getline.c

/*
 * Check: a unit test framework for C
 * Copyright (C) 2001, 2002 Arien Malec
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 */

#include "libcompat.h"
#include <stdio.h>

#define INITIAL_SIZE 16
#define DELIMITER '\n'

ssize_t getline(char **lineptr, size_t *n, FILE *stream)
{
     ssize_t written = 0;
     int character;

     if(*lineptr == NULL || *n < INITIAL_SIZE)
     {
          free(*lineptr);
          *lineptr = (char *)malloc(INITIAL_SIZE);
          *n = INITIAL_SIZE;
     }

     while( (character = fgetc(stream)) != EOF)
     {
          written += 1;
          if(written >= *n)
          {
               *n = *n * 2;
               *lineptr = realloc(*lineptr, *n);
          }

          (*lineptr)[written-1] = character;

          if(character == DELIMITER)
          {
               break;
          }
     }

     (*lineptr)[written] = '\0';

     return written;
}