1 /* parens.c -- implementation of matching parentheses feature. */
2
3 /* Copyright (C) 1987, 1989, 1992-2015, 2017 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 int rl_blink_matching_paren = 0;
61
62 static int _paren_blink_usec = 500000;
63
64 /* Change emacs_standard_keymap to have bindings for paren matching when
65 ON_OR_OFF is 1, change them back to self_insert when ON_OR_OFF == 0. */
66 void
_rl_enable_paren_matching(int on_or_off)67 _rl_enable_paren_matching (int on_or_off)
68 {
69 if (on_or_off)
70 {
71 /* ([{ */
72 rl_bind_key_in_map (')', rl_insert_close, emacs_standard_keymap);
73 rl_bind_key_in_map (']', rl_insert_close, emacs_standard_keymap);
74 rl_bind_key_in_map ('}', rl_insert_close, emacs_standard_keymap);
75
76 #if defined (VI_MODE)
77 /* ([{ */
78 rl_bind_key_in_map (')', rl_insert_close, vi_insertion_keymap);
79 rl_bind_key_in_map (']', rl_insert_close, vi_insertion_keymap);
80 rl_bind_key_in_map ('}', rl_insert_close, vi_insertion_keymap);
81 #endif
82 }
83 else
84 {
85 /* ([{ */
86 rl_bind_key_in_map (')', rl_insert, emacs_standard_keymap);
87 rl_bind_key_in_map (']', rl_insert, emacs_standard_keymap);
88 rl_bind_key_in_map ('}', rl_insert, emacs_standard_keymap);
89
90 #if defined (VI_MODE)
91 /* ([{ */
92 rl_bind_key_in_map (')', rl_insert, vi_insertion_keymap);
93 rl_bind_key_in_map (']', rl_insert, vi_insertion_keymap);
94 rl_bind_key_in_map ('}', rl_insert, vi_insertion_keymap);
95 #endif
96 }
97 }
98
99 int
rl_set_paren_blink_timeout(int u)100 rl_set_paren_blink_timeout (int u)
101 {
102 int o;
103
104 o = _paren_blink_usec;
105 if (u > 0)
106 _paren_blink_usec = u;
107 return (o);
108 }
109
110 int
rl_insert_close(int count,int invoking_key)111 rl_insert_close (int count, int 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, ready;
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 USEC_TO_TIMEVAL (_paren_blink_usec, timer);
134
135 orig_point = rl_point;
136 rl_point = match_point;
137 (*rl_redisplay_function) ();
138 ready = select (1, &readfds, (fd_set *)NULL, (fd_set *)NULL, &timer);
139 rl_point = orig_point;
140 #else /* !HAVE_SELECT */
141 _rl_insert_char (count, invoking_key);
142 #endif /* !HAVE_SELECT */
143 }
144 return 0;
145 }
146
147 static int
find_matching_open(char * string,int from,int closer)148 find_matching_open (char *string, int from, int closer)
149 {
150 register int i;
151 int opener, level, delimiter;
152
153 switch (closer)
154 {
155 case ']': opener = '['; break;
156 case '}': opener = '{'; break;
157 case ')': opener = '('; break;
158 default:
159 return (-1);
160 }
161
162 level = 1; /* The closer passed in counts as 1. */
163 delimiter = 0; /* Delimited state unknown. */
164
165 for (i = from; i > -1; i--)
166 {
167 if (delimiter && (string[i] == delimiter))
168 delimiter = 0;
169 else if (rl_basic_quote_characters && strchr (rl_basic_quote_characters, string[i]))
170 delimiter = string[i];
171 else if (!delimiter && (string[i] == closer))
172 level++;
173 else if (!delimiter && (string[i] == opener))
174 level--;
175
176 if (!level)
177 break;
178 }
179 return (i);
180 }
181