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/* Copyright (C) 2002, 2003 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 <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sysdep.h>
#include <libio/libioP.h>
#include <tls.h>
#include "fork.h"
#include <bits/stdio-lock.h>
#include <assert.h>
unsigned long int *__fork_generation_pointer;
lll_lock_t __fork_lock = LLL_LOCK_INITIALIZER;
LIST_HEAD (__fork_prepare_list);
LIST_HEAD (__fork_parent_list);
LIST_HEAD (__fork_child_list);
static void
fresetlockfiles (void)
{
_IO_ITER i;
for (i = _IO_iter_begin(); i != _IO_iter_end(); i = _IO_iter_next(i))
_IO_lock_init (*((_IO_lock_t *) _IO_iter_file(i)->_lock));
}
pid_t
__libc_fork (void)
{
pid_t pid;
list_t *runp;
/* Get the lock so that the set of registered handlers is not
inconsistent or changes beneath us. */
lll_lock (__fork_lock);
/* Run all the registered preparation handlers. In reverse order. */
list_for_each_prev (runp, &__fork_prepare_list)
{
struct fork_handler *curp;
curp = list_entry (runp, struct fork_handler, list);
curp->handler ();
}
_IO_list_lock ();
#ifndef NDEBUG
pid_t ppid = THREAD_GETMEM (THREAD_SELF, tid);
#endif
#ifdef ARCH_FORK
pid = ARCH_FORK ();
#else
# error "ARCH_FORK must be defined so that the CLONE_SETTID flag is used"
pid = INLINE_SYSCALL (fork, 0);
#endif
if (pid == 0)
{
assert (THREAD_GETMEM (THREAD_SELF, tid) != ppid);
if (__fork_generation_pointer != NULL)
*__fork_generation_pointer += 4;
/* Reset the file list. These are recursive mutexes. */
fresetlockfiles ();
/* Reset locks in the I/O code. */
_IO_list_resetlock ();
/* Run the handlers registered for the child. */
list_for_each (runp, &__fork_child_list)
{
struct fork_handler *curp;
curp = list_entry (runp, struct fork_handler, list);
curp->handler ();
}
/* Initialize the fork lock. */
__fork_lock = (lll_lock_t) LLL_LOCK_INITIALIZER;
}
else
{
assert (THREAD_GETMEM (THREAD_SELF, tid) == ppid);
/* We execute this even if the 'fork' call failed. */
_IO_list_unlock ();
/* Run the handlers registered for the parent. */
list_for_each (runp, &__fork_parent_list)
{
struct fork_handler *curp;
curp = list_entry (runp, struct fork_handler, list);
curp->handler ();
}
/* Release the for lock. */
lll_unlock (__fork_lock);
}
return pid;
}
weak_alias (__libc_fork, __fork)
weak_alias (__libc_fork, fork)
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