tinyproxy/src/heap.c

/* tinyproxy - A fast light-weight HTTP proxy
 * Copyright (C) 2002 Robert James Kaes <rjkaes@users.sourceforge.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

/* Debugging versions of various heap related functions are combined
 * here.  The debugging versions include assertions and also print
 * (to standard error) the function called along with the amount
 * of memory allocated, and where the memory is pointing.  The
 * format of the log message is standardized.
 */

#include "main.h"
#include "heap.h"
#include "text.h"

void *
debugging_calloc (size_t nmemb, size_t size, const char *file,
                  unsigned long line)
{
  void *ptr;

  assert (nmemb > 0);
  assert (size > 0);

  ptr = calloc (nmemb, size);
  fprintf (stderr, "{calloc: %p:%zu x %zu} %s:%lu\n", ptr, nmemb, size, file,
           line);
  return ptr;
}

void *
debugging_malloc (size_t size, const char *file, unsigned long line)
{
  void *ptr;

  assert (size > 0);

  ptr = malloc (size);
  fprintf (stderr, "{malloc: %p:%zu} %s:%lu\n", ptr, size, file, line);
  return ptr;
}

void *
debugging_realloc (void *ptr, size_t size, const char *file,
                   unsigned long line)
{
  void *newptr;

  assert (size > 0);

  newptr = realloc (ptr, size);
  fprintf (stderr, "{realloc: %p -> %p:%zu} %s:%lu\n", ptr, newptr, size,
           file, line);
  return newptr;
}

void
debugging_free (void *ptr, const char *file, unsigned long line)
{
  fprintf (stderr, "{free: %p} %s:%lu\n", ptr, file, line);

  if (ptr != NULL)
    free (ptr);
  return;
}

char *
debugging_strdup (const char *s, const char *file, unsigned long line)
{
  char *ptr;
  size_t len;

  assert (s != NULL);

  len = strlen (s) + 1;
  ptr = (char *)malloc (len);
  if (!ptr)
    return NULL;
  memcpy (ptr, s, len);

  fprintf (stderr, "{strdup: %p:%zu} %s:%lu\n", ptr, len, file, line);
  return ptr;
}

/*
 * Allocate a block of memory in the "shared" memory region.
 *
 * FIXME: This uses the most basic (and slowest) means of creating a
 * shared memory location.  It requires the use of a temporary file.  We might
 * want to look into something like MM (Shared Memory Library) for a better
 * solution.
 */
void *
malloc_shared_memory (size_t size)
{
  int fd;
  void *ptr;
  char buffer[32];

  static const char *shared_file = "/tmp/tinyproxy.shared.XXXXXX";

  assert (size > 0);

  strlcpy (buffer, shared_file, sizeof (buffer));

  /* Only allow u+rw bits. This may be required for some versions
   * of glibc so that mkstemp() doesn't make us vulnerable.
   */
  umask (0177);

  if ((fd = mkstemp (buffer)) == -1)
    return MAP_FAILED;
  unlink (buffer);

  if (ftruncate (fd, size) == -1)
    return MAP_FAILED;
  ptr = mmap (NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);

  return ptr;
}

/*
 * Allocate a block of memory from the "shared" region an initialize it to
 * zero.
 */
void *
calloc_shared_memory (size_t nmemb, size_t size)
{
  void *ptr;
  long length;

  assert (nmemb > 0);
  assert (size > 0);

  length = nmemb * size;

  ptr = malloc_shared_memory (length);
  if (ptr == MAP_FAILED)
    return ptr;

  memset (ptr, 0, length);

  return ptr;
}