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			108 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			108 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Validate a thread handle.
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|    Copyright (C) 1999-2014 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>, 1999.
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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 "thread_dbP.h"
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| #include <stdbool.h>
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| 
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| static td_err_e
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| check_thread_list (const td_thrhandle_t *th, psaddr_t head, bool *uninit)
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| {
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|   td_err_e err;
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|   psaddr_t next, ofs;
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| 
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|   err = DB_GET_FIELD (next, th->th_ta_p, head, list_t, next, 0);
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|   if (err == TD_OK)
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|     {
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|       if (next == 0)
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| 	{
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| 	  *uninit = true;
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| 	  return TD_NOTHR;
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| 	}
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|       err = DB_GET_FIELD_ADDRESS (ofs, th->th_ta_p, 0, pthread, list, 0);
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|     }
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| 
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|   while (err == TD_OK)
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|     {
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|       if (next == head)
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| 	return TD_NOTHR;
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| 
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|       if (next - (ofs - (psaddr_t) 0) == th->th_unique)
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| 	return TD_OK;
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| 
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|       err = DB_GET_FIELD (next, th->th_ta_p, next, list_t, next, 0);
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|     }
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| 
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|   return err;
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| }
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| 
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| 
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| td_err_e
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| td_thr_validate (const td_thrhandle_t *th)
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| {
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|   td_err_e err;
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|   psaddr_t list;
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| 
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|   LOG ("td_thr_validate");
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| 
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|   /* First check the list with threads using user allocated stacks.  */
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|   bool uninit = false;
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|   err = DB_GET_SYMBOL (list, th->th_ta_p, __stack_user);
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|   if (err == TD_OK)
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|     err = check_thread_list (th, list, &uninit);
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| 
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|   /* If our thread is not on this list search the list with stack
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|      using implementation allocated stacks.  */
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|   if (err == TD_NOTHR)
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|     {
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|       err = DB_GET_SYMBOL (list, th->th_ta_p, stack_used);
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|       if (err == TD_OK)
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| 	err = check_thread_list (th, list, &uninit);
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| 
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|       if (err == TD_NOTHR && uninit && th->th_unique == 0)
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| 	/* __pthread_initialize_minimal has not run yet.
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| 	   There is only the special case thread handle.  */
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| 	err = TD_OK;
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|     }
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| 
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|   if (err == TD_OK)
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|     {
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|       /* Verify that this is not a stale element in a fork child.  */
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|       pid_t match_pid = ps_getpid (th->th_ta_p->ph);
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|       psaddr_t pid;
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|       err = DB_GET_FIELD (pid, th->th_ta_p, th->th_unique, pthread, pid, 0);
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|       if (err == TD_OK && (pid_t) (uintptr_t) pid < 0)
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| 	{
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| 	  /* This was a thread that was about to fork, or it is the new sole
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| 	     thread in a fork child.  In the latter case, its tid was stored
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| 	     via CLONE_CHILD_SETTID and so is already the proper child PID.  */
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| 	  if (-(pid_t) (uintptr_t) pid == match_pid)
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| 	    /* It is about to do a fork, but is really still the parent PID.  */
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| 	    pid = (psaddr_t) (uintptr_t) match_pid;
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| 	  else
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| 	    /* It must be a fork child, whose new PID is in the tid field.  */
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| 	    err = DB_GET_FIELD (pid, th->th_ta_p, th->th_unique,
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| 				pthread, tid, 0);
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| 	}
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|       if (err == TD_OK && (pid_t) (uintptr_t) pid != match_pid)
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| 	err = TD_NOTHR;
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|     }
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| 
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|   return err;
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| }
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