Gecko [ goons4good.org ]

Name	Size	Permission	Date
aes.h	1.05 KB	-rw-r--r--	2025-03-04 05:23
app.h	10.23 KB	-rw-r--r--	2025-03-04 05:23
assertions.h	2.78 KB	-rw-r--r--	2025-03-04 05:23
atomic.h	4.15 KB	-rw-r--r--	2025-03-04 05:23
backtrace.h	3.8 KB	-rw-r--r--	2025-03-04 05:23
base32.h	3.94 KB	-rw-r--r--	2025-03-04 05:23
base64.h	2.39 KB	-rw-r--r--	2025-03-04 05:23
bind9.h	849 B	-rw-r--r--	2025-03-04 05:23
boolean.h	746 B	-rw-r--r--	2025-03-04 05:23
buffer.h	25.69 KB	-rw-r--r--	2025-03-04 05:23
bufferlist.h	1.42 KB	-rw-r--r--	2025-03-04 05:23
commandline.h	1.69 KB	-rw-r--r--	2025-03-04 05:23
condition.h	1.44 KB	-rw-r--r--	2025-03-04 05:23
counter.h	1.88 KB	-rw-r--r--	2025-03-04 05:23
crc64.h	986 B	-rw-r--r--	2025-03-04 05:23
deprecated.h	622 B	-rw-r--r--	2025-03-04 05:23
dir.h	1.96 KB	-rw-r--r--	2025-03-04 05:23
entropy.h	8.76 KB	-rw-r--r--	2025-03-04 05:23
errno.h	658 B	-rw-r--r--	2025-03-04 05:23
errno2result.h	893 B	-rw-r--r--	2025-03-04 05:23
error.h	1.4 KB	-rw-r--r--	2025-03-04 05:23
event.h	2.98 KB	-rw-r--r--	2025-03-04 05:23
eventclass.h	1.35 KB	-rw-r--r--	2025-03-04 05:23
file.h	11.43 KB	-rw-r--r--	2025-03-04 05:23
formatcheck.h	892 B	-rw-r--r--	2025-03-04 05:23
fsaccess.h	7.25 KB	-rw-r--r--	2025-03-04 05:23
hash.h	7.52 KB	-rw-r--r--	2025-03-04 05:23
heap.h	5.14 KB	-rw-r--r--	2025-03-04 05:23
hex.h	2.33 KB	-rw-r--r--	2025-03-04 05:23
hmacmd5.h	1.75 KB	-rw-r--r--	2025-03-04 05:23
hmacsha.h	4.44 KB	-rw-r--r--	2025-03-04 05:23
ht.h	4.29 KB	-rw-r--r--	2025-03-04 05:23
httpd.h	2.26 KB	-rw-r--r--	2025-03-04 05:23
int.h	1.37 KB	-rw-r--r--	2025-03-04 05:23
interfaceiter.h	3.03 KB	-rw-r--r--	2025-03-04 05:23
iterated_hash.h	1.02 KB	-rw-r--r--	2025-03-04 05:23
json.h	1.42 KB	-rw-r--r--	2025-03-04 05:23
keyboard.h	976 B	-rw-r--r--	2025-03-04 05:23
lang.h	636 B	-rw-r--r--	2025-03-04 05:23
lex.h	9.42 KB	-rw-r--r--	2025-03-04 05:23
lfsr.h	2.88 KB	-rw-r--r--	2025-03-04 05:23
lib.h	1.04 KB	-rw-r--r--	2025-03-04 05:23
likely.h	718 B	-rw-r--r--	2025-03-04 05:23
list.h	5.65 KB	-rw-r--r--	2025-03-04 05:23
log.h	28.06 KB	-rw-r--r--	2025-03-04 05:23
magic.h	993 B	-rw-r--r--	2025-03-04 05:23
md5.h	2.34 KB	-rw-r--r--	2025-03-04 05:23
mem.h	20.63 KB	-rw-r--r--	2025-03-04 05:23
meminfo.h	690 B	-rw-r--r--	2025-03-04 05:23
msgcat.h	2.66 KB	-rw-r--r--	2025-03-04 05:23
msgs.h	8.22 KB	-rw-r--r--	2025-03-04 05:23
mutex.h	3.44 KB	-rw-r--r--	2025-03-04 05:23
mutexblock.h	1.34 KB	-rw-r--r--	2025-03-04 05:23
net.h	10.32 KB	-rw-r--r--	2025-03-04 05:23
netaddr.h	4.56 KB	-rw-r--r--	2025-03-04 05:23
netdb.h	862 B	-rw-r--r--	2025-03-04 05:23
netscope.h	947 B	-rw-r--r--	2025-03-04 05:23
offset.h	699 B	-rw-r--r--	2025-03-04 05:23
once.h	981 B	-rw-r--r--	2025-03-04 05:23
ondestroy.h	2.79 KB	-rw-r--r--	2025-03-04 05:23
os.h	670 B	-rw-r--r--	2025-03-04 05:23
parseint.h	1.49 KB	-rw-r--r--	2025-03-04 05:23
platform.h	9.31 KB	-rw-r--r--	2025-03-04 05:23
pool.h	3.42 KB	-rw-r--r--	2025-03-04 05:23
portset.h	3.21 KB	-rw-r--r--	2025-03-04 05:23
print.h	2.49 KB	-rw-r--r--	2025-03-04 05:23
queue.h	4.66 KB	-rw-r--r--	2025-03-04 05:23
quota.h	2.29 KB	-rw-r--r--	2025-03-04 05:23
radix.h	6.37 KB	-rw-r--r--	2025-03-04 05:23
random.h	2.99 KB	-rw-r--r--	2025-03-04 05:23
ratelimiter.h	3.38 KB	-rw-r--r--	2025-03-04 05:23
refcount.h	7.89 KB	-rw-r--r--	2025-03-04 05:23
regex.h	766 B	-rw-r--r--	2025-03-04 05:23
region.h	1.99 KB	-rw-r--r--	2025-03-04 05:23
resource.h	2.8 KB	-rw-r--r--	2025-03-04 05:23
result.h	4.62 KB	-rw-r--r--	2025-03-04 05:23
resultclass.h	1.56 KB	-rw-r--r--	2025-03-04 05:23
rwlock.h	3.6 KB	-rw-r--r--	2025-03-04 05:23
safe.h	1.21 KB	-rw-r--r--	2025-03-04 05:23
serial.h	1.4 KB	-rw-r--r--	2025-03-04 05:23
sha1.h	1.52 KB	-rw-r--r--	2025-03-04 05:23
sha2.h	5.65 KB	-rw-r--r--	2025-03-04 05:23
sockaddr.h	6 KB	-rw-r--r--	2025-03-04 05:23
socket.h	35.81 KB	-rw-r--r--	2025-03-04 05:23
stat.h	805 B	-rw-r--r--	2025-03-04 05:23
stats.h	3.02 KB	-rw-r--r--	2025-03-04 05:23
stdio.h	1.74 KB	-rw-r--r--	2025-03-04 05:23
stdlib.h	703 B	-rw-r--r--	2025-03-04 05:23
stdtime.h	1.3 KB	-rw-r--r--	2025-03-04 05:23
strerror.h	776 B	-rw-r--r--	2025-03-04 05:23
string.h	5.94 KB	-rw-r--r--	2025-03-04 05:23
symtab.h	4.21 KB	-rw-r--r--	2025-03-04 05:23
syslog.h	843 B	-rw-r--r--	2025-03-04 05:23
task.h	21.08 KB	-rw-r--r--	2025-03-04 05:23
taskpool.h	3.61 KB	-rw-r--r--	2025-03-04 05:23
thread.h	1.47 KB	-rw-r--r--	2025-03-04 05:23
time.h	8.66 KB	-rw-r--r--	2025-03-04 05:23
timer.h	10.54 KB	-rw-r--r--	2025-03-04 05:23
tm.h	894 B	-rw-r--r--	2025-03-04 05:23
types.h	5.54 KB	-rw-r--r--	2025-03-04 05:23
util.h	7.49 KB	-rw-r--r--	2025-03-04 05:23
version.h	688 B	-rw-r--r--	2025-03-04 05:23
xml.h	1.07 KB	-rw-r--r--	2025-03-04 05:23

Rename

/*
 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * See the COPYRIGHT file distributed with this work for additional
 * information regarding copyright ownership.
 */

#ifndef ISC_RWLOCK_H
#define ISC_RWLOCK_H 1

/*! \file isc/rwlock.h */

#include <isc/condition.h>
#include <isc/lang.h>
#include <isc/platform.h>
#include <isc/types.h>

#if defined(ISC_PLATFORM_HAVESTDATOMIC)
#include <stdint.h>
#include <stdatomic.h>
#endif

ISC_LANG_BEGINDECLS

typedef enum {
	isc_rwlocktype_none = 0,
	isc_rwlocktype_read,
	isc_rwlocktype_write
} isc_rwlocktype_t;

#ifdef ISC_PLATFORM_USETHREADS
#if (defined(ISC_PLATFORM_HAVESTDATOMIC) && defined(ATOMIC_INT_LOCK_FREE)) || (defined(ISC_PLATFORM_HAVEXADD) && defined(ISC_PLATFORM_HAVECMPXCHG))
#define ISC_RWLOCK_USEATOMIC 1
#if (defined(ISC_PLATFORM_HAVESTDATOMIC) && defined(ATOMIC_INT_LOCK_FREE))
#define ISC_RWLOCK_USESTDATOMIC 1
#endif
#endif

struct isc_rwlock {
	/* Unlocked. */
	unsigned int		magic;
	isc_mutex_t		lock;
	isc_int32_t		spins;

#if defined(ISC_RWLOCK_USEATOMIC)
	/*
	 * When some atomic instructions with hardware assistance are
	 * available, rwlock will use those so that concurrent readers do not
	 * interfere with each other through mutex as long as no writers
	 * appear, massively reducing the lock overhead in the typical case.
	 *
	 * The basic algorithm of this approach is the "simple
	 * writer-preference lock" shown in the following URL:
	 * http://www.cs.rochester.edu/u/scott/synchronization/pseudocode/rw.html
	 * but our implementation does not rely on the spin lock unlike the
	 * original algorithm to be more portable as a user space application.
	 */

/* Read or modified atomically. */
#if defined(ISC_RWLOCK_USESTDATOMIC)
	atomic_int_fast32_t	write_requests;
	atomic_int_fast32_t	write_completions;
	atomic_int_fast32_t	cnt_and_flag;
#else
	isc_int32_t		write_requests;
	isc_int32_t		write_completions;
	isc_int32_t		cnt_and_flag;
#endif

/* Locked by lock. */
	isc_condition_t		readable;
	isc_condition_t		writeable;
	unsigned int		readers_waiting;

/* Locked by rwlock itself. */
	unsigned int		write_granted;

/* Unlocked. */
	unsigned int		write_quota;

#else  /* ISC_RWLOCK_USEATOMIC */

/*%< Locked by lock. */
	isc_condition_t		readable;
	isc_condition_t		writeable;
	isc_rwlocktype_t	type;

/*% The number of threads that have the lock. */
	unsigned int		active;

/*%
	 * The number of lock grants made since the lock was last switched
	 * from reading to writing or vice versa; used in determining
	 * when the quota is reached and it is time to switch.
	 */
	unsigned int		granted;

unsigned int		readers_waiting;
	unsigned int		writers_waiting;
	unsigned int		read_quota;
	unsigned int		write_quota;
	isc_rwlocktype_t	original;
#endif  /* ISC_RWLOCK_USEATOMIC */
};
#else /* ISC_PLATFORM_USETHREADS */
struct isc_rwlock {
	unsigned int		magic;
	isc_rwlocktype_t	type;
	unsigned int		active;
};
#endif /* ISC_PLATFORM_USETHREADS */

isc_result_t
isc_rwlock_init(isc_rwlock_t *rwl, unsigned int read_quota,
		unsigned int write_quota);

isc_result_t
isc_rwlock_lock(isc_rwlock_t *rwl, isc_rwlocktype_t type);

isc_result_t
isc_rwlock_trylock(isc_rwlock_t *rwl, isc_rwlocktype_t type);

isc_result_t
isc_rwlock_unlock(isc_rwlock_t *rwl, isc_rwlocktype_t type);

isc_result_t
isc_rwlock_tryupgrade(isc_rwlock_t *rwl);

void
isc_rwlock_downgrade(isc_rwlock_t *rwl);

void
isc_rwlock_destroy(isc_rwlock_t *rwl);

ISC_LANG_ENDDECLS

#endif /* ISC_RWLOCK_H */