linuxthreads_db/td_ta_thr_iter.c

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