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/* Copyright (C) 2003, 2005, 2006, 2009 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@redhat.com>.
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; see the file COPYING.LIB. If
not, see <http://www.gnu.org/licenses/>. */
#include <dlfcn.h>
#include <stdio.h>
#include <unwind.h>
#include <pthreadP.h>
#include <sysdep.h>
#include <libgcc_s.h>
#include <unwind-resume.h>
#define __libc_dlopen(x) dlopen(x, (RTLD_LOCAL | RTLD_LAZY))
#define __libc_dlsym dlsym
#define __libc_dlclose dlclose
static void *libgcc_s_handle;
void (*__libgcc_s_resume) (struct _Unwind_Exception *exc)
attribute_hidden __attribute__ ((noreturn));
static _Unwind_Reason_Code (*libgcc_s_personality) PERSONALITY_PROTO;
static _Unwind_Reason_Code (*libgcc_s_forcedunwind)
(struct _Unwind_Exception *, _Unwind_Stop_Fn, void *);
static _Unwind_Word (*libgcc_s_getcfa) (struct _Unwind_Context *);
static void (*libgcc_s_sjlj_register) (struct SjLj_Function_Context *);
static void (*libgcc_s_sjlj_unregister) (struct SjLj_Function_Context *);
void
__attribute_noinline__
pthread_cancel_init (void)
{
void *resume;
void *personality;
void *forcedunwind;
void *getcfa;
void *handle;
void *sjlj_register, *sjlj_unregister;
if (__builtin_expect (libgcc_s_handle != NULL, 1))
{
/* Force gcc to reload all values. */
__asm__ __volatile__ ("" ::: "memory");
return;
}
handle = __libc_dlopen (LIBGCC_S_SO);
resume = __libc_dlsym (handle, "_Unwind_SjLj_Resume");
personality = __libc_dlsym (handle, "__gcc_personality_sj0");
forcedunwind = __libc_dlsym (handle, "_Unwind_SjLj_ForcedUnwind");
getcfa = __libc_dlsym (handle, "_Unwind_GetCFA");
sjlj_register = __libc_dlsym (handle, "_Unwind_SjLj_Register");
sjlj_unregister = __libc_dlsym (handle, "_Unwind_SjLj_Unregister");
if ((handle == NULL)
|| (resume == NULL)
|| (personality == NULL)
|| (forcedunwind == NULL)
|| (getcfa == NULL)
|| (sjlj_register == NULL)
|| (sjlj_unregister == NULL)
#ifdef ARCH_CANCEL_INIT
|| ARCH_CANCEL_INIT (handle)
#endif
)
{
fprintf (stderr,
LIBGCC_S_SO " must be installed for pthread_cancel to work\n");
abort();
}
__libgcc_s_resume = resume;
libgcc_s_personality = personality;
libgcc_s_forcedunwind = forcedunwind;
libgcc_s_sjlj_register = sjlj_register;
libgcc_s_sjlj_unregister = sjlj_unregister;
libgcc_s_getcfa = getcfa;
/* Make sure libgcc_s_handle is written last. Otherwise,
pthread_cancel_init might return early even when the pointer the
caller is interested in is not initialized yet. */
atomic_write_barrier ();
libgcc_s_handle = handle;
}
void
__libc_freeres_fn_section
__unwind_freeres (void)
{
void *handle = libgcc_s_handle;
if (handle != NULL)
{
libgcc_s_handle = NULL;
__libc_dlclose (handle);
}
}
#if !HAVE_ARCH_UNWIND_RESUME
void attribute_hidden
_Unwind_Resume (struct _Unwind_Exception *exc)
{
if (__builtin_expect (libgcc_s_handle == NULL, 0))
pthread_cancel_init ();
__libgcc_s_resume(exc);
}
#endif
_Unwind_Reason_Code attribute_hidden
__gcc_personality_v0 PERSONALITY_PROTO
{
if (__builtin_expect (libgcc_s_handle == NULL, 0))
pthread_cancel_init ();
return libgcc_s_personality PERSONALITY_ARGS;
}
_Unwind_Reason_Code attribute_hidden
_Unwind_ForcedUnwind (struct _Unwind_Exception *exc, _Unwind_Stop_Fn stop,
void *stop_argument)
{
if (__builtin_expect (libgcc_s_handle == NULL, 0))
pthread_cancel_init ();
return libgcc_s_forcedunwind (exc, stop, stop_argument);
}
_Unwind_Word attribute_hidden
_Unwind_GetCFA (struct _Unwind_Context *context)
{
if (__builtin_expect (libgcc_s_handle == NULL, 0))
pthread_cancel_init ();
return libgcc_s_getcfa (context);
}
void
_Unwind_SjLj_Register (struct SjLj_Function_Context *fc)
{
if (__builtin_expect (libgcc_s_sjlj_register == NULL, 0))
pthread_cancel_init ();
libgcc_s_sjlj_register (fc);
}
void
_Unwind_SjLj_Unregister (struct SjLj_Function_Context *fc)
{
if (__builtin_expect (libgcc_s_sjlj_unregister == NULL, 0))
pthread_cancel_init ();
libgcc_s_sjlj_unregister (fc);
}
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