How to map larger bytes from raw memory into 4 bytes variable in VC++

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I have a problem in converting the values(huge) to 4 bytes values.,

//Alloc memory
UINT8 * Rawmem = (UINT8*) new[4096];

for eg.,
Below, the following, typedef unsigned int UINT32(4 bytes) and typedef unsigned char UINT8(1 byte)

from standard documentation:
assume some variable
1. System ID has 1:0 bytes 1 bytes to be allocated from total of 4096 bytes
2. FirmwareRev has 24:1 bytes are allocated from total 4096 bytes,

// On successfull allocation
I use the following construct in VC++ to map the raw bytes to a variable.,

UINT32 SysID = Rawmem[0] ;

UINT32 FrmRev = Rawmem[1] << 32 | Rawmem[2] << 24 | Rawmem[3] << 16 | Rawmem[4] <<8 | Rawmem[5];

but, in the above I am allocating 5 bytes into 4 bytes memory, what if I need to map as large as 23 bytes memory into UINT32(4bytes)? how can one accomplish the same mapping larger bytes into UINT32?

I am using VS IDE 2008,win 7 o/s.,
Misc., info: Intel proc., little endian format

Thanks in Advance.,

With Regards,
Vishalk_91

Posted 20-Jun-12 2:57am

VishalK_91

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[no name] 20-Jun-12 9:22am

UINT32 FrmRev = Rawmem[1] << 32 | Rawmem[2] << 24 | Rawmem[3] << 16 | Rawmem[4] <<8 | Rawmem[5];

This line does NOT "map" 5 bytes into 4 whatever that means. The question makes no sense.

Vitaly Tomilov 20-Jun-12 13:16pm

The question needs to be reported, it doesn't makes sense in its current form.

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Eugen Podsypalnikov · Answer 1 · 2012-06-20T04:25:00

Solution 2

// How to map larger bytes from raw memory into 4 bytes variable ?

Just set a DWORD* at a BYTE*
and then use the pointed DWORD :)

Posted 20-Jun-12 4:25am

Eugen Podsypalnikov

enhzflep · Answer 2 · 2012-06-20T03:13:00

Well, for starters that just doesn't make an iota of sense.

For seconds, your code's not doing what your claim or think it is!
Consider the following code & it's output:

C++

#include <windows.h>
#include <stdio.h>

BYTE Rawmem[5] = {0x11, 0x22, 0x33, 0x44, 0x55};
UINT32 unsignedLong32;

int main()
{
    unsignedLong32 = Rawmem[0] << 32 | Rawmem[1] << 24 | Rawmem[2] << 16 | Rawmem[3] <<8 | Rawmem[4];
    printf("0x%X\n", unsignedLong32);
}

Output:

0x22334455

What are you actually trying to do? What's the problem you're trying to solve?
There's undoubtedly a way to do it - but this certainly isn't it!