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			63 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* pthread_once.  Generic version.
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|    Copyright (C) 2002-2025 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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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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|    <https://www.gnu.org/licenses/>.  */
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| 
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| #include <pthread.h>
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| #include <atomic.h>
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| 
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| #include <pt-internal.h>
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| #include <shlib-compat.h>
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| 
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| static void
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| clear_once_control (void *arg)
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| {
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|   pthread_once_t *once_control = arg;
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|   __pthread_spin_unlock (&once_control->__lock);
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| }
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| 
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| int
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| __pthread_once (pthread_once_t *once_control, void (*init_routine) (void))
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| {
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|   ASSERT_TYPE_SIZE (pthread_once_t, __SIZEOF_PTHREAD_ONCE_T);
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| 
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|   atomic_full_barrier ();
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|   if (once_control->__run == 0)
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|     {
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|       __pthread_spin_wait (&once_control->__lock);
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| 
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|       if (once_control->__run == 0)
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| 	{
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| 	  pthread_cleanup_push (clear_once_control, once_control);
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| 	  init_routine ();
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| 	  pthread_cleanup_pop (0);
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| 
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| 	  atomic_full_barrier ();
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| 	  once_control->__run = 1;
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| 	}
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| 
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|       __pthread_spin_unlock (&once_control->__lock);
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|     }
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| 
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|   return 0;
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| }
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| libc_hidden_def (__pthread_once)
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| versioned_symbol (libc, __pthread_once, pthread_once, GLIBC_2_42);
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| 
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| #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_12, GLIBC_2_42)
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| compat_symbol (libpthread, __pthread_once, pthread_once, GLIBC_2_12);
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| #endif
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