linuxthreads_db/td_ta_event_getmsg.c

   1 /* Retrieve event.
   2    Copyright (C) 1999 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 <stddef.h>
  22 #include <string.h>
  23
  24 #include "thread_dbP.h"
  25
  26
  27 td_err_e
  28 td_ta_event_getmsg (const td_thragent_t *ta, td_event_msg_t *msg)
  29 {
  30   /* XXX I cannot think of another way but using a static variable.  */
  31   static td_thrhandle_t th;
  32   td_eventbuf_t event;
  33   psaddr_t addr;
  34
  35   LOG (__FUNCTION__);
  36
  37   /* Test whether the TA parameter is ok.  */
  38   if (! ta_ok (ta))
  39     return TD_BADTA;
  40
  41   /* Get the pointer to the thread descriptor with the last event.  */
  42   if (ps_pdread (ta->ph, ta->pthread_last_event,
  43                  &addr, sizeof (void *)) != PS_OK)
  44     return TD_ERR;      /* XXX Other error value?  */
  45
  46   /* If the pointer is NULL no event occurred.  */
  47   if (addr == 0)
  48     return TD_NOMSG;
  49
  50   /* Read the even structure from the target.  */
  51   if (ps_pdread (ta->ph,
  52                  ((char *) addr
  53                   + offsetof (struct _pthread_descr_struct, p_eventbuf)),
  54                  &event, sizeof (td_eventbuf_t)) != PS_OK)
  55     return TD_ERR;      /* XXX Other error value?  */
  56
  57   /* Check whether an event occurred.  */
  58   if (event.eventnum == TD_EVENT_NONE)
  59     {
  60       /* Oh well, this means the last event was already read.  So
  61          we have to look for any other event.  */
  62       struct pthread_handle_struct handles[ta->pthread_threads_max];
  63       int num;
  64       int i;
  65
  66       /* Read the number of currently active threads.  */
  67       if (ps_pdread (ta->ph, ta->pthread_handles_num, &num, sizeof (int))
  68           != PS_OK)
  69         return TD_ERR;  /* XXX Other error value?  */
  70
  71       /* Now read the handles.  */
  72       if (ps_pdread (ta->ph, ta->handles, handles,
  73                      ta->pthread_threads_max * sizeof (handles[0])) != PS_OK)
  74         return TD_ERR;  /* XXX Other error value?  */
  75
  76       for (i = 0; i < ta->pthread_threads_max && num > 0; ++i)
  77         {
  78           if (handles[i].h_descr == NULL)
  79             /* No entry here.  */
  80             continue;
  81
  82           /* First count this active thread.  */
  83           --num;
  84
  85           if (handles[i].h_descr == addr)
  86             /* We already handled this.  */
  87             continue;
  88
  89           /* Read the event data for this thread.  */
  90           if (ps_pdread (ta->ph,
  91                          ((char *) handles[i].h_descr
  92                           + offsetof (struct _pthread_descr_struct,
  93                                       p_eventbuf)),
  94                          &event, sizeof (td_eventbuf_t)) != PS_OK)
  95             return TD_ERR;
  96
  97           if (event.eventnum != TD_EVENT_NONE)
  98             {
  99               /* We found a thread with an unreported event.  */
 100               addr = handles[i].h_descr;
 101               break;
 102             }
 103         }
 104
 105       /* If we haven't found any other event signal this to the user.  */
 106       if (event.eventnum == TD_EVENT_NONE)
 107         return TD_NOMSG;
 108     }
 109
 110   /* Generate the thread descriptor.  */
 111   th.th_ta_p = (td_thragent_t *) ta;
 112   th.th_unique = addr;
 113
 114   /* Fill the user's data structure.  */
 115   msg->event = event.eventnum;
 116   msg->th_p = &th;
 117   msg->msg.data = (uintptr_t) event.eventdata;
 118
 119   /* And clear the event message in the target.  */
 120   memset (&event, '\0', sizeof (td_eventbuf_t));
 121   if (ps_pdwrite (ta->ph,
 122                   ((char *) addr
 123                    + offsetof (struct _pthread_descr_struct, p_eventbuf)),
 124                   &event, sizeof (td_eventbuf_t)) != PS_OK)
 125     return TD_ERR;      /* XXX Other error value?  */
 126
 127   return TD_OK;
 128 }