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Abinash Mohanty wrote: Can anybody tell me how to retreive hard disk interface type without using WMI classes in MFC
Hi Abinash,
The MFC classes[^] are a very small subset of the Microsoft Windows API. The answer to your question is that MFC does not have any methods of determining a drive volume bus type.
But you can use the IOCTL_STORAGE_QUERY_PROPERTY[^] control code to obtain the STORAGE_BUS_TYPE[^]. Here is an example:
#include <winioctl.h>
#define IOCTL_STORAGE_QUERY_PROPERTY CTL_CODE(IOCTL_STORAGE_BASE, 0x0500, METHOD_BUFFERED, FILE_ANY_ACCESS)
STORAGE_BUS_TYPE GetDriveBusType(DWORD dwDrive)
{
STORAGE_BUS_TYPE sbt = BusTypeUnknown;
HANDLE hDrive;
TCHAR szDrive[MAX_PATH];
_stprintf(szDrive,_T("\\\\.\\PhysicalDrive%d"), dwDrive);
hDrive = CreateFile(szDrive,GENERIC_READ | GENERIC_WRITE,FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,NULL, OPEN_EXISTING, 0, NULL);
if(INVALID_HANDLE_VALUE != hDrive)
{
DWORD dwSizeBytes;
STORAGE_PROPERTY_QUERY q;
ZeroMemory(&q,sizeof(STORAGE_PROPERTY_QUERY));
PBYTE pBuf = (PBYTE)HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,sizeof(STORAGE_DESCRIPTOR_HEADER));
if(NULL != pBuf)
{
if(TRUE == DeviceIoControl(hDrive,IOCTL_STORAGE_QUERY_PROPERTY,&q,sizeof(STORAGE_PROPERTY_QUERY),pBuf,sizeof(STORAGE_DESCRIPTOR_HEADER),&dwSizeBytes, NULL))
{
STORAGE_DESCRIPTOR_HEADER *pHeader = (STORAGE_DESCRIPTOR_HEADER *)pBuf;
dwSizeBytes = pHeader->Size;
pBuf = (PBYTE)HeapReAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,pBuf,dwSizeBytes);
if(NULL != pBuf)
{
if(TRUE == DeviceIoControl(hDrive,IOCTL_STORAGE_QUERY_PROPERTY,&q,sizeof(STORAGE_PROPERTY_QUERY),pBuf,dwSizeBytes,&dwSizeBytes, NULL))
{
STORAGE_DEVICE_DESCRIPTOR * pDesc = (STORAGE_DEVICE_DESCRIPTOR *)pBuf;
sbt = pDesc->BusType;
}
}
}
HeapFree(GetProcessHeap(), 0, (LPVOID)pBuf);
}
}
return sbt;
}
Best Wishes,
-David Delaune
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I am currently having problems with my ADO connection string. I have searched all over the internet for a solution to this problem but I have yet to find a solution. Can someone help me with the proper configuration for a SQL OLEDB connection with a windows authentication? Included is my C++ code file. I cannot include my SQL Server signon but can send a printscreen via e-mail attachment.
// ConnectionString.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
// ConnectionStringSampleCpp.cpp
// compile with: /EHsc
//#import "msado15.dll" no_namespace rename("EOF", "EndOfFile")
#import "c:\Program Files\Common Files\System\ADO\msado15.dll" no_namespace rename("EOF", "EOFile")
// Function declarations
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);};
void ConnectionStringX();
_bstr_t GetState(int intState);
void PrintProviderError(_ConnectionPtr pConnection);
void PrintComError(_com_error &e);
int main() {
if (FAILED(::CoInitialize(NULL)))
return 0;
ConnectionStringX();
::CoUninitialize();
}
void ConnectionStringX() {
// Define Connection object pointers. Initialize pointers on define. These are in the ADODB:: namespace
_ConnectionPtr pConnection1 = NULL;
_ConnectionPtr pConnection2 = NULL;
_ConnectionPtr pConnection3 = NULL;
_ConnectionPtr pConnection4 = NULL;
// Define Other Variables
HRESULT hr = S_OK;
try {
// Open a connection using OLE DB syntax.
TESTHR(pConnection1.CreateInstance(__uuidof(Connection)));
//pConnection1->ConnectionString = "Provider='sqloledb';Data Source='(local)';"
// "Initial Catalog='DSNPubs';Integrated Security='SSPI';";
//pConnection1->ConnectionString = "Provider='sqloledb';Server='PCD-LT-MCERTINI\\SQLEXPRESS';"
// "AttachDbFilename='C:\\SQL Server 2000 Sample Databases\\NORTHWND.mdf';Initial Catalog='northwind';Trusted_Connection=Yes;";
pConnection1->ConnectionString = "Provider='SQLOLEDB.1';Persist Security Info='True';User ID='mcertini';Initial Catalog='northwind';Data Source='PCD-LT-MCERTINI\\SQLEXPRESS';";
//pConnection1->ConnectionString = "Provider='SQLNCLI10';Data Source='NORTHWND.mdf';";
pConnection1->ConnectionTimeout = 30;
pConnection1->Open("", "", "",adConnectUnspecified);
printf("cnn1 state: %s\n", (LPCTSTR)GetState(pConnection1->State));
// Open a connection using a DSN and ODBC tags.
// It is assumed that you have create DSN 'DataPubs' with a user name as
// 'MyUserId' and password as 'MyPassword'.
//TESTHR(pConnection2.CreateInstance(__uuidof(Connection)));
//pConnection2->ConnectionString = "DSN=DataPubs;UID=MyUserId;PWD=MyPassword;";
//pConnection2->Open("", "", "", adConnectUnspecified);
//printf("cnn2 state: %s\n", (LPCTSTR)GetState(pConnection2->State));
// Open a connection using a DSN and OLE DB tags.
//TESTHR(pConnection3.CreateInstance(__uuidof(Connection)));
//pConnection3->ConnectionString = "Data Source=DataPubs;";
//pConnection3->Open("", "", "", adConnectUnspecified);
//printf("cnn3 state: %s\n", (LPCTSTR)GetState(pConnection3->State));
// Open a connection using a DSN and individual arguments instead of a connection string.
// It is assumed that you have create DSN 'DataPubs' with a user name as
// 'MyUserId' and password as 'MyPassword'.
//TESTHR(pConnection4.CreateInstance(__uuidof(Connection)));
//pConnection4->Open("DataPubs", "MyUserId", "MyPassword", adConnectUnspecified);
//printf("cnn4 state: %s\n", (LPCTSTR)GetState(pConnection4->State));
}
catch(_com_error &e) {
// Notify user of any errors. Pass a connection pointer accessed from the Connection.
PrintProviderError(pConnection1);
if (pConnection2)
PrintProviderError(pConnection2);
if (pConnection3)
PrintProviderError(pConnection3);
if (pConnection4)
PrintProviderError(pConnection4);
PrintComError(e);
}
// Cleanup objects before exit.
if (pConnection1)
if (pConnection1->State == adStateOpen)
pConnection1->Close();
if (pConnection2)
if (pConnection2->State == adStateOpen)
pConnection2->Close();
if (pConnection3)
if (pConnection3->State == adStateOpen)
pConnection3->Close();
if (pConnection4)
if (pConnection4->State == adStateOpen)
pConnection4->Close();
}
_bstr_t GetState(int intState) {
_bstr_t strState;
switch(intState) {
case adStateClosed:
strState = "adStateClosed";
break;
case adStateOpen:
strState = "adStateOpen";
break;
default:
;
}
return strState;
}
void PrintProviderError(_ConnectionPtr pConnection) {
// Print Provider Errors from Connection object.
// pErr is a record object in the Connection's Error collection.
ErrorPtr pErr = NULL;
if ( (pConnection->Errors->Count) > 0) {
long nCount = pConnection->Errors->Count;
// Collection ranges from 0 to nCount -1.
for ( long i = 0 ; i < nCount ; i++ ) {
pErr = pConnection->Errors->GetItem(i);
printf("Error number: %x\t%s\n", pErr->Number, (LPCSTR)pErr->Description);
}
}
}
void PrintComError(_com_error &e) {
_bstr_t bstrSource(e.Source());
_bstr_t bstrDescription(e.Description());
// Print Com errors.
printf("Error\n");
printf("\tCode = %08lx\n", e.Error());
printf("\tCode meaning = %s\n", e.ErrorMessage());
printf("\tSource = %s\n", (LPCSTR) bstrSource);
printf("\tDescription = %s\n", (LPCSTR) bstrDescription);
}
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Could you post the error/problem that you are getting/facing while trying to establish the connection?
-Rane
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The following is the error message I am receiving:
Error number: 80040e4d Login failed for user 'mcertini'.
Error
Code = 80040e4d
Code meaning = I
Source = Microsoft OLE DB Provider for SQL Server
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This error message is self-explanatory. Check whether your DSN is setup correctly. Any incorrect DSN(UserID/Pwd) will lead to this error.In addition Pl check if you have right level of access to the database.
-Rane
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Hi everybody,
I have a class called STSource ("ST" is my system prefix) and it represent a program source. i have too, more two classes called STCobol and STHtml. STSource need to execute a function that separate informations using a very specific way that have a same name inside STCobol and STHtml. I don´t like to use conditions sintaxes to check file extension and to decide which object will be instanciated (For me oCobol ou oHtml). How can i instanciated a pointer or something to this.
I need
STSource oSource
if cobol
oLanguage = STCobol
else
if HTML
oLanguage = STHtml
oLanguage.DoSomething()
and not
STSource oSource
if cobol
STCobol oCobol
else
if HTML
STHtml oHtml
if cobol
oCobol.DoSomething()
else
if HTML
oHtml.DoSomething()
Thanks for read my questions
Sorry by poor english, i´m Brazilian
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Have STCobol and STHtml be derived classes from a base class with exactly one pure virtual function named "DoSomething()". Then you can declare oLanguage as type "baseclass" and oLanguage.DoSomething() or (oLanguage->DoSomething() depending on the declaration) will invoke the proper function.
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Humm
If i understood the code will be like this
class STSource
{
public:
virtual void DoSomething()=0; //pure virtual Function Definition
};
class STCobol:public STSource
{
public:
void DoSomething()
{
cout<<"Hi...";
}
};
class STHtml:public STSource
{
public:
void DoSomething()
{
cout<<"Bye...";
}
};
class AnyClass1:
{
STSource* pArray[2];
STCobol oCobol;
STHtml oHtml;
pArray[0]=&oCobol;
pArray[1]=&oHtml;
if cobol
pAarray[0]->DoSomething();
else
if html
pArray[1]->DoSomething();
}
class AnyClass2:
{
STSource* pSource;
if cobol {
STCobol oCobol;
pSource=&oCobol;
}
else
if html {
STHtml oHtml;
pSource=&oHtml;
}
}
pLanguage->DoSomething();
One more question: When i instanciated a STCobol or STHtml, STSource wiil be instanciated automactly
are the above things correct or am i keeping crazy ?
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as i see have done it fine. 
You can do things better like:
if cobol
pAarray[0]->DoSomething();
else
if html
pArray[1]->DoSomething();
}
if the STSource has a function GetClassType() with enums. Or -> CObject and IsKindOf() 
Press F1 for help or google it.
Greetings from Germany
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For the last bit of code, I'd use something like this instead:
class AnyClass2:
{
STSource* pSource;
if cobol {
pSource=new STCobol;
}
else
if html {
pSource= new STHtml;
}
}
pSource->DoSomething();
Just remember to a) delete pSource after you're done with it, b) add a virtual destructor to STCobol and STHtml.
Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p
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Hi.
I'm using Visual Studio 2005. I want to create HTML Help from XML comment using Sandcastle Help File Builder. I'm using it for C# programs and it's working very well. But, for my C++ project, when i generated the XML file, only the classes are documented (nothing else) and all classes are described as structure.
How can i solve this problems ?
Thanks.
Noel
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I've been working on the same problem. I looked at Doxygen, but I don't like the output and really want our C++ API docs to be tightly integrated into the help web pages generated by Sandcastle for our C# API documentation.
I read somewhere that if can create a MAML file, you can do this, but I haven't been able to find out more concrete information.
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I'll take a quick look at the MAML but I'm not sure that is the true solution. I think part of the problem is when generating the xml file in Visual Studio 2005. Only the methods are included in XML files. I do not understand yet why SHFB detects classes as structures.
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Hello,
I have a more theoretical question.
If you have a class Apple
class Apple { ... }
and then you have a map of them:
std::map<int, Apple> apple_map;
Populate it with some random crap, then somewhere try and reference a value that is NOT in the map:
...
Apple& apple_ref = apple_map [key_not_in_map];
...
what is returned? can I NULL check it? My understanding is that it is the default_type for the object being referenced (Apple in this case). What is this? and how do I change/know it for developer defined classes?
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If the key is not in the map then the map creates a default constructed element. You cannot NULL check it because references are never null. If you do not define a constructor in your class then the compiler will insert a default constructor for you. To change it just define your own constructor, i.e.
Apple()
{
}
Graham
Librarians rule, Ook!
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according to this[^] :
"Returns a reference to the object that is associated with a particular key. If the map does not already contain such an object, operator[] inserts the default object data_type()"
and
"Note that the definition of operator[] is extremely simple: m[k] is equivalent to (*((m.insert(value_type(k, data_type()))).first)).second"
It will create a new Apple and insert it at that key "position"; so it will always succeed and return a valid object.
Use std::map::find instead.
This signature was proudly tested on animals.
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I will use that if I am unsure, does it run in the same time as the [] look up?
Thanks!!!!
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it runs in the same time as the insert.
This signature was proudly tested on animals.
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Hi there guys
new to code project and new to doxygen
i have some errors in doxygen that i need help with
Hi folks
i am kind of new to doxygen and i have encoutnered a few errors i would like
help with. I have managed to create a .chm file from my c++ source code. My
first problem arises with my file names. It has stripped the whole path name
and used that as the file name. I only want to single file name. I opened up
the configuration file and tried to change the STRIP_FROM_INC_PATH = to be
left blank. I know it has something to do with FULL_PATH_NAMES ,
STRIP_FROM_PATH, STRIP_FROM_INC_PATH but i have tried to change these with
no effect to my .chm file. Can anyone please help me with this. I tried to
post an image on this messageboard showing what i was talking about but it
refused so whoever replies and needs more explanation can give me there
email and i shall send the picture to them.
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I'm debugging a Microsoft Visual C++ 2003 SDI/MFC windows app I have created. My app is using a 3rd party C++ library(DLL) for CAN msg communication. When my app starts it calls a 3rd party lib API which creats a new thread for handling CAN comm msg handling. The problem right now is that after many hours of running the app crashes with unhandled exception 0x7c90120e : user breakpoint. In the debugger output window it shows:
HEAP: Free Heap block 0x3f4e60 modified at 0x3f4e88 after it was freed.
I believe the 3rd party thread is attempting to access memory that was previously deallocated. The call stack looks like this:
ntdll.dll!7c90120e()
ntdll.dll!7c96e139()
.
.
kernel32.dll!7c80b7d0()
The threads window shows:
2024 WinMain guGetRxDataFrame <- my app function
=>2140 Win32 Thread 7c90120e <- this thread my by lib code
1) I believe the app is crashing because of the 3rd party lib
thread based on the debug info I provided above. Is my
understanding correct ? Also my code is not doing new/delete
operations but the lib code is.
2) I have access to the 3rd party lib code and have been
reviewing this "steaming pile" of poorly written code.
In it they are doing set_new_handler to install a user
function that is called when new operation fails. In the user
function they are doing throw std::bad_alloc(). I have added
try/catch(... ) in my code. In a multiple thread application
if the child thread crashes or throws an exceptoin how can my
parent thread "trap" the exception ? Is this possible ? I would like to do this so I can execute one of my user function to do some cleanup before exiting the app by installing a handler with set_terminate. I know this won't fix the root cause but I need to handle these kind of errors in my app anyways.
3) Is is possible to add a user function like set_new_handler() for the delete [] operation ? The 3rd party lib code is doing a new operation when executing a class constructor. They don't even check if the new operation was successful. Then in the class destructor they are doing a delete [] operation without even checking of the memory pointer in not NULL !!! crazy code, extremely bad. For example
4) If the child thread is leaking memory is there a way I can call function periodically to dump info to the debug window to see if memory is being chewed up over time such as CrtDumpMemoryLeaks() ?
Will setting up a time to execute CrtDumpMemoryLeaks() provide any useful info ?
Baga::Baga()
{
m_buffer = new dgUint8[MAXGFRAME];
m_framelen = sizeof( struct gframehdr );
m_gframehdr = (struct gframehdr *) m_buffer;
}
Baga::~Baga()
{
delete[] m_buffer; <- shouldn't they be check that
m_buffer is not NULL before attempting
this operation ????
}
I wish I could compile/link in the 3rd party lib code but I cannot.
This is my first debug of a multi-thread app. Need help in trying to figure out the root cause of this issue. Any other things I can try to help diagnose this problem ? Sorry, complex problem, so long email 
These problems suck but I have already learned so much from this forum and the web in trying to attack this problem.
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CodeMacDaddy wrote: I believe the app is crashing because of the 3rd party lib
thread
It seems that way, if you are certain that you've surrounded your calls to the DLL with try/catch(...) blocks and you are not doing any new/delete stuff.
This seems to be your main problem if I understand your description correctly and unfortunately it also seems like you cannot do anything about it if you're not able to build the DLL.
CodeMacDaddy wrote: I have access to the 3rd party lib code and have been
reviewing this "steaming pile" of poorly written code.
I can understand that you get frustrated during this tedious work trying to understand how it works, how it is suppose to work and why it doesn't.
However, it may not be as "poorly written" as you may think.
E.g. it's pointless to check if a memory allocation using new was successful in an exception-enabled application since if it fails it will throw an exception. Furthermore it's perfectly legal to call delete with a NULL pointer.
CodeMacDaddy wrote: In a multiple thread application
if the child thread crashes or throws an exceptoin how can my
parent thread "trap" the exception ? Is this possible ?
No, as far as I know it's not possible since exceptions are thrown within their context. So you won't be able to catch an exception thrown in a thread that is created inside your third-party DLL.
As for the root cause of your problem I can only guess, but I would bet some money on a race condition. 
It's quite possible that the worker thread inside the DLL reads incoming messages and puts them in a buffer (m_buffer?). For some reason the connection should be closed down, the Baga object destroyed and the receiving thread should be terminated. If the shutdown sequence doesn't wait for the worker thread to finish, the buffer may be freed before the thread exits. The thread may then try to write to the buffer which has already been freed in the call chain of the shutdown sequence.
Be aware that I'm only guessing, but the above is a common mistake.
When your application comes to this halt, try and find something in the call stack for each thread that makes sense instead of simple addresses. It may help you to figure out what has been executed and what the root cause of your problem is.
"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown
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Hi Roger, thank you for your insight
1) As for you guess as to what is going on that is what I am
suspecting also but since I cannot access the thread info, I
cannot provide more debug info to the 3rd party lib provided.
I've made a stripped down project which I'm sending to the 3rd
party
2) Unfortunately, the call stack is not providing any "really"
useful info
3) I agree with your point "it's pointless to check if a memory allocation using new was successful in an exception-enabled application since if it fails it will throw an exception". My issue is that the exception-enabled is being down for the worker thread only. My app is using classes and APIs provided in the lib that don't do this. So I have to do try/catch around new class objects of the lib and/or install set_new_handler in my app also
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CodeMacDaddy wrote: 2) Unfortunately, the call stack is not providing any "really"
useful info
Well, that should be fairly easy to fix; the library must have been debug built, otherwise you would not get the assertion about the heap. Debug built usually also means that you get a program database file (.pdb) as well which is used when populating the call stack with proper function names and such. You need to make sure that VS can find it such as putting it in the directory you're running your application in. But it might be that you haven't got the pdb-file delivered from the third party.
However, I find it a little bit odd that the DLL is debug built...
As I understand it, in order to fix your problem you have to be able to build the DLL. If you already have the source code for it, that shouldn't be too hard.
One way could be to create a new DLL project in VS and exchange the files created by the wizard with the files you got from the third party.
It may not work as my recommendation is based on a couple of assumptions, but it's a possible way forward that probably should be considered.
"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown
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Yes, the 3rd party lib provider only provides .dll and .lib file no .pdb file unfortunately. And yes there is a debug and release version of the .dll / .lib file when linked into my code. I have the source of the lib code to be able to built for an embedded linux platform and put the .lib file on the linux platform so I can run my app. I don't have the Microsoft project / makefile to build the DLL for the PC side otherwise I would be able to do this and further debug their source  My project has been send the 3rd party hommies, so they can help debug this issue.
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if you have the 3rd party code fix it!!! And done. 
So you can work on with your project...
Press F1 for help or google it.
Greetings from Germany
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