我正在尝试从特定物理扇区向SD卡写入一些数据。我从公司收到了一个代码,他们说它在windows-xp上工作正常。这与WriteFile error #5 "denied access" under win Vista/seven的情况相同 这是将数据写入SD卡的部分(在我的cae drv值中是' F')。从其他人那里读到,我添加了锁定和dismont但锁定失败(并且也卸下了)。我对Windows编程并不熟悉。任何人都可以告诉我这段代码有什么问题吗?谢谢你的帮助。 (BTW I;锁定3GiB)
u32 HDD_write(u8 drv, u32 SecAddr, u32 blocks, u8 *buf)
{
u32 ret = 0;
u32 ldistanceLow, ldistanceHigh, dwpointer, bytestoread, numread;
char cur_drv[100];
HANDLE g_hDevice;
sprintf(cur_drv, "\\\\.\\%c:",drv); // , (u32)drv);
g_hDevice = CreateFile(cur_drv, GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
if(g_hDevice == INVALID_HANDLE_VALUE)
return 0;
// lock and dismount
ret = LockFile(g_hDevice, 0, 0, 3 * 1023 * 1023 * 1023, 0);
printf("ret = %d", ret);
DeviceIoControl(g_hDevice, FSCTL_DISMOUNT_VOLUME, NULL, 0, NULL, 0, NULL, NULL);
printf("error = %d", GetLastError());
ldistanceLow = SecAddr << 9;
ldistanceHigh = SecAddr >> (32-9);
dwpointer = SetFilePointer(g_hDevice, ldistanceLow, (long *)&ldistanceHigh, FILE_BEGIN);
if(dwpointer != 0xFFFFFFFF) {
bytestoread = blocks * 512;
ret = WriteFile(g_hDevice, buf, bytestoread, (unsigned long *)&numread, NULL);
if(ret) ret = 1;
else {
ret = 0;
printf("error = %d", GetLastError());
}
}
CloseHandle(g_hDevice);
return ret;
}
答案 0 :(得分:1)
我几天前解决了这个问题,忘了在这里查看我的问题。 这是我使用的代码。在创建文件时(对于分区磁盘),我们还需要GENERIC_READ用于块设备。并且钥匙先卸下然后锁上。
u32 HDD_write(u8 drv, u32 SecAddr, u32 blocks, u8 *buf) {
u32 ret = 0;
u32 ldistanceLow, ldistanceHigh, dwpointer, bytestoread, numread;
char cur_drv[100];
HANDLE g_hDevice;
DWORD status;
//sprintf(cur_drv, "\\\\.\\PhysicalDrive%d", drv);
sprintf(cur_drv, "\\\\.\\%c:",drv);
g_hDevice = CreateFile(cur_drv, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
if(g_hDevice == INVALID_HANDLE_VALUE)
return 0;
// dismout and lock added by ckim
if (!DeviceIoControl(g_hDevice, FSCTL_DISMOUNT_VOLUME,
NULL, 0, NULL, 0, &status, NULL))
{
DWORD err = GetLastError();
printf("Error %d attempting to dismount volume, error code\n",err);
}
// lock volume
if (!DeviceIoControl(g_hDevice, FSCTL_LOCK_VOLUME,
NULL, 0, NULL, 0, &status, NULL))
{
printf("Error %d attempting to lock device\n", GetLastError());
}
ldistanceLow = SecAddr << 9;
ldistanceHigh = SecAddr >> (32-9);
dwpointer = SetFilePointer(g_hDevice, ldistanceLow, (long *)&ldistanceHigh, FILE_BEGIN);
if(dwpointer != 0xFFFFFFFF) {
bytestoread = blocks * 512;
ret = WriteFile(g_hDevice, buf, bytestoread, (unsigned long *)&numread, NULL);
if(ret) ret = 1;
else {
ret = 0;
printf("error = %d", GetLastError());
}
}
CloseHandle(g_hDevice);
return ret;
}