1 /* $NetBSD: ttyin.c,v 1.3 2013/09/04 19:44:21 tron Exp $ */
2
3 /*
4 * Copyright (C) 1984-2012 Mark Nudelman
5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Less License, as specified in the README file.
8 *
9 * For more information, see the README file.
10 */
11
12
13 /*
14 * Routines dealing with getting input from the keyboard (i.e. from the user).
15 */
16
17 #include "less.h"
18 #if OS2
19 #include "cmd.h"
20 #include "pckeys.h"
21 #endif
22 #if MSDOS_COMPILER==WIN32C
23 #include "windows.h"
24 extern char WIN32getch();
25 static DWORD console_mode;
26 #endif
27
28 public int tty;
29 extern int sigs;
30 extern int utf_mode;
31
32 /*
33 * Open keyboard for input.
34 */
35 public void
open_getchr()36 open_getchr()
37 {
38 #if MSDOS_COMPILER==WIN32C
39 /* Need this to let child processes inherit our console handle */
40 SECURITY_ATTRIBUTES sa;
41 memset(&sa, 0, sizeof(SECURITY_ATTRIBUTES));
42 sa.nLength = sizeof(SECURITY_ATTRIBUTES);
43 sa.bInheritHandle = TRUE;
44 tty = (int) CreateFile("CONIN$", GENERIC_READ,
45 FILE_SHARE_READ, &sa,
46 OPEN_EXISTING, 0L, NULL);
47 GetConsoleMode((HANDLE)tty, &console_mode);
48 /* Make sure we get Ctrl+C events. */
49 SetConsoleMode((HANDLE)tty, ENABLE_PROCESSED_INPUT);
50 #else
51 #if MSDOS_COMPILER
52 extern int fd0;
53 /*
54 * Open a new handle to CON: in binary mode
55 * for unbuffered keyboard read.
56 */
57 fd0 = dup(0);
58 close(0);
59 tty = open("CON", OPEN_READ);
60 #if MSDOS_COMPILER==DJGPPC
61 /*
62 * Setting stdin to binary causes Ctrl-C to not
63 * raise SIGINT. We must undo that side-effect.
64 */
65 (void) __djgpp_set_ctrl_c(1);
66 #endif
67 #else
68 /*
69 * Try /dev/tty.
70 * If that doesn't work, use file descriptor 2,
71 * which in Unix is usually attached to the screen,
72 * but also usually lets you read from the keyboard.
73 */
74 #if OS2
75 /* The __open() system call translates "/dev/tty" to "con". */
76 tty = __open("/dev/tty", OPEN_READ);
77 #else
78 tty = open("/dev/tty", OPEN_READ);
79 #endif
80 if (tty < 0)
81 tty = 2;
82 #endif
83 #endif
84 }
85
86 /*
87 * Close the keyboard.
88 */
89 public void
close_getchr()90 close_getchr()
91 {
92 #if MSDOS_COMPILER==WIN32C
93 SetConsoleMode((HANDLE)tty, console_mode);
94 CloseHandle((HANDLE)tty);
95 #endif
96 }
97
98 /*
99 * Get a character from the keyboard.
100 */
101 public int
getchr()102 getchr()
103 {
104 char c;
105 int result;
106
107 do
108 {
109 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
110 /*
111 * In raw read, we don't see ^C so look here for it.
112 */
113 flush();
114 #if MSDOS_COMPILER==WIN32C
115 if (ABORT_SIGS())
116 return (READ_INTR);
117 c = WIN32getch(tty);
118 #else
119 c = getch();
120 #endif
121 result = 1;
122 if (c == '\003')
123 return (READ_INTR);
124 #else
125 result = iread(tty, &c, sizeof(char));
126 if (result == READ_INTR)
127 return (READ_INTR);
128 if (result < 0)
129 {
130 /*
131 * Don't call error() here,
132 * because error calls getchr!
133 */
134 quit(QUIT_ERROR);
135 }
136 #endif
137 #if 0 /* allow entering arbitrary hex chars for testing */
138 /* ctrl-A followed by two hex chars makes a byte */
139 {
140 int hex_in = 0;
141 int hex_value = 0;
142 if (c == CONTROL('A'))
143 {
144 hex_in = 2;
145 result = 0;
146 continue;
147 }
148 if (hex_in > 0)
149 {
150 int v;
151 if (c >= '0' && c <= '9')
152 v = c - '0';
153 else if (c >= 'a' && c <= 'f')
154 v = c - 'a' + 10;
155 else if (c >= 'A' && c <= 'F')
156 v = c - 'A' + 10;
157 else
158 hex_in = 0;
159 hex_value = (hex_value << 4) | v;
160 if (--hex_in > 0)
161 {
162 result = 0;
163 continue;
164 }
165 c = hex_value;
166 }
167 }
168 #endif
169 /*
170 * Various parts of the program cannot handle
171 * an input character of '\0'.
172 * If a '\0' was actually typed, convert it to '\340' here.
173 */
174 if (c == '\0')
175 c = '\340';
176 } while (result != 1);
177
178 return (c & 0xFF);
179 }
180