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#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <iterator>
#include <algorithm>
using byte = unsigned char ;
std::vector<byte> get_bytes( const std::string& file_name )
{
std::ifstream file( file_name, std::ios::binary ) ; // open for input in binary mode
file >> std::noskipws ; // we want to read every byte, including white space
std::istream_iterator<byte> begin(file), end ;
return { begin, end } ;
}
// verify that the buffer contains the bytes in the file
bool verify_contents( const std::vector<byte>& buffer, const std::string& file_name )
{
std::ifstream file( file_name, std::ios::binary ) ; // open for input in binary mode
file >> std::noskipws ; // we want to read every byte, including white space
std::istream_iterator<byte> begin_file(file), end_file ;
#ifdef NDEBUG
\
return std::equal( std::begin(buffer), std::end(buffer), begin_file, end_file )
#else
const auto pair = std::mismatch( std::begin(buffer), std::end(buffer), begin_file, end_file ) ;
const bool matched = pair.first == std::end(buffer) && pair.second == end_file ;
if(matched) std::cout << "matched!\n" ;
else std::cout << "mismatch at byte #" << pair.first - std::begin(buffer) << '\n' ;
return matched ;
#endif // NDEBUG
}
int main()
{
const std::string file_name = __FILE__ ; // this file
auto buffer = get_bytes(file_name) ;
verify_contents( buffer, file_name ) ; // matched
if( buffer.size() > 123 ) ++buffer[123] ;
verify_contents( buffer, file_name ) ; // mismatch at byte #123
}
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