1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 2008 Rob Landley <rob@landley.net>
* Copyright (C) 2008 Denys Vlasenko <vda.linux@googlemail.com>
*
* Licensed under GPL version 2, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
int64_t FAST_FUNC read_key(int fd, char *buffer)
{
struct pollfd pfd;
const char *seq;
int n;
int c;
/* Known escape sequences for cursor and function keys */
static const char esccmds[] ALIGN1 = {
'O','A' |0x80,KEYCODE_UP ,
'O','B' |0x80,KEYCODE_DOWN ,
'O','C' |0x80,KEYCODE_RIGHT ,
'O','D' |0x80,KEYCODE_LEFT ,
'O','H' |0x80,KEYCODE_HOME ,
'O','F' |0x80,KEYCODE_END ,
#if 0
'O','P' |0x80,KEYCODE_FUN1 ,
/* [ESC] ESC O [2] P - [Alt-][Shift-]F1 */
/* Ctrl- seems to not affect sequences */
'O','Q' |0x80,KEYCODE_FUN2 ,
'O','R' |0x80,KEYCODE_FUN3 ,
'O','S' |0x80,KEYCODE_FUN4 ,
#endif
'[','A' |0x80,KEYCODE_UP ,
'[','B' |0x80,KEYCODE_DOWN ,
'[','C' |0x80,KEYCODE_RIGHT ,
'[','D' |0x80,KEYCODE_LEFT ,
/* ESC [ 1 ; 2 x, where x = A/B/C/D: Shift-<arrow> */
/* ESC [ 1 ; 3 x, where x = A/B/C/D: Alt-<arrow> */
/* ESC [ 1 ; 4 x, where x = A/B/C/D: Alt-Shift-<arrow> */
/* ESC [ 1 ; 5 x, where x = A/B/C/D: Ctrl-<arrow> - implemented below */
/* ESC [ 1 ; 6 x, where x = A/B/C/D: Ctrl-Shift-<arrow> */
'[','H' |0x80,KEYCODE_HOME , /* xterm */
/* [ESC] ESC [ [2] H - [Alt-][Shift-]Home */
'[','F' |0x80,KEYCODE_END , /* xterm */
'[','1','~' |0x80,KEYCODE_HOME , /* vt100? linux vt? or what? */
'[','2','~' |0x80,KEYCODE_INSERT ,
/* ESC [ 2 ; 3 ~ - Alt-Insert */
'[','3','~' |0x80,KEYCODE_DELETE ,
/* [ESC] ESC [ 3 [;2] ~ - [Alt-][Shift-]Delete */
/* ESC [ 3 ; 3 ~ - Alt-Delete */
/* ESC [ 3 ; 5 ~ - Ctrl-Delete */
'[','4','~' |0x80,KEYCODE_END , /* vt100? linux vt? or what? */
'[','5','~' |0x80,KEYCODE_PAGEUP ,
/* ESC [ 5 ; 3 ~ - Alt-PgUp */
/* ESC [ 5 ; 5 ~ - Ctrl-PgUp */
/* ESC [ 5 ; 7 ~ - Ctrl-Alt-PgUp */
'[','6','~' |0x80,KEYCODE_PAGEDOWN,
'[','7','~' |0x80,KEYCODE_HOME , /* vt100? linux vt? or what? */
'[','8','~' |0x80,KEYCODE_END , /* vt100? linux vt? or what? */
#if 0
'[','1','1','~'|0x80,KEYCODE_FUN1 ,
'[','1','2','~'|0x80,KEYCODE_FUN2 ,
'[','1','3','~'|0x80,KEYCODE_FUN3 ,
'[','1','4','~'|0x80,KEYCODE_FUN4 ,
'[','1','5','~'|0x80,KEYCODE_FUN5 ,
/* [ESC] ESC [ 1 5 [;2] ~ - [Alt-][Shift-]F5 */
'[','1','7','~'|0x80,KEYCODE_FUN6 ,
'[','1','8','~'|0x80,KEYCODE_FUN7 ,
'[','1','9','~'|0x80,KEYCODE_FUN8 ,
'[','2','0','~'|0x80,KEYCODE_FUN9 ,
'[','2','1','~'|0x80,KEYCODE_FUN10 ,
'[','2','3','~'|0x80,KEYCODE_FUN11 ,
'[','2','4','~'|0x80,KEYCODE_FUN12 ,
#endif
'[','1',';','5','A' |0x80,KEYCODE_CTRL_UP ,
'[','1',';','5','B' |0x80,KEYCODE_CTRL_DOWN ,
'[','1',';','5','C' |0x80,KEYCODE_CTRL_RIGHT,
'[','1',';','5','D' |0x80,KEYCODE_CTRL_LEFT ,
0
};
errno = 0;
n = (unsigned char) *buffer++;
if (n == 0) {
/* If no data, block waiting for input.
* It is tempting to read more than one byte here,
* but it breaks pasting. Example: at shell prompt,
* user presses "c","a","t" and then pastes "\nline\n".
* When we were reading 3 bytes here, we were eating
* "li" too, and cat was getting wrong input.
*/
n = safe_read(fd, buffer, 1);
if (n <= 0)
return -1;
}
/* Grab character to return from buffer */
c = (unsigned char)buffer[0];
n--;
if (n)
memmove(buffer, buffer + 1, n);
/* Only ESC starts ESC sequences */
if (c != 27)
goto ret;
/* Loop through known ESC sequences */
pfd.fd = fd;
pfd.events = POLLIN;
seq = esccmds;
while (*seq != '\0') {
/* n - position in sequence we did not read yet */
int i = 0; /* position in sequence to compare */
/* Loop through chars in this sequence */
while (1) {
/* So far escape sequence matched up to [i-1] */
if (n <= i) {
/* Need more chars, read another one if it wouldn't block.
* Note that escape sequences come in as a unit,
* so if we block for long it's not really an escape sequence.
* Timeout is needed to reconnect escape sequences
* split up by transmission over a serial console. */
if (safe_poll(&pfd, 1, 50) == 0) {
/* No more data!
* Array is sorted from shortest to longest,
* we can't match anything later in array,
* break out of both loops. */
goto ret;
}
errno = 0;
if (safe_read(fd, buffer + n, 1) <= 0) {
/* If EAGAIN, then fd is O_NONBLOCK and poll lied:
* in fact, there is no data. */
if (errno != EAGAIN)
c = -1; /* otherwise it's EOF/error */
goto ret;
}
n++;
}
if (buffer[i] != (seq[i] & 0x7f)) {
/* This seq doesn't match, go to next */
seq += i;
/* Forward to last char */
while (!(*seq & 0x80))
seq++;
/* Skip it and the keycode which follows */
seq += 2;
break;
}
if (seq[i] & 0x80) {
/* Entire seq matched */
c = (signed char)seq[i+1];
n = 0;
/* n -= i; memmove(...);
* would be more correct,
* but we never read ahead that much,
* and n == i here. */
goto ret;
}
i++;
}
}
/* We did not find matching sequence, it was a bare ESC.
* We possibly read and stored more input in buffer[] by now. */
/* Try to decipher "ESC [ NNN ; NNN R" sequence */
if (ENABLE_FEATURE_EDITING_ASK_TERMINAL
&& n != 0
&& buffer[0] == '['
) {
char *end;
unsigned long row, col;
while (n < KEYCODE_BUFFER_SIZE-1) { /* 1 for cnt */
if (safe_poll(&pfd, 1, 50) == 0) {
/* No more data! */
break;
}
errno = 0;
if (safe_read(fd, buffer + n, 1) <= 0) {
/* If EAGAIN, then fd is O_NONBLOCK and poll lied:
* in fact, there is no data. */
if (errno != EAGAIN)
c = -1; /* otherwise it's EOF/error */
goto ret;
}
if (buffer[n++] == 'R')
goto got_R;
}
goto ret;
got_R:
if (!isdigit(buffer[1]))
goto ret;
row = strtoul(buffer + 1, &end, 10);
if (*end != ';' || !isdigit(end[1]))
goto ret;
col = strtoul(end + 1, &end, 10);
if (*end != 'R')
goto ret;
if (row < 1 || col < 1 || (row | col) > 0x7fff)
goto ret;
buffer[-1] = 0;
/* Pack into "1 <row15bits> <col16bits>" 32-bit sequence */
c = (((-1 << 15) | row) << 16) | col;
/* Return it in high-order word */
return ((int64_t) c << 32) | (uint32_t)KEYCODE_CURSOR_POS;
}
ret:
buffer[-1] = n;
return c;
}
|
