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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 <errno.h>
#include <stdlib.h>
#include "fork.h"
/* Defined in libc_pthread_init.c. */
extern struct fork_handler __pthread_child_handler attribute_hidden;
int
__register_atfork (prepare, parent, child, dso_handle)
void (*prepare) (void);
void (*parent) (void);
void (*child) (void);
void *dso_handle;
{
struct fork_handler *new_prepare = NULL;
struct fork_handler *new_parent = NULL;
struct fork_handler *new_child = NULL;
if (prepare != NULL)
{
new_prepare = (struct fork_handler *) malloc (sizeof (*new_prepare));
if (new_prepare == NULL)
goto out1;
new_prepare->handler = prepare;
new_prepare->dso_handle = dso_handle;
}
if (parent != NULL)
{
new_parent = (struct fork_handler *) malloc (sizeof (*new_parent));
if (new_parent == NULL)
goto out2;
new_parent->handler = parent;
new_parent->dso_handle = dso_handle;
}
if (child != NULL)
{
new_child = (struct fork_handler *) malloc (sizeof (*new_child));
if (new_child == NULL)
{
free (new_parent);
out2:
free (new_prepare);
out1:
return errno;
}
new_child->handler = child;
new_child->dso_handle = dso_handle;
}
/* Get the lock to not conflict with running forks. */
lll_lock (__fork_lock);
/* Now that we have all the handlers allocate enqueue them. */
if (new_prepare != NULL)
list_add_tail (&new_prepare->list, &__fork_prepare_list);
if (new_parent != NULL)
list_add_tail (&new_parent->list, &__fork_parent_list);
if (new_child != NULL)
list_add_tail (&new_child->list, &__fork_child_list);
/* Release the lock. */
lll_unlock (__fork_lock);
return 0;
}
/* Three static memory blocks used when registering malloc. */
static struct fork_handler malloc_prepare;
static struct fork_handler malloc_parent;
static struct fork_handler malloc_child;
void
attribute_hidden
__register_atfork_malloc (prepare, parent, child, dso_handle)
void (*prepare) (void);
void (*parent) (void);
void (*child) (void);
void *dso_handle;
{
/* Pre-fork handler. */
malloc_prepare.handler = prepare;
malloc_prepare.dso_handle = dso_handle;
/* Parent handler. */
malloc_parent.handler = parent;
malloc_parent.dso_handle = dso_handle;
/* Child handler. */
malloc_child.handler = child;
malloc_child.dso_handle = dso_handle;
/* Get the lock to not conflict with running forks. */
lll_lock (__fork_lock);
/* Now that we have all the handlers allocate enqueue them. */
list_add_tail (&malloc_prepare.list, &__fork_prepare_list);
list_add_tail (&malloc_parent.list, &__fork_parent_list);
list_add_tail (&malloc_child.list, &__fork_child_list);
/* Release the lock. */
lll_unlock (__fork_lock);
}
libc_freeres_fn (free_mem)
{
/* Get the lock to not conflict with running forks. */
lll_lock (__fork_lock);
list_t *runp;
list_t *prevp;
list_for_each_prev_safe (runp, prevp, &__fork_prepare_list)
{
list_del (runp);
struct fork_handler *p = list_entry (runp, struct fork_handler, list);
if (p != &malloc_prepare)
free (p);
}
list_for_each_prev_safe (runp, prevp, &__fork_parent_list)
{
list_del (runp);
struct fork_handler *p = list_entry (runp, struct fork_handler, list);
if (p != &malloc_parent)
free (p);
}
list_for_each_prev_safe (runp, prevp, &__fork_child_list)
{
list_del (runp);
struct fork_handler *p = list_entry (runp, struct fork_handler, list);
if (p != &__pthread_child_handler && p != &malloc_child)
free (p);
}
/* Release the lock. */
lll_unlock (__fork_lock);
}
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