glibc/nptl/pthread_cancel.c
Adhemerval Zanella fa872e1b62 Clean pthread functions namespaces for C11 threads
This patch adds internal definition (through {libc_}hidden_{proto,def}) and
also change some strong to weak alias for symbols that might be used by C11
threads implementations.

The patchset should not change libc/libpthread functional, although object
changes are expected (since now internal symbols are used instead) and final
exported symbols through GLIBC_PRIVATE is also expanded (to cover libpthread
usage of __mmap{64}, __munmap, __mprotect).

Checked with a build for all major ABI (aarch64-linux-gnu, alpha-linux-gnu,
arm-linux-gnueabi, i386-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu [1], mips{64}-linux-gnu, nios2-linux-gnu,
powerpc{64le}-linux-gnu, s390{x}-linux-gnu, sparc{64}-linux-gnu,
tile{pro,gx}-linux-gnu, and x86_64-linux-gnu).

	* include/sched.h (__sched_get_priority_max): Add libc hidden proto.
	(__sched_get_prioriry_min): Likewise.
	* include/sys/mman.h (__mmap): Likewise.
	(__mmap64): Likewise.
	(__munmap): Likewise.
	(__mprotect): Likewise.
	* include/termios.h (__tcsetattr): Likewise.
	* include/time.h (__nanosleep): Use hidden_proto instead of
	libc_hidden_proto.
	* posix/nanosleep.c (__nanosleep): Likewise.
	* misc/Versions (libc): Export __mmap, __munmap, __mprotect,
	__sched_get_priority_min, and __sched_get_priority_max under
	GLIBC_PRIVATE.
	* nptl/allocatestack.c (__free_stacks): Use internal definition for
	libc symbols.
	(change_stack_perm): Likewise.
	(allocate_stack): Likewise.
	* sysdeps/posix/gethostname.c: Likewise.
	* nptl/tpp.c (__init_sched_fifo_prio): Likewise.
	* sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system): Likewise.
	* sysdeps/unix/sysv/linux/powerpc/ioctl.c (__ioctl): Likewise.
	* nptl/pthreadP.h (__pthread_mutex_timedlock): Add definition.
	(__pthread_key_delete): Likewise.
	(__pthread_detach): Likewise.
	(__pthread_cancel): Likewise.
	(__pthread_mutex_trylock): Likewise.
	(__pthread_mutexattr_init): Likewise.
	(__pthread_mutexattr_settype): Likewise.
	* nptl/pthread_cancel.c (pthread_cancel): Change to internal name and
	create alias for exported one.
	* nptl/pthread_join.c (pthread_join): Likewise.
	* nptl/pthread_detach.c (pthread_detach): Likewise.
	* nptl/pthread_key_delete.c (pthread_key_delete): Likewise.
	* nptl/pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise.
	* nptl/pthread_create.c: Change static requirements for pthread
	symbols.
	* nptl/pthread_equal.c (__pthread_equal): Change strong alias to weak
	for internal definition.
	* nptl/pthread_exit.c (__pthread_exit): Likewise.
	* nptl/pthread_getspecific.c (__pthread_getspecific): Likewise.
	* nptl/pthread_key_create.c (__pthread_key_create): Likewise.
	* nptl/pthread_mutex_destroy.c (__pthread_mutex_destroy): Likewise.
	* nptl/pthread_mutex_init.c (__pthread_mutex_init): Likewise.
	* nptl/pthread_mutex_lock.c (__pthread_mutex_lock): Likewise.
	* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock): Likewise.
	* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock): Likewise.
	* nptl/pthread_mutexattr_init.c (__pthread_mutexattr_init): Likwise.
	* nptl/pthread_mutexattr_settype.c (__pthread_mutexattr_settype):
	Likewise.
	* nptl/pthread_self.c (__pthread_self): Likewise.
	* nptl/pthread_setspecific.c (__pthread_setspecific): Likewise.
	* sysdeps/unix/sysv/linux/tcsetattr.c (tcsetattr): Likewise.
	* misc/mmap.c (__mmap): Add internal symbol definition.
	* misc/mmap.c (__mmap64): Likewise.
	* sysdeps/unix/sysv/linux/mmap.c (__mmap): Likewise.
	* sysdeps/unix/sysv/linux/mmap64.c (__mmap): Likewise.
	(__mmap64): Likewise.
	* sysdeps/unix/sysv/linux/i386/Versions (libc) [GLIBC_PRIVATE):
	Add __uname.
2017-06-23 17:38:17 -03:00

105 lines
3.3 KiB
C

/* Copyright (C) 2002-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <signal.h>
#include <stdlib.h>
#include "pthreadP.h"
#include <atomic.h>
#include <sysdep.h>
#include <unistd.h>
int
__pthread_cancel (pthread_t th)
{
volatile struct pthread *pd = (volatile struct pthread *) th;
/* Make sure the descriptor is valid. */
if (INVALID_TD_P (pd))
/* Not a valid thread handle. */
return ESRCH;
#ifdef SHARED
pthread_cancel_init ();
#endif
int result = 0;
int oldval;
int newval;
do
{
again:
oldval = pd->cancelhandling;
newval = oldval | CANCELING_BITMASK | CANCELED_BITMASK;
/* Avoid doing unnecessary work. The atomic operation can
potentially be expensive if the bug has to be locked and
remote cache lines have to be invalidated. */
if (oldval == newval)
break;
/* If the cancellation is handled asynchronously just send a
signal. We avoid this if possible since it's more
expensive. */
if (CANCEL_ENABLED_AND_CANCELED_AND_ASYNCHRONOUS (newval))
{
/* Mark the cancellation as "in progress". */
if (atomic_compare_and_exchange_bool_acq (&pd->cancelhandling,
oldval | CANCELING_BITMASK,
oldval))
goto again;
#ifdef SIGCANCEL
/* The cancellation handler will take care of marking the
thread as canceled. */
pid_t pid = __getpid ();
INTERNAL_SYSCALL_DECL (err);
int val = INTERNAL_SYSCALL_CALL (tgkill, err, pid, pd->tid,
SIGCANCEL);
if (INTERNAL_SYSCALL_ERROR_P (val, err))
result = INTERNAL_SYSCALL_ERRNO (val, err);
#else
/* It should be impossible to get here at all, since
pthread_setcanceltype should never have allowed
PTHREAD_CANCEL_ASYNCHRONOUS to be set. */
abort ();
#endif
break;
}
/* A single-threaded process should be able to kill itself, since
there is nothing in the POSIX specification that says that it
cannot. So we set multiple_threads to true so that cancellation
points get executed. */
THREAD_SETMEM (THREAD_SELF, header.multiple_threads, 1);
#ifndef TLS_MULTIPLE_THREADS_IN_TCB
__pthread_multiple_threads = *__libc_multiple_threads_ptr = 1;
#endif
}
/* Mark the thread as canceled. This has to be done
atomically since other bits could be modified as well. */
while (atomic_compare_and_exchange_bool_acq (&pd->cancelhandling, newval,
oldval));
return result;
}
weak_alias (__pthread_cancel, pthread_cancel)
PTHREAD_STATIC_FN_REQUIRE (__pthread_create)