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/* Copyright (C) 2002-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Jakub Jelinek <jakub@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 <sysdep.h>
#include <tls.h>
#ifndef __ASSEMBLER__
# include <nptl/pthreadP.h>
#endif
#if IS_IN (libc) || IS_IN (libpthread) || IS_IN (librt)
/* The code to disable cancellation depends on the fact that the called
functions are special. They don't modify registers other than %rax
and %r11 if they return. Therefore we don't have to preserve other
registers around these calls. */
# undef PSEUDO
# define PSEUDO(name, syscall_name, args) \
.text; \
ENTRY (name) \
SINGLE_THREAD_P; \
jne L(pseudo_cancel); \
.type __##syscall_name##_nocancel,@function; \
.globl __##syscall_name##_nocancel; \
__##syscall_name##_nocancel: \
DO_CALL (syscall_name, args); \
cmpq $-4095, %rax; \
jae SYSCALL_ERROR_LABEL; \
ret; \
.size __##syscall_name##_nocancel,.-__##syscall_name##_nocancel; \
L(pseudo_cancel): \
/* We always have to align the stack before calling a function. */ \
subq $8, %rsp; cfi_adjust_cfa_offset (8); \
CENABLE \
/* The return value from CENABLE is argument for CDISABLE. */ \
movq %rax, (%rsp); \
DO_CALL (syscall_name, args); \
movq (%rsp), %rdi; \
/* Save %rax since it's the error code from the syscall. */ \
movq %rax, %rdx; \
CDISABLE \
movq %rdx, %rax; \
addq $8,%rsp; cfi_adjust_cfa_offset (-8); \
cmpq $-4095, %rax; \
jae SYSCALL_ERROR_LABEL
# if IS_IN (libpthread)
# define CENABLE call __pthread_enable_asynccancel;
# define CDISABLE call __pthread_disable_asynccancel;
# define __local_multiple_threads __pthread_multiple_threads
# elif IS_IN (libc)
# define CENABLE call __libc_enable_asynccancel;
# define CDISABLE call __libc_disable_asynccancel;
# define __local_multiple_threads __libc_multiple_threads
# elif IS_IN (librt)
# define CENABLE call __librt_enable_asynccancel;
# define CDISABLE call __librt_disable_asynccancel;
# else
# error Unsupported library
# endif
# if IS_IN (libpthread) || IS_IN (libc)
# ifndef __ASSEMBLER__
extern int __local_multiple_threads attribute_hidden;
# define SINGLE_THREAD_P \
__builtin_expect (__local_multiple_threads == 0, 1)
# else
# define SINGLE_THREAD_P cmpl $0, __local_multiple_threads(%rip)
# endif
# else
# ifndef __ASSEMBLER__
# define SINGLE_THREAD_P \
__builtin_expect (THREAD_GETMEM (THREAD_SELF, \
header.multiple_threads) == 0, 1)
# else
# define SINGLE_THREAD_P cmpl $0, %fs:MULTIPLE_THREADS_OFFSET
# endif
# endif
#elif !defined __ASSEMBLER__
# define SINGLE_THREAD_P (1)
# define NO_CANCELLATION 1
#endif
#ifndef __ASSEMBLER__
# define RTLD_SINGLE_THREAD_P \
__builtin_expect (THREAD_GETMEM (THREAD_SELF, \
header.multiple_threads) == 0, 1)
#endif
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