[apple/xnu.git] / bsd / net / init.c

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#include <kern/kalloc.h>
#include <libkern/OSAtomic.h>
#include <sys/errno.h>
#include <net/init.h>
#include <libkern/libkern.h>
#include <string.h>

struct init_list_entry {
	struct init_list_entry	*next;
	net_init_func_ptr		func;
};

#define LIST_RAN ((struct init_list_entry*)0xffffffff)
static struct init_list_entry	*list_head = 0;

errno_t
net_init_add(
	net_init_func_ptr init_func)
{
	struct init_list_entry	*entry;
	
	if (init_func == 0) {
		return EINVAL;
	}
	
	/* Check if we've already started */
	if (list_head == LIST_RAN) {
		return EALREADY;
	}
	
	entry = kalloc(sizeof(*entry));
	if (entry == 0) {
		printf("net_init_add: no memory\n");
		return ENOMEM;
	}
	
	bzero(entry, sizeof(*entry));
	entry->func = init_func;
	
	do {
		entry->next = list_head;
		
		if (entry->next == LIST_RAN) {
			/* List already ran, cleanup and call the function */
			kfree(entry, sizeof(*entry));
			return EALREADY;
		}
	} while(!OSCompareAndSwap((UInt32)entry->next, (UInt32)entry,
							  (UInt32*)&list_head));
	
	return 0;
}

__private_extern__ void
net_init_run(void)
{
	struct init_list_entry	*backward_head = 0;
	struct init_list_entry	*forward_head = 0;
	struct init_list_entry	*current = 0;
	
	/*
	 * Grab the list, replacing the head with 0xffffffff to indicate
	 * that we've already run.
	 */
	do {
		backward_head = list_head;
	} while (!OSCompareAndSwap((UInt32)backward_head, (UInt32)LIST_RAN,
							   (UInt32*)&list_head));
	
	/* Reverse the order of the list */
	while (backward_head != 0) {
		current = backward_head;
		backward_head = current->next;
		current->next = forward_head;
		forward_head = current;
	}
	
	/* Call each function pointer registered */
	while (forward_head != 0) {
		current = forward_head;
		forward_head = current->next;
		current->func();
		kfree(current, sizeof(*current));
	}
}
Commit	Line	Data
91447636	1	/*
5d5c5d0d A	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
5d5c5d0d A	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
91447636	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
8f6c56a5	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
91447636 A	27	*/
	28
	29	#include <kern/kalloc.h>
	30	#include <libkern/OSAtomic.h>
	31	#include <sys/errno.h>
	32	#include <net/init.h>
	33	#include <libkern/libkern.h>
	34	#include <string.h>
	35
	36	struct init_list_entry {
	37	struct init_list_entry *next;
	38	net_init_func_ptr func;
	39	};
	40
	41	#define LIST_RAN ((struct init_list_entry*)0xffffffff)
	42	static struct init_list_entry *list_head = 0;
	43
	44	errno_t
	45	net_init_add(
	46	net_init_func_ptr init_func)
	47	{
	48	struct init_list_entry *entry;
	49
	50	if (init_func == 0) {
	51	return EINVAL;
	52	}
	53
	54	/* Check if we've already started */
	55	if (list_head == LIST_RAN) {
	56	return EALREADY;
	57	}
	58
	59	entry = kalloc(sizeof(*entry));
	60	if (entry == 0) {
	61	printf("net_init_add: no memory\n");
	62	return ENOMEM;
	63	}
	64
	65	bzero(entry, sizeof(*entry));
	66	entry->func = init_func;
	67
	68	do {
	69	entry->next = list_head;
	70
	71	if (entry->next == LIST_RAN) {
	72	/* List already ran, cleanup and call the function */
	73	kfree(entry, sizeof(*entry));
	74	return EALREADY;
	75	}
	76	} while(!OSCompareAndSwap((UInt32)entry->next, (UInt32)entry,
	77	(UInt32*)&list_head));
	78
	79	return 0;
	80	}
	81
	82	__private_extern__ void
	83	net_init_run(void)
	84	{
	85	struct init_list_entry *backward_head = 0;
	86	struct init_list_entry *forward_head = 0;
	87	struct init_list_entry *current = 0;
	88
	89	/*
	90	* Grab the list, replacing the head with 0xffffffff to indicate
91	* that we've already run.
92	*/
93	do {
94	backward_head = list_head;
95	} while (!OSCompareAndSwap((UInt32)backward_head, (UInt32)LIST_RAN,
96	(UInt32*)&list_head));
97
98	/* Reverse the order of the list */
99	while (backward_head != 0) {
100	current = backward_head;
101	backward_head = current->next;
102	current->next = forward_head;
103	forward_head = current;
104	}
105
106	/* Call each function pointer registered */
107	while (forward_head != 0) {
108	current = forward_head;
109	forward_head = current->next;
110	current->func();
111	kfree(current, sizeof(*current));
112	}
113	}