libc/dns/net/reentrant.h - android_bionic - Gitiles

 /*	$NetBSD: reentrant.h,v 1.10 2004/12/14 00:23:19 nathanw Exp $	*/

 /*-
  * Copyright (c) 1997, 1998, 2003 The NetBSD Foundation, Inc.
  * All rights reserved.
  *
  * This code is derived from software contributed to The NetBSD Foundation
  * by J.T. Conklin, by Nathan J. Williams, and by Jason R. Thorpe.
  *
  * 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 NetBSD
  *        Foundation, Inc. and its contributors.
  * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
  */

 /*
  * Requirements:
  *
  * 1. The thread safe mechanism should be lightweight so the library can
  *    be used by non-threaded applications without unreasonable overhead.
  *
  * 2. There should be no dependency on a thread engine for non-threaded
  *    applications.
  *
  * 3. There should be no dependency on any particular thread engine.
  *
  * 4. The library should be able to be compiled without support for thread
  *    safety.
  *
  *
  * Rationale:
  *
  * One approach for thread safety is to provide discrete versions of the
  * library: one thread safe, the other not.  The disadvantage of this is
  * that libc is rather large, and two copies of a library which are 99%+
  * identical is not an efficent use of resources.
  *
  * Another approach is to provide a single thread safe library.  However,
  * it should not add significant run time or code size overhead to non-
  * threaded applications.
  *
  * Since the NetBSD C library is used in other projects, it should be
  * easy to replace the mutual exclusion primitives with ones provided by
  * another system.  Similarly, it should also be easy to remove all
  * support for thread safety completely if the target environment does
  * not support threads.
  *
  *
  * Implementation Details:
  *
  * The thread primitives used by the library (mutex_t, mutex_lock, etc.)
  * are macros which expand to the cooresponding primitives provided by
  * the thread engine or to nothing.  The latter is used so that code is
  * not unreasonably cluttered with #ifdefs when all thread safe support
  * is removed.
  *
  * The thread macros can be directly mapped to the mutex primitives from
  * pthreads, however it should be reasonably easy to wrap another mutex
  * implementation so it presents a similar interface.
  *
  * The thread functions operate by dispatching to symbols which are, by
  * default, weak-aliased to no-op functions in thread-stub/thread-stub.c
  * (some uses of thread operations are conditional on __isthreaded, but
  * not all of them are).
  *
  * When the thread library is linked in, it provides strong-alias versions
  * of those symbols which dispatch to its own real thread operations.
  *
  */

 #ifdef _REENTRANT

 /*
  * Abtract thread interface for thread-safe libraries.  These routines
  * will use stubs in libc if the application is not linked against the
  * pthread library, and the real function in the pthread library if it
  * is.
  */

 #include <pthread.h>
 #include <signal.h>
 #include <sys/cdefs.h>

 #define	mutex_t			pthread_mutex_t
 #define	MUTEX_INITIALIZER	PTHREAD_MUTEX_INITIALIZER

 #define	mutexattr_t		pthread_mutexattr_t

 #define	MUTEX_TYPE_NORMAL	PTHREAD_MUTEX_NORMAL
 #define	MUTEX_TYPE_ERRORCHECK	PTHREAD_MUTEX_ERRORCHECK
 #define	MUTEX_TYPE_RECURSIVE	PTHREAD_MUTEX_RECURSIVE

 #define	cond_t			pthread_cond_t
 #define	COND_INITIALIZER	PTHREAD_COND_INITIALIZER

 #define	condattr_t		pthread_condattr_t

 #define	rwlock_t		pthread_rwlock_t
 #define	RWLOCK_INITIALIZER	PTHREAD_RWLOCK_INITIALIZER

 #define	rwlockattr_t		pthread_rwlockattr_t

 #define	thread_key_t		pthread_key_t

 #define	thr_t			pthread_t

 #define	thrattr_t		pthread_attr_t

 #define	once_t			pthread_once_t
 #define	ONCE_INITIALIZER	PTHREAD_ONCE_INIT

 #ifndef __LIBC_THREAD_STUBS

 __BEGIN_DECLS
 int	__libc_mutex_init(mutex_t *, const mutexattr_t *);
 int	__libc_mutex_lock(mutex_t *);
 int	__libc_mutex_trylock(mutex_t *);
 int	__libc_mutex_unlock(mutex_t *);
 int	__libc_mutex_destroy(mutex_t *);

 int	__libc_mutexattr_init(mutexattr_t *);
 int	__libc_mutexattr_settype(mutexattr_t *, int);
 int	__libc_mutexattr_destroy(mutexattr_t *);
 __END_DECLS

 #define	mutex_init(m, a)	__libc_mutex_init((m), (a))
 #define	mutex_lock(m)		__libc_mutex_lock((m))
 #define	mutex_trylock(m)	__libc_mutex_trylock((m))
 #define	mutex_unlock(m)		__libc_mutex_unlock((m))
 #define	mutex_destroy(m)	__libc_mutex_destroy((m))

 #define	mutexattr_init(ma)	__libc_mutexattr_init((ma))
 #define	mutexattr_settype(ma, t) __libc_mutexattr_settype((ma), (t))
 #define	mutexattr_destroy(ma)	__libc_mutexattr_destroy((ma))

 __BEGIN_DECLS
 int	__libc_cond_init(cond_t *, const condattr_t *);
 int	__libc_cond_signal(cond_t *);
 int	__libc_cond_broadcast(cond_t *);
 int	__libc_cond_wait(cond_t *, mutex_t *);
 int	__libc_cond_timedwait(cond_t *, mutex_t *, const struct timespec *);
 int	__libc_cond_destroy(cond_t *);
 __END_DECLS

 #define	cond_init(c, t, a)     	__libc_cond_init((c), (a))
 #define	cond_signal(c)		__libc_cond_signal((c))
 #define	cond_broadcast(c)	__libc_cond_broadcast((c))
 #define	cond_wait(c, m)		__libc_cond_wait((c), (m))
 #define	cond_timedwait(c, m, t)	__libc_cond_timedwait((c), (m), (t))
 #define	cond_destroy(c)		__libc_cond_destroy((c))

 __BEGIN_DECLS
 int	__libc_rwlock_init(rwlock_t *, const rwlockattr_t *);
 int	__libc_rwlock_rdlock(rwlock_t *);
 int	__libc_rwlock_wrlock(rwlock_t *);
 int	__libc_rwlock_tryrdlock(rwlock_t *);
 int	__libc_rwlock_trywrlock(rwlock_t *);
 int	__libc_rwlock_unlock(rwlock_t *);
 int	__libc_rwlock_destroy(rwlock_t *);
 __END_DECLS

 #define	rwlock_init(l, a)	__libc_rwlock_init((l), (a))
 #define	rwlock_rdlock(l)	__libc_rwlock_rdlock((l))
 #define	rwlock_wrlock(l)	__libc_rwlock_wrlock((l))
 #define	rwlock_tryrdlock(l)	__libc_rwlock_tryrdlock((l))
 #define	rwlock_trywrlock(l)	__libc_rwlock_trywrlock((l))
 #define	rwlock_unlock(l)	__libc_rwlock_unlock((l))
 #define	rwlock_destroy(l)	__libc_rwlock_destroy((l))

 __BEGIN_DECLS
 int	__libc_thr_keycreate(thread_key_t *, void (*)(void *));
 int	__libc_thr_setspecific(thread_key_t, const void *);
 void	*__libc_thr_getspecific(thread_key_t);
 int	__libc_thr_keydelete(thread_key_t);
 __END_DECLS

 #define	thr_keycreate(k, d)	__libc_thr_keycreate((k), (d))
 #define	thr_setspecific(k, p)	__libc_thr_setspecific((k), (p))
 #define	thr_getspecific(k)	__libc_thr_getspecific((k))
 #define	thr_keydelete(k)	__libc_thr_keydelete((k))

 __BEGIN_DECLS
 int	__libc_thr_once(once_t *, void (*)(void));
 int	__libc_thr_sigsetmask(int, const sigset_t *, sigset_t *);
 thr_t	__libc_thr_self(void);
 int	__libc_thr_yield(void);
 void	__libc_thr_create(thr_t *, const thrattr_t *,
 	    void *(*)(void *), void *);
 void	__libc_thr_exit(void *) __attribute__((__noreturn__));
 int	*__libc_thr_errno(void);
 int	__libc_thr_setcancelstate(int, int *);

 extern int __isthreaded;
 __END_DECLS

 #define	thr_once(o, f)		__libc_thr_once((o), (f))
 #define	thr_sigsetmask(f, n, o)	__libc_thr_sigsetmask((f), (n), (o))
 #define	thr_self()		__libc_thr_self()
 #define	thr_yield()		__libc_thr_yield()
 #define	thr_create(tp, ta, f, a) __libc_thr_create((tp), (ta), (f), (a))
 #define	thr_exit(v)		__libc_thr_exit((v))
 #define	thr_errno()		__libc_thr_errno()
 #define	thr_enabled()		(__isthreaded)
 #define thr_setcancelstate(n, o) __libc_thr_setcancelstate((n),(o))
 #endif /* __LIBC_THREAD_STUBS */

 #define	FLOCKFILE(fp)		__flockfile_internal(fp, 1)
 #define	FUNLOCKFILE(fp)		__funlockfile_internal(fp, 1)

 #else /* _REENTRANT */

 #define	mutex_init(m, a)
 #define	mutex_lock(m)
 #define	mutex_trylock(m)
 #define	mutex_unlock(m)
 #define	mutex_destroy(m)

 #define	cond_init(c, t, a)
 #define	cond_signal(c)
 #define	cond_broadcast(c)
 #define	cond_wait(c, m)
 #define	cond_timedwait(c, m, t)
 #define	cond_destroy(c)

 #define	rwlock_init(l, a)
 #define	rwlock_rdlock(l)
 #define	rwlock_wrlock(l)
 #define	rwlock_tryrdlock(l)
 #define	rwlock_trywrlock(l)
 #define	rwlock_unlock(l)
 #define	rwlock_destroy(l)

 #define	thr_keycreate(k, d)
 #define	thr_setspecific(k, p)
 #define	thr_getspecific(k)
 #define	thr_keydelete(k)

 #define	thr_once(o, f)
 #define	thr_sigsetmask(f, n, o)
 #define	thr_self()
 #define	thr_errno()

 #define	FLOCKFILE(fp)
 #define	FUNLOCKFILE(fp)

 #endif /* _REENTRANT */
	/* $NetBSD: reentrant.h,v 1.10 2004/12/14 00:23:19 nathanw Exp $ */

	/*-
	* Copyright (c) 1997, 1998, 2003 The NetBSD Foundation, Inc.
	* All rights reserved.
	*
	* This code is derived from software contributed to The NetBSD Foundation
	* by J.T. Conklin, by Nathan J. Williams, and by Jason R. Thorpe.
	*
	* 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 NetBSD
	* Foundation, Inc. and its contributors.
	* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
	*/

	/*
	* Requirements:
	*
	* 1. The thread safe mechanism should be lightweight so the library can
	* be used by non-threaded applications without unreasonable overhead.
	*
	* 2. There should be no dependency on a thread engine for non-threaded
	* applications.
	*
	* 3. There should be no dependency on any particular thread engine.
	*
	* 4. The library should be able to be compiled without support for thread
	* safety.
	*
	*
	* Rationale:
	*
	* One approach for thread safety is to provide discrete versions of the
	* library: one thread safe, the other not. The disadvantage of this is
	* that libc is rather large, and two copies of a library which are 99%+
	* identical is not an efficent use of resources.
	*
	* Another approach is to provide a single thread safe library. However,
	* it should not add significant run time or code size overhead to non-
	* threaded applications.
	*
	* Since the NetBSD C library is used in other projects, it should be
	* easy to replace the mutual exclusion primitives with ones provided by
	* another system. Similarly, it should also be easy to remove all
	* support for thread safety completely if the target environment does
	* not support threads.
	*
	*
	* Implementation Details:
	*
	* The thread primitives used by the library (mutex_t, mutex_lock, etc.)
	* are macros which expand to the cooresponding primitives provided by
	* the thread engine or to nothing. The latter is used so that code is
	* not unreasonably cluttered with #ifdefs when all thread safe support
	* is removed.
	*
	* The thread macros can be directly mapped to the mutex primitives from
	* pthreads, however it should be reasonably easy to wrap another mutex
	* implementation so it presents a similar interface.
	*
	* The thread functions operate by dispatching to symbols which are, by
	* default, weak-aliased to no-op functions in thread-stub/thread-stub.c
	* (some uses of thread operations are conditional on __isthreaded, but
	* not all of them are).
	*
	* When the thread library is linked in, it provides strong-alias versions
	* of those symbols which dispatch to its own real thread operations.
	*
	*/

	#ifdef _REENTRANT

	/*
	* Abtract thread interface for thread-safe libraries. These routines
	* will use stubs in libc if the application is not linked against the
	* pthread library, and the real function in the pthread library if it
	* is.
	*/

	#include <pthread.h>
	#include <signal.h>
	#include <sys/cdefs.h>

	#define mutex_t pthread_mutex_t
	#define MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER

	#define mutexattr_t pthread_mutexattr_t

	#define MUTEX_TYPE_NORMAL PTHREAD_MUTEX_NORMAL
	#define MUTEX_TYPE_ERRORCHECK PTHREAD_MUTEX_ERRORCHECK
	#define MUTEX_TYPE_RECURSIVE PTHREAD_MUTEX_RECURSIVE

	#define cond_t pthread_cond_t
	#define COND_INITIALIZER PTHREAD_COND_INITIALIZER

	#define condattr_t pthread_condattr_t

	#define rwlock_t pthread_rwlock_t
	#define RWLOCK_INITIALIZER PTHREAD_RWLOCK_INITIALIZER

	#define rwlockattr_t pthread_rwlockattr_t

	#define thread_key_t pthread_key_t

	#define thr_t pthread_t

	#define thrattr_t pthread_attr_t

	#define once_t pthread_once_t
	#define ONCE_INITIALIZER PTHREAD_ONCE_INIT

	#ifndef __LIBC_THREAD_STUBS

	__BEGIN_DECLS
	int __libc_mutex_init(mutex_t , const mutexattr_t );
	int __libc_mutex_lock(mutex_t *);
	int __libc_mutex_trylock(mutex_t *);
	int __libc_mutex_unlock(mutex_t *);
	int __libc_mutex_destroy(mutex_t *);

	int __libc_mutexattr_init(mutexattr_t *);
	int __libc_mutexattr_settype(mutexattr_t *, int);
	int __libc_mutexattr_destroy(mutexattr_t *);
	__END_DECLS

	#define mutex_init(m, a) __libc_mutex_init((m), (a))
	#define mutex_lock(m) __libc_mutex_lock((m))
	#define mutex_trylock(m) __libc_mutex_trylock((m))
	#define mutex_unlock(m) __libc_mutex_unlock((m))
	#define mutex_destroy(m) __libc_mutex_destroy((m))

	#define mutexattr_init(ma) __libc_mutexattr_init((ma))
	#define mutexattr_settype(ma, t) __libc_mutexattr_settype((ma), (t))
	#define mutexattr_destroy(ma) __libc_mutexattr_destroy((ma))

	__BEGIN_DECLS
	int __libc_cond_init(cond_t , const condattr_t );
	int __libc_cond_signal(cond_t *);
	int __libc_cond_broadcast(cond_t *);
	int __libc_cond_wait(cond_t , mutex_t );
	int __libc_cond_timedwait(cond_t , mutex_t , const struct timespec *);
	int __libc_cond_destroy(cond_t *);
	__END_DECLS

	#define cond_init(c, t, a) __libc_cond_init((c), (a))
	#define cond_signal(c) __libc_cond_signal((c))
	#define cond_broadcast(c) __libc_cond_broadcast((c))
	#define cond_wait(c, m) __libc_cond_wait((c), (m))
	#define cond_timedwait(c, m, t) __libc_cond_timedwait((c), (m), (t))
	#define cond_destroy(c) __libc_cond_destroy((c))

	__BEGIN_DECLS
	int __libc_rwlock_init(rwlock_t , const rwlockattr_t );
	int __libc_rwlock_rdlock(rwlock_t *);
	int __libc_rwlock_wrlock(rwlock_t *);
	int __libc_rwlock_tryrdlock(rwlock_t *);
	int __libc_rwlock_trywrlock(rwlock_t *);
	int __libc_rwlock_unlock(rwlock_t *);
	int __libc_rwlock_destroy(rwlock_t *);
	__END_DECLS

	#define rwlock_init(l, a) __libc_rwlock_init((l), (a))
	#define rwlock_rdlock(l) __libc_rwlock_rdlock((l))
	#define rwlock_wrlock(l) __libc_rwlock_wrlock((l))
	#define rwlock_tryrdlock(l) __libc_rwlock_tryrdlock((l))
	#define rwlock_trywrlock(l) __libc_rwlock_trywrlock((l))
	#define rwlock_unlock(l) __libc_rwlock_unlock((l))
	#define rwlock_destroy(l) __libc_rwlock_destroy((l))

	__BEGIN_DECLS
	int __libc_thr_keycreate(thread_key_t , void ()(void *));
	int __libc_thr_setspecific(thread_key_t, const void *);
	void *__libc_thr_getspecific(thread_key_t);
	int __libc_thr_keydelete(thread_key_t);
	__END_DECLS

	#define thr_keycreate(k, d) __libc_thr_keycreate((k), (d))
	#define thr_setspecific(k, p) __libc_thr_setspecific((k), (p))
	#define thr_getspecific(k) __libc_thr_getspecific((k))
	#define thr_keydelete(k) __libc_thr_keydelete((k))

	__BEGIN_DECLS
	int __libc_thr_once(once_t , void ()(void));
	int __libc_thr_sigsetmask(int, const sigset_t , sigset_t );
	thr_t __libc_thr_self(void);
	int __libc_thr_yield(void);
	void __libc_thr_create(thr_t , const thrattr_t ,
	void ()(void ), void );
	void __libc_thr_exit(void *) __attribute__((__noreturn__));
	int *__libc_thr_errno(void);
	int __libc_thr_setcancelstate(int, int *);

	extern int __isthreaded;
	__END_DECLS

	#define thr_once(o, f) __libc_thr_once((o), (f))
	#define thr_sigsetmask(f, n, o) __libc_thr_sigsetmask((f), (n), (o))
	#define thr_self() __libc_thr_self()
	#define thr_yield() __libc_thr_yield()
	#define thr_create(tp, ta, f, a) __libc_thr_create((tp), (ta), (f), (a))
	#define thr_exit(v) __libc_thr_exit((v))
	#define thr_errno() __libc_thr_errno()
	#define thr_enabled() (__isthreaded)
	#define thr_setcancelstate(n, o) __libc_thr_setcancelstate((n),(o))
	#endif /* __LIBC_THREAD_STUBS */

	#define FLOCKFILE(fp) __flockfile_internal(fp, 1)
	#define FUNLOCKFILE(fp) __funlockfile_internal(fp, 1)

	#else /* _REENTRANT */

	#define mutex_init(m, a)
	#define mutex_lock(m)
	#define mutex_trylock(m)
	#define mutex_unlock(m)
	#define mutex_destroy(m)

	#define cond_init(c, t, a)
	#define cond_signal(c)
	#define cond_broadcast(c)
	#define cond_wait(c, m)
	#define cond_timedwait(c, m, t)
	#define cond_destroy(c)

	#define rwlock_init(l, a)
	#define rwlock_rdlock(l)
	#define rwlock_wrlock(l)
	#define rwlock_tryrdlock(l)
	#define rwlock_trywrlock(l)
	#define rwlock_unlock(l)
	#define rwlock_destroy(l)

	#define thr_keycreate(k, d)
	#define thr_setspecific(k, p)
	#define thr_getspecific(k)
	#define thr_keydelete(k)

	#define thr_once(o, f)
	#define thr_sigsetmask(f, n, o)
	#define thr_self()
	#define thr_errno()

	#define FLOCKFILE(fp)
	#define FUNLOCKFILE(fp)

	#endif /* _REENTRANT */