Make wait6(2), waitid(3) and ppoll(2) cancellation points. The

waitid() function is required to be cancellable by the standard.  The
wait6() and ppoll() follow the other syscalls in their groups.

Reviewed by:	jhb, jilles (previous versions)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
This commit is contained in:
Konstantin Belousov 2015-04-18 21:35:41 +00:00
parent 9dda94167d
commit 3d0045bb2b
8 changed files with 164 additions and 2 deletions

View File

@ -37,6 +37,7 @@ __FBSDID("$FreeBSD$");
#include <signal.h>
#include <errno.h>
#include "un-namespace.h"
#include "libc_private.h"
int
__waitid(idtype_t idtype, id_t id, siginfo_t *info, int flags)
@ -44,7 +45,9 @@ __waitid(idtype_t idtype, id_t id, siginfo_t *info, int flags)
int status;
pid_t ret;
ret = _wait6(idtype, id, &status, flags, NULL, info);
ret = ((pid_t (*)(idtype_t, id_t, int *, int, struct __wrusage *,
siginfo_t *))__libc_interposing[INTERPOS_wait6])(idtype, id,
&status, flags, NULL, info);
/*
* According to SUSv4, waitid() shall not return a PID when a

View File

@ -222,6 +222,8 @@ enum {
INTERPOS_spinlock,
INTERPOS_spinunlock,
INTERPOS_kevent,
INTERPOS_wait6,
INTERPOS_ppoll,
INTERPOS_MAX
};
@ -305,6 +307,8 @@ struct timeval;
struct timezone;
struct __siginfo;
struct __ucontext;
struct __wrusage;
enum idtype;
int __sys_aio_suspend(const struct aiocb * const[], int,
const struct timespec *);
int __sys_accept(int, struct sockaddr *, __socklen_t *);
@ -329,6 +333,8 @@ int __sys_pselect(int, struct fd_set *, struct fd_set *,
struct fd_set *, const struct timespec *,
const __sigset_t *);
int __sys_poll(struct pollfd *, unsigned, int);
int __sys_ppoll(struct pollfd *, unsigned, const struct timespec *,
const __sigset_t *);
__ssize_t __sys_pread(int, void *, __size_t, __off_t);
__ssize_t __sys_pwrite(int, const void *, __size_t, __off_t);
__ssize_t __sys_read(int, void *, __size_t);
@ -357,6 +363,8 @@ int __sys_thr_kill(long, int);
int __sys_thr_self(long *);
int __sys_truncate(const char *, __off_t);
__pid_t __sys_wait4(__pid_t, int *, int, struct rusage *);
__pid_t __sys_wait6(enum idtype, __id_t, int *, int,
struct __wrusage *, struct __siginfo *);
__ssize_t __sys_write(int, const void *, __size_t);
__ssize_t __sys_writev(int, const struct iovec *, int);

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@ -57,6 +57,7 @@ INTERPOSED = \
open \
openat \
poll \
ppoll \
pselect \
read \
readv \
@ -73,6 +74,7 @@ INTERPOSED = \
sigwaitinfo \
swapcontext \
wait4 \
wait6 \
write \
writev

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@ -76,6 +76,8 @@ interpos_func_t __libc_interposing[INTERPOS_MAX] = {
SLOT(spinlock, __libc_spinlock_stub),
SLOT(spinunlock, __libc_spinunlock_stub),
SLOT(kevent, __sys_kevent),
SLOT(wait6, __sys_wait6),
SLOT(ppoll, __sys_ppoll),
};
#undef SLOT

51
lib/libc/sys/ppoll.c Normal file
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@ -0,0 +1,51 @@
/*
* Copyright (c) 2015 The FreeBSD Foundation.
* All rights reserved.
*
* Portions of this software were developed by Konstantin Belousov
* under sponsorship from the FreeBSD Foundation.
*
* 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(s), this list of conditions and the following disclaimer as
* the first lines of this file unmodified other than the possible
* addition of one or more copyright notices.
* 2. Redistributions in binary form must reproduce the above copyright
* notice(s), this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/poll.h>
#include "libc_private.h"
__weak_reference(__sys_ppoll, __ppoll);
#pragma weak ppoll
int
ppoll(struct pollfd pfd[], nfds_t nfds, const struct timespec *__restrict
timeout, const sigset_t *__restrict newsigmask)
{
return (((int (*)(struct pollfd *, nfds_t, const struct timespec *,
const sigset_t *)) __libc_interposing[INTERPOS_ppoll])(pfd, nfds,
timeout, newsigmask));
}

52
lib/libc/sys/wait6.c Normal file
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@ -0,0 +1,52 @@
/*
* Copyright (c) 2015 The FreeBSD Foundation.
* All rights reserved.
*
* Portions of this software were developed by Konstantin Belousov
* under sponsorship from the FreeBSD Foundation.
*
* 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(s), this list of conditions and the following disclaimer as
* the first lines of this file unmodified other than the possible
* addition of one or more copyright notices.
* 2. Redistributions in binary form must reproduce the above copyright
* notice(s), this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``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 COPYRIGHT HOLDER(S) 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include "libc_private.h"
__weak_reference(__sys_wait6, __wait6);
#pragma weak wait6
pid_t
wait6(idtype_t idtype, id_t id, int *status, int options, struct __wrusage *ru,
siginfo_t *infop)
{
return (((pid_t (*)(idtype_t, id_t, int *, int, struct __wrusage *,
siginfo_t *))__libc_interposing[INTERPOS_wait6])(idtype, id,
status, options, ru, infop));
}

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@ -321,6 +321,26 @@ __thr_poll(struct pollfd *fds, unsigned int nfds, int timeout)
return (ret);
}
/*
* Cancellation behavior:
* Thread may be canceled at start, but if the system call returns something,
* the thread is not canceled.
*/
static int
__thr_ppoll(struct pollfd pfd[], nfds_t nfds, const struct timespec *
timeout, const sigset_t *newsigmask)
{
struct pthread *curthread;
int ret;
curthread = _get_curthread();
_thr_cancel_enter(curthread);
ret = __sys_ppoll(pfd, nfds, timeout, newsigmask);
_thr_cancel_leave(curthread, ret == -1);
return (ret);
}
/*
* Cancellation behavior:
* Thread may be canceled at start, but if the system call returns something,
@ -543,6 +563,25 @@ __thr_wait4(pid_t pid, int *status, int options, struct rusage *rusage)
return (ret);
}
/*
* Cancellation behavior:
* Thread may be canceled at start, but if the system call returns
* a child pid, the thread is not canceled.
*/
static pid_t
__thr_wait6(idtype_t idtype, id_t id, int *status, int options,
struct __wrusage *ru, siginfo_t *infop)
{
struct pthread *curthread;
pid_t ret;
curthread = _get_curthread();
_thr_cancel_enter(curthread);
ret = __sys_wait6(idtype, id, status, options, ru, infop);
_thr_cancel_leave(curthread, ret <= 0);
return (ret);
}
/*
* Cancellation behavior:
* Thread may be canceled at start, but if the thread wrote some data,
@ -623,6 +662,8 @@ __thr_interpose_libc(void)
SLOT(spinlock);
SLOT(spinunlock);
SLOT(kevent);
SLOT(wait6);
SLOT(ppoll);
#undef SLOT
*(__libc_interposing_slot(
INTERPOS__pthread_mutex_init_calloc_cb)) =

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@ -1,5 +1,5 @@
.\" $FreeBSD$
.Dd March 29, 2015
.Dd April 16, 2015
.Dt PTHREAD_TESTCANCEL 3
.Os
.Sh NAME
@ -132,6 +132,7 @@ argument is non-zero.
.It Fn openat
.It Fn pause
.It Fn poll
.It Fn ppoll
.It Fn pselect
.It Fn pthread_cond_timedwait
.It Fn pthread_cond_wait
@ -159,6 +160,8 @@ argument is non-zero.
.It Fn wait
.It Fn wait3
.It Fn wait4
.It Fn wait6
.It Fn waitid
.It Fn waitpid
.It Fn write
.It Fn writev