summaryrefslogtreecommitdiff
path: root/source/Plugins/StructuredData/DarwinLog/StructuredDataDarwinLog.cpp
blob: f5bf13036e40397c28c6b4c096562aabb52b5edb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
//===-- StructuredDataDarwinLog.cpp -----------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "StructuredDataDarwinLog.h"

// C includes
#include <string.h>

// C++ includes
#include <sstream>

#include "lldb/Breakpoint/StoppointCallbackContext.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandObjectMultiword.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/OptionArgParser.h"
#include "lldb/Interpreter/OptionValueProperties.h"
#include "lldb/Interpreter/OptionValueString.h"
#include "lldb/Interpreter/Property.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/ThreadPlanCallOnFunctionExit.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/RegularExpression.h"

#define DARWIN_LOG_TYPE_VALUE "DarwinLog"

using namespace lldb;
using namespace lldb_private;

#pragma mark -
#pragma mark Anonymous Namespace

// -----------------------------------------------------------------------------
// Anonymous namespace
// -----------------------------------------------------------------------------

namespace sddarwinlog_private {
const uint64_t NANOS_PER_MICRO = 1000;
const uint64_t NANOS_PER_MILLI = NANOS_PER_MICRO * 1000;
const uint64_t NANOS_PER_SECOND = NANOS_PER_MILLI * 1000;
const uint64_t NANOS_PER_MINUTE = NANOS_PER_SECOND * 60;
const uint64_t NANOS_PER_HOUR = NANOS_PER_MINUTE * 60;

static bool DEFAULT_FILTER_FALLTHROUGH_ACCEPTS = true;

//------------------------------------------------------------------
/// Global, sticky enable switch.  If true, the user has explicitly
/// run the enable command.  When a process launches or is attached to,
/// we will enable DarwinLog if either the settings for auto-enable is
/// on, or if the user had explicitly run enable at some point prior
/// to the launch/attach.
//------------------------------------------------------------------
static bool s_is_explicitly_enabled;

class EnableOptions;
using EnableOptionsSP = std::shared_ptr<EnableOptions>;

using OptionsMap =
    std::map<DebuggerWP, EnableOptionsSP, std::owner_less<DebuggerWP>>;

static OptionsMap &GetGlobalOptionsMap() {
  static OptionsMap s_options_map;
  return s_options_map;
}

static std::mutex &GetGlobalOptionsMapLock() {
  static std::mutex s_options_map_lock;
  return s_options_map_lock;
}

EnableOptionsSP GetGlobalEnableOptions(const DebuggerSP &debugger_sp) {
  if (!debugger_sp)
    return EnableOptionsSP();

  std::lock_guard<std::mutex> locker(GetGlobalOptionsMapLock());
  OptionsMap &options_map = GetGlobalOptionsMap();
  DebuggerWP debugger_wp(debugger_sp);
  auto find_it = options_map.find(debugger_wp);
  if (find_it != options_map.end())
    return find_it->second;
  else
    return EnableOptionsSP();
}

void SetGlobalEnableOptions(const DebuggerSP &debugger_sp,
                            const EnableOptionsSP &options_sp) {
  std::lock_guard<std::mutex> locker(GetGlobalOptionsMapLock());
  OptionsMap &options_map = GetGlobalOptionsMap();
  DebuggerWP debugger_wp(debugger_sp);
  auto find_it = options_map.find(debugger_wp);
  if (find_it != options_map.end())
    find_it->second = options_sp;
  else
    options_map.insert(std::make_pair(debugger_wp, options_sp));
}

#pragma mark -
#pragma mark Settings Handling

//------------------------------------------------------------------
/// Code to handle the StructuredDataDarwinLog settings
//------------------------------------------------------------------

static constexpr PropertyDefinition g_properties[] = {
    {
        "enable-on-startup",       // name
        OptionValue::eTypeBoolean, // type
        true,                      // global
        false,                     // default uint value
        nullptr,                   // default cstring value
        {},                        // enum values
        "Enable Darwin os_log collection when debugged process is launched "
        "or attached." // description
    },
    {
        "auto-enable-options",    // name
        OptionValue::eTypeString, // type
        true,                     // global
        0,                        // default uint value
        "",                       // default cstring value
        {},                       // enum values
        "Specify the options to 'plugin structured-data darwin-log enable' "
        "that should be applied when automatically enabling logging on "
        "startup/attach." // description
    }};

enum { ePropertyEnableOnStartup = 0, ePropertyAutoEnableOptions = 1 };

class StructuredDataDarwinLogProperties : public Properties {
public:
  static ConstString &GetSettingName() {
    static ConstString g_setting_name("darwin-log");
    return g_setting_name;
  }

  StructuredDataDarwinLogProperties() : Properties() {
    m_collection_sp.reset(new OptionValueProperties(GetSettingName()));
    m_collection_sp->Initialize(g_properties);
  }

  virtual ~StructuredDataDarwinLogProperties() {}

  bool GetEnableOnStartup() const {
    const uint32_t idx = ePropertyEnableOnStartup;
    return m_collection_sp->GetPropertyAtIndexAsBoolean(
        nullptr, idx, g_properties[idx].default_uint_value != 0);
  }

  llvm::StringRef GetAutoEnableOptions() const {
    const uint32_t idx = ePropertyAutoEnableOptions;
    return m_collection_sp->GetPropertyAtIndexAsString(
        nullptr, idx, g_properties[idx].default_cstr_value);
  }

  const char *GetLoggingModuleName() const { return "libsystem_trace.dylib"; }
};

using StructuredDataDarwinLogPropertiesSP =
    std::shared_ptr<StructuredDataDarwinLogProperties>;

static const StructuredDataDarwinLogPropertiesSP &GetGlobalProperties() {
  static StructuredDataDarwinLogPropertiesSP g_settings_sp;
  if (!g_settings_sp)
    g_settings_sp.reset(new StructuredDataDarwinLogProperties());
  return g_settings_sp;
}

const char *const s_filter_attributes[] = {
    "activity",       // current activity
    "activity-chain", // entire activity chain, each level separated by ':'
    "category",       // category of the log message
    "message",        // message contents, fully expanded
    "subsystem"       // subsystem of the log message

    // Consider implementing this action as it would be cheaper to filter.
    // "message" requires always formatting the message, which is a waste of
    // cycles if it ends up being rejected. "format",      // format string
    // used to format message text
};

static const ConstString &GetDarwinLogTypeName() {
  static const ConstString s_key_name("DarwinLog");
  return s_key_name;
}

static const ConstString &GetLogEventType() {
  static const ConstString s_event_type("log");
  return s_event_type;
}

class FilterRule;
using FilterRuleSP = std::shared_ptr<FilterRule>;

class FilterRule {
public:
  virtual ~FilterRule() {}

  using OperationCreationFunc =
      std::function<FilterRuleSP(bool accept, size_t attribute_index,
                                 const std::string &op_arg, Status &error)>;

  static void RegisterOperation(const ConstString &operation,
                                const OperationCreationFunc &creation_func) {
    GetCreationFuncMap().insert(std::make_pair(operation, creation_func));
  }

  static FilterRuleSP CreateRule(bool match_accepts, size_t attribute,
                                 const ConstString &operation,
                                 const std::string &op_arg, Status &error) {
    // Find the creation func for this type of filter rule.
    auto map = GetCreationFuncMap();
    auto find_it = map.find(operation);
    if (find_it == map.end()) {
      error.SetErrorStringWithFormat("unknown filter operation \""
                                     "%s\"",
                                     operation.GetCString());
      return FilterRuleSP();
    }

    return find_it->second(match_accepts, attribute, op_arg, error);
  }

  StructuredData::ObjectSP Serialize() const {
    StructuredData::Dictionary *dict_p = new StructuredData::Dictionary();

    // Indicate whether this is an accept or reject rule.
    dict_p->AddBooleanItem("accept", m_accept);

    // Indicate which attribute of the message this filter references. This can
    // drop into the rule-specific DoSerialization if we get to the point where
    // not all FilterRule derived classes work on an attribute.  (e.g. logical
    // and/or and other compound operations).
    dict_p->AddStringItem("attribute", s_filter_attributes[m_attribute_index]);

    // Indicate the type of the rule.
    dict_p->AddStringItem("type", GetOperationType().GetCString());

    // Let the rule add its own specific details here.
    DoSerialization(*dict_p);

    return StructuredData::ObjectSP(dict_p);
  }

  virtual void Dump(Stream &stream) const = 0;

  const ConstString &GetOperationType() const { return m_operation; }

protected:
  FilterRule(bool accept, size_t attribute_index, const ConstString &operation)
      : m_accept(accept), m_attribute_index(attribute_index),
        m_operation(operation) {}

  virtual void DoSerialization(StructuredData::Dictionary &dict) const = 0;

  bool GetMatchAccepts() const { return m_accept; }

  const char *GetFilterAttribute() const {
    return s_filter_attributes[m_attribute_index];
  }

private:
  using CreationFuncMap = std::map<ConstString, OperationCreationFunc>;

  static CreationFuncMap &GetCreationFuncMap() {
    static CreationFuncMap s_map;
    return s_map;
  }

  const bool m_accept;
  const size_t m_attribute_index;
  const ConstString m_operation;
};

using FilterRules = std::vector<FilterRuleSP>;

class RegexFilterRule : public FilterRule {
public:
  static void RegisterOperation() {
    FilterRule::RegisterOperation(StaticGetOperation(), CreateOperation);
  }

  void Dump(Stream &stream) const override {
    stream.Printf("%s %s regex %s", GetMatchAccepts() ? "accept" : "reject",
                  GetFilterAttribute(), m_regex_text.c_str());
  }

protected:
  void DoSerialization(StructuredData::Dictionary &dict) const override {
    dict.AddStringItem("regex", m_regex_text);
  }

private:
  static FilterRuleSP CreateOperation(bool accept, size_t attribute_index,
                                      const std::string &op_arg,
                                      Status &error) {
    // We treat the op_arg as a regex.  Validate it.
    if (op_arg.empty()) {
      error.SetErrorString("regex filter type requires a regex "
                           "argument");
      return FilterRuleSP();
    }

    // Instantiate the regex so we can report any errors.
    auto regex = RegularExpression(op_arg);
    if (!regex.IsValid()) {
      char error_text[256];
      error_text[0] = '\0';
      regex.GetErrorAsCString(error_text, sizeof(error_text));
      error.SetErrorString(error_text);
      return FilterRuleSP();
    }

    // We passed all our checks, this appears fine.
    error.Clear();
    return FilterRuleSP(new RegexFilterRule(accept, attribute_index, op_arg));
  }

  static const ConstString &StaticGetOperation() {
    static ConstString s_operation("regex");
    return s_operation;
  }

  RegexFilterRule(bool accept, size_t attribute_index,
                  const std::string &regex_text)
      : FilterRule(accept, attribute_index, StaticGetOperation()),
        m_regex_text(regex_text) {}

  const std::string m_regex_text;
};

class ExactMatchFilterRule : public FilterRule {
public:
  static void RegisterOperation() {
    FilterRule::RegisterOperation(StaticGetOperation(), CreateOperation);
  }

  void Dump(Stream &stream) const override {
    stream.Printf("%s %s match %s", GetMatchAccepts() ? "accept" : "reject",
                  GetFilterAttribute(), m_match_text.c_str());
  }

protected:
  void DoSerialization(StructuredData::Dictionary &dict) const override {
    dict.AddStringItem("exact_text", m_match_text);
  }

private:
  static FilterRuleSP CreateOperation(bool accept, size_t attribute_index,
                                      const std::string &op_arg,
                                      Status &error) {
    if (op_arg.empty()) {
      error.SetErrorString("exact match filter type requires an "
                           "argument containing the text that must "
                           "match the specified message attribute.");
      return FilterRuleSP();
    }

    error.Clear();
    return FilterRuleSP(
        new ExactMatchFilterRule(accept, attribute_index, op_arg));
  }

  static const ConstString &StaticGetOperation() {
    static ConstString s_operation("match");
    return s_operation;
  }

  ExactMatchFilterRule(bool accept, size_t attribute_index,
                       const std::string &match_text)
      : FilterRule(accept, attribute_index, StaticGetOperation()),
        m_match_text(match_text) {}

  const std::string m_match_text;
};

static void RegisterFilterOperations() {
  ExactMatchFilterRule::RegisterOperation();
  RegexFilterRule::RegisterOperation();
}

// =========================================================================
// Commands
// =========================================================================

// -------------------------------------------------------------------------
/// Provides the main on-off switch for enabling darwin logging.
///
/// It is valid to run the enable command when logging is already enabled.
/// This resets the logging with whatever settings are currently set.
// -------------------------------------------------------------------------

static constexpr OptionDefinition g_enable_option_table[] = {
    // Source stream include/exclude options (the first-level filter). This one
    // should be made as small as possible as everything that goes through here
    // must be processed by the process monitor.
    {LLDB_OPT_SET_ALL, false, "any-process", 'a', OptionParser::eNoArgument,
     nullptr, {}, 0, eArgTypeNone,
     "Specifies log messages from other related processes should be "
     "included."},
    {LLDB_OPT_SET_ALL, false, "debug", 'd', OptionParser::eNoArgument, nullptr,
     {}, 0, eArgTypeNone,
     "Specifies debug-level log messages should be included.  Specifying"
     " --debug implies --info."},
    {LLDB_OPT_SET_ALL, false, "info", 'i', OptionParser::eNoArgument, nullptr,
     {}, 0, eArgTypeNone,
     "Specifies info-level log messages should be included."},
    {LLDB_OPT_SET_ALL, false, "filter", 'f', OptionParser::eRequiredArgument,
     nullptr, {}, 0, eArgRawInput,
     // There doesn't appear to be a great way for me to have these multi-line,
     // formatted tables in help.  This looks mostly right but there are extra
     // linefeeds added at seemingly random spots, and indentation isn't
     // handled properly on those lines.
     "Appends a filter rule to the log message filter chain.  Multiple "
     "rules may be added by specifying this option multiple times, "
     "once per filter rule.  Filter rules are processed in the order "
     "they are specified, with the --no-match-accepts setting used "
     "for any message that doesn't match one of the rules.\n"
     "\n"
     "    Filter spec format:\n"
     "\n"
     "    --filter \"{action} {attribute} {op}\"\n"
     "\n"
     "    {action} :=\n"
     "      accept |\n"
     "      reject\n"
     "\n"
     "    {attribute} :=\n"
     "       activity       |  // message's most-derived activity\n"
     "       activity-chain |  // message's {parent}:{child} activity\n"
     "       category       |  // message's category\n"
     "       message        |  // message's expanded contents\n"
     "       subsystem      |  // message's subsystem\n"
     "\n"
     "    {op} :=\n"
     "      match {exact-match-text} |\n"
     "      regex {search-regex}\n"
     "\n"
     "The regex flavor used is the C++ std::regex ECMAScript format.  "
     "Prefer character classes like [[:digit:]] to \\d and the like, as "
     "getting the backslashes escaped through properly is error-prone."},
    {LLDB_OPT_SET_ALL, false, "live-stream", 'l',
     OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean,
     "Specify whether logging events are live-streamed or buffered.  "
     "True indicates live streaming, false indicates buffered.  The "
     "default is true (live streaming).  Live streaming will deliver "
     "log messages with less delay, but buffered capture mode has less "
     "of an observer effect."},
    {LLDB_OPT_SET_ALL, false, "no-match-accepts", 'n',
     OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean,
     "Specify whether a log message that doesn't match any filter rule "
     "is accepted or rejected, where true indicates accept.  The "
     "default is true."},
    {LLDB_OPT_SET_ALL, false, "echo-to-stderr", 'e',
     OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean,
     "Specify whether os_log()/NSLog() messages are echoed to the "
     "target program's stderr.  When DarwinLog is enabled, we shut off "
     "the mirroring of os_log()/NSLog() to the program's stderr.  "
     "Setting this flag to true will restore the stderr mirroring."
     "The default is false."},
    {LLDB_OPT_SET_ALL, false, "broadcast-events", 'b',
     OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean,
     "Specify if the plugin should broadcast events.  Broadcasting "
     "log events is a requirement for displaying the log entries in "
     "LLDB command-line.  It is also required if LLDB clients want to "
     "process log events.  The default is true."},
    // Message formatting options
    {LLDB_OPT_SET_ALL, false, "timestamp-relative", 'r',
     OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone,
     "Include timestamp in the message header when printing a log "
     "message.  The timestamp is relative to the first displayed "
     "message."},
    {LLDB_OPT_SET_ALL, false, "subsystem", 's', OptionParser::eNoArgument,
     nullptr, {}, 0, eArgTypeNone,
     "Include the subsystem in the message header when displaying "
     "a log message."},
    {LLDB_OPT_SET_ALL, false, "category", 'c', OptionParser::eNoArgument,
     nullptr, {}, 0, eArgTypeNone,
     "Include the category in the message header when displaying "
     "a log message."},
    {LLDB_OPT_SET_ALL, false, "activity-chain", 'C', OptionParser::eNoArgument,
     nullptr, {}, 0, eArgTypeNone,
     "Include the activity parent-child chain in the message header "
     "when displaying a log message.  The activity hierarchy is "
     "displayed as {grandparent-activity}:"
     "{parent-activity}:{activity}[:...]."},
    {LLDB_OPT_SET_ALL, false, "all-fields", 'A', OptionParser::eNoArgument,
     nullptr, {}, 0, eArgTypeNone,
     "Shortcut to specify that all header fields should be displayed."}};

class EnableOptions : public Options {
public:
  EnableOptions()
      : Options(), m_include_debug_level(false), m_include_info_level(false),
        m_include_any_process(false),
        m_filter_fall_through_accepts(DEFAULT_FILTER_FALLTHROUGH_ACCEPTS),
        m_echo_to_stderr(false), m_display_timestamp_relative(false),
        m_display_subsystem(false), m_display_category(false),
        m_display_activity_chain(false), m_broadcast_events(true),
        m_live_stream(true), m_filter_rules() {}

  void OptionParsingStarting(ExecutionContext *execution_context) override {
    m_include_debug_level = false;
    m_include_info_level = false;
    m_include_any_process = false;
    m_filter_fall_through_accepts = DEFAULT_FILTER_FALLTHROUGH_ACCEPTS;
    m_echo_to_stderr = false;
    m_display_timestamp_relative = false;
    m_display_subsystem = false;
    m_display_category = false;
    m_display_activity_chain = false;
    m_broadcast_events = true;
    m_live_stream = true;
    m_filter_rules.clear();
  }

  Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                        ExecutionContext *execution_context) override {
    Status error;

    const int short_option = m_getopt_table[option_idx].val;
    switch (short_option) {
    case 'a':
      m_include_any_process = true;
      break;

    case 'A':
      m_display_timestamp_relative = true;
      m_display_category = true;
      m_display_subsystem = true;
      m_display_activity_chain = true;
      break;

    case 'b':
      m_broadcast_events =
          OptionArgParser::ToBoolean(option_arg, true, nullptr);
      break;

    case 'c':
      m_display_category = true;
      break;

    case 'C':
      m_display_activity_chain = true;
      break;

    case 'd':
      m_include_debug_level = true;
      break;

    case 'e':
      m_echo_to_stderr = OptionArgParser::ToBoolean(option_arg, false, nullptr);
      break;

    case 'f':
      return ParseFilterRule(option_arg);

    case 'i':
      m_include_info_level = true;
      break;

    case 'l':
      m_live_stream = OptionArgParser::ToBoolean(option_arg, false, nullptr);
      break;

    case 'n':
      m_filter_fall_through_accepts =
          OptionArgParser::ToBoolean(option_arg, true, nullptr);
      break;

    case 'r':
      m_display_timestamp_relative = true;
      break;

    case 's':
      m_display_subsystem = true;
      break;

    default:
      error.SetErrorStringWithFormat("unsupported option '%c'", short_option);
    }
    return error;
  }

  llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
    return llvm::makeArrayRef(g_enable_option_table);
  }

  StructuredData::DictionarySP BuildConfigurationData(bool enabled) {
    StructuredData::DictionarySP config_sp(new StructuredData::Dictionary());

    // Set the basic enabled state.
    config_sp->AddBooleanItem("enabled", enabled);

    // If we're disabled, there's nothing more to add.
    if (!enabled)
      return config_sp;

    // Handle source stream flags.
    auto source_flags_sp =
        StructuredData::DictionarySP(new StructuredData::Dictionary());
    config_sp->AddItem("source-flags", source_flags_sp);

    source_flags_sp->AddBooleanItem("any-process", m_include_any_process);
    source_flags_sp->AddBooleanItem("debug-level", m_include_debug_level);
    // The debug-level flag, if set, implies info-level.
    source_flags_sp->AddBooleanItem("info-level", m_include_info_level ||
                                                      m_include_debug_level);
    source_flags_sp->AddBooleanItem("live-stream", m_live_stream);

    // Specify default filter rule (the fall-through)
    config_sp->AddBooleanItem("filter-fall-through-accepts",
                              m_filter_fall_through_accepts);

    // Handle filter rules
    if (!m_filter_rules.empty()) {
      auto json_filter_rules_sp =
          StructuredData::ArraySP(new StructuredData::Array);
      config_sp->AddItem("filter-rules", json_filter_rules_sp);
      for (auto &rule_sp : m_filter_rules) {
        if (!rule_sp)
          continue;
        json_filter_rules_sp->AddItem(rule_sp->Serialize());
      }
    }
    return config_sp;
  }

  bool GetIncludeDebugLevel() const { return m_include_debug_level; }

  bool GetIncludeInfoLevel() const {
    // Specifying debug level implies info level.
    return m_include_info_level || m_include_debug_level;
  }

  const FilterRules &GetFilterRules() const { return m_filter_rules; }

  bool GetFallthroughAccepts() const { return m_filter_fall_through_accepts; }

  bool GetEchoToStdErr() const { return m_echo_to_stderr; }

  bool GetDisplayTimestampRelative() const {
    return m_display_timestamp_relative;
  }

  bool GetDisplaySubsystem() const { return m_display_subsystem; }
  bool GetDisplayCategory() const { return m_display_category; }
  bool GetDisplayActivityChain() const { return m_display_activity_chain; }

  bool GetDisplayAnyHeaderFields() const {
    return m_display_timestamp_relative || m_display_activity_chain ||
           m_display_subsystem || m_display_category;
  }

  bool GetBroadcastEvents() const { return m_broadcast_events; }

private:
  Status ParseFilterRule(llvm::StringRef rule_text) {
    Status error;

    if (rule_text.empty()) {
      error.SetErrorString("invalid rule_text");
      return error;
    }

    // filter spec format:
    //
    // {action} {attribute} {op}
    //
    // {action} :=
    //   accept |
    //   reject
    //
    // {attribute} :=
    //   category       |
    //   subsystem      |
    //   activity       |
    //   activity-chain |
    //   message        |
    //   format
    //
    // {op} :=
    //   match {exact-match-text} |
    //   regex {search-regex}

    // Parse action.
    auto action_end_pos = rule_text.find(" ");
    if (action_end_pos == std::string::npos) {
      error.SetErrorStringWithFormat("could not parse filter rule "
                                     "action from \"%s\"",
                                     rule_text.str().c_str());
      return error;
    }
    auto action = rule_text.substr(0, action_end_pos);
    bool accept;
    if (action == "accept")
      accept = true;
    else if (action == "reject")
      accept = false;
    else {
      error.SetErrorString("filter action must be \"accept\" or \"deny\"");
      return error;
    }

    // parse attribute
    auto attribute_end_pos = rule_text.find(" ", action_end_pos + 1);
    if (attribute_end_pos == std::string::npos) {
      error.SetErrorStringWithFormat("could not parse filter rule "
                                     "attribute from \"%s\"",
                                     rule_text.str().c_str());
      return error;
    }
    auto attribute = rule_text.substr(action_end_pos + 1,
                                      attribute_end_pos - (action_end_pos + 1));
    auto attribute_index = MatchAttributeIndex(attribute);
    if (attribute_index < 0) {
      error.SetErrorStringWithFormat("filter rule attribute unknown: "
                                     "%s",
                                     attribute.str().c_str());
      return error;
    }

    // parse operation
    auto operation_end_pos = rule_text.find(" ", attribute_end_pos + 1);
    auto operation = rule_text.substr(
        attribute_end_pos + 1, operation_end_pos - (attribute_end_pos + 1));

    // add filter spec
    auto rule_sp =
        FilterRule::CreateRule(accept, attribute_index, ConstString(operation),
                               rule_text.substr(operation_end_pos + 1), error);

    if (rule_sp && error.Success())
      m_filter_rules.push_back(rule_sp);

    return error;
  }

  int MatchAttributeIndex(llvm::StringRef attribute_name) const {
    for (const auto &Item : llvm::enumerate(s_filter_attributes)) {
      if (attribute_name == Item.value())
        return Item.index();
    }

    // We didn't match anything.
    return -1;
  }

  bool m_include_debug_level;
  bool m_include_info_level;
  bool m_include_any_process;
  bool m_filter_fall_through_accepts;
  bool m_echo_to_stderr;
  bool m_display_timestamp_relative;
  bool m_display_subsystem;
  bool m_display_category;
  bool m_display_activity_chain;
  bool m_broadcast_events;
  bool m_live_stream;
  FilterRules m_filter_rules;
};

class EnableCommand : public CommandObjectParsed {
public:
  EnableCommand(CommandInterpreter &interpreter, bool enable, const char *name,
                const char *help, const char *syntax)
      : CommandObjectParsed(interpreter, name, help, syntax), m_enable(enable),
        m_options_sp(enable ? new EnableOptions() : nullptr) {}

protected:
  void AppendStrictSourcesWarning(CommandReturnObject &result,
                                  const char *source_name) {
    if (!source_name)
      return;

    // Check if we're *not* using strict sources.  If not, then the user is
    // going to get debug-level info anyways, probably not what they're
    // expecting. Unfortunately we can only fix this by adding an env var,
    // which would have had to have happened already.  Thus, a warning is the
    // best we can do here.
    StreamString stream;
    stream.Printf("darwin-log source settings specify to exclude "
                  "%s messages, but setting "
                  "'plugin.structured-data.darwin-log."
                  "strict-sources' is disabled.  This process will "
                  "automatically have %s messages included.  Enable"
                  " the property and relaunch the target binary to have"
                  " these messages excluded.",
                  source_name, source_name);
    result.AppendWarning(stream.GetString());
  }

  bool DoExecute(Args &command, CommandReturnObject &result) override {
    // First off, set the global sticky state of enable/disable based on this
    // command execution.
    s_is_explicitly_enabled = m_enable;

    // Next, if this is an enable, save off the option data. We will need it
    // later if a process hasn't been launched or attached yet.
    if (m_enable) {
      // Save off enabled configuration so we can apply these parsed options
      // the next time an attach or launch occurs.
      DebuggerSP debugger_sp =
          GetCommandInterpreter().GetDebugger().shared_from_this();
      SetGlobalEnableOptions(debugger_sp, m_options_sp);
    }

    // Now check if we have a running process.  If so, we should instruct the
    // process monitor to enable/disable DarwinLog support now.
    Target *target = GetSelectedOrDummyTarget();
    if (!target) {
      // No target, so there is nothing more to do right now.
      result.SetStatus(eReturnStatusSuccessFinishNoResult);
      return true;
    }

    // Grab the active process.
    auto process_sp = target->GetProcessSP();
    if (!process_sp) {
      // No active process, so there is nothing more to do right now.
      result.SetStatus(eReturnStatusSuccessFinishNoResult);
      return true;
    }

    // If the process is no longer alive, we can't do this now. We'll catch it
    // the next time the process is started up.
    if (!process_sp->IsAlive()) {
      result.SetStatus(eReturnStatusSuccessFinishNoResult);
      return true;
    }

    // Get the plugin for the process.
    auto plugin_sp =
        process_sp->GetStructuredDataPlugin(GetDarwinLogTypeName());
    if (!plugin_sp || (plugin_sp->GetPluginName() !=
                       StructuredDataDarwinLog::GetStaticPluginName())) {
      result.AppendError("failed to get StructuredDataPlugin for "
                         "the process");
      result.SetStatus(eReturnStatusFailed);
    }
    StructuredDataDarwinLog &plugin =
        *static_cast<StructuredDataDarwinLog *>(plugin_sp.get());

    if (m_enable) {
      // Hook up the breakpoint for the process that detects when libtrace has
      // been sufficiently initialized to really start the os_log stream.  This
      // is insurance to assure us that logging is really enabled.  Requesting
      // that logging be enabled for a process before libtrace is initialized
      // results in a scenario where no errors occur, but no logging is
      // captured, either.  This step is to eliminate that possibility.
      plugin.AddInitCompletionHook(*process_sp.get());
    }

    // Send configuration to the feature by way of the process. Construct the
    // options we will use.
    auto config_sp = m_options_sp->BuildConfigurationData(m_enable);
    const Status error =
        process_sp->ConfigureStructuredData(GetDarwinLogTypeName(), config_sp);

    // Report results.
    if (!error.Success()) {
      result.AppendError(error.AsCString());
      result.SetStatus(eReturnStatusFailed);
      // Our configuration failed, so we're definitely disabled.
      plugin.SetEnabled(false);
    } else {
      result.SetStatus(eReturnStatusSuccessFinishNoResult);
      // Our configuration succeeded, so we're enabled/disabled per whichever
      // one this command is setup to do.
      plugin.SetEnabled(m_enable);
    }
    return result.Succeeded();
  }

  Options *GetOptions() override {
    // We don't have options when this represents disable.
    return m_enable ? m_options_sp.get() : nullptr;
  }

private:
  const bool m_enable;
  EnableOptionsSP m_options_sp;
};

// -------------------------------------------------------------------------
/// Provides the status command.
// -------------------------------------------------------------------------
class StatusCommand : public CommandObjectParsed {
public:
  StatusCommand(CommandInterpreter &interpreter)
      : CommandObjectParsed(interpreter, "status",
                            "Show whether Darwin log supported is available"
                            " and enabled.",
                            "plugin structured-data darwin-log status") {}

protected:
  bool DoExecute(Args &command, CommandReturnObject &result) override {
    auto &stream = result.GetOutputStream();

    // Figure out if we've got a process.  If so, we can tell if DarwinLog is
    // available for that process.
    Target *target = GetSelectedOrDummyTarget();
    auto process_sp = target ? target->GetProcessSP() : ProcessSP();
    if (!target || !process_sp) {
      stream.PutCString("Availability: unknown (requires process)\n");
      stream.PutCString("Enabled: not applicable "
                        "(requires process)\n");
    } else {
      auto plugin_sp =
          process_sp->GetStructuredDataPlugin(GetDarwinLogTypeName());
      stream.Printf("Availability: %s\n",
                    plugin_sp ? "available" : "unavailable");
      auto &plugin_name = StructuredDataDarwinLog::GetStaticPluginName();
      const bool enabled =
          plugin_sp ? plugin_sp->GetEnabled(plugin_name) : false;
      stream.Printf("Enabled: %s\n", enabled ? "true" : "false");
    }

    // Display filter settings.
    DebuggerSP debugger_sp =
        GetCommandInterpreter().GetDebugger().shared_from_this();
    auto options_sp = GetGlobalEnableOptions(debugger_sp);
    if (!options_sp) {
      // Nothing more to do.
      result.SetStatus(eReturnStatusSuccessFinishResult);
      return true;
    }

    // Print filter rules
    stream.PutCString("DarwinLog filter rules:\n");

    stream.IndentMore();

    if (options_sp->GetFilterRules().empty()) {
      stream.Indent();
      stream.PutCString("none\n");
    } else {
      // Print each of the filter rules.
      int rule_number = 0;
      for (auto rule_sp : options_sp->GetFilterRules()) {
        ++rule_number;
        if (!rule_sp)
          continue;

        stream.Indent();
        stream.Printf("%02d: ", rule_number);
        rule_sp->Dump(stream);
        stream.PutChar('\n');
      }
    }
    stream.IndentLess();

    // Print no-match handling.
    stream.Indent();
    stream.Printf("no-match behavior: %s\n",
                  options_sp->GetFallthroughAccepts() ? "accept" : "reject");

    result.SetStatus(eReturnStatusSuccessFinishResult);
    return true;
  }
};

// -------------------------------------------------------------------------
/// Provides the darwin-log base command
// -------------------------------------------------------------------------
class BaseCommand : public CommandObjectMultiword {
public:
  BaseCommand(CommandInterpreter &interpreter)
      : CommandObjectMultiword(interpreter, "plugin structured-data darwin-log",
                               "Commands for configuring Darwin os_log "
                               "support.",
                               "") {
    // enable
    auto enable_help = "Enable Darwin log collection, or re-enable "
                       "with modified configuration.";
    auto enable_syntax = "plugin structured-data darwin-log enable";
    auto enable_cmd_sp = CommandObjectSP(
        new EnableCommand(interpreter,
                          true, // enable
                          "enable", enable_help, enable_syntax));
    LoadSubCommand("enable", enable_cmd_sp);

    // disable
    auto disable_help = "Disable Darwin log collection.";
    auto disable_syntax = "plugin structured-data darwin-log disable";
    auto disable_cmd_sp = CommandObjectSP(
        new EnableCommand(interpreter,
                          false, // disable
                          "disable", disable_help, disable_syntax));
    LoadSubCommand("disable", disable_cmd_sp);

    // status
    auto status_cmd_sp = CommandObjectSP(new StatusCommand(interpreter));
    LoadSubCommand("status", status_cmd_sp);
  }
};

EnableOptionsSP ParseAutoEnableOptions(Status &error, Debugger &debugger) {
  Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS);
  // We are abusing the options data model here so that we can parse options
  // without requiring the Debugger instance.

  // We have an empty execution context at this point.  We only want to parse
  // options, and we don't need any context to do this here. In fact, we want
  // to be able to parse the enable options before having any context.
  ExecutionContext exe_ctx;

  EnableOptionsSP options_sp(new EnableOptions());
  options_sp->NotifyOptionParsingStarting(&exe_ctx);

  CommandReturnObject result;

  // Parse the arguments.
  auto options_property_sp =
      debugger.GetPropertyValue(nullptr, "plugin.structured-data.darwin-log."
                                         "auto-enable-options",
                                false, error);
  if (!error.Success())
    return EnableOptionsSP();
  if (!options_property_sp) {
    error.SetErrorString("failed to find option setting for "
                         "plugin.structured-data.darwin-log.");
    return EnableOptionsSP();
  }

  const char *enable_options =
      options_property_sp->GetAsString()->GetCurrentValue();
  Args args(enable_options);
  if (args.GetArgumentCount() > 0) {
    // Eliminate the initial '--' that would be required to set the settings
    // that themselves include '-' and/or '--'.
    const char *first_arg = args.GetArgumentAtIndex(0);
    if (first_arg && (strcmp(first_arg, "--") == 0))
      args.Shift();
  }

  bool require_validation = false;
  llvm::Expected<Args> args_or =
      options_sp->Parse(args, &exe_ctx, PlatformSP(), require_validation);
  if (!args_or) {
    LLDB_LOG_ERROR(
        log, args_or.takeError(),
        "Parsing plugin.structured-data.darwin-log.auto-enable-options value "
        "failed: {0}");
    return EnableOptionsSP();
  }

  if (!options_sp->VerifyOptions(result))
    return EnableOptionsSP();

  // We successfully parsed and validated the options.
  return options_sp;
}

bool RunEnableCommand(CommandInterpreter &interpreter) {
  StreamString command_stream;

  command_stream << "plugin structured-data darwin-log enable";
  auto enable_options = GetGlobalProperties()->GetAutoEnableOptions();
  if (!enable_options.empty()) {
    command_stream << ' ';
    command_stream << enable_options;
  }

  // Run the command.
  CommandReturnObject return_object;
  interpreter.HandleCommand(command_stream.GetData(), eLazyBoolNo,
                            return_object);
  return return_object.Succeeded();
}
}
using namespace sddarwinlog_private;

#pragma mark -
#pragma mark Public static API

// -----------------------------------------------------------------------------
// Public static API
// -----------------------------------------------------------------------------

void StructuredDataDarwinLog::Initialize() {
  RegisterFilterOperations();
  PluginManager::RegisterPlugin(
      GetStaticPluginName(), "Darwin os_log() and os_activity() support",
      &CreateInstance, &DebuggerInitialize, &FilterLaunchInfo);
}

void StructuredDataDarwinLog::Terminate() {
  PluginManager::UnregisterPlugin(&CreateInstance);
}

const ConstString &StructuredDataDarwinLog::GetStaticPluginName() {
  static ConstString s_plugin_name("darwin-log");
  return s_plugin_name;
}

#pragma mark -
#pragma mark PluginInterface API

// -----------------------------------------------------------------------------
// PluginInterface API
// -----------------------------------------------------------------------------

ConstString StructuredDataDarwinLog::GetPluginName() {
  return GetStaticPluginName();
}

uint32_t StructuredDataDarwinLog::GetPluginVersion() { return 1; }

#pragma mark -
#pragma mark StructuredDataPlugin API

// -----------------------------------------------------------------------------
// StructuredDataPlugin API
// -----------------------------------------------------------------------------

bool StructuredDataDarwinLog::SupportsStructuredDataType(
    const ConstString &type_name) {
  return type_name == GetDarwinLogTypeName();
}

void StructuredDataDarwinLog::HandleArrivalOfStructuredData(
    Process &process, const ConstString &type_name,
    const StructuredData::ObjectSP &object_sp) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
  if (log) {
    StreamString json_stream;
    if (object_sp)
      object_sp->Dump(json_stream);
    else
      json_stream.PutCString("<null>");
    log->Printf("StructuredDataDarwinLog::%s() called with json: %s",
                __FUNCTION__, json_stream.GetData());
  }

  // Ignore empty structured data.
  if (!object_sp) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() StructuredData object "
                  "is null",
                  __FUNCTION__);
    return;
  }

  // Ignore any data that isn't for us.
  if (type_name != GetDarwinLogTypeName()) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() StructuredData type "
                  "expected to be %s but was %s, ignoring",
                  __FUNCTION__, GetDarwinLogTypeName().AsCString(),
                  type_name.AsCString());
    return;
  }

  // Broadcast the structured data event if we have that enabled. This is the
  // way that the outside world (all clients) get access to this data.  This
  // plugin sets policy as to whether we do that.
  DebuggerSP debugger_sp = process.GetTarget().GetDebugger().shared_from_this();
  auto options_sp = GetGlobalEnableOptions(debugger_sp);
  if (options_sp && options_sp->GetBroadcastEvents()) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() broadcasting event",
                  __FUNCTION__);
    process.BroadcastStructuredData(object_sp, shared_from_this());
  }

  // Later, hang on to a configurable amount of these and allow commands to
  // inspect, including showing backtraces.
}

static void SetErrorWithJSON(Status &error, const char *message,
                             StructuredData::Object &object) {
  if (!message) {
    error.SetErrorString("Internal error: message not set.");
    return;
  }

  StreamString object_stream;
  object.Dump(object_stream);
  object_stream.Flush();

  error.SetErrorStringWithFormat("%s: %s", message, object_stream.GetData());
}

Status StructuredDataDarwinLog::GetDescription(
    const StructuredData::ObjectSP &object_sp, lldb_private::Stream &stream) {
  Status error;

  if (!object_sp) {
    error.SetErrorString("No structured data.");
    return error;
  }

  // Log message payload objects will be dictionaries.
  const StructuredData::Dictionary *dictionary = object_sp->GetAsDictionary();
  if (!dictionary) {
    SetErrorWithJSON(error, "Structured data should have been a dictionary "
                            "but wasn't",
                     *object_sp);
    return error;
  }

  // Validate this is really a message for our plugin.
  ConstString type_name;
  if (!dictionary->GetValueForKeyAsString("type", type_name)) {
    SetErrorWithJSON(error, "Structured data doesn't contain mandatory "
                            "type field",
                     *object_sp);
    return error;
  }

  if (type_name != GetDarwinLogTypeName()) {
    // This is okay - it simply means the data we received is not a log
    // message.  We'll just format it as is.
    object_sp->Dump(stream);
    return error;
  }

  // DarwinLog dictionaries store their data
  // in an array with key name "events".
  StructuredData::Array *events = nullptr;
  if (!dictionary->GetValueForKeyAsArray("events", events) || !events) {
    SetErrorWithJSON(error, "Log structured data is missing mandatory "
                            "'events' field, expected to be an array",
                     *object_sp);
    return error;
  }

  events->ForEach(
      [&stream, &error, &object_sp, this](StructuredData::Object *object) {
        if (!object) {
          // Invalid.  Stop iterating.
          SetErrorWithJSON(error, "Log event entry is null", *object_sp);
          return false;
        }

        auto event = object->GetAsDictionary();
        if (!event) {
          // Invalid, stop iterating.
          SetErrorWithJSON(error, "Log event is not a dictionary", *object_sp);
          return false;
        }

        // If we haven't already grabbed the first timestamp value, do that
        // now.
        if (!m_recorded_first_timestamp) {
          uint64_t timestamp = 0;
          if (event->GetValueForKeyAsInteger("timestamp", timestamp)) {
            m_first_timestamp_seen = timestamp;
            m_recorded_first_timestamp = true;
          }
        }

        HandleDisplayOfEvent(*event, stream);
        return true;
      });

  stream.Flush();
  return error;
}

bool StructuredDataDarwinLog::GetEnabled(const ConstString &type_name) const {
  if (type_name == GetStaticPluginName())
    return m_is_enabled;
  else
    return false;
}

void StructuredDataDarwinLog::SetEnabled(bool enabled) {
  m_is_enabled = enabled;
}

void StructuredDataDarwinLog::ModulesDidLoad(Process &process,
                                             ModuleList &module_list) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
  if (log)
    log->Printf("StructuredDataDarwinLog::%s called (process uid %u)",
                __FUNCTION__, process.GetUniqueID());

  // Check if we should enable the darwin log support on startup/attach.
  if (!GetGlobalProperties()->GetEnableOnStartup() &&
      !s_is_explicitly_enabled) {
    // We're neither auto-enabled or explicitly enabled, so we shouldn't try to
    // enable here.
    if (log)
      log->Printf("StructuredDataDarwinLog::%s not applicable, we're not "
                  "enabled (process uid %u)",
                  __FUNCTION__, process.GetUniqueID());
    return;
  }

  // If we already added the breakpoint, we've got nothing left to do.
  {
    std::lock_guard<std::mutex> locker(m_added_breakpoint_mutex);
    if (m_added_breakpoint) {
      if (log)
        log->Printf("StructuredDataDarwinLog::%s process uid %u's "
                    "post-libtrace-init breakpoint is already set",
                    __FUNCTION__, process.GetUniqueID());
      return;
    }
  }

  // The logging support module name, specifies the name of the image name that
  // must be loaded into the debugged process before we can try to enable
  // logging.
  const char *logging_module_cstr =
      GetGlobalProperties()->GetLoggingModuleName();
  if (!logging_module_cstr || (logging_module_cstr[0] == 0)) {
    // We need this.  Bail.
    if (log)
      log->Printf("StructuredDataDarwinLog::%s no logging module name "
                  "specified, we don't know where to set a breakpoint "
                  "(process uid %u)",
                  __FUNCTION__, process.GetUniqueID());
    return;
  }

  const ConstString logging_module_name = ConstString(logging_module_cstr);

  // We need to see libtrace in the list of modules before we can enable
  // tracing for the target process.
  bool found_logging_support_module = false;
  for (size_t i = 0; i < module_list.GetSize(); ++i) {
    auto module_sp = module_list.GetModuleAtIndex(i);
    if (!module_sp)
      continue;

    auto &file_spec = module_sp->GetFileSpec();
    found_logging_support_module =
        (file_spec.GetLastPathComponent() == logging_module_name);
    if (found_logging_support_module)
      break;
  }

  if (!found_logging_support_module) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s logging module %s "
                  "has not yet been loaded, can't set a breakpoint "
                  "yet (process uid %u)",
                  __FUNCTION__, logging_module_name.AsCString(),
                  process.GetUniqueID());
    return;
  }

  // Time to enqueue the breakpoint so we can wait for logging support to be
  // initialized before we try to tap the libtrace stream.
  AddInitCompletionHook(process);
  if (log)
    log->Printf("StructuredDataDarwinLog::%s post-init hook breakpoint "
                "set for logging module %s (process uid %u)",
                __FUNCTION__, logging_module_name.AsCString(),
                process.GetUniqueID());

  // We need to try the enable here as well, which will succeed in the event
  // that we're attaching to (rather than launching) the process and the
  // process is already past initialization time.  In that case, the completion
  // breakpoint will never get hit and therefore won't start that way.  It
  // doesn't hurt much beyond a bit of bandwidth if we end up doing this twice.
  // It hurts much more if we don't get the logging enabled when the user
  // expects it.
  EnableNow();
}

// -----------------------------------------------------------------------------
// public destructor
// -----------------------------------------------------------------------------

StructuredDataDarwinLog::~StructuredDataDarwinLog() {
  if (m_breakpoint_id != LLDB_INVALID_BREAK_ID) {
    ProcessSP process_sp(GetProcess());
    if (process_sp) {
      process_sp->GetTarget().RemoveBreakpointByID(m_breakpoint_id);
      m_breakpoint_id = LLDB_INVALID_BREAK_ID;
    }
  }
}

#pragma mark -
#pragma mark Private instance methods

// -----------------------------------------------------------------------------
// Private constructors
// -----------------------------------------------------------------------------

StructuredDataDarwinLog::StructuredDataDarwinLog(const ProcessWP &process_wp)
    : StructuredDataPlugin(process_wp), m_recorded_first_timestamp(false),
      m_first_timestamp_seen(0), m_is_enabled(false),
      m_added_breakpoint_mutex(), m_added_breakpoint(),
      m_breakpoint_id(LLDB_INVALID_BREAK_ID) {}

// -----------------------------------------------------------------------------
// Private static methods
// -----------------------------------------------------------------------------

StructuredDataPluginSP
StructuredDataDarwinLog::CreateInstance(Process &process) {
  // Currently only Apple targets support the os_log/os_activity protocol.
  if (process.GetTarget().GetArchitecture().GetTriple().getVendor() ==
      llvm::Triple::VendorType::Apple) {
    auto process_wp = ProcessWP(process.shared_from_this());
    return StructuredDataPluginSP(new StructuredDataDarwinLog(process_wp));
  } else {
    return StructuredDataPluginSP();
  }
}

void StructuredDataDarwinLog::DebuggerInitialize(Debugger &debugger) {
  // Setup parent class first.
  StructuredDataPlugin::InitializeBasePluginForDebugger(debugger);

  // Get parent command.
  auto &interpreter = debugger.GetCommandInterpreter();
  llvm::StringRef parent_command_text = "plugin structured-data";
  auto parent_command =
      interpreter.GetCommandObjectForCommand(parent_command_text);
  if (!parent_command) {
    // Ut oh, parent failed to create parent command.
    // TODO log
    return;
  }

  auto command_name = "darwin-log";
  auto command_sp = CommandObjectSP(new BaseCommand(interpreter));
  bool result = parent_command->LoadSubCommand(command_name, command_sp);
  if (!result) {
    // TODO log it once we setup structured data logging
  }

  if (!PluginManager::GetSettingForPlatformPlugin(
          debugger, StructuredDataDarwinLogProperties::GetSettingName())) {
    const bool is_global_setting = true;
    PluginManager::CreateSettingForStructuredDataPlugin(
        debugger, GetGlobalProperties()->GetValueProperties(),
        ConstString("Properties for the darwin-log"
                    " plug-in."),
        is_global_setting);
  }
}

Status StructuredDataDarwinLog::FilterLaunchInfo(ProcessLaunchInfo &launch_info,
                                                 Target *target) {
  Status error;

  // If we're not debugging this launched process, there's nothing for us to do
  // here.
  if (!launch_info.GetFlags().AnySet(eLaunchFlagDebug))
    return error;

  // Darwin os_log() support automatically adds debug-level and info-level
  // messages when a debugger is attached to a process.  However, with
  // integrated support for debugging built into the command-line LLDB, the
  // user may specifically set to *not* include debug-level and info-level
  // content.  When the user is using the integrated log support, we want to
  // put the kabosh on that automatic adding of info and debug level. This is
  // done by adding an environment variable to the process on launch. (This
  // also means it is not possible to suppress this behavior if attaching to an
  // already-running app).
  // Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_PLATFORM));

  // If the target architecture is not one that supports DarwinLog, we have
  // nothing to do here.
  auto &triple = target ? target->GetArchitecture().GetTriple()
                        : launch_info.GetArchitecture().GetTriple();
  if (triple.getVendor() != llvm::Triple::Apple) {
    return error;
  }

  // If DarwinLog is not enabled (either by explicit user command or via the
  // auto-enable option), then we have nothing to do.
  if (!GetGlobalProperties()->GetEnableOnStartup() &&
      !s_is_explicitly_enabled) {
    // Nothing to do, DarwinLog is not enabled.
    return error;
  }

  // If we don't have parsed configuration info, that implies we have enable-
  // on-startup set up, but we haven't yet attempted to run the enable command.
  if (!target) {
    // We really can't do this without a target.  We need to be able to get to
    // the debugger to get the proper options to do this right.
    // TODO log.
    error.SetErrorString("requires a target to auto-enable DarwinLog.");
    return error;
  }

  DebuggerSP debugger_sp = target->GetDebugger().shared_from_this();
  auto options_sp = GetGlobalEnableOptions(debugger_sp);
  if (!options_sp && debugger_sp) {
    options_sp = ParseAutoEnableOptions(error, *debugger_sp.get());
    if (!options_sp || !error.Success())
      return error;

    // We already parsed the options, save them now so we don't generate them
    // again until the user runs the command manually.
    SetGlobalEnableOptions(debugger_sp, options_sp);
  }

  if (!options_sp->GetEchoToStdErr()) {
    // The user doesn't want to see os_log/NSLog messages echo to stderr. That
    // mechanism is entirely separate from the DarwinLog support. By default we
    // don't want to get it via stderr, because that would be in duplicate of
    // the explicit log support here.

    // Here we need to strip out any OS_ACTIVITY_DT_MODE setting to prevent
    // echoing of os_log()/NSLog() to stderr in the target program.
    launch_info.GetEnvironment().erase("OS_ACTIVITY_DT_MODE");

    // We will also set the env var that tells any downstream launcher from
    // adding OS_ACTIVITY_DT_MODE.
    launch_info.GetEnvironment()["IDE_DISABLED_OS_ACTIVITY_DT_MODE"] = "1";
  }

  // Set the OS_ACTIVITY_MODE env var appropriately to enable/disable debug and
  // info level messages.
  const char *env_var_value;
  if (options_sp->GetIncludeDebugLevel())
    env_var_value = "debug";
  else if (options_sp->GetIncludeInfoLevel())
    env_var_value = "info";
  else
    env_var_value = "default";

  launch_info.GetEnvironment()["OS_ACTIVITY_MODE"] = env_var_value;

  return error;
}

bool StructuredDataDarwinLog::InitCompletionHookCallback(
    void *baton, StoppointCallbackContext *context, lldb::user_id_t break_id,
    lldb::user_id_t break_loc_id) {
  // We hit the init function.  We now want to enqueue our new thread plan,
  // which will in turn enqueue a StepOut thread plan. When the StepOut
  // finishes and control returns to our new thread plan, that is the time when
  // we can execute our logic to enable the logging support.

  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() called", __FUNCTION__);

  // Get the current thread.
  if (!context) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: no context, "
                  "ignoring",
                  __FUNCTION__);
    return false;
  }

  // Get the plugin from the process.
  auto process_sp = context->exe_ctx_ref.GetProcessSP();
  if (!process_sp) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: invalid "
                  "process in context, ignoring",
                  __FUNCTION__);
    return false;
  }
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() call is for process uid %d",
                __FUNCTION__, process_sp->GetUniqueID());

  auto plugin_sp = process_sp->GetStructuredDataPlugin(GetDarwinLogTypeName());
  if (!plugin_sp) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: no plugin for "
                  "feature %s in process uid %u",
                  __FUNCTION__, GetDarwinLogTypeName().AsCString(),
                  process_sp->GetUniqueID());
    return false;
  }

  // Create the callback for when the thread plan completes.
  bool called_enable_method = false;
  const auto process_uid = process_sp->GetUniqueID();

  std::weak_ptr<StructuredDataPlugin> plugin_wp(plugin_sp);
  ThreadPlanCallOnFunctionExit::Callback callback =
      [plugin_wp, &called_enable_method, log, process_uid]() {
        if (log)
          log->Printf("StructuredDataDarwinLog::post-init callback: "
                      "called (process uid %u)",
                      process_uid);

        auto strong_plugin_sp = plugin_wp.lock();
        if (!strong_plugin_sp) {
          if (log)
            log->Printf("StructuredDataDarwinLog::post-init callback: "
                        "plugin no longer exists, ignoring (process "
                        "uid %u)",
                        process_uid);
          return;
        }
        // Make sure we only call it once, just in case the thread plan hits
        // the breakpoint twice.
        if (!called_enable_method) {
          if (log)
            log->Printf("StructuredDataDarwinLog::post-init callback: "
                        "calling EnableNow() (process uid %u)",
                        process_uid);
          static_cast<StructuredDataDarwinLog *>(strong_plugin_sp.get())
              ->EnableNow();
          called_enable_method = true;
        } else {
          // Our breakpoint was hit more than once.  Unexpected but no harm
          // done.  Log it.
          if (log)
            log->Printf("StructuredDataDarwinLog::post-init callback: "
                        "skipping EnableNow(), already called by "
                        "callback [we hit this more than once] "
                        "(process uid %u)",
                        process_uid);
        }
      };

  // Grab the current thread.
  auto thread_sp = context->exe_ctx_ref.GetThreadSP();
  if (!thread_sp) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: failed to "
                  "retrieve the current thread from the execution "
                  "context, nowhere to run the thread plan (process uid "
                  "%u)",
                  __FUNCTION__, process_sp->GetUniqueID());
    return false;
  }

  // Queue the thread plan.
  auto thread_plan_sp = ThreadPlanSP(
      new ThreadPlanCallOnFunctionExit(*thread_sp.get(), callback));
  const bool abort_other_plans = false;
  thread_sp->QueueThreadPlan(thread_plan_sp, abort_other_plans);
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() queuing thread plan on "
                "trace library init method entry (process uid %u)",
                __FUNCTION__, process_sp->GetUniqueID());

  // We return false here to indicate that it isn't a public stop.
  return false;
}

void StructuredDataDarwinLog::AddInitCompletionHook(Process &process) {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() called (process uid %u)",
                __FUNCTION__, process.GetUniqueID());

  // Make sure we haven't already done this.
  {
    std::lock_guard<std::mutex> locker(m_added_breakpoint_mutex);
    if (m_added_breakpoint) {
      if (log)
        log->Printf("StructuredDataDarwinLog::%s() ignoring request, "
                    "breakpoint already set (process uid %u)",
                    __FUNCTION__, process.GetUniqueID());
      return;
    }

    // We're about to do this, don't let anybody else try to do it.
    m_added_breakpoint = true;
  }

  // Set a breakpoint for the process that will kick in when libtrace has
  // finished its initialization.
  Target &target = process.GetTarget();

  // Build up the module list.
  FileSpecList module_spec_list;
  auto module_file_spec =
      FileSpec(GetGlobalProperties()->GetLoggingModuleName());
  module_spec_list.Append(module_file_spec);

  // We aren't specifying a source file set.
  FileSpecList *source_spec_list = nullptr;

  const char *func_name = "_libtrace_init";
  const lldb::addr_t offset = 0;
  const LazyBool skip_prologue = eLazyBoolCalculate;
  // This is an internal breakpoint - the user shouldn't see it.
  const bool internal = true;
  const bool hardware = false;

  auto breakpoint_sp = target.CreateBreakpoint(
      &module_spec_list, source_spec_list, func_name, eFunctionNameTypeFull,
      eLanguageTypeC, offset, skip_prologue, internal, hardware);
  if (!breakpoint_sp) {
    // Huh?  Bail here.
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() failed to set "
                  "breakpoint in module %s, function %s (process uid %u)",
                  __FUNCTION__, GetGlobalProperties()->GetLoggingModuleName(),
                  func_name, process.GetUniqueID());
    return;
  }

  // Set our callback.
  breakpoint_sp->SetCallback(InitCompletionHookCallback, nullptr);
  m_breakpoint_id = breakpoint_sp->GetID();
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() breakpoint set in module %s,"
                "function %s (process uid %u)",
                __FUNCTION__, GetGlobalProperties()->GetLoggingModuleName(),
                func_name, process.GetUniqueID());
}

void StructuredDataDarwinLog::DumpTimestamp(Stream &stream,
                                            uint64_t timestamp) {
  const uint64_t delta_nanos = timestamp - m_first_timestamp_seen;

  const uint64_t hours = delta_nanos / NANOS_PER_HOUR;
  uint64_t nanos_remaining = delta_nanos % NANOS_PER_HOUR;

  const uint64_t minutes = nanos_remaining / NANOS_PER_MINUTE;
  nanos_remaining = nanos_remaining % NANOS_PER_MINUTE;

  const uint64_t seconds = nanos_remaining / NANOS_PER_SECOND;
  nanos_remaining = nanos_remaining % NANOS_PER_SECOND;

  stream.Printf("%02" PRIu64 ":%02" PRIu64 ":%02" PRIu64 ".%09" PRIu64, hours,
                minutes, seconds, nanos_remaining);
}

size_t
StructuredDataDarwinLog::DumpHeader(Stream &output_stream,
                                    const StructuredData::Dictionary &event) {
  StreamString stream;

  ProcessSP process_sp = GetProcess();
  if (!process_sp) {
    // TODO log
    return 0;
  }

  DebuggerSP debugger_sp =
      process_sp->GetTarget().GetDebugger().shared_from_this();
  if (!debugger_sp) {
    // TODO log
    return 0;
  }

  auto options_sp = GetGlobalEnableOptions(debugger_sp);
  if (!options_sp) {
    // TODO log
    return 0;
  }

  // Check if we should even display a header.
  if (!options_sp->GetDisplayAnyHeaderFields())
    return 0;

  stream.PutChar('[');

  int header_count = 0;
  if (options_sp->GetDisplayTimestampRelative()) {
    uint64_t timestamp = 0;
    if (event.GetValueForKeyAsInteger("timestamp", timestamp)) {
      DumpTimestamp(stream, timestamp);
      ++header_count;
    }
  }

  if (options_sp->GetDisplayActivityChain()) {
    llvm::StringRef activity_chain;
    if (event.GetValueForKeyAsString("activity-chain", activity_chain) &&
        !activity_chain.empty()) {
      if (header_count > 0)
        stream.PutChar(',');

      // Display the activity chain, from parent-most to child-most activity,
      // separated by a colon (:).
      stream.PutCString("activity-chain=");
      stream.PutCString(activity_chain);
      ++header_count;
    }
  }

  if (options_sp->GetDisplaySubsystem()) {
    llvm::StringRef subsystem;
    if (event.GetValueForKeyAsString("subsystem", subsystem) &&
        !subsystem.empty()) {
      if (header_count > 0)
        stream.PutChar(',');
      stream.PutCString("subsystem=");
      stream.PutCString(subsystem);
      ++header_count;
    }
  }

  if (options_sp->GetDisplayCategory()) {
    llvm::StringRef category;
    if (event.GetValueForKeyAsString("category", category) &&
        !category.empty()) {
      if (header_count > 0)
        stream.PutChar(',');
      stream.PutCString("category=");
      stream.PutCString(category);
      ++header_count;
    }
  }
  stream.PutCString("] ");

  output_stream.PutCString(stream.GetString());

  return stream.GetSize();
}

size_t StructuredDataDarwinLog::HandleDisplayOfEvent(
    const StructuredData::Dictionary &event, Stream &stream) {
  // Check the type of the event.
  ConstString event_type;
  if (!event.GetValueForKeyAsString("type", event_type)) {
    // Hmm, we expected to get events that describe what they are.  Continue
    // anyway.
    return 0;
  }

  if (event_type != GetLogEventType())
    return 0;

  size_t total_bytes = 0;

  // Grab the message content.
  llvm::StringRef message;
  if (!event.GetValueForKeyAsString("message", message))
    return true;

  // Display the log entry.
  const auto len = message.size();

  total_bytes += DumpHeader(stream, event);

  stream.Write(message.data(), len);
  total_bytes += len;

  // Add an end of line.
  stream.PutChar('\n');
  total_bytes += sizeof(char);

  return total_bytes;
}

void StructuredDataDarwinLog::EnableNow() {
  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() called", __FUNCTION__);

  // Run the enable command.
  auto process_sp = GetProcess();
  if (!process_sp) {
    // Nothing to do.
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: failed to get "
                  "valid process, skipping",
                  __FUNCTION__);
    return;
  }
  if (log)
    log->Printf("StructuredDataDarwinLog::%s() call is for process uid %u",
                __FUNCTION__, process_sp->GetUniqueID());

  // If we have configuration data, we can directly enable it now. Otherwise,
  // we need to run through the command interpreter to parse the auto-run
  // options (which is the only way we get here without having already-parsed
  // configuration data).
  DebuggerSP debugger_sp =
      process_sp->GetTarget().GetDebugger().shared_from_this();
  if (!debugger_sp) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: failed to get "
                  "debugger shared pointer, skipping (process uid %u)",
                  __FUNCTION__, process_sp->GetUniqueID());
    return;
  }

  auto options_sp = GetGlobalEnableOptions(debugger_sp);
  if (!options_sp) {
    // We haven't run the enable command yet.  Just do that now, it'll take
    // care of the rest.
    auto &interpreter = debugger_sp->GetCommandInterpreter();
    const bool success = RunEnableCommand(interpreter);
    if (log) {
      if (success)
        log->Printf("StructuredDataDarwinLog::%s() ran enable command "
                    "successfully for (process uid %u)",
                    __FUNCTION__, process_sp->GetUniqueID());
      else
        log->Printf("StructuredDataDarwinLog::%s() error: running "
                    "enable command failed (process uid %u)",
                    __FUNCTION__, process_sp->GetUniqueID());
    }
    // Report failures to the debugger error stream.
    auto error_stream_sp = debugger_sp->GetAsyncErrorStream();
    if (error_stream_sp) {
      error_stream_sp->Printf("failed to configure DarwinLog "
                              "support\n");
      error_stream_sp->Flush();
    }
    return;
  }

  // We've previously been enabled. We will re-enable now with the previously
  // specified options.
  auto config_sp = options_sp->BuildConfigurationData(true);
  if (!config_sp) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() warning: failed to "
                  "build configuration data for enable options, skipping "
                  "(process uid %u)",
                  __FUNCTION__, process_sp->GetUniqueID());
    return;
  }

  // We can run it directly.
  // Send configuration to the feature by way of the process.
  const Status error =
      process_sp->ConfigureStructuredData(GetDarwinLogTypeName(), config_sp);

  // Report results.
  if (!error.Success()) {
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() "
                  "ConfigureStructuredData() call failed "
                  "(process uid %u): %s",
                  __FUNCTION__, process_sp->GetUniqueID(), error.AsCString());
    auto error_stream_sp = debugger_sp->GetAsyncErrorStream();
    if (error_stream_sp) {
      error_stream_sp->Printf("failed to configure DarwinLog "
                              "support: %s\n",
                              error.AsCString());
      error_stream_sp->Flush();
    }
    m_is_enabled = false;
  } else {
    m_is_enabled = true;
    if (log)
      log->Printf("StructuredDataDarwinLog::%s() success via direct "
                  "configuration (process uid %u)",
                  __FUNCTION__, process_sp->GetUniqueID());
  }
}