newlib-cygwin/newlib/libc/stdlib/__atexit.c

100 lines
2.0 KiB
C
Raw Normal View History

/*
* Common routine to implement atexit-like functionality.
*/
#include <stddef.h>
#include <stdlib.h>
#include <reent.h>
#include <sys/lock.h>
#include "atexit.h"
/* Make this a weak reference to avoid pulling in malloc. */
void * malloc(size_t) _ATTRIBUTE((__weak__));
__LOCK_INIT_RECURSIVE(, __atexit_lock);
/*
* Register a function to be performed at exit or on shared library unload.
*/
int
_DEFUN (__register_exitproc,
(type, fn, arg, d),
int type _AND
void (*fn) (void) _AND
void *arg _AND
void *d)
{
struct _on_exit_args * args;
register struct _atexit *p;
#ifndef __SINGLE_THREAD__
__lock_acquire_recursive(__atexit_lock);
#endif
p = _GLOBAL_REENT->_atexit;
if (p == NULL)
_GLOBAL_REENT->_atexit = p = &_GLOBAL_REENT->_atexit0;
if (p->_ind >= _ATEXIT_SIZE)
{
#ifndef _ATEXIT_DYNAMIC_ALLOC
return -1;
#else
/* Don't dynamically allocate the atexit array if malloc is not
available. */
if (!malloc)
return -1;
p = (struct _atexit *) malloc (sizeof *p);
if (p == NULL)
{
#ifndef __SINGLE_THREAD__
__lock_release_recursive(__atexit_lock);
#endif
return -1;
}
p->_ind = 0;
p->_next = _GLOBAL_REENT->_atexit;
_GLOBAL_REENT->_atexit = p;
#ifndef _REENT_SMALL
p->_on_exit_args._fntypes = 0;
p->_on_exit_args._is_cxa = 0;
#endif
#endif
}
if (type != __et_atexit)
{
#ifdef _REENT_SMALL
args = p->_on_exit_args_ptr;
if (args == NULL)
{
if (malloc)
args = malloc (sizeof * p->_on_exit_args_ptr);
if (args == NULL)
{
#ifndef __SINGLE_THREAD__
__lock_release(lock);
#endif
return -1;
}
args->_fntypes = 0;
args->_is_cxa = 0;
p->_on_exit_args_ptr = args;
}
#else
args = &p->_on_exit_args;
#endif
args->_fnargs[p->_ind] = arg;
args->_fntypes |= (1 << p->_ind);
args->_dso_handle[p->_ind] = d;
if (type == __et_cxa)
args->_is_cxa |= (1 << p->_ind);
}
p->_fns[p->_ind++] = fn;
#ifndef __SINGLE_THREAD__
__lock_release_recursive(__atexit_lock);
#endif
return 0;
}