glibc/nptl_db/td_ta_event_getmsg.c

105 lines
3.2 KiB
C

/* Retrieve event.
Copyright (C) 1999-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 1999.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <stddef.h>
#include <string.h>
#include "thread_dbP.h"
td_err_e
td_ta_event_getmsg (const td_thragent_t *ta_arg, td_event_msg_t *msg)
{
td_thragent_t *const ta = (td_thragent_t *) ta_arg;
td_err_e err;
psaddr_t eventbuf, eventnum, eventdata;
psaddr_t thp, next;
void *copy;
/* XXX I cannot think of another way but using a static variable. */
/* XXX Use at least __thread once it is possible. */
static td_thrhandle_t th;
LOG ("td_thr_event_getmsg");
/* Test whether the TA parameter is ok. */
if (! ta_ok (ta))
return TD_BADTA;
/* Get the pointer to the thread descriptor with the last event. */
err = DB_GET_VALUE (thp, ta, __nptl_last_event, 0);
if (err != TD_OK)
return err;
if (thp == 0)
/* Nothing waiting. */
return TD_NOMSG;
/* Copy the event message buffer in from the inferior. */
err = DB_GET_FIELD_ADDRESS (eventbuf, ta, thp, pthread, eventbuf, 0);
if (err == TD_OK)
err = DB_GET_STRUCT (copy, ta, eventbuf, td_eventbuf_t);
if (err != TD_OK)
return err;
/* Read the event details from the target thread. */
err = DB_GET_FIELD_LOCAL (eventnum, ta, copy, td_eventbuf_t, eventnum, 0);
if (err != TD_OK)
return err;
/* If the structure is on the list there better be an event recorded. */
if ((int) (uintptr_t) eventnum == TD_EVENT_NONE)
return TD_DBERR;
/* Fill the user's data structure. */
err = DB_GET_FIELD_LOCAL (eventdata, ta, copy, td_eventbuf_t, eventdata, 0);
if (err != TD_OK)
return err;
/* Generate the thread descriptor. */
th.th_ta_p = (td_thragent_t *) ta;
th.th_unique = thp;
/* Fill the user's data structure. */
msg->msg.data = (uintptr_t) eventdata;
msg->event = (uintptr_t) eventnum;
msg->th_p = &th;
/* And clear the event message in the target. */
memset (copy, 0, ta->ta_sizeof_td_eventbuf_t);
err = DB_PUT_STRUCT (ta, eventbuf, td_eventbuf_t, copy);
if (err != TD_OK)
return err;
/* Get the pointer to the next descriptor with an event. */
err = DB_GET_FIELD (next, ta, thp, pthread, nextevent, 0);
if (err != TD_OK)
return err;
/* Store the pointer in the list head variable. */
err = DB_PUT_VALUE (ta, __nptl_last_event, 0, next);
if (err != TD_OK)
return err;
if (next != 0)
/* Clear the next pointer in the current descriptor. */
err = DB_PUT_FIELD (ta, thp, pthread, nextevent, 0, 0);
return err;
}