linuxthreads_db/td_ta_thr_iter.c

   1 /* Iterate over a process's threads.
   2    Copyright (C) 1999,2000,2001,2002,2003 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.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 <linuxthreads/internals.h>
  23 #include <alloca.h>
  24
  25 static int
  26 handle_descr (const td_thragent_t *ta, td_thr_iter_f *callback,
  27               void *cbdata_p, td_thr_state_e state, int ti_pri,
  28               size_t cnt, pthread_descr descr)
  29 {
  30   struct _pthread_descr_struct pds;
  31   size_t sizeof_descr = ta->sizeof_descr;
  32   td_thrhandle_t th;
  33
  34   if (descr == NULL)
  35     {
  36       /* No descriptor (yet).  */
  37       if (cnt == 0)
  38         {
  39           /* This is the main thread.  Create a fake descriptor.  */
  40           memset (&pds, '\0', sizeof (pds));
  41
  42           /* Empty thread descriptor the thread library would create.  */
  43 #if !defined USE_TLS || !TLS_DTV_AT_TP
  44           pds.p_header.data.self = &pds;
  45 #endif
  46           pds.p_nextlive = pds.p_prevlive = &pds;
  47           pds.p_tid = PTHREAD_THREADS_MAX;
  48           /* The init code also sets up p_lock, p_errnop, p_herrnop, and
  49              p_userstack but this should not be necessary here.  */
  50
  51           th.th_ta_p = (td_thragent_t *) ta;
  52           th.th_unique = NULL;
  53           if (callback (&th, cbdata_p) != 0)
  54             return TD_DBERR;
  55
  56           /* All done successfully.  */
  57           return TD_OK;
  58         }
  59       else if (cnt == 1)
  60         /* The manager is not yet started.  No big deal.  */
  61         return TD_OK;
  62       else
  63         /* For every other thread this should not happen.  */
  64         return TD_ERR;
  65     }
  66
  67   if (ps_pdread (ta->ph, descr, &pds, sizeof_descr) != PS_OK)
  68     return TD_ERR;      /* XXX Other error value?  */
  69
  70   /* The manager thread must be handled special.  The descriptor
  71      exists but the thread only gets created when the first
  72      `pthread_create' call is issued.  A clear indication that this
  73      happened is when the p_pid field is non-zero.  */
  74   if (cnt == 1 && pds.p_pid == 0)
  75     return TD_OK;
  76
  77   /* Now test whether this thread matches the specified
  78      conditions.  */
  79
  80   /* Only if the priority level is as high or higher.  */
  81   if (pds.p_priority < ti_pri)
  82     return TD_OK;
  83
  84   /* Test the state.
  85      XXX This is incomplete.  */
  86   if (state != TD_THR_ANY_STATE)
  87     return TD_OK;
  88
  89   /* XXX For now we ignore threads which are not running anymore.
  90      The reason is that gdb tries to get the registers and fails.
  91      In future we should have a special mode of the thread library
  92      in which we keep the process around until the actual join
  93      operation happened.  */
  94   if (pds.p_exited != 0)
  95     return TD_OK;
  96
  97   /* Yep, it matches.  Call the callback function.  */
  98   th.th_ta_p = (td_thragent_t *) ta;
  99   th.th_unique = descr;
 100   if (callback (&th, cbdata_p) != 0)
 101     return TD_DBERR;
 102
 103   /* All done successfully.  */
 104   return TD_OK;
 105 }
 106
 107
 108 td_err_e
 109 td_ta_thr_iter (const td_thragent_t *ta, td_thr_iter_f *callback,
 110                 void *cbdata_p, td_thr_state_e state, int ti_pri,
 111                 sigset_t *ti_sigmask_p, unsigned int ti_user_flags)
 112 {
 113   int pthread_threads_max;
 114   struct pthread_handle_struct *phc;
 115   td_err_e result = TD_OK;
 116   int cnt;
 117 #ifdef ALL_THREADS_STOPPED
 118   int num;
 119 #else
 120 # define num 1
 121 #endif
 122
 123   LOG ("td_ta_thr_iter");
 124
 125   /* Test whether the TA parameter is ok.  */
 126   if (! ta_ok (ta))
 127     return TD_BADTA;
 128
 129   pthread_threads_max = ta->pthread_threads_max;
 130   phc = (struct pthread_handle_struct *) alloca (sizeof (phc[0])
 131                                                  * pthread_threads_max);
 132
 133   /* First read only the main thread and manager thread information.  */
 134   if (ps_pdread (ta->ph, ta->handles, phc,
 135                  sizeof (struct pthread_handle_struct) * 2) != PS_OK)
 136     return TD_ERR;      /* XXX Other error value?  */
 137
 138   /* Now handle these descriptors.  */
 139   result = handle_descr (ta, callback, cbdata_p, state, ti_pri, 0,
 140                          phc[0].h_descr);
 141   if (result != TD_OK)
 142     return result;
 143   result = handle_descr (ta, callback, cbdata_p, state, ti_pri, 1,
 144                          phc[1].h_descr);
 145   if (result != TD_OK)
 146     return result;
 147
 148   /* Read all the descriptors.  */
 149   if (ps_pdread (ta->ph, ta->handles + 2, &phc[2],
 150                  (sizeof (struct pthread_handle_struct)
 151                   * (pthread_threads_max - 2))) != PS_OK)
 152     return TD_ERR;      /* XXX Other error value?  */
 153
 154 #ifdef ALL_THREADS_STOPPED
 155   /* Read the number of currently active threads.  */
 156   if (ps_pdread (ta->ph, ta->pthread_handles_num, &num, sizeof (int)) != PS_OK)
 157     return TD_ERR;      /* XXX Other error value?  */
 158 #endif
 159
 160   /* Now get all descriptors, one after the other.  */
 161   for (cnt = 2; cnt < pthread_threads_max && num > 0; ++cnt)
 162     if (phc[cnt].h_descr != NULL)
 163       {
 164 #ifdef ALL_THREADS_STOPPED
 165         /* First count this active thread.  */
 166         --num;
 167 #endif
 168
 169         result = handle_descr (ta, callback, cbdata_p, state, ti_pri, cnt,
 170                                phc[cnt].h_descr);
 171         if (result != TD_OK)
 172           break;
 173       }
 174
 175   return result;
 176 }