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-rw-r--r--resolv/getaddrinfo_a.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/resolv/getaddrinfo_a.c b/resolv/getaddrinfo_a.c
new file mode 100644
index 0000000000..1a077d1bc7
--- /dev/null
+++ b/resolv/getaddrinfo_a.c
@@ -0,0 +1,168 @@
+/* Copyright (C) 2001 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2001.
+
+   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.  */
+
+#include <errno.h>
+#include <netdb.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "gai_misc.h"
+
+
+/* We need this special structure to handle asynchronous I/O.  */
+struct async_waitlist
+  {
+    int counter;
+    struct sigevent sigev;
+    struct waitlist list[0];
+  };
+
+
+int
+getaddrinfo_a (int mode, struct gaicb *list[], int ent, struct sigevent *sig)
+{
+  struct sigevent defsigev;
+  struct requestlist *requests[ent];
+  int cnt;
+  volatile int total = 0;
+  int result = 0;
+
+  /* Check arguments.  */
+  if (mode != GAI_WAIT && mode != GAI_NOWAIT)
+    {
+      __set_errno (EINVAL);
+      return EAI_SYSTEM;
+    }
+
+  if (sig == NULL)
+    {
+      defsigev.sigev_notify = SIGEV_NONE;
+      sig = &defsigev;
+    }
+
+  /* Request the mutex.  */
+  pthread_mutex_lock (&__gai_requests_mutex);
+
+  /* Now we can enqueue all requests.  Since we already acquired the
+     mutex the enqueue function need not do this.  */
+  for (cnt = 0; cnt < ent; ++cnt)
+    if (list[cnt] != NULL)
+      {
+	requests[cnt] = __gai_enqueue_request (list[cnt]);
+
+	if (requests[cnt] != NULL)
+	  /* Successfully enqueued.  */
+	  ++total;
+	else
+	  /* Signal that we've seen an error.  `errno' and the error code
+	     of the gaicb will tell more.  */
+	  result = EAI_SYSTEM;
+      }
+    else
+      requests[cnt] = NULL;
+
+  if (total == 0)
+    {
+      /* We don't have anything to do except signalling if we work
+	 asynchronously.  */
+
+      /* Release the mutex.  We do this before raising a signal since the
+	 signal handler might do a `siglongjmp' and then the mutex is
+	 locked forever.  */
+      pthread_mutex_unlock (&__gai_requests_mutex);
+
+      if (mode == GAI_NOWAIT)
+	__gai_notify_only (sig,
+			   sig->sigev_notify == SIGEV_SIGNAL ? getpid () : 0);
+
+      return result;
+    }
+  else if (mode == GAI_WAIT)
+    {
+      pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+      struct waitlist waitlist[ent];
+      int oldstate;
+
+      total = 0;
+      for (cnt = 0; cnt < ent; ++cnt)
+	if (requests[cnt] != NULL)
+	  {
+	    waitlist[cnt].cond = &cond;
+	    waitlist[cnt].next = requests[cnt]->waiting;
+	    waitlist[cnt].counterp = &total;
+	    waitlist[cnt].sigevp = NULL;
+	    waitlist[cnt].caller_pid = 0;	/* Not needed.  */
+	    requests[cnt]->waiting = &waitlist[cnt];
+	    ++total;
+	  }
+
+      /* 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);
+
+      while (total > 0)
+	pthread_cond_wait (&cond, &__gai_requests_mutex);
+
+      /* 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 ();
+    }
+  else
+    {
+      struct async_waitlist *waitlist;
+
+      waitlist = (struct async_waitlist *)
+	malloc (sizeof (struct async_waitlist)
+		+ (ent * sizeof (struct waitlist)));
+
+      if (waitlist == NULL)
+	result = EAI_AGAIN;
+      else
+	{
+	  pid_t caller_pid = sig->sigev_notify == SIGEV_SIGNAL ? getpid () : 0;
+	  total = 0;
+
+	  for (cnt = 0; cnt < ent; ++cnt)
+	    if (requests[cnt] != NULL)
+	      {
+		waitlist->list[cnt].cond = NULL;
+		waitlist->list[cnt].next = requests[cnt]->waiting;
+		waitlist->list[cnt].counterp = &waitlist->counter;
+		waitlist->list[cnt].sigevp = &waitlist->sigev;
+		waitlist->list[cnt].caller_pid = caller_pid;
+		requests[cnt]->waiting = &waitlist->list[cnt];
+		++total;
+	      }
+
+	  waitlist->counter = total;
+	  waitlist->sigev = *sig;
+	}
+    }
+
+  /* Release the mutex.  */
+  pthread_mutex_unlock (&__gai_requests_mutex);
+
+  return result;
+}