Source code of Windows XP (NT5)
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

331 lines
8.6 KiB

/***
*getwch.c - contains _getwch(), _getwche(), _ungetwch() for Win32
*
* Copyright (c) 1989-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* Defines the "direct console" functions listed above.
*
* NOTE: The real-mode DOS versions of these functions read from
* standard input and are therefore redirected when standard input
* is redirected. However, these versions ALWAYS read from the console,
* even when standard input is redirected.
*
*Revision History:
* 04-19-00 GB Module created based on getch.c
* 05-17-00 GB Use ERROR_CALL_NOT_IMPLEMENTED for existance of W API
*
*******************************************************************************/
#include <cruntime.h>
#include <oscalls.h>
#include <conio.h>
#include <internal.h>
#include <mtdll.h>
#include <stdio.h>
#include <stdlib.h>
#include <dbgint.h>
#include <malloc.h>
#include <wchar.h>
#include <string.h>
typedef struct {
unsigned char LeadChar;
unsigned char SecondChar;
} CharPair;
/*
* This is the one character push-back buffer used by _getwch(), _getwche()
* and _ungetwch().
*/
static wint_t wchbuf = WEOF;
static int bUseW = 2;
/*
* Declaration for console handle
*/
extern intptr_t _coninpfh;
/*
* Function that looks up the extended key code for a given event.
*/
const CharPair * __cdecl _getextendedkeycode(KEY_EVENT_RECORD *);
/***
*wint_t _getwch(), _getwche() - read one char. from console (without and with
* echo)
*
*Purpose:
* If the "_ungetwch()" push-back buffer is not empty (empty==-1) Then
* Mark it empty (-1) and RETURN the value that was in it
* Read a character using ReadConsole in RAW mode
* Return the Character Code
* _getwche(): Same as _getwch() except that the character value returned
* is echoed (via "_putwch()")
*
*Entry:
* None, reads from console.
*
*Exit:
* If an error is returned from the API
* Then WEOF
* Otherwise
* next byte from console
* Static variable "wchbuf" may be altered
*
*Exceptions:
*
*******************************************************************************/
#ifdef _MT
wint_t __cdecl _getwch (
void
)
{
wchar_t wch;
_mlock(_CONIO_LOCK); /* secure the console lock */
wch = _getwch_lk(); /* input the character */
_munlock(_CONIO_LOCK); /* release the console lock */
return wch;
}
wint_t __cdecl _getwche (
void
)
{
wchar_t wch;
_mlock(_CONIO_LOCK); /* secure the console lock */
wch = _getwche_lk(); /* input and echo the character */
_munlock(_CONIO_LOCK); /* unlock the console */
return wch;
}
#endif /* _MT */
#ifdef _MT
wint_t __cdecl _getwch_lk (
#else
wint_t __cdecl _getwch (
#endif
void
)
{
INPUT_RECORD ConInpRec;
DWORD NumRead;
const CharPair *pCP;
wchar_t wch = 0; /* single character buffer */
DWORD oldstate;
char ch;
/*
* check pushback buffer (wchbuf) a for character
*/
if ( wchbuf != WEOF ) {
/*
* something there, clear buffer and return the character.
*/
wch = (wchar_t)(wchbuf & 0xFFFF);
wchbuf = WEOF;
return wch;
}
if (_coninpfh == -1)
return WEOF;
/*
* _coninpfh, the handle to the console input, is created the first
* time that either _getwch() or _cgetws() or _kbhit() is called.
*/
if ( _coninpfh == -2 )
__initconin();
/*
* Switch to raw mode (no line input, no echo input)
*/
GetConsoleMode( (HANDLE)_coninpfh, &oldstate );
SetConsoleMode( (HANDLE)_coninpfh, 0L );
for ( ; ; ) {
/*
* Get a console input event.
*/
if ( bUseW ) {
if ( !ReadConsoleInputW( (HANDLE)_coninpfh,
&ConInpRec,
1L,
&NumRead)) {
if ( bUseW == 2 && GetLastError() == ERROR_CALL_NOT_IMPLEMENTED)
bUseW = FALSE;
else {
wch = WEOF;
break;
}
}
else
bUseW = TRUE;
if ( NumRead == 0) {
wch = WEOF;
break;
}
}
if ( !bUseW) {
if ( !ReadConsoleInputA( (HANDLE) _coninpfh,
&ConInpRec,
1L,
&NumRead )
|| (NumRead == 0)) {
wch = WEOF;
break;
}
}
/*
* Look for, and decipher, key events.
*/
if ( (ConInpRec.EventType == KEY_EVENT) &&
ConInpRec.Event.KeyEvent.bKeyDown ) {
/*
* Easy case: if uChar.AsciiChar is non-zero, just stuff it
* into wch and quit.
*/
if (bUseW) {
if ( wch = (wchar_t)ConInpRec.Event.KeyEvent.uChar.UnicodeChar )
break;
}
else {
if ( ch = ConInpRec.Event.KeyEvent.uChar.AsciiChar ) {
MultiByteToWideChar(GetConsoleCP(),
0,
&ch,
1,
&wch,
1);
break;
}
}
/*
* Hard case: either an extended code or an event which should
* not be recognized. let _getextendedkeycode() do the work...
*/
if ( pCP = _getextendedkeycode( &(ConInpRec.Event.KeyEvent) ) ) {
wch = pCP->LeadChar;
wchbuf = pCP->SecondChar;
break;
}
}
}
/*
* Restore previous console mode.
*/
SetConsoleMode( (HANDLE)_coninpfh, oldstate );
return wch;
}
/*
* getwche is just getwch followed by a putch if no error occurred
*/
#ifdef _MT
wint_t __cdecl _getwche_lk (
#else
wint_t __cdecl _getwche (
#endif
void
)
{
wchar_t wch; /* character read */
/*
* check pushback buffer (wchbuf) a for character. if found, return
* it without echoing.
*/
if ( wchbuf != WEOF ) {
/*
* something there, clear buffer and return the character.
*/
wch = (wchar_t)(wchbuf & 0xFFFF);
wchbuf = WEOF;
return wch;
}
wch = _getwch_lk(); /* read character */
if (wch != WEOF) {
if (_putwch_lk(wch) != WEOF) {
return wch; /* if no error, return char */
}
}
return WEOF; /* get or put failed, return EOF */
}
/***
*wint_t _ungetwch(c) - push back one character for "_getwch()" or "_getwche()"
*
*Purpose:
* If the Push-back buffer "wchbuf" is -1 Then
* Set "wchbuf" to the argument and return the argument
* Else
* Return EOF to indicate an error
*
*Entry:
* int c - Character to be pushed back
*
*Exit:
* If successful
* returns character that was pushed back
* Else if error
* returns EOF
*
*Exceptions:
*
*******************************************************************************/
#ifdef _MT
wint_t __cdecl _ungetwch (
wint_t c
)
{
wchar_t retval;
_mlock(_CONIO_LOCK); /* lock the console */
retval = _ungetwch_lk(c); /* pushback character */
_munlock(_CONIO_LOCK); /* unlock the console */
return retval;
}
wint_t __cdecl _ungetwch_lk (
#else
wint_t __cdecl _ungetwch (
#endif
wint_t c
)
{
/*
* Fail if the char is EOF or the pushback buffer is non-empty
*/
if ( (c == WEOF) || (wchbuf != WEOF) )
return EOF;
wchbuf = (c & 0xFF);
return wchbuf;
}