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-rw-r--r--sysdeps/pthread/aio_suspend.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/sysdeps/pthread/aio_suspend.c b/sysdeps/pthread/aio_suspend.c
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index 0000000000..5ac2d23ffb
--- /dev/null
+++ b/sysdeps/pthread/aio_suspend.c
@@ -0,0 +1,151 @@
+/* Suspend until termination of a requests.
+   Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+
+/* We use an UGLY hack to prevent gcc from finding us cheating.  The
+   implementations of aio_suspend and aio_suspend64 are identical and so
+   we want to avoid code duplication by using aliases.  But gcc sees
+   the different parameter lists and prints a warning.  We define here
+   a function so that aio_suspend64 has no prototype.  */
+#define aio_suspend64 XXX
+#include <aio.h>
+/* And undo the hack.  */
+#undef aio_suspend64
+
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+#include "aio_misc.h"
+
+
+int
+aio_suspend (list, nent, timeout)
+     const struct aiocb *const list[];
+     int nent;
+     const struct timespec *timeout;
+{
+  struct waitlist waitlist[nent];
+  struct requestlist *requestlist[nent];
+  pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+  int cnt;
+  int result = 0;
+  int dummy;
+  int none = 1;
+
+  /* Request the mutex.  */
+  pthread_mutex_lock (&__aio_requests_mutex);
+
+  /* There is not yet a finished request.  Signal the request that
+     we are working for it.  */
+  for (cnt = 0; cnt < nent; ++cnt)
+    if (list[cnt] != NULL && list[cnt]->__error_code == EINPROGRESS)
+      {
+	requestlist[cnt] = __aio_find_req ((aiocb_union *) list[cnt]);
+
+	if (requestlist[cnt] != NULL)
+	  {
+	    waitlist[cnt].cond = &cond;
+	    waitlist[cnt].next = requestlist[cnt]->waiting;
+	    waitlist[cnt].counterp = &dummy;
+	    waitlist[cnt].sigevp = NULL;
+	    waitlist[cnt].caller_pid = 0;	/* Not needed.  */
+	    requestlist[cnt]->waiting = &waitlist[cnt];
+	    none = 0;
+	  }
+      }
+
+  /* If there is a not finished request wait for it.  */
+  if (!none)
+    {
+      int oldstate;
+
+      /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancelation
+	 points we must be careful.  We added entries to the waiting lists
+	 which we must remove.  So defer cancelation for now.  */
+      pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &oldstate);
+
+      if (timeout == NULL)
+	result = pthread_cond_wait (&cond, &__aio_requests_mutex);
+      else
+	{
+	  /* We have to convert the relative timeout value into an
+	     absolute time value with pthread_cond_timedwait expects.  */
+	  struct timeval now;
+	  struct timespec abstime;
+
+	  __gettimeofday (&now, NULL);
+	  abstime.tv_nsec = timeout->tv_nsec + now.tv_usec * 1000;
+	  abstime.tv_sec = timeout->tv_sec + now.tv_sec;
+	  if (abstime.tv_nsec >= 1000000000)
+	    {
+	      abstime.tv_nsec -= 1000000000;
+	      abstime.tv_sec += 1;
+	    }
+
+	  result = pthread_cond_timedwait (&cond, &__aio_requests_mutex,
+					   &abstime);
+	}
+
+      /* Now remove the entry in the waiting list for all requests
+	 which didn't terminate.  */
+      for (cnt = 0; cnt < nent; ++cnt)
+	if (list[cnt] != NULL && list[cnt]->__error_code == EINPROGRESS
+	    && requestlist[cnt] != NULL)
+	  {
+	    struct waitlist **listp = &requestlist[cnt]->waiting;
+
+	    /* There is the chance that we cannot find our entry anymore.
+	       This could happen if the request terminated and restarted
+	       again.  */
+	    while (*listp != NULL && *listp != &waitlist[cnt])
+	      listp = &(*listp)->next;
+
+	    if (*listp != NULL)
+	      *listp = (*listp)->next;
+	  }
+
+      /* Now it's time to restore the cancelation state.  */
+      pthread_setcancelstate (oldstate, NULL);
+
+      /* Release the conditional variable.  */
+      if (pthread_cond_destroy (&cond) != 0)
+	/* This must never happen.  */
+	abort ();
+
+      if (result != 0)
+	{
+	  /* An error occurred.  Possibly it's EINTR.  We have to translate
+	     the timeout error report of `pthread_cond_timedwait' to the
+	     form expected from `aio_suspend'.  */
+	  if (result == ETIMEDOUT)
+	    __set_errno (EAGAIN);
+
+	  result = -1;
+	}
+    }
+
+  /* Release the mutex.  */
+  pthread_mutex_unlock (&__aio_requests_mutex);
+
+  return result;
+}
+
+weak_alias (aio_suspend, aio_suspend64)