A17-1-1.cpp

// Rule: A17-1-1
// Source line: 28027
// Original file: A17-1-1.cpp

// $Id: A17-1-1.cpp 289436 2017-10-04 10:45:23Z michal.szczepankiewicz $
#include <cerrno>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <stdexcept>


void Fn1(const char* filename)


{
FILE* handle = fopen(filename, "rb");
if (handle == NULL)
{
throw std::system_error(errno, std::system_category());
}
// ...
fclose(handle);


// Compliant - C code is isolated; fn1()
// function is a wrapper.

}


void Fn2() noexcept
{
try
{
Fn1("filename.txt");


// Compliant - fn1() allows you to use C code like
// C++ code


// ...



}
catch (std::system_error& e)
{
std::cerr << "Error: " << e.code() << " - " << e.what() << ’\n’;
}


}


std::int32_t Fn3(const char* filename) noexcept // Non-compliant - placing C
// functions calls along with C++
// code forces a developer to be
// responsible for C-specific error
// handling, explicit resource
// cleanup, etc.
{
FILE* handle = fopen(filename, "rb");
if (handle == NULL)
{
std::cerr << "An error occured: " << errno << " - " << strerror(errno)
<< ’\n’;
return errno;
}


try
{


// ...
fclose(handle);


}
catch (std::system_error& e)
{
fclose(handle);
}
catch (std::exception& e)
{
fclose(handle);
}


return errno;


}