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
|
/*
* Copyright (C) 1984-2009 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information about less, or for information on how to
* contact the author, see the README file.
*/
/*
* Routines dealing with getting input from the keyboard (i.e. from the user).
*/
#include "less.h"
#if OS2
#include "cmd.h"
#include "pckeys.h"
#endif
#if MSDOS_COMPILER==WIN32C
#include "windows.h"
extern char WIN32getch();
static DWORD console_mode;
#endif
public int tty;
extern int sigs;
extern int utf_mode;
/*
* Open keyboard for input.
*/
public void
open_getchr()
{
#if MSDOS_COMPILER==WIN32C
/* Need this to let child processes inherit our console handle */
SECURITY_ATTRIBUTES sa;
memset(&sa, 0, sizeof(SECURITY_ATTRIBUTES));
sa.nLength = sizeof(SECURITY_ATTRIBUTES);
sa.bInheritHandle = TRUE;
tty = (int) CreateFile("CONIN$", GENERIC_READ,
FILE_SHARE_READ, &sa,
OPEN_EXISTING, 0L, NULL);
GetConsoleMode((HANDLE)tty, &console_mode);
/* Make sure we get Ctrl+C events. */
SetConsoleMode((HANDLE)tty, ENABLE_PROCESSED_INPUT);
#else
#if MSDOS_COMPILER
extern int fd0;
/*
* Open a new handle to CON: in binary mode
* for unbuffered keyboard read.
*/
fd0 = dup(0);
close(0);
tty = open("CON", OPEN_READ);
#if MSDOS_COMPILER==DJGPPC
/*
* Setting stdin to binary causes Ctrl-C to not
* raise SIGINT. We must undo that side-effect.
*/
(void) __djgpp_set_ctrl_c(1);
#endif
#else
/*
* Try /dev/tty.
* If that doesn't work, use file descriptor 2,
* which in Unix is usually attached to the screen,
* but also usually lets you read from the keyboard.
*/
#if OS2
/* The __open() system call translates "/dev/tty" to "con". */
tty = __open("/dev/tty", OPEN_READ);
#else
tty = open("/dev/tty", OPEN_READ);
#endif
if (tty < 0)
tty = 2;
#endif
#endif
}
/*
* Close the keyboard.
*/
public void
close_getchr()
{
#if MSDOS_COMPILER==WIN32C
SetConsoleMode((HANDLE)tty, console_mode);
CloseHandle((HANDLE)tty);
#endif
}
/*
* Get a character from the keyboard.
*/
public int
getchr()
{
char c;
int result;
do
{
#if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
/*
* In raw read, we don't see ^C so look here for it.
*/
flush();
#if MSDOS_COMPILER==WIN32C
if (ABORT_SIGS())
return (READ_INTR);
c = WIN32getch(tty);
#else
c = getch();
#endif
result = 1;
if (c == '\003')
return (READ_INTR);
#else
result = iread(tty, &c, sizeof(char));
if (result == READ_INTR)
return (READ_INTR);
if (result < 0)
{
/*
* Don't call error() here,
* because error calls getchr!
*/
quit(QUIT_ERROR);
}
#endif
#if 0 /* allow entering arbitrary hex chars for testing */
/* ctrl-A followed by two hex chars makes a byte */
{
int hex_in = 0;
int hex_value = 0;
if (c == CONTROL('A'))
{
hex_in = 2;
result = 0;
continue;
}
if (hex_in > 0)
{
int v;
if (c >= '0' && c <= '9')
v = c - '0';
else if (c >= 'a' && c <= 'f')
v = c - 'a' + 10;
else if (c >= 'A' && c <= 'F')
v = c - 'A' + 10;
else
hex_in = 0;
hex_value = (hex_value << 4) | v;
if (--hex_in > 0)
{
result = 0;
continue;
}
c = hex_value;
}
}
#endif
/*
* Various parts of the program cannot handle
* an input character of '\0'.
* If a '\0' was actually typed, convert it to '\340' here.
*/
if (c == '\0')
c = '\340';
} while (result != 1);
return (c & 0xFF);
}
|
