为什么仅能安装第一个设备？（50分）

UNICODE_STRING deviceName, linkName, itos;

RtlInitUnicodeString(&itos,L\"\\\\Device\\\\VC\");
deviceName.Length = 100;
deviceName.MaximumLength = 120;
deviceName.Buffer = (PWSTR)
ExAllocatePoolWithTag(PagedPool, deviceName.MaximumLength, 1633);
RtlCopyUnicodeString(&deviceName, &itos);
status = RtlIntegerToUnicodeString(lPortInstance,10,&itos);
RtlAppendUnicodeStringToString(&deviceName, &itos);

RtlInitUnicodeString(&itos,L\"\\\\DosDevices\\\\C\");
linkName.Length = 100;
linkName.MaximumLength = 120;
linkName.Buffer = (PWSTR)
ExAllocatePoolWithTag(PagedPool, linkName.MaximumLength, 1633);
RtlCopyUnicodeString(&linkName, &itos);
RtlIntegerToUnicodeString(lPortInstance+3,10,&itos);
RtlAppendUnicodeStringToString(&linkName, &itos);

IoCreateDevice{.................}
IoCreateSymbolicLink(..............)

RtlFreeUnicodeString(&linkName);
RtlFreeUnicodeString(&deviceName);

安装第一个设备是成功的，但是安装第二个设备时，linkName,itos,deviceName内容都不对了。
怎么回事？

IoCreateDevice的第五个参数是不是FILE_AUTOGENERATED_DEVICE_NAME？

IoCreateDevice的第五个参数是不是FILE_AUTOGENERATED_DEVICE_NAME？

不是，是0，看DDK的文档所FILE_AUTOGENERATED_DEVICE_NAME是由系统指定一个名称，而不用用户指定的deviceName。

我觉得问题还是处在unicodestring上，为什么第二次调用RtlInitUnicodeString(&itos,L\"\\\\Device\\\\VC\"); itos的内容就对了呢？
还有什么地方要初始化或重新分配的我没有做？

你错了。FILE_AUTOGENERATED_DEVICE_NAME的意思是在你的\\\\Device\\\\VC 当有两个以上设备时在后面自动加上\\\\Device\\\\VC0、
\\\\Device\\\\VC1的区别。
否则就需要你自己在驱动程序中自己添加来分别它们。

你的比较麻烦，我实现过你说的需求
WCHAR DName[] = L\"\\\\Device\\\\DrvPnP0\";
WCHAR LName[] = L\"\\\\??\\\\DrvPnP0\";
int instance = 0;
do
{
DName[14] = (USHORT)(\'0\' + instance);
LName[10] = (USHORT)(\'0\' + instance);
RtlInitUnicodeString(&DvcName, DName);
status = IoCreateDevice(p_DrvObj,
sizeof(DrvPnP_Extension),
&DvcName,
FILE_DEVICE_UNKNOWN,
0,
FALSE,
&p_LowDvcObj);
instance++;
} while (!NT_SUCCESS(status) && (instance < MAX_DEVICES_NUM));

斑竹说的很好，又学了一招 :D  :P

你错了。FILE_AUTOGENERATED_DEVICE_NAME的意思是在你的\\\\Device\\\\VC 当有两个以上设备时在后面自动加上\\\\Device\\\\VC0、
\\\\Device\\\\VC1的区别。
否则就需要你自己在驱动程序中自己添加来分别它们。

IoCreateDevice{.................}对了，
但是IoCreateSymbolicLink(..............)就不对了，linkName没有变。所以安装失败了。
怎么办？

奇怪哦，应该是先IoCreateSymbolicLink(..............)然后再IoCreateDevice的哦。

你错了。FILE_AUTOGENERATED_DEVICE_NAME的意思是在你的\\\\Device\\\\VC 当有两个以上设备时在后面自动加上\\\\Device\\\\VC0、
\\\\Device\\\\VC1的区别。
否则就需要你自己在驱动程序中自己添加来分别它们。

我认为你说的不对。加上此参数时，PnP Manager重新生成一个DeviceName，系统可以保证是唯一的，但与原先的name没有关系。下面是DDK文档：Directs the I/O Manager to generate a name for the device, instead of the caller specifying a DeviceName when calling this routine. The I/O Manager ensures that the name is unique. This characteristic is typically specified by a PnP bus driver to generate a name for a physical device object (PDO) for a child device on its bus. This characteristic is new for Windows 2000 and Windows 98.

TO：beaveror 你的问题是安装第二个设备时，此时使用的名字在系统中已经存在，所以创建不成功。
你可以这样写：（这个方法比较笨，但有效）
static int devcount=0;
if(devcount==0)
{
..RtlInitUnicodeString(&DvcName, L\"\"\\\\Device\\\\Drv0\");
..RtlInitUnicodeString(&linkName, L\"\"\\\\DosDevices\\\\link0\");
}
else if(devcount==1)
{
..RtlInitUnicodeString(&DvcName, L\"\"\\\\Device\\\\Drv1\");
..RtlInitUnicodeString(&linkName, L\"\"\\\\DosDevices\\\\link1\");
}
devcount++;
...
...
  

[quote]你错了。FILE_AUTOGENERATED_DEVICE_NAME的意思是在你的\\\\Device\\\\VC 当有两个以上设备时在后面自动加上\\\\Device\\\\VC0、
\\\\Device\\\\VC1的区别。
否则就需要你自己在驱动程序中自己添加来分别它们。

我认为你说的不对。加上此参数时，PnP Manager重新生成一个DeviceName，系统可以保证是唯一的，但与原先的name没有关系。下面是DDK文档：Directs the I/O Manager to generate a name for the device, instead of the caller specifying a DeviceName when calling this routine. The I/O Manager ensures that the name is unique. This characteristic is typically specified by a PnP bus driver to generate a name for a physical device object (PDO) for a child device on its bus. This characteristic is new for Windows 2000 and Windows 98.

TO：beaveror 你的问题是安装第二个设备时，此时使用的名字在系统中已经存在，所以创建不成功。
你可以这样写：（这个方法比较笨，但有效）
static int devcount=0;
if(devcount==0)
{
..RtlInitUnicodeString(&DvcName, L\"\"\\\\Device\\\\Drv0\");
..RtlInitUnicodeString(&linkName, L\"\"\\\\DosDevices\\\\link0\");
}
else if(devcount==1)
{
..RtlInitUnicodeString(&DvcName, L\"\"\\\\Device\\\\Drv1\");
..RtlInitUnicodeString(&linkName, L\"\"\\\\DosDevices\\\\link1\");
}
devcount++;
...
...
   [/quote]

我以前就是这么做的，可是我要加100个设备，代码要写多长呀。

你的比较麻烦，我实现过你说的需求
WCHAR DName[] = L\"\\\\Device\\\\DrvPnP0\";
WCHAR LName[] = L\"\\\\??\\\\DrvPnP0\";
int instance = 0;
do
{
DName[14] = (USHORT)(\'0\' + instance);
LName[10] = (USHORT)(\'0\' + instance);
RtlInitUnicodeString(&DvcName, DName);
status = IoCreateDevice(p_DrvObj,
sizeof(DrvPnP_Extension),
&DvcName,
FILE_DEVICE_UNKNOWN,
0,
FALSE,
&p_LowDvcObj);
instance++;
} while (!NT_SUCCESS(status) && (instance < MAX_DEVICES_NUM));

好像有问题,当instance>10的时候对吗？ 我得到的结果是asiic字符，有“：”“＝”之类的东东。

那就用这个：
sprintf(aName,\"\\\\Device\\\\Scanner%d\",n);
    RtlInitAnsiString(&ansiName, aName);                      
    RtlAnsiStringToUnicodeString(&uName, &ansiName, TRUE);

[编辑 -  8/15/02 by  tigerzd]

奇怪哦，应该是先IoCreateSymbolicLink(..............)然后再IoCreateDevice的哦。

先createdevice，在是symlink吧。

[quote]奇怪哦，应该是先IoCreateSymbolicLink(..............)然后再IoCreateDevice的哦。

先createdevice，在是symlink吧。 [/quote]

握手。

[quote]你的比较麻烦，我实现过你说的需求
WCHAR DName[] = L\"\\\\Device\\\\DrvPnP0\";
WCHAR LName[] = L\"\\\\??\\\\DrvPnP0\";
int instance = 0;
do
{
DName[14] = (USHORT)(\'0\' + instance);
LName[10] = (USHORT)(\'0\' + instance);
RtlInitUnicodeString(&DvcName, DName);
status = IoCreateDevice(p_DrvObj,
sizeof(DrvPnP_Extension),
&DvcName,
FILE_DEVICE_UNKNOWN,
0,
FALSE,
&p_LowDvcObj);
instance++;
} while (!NT_SUCCESS(status) && (instance < MAX_DEVICES_NUM));

好像有问题,当instance>10的时候对吗？ 我得到的结果是asiic字符，有“：”“＝”之类的东东。 [/quote]
你把他的DName[14] = (USHORT)(\'0\' + instance);
LName[10] = (USHORT)(\'0\' + instance);
改成UNCODE的看看。就是RtlIntegerToUnicode(..instance..)。
怎么能这样做，unicode呀。

请看一看我的代码的相关部分吧！
#include <wdm.h>
#include \"Avalanch.h\"

#if defined(USING_GUIDS)
    // drivers interface GUID (valid when using GUID interface)
CONST GUID guid_class_Avalanch = { 0x0ec25560L, 0xee9f, 0x11df,{ 0x9b, 0x77, 0x20, 0x00, 0xc0, 0xd4, 0xc3, 0xbf } };
#endif

NTSTATUS
DriverEntry(
IN PDRIVER_OBJECT DriverObject,
IN PUNICODE_STRING pRegistryPath
)
{
DriverObject->DriverExtension->AddDevice = Avalanch_AddDevice;
DriverObject->DriverStartIo = Avalanch_StartIo;
DriverObject->MajorFunction[IRP_MJ_CREATE] = Avalanch_CreateDispatch;
DriverObject->MajorFunction[IRP_MJ_CLOSE] = Avalanch_CloseDispatch;
DriverObject->MajorFunction[IRP_MJ_READ] = Avalanch_Read;
DriverObject->MajorFunction[IRP_MJ_WRITE] = Avalanch_Write;
DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = Avalanch_DeviceIoControl;
DriverObject->MajorFunction[IRP_MJ_CLEANUP] = Avalanch_CleanupDispatch;
DriverObject->MajorFunction[IRP_MJ_POWER] = Avalanch_PowerDispatch;
DriverObject->MajorFunction[IRP_MJ_SYSTEM_CONTROL] = Avalanch_SystemControlDispatch;
DriverObject->MajorFunction[IRP_MJ_PNP] = Avalanch_PnpDispatch;
return STATUS_SUCCESS;
}

NTSTATUS
Avalanch_AddDevice(IN PDRIVER_OBJECT DriverObject, IN PDEVICE_OBJECT PhysicalDeviceObject)
{
NTSTATUS status;
ULONG InstanceNumber = 0;
PDEVICE_OBJECT FileDeviceObject = NULL;
PAVALANCH_DEVICE_EXTENSION DeviceExtension = NULL;

#if defined(USING_GUIDS)
status = Avalanch_CreateDevice(
  DriverObject,
  PhysicalDeviceObject,
  NULL,
  AVALANCH_DEVICE_TYPE,
  0,
  &FileDeviceObject
  );
if(NT_SUCCESS(status))
{
DeviceExtension = FileDeviceObject->DeviceExtension;
status = IoRegisterDeviceInterface(
  PhysicalDeviceObject,
  &guid_class_Avalanch,
  NULL,
          &DeviceExtension->SymbolicLinkName
if(NT_SUCCESS(status))   );
DeviceExtension->RegisterDeviceInterface = TRUE;
}
#else
for(InstanceNumber = 0; InstanceNumber < AVALANCH_MAX_SUPPORTED_DEVICE; InstanceNumber++)
{
status = Avalanch_CreateDevice(
  DriverObject,
  PhysicalDeviceObject,
  (PWSTR)AVALANCH_DEVICE_NAME_PREFIX,
  AVALANCH_DEVICE_TYPE,
  InstanceNumber,
  &FileDeviceObject
  );
if(status != STATUS_OBJECT_NAME_COLLISION)
break;
}
#endif
if(NT_SUCCESS(status))
{
FileDeviceObject->Flags &= ~DO_DEVICE_INITIALIZING;
FileDeviceObject->Flags |= DO_DIRECT_IO;
FileDeviceObject->Flags |= DO_POWER_PAGABLE;
}
return STATUS_SUCCESS;
}

NTSTATUS
Avalanch_CreateDevice(
 IN PDRIVER_OBJECT DriverObject,
 IN PDEVICE_OBJECT PhysicalDeviceObject,
 IN PWSTR DeviceNamePrefix,
 IN ULONG DeviceType,
 IN ULONG DeviceNumber,
 OUT PDEVICE_OBJECT *FileDeviceObject
 )
{
NTSTATUS status;
status = Avalanch_CreateDeviceObject(
DriverObject,
DeviceNamePrefix,
DeviceType,
DeviceNumber,
FileDeviceObject
);
return status;
}

NTSTATUS
Avalanch_CreateDeviceObject(
IN PDRIVER_OBJECT DriverObject,
IN PWSTR DeviceNamePrefix,
IN ULONG DeviceType,
IN ULONG DeviceNumber,
OUT PDEVICE_OBJECT *FileDeviceObject
)
{
UNICODE_STRING DeviceName = {0, 0, NULL};
//UNICODE_STRING DosDeviceName = {0, 0, NULL};
NTSTATUS status;
PAVALANCH_DEVICE_EXTENSION DeviceExtension = NULL;
#if defined(USING_GUIDS)
status = IoCreateDevice(
DriverObject,
sizeof(AVALANCH_DEVICE_EXTENSION),
NULL,
AVALANCH_DEVICE_TYPE,
0,
FALSE,
FileDeviceObject
);
#else
status = Avalanch_BuildUnicodeString(&DeviceName, DeviceNamePrefix, DeviceNumber);
if(NT_SUCCESS(status))
{
status = IoCreateDevice(
DriverObject,
sizeof(AVALANCH_DEVICE_EXTENSION),
&DeviceName,
AVALANCH_DEVICE_TYPE,
0,
FALSE,
FileDeviceObject
);
if(NT_SUCCESS(status))
{
DeviceExtension = (*FileDeviceObject)->DeviceExtension;
status = Avalanch_BuildUnicodeString(&DeviceExtension->SymbolicLinkName, (PWSTR)AVALANCH_DOS_DEVICE_NAME_PREFIX, DeviceNumber);
if(NT_SUCCESS(status))
{
status = IoCreateSymbolicLink(&DeviceExtension->SymbolicLinkName, &DeviceName);
if(!NT_SUCCESS(status))
{
IoDeleteDevice(*FileDeviceObject);
}
}
}
}
#endif

RtlFreeUnicodeString(&DeviceName);
return status;
}

NTSTATUS
Avalanch_BuildUnicodeString(OUT PUNICODE_STRING DeviceName, IN PWSTR DeviceNamePrefix, IN ULONG InstanceNumber)
{
WCHAR wcInstanceNumber[16];
UNICODE_STRING uniInstanceNumberString;
UNICODE_STRING uniDeviceNamePrefixString;
NTSTATUS status;

RtlInitUnicodeString(DeviceName, NULL);

RtlInitUnicodeString(&uniDeviceNamePrefixString, DeviceNamePrefix);

uniInstanceNumberString.Length = 0;
uniInstanceNumberString.MaximumLength = sizeof(wcInstanceNumber);
uniInstanceNumberString.Buffer = wcInstanceNumber;

status = RtlIntegerToUnicodeString(InstanceNumber, 10, &uniInstanceNumberString);
if(NT_SUCCESS(status))
{
DeviceName->MaximumLength = (USHORT)(uniDeviceNamePrefixString.Length
+ uniInstanceNumberString.Length
+ sizeof(UNICODE_NULL));
DeviceName->Buffer = ExAllocatePool(PagedPool, DeviceName->MaximumLength);

if(DeviceName->Buffer != NULL)
{
RtlZeroMemory( DeviceName->Buffer, DeviceName->MaximumLength );
RtlAppendUnicodeStringToString(DeviceName, &uniDeviceNamePrefixString);
RtlAppendUnicodeStringToString(DeviceName, &uniInstanceNumberString);
}
else
{
status = STATUS_INSUFFICIENT_RESOURCES;
}
}

return status;
}

[quote][quote]奇怪哦，应该是先IoCreateSymbolicLink(..............)然后再IoCreateDevice的哦。

先createdevice，在是symlink吧。 [/quote]

握手。 [/quote]

本来就是吗。。。

 :)

[quote]你的比较麻烦，我实现过你说的需求
WCHAR DName[] = L\"\\\\Device\\\\DrvPnP0\";
WCHAR LName[] = L\"\\\\??\\\\DrvPnP0\";
int instance = 0;
do
{
DName[14] = (USHORT)(\'0\' + instance);
LName[10] = (USHORT)(\'0\' + instance);
RtlInitUnicodeString(&DvcName, DName);
status = IoCreateDevice(p_DrvObj,
sizeof(DrvPnP_Extension),
&DvcName,
FILE_DEVICE_UNKNOWN,
0,
FALSE,
&p_LowDvcObj);
instance++;
} while (!NT_SUCCESS(status) && (instance < MAX_DEVICES_NUM));

好像有问题,当instance>10的时候对吗？ 我得到的结果是asiic字符，有“：”“＝”之类的东东。 [/quote]

>10没试过，我做的是8个设备。这因该好解决呀！你把14、10该成比较小得数试试，或者使用Rtlxxx类的函数都可以。

我搞定了，大于10或100的就用一个算法把它一个位一个位的弄出来加一下就可以了。

多谢各位了。