Ozzy Ozzy - 14 days ago 5
C Question

Set the correct path to a file

Im trying to compile the code below, it is a code free available and Im trying to understand it. And I was trying to test it but Im getting an issue. I got a message error "Error opening file filename.txt. Error 2".

I think that should be because the file is not located in the appropriated folder. I have the file in the desktop, do you know how to set the path to the file in c as th the desktop?

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

#define BUFSIZE 1024
#define MD5LEN 16

DWORD main()
{
DWORD dwStatus = 0;
BOOL bResult = FALSE;
HCRYPTPROV hProv = 0;
HCRYPTHASH hHash = 0;
HANDLE hFile = NULL;
BYTE rgbFile[BUFSIZE];
DWORD cbRead = 0;
BYTE rgbHash[MD5LEN];
DWORD cbHash = 0;
CHAR rgbDigits[] = "0123456789abcdef";
LPCSTR filename = "filename.txt";
// Logic to check usage goes here.

hFile = CreateFile(filename,
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_FLAG_SEQUENTIAL_SCAN,
NULL);

if (INVALID_HANDLE_VALUE == hFile)
{
dwStatus = GetLastError();
printf("Error opening file %s\nError: %d\n", filename,
dwStatus);
return dwStatus;
}

// Get handle to the crypto provider
if (!CryptAcquireContext(&hProv,
NULL,
NULL,
PROV_RSA_FULL,
CRYPT_VERIFYCONTEXT))
{
dwStatus = GetLastError();
printf("CryptAcquireContext failed: %d\n", dwStatus);
CloseHandle(hFile);
return dwStatus;
}

if (!CryptCreateHash(hProv, CALG_MD5, 0, 0, &hHash))
{
dwStatus = GetLastError();
printf("CryptAcquireContext failed: %d\n", dwStatus);
CloseHandle(hFile);
CryptReleaseContext(hProv, 0);
return dwStatus;
}

while (bResult = ReadFile(hFile, rgbFile, BUFSIZE,
&cbRead, NULL))
{
if (0 == cbRead)
{
break;
}

if (!CryptHashData(hHash, rgbFile, cbRead, 0))
{
dwStatus = GetLastError();
printf("CryptHashData failed: %d\n", dwStatus);
CryptReleaseContext(hProv, 0);
CryptDestroyHash(hHash);
CloseHandle(hFile);
return dwStatus;
}
}

if (!bResult)
{
dwStatus = GetLastError();
printf("ReadFile failed: %d\n", dwStatus);
CryptReleaseContext(hProv, 0);
CryptDestroyHash(hHash);
CloseHandle(hFile);
return dwStatus;
}

cbHash = MD5LEN;
if (CryptGetHashParam(hHash, HP_HASHVAL, rgbHash, &cbHash, 0))
{
DWORD i;
printf("MD5 hash of file %s is: ", filename);
for (i = 0; i < cbHash; i++)
{
printf("%c%c", rgbDigits[rgbHash[i] >> 4],
rgbDigits[rgbHash[i] & 0xf]);
}
printf("\n");
}
else
{
dwStatus = GetLastError();
printf("CryptGetHashParam failed: %d\n", dwStatus);
}

CryptDestroyHash(hHash);
CryptReleaseContext(hProv, 0);
CloseHandle(hFile);

return dwStatus;
}

Answer

Or copy the file to where .exe resides.