newlib/winsup/cygwin/malloc_wrapper.cc

238 lines
4.6 KiB
C++

/* malloc.cc for WIN32.
Copyright 1996, 1997, 1998 Cygnus Solutions.
Written by Steve Chamberlain of Cygnus Support
sac@cygnus.com
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <stdlib.h>
/* we provide these stubs to call into a user's
provided malloc if there is one - otherwise
functions we provide - like strdup will cause
problems if malloced on our heap and free'd on theirs.
*/
static int export_malloc_called = 0;
static int use_internal_malloc = 1;
#undef in
#undef out
#define in(x)
#define out(x)
#ifdef MALLOC_DEBUG
extern "C" void * _sbrk (size_t incr_arg);
#if 0
extern "C" void *
_sbrk_r (struct _reent *, size_t incr_arg)
{
return _sbrk (incr_arg);
}
#endif
extern "C" void *
_malloc_r (struct _reent *, size_t size)
{
export_malloc_called = 1;
return malloc (size);
}
#undef malloc
extern "C" void *
_calloc_r (struct _reent *, size_t nmemb, size_t size)
{
export_malloc_called = 1;
return calloc (nmemb, size);
}
#undef calloc
extern "C" void
_free_r (struct _reent *, void *p)
{
export_malloc_called = 1;
free (p);
}
#undef free
extern "C" void *
_realloc_r (struct _reent *, void *p, size_t size)
{
export_malloc_called = 1;
return realloc (p, size);
}
#undef realloc
extern "C" char *
strdup_dbg (const char *s, const char *file, int line)
{
char *p;
export_malloc_called = 1;
if ((p = (char *) malloc_dbg (strlen (s) + 1, file, line)) != NULL)
strcpy (p, s);
return p;
}
#undef strdup
extern "C" char *
strdup (const char *s)
{
return strdup_dbg (s, __FILE__, __LINE__);
}
#else
/* Call though the application pointer,
which either points to export_malloc, or the application's
own version. */
void *
malloc (size_t size)
{
void *res;
res = user_data->malloc (size);
return res;
}
void
free (void *p)
{
user_data->free (p);
}
void *
realloc (void *p, size_t size)
{
void *res;
res = user_data->realloc (p, size);
return res;
}
void *
calloc (size_t nmemb, size_t size)
{
void *res;
res = user_data->calloc (nmemb, size);
return res;
}
#endif
/* These routines are used by the application if it
doesn't provide its own malloc. */
extern "C"
void
export_free (void *p)
{
malloc_printf ("(%p), called by %x", p, ((int *)&p)[-1]);
if (use_internal_malloc)
_free_r (_impure_ptr, p);
else
user_data->free (p);
}
extern "C"
void *
export_malloc (int size)
{
void *res;
export_malloc_called = 1;
if (use_internal_malloc)
res = _malloc_r (_impure_ptr, size);
else
res = user_data->malloc (size);
malloc_printf ("(%d) = %x, called by %x", size, res, ((int *)&size)[-1]);
return res;
}
extern "C"
void *
export_realloc (void *p, int size)
{
void *res;
if (use_internal_malloc)
res = _realloc_r (_impure_ptr, p, size);
else
res = user_data->realloc (p, size);
malloc_printf ("(%x, %d) = %x, called by %x", p, size, res, ((int *)&p)[-1]);
return res;
}
extern "C"
void *
export_calloc (size_t nmemb, size_t size)
{
void *res;
if (use_internal_malloc)
res = _calloc_r (_impure_ptr, nmemb, size);
else
res = user_data->calloc (nmemb, size);
malloc_printf ("(%d, %d) = %x, called by %x", nmemb, size, res, ((int *)&nmemb)[-1]);
return res;
}
extern "C" char *
strdup (const char *s)
{
char *p;
size_t len = strlen (s) + 1;
if ((p = (char *) malloc (len)) != NULL)
memcpy (p, s, len);
return p;
}
extern "C" char *
_strdup_r (struct _reent *, const char *s)
{
return strdup (s);
}
/* We use a critical section to lock access to the malloc data
structures. This permits malloc to be called from different
threads. Note that it does not make malloc reentrant, and it does
not permit a signal handler to call malloc. The malloc code in
newlib will call __malloc_lock and __malloc_unlock at appropriate
times. */
static NO_COPY muto *mprotect = NULL;
void
malloc_init ()
{
mprotect = new_muto (FALSE, "mprotect");
/* Check if mallock is provided by application. If so, redirect all
calls to export_malloc/free/realloc to application provided. This may
happen if some other dll calls cygwin's malloc, but main code provides
its own malloc */
if (!user_data->forkee)
{
#ifdef MALLOC_DEBUG
_free_r (NULL, _malloc_r (NULL, 16));
#else
free (malloc (16));
#endif
if (!export_malloc_called)
use_internal_malloc = 0;
}
}
extern "C"
void
__malloc_lock (struct _reent *)
{
mprotect->acquire ();
}
extern "C"
void
__malloc_unlock (struct _reent *)
{
mprotect->release ();
}