#include <windows.h>
#include "debug.h"
#include "kernelmisc.h"

BOOL ReadRegistryString(HKEY hRoot, LPTSTR devicekey, LPTSTR valname, TCHAR *strval, int maxlen)
{
    HKEY hDevkey;
    DWORD rc= RegOpenKeyEx(hRoot, devicekey, 0, 0, &hDevkey);
    if (rc) {
        debug("RegOpenKeyEx(%ls): ERROR %08lx\n", devicekey, rc);
        return FALSE;
    }

    DWORD valtype=0;
    DWORD maxsize= sizeof(TCHAR)*(maxlen-1);
    rc= RegQueryValueEx(hDevkey, valname, NULL, &valtype, (LPBYTE)strval, &maxsize);
    if (rc) {
        debug("RegQueryValueEx('%ls', '%ls', string(%d)): ERROR %08lx\n", devicekey, valname, maxlen, rc);
        RegCloseKey(hDevkey);
        return FALSE;
    }
    strval[maxlen-1]=0;
    RegCloseKey(hDevkey);
    return TRUE;
}
BOOL ReadRegistryDword(HKEY hRoot, LPTSTR devicekey, LPTSTR valname, DWORD *pvalue)
{
    HKEY hDevkey;
    DWORD rc= RegOpenKeyEx(hRoot, devicekey, 0, 0, &hDevkey);
    if (rc) {
        debug("RegOpenKeyEx(%ls): ERROR %08lx\n", devicekey, rc);
        return FALSE;
    }

    DWORD valtype=0;
    DWORD maxsize= sizeof(DWORD);
    rc= RegQueryValueEx(hDevkey, valname, NULL, &valtype, (LPBYTE)pvalue, &maxsize);
    if (rc) {
        debug("RegQueryValueEx('%ls', '%ls', DWORD): ERROR %08lx\n", devicekey, valname, rc);
        RegCloseKey(hDevkey);
        return FALSE;
    }
    RegCloseKey(hDevkey);
    return TRUE;
}
bool FindDevKey(const TCHAR *devname, TCHAR *devkey)
{
    HKEY hBuiltIn;
    LONG rc= RegOpenKeyEx(HKEY_LOCAL_MACHINE, _T("Drivers\\BuiltIn"), 0, 0, &hBuiltIn);
    if (rc) {
        error("RegOpenKeyEx");
        return NULL;
    }
    bool bRes= false;
    devkey[0]=0;
    int i=0;
    while (true) {
        TCHAR keyname[16];
        DWORD keylen=15;
        rc=RegEnumKeyEx(hBuiltIn, i++, keyname, &keylen, NULL, NULL, NULL, NULL);
        if (rc==ERROR_NO_MORE_ITEMS)
            break;
        else if (rc) {
            error("RegEnumKeyEx");
            continue;
        }
        debug("testing %d - %ls\n", i, keyname);
        TCHAR prefix[16];
        DWORD devidx=0;
        if (ReadRegistryString(hBuiltIn, keyname, _T("Prefix"), prefix, 16)
                && _tcsncmp(prefix, devname, _tcslen(prefix))==0
                && ReadRegistryDword(hBuiltIn, keyname, _T("Index"), &devidx)
                && devidx == _tcstoul(devname+_tcslen(prefix),0,10))
        {
            debug("FOUND\n");
            _tcscpy(devkey, _T("Drivers\\BuiltIn\\"));
            _tcscat(devkey, keyname);
            bRes= true;
            break;
        }
    }
    RegCloseKey(hBuiltIn);
    return bRes;
}
int WINAPI WinMain( HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPTSTR    lpCmdLine,
                   int       nCmdShow)
{
    DebugSetLogfile("loaddev.log");
    TCHAR devkey[260];
    if (!FindDevKey(lpCmdLine, devkey)) {
        debug("error finding dev handle for %ls\n", lpCmdLine);
        return 1;
    }
    KernelMode _km;
    debug("activating dev %ls\n", devkey);
    HANDLE hDev= ActivateDevice(devkey, 0);
    if (hDev==NULL) {
        error("ActivateDevice(%08lx - %ls)", hDev, devkey);
        return 1;
    }
    debug("dev=%08lx\n", hDev);
    return 0;
}