1 /* Validate a thread handle.
2    Copyright (C) 1999,2001,2002,2003,2004,2007 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4    Contributed by Ulrich Drepper <drepper@redhat.com>, 1999.
5 
6    The GNU C Library is free software; you can redistribute it and/or
7    modify it under the terms of the GNU Lesser General Public
8    License as published by the Free Software Foundation; either
9    version 2.1 of the License, or (at your option) any later version.
10 
11    The GNU C Library is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14    Lesser General Public License for more details.
15 
16    You should have received a copy of the GNU Lesser General Public
17    License along with the GNU C Library; if not, see
18    <http://www.gnu.org/licenses/>.  */
19 
20 #include "thread_dbP.h"
21 #include <stdbool.h>
22 
23 static td_err_e
check_thread_list(const td_thrhandle_t * th,psaddr_t head,bool * uninit)24 check_thread_list (const td_thrhandle_t *th, psaddr_t head, bool *uninit)
25 {
26   td_err_e err;
27   psaddr_t next, ofs;
28 
29   err = DB_GET_FIELD (next, th->th_ta_p, head, list_t, next, 0);
30   if (err == TD_OK)
31     {
32       if (next == 0)
33 	{
34 	  *uninit = true;
35 	  return TD_NOTHR;
36 	}
37       err = DB_GET_FIELD_ADDRESS (ofs, th->th_ta_p, 0, pthread, list, 0);
38     }
39 
40   while (err == TD_OK)
41     {
42       if (next == head)
43 	return TD_NOTHR;
44 
45       if (next - (ofs - (psaddr_t) 0) == th->th_unique)
46 	return TD_OK;
47 
48       err = DB_GET_FIELD (next, th->th_ta_p, next, list_t, next, 0);
49     }
50 
51   return err;
52 }
53 
54 
55 td_err_e
td_thr_validate(const td_thrhandle_t * th)56 td_thr_validate (const td_thrhandle_t *th)
57 {
58   td_err_e err;
59   psaddr_t list = NULL;
60 
61   LOG ("td_thr_validate");
62 
63   /* First check the list with threads using user allocated stacks.  */
64   bool uninit = false;
65   err = DB_GET_SYMBOL (list, th->th_ta_p, __stack_user);
66   if (err == TD_OK)
67     err = check_thread_list (th, list, &uninit);
68 
69   /* If our thread is not on this list search the list with stack
70      using implementation allocated stacks.  */
71   if (err == TD_NOTHR)
72     {
73       err = DB_GET_SYMBOL (list, th->th_ta_p, stack_used);
74       if (err == TD_OK)
75 	err = check_thread_list (th, list, &uninit);
76 
77       if (err == TD_NOTHR && uninit && th->th_unique == 0)
78 	/* __pthread_initialize_minimal has not run yet.
79 	   There is only the special case thread handle.  */
80 	err = TD_OK;
81     }
82 
83   return err;
84 }
85