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/*
* David Leonard <d@openbsd.org>, 1999. Public domain.
* $OpenBSD: uthread_atfork.c,v 1.1 1999/01/17 23:46:26 d Exp $
*/
#include <stdlib.h>
#include <sys/queue.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
struct atfork_entry {
void (*handler)(void);
TAILQ_ENTRY(atfork_entry) entries;
};
static TAILQ_HEAD(atfork_list, atfork_entry) atfork_head[3] =
{ TAILQ_HEAD_INITIALIZER(atfork_head[PTHREAD_ATFORK_PREPARE]),
TAILQ_HEAD_INITIALIZER(atfork_head[PTHREAD_ATFORK_PARENT]),
TAILQ_HEAD_INITIALIZER(atfork_head[PTHREAD_ATFORK_CHILD]) };
void
_thread_atfork(which)
{
struct atfork_list *head;
struct atfork_entry *ae;
head = &atfork_head[which];
/* Call the fork handlers in order: */
for (ae = head->tqh_first; ae != NULL; ae = ae->entries.tqe_next)
(*ae->handler)();
}
int
pthread_atfork(prepare, parent, child)
void (*prepare)(void);
void (*parent)(void);
void (*child)(void);
{
int ret = 0;
struct atfork_entry *prepare_entry = NULL;
struct atfork_entry *parent_entry = NULL;
struct atfork_entry *child_entry = NULL;
if (ret == 0 && prepare != NULL) {
/* Allocate space for the prepare handler: */
if ((prepare_entry = malloc(sizeof *prepare_entry)) != NULL)
prepare_entry->handler = prepare;
else
ret = -1;
}
if (ret == 0 && parent != NULL) {
/* Allocate space for the parent handler: */
if ((parent_entry = malloc(sizeof *parent_entry)) != NULL)
parent_entry->handler = parent;
else
ret = -1;
}
if (ret == 0 && child != NULL) {
/* Allocate space for the child handler: */
if ((child_entry = malloc(sizeof *child_entry)) != NULL)
child_entry->handler = child;
else
ret = -1;
}
if (ret == 0) {
/* Insert the handlers into the handler lists: */
if (prepare_entry != NULL)
TAILQ_INSERT_HEAD(&atfork_head[PTHREAD_ATFORK_PREPARE],
prepare_entry, entries);
if (parent_entry != NULL)
TAILQ_INSERT_TAIL(&atfork_head[PTHREAD_ATFORK_PARENT],
parent_entry, entries);
if (child_entry != NULL)
TAILQ_INSERT_TAIL(&atfork_head[PTHREAD_ATFORK_CHILD],
child_entry, entries);
} else {
/* Release unused resources: */
if (prepare_entry)
free(prepare_entry);
if (child_entry)
free(child_entry);
if (parent_entry)
free(parent_entry);
}
return (ret);
}
#endif
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