Loading...
stdlib/FreeBSD/atexit.c /dev/null Libc-498
--- /dev/null
+++ Libc/Libc-498/stdlib/FreeBSD/atexit.c
@@ -0,0 +1,189 @@
+/*-
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 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 1.7 2003/12/19 17:11:20 kan Exp $");
+
+#include "namespace.h"
+#include <stddef.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <pthread.h>
+#include "atexit.h"
+#include "un-namespace.h"
+
+#include "libc_private.h"
+
+#define	ATEXIT_FN_EMPTY	0
+#define	ATEXIT_FN_STD	1
+#define	ATEXIT_FN_CXA	2
+
+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 *);
+		} 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 */
+
+/*
+ * 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;
+	_MUTEX_UNLOCK(&atexit_mutex);
+	return 0;
+}
+
+/*
+ * Register a function to be performed at exit.
+ */
+int
+atexit(void (*func)(void))
+{
+	struct atexit_fn fn;
+	int error;
+
+	fn.fn_type = ATEXIT_FN_STD;
+	fn.fn_ptr.std_func = func;;
+	fn.fn_arg = NULL;
+	fn.fn_dso = NULL;
+
+ 	error = atexit_register(&fn);	
+	return (error);
+}
+
+/*
+ * 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(void *dso)
+{
+	struct atexit *p;
+	struct atexit_fn fn;
+	int n;
+
+	_MUTEX_LOCK(&atexit_mutex);
+	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;
+		        _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();
+			_MUTEX_LOCK(&atexit_mutex);
+		}
+	}
+	_MUTEX_UNLOCK(&atexit_mutex);
+}