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/*
* Copyright (C) 1984-2011 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 volatile sig_atomic_t 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);
}
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