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diff --git a/nptl/sysdeps/pthread/gai_misc.h b/nptl/sysdeps/pthread/gai_misc.h
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+/* Copyright (C) 2006 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ 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. */
+
+/* We define a special synchronization primitive for AIO. POSIX
+ conditional variables would be ideal but the pthread_cond_*wait
+ operations do not return on EINTR. This is a requirement for
+ correct aio_suspend and lio_listio implementations. */
+
+#include <assert.h>
+#include <signal.h>
+#include <pthreadP.h>
+#include <lowlevellock.h>
+
+#define DONT_NEED_GAI_MISC_COND 1
+
+#define GAI_MISC_NOTIFY(waitlist) \
+ do { \
+ if (*waitlist->counterp > 0 && --*waitlist->counterp == 0) \
+ lll_futex_wake (waitlist->counterp, 1); \
+ } while (0)
+
+#define GAI_MISC_WAIT(result, futex, timeout, cancel) \
+ do { \
+ volatile int *futexaddr = &futex; \
+ int oldval = futex; \
+ \
+ if (oldval != 0) \
+ { \
+ pthread_mutex_unlock (&__gai_requests_mutex); \
+ \
+ int oldtype; \
+ if (cancel) \
+ oldtype = LIBC_CANCEL_ASYNC (); \
+ \
+ int status; \
+ do \
+ { \
+ status = lll_futex_timed_wait (futexaddr, oldval, timeout); \
+ if (status != -EWOULDBLOCK) \
+ break; \
+ \
+ oldval = *futexaddr; \
+ } \
+ while (oldval != 0); \
+ \
+ if (cancel) \
+ LIBC_CANCEL_RESET (oldtype); \
+ \
+ if (status == -EINTR) \
+ result = EINTR; \
+ else if (status == -ETIMEDOUT) \
+ result = EAGAIN; \
+ else \
+ assert (status == 0 || status == -EWOULDBLOCK); \
+ \
+ pthread_mutex_lock (&__gai_requests_mutex); \
+ } \
+ } while (0)
+
+
+#define gai_start_notify_thread __gai_start_notify_thread
+#define gai_create_helper_thread __gai_create_helper_thread
+
+extern inline void
+__gai_start_notify_thread (void)
+{
+ sigset_t ss;
+ sigemptyset (&ss);
+ INTERNAL_SYSCALL_DECL (err);
+ INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &ss, NULL, _NSIG / 8);
+}
+
+extern inline int
+__gai_create_helper_thread (pthread_t *threadp, void *(*tf) (void *),
+ void *arg)
+{
+ pthread_attr_t attr;
+
+ /* Make sure the thread is created detached. */
+ pthread_attr_init (&attr);
+ pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
+
+ /* The helper thread needs only very little resources. */
+ (void) pthread_attr_setstacksize (&attr, PTHREAD_STACK_MIN);
+
+ /* Block all signals in the helper thread. To do this thoroughly we
+ temporarily have to block all signals here. */
+ sigset_t ss;
+ sigset_t oss;
+ sigfillset (&ss);
+ INTERNAL_SYSCALL_DECL (err);
+ INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &ss, &oss, _NSIG / 8);
+
+ int ret = pthread_create (threadp, &attr, tf, arg);
+
+ /* Restore the signal mask. */
+ INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &oss, NULL,
+ _NSIG / 8);
+
+ (void) pthread_attr_destroy (&attr);
+ return ret;
+}
+
+#include_next <gai_misc.h>