1/* Get thread information.
2 Copyright (C) 1999-2021 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, see
18 <https://www.gnu.org/licenses/>. */
19
20#include <stddef.h>
21#include <string.h>
22#include <stdint.h>
23#include "thread_dbP.h"
24
25
26td_err_e
27td_thr_get_info (const td_thrhandle_t *th, td_thrinfo_t *infop)
28{
29 td_err_e err;
30 void *copy;
31 psaddr_t tls, schedpolicy, schedprio, cancelhandling, tid, report_events;
32
33 LOG ("td_thr_get_info");
34
35 if (th->th_unique == 0)
36 {
37 /* Special case for the main thread before initialization. */
38 copy = NULL;
39 tls = 0;
40 cancelhandling = 0;
41 schedpolicy = SCHED_OTHER;
42 schedprio = 0;
43 tid = 0;
44
45 /* Ignore errors to obtain the __nptl_initial_report_events
46 value because GDB no longer uses the events interface, and
47 other libthread_db consumers hopefully can handle different
48 libpthread/lds.o load orders. */
49 report_events = 0;
50 (void) DB_GET_VALUE (report_events, th->th_ta_p,
51 __nptl_initial_report_events, 0);
52 err = TD_OK;
53 }
54 else
55 {
56 /* Copy the whole descriptor in once so we can access the several
57 fields locally. Excess copying in one go is much better than
58 multiple ps_pdread calls. */
59 err = DB_GET_STRUCT (copy, th->th_ta_p, th->th_unique, pthread);
60 if (err != TD_OK)
61 return err;
62
63 err = DB_GET_FIELD_ADDRESS (tls, th->th_ta_p, th->th_unique,
64 pthread, specific, 0);
65 if (err != TD_OK)
66 return err;
67
68 err = DB_GET_FIELD_LOCAL (schedpolicy, th->th_ta_p, copy, pthread,
69 schedpolicy, 0);
70 if (err != TD_OK)
71 return err;
72 err = DB_GET_FIELD_LOCAL (schedprio, th->th_ta_p, copy, pthread,
73 schedparam_sched_priority, 0);
74 if (err != TD_OK)
75 return err;
76 err = DB_GET_FIELD_LOCAL (tid, th->th_ta_p, copy, pthread, tid, 0);
77 if (err != TD_OK)
78 return err;
79 err = DB_GET_FIELD_LOCAL (cancelhandling, th->th_ta_p, copy, pthread,
80 cancelhandling, 0);
81 if (err != TD_OK)
82 return err;
83 err = DB_GET_FIELD_LOCAL (report_events, th->th_ta_p, copy, pthread,
84 report_events, 0);
85 }
86 if (err != TD_OK)
87 return err;
88
89 /* Fill in information. Clear first to provide reproducable
90 results for the fields we do not fill in. */
91 memset (infop, '\0', sizeof (td_thrinfo_t));
92
93 infop->ti_tid = (thread_t) th->th_unique;
94 infop->ti_tls = (char *) tls;
95 infop->ti_pri = ((uintptr_t) schedpolicy == SCHED_OTHER
96 ? 0 : (uintptr_t) schedprio);
97 infop->ti_type = TD_THR_USER;
98
99 if ((((int) (uintptr_t) cancelhandling) & EXITING_BITMASK) == 0)
100 /* XXX For now there is no way to get more information. */
101 infop->ti_state = TD_THR_ACTIVE;
102 else if ((((int) (uintptr_t) cancelhandling) & TERMINATED_BITMASK) == 0)
103 infop->ti_state = TD_THR_ZOMBIE;
104 else
105 infop->ti_state = TD_THR_UNKNOWN;
106
107 /* Initialization which are the same in both cases. */
108 infop->ti_ta_p = th->th_ta_p;
109 infop->ti_lid = tid == 0 ? ps_getpid (th->th_ta_p->ph) : (uintptr_t) tid;
110 infop->ti_traceme = report_events != 0;
111
112 if (copy != NULL)
113 err = DB_GET_FIELD_LOCAL (infop->ti_startfunc, th->th_ta_p, copy, pthread,
114 start_routine, 0);
115 if (copy != NULL && err == TD_OK)
116 {
117 uint32_t idx;
118 for (idx = 0; idx < TD_EVENTSIZE; ++idx)
119 {
120 psaddr_t word;
121 err = DB_GET_FIELD_LOCAL (word, th->th_ta_p, copy, pthread,
122 eventbuf_eventmask_event_bits, idx);
123 if (err != TD_OK)
124 break;
125 infop->ti_events.event_bits[idx] = (uintptr_t) word;
126 }
127 if (err == TD_NOAPLIC)
128 memset (&infop->ti_events.event_bits[idx], 0,
129 (TD_EVENTSIZE - idx) * sizeof infop->ti_events.event_bits[0]);
130 }
131
132 return err;
133}
134