/*
  Copyright 2009 Nathan Phillip Brink

  This file is a part of DistRen.

  DistRen is free software: you can redistribute it and/or modify
  it under the terms of the GNU Affero General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  DistRen is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Affero General Public License for more details.

  You should have received a copy of the GNU Affero General Public License
  along with DistRen.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>

int _distren_asprintf(char **strp, const char *fmt, ...)
{
  va_list ap;
  size_t needed;

  va_start(ap, fmt);
  /**
     The return value is the size of the string that snprintf wants
     to write excluding the terminating '\0'
   */
  needed = vsnprintf(NULL, 0, fmt, ap); /*< returns the number of bytes to allocate */
  va_end(ap);
  
  needed ++;
  *strp = malloc(needed);
  if(!*strp)
    return -1;

  va_start(ap, fmt);
  /**
     The n argument must specify the size of the allocated space 
  */
  needed = vsnprintf(*strp, needed, fmt, ap);
  va_end(ap);

  return needed;
}