pem_eol.cxx

// This piece of goodness performs EOL conversions from CR or LF to CRLF.
// It basically performs the work of unix2dos and mac2dos. It is needed
// because our OpenSSL keys no longer conform to RFC 1421. I don't know
// when that happened.
//
// We don't use unix2dos and mac2dos on Travis because it means we have
// to install it using Apt or Brew. This toy program will do, instead.

#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <exception>

void ConvertEOL(const char* arg);

int main(int argc, char* argv[])
{
    try
    {
        for (int i=1; i<argc; ++i)
        {
            ConvertEOL(argv[i]);
        }
    }
    catch(const std::exception& ex)
    {
        std::cerr << ex.what() << std::endl;
        return 1;
    }

    return 0;
}

void ConvertEOL(const char* arg)
{
    std::string pem;

    // Avoid some reallocations during conversion
    const size_t pem_line_break = 64;
    const size_t res_size = (pem_line_break+2)*15;
    pem.reserve(res_size);

    // Process existing file
    {
        std::ifstream file(arg);

        int ch;
        while((ch = file.get()) != EOF)
        {
            switch (ch)
            {
                default:
                    pem += ch;
                    break;
                case '\n':
                    pem += "\r\n";
                    break;
                case '\r':
                    if (file.peek() == '\n')
                        ch = file.get(); // discard
                    pem += "\r\n";
                    break;
            }
        }
    }

    // Write new file
    {
        std::ofstream file(arg);
        file.write(pem.data(), pem.size());
    }
}