TestKeyDownBit函数和SetKeyDownBit函数和ClearKeyDownBit函数分析

TestKeyDownBit函数和SetKeyDownBit函数和ClearKeyDownBit函数分析

第一部分：

/*
* Two bits per VK (down & toggle) so we can pack 4 VK keystates into 1 byte:
*
*              Byte 0                           Byte 1
* .---.---.---.---.---.---.---.---. .---.---.---.---.---.---.---.---. .-- -
* | T | D | T | D | T | D | T | D | | T | D | T | D | T | D | T | D | |
* `---'---'---'---'---'---'---'---' `---'---'---'---'---'---'---'---' `-- -
* : VK 3  : VK 2  : VK 1  : VK 0  : : VK 7  : VK 6  : VK 5  : VK 4  : :
*
* KEY_BYTE(pb, vk)   identifies the byte containing the VK's state
* KEY_DOWN_BIT(vk)   identifies the VK's down bit within a byte
* KEY_TOGGLE_BIT(vk) identifies the VK's toggle bit within a byte
*/
#define KEY_BYTE(pb, vk)   pb[((BYTE)(vk)) >> 2]
#define KEY_DOWN_BIT(vk)   (1 << ((((BYTE)(vk)) & 3) << 1))
#define KEY_TOGGLE_BIT(vk) (1 << (((((BYTE)(vk)) & 3) << 1) + 1))

#define TestKeyDownBit(pb, vk)     (KEY_BYTE(pb,vk) &   KEY_DOWN_BIT(vk))
#define SetKeyDownBit(pb, vk)      (KEY_BYTE(pb,vk) |=  KEY_DOWN_BIT(vk))
#define ClearKeyDownBit(pb, vk)    (KEY_BYTE(pb,vk) &= ~KEY_DOWN_BIT(vk))
#define TestKeyToggleBit(pb, vk)   (KEY_BYTE(pb,vk) &   KEY_TOGGLE_BIT(vk))
#define SetKeyToggleBit(pb, vk)    (KEY_BYTE(pb,vk) |=  KEY_TOGGLE_BIT(vk))
#define ClearKeyToggleBit(pb, vk)  (KEY_BYTE(pb,vk) &= ~KEY_TOGGLE_BIT(vk))
#define ToggleKeyToggleBit(pb, vk) (KEY_BYTE(pb,vk) ^=  KEY_TOGGLE_BIT(vk))

第二部分：

chenghao@chenghaodeiMac public % grep "KEY_DOWN_BIT" -nr
./internal/windows/inc/winuserp.h:2553: * KEY_DOWN_BIT(vk)   identifies the VK's down bit within a byte
./internal/windows/inc/winuserp.h:2557:#define KEY_DOWN_BIT(vk)   (1 << ((((BYTE)(vk)) & 3) << 1))
./internal/windows/inc/winuserp.h:2560:#define TestKeyDownBit(pb, vk)     (KEY_BYTE(pb,vk) &   KEY_DOWN_BIT(vk))
./internal/windows/inc/winuserp.h:2561:#define SetKeyDownBit(pb, vk)      (KEY_BYTE(pb,vk) |=  KEY_DOWN_BIT(vk))
./internal/windows/inc/winuserp.h:2562:#define ClearKeyDownBit(pb, vk)    (KEY_BYTE(pb,vk) &= ~KEY_DOWN_BIT(vk))

#define VK_CLEAR          0x0C
#define VK_RETURN         0x0D

#define VK_SHIFT          0x10
#define VK_CONTROL        0x11
#define VK_MENU           0x12        10010        
#define VK_PAUSE          0x13
#define VK_CAPITAL        0x14

#define KEY_BYTE(pb, vk)   pb[((BYTE)(vk)) >> 2]
#define KEY_DOWN_BIT(vk)   (1 << ((((BYTE)(vk)) & 3) << 1))

10000    100        0        0                   0x1

10001    100        10         100            0x4    

10010    100        100        10000        0x10

10011    100        110        1000000        040

#define VK_SHIFT          0x10
#define VK_CONTROL        0x11
#define VK_MENU           0x12        10010        
#define VK_PAUSE          0x13

上面四个键可以共用1个字节，所以要除以4，也就是右移2位！！！：    #define KEY_BYTE(pb, vk)   pb[((BYTE)(vk)) >> 2]

VOID UpdateRawKeyState(
BYTE Vk,
BOOL fBreak)
{
CheckCritIn();

    if (fBreak) {
ClearRawKeyDown(Vk);
} else {

        /*
* This is a key make.  If the key was not already down, update the
* physical toggle bit.
*/
if (!TestRawKeyDown(Vk)) {
ToggleRawKeyToggle(Vk);
}

        /*
* This is a make, so turn on the physical key down bit.
*/
SetRawKeyDown(Vk);
}
}

VOID xxxProcessKeyEvent(
PKE pke,
ULONG_PTR ExtraInformation,
BOOL bInjected)
{

if (KOREAN_KBD_LAYOUT(GetActiveHKL())) {
if ((pke->usFlaggedVk & KBDBREAK) &&
!(pke->usFlaggedVk & KBDUNICODE) &&
(pke->bScanCode == 0xF1 || pke->bScanCode == 0xF2) &&
!TestRawKeyDown(Vk)) {
/*
* This is actually a keydown with a scancode of 0xF1 or 0xF2 from a
* Korean keyboard. Korean IMEs and apps want a WM_KEYDOWN with a
* scancode of 0xF1 or 0xF2. They don't mind not getting the WM_KEYUP.
* Don't update physical keystate to allow a real 0x71/0x72 keydown.
*/
pke->usFlaggedVk &= ~KBDBREAK;
} else {
UpdateRawKeyState(Vk, pke->usFlaggedVk & KBDBREAK);
}
} else {
UpdateRawKeyState(Vk, pke->usFlaggedVk & KBDBREAK);
}

    /*
* Convert Left/Right Ctrl/Shift/Alt key to "unhanded" key.
* ie: if VK_LCONTROL or VK_RCONTROL, convert to VK_CONTROL etc.
*/
if ((Vk >= VK_LSHIFT) && (Vk <= VK_RMENU)) {
Vk = (BYTE)((Vk - VK_LSHIFT) / 2 + VK_SHIFT);
UpdateRawKeyState(Vk, pke->usFlaggedVk & KBDBREAK);
}

第三部分：

/public/sdk/inc/winuser.h

/*
* Virtual Keys, Standard Set
*/
#define VK_LBUTTON        0x01
#define VK_RBUTTON        0x02
#define VK_CANCEL         0x03
#define VK_MBUTTON        0x04    /* NOT contiguous with L & RBUTTON */

#if(_WIN32_WINNT >= 0x0500)
#define VK_XBUTTON1       0x05    /* NOT contiguous with L & RBUTTON */
#define VK_XBUTTON2       0x06    /* NOT contiguous with L & RBUTTON */
#endif /* _WIN32_WINNT >= 0x0500 */

/*
* 0x07 : unassigned
*/

#define VK_BACK           0x08
#define VK_TAB            0x09

/*
* 0x0A - 0x0B : reserved
*/