined (HAVE_STRING_H)
53 # include <string.h>
54 #else /* !HAVE_STRING_H */
55 # include <strings.h>
56 #endif /* !HAVE_STRING_H */
57
58 #if !defined (strchr) && !defined (__STDC__)
59 extern char *strchr (), *strrchr ();
60 #endif /* !strchr && !__STDC__ */
61
62 #include "readline.h"
63 #include "rlprivate.h"
64
65 static int find_matching_open PARAMS((char *, int, int));
66
67 /* Non-zero means try to blink the matching open parenthesis when the
68 close parenthesis is inserted. */
69 #if defined (HAVE_SELECT)
70 int rl_blink_matching_paren = 1;
71 #else /* !HAVE_SELECT */
72 int rl_blink_matching_paren = 0;
73 #endif /* !HAVE_SELECT */
74
75 static int _paren_blink_usec = 500000;
76
77 /* Change emacs_standard_keymap to have bindings for paren matching when
78 ON_OR_OFF is 1, change them back to self_insert when ON_OR_OFF == 0. */
79 void
_rl_enable_paren_matching(on_or_off)80 _rl_enable_paren_matching (on_or_off)
81 int on_or_off;
82 {
83 if (on_or_off)
84 { /* ([{ */
85 rl_bind_key_in_map (')', rl_insert_close, emacs_standard_keymap);
86 rl_bind_key_in_map (']', rl_insert_close, emacs_standard_keymap);
87 rl_bind_key_in_map ('}', rl_insert_close, emacs_standard_keymap);
88 }
89 else
90 { /* ([{ */
91 rl_bind_key_in_map (')', rl_insert, emacs_standard_keymap);
92 rl_bind_key_in_map (']', rl_insert, emacs_standard_keymap);
93 rl_bind_key_in_map ('}', rl_insert, emacs_standard_keymap);
94 }
95 }
96
97 int
rl_set_paren_blink_timeout(u)98 rl_set_paren_blink_timeout (u)
99 int u;
100 {
101 int o;
102
103 o = _paren_blink_usec;
104 if (u > 0)
105 _paren_blink_usec = u;
106 return (o);
107 }
108
109 int
rl_insert_close(count,invoking_key)110 rl_insert_close (count, invoking_key)
111 int count, invoking_key;
112 {
113 if (rl_explicit_arg || !rl_blink_matching_paren)
114 _rl_insert_char (count, invoking_key);
115 else
116 {
117 #if defined (HAVE_SELECT)
118 int orig_point, match_point;
119 struct timeval timer;
120 fd_set readfds;
121
122 _rl_insert_char (1, invoking_key);
123 (*rl_redisplay_function) ();
124 match_point =
125 find_matching_open (rl_line_buffer, rl_point - 2, invoking_key);
126
127 /* Emacs might message or ring the bell here, but I don't. */
128 if (match_point < 0)
129 return -1;
130
131 FD_ZERO (&readfds);
132 FD_SET (fileno (rl_instream), &readfds);
133 timer.tv_sec = 0;
134 timer.tv_usec = _paren_blink_usec;
135
136 orig_point = rl_point;
137 rl_point = match_point;
138 (*rl_redisplay_function) ();
139 select (1, &readfds, (fd_set *)NULL, (fd_set *)NULL, &timer);
140 rl_point = orig_point;
141 #else /* !HAVE_SELECT */
142 _rl_insert_char (count, invoking_key);
143 #endif /* !HAVE_SELECT */
144 }
145 return 0;
146 }
147
148 static int
find_matching_open(string,from,closer)149 find_matching_open (string, from, closer)
150 char *string;
151 int from, closer;
152 {
153 register int i;
154 int opener, level, delimiter;
155
156 switch (closer)
157 {
158 case ']': opener = '['; break;
159 case '}': opener = '{'; break;
160 case ')': opener = '('; break;
161 default:
162 return (-1);
163 }
164
165 level = 1; /* The closer passed in counts as 1. */
166 delimiter = 0; /* Delimited state unknown. */
167
168 for (i = from; i > -1; i--)
169 {
170 if (delimiter && (string[i] == delimiter))
171 delimiter = 0;
172 else if (rl_basic_quote_characters && strchr (rl_basic_quote_characters, string[i]))
173 delimiter = string[i];
174 else if (!delimiter && (string[i] == closer))
175 level++;
176 else if (!delimiter && (string[i] == opener))
177 level--;
178
179 if (!level)
180 break;
181 }
182 return (i);
183 }
184