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			133 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			133 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Copyright (C) 2001-2014 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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|    Contributed by Ulrich Drepper <drepper@redhat.com>, 2001.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, see
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|    <http://www.gnu.org/licenses/>.  */
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| 
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| #include <netdb.h>
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| #include <pthread.h>
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| #include <stdlib.h>
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| #include <gai_misc.h>
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| 
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| 
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| struct notify_func
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|   {
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|     void (*func) (sigval_t);
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|     sigval_t value;
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|   };
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| 
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| static void *
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| notify_func_wrapper (void *arg)
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| {
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|   gai_start_notify_thread ();
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|   struct notify_func *const n = arg;
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|   void (*func) (sigval_t) = n->func;
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|   sigval_t value = n->value;
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|   free (n);
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|   (*func) (value);
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|   return NULL;
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| }
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| 
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| 
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| int
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| internal_function
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| __gai_notify_only (struct sigevent *sigev, pid_t caller_pid)
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| {
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|   int result = 0;
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| 
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|   /* Send the signal to notify about finished processing of the request.  */
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|   if (sigev->sigev_notify == SIGEV_THREAD)
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|     {
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|       /* We have to start a thread.  */
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|       pthread_t tid;
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|       pthread_attr_t attr, *pattr;
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| 
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|       pattr = (pthread_attr_t *) sigev->sigev_notify_attributes;
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|       if (pattr == NULL)
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| 	{
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| 	  pthread_attr_init (&attr);
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| 	  pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
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| 	  pattr = &attr;
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| 	}
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| 
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|       /* SIGEV may be freed as soon as we return, so we cannot let the
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| 	 notification thread use that pointer.  Even though a sigval_t is
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| 	 only one word and the same size as a void *, we cannot just pass
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| 	 the value through pthread_create as the argument and have the new
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| 	 thread run the user's function directly, because on some machines
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| 	 the calling convention for a union like sigval_t is different from
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| 	 that for a pointer type like void *.  */
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|       struct notify_func *nf = malloc (sizeof *nf);
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|       if (nf == NULL)
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| 	result = -1;
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|       else
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| 	{
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| 	  nf->func = sigev->sigev_notify_function;
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| 	  nf->value = sigev->sigev_value;
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| 	  if (pthread_create (&tid, pattr, notify_func_wrapper, nf) < 0)
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| 	    {
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| 	      free (nf);
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| 	      result = -1;
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| 	    }
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| 	}
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|     }
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|   else if (sigev->sigev_notify == SIGEV_SIGNAL)
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|     /* We have to send a signal.  */
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|     if (__gai_sigqueue (sigev->sigev_signo, sigev->sigev_value, caller_pid)
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| 	< 0)
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|       result = -1;
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| 
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|   return result;
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| }
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| 
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| 
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| void
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| internal_function
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| __gai_notify (struct requestlist *req)
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| {
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|   struct waitlist *waitlist;
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| 
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|   /* Now also notify possibly waiting threads.  */
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|   waitlist = req->waiting;
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|   while (waitlist != NULL)
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|     {
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|       struct waitlist *next = waitlist->next;
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| 
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|       if (waitlist->sigevp == NULL)
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| 	{
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| #ifdef DONT_NEED_GAI_MISC_COND
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| 	  GAI_MISC_NOTIFY (waitlist);
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| #else
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| 	  /* Decrement the counter.  */
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| 	  --*waitlist->counterp;
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| 
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| 	  pthread_cond_signal (waitlist->cond);
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| #endif
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| 	}
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|       else
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| 	/* This is part of an asynchronous `getaddrinfo_a' operation.  If
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| 	   this request is the last one, send the signal.  */
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| 	if (--*waitlist->counterp == 0)
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| 	  {
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| 	    __gai_notify_only (waitlist->sigevp, waitlist->caller_pid);
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| 	    /* This is tricky.  See getaddrinfo_a.c for the reason why
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| 	       this works.  */
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| 	    free ((void *) waitlist->counterp);
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| 	  }
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| 
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|       waitlist = next;
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|     }
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| }
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