[apple/libc.git] / stdlib / FreeBSD / atexit.c

/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Chris Torek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)atexit.c	8.2 (Berkeley) 7/3/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libc/stdlib/atexit.c,v 1.8 2007/01/09 00:28:09 imp Exp $");

#include "namespace.h"
#include <stddef.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#if defined(__DYNAMIC__) || defined (__BLOCKS__)
#include <dlfcn.h>
#endif /* defined(__DYNAMIC__) */
#include "atexit.h"
#include "un-namespace.h"

#ifdef __BLOCKS__
#include <Block.h>
#endif /* __BLOCKS__ */
#include "libc_private.h"

#define	ATEXIT_FN_EMPTY	0
#define	ATEXIT_FN_STD	1
#define	ATEXIT_FN_CXA	2
#ifdef __BLOCKS__
#define	ATEXIT_FN_BLK	3
#endif /* __BLOCKS__ */

static pthread_mutex_t atexit_mutex = PTHREAD_MUTEX_INITIALIZER;

#define _MUTEX_LOCK(x)		if (__isthreaded) _pthread_mutex_lock(x)
#define _MUTEX_UNLOCK(x)	if (__isthreaded) _pthread_mutex_unlock(x)

struct atexit {
	struct atexit *next;			/* next in list */
	int ind;				/* next index in this table */
	struct atexit_fn {
		int fn_type;			/* ATEXIT_? from above */
		union {
			void (*std_func)(void);
			void (*cxa_func)(void *);
#ifdef __BLOCKS__
			void (^block)(void);
#endif /* __BLOCKS__ */
		} fn_ptr;			/* function pointer */
		void *fn_arg;			/* argument for CXA callback */
		void *fn_dso;			/* shared module handle */
	} fns[ATEXIT_SIZE];			/* the table itself */
};

static struct atexit *__atexit;		/* points to head of LIFO stack */
static int new_registration;

/*
 * Register the function described by 'fptr' to be called at application
 * exit or owning shared object unload time. This is a helper function
 * for atexit and __cxa_atexit.
 */
static int
atexit_register(struct atexit_fn *fptr)
{
	static struct atexit __atexit0;	/* one guaranteed table */
	struct atexit *p;

	_MUTEX_LOCK(&atexit_mutex);
	if ((p = __atexit) == NULL)
		__atexit = p = &__atexit0;
	else while (p->ind >= ATEXIT_SIZE) {
		struct atexit *old__atexit;
		old__atexit = __atexit;
	        _MUTEX_UNLOCK(&atexit_mutex);
		if ((p = (struct atexit *)malloc(sizeof(*p))) == NULL)
			return (-1);
		_MUTEX_LOCK(&atexit_mutex);
		if (old__atexit != __atexit) {
			/* Lost race, retry operation */
			_MUTEX_UNLOCK(&atexit_mutex);
			free(p);
			_MUTEX_LOCK(&atexit_mutex);
			p = __atexit;
			continue;
		}
		p->ind = 0;
		p->next = __atexit;
		__atexit = p;
	}
	p->fns[p->ind++] = *fptr;
	new_registration = 1;
	_MUTEX_UNLOCK(&atexit_mutex);
	return 0;
}

/*
 * Register a function to be performed at exit.
 */
int
atexit(void (*func)(void))
{
	struct atexit_fn fn;
	struct dl_info info;
	int error;

	fn.fn_type = ATEXIT_FN_STD;
	fn.fn_ptr.std_func = func;
	fn.fn_arg = NULL;
#if defined(__DYNAMIC__)
	if ( dladdr(func, &info) )
		fn.fn_dso = info.dli_fbase;
	else 
		fn.fn_dso = NULL;
#else /* ! defined(__DYNAMIC__) */
	fn.fn_dso = NULL;
#endif /* defined(__DYNAMIC__) */

 	error = atexit_register(&fn);	
	return (error);
}

#ifdef __BLOCKS__
int
atexit_b(void (^block)(void))
{
	struct atexit_fn fn;
	struct dl_info info;
	int error;

	fn.fn_type = ATEXIT_FN_BLK;
	fn.fn_ptr.block = Block_copy(block);
	fn.fn_arg = NULL;
#if defined(__DYNAMIC__)
	if ( dladdr(block, &info) )
		fn.fn_dso = info.dli_fbase;
	else 
		fn.fn_dso = NULL;
#else /* ! defined(__DYNAMIC__) */
	fn.fn_dso = NULL;
#endif /* defined(__DYNAMIC__) */

 	error = atexit_register(&fn);	
	return (error);
}
#endif /* __BLOCKS__ */

/*
 * Register a function to be performed at exit or when an shared object
 * with given dso handle is unloaded dynamically.
 */
int
__cxa_atexit(void (*func)(void *), void *arg, void *dso)
{
	struct atexit_fn fn;
	int error;

	fn.fn_type = ATEXIT_FN_CXA;
	fn.fn_ptr.cxa_func = func;;
	fn.fn_arg = arg;
	fn.fn_dso = dso;

 	error = atexit_register(&fn);	
	return (error);
}

/*
 * Call all handlers registered with __cxa_atexit for the shared
 * object owning 'dso'.  Note: if 'dso' is NULL, then all remaining
 * handlers are called.
 */
void
__cxa_finalize(const void *dso)
{
	struct atexit *p;
	struct atexit_fn fn;
	int n;

	_MUTEX_LOCK(&atexit_mutex);
restart:
	for (p = __atexit; p; p = p->next) {
		for (n = p->ind; --n >= 0;) {
			if (p->fns[n].fn_type == ATEXIT_FN_EMPTY)
				continue; /* already been called */
			if (dso != NULL && dso != p->fns[n].fn_dso)
				continue; /* wrong DSO */
			fn = p->fns[n];
			/*
			  Mark entry to indicate that this particular handler
			  has already been called.
			*/
			p->fns[n].fn_type = ATEXIT_FN_EMPTY;
			new_registration = 0;
		        _MUTEX_UNLOCK(&atexit_mutex);
		
			/* Call the function of correct type. */
			if (fn.fn_type == ATEXIT_FN_CXA)
				fn.fn_ptr.cxa_func(fn.fn_arg);
			else if (fn.fn_type == ATEXIT_FN_STD)
				fn.fn_ptr.std_func();
#ifdef __BLOCKS__
			else if (fn.fn_type == ATEXIT_FN_BLK)
				fn.fn_ptr.block();
#endif /* __BLOCKS__ */
			_MUTEX_LOCK(&atexit_mutex);
			if (new_registration)
			    goto restart;
		}
	}
	_MUTEX_UNLOCK(&atexit_mutex);
}
Commit	Line	Data
9385eb3d	1	/*-
e9ce8d39 A	2	* Copyright (c) 1990, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* This code is derived from software contributed to Berkeley by
	6	* Chris Torek.
	7	*
	8	* Redistribution and use in source and binary forms, with or without
	9	* modification, are permitted provided that the following conditions
	10	* are met:
	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
e9ce8d39 A	16	* 4. Neither the name of the University nor the names of its contributors
	17	* may be used to endorse or promote products derived from this software
	18	* without specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	* SUCH DAMAGE.
	31	*/
	32
9385eb3d A	33	#if defined(LIBC_SCCS) && !defined(lint)
	34	static char sccsid[] = "@(#)atexit.c 8.2 (Berkeley) 7/3/94";
	35	#endif /* LIBC_SCCS and not lint */
	36	#include <sys/cdefs.h>
1f2f436a	37	__FBSDID("$FreeBSD: src/lib/libc/stdlib/atexit.c,v 1.8 2007/01/09 00:28:09 imp Exp $");
e9ce8d39	38
9385eb3d	39	#include "namespace.h"
e9ce8d39 A	40	#include <stddef.h>
e9ce8d39 A	41	#include <stdlib.h>
9385eb3d A	42	#include <unistd.h>
9385eb3d A	43	#include <pthread.h>
ad3c9f2a A	44	#if defined(__DYNAMIC__) \|\| defined (__BLOCKS__)
	45	#include <dlfcn.h>
	46	#endif /* defined(__DYNAMIC__) */
e9ce8d39	47	#include "atexit.h"
9385eb3d A	48	#include "un-namespace.h"
9385eb3d A	49
ad3c9f2a A	50	#ifdef __BLOCKS__
	51	#include <Block.h>
	52	#endif /* __BLOCKS__ */
9385eb3d A	53	#include "libc_private.h"
9385eb3d A	54
59e0d9fe A	55	#define ATEXIT_FN_EMPTY 0
	56	#define ATEXIT_FN_STD 1
	57	#define ATEXIT_FN_CXA 2
ad3c9f2a A	58	#ifdef __BLOCKS__
	59	#define ATEXIT_FN_BLK 3
	60	#endif /* __BLOCKS__ */
59e0d9fe	61
9385eb3d A	62	static pthread_mutex_t atexit_mutex = PTHREAD_MUTEX_INITIALIZER;
	63
	64	#define _MUTEX_LOCK(x) if (__isthreaded) _pthread_mutex_lock(x)
	65	#define _MUTEX_UNLOCK(x) if (__isthreaded) _pthread_mutex_unlock(x)
e9ce8d39	66
59e0d9fe A	67	struct atexit {
	68	struct atexit next; / next in list */
	69	int ind; /* next index in this table */
	70	struct atexit_fn {
	71	int fn_type; /* ATEXIT_? from above */
	72	union {
	73	void (*std_func)(void);
	74	void (cxa_func)(void );
ad3c9f2a A	75	#ifdef __BLOCKS__
	76	void (^block)(void);
	77	#endif /* __BLOCKS__ */
59e0d9fe A	78	} fn_ptr; /* function pointer */
	79	void fn_arg; / argument for CXA callback */
	80	void fn_dso; / shared module handle */
	81	} fns[ATEXIT_SIZE]; /* the table itself */
	82	};
	83
	84	static struct atexit __atexit; / points to head of LIFO stack */
ad3c9f2a	85	static int new_registration;
e9ce8d39 A	86
e9ce8d39 A	87	/*
59e0d9fe A	88	* Register the function described by 'fptr' to be called at application
	89	* exit or owning shared object unload time. This is a helper function
	90	* for atexit and __cxa_atexit.
e9ce8d39	91	*/
59e0d9fe A	92	static int
59e0d9fe A	93	atexit_register(struct atexit_fn *fptr)
e9ce8d39 A	94	{
e9ce8d39 A	95	static struct atexit __atexit0; /* one guaranteed table */
9385eb3d	96	struct atexit *p;
e9ce8d39	97
9385eb3d	98	_MUTEX_LOCK(&atexit_mutex);
e9ce8d39 A	99	if ((p = __atexit) == NULL)
e9ce8d39 A	100	__atexit = p = &__atexit0;
9385eb3d A	101	else while (p->ind >= ATEXIT_SIZE) {
	102	struct atexit *old__atexit;
	103	old__atexit = __atexit;
	104	_MUTEX_UNLOCK(&atexit_mutex);
	105	if ((p = (struct atexit )malloc(sizeof(p))) == NULL)
e9ce8d39	106	return (-1);
9385eb3d A	107	_MUTEX_LOCK(&atexit_mutex);
	108	if (old__atexit != __atexit) {
	109	/* Lost race, retry operation */
	110	_MUTEX_UNLOCK(&atexit_mutex);
	111	free(p);
	112	_MUTEX_LOCK(&atexit_mutex);
	113	p = __atexit;
	114	continue;
	115	}
e9ce8d39 A	116	p->ind = 0;
	117	p->next = __atexit;
	118	__atexit = p;
	119	}
59e0d9fe	120	p->fns[p->ind++] = *fptr;
ad3c9f2a	121	new_registration = 1;
59e0d9fe A	122	_MUTEX_UNLOCK(&atexit_mutex);
	123	return 0;
	124	}
	125
	126	/*
	127	* Register a function to be performed at exit.
	128	*/
	129	int
	130	atexit(void (*func)(void))
	131	{
	132	struct atexit_fn fn;
ad3c9f2a	133	struct dl_info info;
59e0d9fe A	134	int error;
	135
	136	fn.fn_type = ATEXIT_FN_STD;
ad3c9f2a	137	fn.fn_ptr.std_func = func;
59e0d9fe	138	fn.fn_arg = NULL;
ad3c9f2a A	139	#if defined(__DYNAMIC__)
	140	if ( dladdr(func, &info) )
	141	fn.fn_dso = info.dli_fbase;
	142	else
	143	fn.fn_dso = NULL;
	144	#else /* ! defined(__DYNAMIC__) */
59e0d9fe	145	fn.fn_dso = NULL;
ad3c9f2a	146	#endif /* defined(__DYNAMIC__) */
59e0d9fe A	147
	148	error = atexit_register(&fn);
	149	return (error);
	150	}
	151
ad3c9f2a A	152	#ifdef __BLOCKS__
	153	int
	154	atexit_b(void (^block)(void))
	155	{
	156	struct atexit_fn fn;
	157	struct dl_info info;
	158	int error;
	159
	160	fn.fn_type = ATEXIT_FN_BLK;
	161	fn.fn_ptr.block = Block_copy(block);
	162	fn.fn_arg = NULL;
	163	#if defined(__DYNAMIC__)
	164	if ( dladdr(block, &info) )
	165	fn.fn_dso = info.dli_fbase;
	166	else
	167	fn.fn_dso = NULL;
	168	#else /* ! defined(__DYNAMIC__) */
	169	fn.fn_dso = NULL;
	170	#endif /* defined(__DYNAMIC__) */
	171
	172	error = atexit_register(&fn);
	173	return (error);
	174	}
	175	#endif /* __BLOCKS__ */
	176
59e0d9fe A	177	/*
	178	* Register a function to be performed at exit or when an shared object
	179	* with given dso handle is unloaded dynamically.
	180	*/
	181	int
	182	__cxa_atexit(void (func)(void ), void arg, void dso)
	183	{
	184	struct atexit_fn fn;
	185	int error;
	186
	187	fn.fn_type = ATEXIT_FN_CXA;
	188	fn.fn_ptr.cxa_func = func;;
	189	fn.fn_arg = arg;
	190	fn.fn_dso = dso;
	191
	192	error = atexit_register(&fn);
	193	return (error);
	194	}
	195
	196	/*
	197	* Call all handlers registered with __cxa_atexit for the shared
	198	* object owning 'dso'. Note: if 'dso' is NULL, then all remaining
	199	* handlers are called.
	200	*/
	201	void
ad3c9f2a	202	__cxa_finalize(const void *dso)
59e0d9fe A	203	{
	204	struct atexit *p;
	205	struct atexit_fn fn;
	206	int n;
	207
	208	_MUTEX_LOCK(&atexit_mutex);
ad3c9f2a	209	restart:
59e0d9fe A	210	for (p = __atexit; p; p = p->next) {
	211	for (n = p->ind; --n >= 0;) {
	212	if (p->fns[n].fn_type == ATEXIT_FN_EMPTY)
	213	continue; /* already been called */
	214	if (dso != NULL && dso != p->fns[n].fn_dso)
	215	continue; /* wrong DSO */
	216	fn = p->fns[n];
	217	/*
	218	Mark entry to indicate that this particular handler
	219	has already been called.
	220	*/
	221	p->fns[n].fn_type = ATEXIT_FN_EMPTY;
ad3c9f2a	222	new_registration = 0;
59e0d9fe A	223	_MUTEX_UNLOCK(&atexit_mutex);
	224
	225	/* Call the function of correct type. */
	226	if (fn.fn_type == ATEXIT_FN_CXA)
	227	fn.fn_ptr.cxa_func(fn.fn_arg);
	228	else if (fn.fn_type == ATEXIT_FN_STD)
	229	fn.fn_ptr.std_func();
ad3c9f2a A	230	#ifdef __BLOCKS__
	231	else if (fn.fn_type == ATEXIT_FN_BLK)
	232	fn.fn_ptr.block();
	233	#endif /* __BLOCKS__ */
59e0d9fe	234	_MUTEX_LOCK(&atexit_mutex);
ad3c9f2a A	235	if (new_registration)
ad3c9f2a A	236	goto restart;
59e0d9fe A	237	}
59e0d9fe A	238	}
9385eb3d	239	_MUTEX_UNLOCK(&atexit_mutex);
e9ce8d39	240	}