buffer.c

/* buffer.c
 *
 * A bare-bones string stream.
 */

/* nettle, low-level cryptographics library
 *
 * Copyright (C) 2002 Niels Mller
 *  
 * The nettle 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.
 * 
 * The nettle 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 the nettle library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA 02111-1307, USA.
 */

#if HAVE_CONFIG_H
# include "config.h"
#endif

#include <assert.h>
#include <stdlib.h>
#include <string.h>

#include "buffer.h"

int
nettle_buffer_grow(struct nettle_buffer *buffer,
		   unsigned length)
{
  assert(buffer->size <= buffer->alloc);
  
  if (buffer->size + length > buffer->alloc)
    {
      unsigned alloc;
      uint8_t *p;
      
      if (!buffer->realloc)
	return 0;
      
      alloc = buffer->alloc * 2 + length + 100;
      p = buffer->realloc(buffer->realloc_ctx, buffer->contents, alloc);
      if (!p)
	return 0;
      
      buffer->contents = p;
      buffer->alloc = alloc;
    }
  return 1;
}

void
nettle_buffer_init_realloc(struct nettle_buffer *buffer,
			   void *realloc_ctx,
			   nettle_realloc_func realloc)
{
  buffer->contents = NULL;
  buffer->alloc = 0;
  buffer->realloc = realloc;
  buffer->realloc_ctx = realloc_ctx;
  buffer->size = 0;