Permalink
Cannot retrieve contributors at this time
Name already in use
A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
glibc/nptl/libc_pthread_init.c
Go to fileThis commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
88 lines (73 sloc)
2.5 KB
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
/* Copyright (C) 2002-2016 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 <unistd.h> | |
#include <list.h> | |
#include <fork.h> | |
#include <dl-sysdep.h> | |
#include <tls.h> | |
#include <string.h> | |
#include <pthreadP.h> | |
#include <libc-lock.h> | |
#include <sysdep.h> | |
#include <ldsodefs.h> | |
unsigned long int *__fork_generation_pointer; | |
#ifdef TLS_MULTIPLE_THREADS_IN_TCB | |
void | |
#else | |
extern int __libc_multiple_threads attribute_hidden; | |
int * | |
#endif | |
internal_function | |
__libc_pthread_init (unsigned long int *ptr, void (*reclaim) (void), | |
const struct pthread_functions *functions) | |
{ | |
/* Remember the pointer to the generation counter in libpthread. */ | |
__fork_generation_pointer = ptr; | |
/* Called by a child after fork. */ | |
__register_atfork (NULL, NULL, reclaim, NULL); | |
#ifdef SHARED | |
/* Copy the function pointers into an array in libc. This enables | |
access with just one memory reference but moreso, it prevents | |
hijacking the function pointers with just one pointer change. We | |
"encrypt" the function pointers since we cannot write-protect the | |
array easily enough. */ | |
union ptrhack | |
{ | |
struct pthread_functions pf; | |
# define NPTRS (sizeof (struct pthread_functions) / sizeof (void *)) | |
void *parr[NPTRS]; | |
} __attribute__ ((may_alias)) const *src; | |
union ptrhack *dest; | |
src = (const void *) functions; | |
dest = (void *) &__libc_pthread_functions; | |
for (size_t cnt = 0; cnt < NPTRS; ++cnt) | |
{ | |
void *p = src->parr[cnt]; | |
PTR_MANGLE (p); | |
dest->parr[cnt] = p; | |
} | |
__libc_pthread_functions_init = 1; | |
#endif | |
#ifndef TLS_MULTIPLE_THREADS_IN_TCB | |
return &__libc_multiple_threads; | |
#endif | |
} | |
#ifdef SHARED | |
libc_freeres_fn (freeres_libptread) | |
{ | |
if (__libc_pthread_functions_init) | |
PTHFCT_CALL (ptr_freeres, ()); | |
} | |
#endif |