gendriver.cpp

GenDriver即簡單的資料流驅動程式

#include <windows.h>                 // For all that Windows stuff
#include "GenDriver.h"               // Local program includes

//
// Globals
//
HINSTANCE hInst;                     // DLL instance handle

//
// Debug zone support
//
#ifdef DEBUG
// Used as a prefix string for all debug zone messages.
#define DTAG        TEXT ("GENDrv: ")

// Debug zone constants
#define ZONE_ERROR      DEBUGZONE(0)
#define ZONE_WARNING    DEBUGZONE(1)
#define ZONE_FUNC       DEBUGZONE(2)
#define ZONE_INIT       DEBUGZONE(3)
#define ZONE_DRVCALLS   DEBUGZONE(4)
#define ZONE_EXENTRY  (ZONE_FUNC | ZONE_DRVCALLS)

// Debug zone structure
DBGPARAM dpCurSettings = {
    TEXT("GenDriver"), {
    TEXT("Errors"),TEXT("Warnings"),TEXT("Functions"),
    TEXT("Init"),TEXT("Driver Calls"),TEXT("Undefined"),
    TEXT("Undefined"),TEXT("Undefined"), TEXT("Undefined"),
    TEXT("Undefined"),TEXT("Undefined"),TEXT("Undefined"),
    TEXT("Undefined"),TEXT("Undefined"),TEXT("Undefined"),
    TEXT("Undefined") },
    0x0003
};
#endif //DEBUG

//======================================================================
// DllMain - DLL initialization entry point
//
BOOL WINAPI DllMain (HANDLE hinstDLL, DWORD dwReason, 
                     LPVOID lpvReserved) {
    hInst = (HINSTANCE)hinstDLL;

    switch (dwReason) {
        case DLL_PROCESS_ATTACH:
            DEBUGREGISTER(hInst);
            // Improve performance by passing on thread attach calls
            DisableThreadLibraryCalls (hInst);
        break;
    
        case DLL_PROCESS_DETACH:
            DEBUGMSG(ZONE_INIT, (DTAG TEXT("DLL_PROCESS_DETACH\r\n")));
            break;
    }
    return TRUE;
}
//======================================================================
// GEN_Init - Driver initialization function
//
#if (_WIN32_WCE_ > 300)
DWORD GEN_Init (DWORD dwContext, LPCVOID lpvBusContext) {
#else
DWORD GEN_Init (DWORD dwContext) {
#endif
    PDRVCONTEXT pDrv;

    DEBUGMSG (ZONE_INIT | ZONE_EXENTRY, 
              (DTAG TEXT("GEN_Init++ dwContex:%x\r\n"), dwContext));

    // Allocate a drive instance structure.
    pDrv = (PDRVCONTEXT)LocalAlloc (LPTR, sizeof (DRVCONTEXT));
    if (pDrv) {
       // Initialize structure.
       memset ((PBYTE) pDrv, 0, sizeof (DRVCONTEXT));
       pDrv->dwSize = sizeof (DRVCONTEXT);

       // Read registry to determine the size of the disk.
       GetConfigData (dwContext);
    } else 
        DEBUGMSG (ZONE_INIT | ZONE_ERROR, 
                  (DTAG TEXT("GEN_Init failure. Out of memory\r\n")));
    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_Init-- pDrv: %x\r\n"), pDrv));
    return (DWORD)pDrv;
}
//======================================================================
// GEN_Deinit - Driver de-initialization function
//
BOOL GEN_Deinit (DWORD dwContext) {
    PDRVCONTEXT pDrv = (PDRVCONTEXT) dwContext;

    DEBUGMSG (ZONE_EXENTRY, 
              (DTAG TEXT("GEN_Deinit++ dwContex:%x\r\n"), dwContext));

    if (pDrv && (pDrv->dwSize == sizeof (DRVCONTEXT))) {

        // Free the driver state buffer.
        LocalFree ((PBYTE)pDrv);
    }
    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_Deinit--\r\n")));
    return TRUE;
}
//======================================================================
// GEN_Open - Called when driver opened
//
DWORD GEN_Open (DWORD dwContext, DWORD dwAccess, DWORD dwShare) {
    PDRVCONTEXT pDrv = (PDRVCONTEXT) dwContext;

    DEBUGMSG (ZONE_EXENTRY, 
              (DTAG TEXT("GEN_Open++ dwContext: %x\r\n"), dwContext));

    // Verify that the context handle is valid.
    if (pDrv && (pDrv->dwSize != sizeof (DRVCONTEXT))) {
        DEBUGMSG (ZONE_ERROR, (DTAG TEXT("GEN_Open failed\r\n")));
        return 0;
    }
    // Count the number of opens.
    InterlockedIncrement ((long *)&pDrv->nNumOpens);
    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_Open--\r\n")));
    return (DWORD)pDrv;
}
//======================================================================
// GEN_Close - Called when driver closed
//
BOOL GEN_Close (DWORD dwOpen) {
    PDRVCONTEXT pDrv = (PDRVCONTEXT) dwOpen;

    DEBUGMSG (ZONE_EXENTRY, 
              (DTAG TEXT("GEN_Close++ dwOpen: %x\r\n"), dwOpen));

    if (pDrv && (pDrv->dwSize != sizeof (DRVCONTEXT))) {
        DEBUGMSG (ZONE_FUNC | ZONE_ERROR, 
                  (DTAG TEXT("GEN_Close failed\r\n")));
        return 0;
    }
    if (pDrv->nNumOpens)
        pDrv->nNumOpens--;
    
    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_Close--\r\n")));
    return TRUE;
}
//======================================================================
// GEN_Read - Called when driver read
//
DWORD GEN_Read (DWORD dwOpen, LPVOID pBuffer, DWORD dwCount) {
    DWORD dwBytesRead = 0;
    DEBUGMSG (ZONE_EXENTRY, 
              (DTAG TEXT("GEN_Read++ dwOpen: %x\r\n"), dwOpen));

    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_Read--\r\n")));
    return dwBytesRead;
}
//======================================================================
// GEN_Write - Called when driver written
//
DWORD GEN_Write (DWORD dwOpen, LPVOID pBuffer, DWORD dwCount) {
    DWORD dwBytesWritten = 0;
    DEBUGMSG (ZONE_EXENTRY, 
              (DTAG TEXT("GEN_Write++ dwOpen: %x\r\n"), dwOpen));

    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_Write--\r\n")));
    return dwBytesWritten;
}
//======================================================================
// GEN_Seek - Called when SetFilePtr called
//
DWORD GEN_Seek (DWORD dwOpen, long lDelta, WORD wType) {
    DEBUGMSG (ZONE_EXENTRY,(DTAG TEXT("GEN_Seek++ dwOpen:%x %d %d\r\n"), 
              dwOpen, lDelta, wType));

    DEBUGMSG (ZONE_EXENTRY, (DTAG TEXT("GEN_Seek--\r\n")));
    return 0;
}
//======================================================================
// GEN_IOControl - Called when DeviceIOControl called
//
DWORD GEN_IOControl (DWORD dwOpen, DWORD dwCode, PBYTE pIn, DWORD dwIn,
                     PBYTE pOut, DWORD dwOut, DWORD *pdwBytesWritten) {
    PDRVCONTEXT pState;
    DWORD err = ERROR_INVALID_PARAMETER;

    DEBUGMSG (ZONE_EXENTRY, 
              (DTAG TEXT("GEN_IOControl++ dwOpen: %x  dwCode: %x\r\n"),
              dwOpen, dwCode));

    pState = (PDRVCONTEXT) dwOpen;
    switch (dwCode) {
        // Insert IOCTL codes here.

        default:
            DEBUGMSG (ZONE_ERROR, 
             (DTAG TEXT("GEN_IOControl: unknown code %x\r\n"), dwCode));
            return FALSE;
    }
    SetLastError (err);
    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GEN_IOControl--\r\n")));
    return TRUE;
}
//======================================================================
// GEN_PowerDown - Called when system suspends
//
// NOTE: No kernel calls, including debug messages, can be made from
// this call.
//
void GEN_PowerDown (DWORD dwContext) {
    return;
}
//======================================================================
// GEN_PowerUp - Called when resumes
//
// NOTE: No kernel calls, including debug messages, can be made from
// this call.
//
void GEN_PowerUp (DWORD dwContext) {
    return;
}
//----------------------------------------------------------------------
// GetConfigData - Get the configuration data from the registry.
//
DWORD GetConfigData (DWORD dwContext) {
    int nLen, rc;
    DWORD dwLen, dwType, dwSize = 0;
    HKEY hKey;
    TCHAR szKeyName[256], szPrefix[8];

    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GetConfigData++\r\n")));
    nLen = 0;
    // If ptr < 65K, it's a value, not a pointer.  
    if (dwContext < 0x10000) {
        return -1; 
    } else {
        __try {
            nLen = lstrlen ((LPTSTR)dwContext);
        }
        __except (EXCEPTION_EXECUTE_HANDLER) {
            nLen = 0;
        }
    }
    if (!nLen) {
        DEBUGMSG (ZONE_ERROR, (DTAG TEXT("dwContext not a ptr\r\n")));
        return -2;
    }
    // Open the Active key for the driver.
    rc = RegOpenKeyEx(HKEY_LOCAL_MACHINE,(LPTSTR)dwContext,0, 0, &hKey);

    if (rc == ERROR_SUCCESS) {
        // Read the key value.
        dwLen = sizeof(szKeyName);
        rc = RegQueryValueEx (hKey, TEXT("Key"), NULL, &dwType,
                                   (PBYTE)szKeyName, &dwLen);

        RegCloseKey(hKey);
        if (rc == ERROR_SUCCESS)
            rc = RegOpenKeyEx (HKEY_LOCAL_MACHINE, (LPTSTR) 
                                   dwContext, 0, 0, &hKey);
        if (rc == ERROR_SUCCESS) {
            // This driver doesn't need any data from the key, so as
            // an example, it just reads the Prefix value, which 
            // identifies the three-char prefix (GEN) of this driver.
            dwLen = sizeof (szPrefix);
            rc = RegQueryValueEx (hKey, TEXT("Prefix"), NULL,
                                  &dwType, (PBYTE)szPrefix, &dwLen);
            RegCloseKey(hKey);

        } else 
            DEBUGMSG (ZONE_ERROR, (TEXT("Error opening key\r\n")));
    } else
        DEBUGMSG (ZONE_ERROR, (TEXT("Error opening Active key\r\n")));

    DEBUGMSG (ZONE_FUNC, (DTAG TEXT("GetConfigData--\r\n")));
    return 0;
}