[apple/xnu.git] / libsyscall / wrappers / select-base.c

/*
 * Copyright (c) 2005, 2007 Apple Inc. All rights reserved.
 *
 * @APPLE_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. 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_LICENSE_HEADER_END@
 */

#if defined(__LP64__) && (defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050))
#undef __DARWIN_NON_CANCELABLE
#define __DARWIN_NON_CANCELABLE 0
#endif /* __LP64__ && (VARIANT_CANCELABLE || VARIANT_PRE1050) */

#if defined(VARIANT_DARWIN_EXTSN)
#define _DARWIN_C_SOURCE
#define _DARWIN_UNLIMITED_SELECT
#endif

#include <sys/select.h>
#include <sys/time.h>
#include <sys/signal.h>
#include "_errno.h"

#if defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050)
#if !defined(VARIANT_DARWIN_EXTSN)
extern int __select(int, fd_set * __restrict, fd_set * __restrict,
	fd_set * __restrict, struct timeval * __restrict);
#endif
int __pselect(int, fd_set * __restrict, fd_set * __restrict,
	fd_set * __restrict, const struct timespec * __restrict, const sigset_t * __restrict);
#else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
#if !defined(VARIANT_DARWIN_EXTSN)
int __select_nocancel(int, fd_set * __restrict, fd_set * __restrict,
	fd_set * __restrict, struct timeval * __restrict);
#endif
int __pselect_nocancel(int, fd_set * __restrict, fd_set * __restrict,
	fd_set * __restrict, const struct timespec * __restrict, const sigset_t * __restrict);
#endif /* VARIANT_CANCELABLE || VARIANT_PRE1050 */

#if !defined(VARIANT_DARWIN_EXTSN)
/*
 * select() implementation for 1050 and legacy (cancelable and non-cancelable)
 * variants. The darwin extension variants (both cancelable & non-cancelable) are
 * mapped directly to the syscall stub.
 */
int
select(int nfds, fd_set * __restrict readfds, fd_set * __restrict writefds,
	fd_set * __restrict exceptfds, struct timeval * __restrict
#if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
	intimeout
#else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
	timeout
#endif /* VARIANT_LEGACY || VARIANT_PRE1050 */
	)
{
#if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
	struct timeval tb, *timeout;

	/*
	 * Legacy select behavior is minimum 10 msec when tv_usec is non-zero
	 */
	if (intimeout && intimeout->tv_sec == 0 && intimeout->tv_usec > 0 && intimeout->tv_usec < 10000) {
		tb.tv_sec = 0;
		tb.tv_usec = 10000;
		timeout = &tb;
	} else {
		timeout = intimeout;
	}
#else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
	if (nfds > FD_SETSIZE) {
		errno = EINVAL;
		return -1;
	}
#endif

#if defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050)
	return __select(nfds, readfds, writefds, exceptfds, timeout);
#else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
	return __select_nocancel(nfds, readfds, writefds, exceptfds, timeout);
#endif /* VARIANT_CANCELABLE || VARIANT_PRE1050 */
}
#endif /* !defined(VARIANT_DARWIN_EXTSN) */


/*
 * User-space emulation of pselect() syscall for B&I
 * TODO: remove when B&I move to xnu with native pselect()
 */
extern int __pthread_sigmask(int, const sigset_t *, sigset_t *);
static int
_pselect_emulated(int count, fd_set * __restrict rfds, fd_set * __restrict wfds,
		fd_set * __restrict efds, const struct timespec * __restrict timo,
		const sigset_t * __restrict mask)
{
	sigset_t omask;
	struct timeval tvtimo, *tvp;
	int rv, sverrno;

	if (timo) {
		tvtimo.tv_sec = timo->tv_sec;
		tvtimo.tv_usec = (__darwin_suseconds_t)(timo->tv_nsec / 1000);
		tvp = &tvtimo;
	} else {
		tvp = 0;
	}

	if (mask != 0) {
		rv = __pthread_sigmask(SIG_SETMASK, mask, &omask);
		if (rv != 0)
			return rv;
	}

	rv = select(count, rfds, wfds, efds, tvp);
	if (mask != 0) {
		sverrno = errno;
		__pthread_sigmask(SIG_SETMASK, &omask, (sigset_t *)0);
		errno = sverrno;
	}

	return rv;
}

/*
 * pselect() implementation for all variants. Unlike select(), we implement the
 * darwin extension variants here to catch cases where xnu doesn't implement
 * pselect and we need to emulate.
 */
int
pselect(int nfds, fd_set * __restrict readfds, fd_set * __restrict writefds,
	fd_set * __restrict exceptfds, const struct timespec * __restrict
#if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
	intimeout,
#else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
	timeout,
#endif /* VARIANT_LEGACY || VARIANT_PRE1050 */
	const sigset_t * __restrict sigmask)
{
	int ret;
#if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
	struct timespec tb;
	const struct timespec *timeout;

	/*
	 * Legacy select behavior is minimum 10 msec when tv_usec is non-zero
	 */
	if (intimeout && intimeout->tv_sec == 0 && intimeout->tv_nsec > 0 && intimeout->tv_nsec < 10000000L) {
		tb.tv_sec = 0;
		tb.tv_nsec = 10000000L;
		timeout = &tb;
	} else {
		timeout = intimeout;
	}
#elif defined(VARIANT_DARWIN_EXTSN)
#else
	/* 1050 variant */
	if (nfds > FD_SETSIZE) {
		errno = EINVAL;
		return -1;
	}
#endif

#if defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050)
	ret = __pselect(nfds, readfds, writefds, exceptfds, timeout, sigmask);
#else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
	ret = __pselect_nocancel(nfds, readfds, writefds, exceptfds, timeout, sigmask);
#endif /* VARIANT_CANCELABLE || VARIANT_PRE1050 */

	if (ret == -1 && errno == ENOSYS) {
		ret = _pselect_emulated(nfds, readfds, writefds, exceptfds, timeout, sigmask);
	}

	return ret;
}
Commit	Line	Data
6d2010ae A	1	/*
	2	* Copyright (c) 2005, 2007 Apple Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	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. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
	12	*
	13	* The Original Code and all software distributed under the License are
	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
	23
	24	#if defined(__LP64__) && (defined(VARIANT_CANCELABLE) \|\| defined(VARIANT_PRE1050))
	25	#undef __DARWIN_NON_CANCELABLE
	26	#define __DARWIN_NON_CANCELABLE 0
	27	#endif /* __LP64__ && (VARIANT_CANCELABLE \|\| VARIANT_PRE1050) */
	28
4bd07ac2 A	29	#if defined(VARIANT_DARWIN_EXTSN)
	30	#define _DARWIN_C_SOURCE
	31	#define _DARWIN_UNLIMITED_SELECT
	32	#endif
	33
6d2010ae	34	#include <sys/select.h>
4bd07ac2 A	35	#include <sys/time.h>
4bd07ac2 A	36	#include <sys/signal.h>
6d2010ae A	37	#include "_errno.h"
	38
	39	#if defined(VARIANT_CANCELABLE) \|\| defined(VARIANT_PRE1050)
4bd07ac2	40	#if !defined(VARIANT_DARWIN_EXTSN)
6d2010ae A	41	extern int __select(int, fd_set * __restrict, fd_set * __restrict,
6d2010ae A	42	fd_set * __restrict, struct timeval * __restrict);
4bd07ac2 A	43	#endif
	44	int __pselect(int, fd_set * __restrict, fd_set * __restrict,
	45	fd_set * __restrict, const struct timespec * __restrict, const sigset_t * __restrict);
6d2010ae	46	#else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
4bd07ac2	47	#if !defined(VARIANT_DARWIN_EXTSN)
6d2010ae A	48	int __select_nocancel(int, fd_set * __restrict, fd_set * __restrict,
6d2010ae A	49	fd_set * __restrict, struct timeval * __restrict);
4bd07ac2 A	50	#endif
	51	int __pselect_nocancel(int, fd_set * __restrict, fd_set * __restrict,
	52	fd_set * __restrict, const struct timespec * __restrict, const sigset_t * __restrict);
6d2010ae A	53	#endif /* VARIANT_CANCELABLE \|\| VARIANT_PRE1050 */
6d2010ae A	54
4bd07ac2	55	#if !defined(VARIANT_DARWIN_EXTSN)
6d2010ae	56	/*
4bd07ac2 A	57	* select() implementation for 1050 and legacy (cancelable and non-cancelable)
	58	* variants. The darwin extension variants (both cancelable & non-cancelable) are
	59	* mapped directly to the syscall stub.
6d2010ae A	60	*/
	61	int
	62	select(int nfds, fd_set * __restrict readfds, fd_set * __restrict writefds,
	63	fd_set * __restrict exceptfds, struct timeval * __restrict
	64	#if defined(VARIANT_LEGACY) \|\| defined(VARIANT_PRE1050)
	65	intimeout
	66	#else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
	67	timeout
	68	#endif /* VARIANT_LEGACY \|\| VARIANT_PRE1050 */
	69	)
	70	{
6d2010ae A	71	#if defined(VARIANT_LEGACY) \|\| defined(VARIANT_PRE1050)
	72	struct timeval tb, *timeout;
	73
	74	/*
	75	* Legacy select behavior is minimum 10 msec when tv_usec is non-zero
	76	*/
	77	if (intimeout && intimeout->tv_sec == 0 && intimeout->tv_usec > 0 && intimeout->tv_usec < 10000) {
	78	tb.tv_sec = 0;
	79	tb.tv_usec = 10000;
	80	timeout = &tb;
4bd07ac2	81	} else {
6d2010ae	82	timeout = intimeout;
4bd07ac2	83	}
6d2010ae A	84	#else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
	85	if (nfds > FD_SETSIZE) {
	86	errno = EINVAL;
	87	return -1;
	88	}
4bd07ac2 A	89	#endif
4bd07ac2 A	90
6d2010ae A	91	#if defined(VARIANT_CANCELABLE) \|\| defined(VARIANT_PRE1050)
	92	return __select(nfds, readfds, writefds, exceptfds, timeout);
	93	#else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
	94	return __select_nocancel(nfds, readfds, writefds, exceptfds, timeout);
	95	#endif /* VARIANT_CANCELABLE \|\| VARIANT_PRE1050 */
	96	}
4bd07ac2 A	97	#endif /* !defined(VARIANT_DARWIN_EXTSN) */
	98
	99
	100	/*
	101	* User-space emulation of pselect() syscall for B&I
	102	* TODO: remove when B&I move to xnu with native pselect()
	103	*/
	104	extern int __pthread_sigmask(int, const sigset_t , sigset_t );
	105	static int
	106	_pselect_emulated(int count, fd_set * __restrict rfds, fd_set * __restrict wfds,
	107	fd_set * __restrict efds, const struct timespec * __restrict timo,
	108	const sigset_t * __restrict mask)
	109	{
	110	sigset_t omask;
	111	struct timeval tvtimo, *tvp;
	112	int rv, sverrno;
	113
	114	if (timo) {
	115	tvtimo.tv_sec = timo->tv_sec;
	116	tvtimo.tv_usec = (__darwin_suseconds_t)(timo->tv_nsec / 1000);
	117	tvp = &tvtimo;
	118	} else {
	119	tvp = 0;
	120	}
	121
	122	if (mask != 0) {
	123	rv = __pthread_sigmask(SIG_SETMASK, mask, &omask);
	124	if (rv != 0)
	125	return rv;
	126	}
	127
	128	rv = select(count, rfds, wfds, efds, tvp);
	129	if (mask != 0) {
	130	sverrno = errno;
	131	__pthread_sigmask(SIG_SETMASK, &omask, (sigset_t *)0);
	132	errno = sverrno;
	133	}
	134
	135	return rv;
	136	}
	137
	138	/*
	139	* pselect() implementation for all variants. Unlike select(), we implement the
	140	* darwin extension variants here to catch cases where xnu doesn't implement
	141	* pselect and we need to emulate.
	142	*/
	143	int
	144	pselect(int nfds, fd_set * __restrict readfds, fd_set * __restrict writefds,
	145	fd_set * __restrict exceptfds, const struct timespec * __restrict
	146	#if defined(VARIANT_LEGACY) \|\| defined(VARIANT_PRE1050)
	147	intimeout,
	148	#else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
	149	timeout,
	150	#endif /* VARIANT_LEGACY \|\| VARIANT_PRE1050 */
	151	const sigset_t * __restrict sigmask)
	152	{
	153	int ret;
	154	#if defined(VARIANT_LEGACY) \|\| defined(VARIANT_PRE1050)
	155	struct timespec tb;
	156	const struct timespec *timeout;
	157
	158	/*
	159	* Legacy select behavior is minimum 10 msec when tv_usec is non-zero
	160	*/
161	if (intimeout && intimeout->tv_sec == 0 && intimeout->tv_nsec > 0 && intimeout->tv_nsec < 10000000L) {
162	tb.tv_sec = 0;
163	tb.tv_nsec = 10000000L;
164	timeout = &tb;
165	} else {
166	timeout = intimeout;
167	}
168	#elif defined(VARIANT_DARWIN_EXTSN)
169	#else
170	/* 1050 variant */
171	if (nfds > FD_SETSIZE) {
172	errno = EINVAL;
173	return -1;
174	}
175	#endif
176
177	#if defined(VARIANT_CANCELABLE) \|\| defined(VARIANT_PRE1050)
178	ret = __pselect(nfds, readfds, writefds, exceptfds, timeout, sigmask);
179	#else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
180	ret = __pselect_nocancel(nfds, readfds, writefds, exceptfds, timeout, sigmask);
181	#endif /* VARIANT_CANCELABLE \|\| VARIANT_PRE1050 */
182
183	if (ret == -1 && errno == ENOSYS) {
184	ret = _pselect_emulated(nfds, readfds, writefds, exceptfds, timeout, sigmask);
185	}
186
187	return ret;
188	}