nptl_db/td_ta_event_getmsg.c

   1 /* Retrieve event.
   2    Copyright (C) 1999, 2001, 2002 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 <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   /* XXX Use at least __thread once it is possible.  */
  32   static td_thrhandle_t th;
  33
  34   LOG ("td_ta_event_getmsg");
  35
  36   /* Test whether the TA parameter is ok.  */
  37   if (! ta_ok (ta))
  38     return TD_BADTA;
  39
  40   /* Get the pointer to the thread descriptor with the last event.  */
  41   psaddr_t addr;
  42   if (ps_pdread (ta->ph, ta->pthread_last_event,
  43                  &addr, sizeof (struct pthread *)) != PS_OK)
  44     return TD_ERR;      /* XXX Other error value?  */
  45
  46   if (addr == 0)
  47     /* Nothing waiting.  */
  48     return TD_NOMSG;
  49
  50   /* Read the event structure from the target.  */
  51   td_eventbuf_t event;
  52   if (ps_pdread (ta->ph, (char *) addr + offsetof (struct pthread, eventbuf),
  53                  &event, sizeof (td_eventbuf_t)) != PS_OK)
  54     return TD_ERR;      /* XXX Other error value?  */
  55
  56   /* If the structure is on the list there better be an event recorded.  */
  57   assert (event.eventnum != TD_EVENT_NONE);
  58
  59   /* Generate the thread descriptor.  */
  60   th.th_ta_p = (td_thragent_t *) ta;
  61   th.th_unique = addr;
  62
  63   /* Fill the user's data structure.  */
  64   msg->event = event.eventnum;
  65   msg->th_p = &th;
  66   msg->msg.data = (uintptr_t) event.eventdata;
  67
  68   /* Get the pointer to the next descriptor with an event.  */
  69   psaddr_t next;
  70   if (ps_pdread (ta->ph, (char *) addr + offsetof (struct pthread, nextevent),
  71                  &next, sizeof (struct pthread *)) != PS_OK)
  72     return TD_ERR;      /* XXX Other error value?  */
  73
  74   /* Store the pointer in the list head variable.  */
  75   if (ps_pdwrite (ta->ph, ta->pthread_last_event,
  76                   &next, sizeof (struct pthread *)) != PS_OK)
  77     return TD_ERR;      /* XXX Other error value?  */
  78
  79   /* Clear the next pointer in the current descriptor.  */
  80   next = NULL;
  81   if (ps_pdwrite (ta->ph, (char *) addr + offsetof (struct pthread, nextevent),
  82                   &next, sizeof (struct pthread *)) != PS_OK)
  83     return TD_ERR;      /* XXX Other error value?  */
  84
  85   return TD_OK;
  86 }