LockResource might be causing problem

[Ali Imran]

Hi guys I have a function that extracts resources from application, it goes fine with custom resources, but when it comes to standard resources it extracts files of same size but garbage content in them.

In my applciation I have embedded two resources of type 'BITMAP', in resource file I defined them as:

117 BITMAP DISCARDABLE "p2/ide_icons/splash.bmp"
118 BITMAP DISCARDABLE "p2/ide_icons/splash.gif"

117 and 118 are resource Ids, and BITMAP is type of resource.
Now if the resource type is something else e.g. 'MYRES' defined in resource file as

117 MYRES DISCARDABLE "p2/ide_icons/splash.bmp"

it is extracted fine.

But as you can see it is is of type BITMAP, so I pass RT_BITMAP to function FindResource.


Problem is all of folowing functions pass fine
FindResource
LoadResource
LockResource

but resulting extracted data is not actual file that was in the resources, although the size is same but contents are wrong.


Please review following function and let me know what can be possible problem.

bool ExtractResource(DWORD resID, LPCSTR resType,String file)  { 
	HRSRC hResInfo = FindResource(GetModuleHandle(NULL), MAKEINTRESOURCE(resID), resType);
    if (hResInfo == NULL) return false;
	HGLOBAL hResource = LoadResource(GetModuleHandle(NULL), hResInfo);
    if (hResource == NULL) return false;      
    char *pResData = (char*)LockResource(hResource);
    DWORD resSize = SizeofResource(NULL, hResInfo);
   
    if(resSize==0) return false;

    FILE *f = fopen(file.c_str(),"w");
    fwrite(pResData,1,resSize,f);
    fclose(f);
    
    UnlockResource(hResource);
}

Will be waiting for kind reply.

regards

[kkez]

Use "MYRES" (a string, literally) instead of RT_BITMAP. IMHO RT_BITMAP is just a #define for "BITMAP".

[Ali Imran]

Sorry your answer is not satisfactory . As I already have stated that these bitmaps included in resources MUST be defined as "BITMAP" nothing else. And I also have stated that above code works with any custom resource type I define. So using "MYRES" is out of requirement. The need is loading the resource from its standard type. Oh I already know that RT_BITMAP is a define and is "BITMAP" that we define in resources file while compiling resources.

Requirement is:
1. Define as "BITMAP" in resources
117 BITMAP DISCARDABLE "p2/ide_icons/splash.bmp"

2. Load and extract by using same type "BITMAP".
Which is not working.

Any answer why does above function fail? where it is fine enough to exract from resources and all functions report properly. But resulting data that is obtained using LockResource is invalid and written to file is not the one in resources.

regards

[TheCPUWizard]

Are you 100% certain that the problem is in the extraction, and not in your file write?????

[Ali Imran]

Somehow, becuase

FILE *f = fopen(file.c_str(),"w");
fwrite(pResData,1,resSize,f);
fclose(f);

is streight C io code, I think it must work, what you say about it?

I also tried winapi specific filing method, but that writes something incorrect in output file:

    HANDLE hFile = CreateFile(file.c_str(),GENERIC_WRITE,0,NULL,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
    DWORD dwByteWritten;
    WriteFile(hFile, pResData , resSize , &dwByteWritten , NULL);
    if(dwByteWritten != resSize) return false;
    CloseHandle(hFile);

waiting for kind reply.
regards

[Ali Imran]

Guys you just posted questions and suggestions but I see no solution in your posts.
Correct the code if there is any bug, atleast I do nto see any.

Will be waiting for kind response.