/*

* BigInt Input/Output

* (C) 1999-2007 Jack Lloyd

*

* Botan is released under the Simplified BSD License (see license.txt)

*/

#include <botan/bigint.h>

#include <istream>

#include <ostream>

namespace Botan {

/*

* Write the BigInt into a stream

*/

std::ostream& operator<<(std::ostream& stream, const BigInt& n)

   {

   size_t base = 10;

   if(stream.flags() & std::ios::hex)

      base = 16;

   if(stream.flags() & std::ios::oct)

      throw Invalid_Argument("Octal output of BigInt not supported");

   if(n == 0)

      stream.write("0", 1);

   else

      {

      if(n < 0)

         stream.write("-", 1);

      std::string enc;

      if(base == 10)

         enc = n.to_dec_string();

      else

         enc = n.to_hex_string();

      size_t skip = 0;

      while(skip < enc.size() && enc[skip] == '0')

         ++skip;

      stream.write(&enc[skip], enc.size() - skip);

      }

   if(!stream.good())

      throw Stream_IO_Error("BigInt output operator has failed");

   return stream;

   }

/*

* Read the BigInt from a stream

*/

std::istream& operator>>(std::istream& stream, BigInt& n)

   {

   std::string str;

   std::getline(stream, str);

   if(stream.bad() || (stream.fail() && !stream.eof()))

      throw Stream_IO_Error("BigInt input operator has failed");

   n = BigInt(str);

   return stream;

   }

}