Evening everyone I wondered if some could answer me 2 quick questions.
I made an app to communicate with arm device which works fine, however when I move PC etc, I need to reconfigure the device path. Its a long one like below.
Path: \\?\usb#vid_045e&pid_0040#6&ff454f2&0&3#{a5dcbf10-6530-11d2-901f-00c04fb951ed}
I done some reading up and discovered it's two features SetupDiGetClassDevs and SetupDiGetDeviceInstanceId I need. My question is am I looking in the right place i.e will these 2 functions return the path like above. Also what is the techinical name for this path?
I found what I think is a nice example (always learn better from example) on Microsoft's website cut and paste below but this throws up error C2440: '=' : cannot convert from 'HLOCAL' to 'LPTSTR'
which is a new one on me a pointer error?
This is the code
#include <stdio.h>
#include <windows.h>
#include <setupapi.h>
#include <devguid.h>
#include <regstr.h>
int main( int argc, char *argv[ ], char *envp[ ] )
{
HDEVINFO hDevInfo;
SP_DEVINFO_DATA DeviceInfoData;
DWORD i;
// Create a HDEVINFO with all present devices.
hDevInfo = SetupDiGetClassDevs(NULL,
0, // Enumerator
0,
DIGCF_PRESENT | DIGCF_ALLCLASSES );
if (hDevInfo == INVALID_HANDLE_VALUE)
{
// Insert error handling here.
return 1;
}
// Enumerate through all devices in Set.
DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
for (i=0;SetupDiEnumDeviceInfo(hDevInfo,i,
&DeviceInfoData);i++)
{
DWORD DataT;
LPTSTR buffer = NULL;
DWORD buffersize = 0;
//
// Call function with null to begin with,
// then use the returned buffer size (doubled)
// to Alloc the buffer. Keep calling until
// success or an unknown failure.
//
// Double the returned buffersize to correct
// for underlying legacy CM functions that
// return an incorrect buffersize value on
// DBCS/MBCS systems.
//
while (!SetupDiGetDeviceRegistryProperty(
hDevInfo,
&DeviceInfoData,
SPDRP_DEVICEDESC,
&DataT,
(PBYTE)buffer,
buffersize,
&buffersize))
{
if (GetLastError() ==
ERROR_INSUFFICIENT_BUFFER)
{
// Change the buffer size.
if (buffer) LocalFree(buffer);
// Double the size to avoid problems on
// W2k MBCS systems per KB 888609.
buffer = LocalAlloc(LPTR,buffersize * 2); // ERROR LINE
}
else
{
// Insert error handling here.
break;
}
}
printf("Result:[%s]\n",buffer);
if (buffer) LocalFree(buffer);
}
if ( GetLastError()!=NO_ERROR &&
GetLastError()!=ERROR_NO_MORE_ITEMS )
{
// Insert error handling here.
return 1;
}
// Cleanup
SetupDiDestroyDeviceInfoList(hDevInfo);
return 0;
}
Hope its an easy one thank you.
You need to typecast the return value from LocalAlloc():
buffer = (LPSTR) LocalAlloc(LPTR,buffersize * 2);
For more info, see the LocalAlloc() documentation on MSDN.
Related
i'm developing on a Bluetooth Low Energy Device and i need to see in code if the device is connected or not.
First thing i noticed was that there is in the Devicemanager a Attribute "Verbunden"-> English: Connected and it says true or false if my device is connected or not. So i need to read that Attribute in my program.
What i have tried till now:
Getting all Devices with SetupDiGetClassDevs
Getting the FriendlyName with SetupDiGetDeviceRegistryProperty
Searching for my Device with the name.
That works.
Now i wanted to get that Connected-Attribute but i didn't find out what i have to use at SetupDiGetDeviceRegistryProperty.
SetupDiGetDeviceRegistryProperty is described here https://msdn.microsoft.com/en-us/library/windows/hardware/ff551967(v=vs.85).aspx
Maybe someone knows what is the right value for Property.
My Code:
int get_device_info( void )
{
HDEVINFO hDevInfo;
SP_DEVINFO_DATA DeviceInfoData;
DWORD i;
FILE * devices = fopen("devices.txt", "a+");
GUID AGuid;
//GUID can be constructed from "{xxx....}" string using CLSID
CLSIDFromString(TEXT(TO_SEARCH_DEVICE_UUID), &AGuid);
GUID BluetoothInterfaceGUID = AGuid;
// Create a HDEVINFO with all present devices.
hDevInfo = SetupDiGetClassDevs(&BluetoothInterfaceGUID,
0, // Enumerator
0,
DIGCF_ALLCLASSES | DIGCF_PRESENT);
if (hDevInfo == INVALID_HANDLE_VALUE)
{
// Insert error handling here.
return 1;
}
// Enumerate through all devices in Set.
DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
for (i=0;SetupDiEnumDeviceInfo(hDevInfo,i,
&DeviceInfoData);i++)
{
DWORD DataT;
LPTSTR buffer = NULL;
DWORD buffersize = 0;
//
// Call function with null to begin with,
// then use the returned buffer size (doubled)
// to Alloc the buffer. Keep calling until
// success or an unknown failure.
//
// Double the returned buffersize to correct
// for underlying legacy CM functions that
// return an incorrect buffersize value on
// DBCS/MBCS systems.
//
while (!SetupDiGetDeviceRegistryProperty(
hDevInfo,
&DeviceInfoData,
SPDRP_FRIENDLYNAME,
//SPDRP_DEVICEDESC,
//SPDRP_CAPABILITIES,
&DataT,
(PBYTE)buffer,
buffersize,
&buffersize))
{
if (GetLastError() ==
ERROR_INSUFFICIENT_BUFFER)
{
// Change the buffer size.
if (buffer) LocalFree(buffer);
// Double the size to avoid problems on
// W2k MBCS systems per KB 888609.
buffer = (wchar_t *)LocalAlloc(LPTR,buffersize * 2);
}
else
{
// Insert error handling here.
break;
}
}
if(buffer)
{
if( strcmp("Name of Device",AnsiString(buffer).c_str())==0)
{
fprintf(devices,"Result:[%s]",AnsiString(buffer).c_str());
if (buffer) LocalFree(buffer);
}
}
}
if ( GetLastError()!=NO_ERROR &&
GetLastError()!=ERROR_NO_MORE_ITEMS )
{
// Insert error handling here.
return 1;
}
// Cleanup
SetupDiDestroyDeviceInfoList(hDevInfo);
fclose(devices);
return 0;
}
Instead of using SetupDiEnumDeviceInfo, you would try:
1. using SetupDiEnumDeviceInterfaces
2. using SetupDiGetDeviceInterfaceProperty
3. using SetupDiGetDeviceInterfacePropertyKeys to get a list of all Property Keys available for the interface
4. using SetupDiGetDeviceProperty and/or SetupDiGetDeviceRegistryProperty
Instead of using SPDRP_XXX constants, you would use DEVPROP, as defined in 'devpkey.h' ...
Below are a few examples taken from the log of a test prog I wrote to discover the whole thing:
DEVPROPNAME: DEVPKEY_DeviceInterface_Bluetooth_DeviceAddress
DEVPROPGUID: {2BD67D8B-8BEB-48D5-87E0-6CDA3428040A}
DEVPROPPID: 1
DEVPROPTYPE: DEVPROP_TYPE_STRING
Value: c026df001017
DEVPROPNAME: DEVPKEY_Device_Children
DEVPROPGUID: {4340A6C5-93FA-4706-972C-7B648008A5A7}
DEVPROPPID: 9
DEVPROPTYPE: DEVPROP_TYPE_STRING_LIST
Value:
BTHLEDevice\{00001800-0000-1000-8000-00805f9b34fb}_c026df001017\8&2fd07168&1&0001
BTHLEDevice\{00001801-0000-1000-8000-00805f9b34fb}_c026df001017\8&2fd07168&1&0008
BTHLEDevice\{00001809-0000-1000-8000-00805f9b34fb}_c026df001017\8&2fd07168&1&000c
BTHLEDevice\{0000180f-0000-1000-8000-00805f9b34fb}_c026df001017\8&2fd07168&1&0010
BTHLEDevice\{0000180a-0000-1000-8000-00805f9b34fb}_c026df001017\8&2fd07168&1&0014
BTHLEDevice\{00001523-1212-efde-1523-785feabcd123}_c026df001017\8&2fd07168&1&0019
On a second subject, you are 'working' on the 'device' itself ( SetupDiGetClassDevs(&BluetoothInterfaceGUID...) [and then working on the \BTHLE\ tree in Registry].
After listing all GattServices of this device and getting their uuids, you could restart that iteration on the device_guid itself SetupDiGetClassDevs(&GattServiceGUID...) [and then working on the \BTHLEDevice\ tree in Registry].
Now, to answer your question, I'm still searching myself :) But I'm not really sure:
1) that it is a working (dynamic) information to know the connection state
2) that it is a 'Property' you can access by the above methods
I have found out a solution.
GUID AGuid;
//GUID can be constructed from "{xxx....}" string using CLSID
CLSIDFromString(TEXT(TO_SEARCH_DEVICE_UUID), &AGuid);
GUID BluetoothInterfaceGUID = AGuid;
// Create a HDEVINFO with all present devices.
hDevInfo = SetupDiGetClassDevs(&BluetoothInterfaceGUID,
0, // Enumerator
0,
DIGCF_ALLCLASSES | DIGCF_PRESENT);//DIGCF_DEVICEINTERFACE | DIGCF_PRESENT);//DIGCF_ALLCLASSES | DIGCF_PRESENT);
if (hDevInfo == INVALID_HANDLE_VALUE)
{
// Insert error handling here.
return 1;
}
// Enumerate through all devices in Set.
DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
for (i=0;SetupDiEnumDeviceInfo(hDevInfo,i,
&DeviceInfoData);i++)
{
DWORD DataT;
LPTSTR buffer = NULL;
LPTSTR buffer1 = NULL;
DWORD buffersize = 0;
while (!SetupDiGetDeviceRegistryProperty( // Get Name
hDevInfo,
&DeviceInfoData,
SPDRP_FRIENDLYNAME,
&DataT,
(PBYTE)buffer,
buffersize,
&buffersize))
{
if (GetLastError() ==
ERROR_INSUFFICIENT_BUFFER)
{
// Change the buffer size.
if (buffer) LocalFree(buffer);
// Double the size to avoid problems on
// W2k MBCS systems per KB 888609.
buffer = (wchar_t *)LocalAlloc(LPTR,buffersize * 2);
}
else
{
// Insert error handling here.
break;
}
}
{
if(strcmp("Your Device",AnsiString(buffer).c_str())==0) //Found your device
{
//########
DEVPROPTYPE ulPropertyType;
DWORD dwSize;
ULONG devst;
// memset(devst,0,sizeof(devst));
bool err = SetupDiGetDeviceProperty( //Checking Connection State
hDevInfo,
&DeviceInfoData,
&DEVPKEY_Device_DevNodeStatus, //Connected(0x02000000)
&ulPropertyType,
(BYTE *) &devst,
sizeof(devst),
&dwSize,
0);
DWORD error;
error = GetLastError();
if (devst &0x02000000) {
//"Status: Getrennt "
}
else
{
//"Status: Verbunden"
}
Hope this snippet helps.
I'm trying to call DeviceIoControl(IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS) API, as shown here, but I need it to first "tell me" how much memory it needs (unlike the code I linked to.)
So I call it as such:
//First determine how much data do we need?
BYTE dummyBuff[1];
DWORD bytesReturned = 0;
if(!::DeviceIoControl(hDevice, dwIoControlCode, lpInBuffer, nInBufferSize,
dummyBuff, sizeof(dummyBuff), &bytesReturned, NULL))
{
//Check last error
int nError = ::GetLastError();
if(nOSError == ERROR_INSUFFICIENT_BUFFER ||
nOSError == ERROR_MORE_DATA)
{
//Alloc memory from 'bytesReturned' ...
}
}
but it always returns error code 87, or ERROR_INVALID_PARAMETER and my bytesReturned is always 0.
So what am I doing wrong?
The instructions for getting all disk volume extents are documented under the VOLUME_DISK_EXTENTS structure:
When the number of extents returned is greater than one (1), the error code ERROR_MORE_DATA is returned. You should call DeviceIoControl again, allocating enough buffer space based on the value of NumberOfDiskExtents after the first DeviceIoControl call.
The behavior, if you pass an output buffer, that is smaller than sizeof(VOLUME_DISK_EXTENTS) is also documented at IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS control code:
If the output buffer is less than sizeof(VOLUME_DISK_EXTENTS), the call fails, GetLastError returns ERROR_INSUFFICIENT_BUFFER, and lpBytesReturned is 0 (zero).
While this explains the returned value in lpBytesReturned, it doesn't explain the error code 87 (ERROR_INVALID_PARAMETER)1).
The following code will return the disk extents for all volumes:
VOLUME_DISK_EXTENTS vde = { 0 };
DWORD bytesReturned = 0;
if ( !::DeviceIoControl( hDevice, IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS, NULL, 0,
(void*)&vde, sizeof(vde), &bytesReturned, NULL ) )
{
// Check last error
int nError = ::GetLastError();
if ( nError != ERROR_MORE_DATA )
{
// Unexpected error -> error out
throw std::runtime_error( "DeviceIoControl() failed." );
}
size_t size = offsetof( VOLUME_DISK_EXTENTS, Extents[vde.NumberOfDiskExtents] );
std::vector<BYTE> buffer( size );
if ( !::DeviceIoControl( hDevice, IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS, NULL, 0,
(void*)buffer.data(), size, &bytesReturned, NULL ) )
{
// Unexpected error -> error out
throw std::runtime_error( "DeviceIoControl() failed." );
}
// At this point we have a fully populated VOLUME_DISK_EXTENTS structure
const VOLUME_DISK_EXTENTS& result =
*reinterpret_cast<const VOLUME_DISK_EXTENTS*>( buffer.data() );
}
else
{
// Call succeeded; vde is populated with single disk extent.
}
Additional references:
Why do some structures end with an array of size 1?
offsetof Macro
1) At a guess I would assume, that BYTE[1] begins at a memory address, that is not sufficiently aligned for the alignment requirements of VOLUME_DISK_EXTENTS.
Following #IInspectable's advice, here's what I came up with for a more general case:
BYTE* DeviceIoControl_Dynamic(HANDLE hDevice, DWORD dwIoControlCode, DWORD dwszCbInitialSuggested, LPVOID lpInBuffer, DWORD nInBufferSize, DWORD* pncbOutDataSz)
{
//Calls DeviceIoControl() API by pre-allocating buffer internally
//'dwIoControlCode' = control code, see DeviceIoControl() API
//'dwszCbInitialSuggested' = suggested initial size of the buffer in BYTEs, must be set depending on the description of 'dwIoControlCode'
//'lpInBuffer' = input buffer, see DeviceIoControl() API
//'nInBufferSize' = size of 'lpInBuffer', see DeviceIoControl() API
//'pncbOutDataSz' = if not NULL, receives the size of returned data in BYTEs
//RETURN:
// = Data obtained from DeviceIoControl() API -- must be removed with delete[]!
// = NULL if error -- check GetLastError() for info
BYTE* pData = NULL;
int nOSError = NO_ERROR;
DWORD ncbSzData = 0;
if((int)dwszCbInitialSuggested > 0)
{
//Initially go with suggested memory size
DWORD dwcbMemSz = dwszCbInitialSuggested;
//Try no more than 10 times
for(int t = 0; t < 10; t++)
{
//Reserve mem
ASSERT(!pData);
pData = new (std::nothrow) BYTE[dwcbMemSz];
if(!pData)
{
//Memory fault
nOSError = ERROR_NOT_ENOUGH_MEMORY;
break;
}
//And try calling with that size
DWORD bytesReturned = 0;
if(::DeviceIoControl(hDevice, dwIoControlCode, lpInBuffer, nInBufferSize,
pData, dwcbMemSz, &bytesReturned, NULL))
{
//Got it
ncbSzData = bytesReturned;
nOSError = NO_ERROR;
break;
}
//Check last error
nOSError = ::GetLastError();
//Knowing how badly Windows drivers are written, don't rely on the last error code!
//Alloc more memory (we'll just "wing it" on the amount)
dwcbMemSz += 1024;
//Free old mem
delete[] pData;
pData = NULL;
}
}
else
{
//Bad initial size
nOSError = ERROR_INVALID_MINALLOCSIZE;
}
if(pncbOutDataSz)
*pncbOutDataSz = ncbSzData;
::SetLastError(nOSError);
return pData;
}
and then to call it, say for IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS:
DWORD bytesReturned;
VOLUME_DISK_EXTENTS* p_vde = (VOLUME_DISK_EXTENTS*)DeviceIoControl_Dynamic(hDsk,
IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS, sizeof(VOLUME_DISK_EXTENTS), NULL, NULL, &bytesReturned);
which can be later used as such:
//Ensure that driver returned the correct data
if(p_vde &&
offsetof(VOLUME_DISK_EXTENTS, Extents[p_vde->NumberOfDiskExtents]) <= bytesReturned)
{
//All good
for(int x = 0; x < p_vde->NumberOfDiskExtents; x++)
{
DWORD diskNumber = p_vde->Extents[x].DiskNumber;
//...
}
}
//Remember to free mem when not needed!
if(p_vde)
{
delete[] (BYTE*)p_vde;
p_vde = NULL;
}
You are getting error code ERROR_INVALID_PARAMETER when you have invalid parameter, like its name says. In your case it should be bad handle because all others looks fine, if we expect that dwIoControlCode argument is IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS, lpInBuffer and nInBufferSize are ignored.
In insufficient buffer you will get another error code mentioned in above comments.
Lets check what is saying documentation:
DeviceIoControl can accept a handle to a specific device. For example, to open a handle to the logical drive A: with CreateFile, specify \.\a:. Alternatively, you can use the names \.\PhysicalDrive0, \.\PhysicalDrive1, and so on, to open handles to the physical drives on a system.
In other words, when you open handle with "C:\" instead of "\\.\c:" argument in CreateFile and use it in DeviceIoControl, the result is ERROR_INVALID_PARAMETER.
I am currently trying to write a C++ program to automate retrieving information about the partitions of a sample hard-drive image, the information in question being the number of partitions on the disk and for each partition its start sector, size and and file system type.
I'm pretty sure at this point the best way to achieve this is through MSDN functions, microsofts inbuilt commands. I am trying to use the "IOCTL_DISK_GET_DRIVE_LAYOUT_EX" function, but according to my get error call my function is incorrect. When I debug the program is appears that the bool value is also unchanged after the "IOCTL_DISK_GET_DRIVE_LAYOUT_EX" call, meaning it is not returning the bResult value.
I am using Microsoft Visual C++ Express Edition. If people could take a look at my code and tell me what they think I did wrong it would be much appreciated.
#define UNICODE 1
#define _UNICODE 1
#include <windows.h>
#include <winioctl.h>
#include <stdio.h>
#define wszDrive L"\\\\.\\PhysicalDrive6"
BOOL GetDriveParition(LPWSTR wszPath, DRIVE_LAYOUT_INFORMATION_EX *pdg)
{
HANDLE hDevice = INVALID_HANDLE_VALUE; // handle to the drive to be examined
BOOL bResult = FALSE; // results flag
DWORD junk = 0; // discard results
hDevice = CreateFileW(wszPath, // drive to open
0, // no access to the drive
FILE_SHARE_READ | // share mode
FILE_SHARE_WRITE,
NULL, // default security attributes
OPEN_EXISTING, // disposition
0, // file attributes
NULL); // do not copy file attributes
if (hDevice == INVALID_HANDLE_VALUE) // cannot open the drive
{
return (FALSE);
}
bResult = DeviceIoControl(
hDevice, // handle to device
IOCTL_DISK_GET_DRIVE_LAYOUT_EX, // dwIoControlCode
NULL, // lpInBuffer
0, // nInBufferSize
pdg, // lpOutBuffer
sizeof(*pdg), // nOutBufferSize
&junk, // lpBytesReturned
NULL); // lpOverlapped
CloseHandle(hDevice);
return (bResult);
}
int wmain(int argc, wchar_t *argv[])
{
DRIVE_LAYOUT_INFORMATION_EX pdg; // disk drive partition structure
BOOL bResult = FALSE; // generic results flag
bResult = GetDriveParition (wszDrive, &pdg);
if (bResult)
{
wprintf(L"Drive path = %ws\n", wszDrive);
wprintf(L"Partition Style = %I64d\n", pdg.PartitionStyle);
wprintf(L"Partition Count = %ld\n", pdg.PartitionCount);
system("Pause");
}
else
{
wprintf (L"GetDrivePartition failed. Error %ld.\n", GetLastError ());
system("Pause");
}
return ((int)bResult);
}
DRIVE_LAYOUT_INFORMATION_EX is a weird structure. It's defined as
struct {
DWORD PartitionStyle;
DWORD PartitionCount;
union {
DRIVE_LAYOUT_INFORMATION_MBR Mbr;
DRIVE_LAYOUT_INFORMATION_GPT Gpt;
};
PARTITION_INFORMATION_EX PartitionEntry[ 1 ];
}
but usually PartitionEntry is treated as a much larger array, with PartitionCount entries. This is similar to the C99 VLA mechanism. Since you'va allocated just sizeof(*pdg) bytes, there's no room for even a second PartitionEntry.
C++ hack:
struct ExtraEntries : DRIVE_LAYOUT_INFORMATION_EX
{
PARTITION_INFORMATION_EX PartitionEntry[ 9 ]; // Or some other reasonable value
};
Even if this post is a bit old, I found another way to get a fully populated PartitionEntry without creating a tricky struct. This is how I did it:
Inspired of an answer from this post: How-to-call-deviceiocontrol-to-retrieve-the-amount-of-memory-it-needs
DRIVE_LAYOUT_INFORMATION_EX dli;
DWORD bytesReturned = 0;
if (!DeviceIoControl(hDevice, IOCTL_DISK_GET_DRIVE_LAYOUT_EX, NULL, 0, (void*)&dli, sizeof(dli), &bytesReturned, NULL))
{
// Check last error if not ERROR_INSUFFICIENT_BUFFER then return
int nError = GetLastError();
if (nError != ERROR_INSUFFICIENT_BUFFER)
{
// std::cout << "DeviceIoControl() Failed: " << nError << std::endl;
CloseHandle(hDevice);
return false;
}
// Allocate enough buffer space based of the value of Partition Count:
size_t size = offsetof(DRIVE_LAYOUT_INFORMATION_EX, PartitionEntry[dli.PartitionCount]);
std::vector<BYTE> buffer(size);
if (!DeviceIoControl(hDevice, IOCTL_DISK_GET_DRIVE_LAYOUT_EX, NULL, 0, (void*)buffer.data(), size, &bytesReturned, NULL))
{
nError = GetLastError();
// std::cout << "DeviceIoControl() Failed: " << nError << std::endl;
CloseHandle(hDevice);
return false;
}
const DRIVE_LAYOUT_INFORMATION_EX& result = *reinterpret_cast<const DRIVE_LAYOUT_INFORMATION_EX*>(buffer.data());
// Here all parition entry are populated ...
// TO DO... Do your stuff with result
}
else
{
// Call succeeded; dli is populated with a signle partition entry
// TO DO... Do your stuff with dli
}
How is should a HLOCAL data type be converted to a LPTSTR data type? I'm trying to get a code snippet from Microsoft working, and this is the only error, of which I'm not sure how to resolve:
// Create a HDEVINFO with all present devices.
hDevInfo = SetupDiGetClassDevs(NULL,
0, // Enumerator
0,
DIGCF_PRESENT | DIGCF_ALLCLASSES );
if (hDevInfo == INVALID_HANDLE_VALUE)
{
// Insert error handling here.
return NULL;
}
// Enumerate through all devices in Set.
DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
for (i=0;SetupDiEnumDeviceInfo(hDevInfo, i, &DeviceInfoData);i++)
{
DWORD DataT;
LPTSTR buffer = NULL;
DWORD buffersize = 0;
//
// Call function with null to begin with,
// then use the returned buffer size (doubled)
// to Alloc the buffer. Keep calling until
// success or an unknown failure.
//
// Double the returned buffersize to correct
// for underlying legacy CM functions that
// return an incorrect buffersize value on
// DBCS/MBCS systems.
//
while (!SetupDiGetDeviceRegistryProperty(
hDevInfo,
&DeviceInfoData,
SPDRP_DEVICEDESC,
&DataT,
(PBYTE)buffer,
buffersize,
&buffersize))
{
if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
// Change the buffer size.
if (buffer) LocalFree(buffer);
// Double the size to avoid problems on
// W2k MBCS systems per KB 888609.
buffer = LocalAlloc(LPTR,buffersize * 2); // <- Error Occurs Here
}
else
{
// Insert error handling here.
break;
}
}
printf("Result:[%s]\n",buffer);
if (buffer) LocalFree(buffer);
}
if ( GetLastError()!=NO_ERROR && GetLastError()!=ERROR_NO_MORE_ITEMS )
{
// Insert error handling here.
return NULL;
}
// Cleanup
SetupDiDestroyDeviceInfoList(hDevInfo);
Thoughts are welcome. Thanks.
LocalLock() returns the pointer. But this is 18 year old silliness, just use
// Change the buffer size.
delete buffer;
// Double the size to avoid problems on
// W2k MBCS systems per KB 888609.
buffer = new TCHAR[buffersize * 2];
Ignoring the ~7 year old silliness of still using TCHAR for a moment. Your printf() statement needs work, depending on whether or not you are compiling with Unicode. %ls if you do. I'm guessing that's your real problem, use wprintf().
buffer = (LPTSTR)LocalAlloc(LPTR, buffersize * 2);
How to get hardware id of the usb device using device id...i am using vc++6.0 and OS is xp.
is it possible by using wmi.
Finally i solved my problem...thanks for your replies...
I am posting the code here, it may be useful for someone... by this code we can get all hardwareids of the devices which are connceted to our system..
HDEVINFO hDevInfo;
SP_DEVINFO_DATA DeviceInfoData;
DWORD i;
// Create a HDEVINFO with all present devices.
hDevInfo = SetupDiGetClassDevs(NULL,
0, // Enumerator
0,
DIGCF_PRESENT | DIGCF_ALLCLASSES );
if (hDevInfo == INVALID_HANDLE_VALUE)
{
//Error handling here.
printf("Error Details:[%s]\n","INVALID_HANDLE_VALUE");
return 1;
}
// Enumerate through all devices in Set.
DeviceInfoData.cbSize = sizeof(SP_DEVINFO_DATA);
for (i=0;SetupDiEnumDeviceInfo(hDevInfo,i,
&DeviceInfoData);i++)
{
DWORD DataT;
LPTSTR buffer = NULL;
LPTSTR hwbuffer=NULL;
DWORD buffersize = 0;
//
// Call function with null to begin with,
// then use the returned buffer size (doubled)
// to Alloc the buffer. Keep calling until
// success or an unknown failure.
//
// Double the returned buffersize to correct
// for underlying legacy CM functions that
// return an incorrect buffersize value on
// DBCS/MBCS systems.
//
while (!SetupDiGetDeviceRegistryProperty(
hDevInfo,
&DeviceInfoData,
SPDRP_HARDWAREID,
&DataT,
(PBYTE)buffer,
buffersize,
&buffersize))
{
if (GetLastError() ==
ERROR_INSUFFICIENT_BUFFER)
{
// Change the buffer size.
if (buffer) LocalFree(buffer);
// Double the size to avoid problems on
// W2k MBCS systems per KB 888609.
buffer = (char*)LocalAlloc(LPTR,buffersize * 2);
}
else
{
//Error handling here.
//printf("Error Details:[%s]\n",GetLastError());
break;
}
}
printf("Test Result:[%s]\n",buffer);
if (buffer) LocalFree(buffer);
}
if ( GetLastError()!=NO_ERROR &&
GetLastError()!=ERROR_NO_MORE_ITEMS )
{
// Error handling here.
printf("Error Details:[%s]\n",GetLastError());
return 1;
}
// Cleanup
SetupDiDestroyDeviceInfoList(hDevInfo);
return 0;
You might be somewhat confused because you assume the hardware ID. IoGetDeviceProperty(yourDevice, DevicePropertyHardwareID, ...) returns a list.