nptl_db/td_thr_validate.c

   1 /* Validate a thread handle.
   2    Copyright (C) 1999, 2001, 2002, 2003, 2004 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, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include "thread_dbP.h"
  22 #include <stdbool.h>
  23
  24 static td_err_e
  25 check_thread_list (const td_thrhandle_t *th, psaddr_t head, bool *uninit)
  26 {
  27   td_err_e err;
  28   psaddr_t next, ofs;
  29
  30   err = DB_GET_FIELD (next, th->th_ta_p, head, list_t, next, 0);
  31   if (err == TD_OK)
  32     {
  33       if (next == 0)
  34         {
  35           *uninit = true;
  36           return TD_NOTHR;
  37         }
  38       err = DB_GET_FIELD_ADDRESS (ofs, th->th_ta_p, 0, pthread, list, 0);
  39     }
  40
  41   while (err == TD_OK)
  42     {
  43       if (next == head)
  44         return TD_NOTHR;
  45
  46       if (next - (ofs - (psaddr_t) 0) == th->th_unique)
  47         return TD_OK;
  48
  49       err = DB_GET_FIELD (next, th->th_ta_p, next, list_t, next, 0);
  50     }
  51
  52   return err;
  53 }
  54
  55
  56 td_err_e
  57 td_thr_validate (const td_thrhandle_t *th)
  58 {
  59   td_err_e err;
  60   psaddr_t list;
  61
  62   LOG ("td_thr_validate");
  63
  64   /* First check the list with threads using user allocated stacks.  */
  65   bool uninit = false;
  66   err = DB_GET_SYMBOL (list, th->th_ta_p, __stack_user);
  67   if (err == TD_OK)
  68     err = check_thread_list (th, list, &uninit);
  69
  70   /* If our thread is not on this list search the list with stack
  71      using implementation allocated stacks.  */
  72   if (err == TD_NOTHR)
  73     {
  74       err = DB_GET_SYMBOL (list, th->th_ta_p, stack_used);
  75       if (err == TD_OK)
  76         err = check_thread_list (th, list, &uninit);
  77
  78       if (err == TD_NOTHR && uninit)
  79         {
  80           /* __pthread_initialize_minimal has not run yet.
  81              But the main thread still has a valid ID.  */
  82           td_thrhandle_t main_th;
  83           err = td_ta_map_lwp2thr (th->th_ta_p,
  84                                    ps_getpid (th->th_ta_p->ph), &main_th);
  85           if (err == TD_OK && th->th_unique != main_th.th_unique)
  86             err = TD_NOTHR;
  87         }
  88     }
  89
  90   return err;
  91 }