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/* Copyright (C) 2002 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <assert.h>
#include <limits.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/param.h>
#include <sys/resource.h>
#include <pthreadP.h>
#include <atomic.h>
#include <ldsodefs.h>
#include <tls.h>
#include <fork.h>
#include <version.h>
/* XXX For the time being... */
#define __NR_set_tid_address 258
/* Default stack size. */
size_t __default_stacksize attribute_hidden;
/* Size and alignment of static TLS block. */
size_t __static_tls_size;
size_t __static_tls_align;
/* Version of the library, used in libthread_db to detect mismatches. */
static const char nptl_version[] = VERSION;
#if defined USE_TLS && !defined SHARED
extern void __libc_setup_tls (size_t tcbsize, size_t tcbalign);
#endif
/* For asynchronous cancellation we use a signal. This is the handler. */
static void
sigcancel_handler (int sig __attribute ((unused)))
{
struct pthread *self = THREAD_SELF;
while (1)
{
/* We are canceled now. When canceled by another thread this flag
is already set but if the signal is directly send (internally or
from another process) is has to be done here. */
int oldval = THREAD_GETMEM (self, cancelhandling);
int newval = oldval | CANCELED_BITMASK;
if (oldval == newval || (oldval & EXITING_BITMASK) != 0)
/* Already canceled or exiting. */
break;
if (atomic_compare_and_exchange_acq (&self->cancelhandling, newval,
oldval) == 0)
{
/* Set the return value. */
THREAD_SETMEM (self, result, PTHREAD_CANCELED);
/* Make sure asynchronous cancellation is still enabled. */
if ((newval & CANCELTYPE_BITMASK) != 0)
{
/* The thread is exiting now. */
atomic_bit_set (&self->cancelhandling, EXITING_BIT);
/* Run the registered destructors and terminate the
thread. */
__do_cancel (CURRENT_STACK_FRAME);
}
break;
}
}
}
void
#ifdef SHARED
__attribute ((constructor))
#endif
__pthread_initialize_minimal (void)
{
struct sigaction sa;
struct rlimit limit;
#ifdef USE_TLS
struct pthread *pd;
#endif
#ifndef SHARED
/* Unlike in the dynamically linked case the dynamic linker has not
taken care of initializing the TLS data structures. */
__libc_setup_tls (TLS_TCB_SIZE, TLS_TCB_ALIGN);
#endif
/* Minimal initialization of the thread descriptor. */
pd = THREAD_SELF;
pd->tid = INTERNAL_SYSCALL (set_tid_address, 1, &pd->tid);
THREAD_SETMEM (pd, specific[0], &pd->specific_1stblock[0]);
THREAD_SETMEM (pd, user_stack, true);
if (LLL_LOCK_INITIALIZER != 0)
THREAD_SETMEM (pd, lock, LLL_LOCK_INITIALIZER);
#if HP_TIMING_AVAIL
THREAD_SETMEM (pd, cpuclock_offset, GL(dl_cpuclock_offset));
#endif
/* Add the main thread to the list of all running threads. No need
to get the lock we are alone so far. */
list_add (&pd->header.data.list, &__stack_user);
/* Install the cancellation signal handler. If for some reason we
cannot install the handler we do not abort. Maybe we should, but
it is only asynchronous cancellation which is affected. */
sa.sa_handler = sigcancel_handler;
sa.sa_flags = 0;
/* Avoid another cancellation signal when we process one. */
sigemptyset (&sa.sa_mask);
sigaddset (&sa.sa_mask, SIGCANCEL);
(void) __libc_sigaction (SIGCANCEL, &sa, NULL);
/* Determine the default allowed stack size. This is the size used
in case the user does not specify one. */
if (getrlimit (RLIMIT_STACK, &limit) != 0
|| limit.rlim_cur == RLIM_INFINITY)
/* The system limit is not usable. Use an architecture-specific
default. */
limit.rlim_cur = ARCH_STACK_DEFAULT_SIZE;
#ifdef NEED_SEPARATE_REGISTER_STACK
__default_stacksize = MAX (limit.rlim_cur / 2, PTHREAD_STACK_MIN);
#else
__default_stacksize = MAX (limit.rlim_cur, PTHREAD_STACK_MIN);
#endif
/* The maximum page size better should be a multiple of the page
size. */
assert (__default_stacksize % __sysconf (_SC_PAGESIZE) == 0);
/* Get the size of the static and alignment requirements for the TLS
block. */
_dl_get_tls_static_info (&__static_tls_size, &__static_tls_align);
/* Make sure the size takes all the alignments into account. */
if (STACK_ALIGN > __static_tls_align)
__static_tls_align = STACK_ALIGN;
__static_tls_size = roundup (__static_tls_size, __static_tls_align);
/* Register the fork generation counter with the libc. */
__register_pthread_fork_handler (&__fork_generation, __reclaim_stacks);
}
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