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From: Jack on 16 Dec 2009 05:37
Thanks Jochen once again as you come back to this
Frustrated because when I added the line
delete binfile; it just crashed with heap corruption
When I cancelled it,
There were 4 bytes of memory leak chunks repeatedly.
Thanks
Jack


From: Giovanni Dicanio on 16 Dec 2009 06:09
"Jack" <jl(a)knight.com> ha scritto nel messaggio
news:uSWo3SjfKHA.1648(a)TK2MSFTNGP05.phx.gbl...

> PBYTE binfile = new BYTE[size.QuadPart+0x1e0-4];
>
> //
> delete binfile;
> binfile = NULL;
>
> These statements are located in the same method.
> What would be the probable causes of heap corruption
> (written past the end of the heap buffer, buffer overrun i guess)

You should do (note [ and ] )

delete [] binfile;

Giovanni




From: Giovanni Dicanio on 16 Dec 2009 06:13
"Jack" <jl(a)knight.com> ha scritto nel messaggio
news:urifhWjfKHA.4112(a)TK2MSFTNGP06.phx.gbl...

> One might ask why I used new BYTE[...];
> instead of std::vector<BYTE>
>
> because I want to advance the pointer at my own will
> such as this
> binfile += 0x1e0;

If you use std::vector, you can use a raw C pointer to point inside vector,
e.g.:

std::vector< BYTE > v( << some size >> );

BYTE * binfile = &v[0];

The benefit of using vector instead of new[] is that your code is now
exception safe (e.g. if an exception is thrown, the vector releases the heap
allocated bytes).

HTH,
Giovanni


From: Jack on 16 Dec 2009 06:17
Hi Giovanni,
> std::vector< BYTE > v( << some size >> );
>
> BYTE * binfile = &v[0];
>

Sounds like that is what I am after.
Thanks Giovanni
Jack



From: Jack on 16 Dec 2009 06:44
No, still crashed

GetFileSizeEx(h, &size);

std::vector< BYTE > v( size.QuadPart+0x1e0-4 );

BYTE * binfile = &v[0];


memset (binfile, 0, size.QuadPart+0x1e4-4);
memcpy (binfile, template_bin, 0x1e0);
binfile += 0x1e0;

hFileMapping = CreateFileMapping (h, NULL, PAGE_READONLY, 0, 0, NULL);
if (hFileMapping == 0)
{
CloseHandle(h);
MessageBoxA(NULL, "Couldn't open file mapping", "Error", MB_OK);

return E_FAIL;
}

//// Get a whole file into memory
PBYTE g_pMappedFileBase = (PBYTE) MapViewOfFile (hFileMapping,
FILE_MAP_READ, 0, 0, 0);
if (g_pMappedFileBase == 0)
{
CloseHandle (hFileMapping);
CloseHandle (h);
return E_FAIL;
}

if (memcmp(g_pMappedFileBase, "hdr1", 4) == 1)
{
CloseHandle(hFileMapping);
CloseHandle(h);
MessageBoxA(NULL, "Error Loading Header", "Error", MB_OK);
return E_FAIL;
}

memcpy (binfile, g_pMappedFileBase+4, size.QuadPart-4);
binfile -= 0x1e0; // back to origin

// mucking around with it :)

Thanks
Jack



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