summaryrefslogtreecommitdiff
path: root/scripts/lib/kdoc/kdoc_parser.py
blob: 4f036c720b360af9c753b76c879d72da24dc5c93 (plain) (blame)
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
#!/usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0
# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
#
# pylint: disable=C0301,C0302,R0904,R0912,R0913,R0914,R0915,R0917,R1702

"""
kdoc_parser
===========

Read a C language source or header FILE and extract embedded
documentation comments
"""

import argparse
import re
from pprint import pformat

from kdoc_re import NestedMatch, KernRe


#
# Regular expressions used to parse kernel-doc markups at KernelDoc class.
#
# Let's declare them in lowercase outside any class to make easier to
# convert from the python script.
#
# As those are evaluated at the beginning, no need to cache them
#

# Allow whitespace at end of comment start.
doc_start = KernRe(r'^/\*\*\s*$', cache=False)

doc_end = KernRe(r'\*/', cache=False)
doc_com = KernRe(r'\s*\*\s*', cache=False)
doc_com_body = KernRe(r'\s*\* ?', cache=False)
doc_decl = doc_com + KernRe(r'(\w+)', cache=False)

# @params and a strictly limited set of supported section names
# Specifically:
#   Match @word:
#         @...:
#         @{section-name}:
# while trying to not match literal block starts like "example::"
#
doc_sect = doc_com + \
            KernRe(r'\s*(\@[.\w]+|\@\.\.\.|description|context|returns?|notes?|examples?)\s*:([^:].*)?$',
                flags=re.I, cache=False)

doc_content = doc_com_body + KernRe(r'(.*)', cache=False)
doc_block = doc_com + KernRe(r'DOC:\s*(.*)?', cache=False)
doc_inline_start = KernRe(r'^\s*/\*\*\s*$', cache=False)
doc_inline_sect = KernRe(r'\s*\*\s*(@\s*[\w][\w\.]*\s*):(.*)', cache=False)
doc_inline_end = KernRe(r'^\s*\*/\s*$', cache=False)
doc_inline_oneline = KernRe(r'^\s*/\*\*\s*(@[\w\s]+):\s*(.*)\s*\*/\s*$', cache=False)
attribute = KernRe(r"__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)",
               flags=re.I | re.S, cache=False)

export_symbol = KernRe(r'^\s*EXPORT_SYMBOL(_GPL)?\s*\(\s*(\w+)\s*\)\s*', cache=False)
export_symbol_ns = KernRe(r'^\s*EXPORT_SYMBOL_NS(_GPL)?\s*\(\s*(\w+)\s*,\s*"\S+"\)\s*', cache=False)

type_param = KernRe(r"\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)", cache=False)


class KernelDoc:
    """
    Read a C language source or header FILE and extract embedded
    documentation comments.
    """

    # Parser states
    STATE_NORMAL        = 0        # normal code
    STATE_NAME          = 1        # looking for function name
    STATE_BODY_MAYBE    = 2        # body - or maybe more description
    STATE_BODY          = 3        # the body of the comment
    STATE_BODY_WITH_BLANK_LINE = 4 # the body which has a blank line
    STATE_PROTO         = 5        # scanning prototype
    STATE_DOCBLOCK      = 6        # documentation block
    STATE_INLINE        = 7        # gathering doc outside main block

    st_name = [
        "NORMAL",
        "NAME",
        "BODY_MAYBE",
        "BODY",
        "BODY_WITH_BLANK_LINE",
        "PROTO",
        "DOCBLOCK",
        "INLINE",
    ]

    # Inline documentation state
    STATE_INLINE_NA     = 0 # not applicable ($state != STATE_INLINE)
    STATE_INLINE_NAME   = 1 # looking for member name (@foo:)
    STATE_INLINE_TEXT   = 2 # looking for member documentation
    STATE_INLINE_END    = 3 # done
    STATE_INLINE_ERROR  = 4 # error - Comment without header was found.
                            # Spit a warning as it's not
                            # proper kernel-doc and ignore the rest.

    st_inline_name = [
        "",
        "_NAME",
        "_TEXT",
        "_END",
        "_ERROR",
    ]

    # Section names

    section_default = "Description"  # default section
    section_intro = "Introduction"
    section_context = "Context"
    section_return = "Return"

    undescribed = "-- undescribed --"

    def __init__(self, config, fname):
        """Initialize internal variables"""

        self.fname = fname
        self.config = config

        # Initial state for the state machines
        self.state = self.STATE_NORMAL
        self.inline_doc_state = self.STATE_INLINE_NA

        # Store entry currently being processed
        self.entry = None

        # Place all potential outputs into an array
        self.entries = []

    # TODO: rename to emit_message after removal of kernel-doc.pl
    def emit_warning(self, ln, msg, warning=True):
        """Emit a message"""

        log_msg = f"{self.fname}:{ln} {msg}"

        if not warning:
            self.config.log.info(log_msg)
            return

        if self.entry:
            # Delegate warning output to output logic, as this way it
            # will report warnings/info only for symbols that are output

            self.entry.warnings.append(log_msg)
            return

        self.config.log.warning(log_msg)

    def dump_section(self, start_new=True):
        """
        Dumps section contents to arrays/hashes intended for that purpose.
        """

        name = self.entry.section
        contents = self.entry.contents

        if type_param.match(name):
            name = type_param.group(1)

            self.entry.parameterdescs[name] = contents
            self.entry.parameterdesc_start_lines[name] = self.entry.new_start_line

            self.entry.sectcheck += name + " "
            self.entry.new_start_line = 0

        elif name == "@...":
            name = "..."
            self.entry.parameterdescs[name] = contents
            self.entry.sectcheck += name + " "
            self.entry.parameterdesc_start_lines[name] = self.entry.new_start_line
            self.entry.new_start_line = 0

        else:
            if name in self.entry.sections and self.entry.sections[name] != "":
                # Only warn on user-specified duplicate section names
                if name != self.section_default:
                    self.emit_warning(self.entry.new_start_line,
                                      f"duplicate section name '{name}'\n")
                self.entry.sections[name] += contents
            else:
                self.entry.sections[name] = contents
                self.entry.sectionlist.append(name)
                self.entry.section_start_lines[name] = self.entry.new_start_line
                self.entry.new_start_line = 0

#        self.config.log.debug("Section: %s : %s", name, pformat(vars(self.entry)))

        if start_new:
            self.entry.section = self.section_default
            self.entry.contents = ""

    # TODO: rename it to store_declaration after removal of kernel-doc.pl
    def output_declaration(self, dtype, name, **args):
        """
        Stores the entry into an entry array.

        The actual output and output filters will be handled elsewhere
        """

        # The implementation here is different than the original kernel-doc:
        # instead of checking for output filters or actually output anything,
        # it just stores the declaration content at self.entries, as the
        # output will happen on a separate class.
        #
        # For now, we're keeping the same name of the function just to make
        # easier to compare the source code of both scripts

        args["declaration_start_line"] = self.entry.declaration_start_line
        args["type"] = dtype
        args["warnings"] = self.entry.warnings

        # TODO: use colletions.OrderedDict to remove sectionlist

        sections = args.get('sections', {})
        sectionlist = args.get('sectionlist', [])

        # Drop empty sections
        # TODO: improve empty sections logic to emit warnings
        for section in ["Description", "Return"]:
            if section in sectionlist:
                if not sections[section].rstrip():
                    del sections[section]
                    sectionlist.remove(section)

        self.entries.append((name, args))

        self.config.log.debug("Output: %s:%s = %s", dtype, name, pformat(args))

    def reset_state(self, ln):
        """
        Ancillary routine to create a new entry. It initializes all
        variables used by the state machine.
        """

        self.entry = argparse.Namespace

        self.entry.contents = ""
        self.entry.function = ""
        self.entry.sectcheck = ""
        self.entry.struct_actual = ""
        self.entry.prototype = ""

        self.entry.warnings = []

        self.entry.parameterlist = []
        self.entry.parameterdescs = {}
        self.entry.parametertypes = {}
        self.entry.parameterdesc_start_lines = {}

        self.entry.section_start_lines = {}
        self.entry.sectionlist = []
        self.entry.sections = {}

        self.entry.anon_struct_union = False

        self.entry.leading_space = None

        # State flags
        self.state = self.STATE_NORMAL
        self.inline_doc_state = self.STATE_INLINE_NA
        self.entry.brcount = 0

        self.entry.in_doc_sect = False
        self.entry.declaration_start_line = ln + 1

    def push_parameter(self, ln, decl_type, param, dtype,
                       org_arg, declaration_name):
        """
        Store parameters and their descriptions at self.entry.
        """

        if self.entry.anon_struct_union and dtype == "" and param == "}":
            return  # Ignore the ending }; from anonymous struct/union

        self.entry.anon_struct_union = False

        param = KernRe(r'[\[\)].*').sub('', param, count=1)

        if dtype == "" and param.endswith("..."):
            if KernRe(r'\w\.\.\.$').search(param):
                # For named variable parameters of the form `x...`,
                # remove the dots
                param = param[:-3]
            else:
                # Handles unnamed variable parameters
                param = "..."

            if param not in self.entry.parameterdescs or \
                not self.entry.parameterdescs[param]:

                self.entry.parameterdescs[param] = "variable arguments"

        elif dtype == "" and (not param or param == "void"):
            param = "void"
            self.entry.parameterdescs[param] = "no arguments"

        elif dtype == "" and param in ["struct", "union"]:
            # Handle unnamed (anonymous) union or struct
            dtype = param
            param = "{unnamed_" + param + "}"
            self.entry.parameterdescs[param] = "anonymous\n"
            self.entry.anon_struct_union = True

        # Handle cache group enforcing variables: they do not need
        # to be described in header files
        elif "__cacheline_group" in param:
            # Ignore __cacheline_group_begin and __cacheline_group_end
            return

        # Warn if parameter has no description
        # (but ignore ones starting with # as these are not parameters
        # but inline preprocessor statements)
        if param not in self.entry.parameterdescs and not param.startswith("#"):
            self.entry.parameterdescs[param] = self.undescribed

            if "." not in param:
                if decl_type == 'function':
                    dname = f"{decl_type} parameter"
                else:
                    dname = f"{decl_type} member"

                self.emit_warning(ln,
                                  f"{dname} '{param}' not described in '{declaration_name}'")

        # Strip spaces from param so that it is one continuous string on
        # parameterlist. This fixes a problem where check_sections()
        # cannot find a parameter like "addr[6 + 2]" because it actually
        # appears as "addr[6", "+", "2]" on the parameter list.
        # However, it's better to maintain the param string unchanged for
        # output, so just weaken the string compare in check_sections()
        # to ignore "[blah" in a parameter string.

        self.entry.parameterlist.append(param)
        org_arg = KernRe(r'\s\s+').sub(' ', org_arg)
        self.entry.parametertypes[param] = org_arg

    def save_struct_actual(self, actual):
        """
        Strip all spaces from the actual param so that it looks like
        one string item.
        """

        actual = KernRe(r'\s*').sub("", actual, count=1)

        self.entry.struct_actual += actual + " "

    def create_parameter_list(self, ln, decl_type, args,
                              splitter, declaration_name):
        """
        Creates a list of parameters, storing them at self.entry.
        """

        # temporarily replace all commas inside function pointer definition
        arg_expr = KernRe(r'(\([^\),]+),')
        while arg_expr.search(args):
            args = arg_expr.sub(r"\1#", args)

        for arg in args.split(splitter):
            # Strip comments
            arg = KernRe(r'\/\*.*\*\/').sub('', arg)

            # Ignore argument attributes
            arg = KernRe(r'\sPOS0?\s').sub(' ', arg)

            # Strip leading/trailing spaces
            arg = arg.strip()
            arg = KernRe(r'\s+').sub(' ', arg, count=1)

            if arg.startswith('#'):
                # Treat preprocessor directive as a typeless variable just to fill
                # corresponding data structures "correctly". Catch it later in
                # output_* subs.

                # Treat preprocessor directive as a typeless variable
                self.push_parameter(ln, decl_type, arg, "",
                                    "", declaration_name)

            elif KernRe(r'\(.+\)\s*\(').search(arg):
                # Pointer-to-function

                arg = arg.replace('#', ',')

                r = KernRe(r'[^\(]+\(\*?\s*([\w\[\]\.]*)\s*\)')
                if r.match(arg):
                    param = r.group(1)
                else:
                    self.emit_warning(ln, f"Invalid param: {arg}")
                    param = arg

                dtype = KernRe(r'([^\(]+\(\*?)\s*' + re.escape(param)).sub(r'\1', arg)
                self.save_struct_actual(param)
                self.push_parameter(ln, decl_type, param, dtype,
                                    arg, declaration_name)

            elif KernRe(r'\(.+\)\s*\[').search(arg):
                # Array-of-pointers

                arg = arg.replace('#', ',')
                r = KernRe(r'[^\(]+\(\s*\*\s*([\w\[\]\.]*?)\s*(\s*\[\s*[\w]+\s*\]\s*)*\)')
                if r.match(arg):
                    param = r.group(1)
                else:
                    self.emit_warning(ln, f"Invalid param: {arg}")
                    param = arg

                dtype = KernRe(r'([^\(]+\(\*?)\s*' + re.escape(param)).sub(r'\1', arg)

                self.save_struct_actual(param)
                self.push_parameter(ln, decl_type, param, dtype,
                                    arg, declaration_name)

            elif arg:
                arg = KernRe(r'\s*:\s*').sub(":", arg)
                arg = KernRe(r'\s*\[').sub('[', arg)

                args = KernRe(r'\s*,\s*').split(arg)
                if args[0] and '*' in args[0]:
                    args[0] = re.sub(r'(\*+)\s*', r' \1', args[0])

                first_arg = []
                r = KernRe(r'^(.*\s+)(.*?\[.*\].*)$')
                if args[0] and r.match(args[0]):
                    args.pop(0)
                    first_arg.extend(r.group(1))
                    first_arg.append(r.group(2))
                else:
                    first_arg = KernRe(r'\s+').split(args.pop(0))

                args.insert(0, first_arg.pop())
                dtype = ' '.join(first_arg)

                for param in args:
                    if KernRe(r'^(\*+)\s*(.*)').match(param):
                        r = KernRe(r'^(\*+)\s*(.*)')
                        if not r.match(param):
                            self.emit_warning(ln, f"Invalid param: {param}")
                            continue

                        param = r.group(1)

                        self.save_struct_actual(r.group(2))
                        self.push_parameter(ln, decl_type, r.group(2),
                                            f"{dtype} {r.group(1)}",
                                            arg, declaration_name)

                    elif KernRe(r'(.*?):(\w+)').search(param):
                        r = KernRe(r'(.*?):(\w+)')
                        if not r.match(param):
                            self.emit_warning(ln, f"Invalid param: {param}")
                            continue

                        if dtype != "":  # Skip unnamed bit-fields
                            self.save_struct_actual(r.group(1))
                            self.push_parameter(ln, decl_type, r.group(1),
                                                f"{dtype}:{r.group(2)}",
                                                arg, declaration_name)
                    else:
                        self.save_struct_actual(param)
                        self.push_parameter(ln, decl_type, param, dtype,
                                            arg, declaration_name)

    def check_sections(self, ln, decl_name, decl_type, sectcheck, prmscheck):
        """
        Check for errors inside sections, emitting warnings if not found
        parameters are described.
        """

        sects = sectcheck.split()
        prms = prmscheck.split()
        err = False

        for sx in range(len(sects)):                  # pylint: disable=C0200
            err = True
            for px in range(len(prms)):               # pylint: disable=C0200
                prm_clean = prms[px]
                prm_clean = KernRe(r'\[.*\]').sub('', prm_clean)
                prm_clean = attribute.sub('', prm_clean)

                # ignore array size in a parameter string;
                # however, the original param string may contain
                # spaces, e.g.:  addr[6 + 2]
                # and this appears in @prms as "addr[6" since the
                # parameter list is split at spaces;
                # hence just ignore "[..." for the sections check;
                prm_clean = KernRe(r'\[.*').sub('', prm_clean)

                if prm_clean == sects[sx]:
                    err = False
                    break

            if err:
                if decl_type == 'function':
                    dname = f"{decl_type} parameter"
                else:
                    dname = f"{decl_type} member"

                self.emit_warning(ln,
                                  f"Excess {dname} '{sects[sx]}' description in '{decl_name}'")

    def check_return_section(self, ln, declaration_name, return_type):
        """
        If the function doesn't return void, warns about the lack of a
        return description.
        """

        if not self.config.wreturn:
            return

        # Ignore an empty return type (It's a macro)
        # Ignore functions with a "void" return type (but not "void *")
        if not return_type or KernRe(r'void\s*\w*\s*$').search(return_type):
            return

        if not self.entry.sections.get("Return", None):
            self.emit_warning(ln,
                              f"No description found for return value of '{declaration_name}'")

    def dump_struct(self, ln, proto):
        """
        Store an entry for an struct or union
        """

        type_pattern = r'(struct|union)'

        qualifiers = [
            "__attribute__",
            "__packed",
            "__aligned",
            "____cacheline_aligned_in_smp",
            "____cacheline_aligned",
        ]

        definition_body = r'\{(.*)\}\s*' + "(?:" + '|'.join(qualifiers) + ")?"
        struct_members = KernRe(type_pattern + r'([^\{\};]+)(\{)([^\{\}]*)(\})([^\{\}\;]*)(\;)')

        # Extract struct/union definition
        members = None
        declaration_name = None
        decl_type = None

        r = KernRe(type_pattern + r'\s+(\w+)\s*' + definition_body)
        if r.search(proto):
            decl_type = r.group(1)
            declaration_name = r.group(2)
            members = r.group(3)
        else:
            r = KernRe(r'typedef\s+' + type_pattern + r'\s*' + definition_body + r'\s*(\w+)\s*;')

            if r.search(proto):
                decl_type = r.group(1)
                declaration_name = r.group(3)
                members = r.group(2)

        if not members:
            self.emit_warning(ln, f"{proto} error: Cannot parse struct or union!")
            return

        if self.entry.identifier != declaration_name:
            self.emit_warning(ln,
                              f"expecting prototype for {decl_type} {self.entry.identifier}. Prototype was for {decl_type} {declaration_name} instead\n")
            return

        args_pattern = r'([^,)]+)'

        sub_prefixes = [
            (KernRe(r'\/\*\s*private:.*?\/\*\s*public:.*?\*\/', re.S | re.I), ''),
            (KernRe(r'\/\*\s*private:.*', re.S | re.I), ''),

            # Strip comments
            (KernRe(r'\/\*.*?\*\/', re.S), ''),

            # Strip attributes
            (attribute, ' '),
            (KernRe(r'\s*__aligned\s*\([^;]*\)', re.S), ' '),
            (KernRe(r'\s*__counted_by\s*\([^;]*\)', re.S), ' '),
            (KernRe(r'\s*__counted_by_(le|be)\s*\([^;]*\)', re.S), ' '),
            (KernRe(r'\s*__packed\s*', re.S), ' '),
            (KernRe(r'\s*CRYPTO_MINALIGN_ATTR', re.S), ' '),
            (KernRe(r'\s*____cacheline_aligned_in_smp', re.S), ' '),
            (KernRe(r'\s*____cacheline_aligned', re.S), ' '),

            # Unwrap struct_group macros based on this definition:
            # __struct_group(TAG, NAME, ATTRS, MEMBERS...)
            # which has variants like: struct_group(NAME, MEMBERS...)
            # Only MEMBERS arguments require documentation.
            #
            # Parsing them happens on two steps:
            #
            # 1. drop struct group arguments that aren't at MEMBERS,
            #    storing them as STRUCT_GROUP(MEMBERS)
            #
            # 2. remove STRUCT_GROUP() ancillary macro.
            #
            # The original logic used to remove STRUCT_GROUP() using an
            # advanced regex:
            #
            #   \bSTRUCT_GROUP(\(((?:(?>[^)(]+)|(?1))*)\))[^;]*;
            #
            # with two patterns that are incompatible with
            # Python re module, as it has:
            #
            #   - a recursive pattern: (?1)
            #   - an atomic grouping: (?>...)
            #
            # I tried a simpler version: but it didn't work either:
            #   \bSTRUCT_GROUP\(([^\)]+)\)[^;]*;
            #
            # As it doesn't properly match the end parenthesis on some cases.
            #
            # So, a better solution was crafted: there's now a NestedMatch
            # class that ensures that delimiters after a search are properly
            # matched. So, the implementation to drop STRUCT_GROUP() will be
            # handled in separate.

            (KernRe(r'\bstruct_group\s*\(([^,]*,)', re.S), r'STRUCT_GROUP('),
            (KernRe(r'\bstruct_group_attr\s*\(([^,]*,){2}', re.S), r'STRUCT_GROUP('),
            (KernRe(r'\bstruct_group_tagged\s*\(([^,]*),([^,]*),', re.S), r'struct \1 \2; STRUCT_GROUP('),
            (KernRe(r'\b__struct_group\s*\(([^,]*,){3}', re.S), r'STRUCT_GROUP('),

            # Replace macros
            #
            # TODO: use NestedMatch for FOO($1, $2, ...) matches
            #
            # it is better to also move those to the NestedMatch logic,
            # to ensure that parenthesis will be properly matched.

            (KernRe(r'__ETHTOOL_DECLARE_LINK_MODE_MASK\s*\(([^\)]+)\)', re.S), r'DECLARE_BITMAP(\1, __ETHTOOL_LINK_MODE_MASK_NBITS)'),
            (KernRe(r'DECLARE_PHY_INTERFACE_MASK\s*\(([^\)]+)\)', re.S), r'DECLARE_BITMAP(\1, PHY_INTERFACE_MODE_MAX)'),
            (KernRe(r'DECLARE_BITMAP\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'unsigned long \1[BITS_TO_LONGS(\2)]'),
            (KernRe(r'DECLARE_HASHTABLE\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'unsigned long \1[1 << ((\2) - 1)]'),
            (KernRe(r'DECLARE_KFIFO\s*\(' + args_pattern + r',\s*' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\2 *\1'),
            (KernRe(r'DECLARE_KFIFO_PTR\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\2 *\1'),
            (KernRe(r'(?:__)?DECLARE_FLEX_ARRAY\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\1 \2[]'),
            (KernRe(r'DEFINE_DMA_UNMAP_ADDR\s*\(' + args_pattern + r'\)', re.S), r'dma_addr_t \1'),
            (KernRe(r'DEFINE_DMA_UNMAP_LEN\s*\(' + args_pattern + r'\)', re.S), r'__u32 \1'),
        ]

        # Regexes here are guaranteed to have the end limiter matching
        # the start delimiter. Yet, right now, only one replace group
        # is allowed.

        sub_nested_prefixes = [
            (re.compile(r'\bSTRUCT_GROUP\('), r'\1'),
        ]

        for search, sub in sub_prefixes:
            members = search.sub(sub, members)

        nested = NestedMatch()

        for search, sub in sub_nested_prefixes:
            members = nested.sub(search, sub, members)

        # Keeps the original declaration as-is
        declaration = members

        # Split nested struct/union elements
        #
        # This loop was simpler at the original kernel-doc perl version, as
        #   while ($members =~ m/$struct_members/) { ... }
        # reads 'members' string on each interaction.
        #
        # Python behavior is different: it parses 'members' only once,
        # creating a list of tuples from the first interaction.
        #
        # On other words, this won't get nested structs.
        #
        # So, we need to have an extra loop on Python to override such
        # re limitation.

        while True:
            tuples = struct_members.findall(members)
            if not tuples:
                break

            for t in tuples:
                newmember = ""
                maintype = t[0]
                s_ids = t[5]
                content = t[3]

                oldmember = "".join(t)

                for s_id in s_ids.split(','):
                    s_id = s_id.strip()

                    newmember += f"{maintype} {s_id}; "
                    s_id = KernRe(r'[:\[].*').sub('', s_id)
                    s_id = KernRe(r'^\s*\**(\S+)\s*').sub(r'\1', s_id)

                    for arg in content.split(';'):
                        arg = arg.strip()

                        if not arg:
                            continue

                        r = KernRe(r'^([^\(]+\(\*?\s*)([\w\.]*)(\s*\).*)')
                        if r.match(arg):
                            # Pointer-to-function
                            dtype = r.group(1)
                            name = r.group(2)
                            extra = r.group(3)

                            if not name:
                                continue

                            if not s_id:
                                # Anonymous struct/union
                                newmember += f"{dtype}{name}{extra}; "
                            else:
                                newmember += f"{dtype}{s_id}.{name}{extra}; "

                        else:
                            arg = arg.strip()
                            # Handle bitmaps
                            arg = KernRe(r':\s*\d+\s*').sub('', arg)

                            # Handle arrays
                            arg = KernRe(r'\[.*\]').sub('', arg)

                            # Handle multiple IDs
                            arg = KernRe(r'\s*,\s*').sub(',', arg)

                            r = KernRe(r'(.*)\s+([\S+,]+)')

                            if r.search(arg):
                                dtype = r.group(1)
                                names = r.group(2)
                            else:
                                newmember += f"{arg}; "
                                continue

                            for name in names.split(','):
                                name = KernRe(r'^\s*\**(\S+)\s*').sub(r'\1', name).strip()

                                if not name:
                                    continue

                                if not s_id:
                                    # Anonymous struct/union
                                    newmember += f"{dtype} {name}; "
                                else:
                                    newmember += f"{dtype} {s_id}.{name}; "

                members = members.replace(oldmember, newmember)

        # Ignore other nested elements, like enums
        members = re.sub(r'(\{[^\{\}]*\})', '', members)

        self.create_parameter_list(ln, decl_type, members, ';',
                                   declaration_name)
        self.check_sections(ln, declaration_name, decl_type,
                            self.entry.sectcheck, self.entry.struct_actual)

        # Adjust declaration for better display
        declaration = KernRe(r'([\{;])').sub(r'\1\n', declaration)
        declaration = KernRe(r'\}\s+;').sub('};', declaration)

        # Better handle inlined enums
        while True:
            r = KernRe(r'(enum\s+\{[^\}]+),([^\n])')
            if not r.search(declaration):
                break

            declaration = r.sub(r'\1,\n\2', declaration)

        def_args = declaration.split('\n')
        level = 1
        declaration = ""
        for clause in def_args:

            clause = clause.strip()
            clause = KernRe(r'\s+').sub(' ', clause, count=1)

            if not clause:
                continue

            if '}' in clause and level > 1:
                level -= 1

            if not KernRe(r'^\s*#').match(clause):
                declaration += "\t" * level

            declaration += "\t" + clause + "\n"
            if "{" in clause and "}" not in clause:
                level += 1

        self.output_declaration(decl_type, declaration_name,
                                struct=declaration_name,
                                definition=declaration,
                                parameterlist=self.entry.parameterlist,
                                parameterdescs=self.entry.parameterdescs,
                                parametertypes=self.entry.parametertypes,
                                parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
                                sectionlist=self.entry.sectionlist,
                                sections=self.entry.sections,
                                section_start_lines=self.entry.section_start_lines,
                                purpose=self.entry.declaration_purpose)

    def dump_enum(self, ln, proto):
        """
        Stores an enum inside self.entries array.
        """

        # Ignore members marked private
        proto = KernRe(r'\/\*\s*private:.*?\/\*\s*public:.*?\*\/', flags=re.S).sub('', proto)
        proto = KernRe(r'\/\*\s*private:.*}', flags=re.S).sub('}', proto)

        # Strip comments
        proto = KernRe(r'\/\*.*?\*\/', flags=re.S).sub('', proto)

        # Strip #define macros inside enums
        proto = KernRe(r'#\s*((define|ifdef|if)\s+|endif)[^;]*;', flags=re.S).sub('', proto)

        members = None
        declaration_name = None

        r = KernRe(r'typedef\s+enum\s*\{(.*)\}\s*(\w*)\s*;')
        if r.search(proto):
            declaration_name = r.group(2)
            members = r.group(1).rstrip()
        else:
            r = KernRe(r'enum\s+(\w*)\s*\{(.*)\}')
            if r.match(proto):
                declaration_name = r.group(1)
                members = r.group(2).rstrip()

        if not members:
            self.emit_warning(ln, f"{proto}: error: Cannot parse enum!")
            return

        if self.entry.identifier != declaration_name:
            if self.entry.identifier == "":
                self.emit_warning(ln,
                                  f"{proto}: wrong kernel-doc identifier on prototype")
            else:
                self.emit_warning(ln,
                                  f"expecting prototype for enum {self.entry.identifier}. Prototype was for enum {declaration_name} instead")
            return

        if not declaration_name:
            declaration_name = "(anonymous)"

        member_set = set()

        members = KernRe(r'\([^;]*?[\)]').sub('', members)

        for arg in members.split(','):
            if not arg:
                continue
            arg = KernRe(r'^\s*(\w+).*').sub(r'\1', arg)
            self.entry.parameterlist.append(arg)
            if arg not in self.entry.parameterdescs:
                self.entry.parameterdescs[arg] = self.undescribed
                self.emit_warning(ln,
                                  f"Enum value '{arg}' not described in enum '{declaration_name}'")
            member_set.add(arg)

        for k in self.entry.parameterdescs:
            if k not in member_set:
                self.emit_warning(ln,
                                  f"Excess enum value '%{k}' description in '{declaration_name}'")

        self.output_declaration('enum', declaration_name,
                                enum=declaration_name,
                                parameterlist=self.entry.parameterlist,
                                parameterdescs=self.entry.parameterdescs,
                                parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
                                sectionlist=self.entry.sectionlist,
                                sections=self.entry.sections,
                                section_start_lines=self.entry.section_start_lines,
                                purpose=self.entry.declaration_purpose)

    def dump_declaration(self, ln, prototype):
        """
        Stores a data declaration inside self.entries array.
        """

        if self.entry.decl_type == "enum":
            self.dump_enum(ln, prototype)
            return

        if self.entry.decl_type == "typedef":
            self.dump_typedef(ln, prototype)
            return

        if self.entry.decl_type in ["union", "struct"]:
            self.dump_struct(ln, prototype)
            return

        self.output_declaration(self.entry.decl_type, prototype,
                                entry=self.entry)

    def dump_function(self, ln, prototype):
        """
        Stores a function of function macro inside self.entries array.
        """

        func_macro = False
        return_type = ''
        decl_type = 'function'

        # Prefixes that would be removed
        sub_prefixes = [
            (r"^static +", "", 0),
            (r"^extern +", "", 0),
            (r"^asmlinkage +", "", 0),
            (r"^inline +", "", 0),
            (r"^__inline__ +", "", 0),
            (r"^__inline +", "", 0),
            (r"^__always_inline +", "", 0),
            (r"^noinline +", "", 0),
            (r"^__FORTIFY_INLINE +", "", 0),
            (r"__init +", "", 0),
            (r"__init_or_module +", "", 0),
            (r"__deprecated +", "", 0),
            (r"__flatten +", "", 0),
            (r"__meminit +", "", 0),
            (r"__must_check +", "", 0),
            (r"__weak +", "", 0),
            (r"__sched +", "", 0),
            (r"_noprof", "", 0),
            (r"__printf\s*\(\s*\d*\s*,\s*\d*\s*\) +", "", 0),
            (r"__(?:re)?alloc_size\s*\(\s*\d+\s*(?:,\s*\d+\s*)?\) +", "", 0),
            (r"__diagnose_as\s*\(\s*\S+\s*(?:,\s*\d+\s*)*\) +", "", 0),
            (r"DECL_BUCKET_PARAMS\s*\(\s*(\S+)\s*,\s*(\S+)\s*\)", r"\1, \2", 0),
            (r"__attribute_const__ +", "", 0),

            # It seems that Python support for re.X is broken:
            # At least for me (Python 3.13), this didn't work
#            (r"""
#              __attribute__\s*\(\(
#                (?:
#                    [\w\s]+          # attribute name
#                    (?:\([^)]*\))?   # attribute arguments
#                    \s*,?            # optional comma at the end
#                )+
#              \)\)\s+
#             """, "", re.X),

            # So, remove whitespaces and comments from it
            (r"__attribute__\s*\(\((?:[\w\s]+(?:\([^)]*\))?\s*,?)+\)\)\s+", "", 0),
        ]

        for search, sub, flags in sub_prefixes:
            prototype = KernRe(search, flags).sub(sub, prototype)

        # Macros are a special case, as they change the prototype format
        new_proto = KernRe(r"^#\s*define\s+").sub("", prototype)
        if new_proto != prototype:
            is_define_proto = True
            prototype = new_proto
        else:
            is_define_proto = False

        # Yes, this truly is vile.  We are looking for:
        # 1. Return type (may be nothing if we're looking at a macro)
        # 2. Function name
        # 3. Function parameters.
        #
        # All the while we have to watch out for function pointer parameters
        # (which IIRC is what the two sections are for), C types (these
        # regexps don't even start to express all the possibilities), and
        # so on.
        #
        # If you mess with these regexps, it's a good idea to check that
        # the following functions' documentation still comes out right:
        # - parport_register_device (function pointer parameters)
        # - atomic_set (macro)
        # - pci_match_device, __copy_to_user (long return type)

        name = r'[a-zA-Z0-9_~:]+'
        prototype_end1 = r'[^\(]*'
        prototype_end2 = r'[^\{]*'
        prototype_end = fr'\(({prototype_end1}|{prototype_end2})\)'

        # Besides compiling, Perl qr{[\w\s]+} works as a non-capturing group.
        # So, this needs to be mapped in Python with (?:...)? or (?:...)+

        type1 = r'(?:[\w\s]+)?'
        type2 = r'(?:[\w\s]+\*+)+'

        found = False

        if is_define_proto:
            r = KernRe(r'^()(' + name + r')\s+')

            if r.search(prototype):
                return_type = ''
                declaration_name = r.group(2)
                func_macro = True

                found = True

        if not found:
            patterns = [
                rf'^()({name})\s*{prototype_end}',
                rf'^({type1})\s+({name})\s*{prototype_end}',
                rf'^({type2})\s*({name})\s*{prototype_end}',
            ]

            for p in patterns:
                r = KernRe(p)

                if r.match(prototype):

                    return_type = r.group(1)
                    declaration_name = r.group(2)
                    args = r.group(3)

                    self.create_parameter_list(ln, decl_type, args, ',',
                                               declaration_name)

                    found = True
                    break
        if not found:
            self.emit_warning(ln,
                              f"cannot understand function prototype: '{prototype}'")
            return

        if self.entry.identifier != declaration_name:
            self.emit_warning(ln,
                              f"expecting prototype for {self.entry.identifier}(). Prototype was for {declaration_name}() instead")
            return

        prms = " ".join(self.entry.parameterlist)
        self.check_sections(ln, declaration_name, "function",
                            self.entry.sectcheck, prms)

        self.check_return_section(ln, declaration_name, return_type)

        if 'typedef' in return_type:
            self.output_declaration(decl_type, declaration_name,
                                    function=declaration_name,
                                    typedef=True,
                                    functiontype=return_type,
                                    parameterlist=self.entry.parameterlist,
                                    parameterdescs=self.entry.parameterdescs,
                                    parametertypes=self.entry.parametertypes,
                                    parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
                                    sectionlist=self.entry.sectionlist,
                                    sections=self.entry.sections,
                                    section_start_lines=self.entry.section_start_lines,
                                    purpose=self.entry.declaration_purpose,
                                    func_macro=func_macro)
        else:
            self.output_declaration(decl_type, declaration_name,
                                    function=declaration_name,
                                    typedef=False,
                                    functiontype=return_type,
                                    parameterlist=self.entry.parameterlist,
                                    parameterdescs=self.entry.parameterdescs,
                                    parametertypes=self.entry.parametertypes,
                                    parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
                                    sectionlist=self.entry.sectionlist,
                                    sections=self.entry.sections,
                                    section_start_lines=self.entry.section_start_lines,
                                    purpose=self.entry.declaration_purpose,
                                    func_macro=func_macro)

    def dump_typedef(self, ln, proto):
        """
        Stores a typedef inside self.entries array.
        """

        typedef_type = r'((?:\s+[\w\*]+\b){0,7}\s+(?:\w+\b|\*+))\s*'
        typedef_ident = r'\*?\s*(\w\S+)\s*'
        typedef_args = r'\s*\((.*)\);'

        typedef1 = KernRe(r'typedef' + typedef_type + r'\(' + typedef_ident + r'\)' + typedef_args)
        typedef2 = KernRe(r'typedef' + typedef_type + typedef_ident + typedef_args)

        # Strip comments
        proto = KernRe(r'/\*.*?\*/', flags=re.S).sub('', proto)

        # Parse function typedef prototypes
        for r in [typedef1, typedef2]:
            if not r.match(proto):
                continue

            return_type = r.group(1).strip()
            declaration_name = r.group(2)
            args = r.group(3)

            if self.entry.identifier != declaration_name:
                self.emit_warning(ln,
                                  f"expecting prototype for typedef {self.entry.identifier}. Prototype was for typedef {declaration_name} instead\n")
                return

            decl_type = 'function'
            self.create_parameter_list(ln, decl_type, args, ',', declaration_name)

            self.output_declaration(decl_type, declaration_name,
                                    function=declaration_name,
                                    typedef=True,
                                    functiontype=return_type,
                                    parameterlist=self.entry.parameterlist,
                                    parameterdescs=self.entry.parameterdescs,
                                    parametertypes=self.entry.parametertypes,
                                    parameterdesc_start_lines=self.entry.parameterdesc_start_lines,
                                    sectionlist=self.entry.sectionlist,
                                    sections=self.entry.sections,
                                    section_start_lines=self.entry.section_start_lines,
                                    purpose=self.entry.declaration_purpose)
            return

        # Handle nested parentheses or brackets
        r = KernRe(r'(\(*.\)\s*|\[*.\]\s*);$')
        while r.search(proto):
            proto = r.sub('', proto)

        # Parse simple typedefs
        r = KernRe(r'typedef.*\s+(\w+)\s*;')
        if r.match(proto):
            declaration_name = r.group(1)

            if self.entry.identifier != declaration_name:
                self.emit_warning(ln, f"expecting prototype for typedef {self.entry.identifier}. Prototype was for typedef {declaration_name} instead\n")
                return

            self.output_declaration('typedef', declaration_name,
                                    typedef=declaration_name,
                                    sectionlist=self.entry.sectionlist,
                                    sections=self.entry.sections,
                                    section_start_lines=self.entry.section_start_lines,
                                    purpose=self.entry.declaration_purpose)
            return

        self.emit_warning(ln, "error: Cannot parse typedef!")

    @staticmethod
    def process_export(function_set, line):
        """
        process EXPORT_SYMBOL* tags

        This method doesn't use any variable from the class, so declare it
        with a staticmethod decorator.
        """

        # Note: it accepts only one EXPORT_SYMBOL* per line, as having
        # multiple export lines would violate Kernel coding style.

        if export_symbol.search(line):
            symbol = export_symbol.group(2)
            function_set.add(symbol)
            return

        if export_symbol_ns.search(line):
            symbol = export_symbol_ns.group(2)
            function_set.add(symbol)

    def process_normal(self, ln, line):
        """
        STATE_NORMAL: looking for the /** to begin everything.
        """

        if not doc_start.match(line):
            return

        # start a new entry
        self.reset_state(ln)
        self.entry.in_doc_sect = False

        # next line is always the function name
        self.state = self.STATE_NAME

    def process_name(self, ln, line):
        """
        STATE_NAME: Looking for the "name - description" line
        """

        if doc_block.search(line):
            self.entry.new_start_line = ln

            if not doc_block.group(1):
                self.entry.section = self.section_intro
            else:
                self.entry.section = doc_block.group(1)

            self.entry.identifier = self.entry.section
            self.state = self.STATE_DOCBLOCK
            return

        if doc_decl.search(line):
            self.entry.identifier = doc_decl.group(1)
            self.entry.is_kernel_comment = False

            decl_start = str(doc_com)       # comment block asterisk
            fn_type = r"(?:\w+\s*\*\s*)?"  # type (for non-functions)
            parenthesis = r"(?:\(\w*\))?"   # optional parenthesis on function
            decl_end = r"(?:[-:].*)"         # end of the name part

            # test for pointer declaration type, foo * bar() - desc
            r = KernRe(fr"^{decl_start}([\w\s]+?){parenthesis}?\s*{decl_end}?$")
            if r.search(line):
                self.entry.identifier = r.group(1)

            # Test for data declaration
            r = KernRe(r"^\s*\*?\s*(struct|union|enum|typedef)\b\s*(\w*)")
            if r.search(line):
                self.entry.decl_type = r.group(1)
                self.entry.identifier = r.group(2)
                self.entry.is_kernel_comment = True
            else:
                # Look for foo() or static void foo() - description;
                # or misspelt identifier

                r1 = KernRe(fr"^{decl_start}{fn_type}(\w+)\s*{parenthesis}\s*{decl_end}?$")
                r2 = KernRe(fr"^{decl_start}{fn_type}(\w+[^-:]*){parenthesis}\s*{decl_end}$")

                for r in [r1, r2]:
                    if r.search(line):
                        self.entry.identifier = r.group(1)
                        self.entry.decl_type = "function"

                        r = KernRe(r"define\s+")
                        self.entry.identifier = r.sub("", self.entry.identifier)
                        self.entry.is_kernel_comment = True
                        break

            self.entry.identifier = self.entry.identifier.strip(" ")

            self.state = self.STATE_BODY

            # if there's no @param blocks need to set up default section here
            self.entry.section = self.section_default
            self.entry.new_start_line = ln + 1

            r = KernRe("[-:](.*)")
            if r.search(line):
                # strip leading/trailing/multiple spaces
                self.entry.descr = r.group(1).strip(" ")

                r = KernRe(r"\s+")
                self.entry.descr = r.sub(" ", self.entry.descr)
                self.entry.declaration_purpose = self.entry.descr
                self.state = self.STATE_BODY_MAYBE
            else:
                self.entry.declaration_purpose = ""

            if not self.entry.is_kernel_comment:
                self.emit_warning(ln,
                                  f"This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst\n{line}")
                self.state = self.STATE_NORMAL

            if not self.entry.declaration_purpose and self.config.wshort_desc:
                self.emit_warning(ln,
                                  f"missing initial short description on line:\n{line}")

            if not self.entry.identifier and self.entry.decl_type != "enum":
                self.emit_warning(ln,
                                  f"wrong kernel-doc identifier on line:\n{line}")
                self.state = self.STATE_NORMAL

            if self.config.verbose:
                self.emit_warning(ln,
                                  f"Scanning doc for {self.entry.decl_type} {self.entry.identifier}",
                                  warning=False)

            return

        # Failed to find an identifier. Emit a warning
        self.emit_warning(ln, f"Cannot find identifier on line:\n{line}")

    def process_body(self, ln, line):
        """
        STATE_BODY and STATE_BODY_MAYBE: the bulk of a kerneldoc comment.
        """

        if self.state == self.STATE_BODY_WITH_BLANK_LINE:
            r = KernRe(r"\s*\*\s?\S")
            if r.match(line):
                self.dump_section()
                self.entry.section = self.section_default
                self.entry.new_start_line = ln
                self.entry.contents = ""

        if doc_sect.search(line):
            self.entry.in_doc_sect = True
            newsection = doc_sect.group(1)

            if newsection.lower() in ["description", "context"]:
                newsection = newsection.title()

            # Special case: @return is a section, not a param description
            if newsection.lower() in ["@return", "@returns",
                                      "return", "returns"]:
                newsection = "Return"

            # Perl kernel-doc has a check here for contents before sections.
            # the logic there is always false, as in_doc_sect variable is
            # always true. So, just don't implement Wcontents_before_sections

            # .title()
            newcontents = doc_sect.group(2)
            if not newcontents:
                newcontents = ""

            if self.entry.contents.strip("\n"):
                self.dump_section()

            self.entry.new_start_line = ln
            self.entry.section = newsection
            self.entry.leading_space = None

            self.entry.contents = newcontents.lstrip()
            if self.entry.contents:
                self.entry.contents += "\n"

            self.state = self.STATE_BODY
            return

        if doc_end.search(line):
            self.dump_section()

            # Look for doc_com + <text> + doc_end:
            r = KernRe(r'\s*\*\s*[a-zA-Z_0-9:\.]+\*/')
            if r.match(line):
                self.emit_warning(ln, f"suspicious ending line: {line}")

            self.entry.prototype = ""
            self.entry.new_start_line = ln + 1

            self.state = self.STATE_PROTO
            return

        if doc_content.search(line):
            cont = doc_content.group(1)

            if cont == "":
                if self.entry.section == self.section_context:
                    self.dump_section()

                    self.entry.new_start_line = ln
                    self.state = self.STATE_BODY
                else:
                    if self.entry.section != self.section_default:
                        self.state = self.STATE_BODY_WITH_BLANK_LINE
                    else:
                        self.state = self.STATE_BODY

                    self.entry.contents += "\n"

            elif self.state == self.STATE_BODY_MAYBE:

                # Continued declaration purpose
                self.entry.declaration_purpose = self.entry.declaration_purpose.rstrip()
                self.entry.declaration_purpose += " " + cont

                r = KernRe(r"\s+")
                self.entry.declaration_purpose = r.sub(' ',
                                                       self.entry.declaration_purpose)

            else:
                if self.entry.section.startswith('@') or        \
                   self.entry.section == self.section_context:
                    if self.entry.leading_space is None:
                        r = KernRe(r'^(\s+)')
                        if r.match(cont):
                            self.entry.leading_space = len(r.group(1))
                        else:
                            self.entry.leading_space = 0

                    # Double-check if leading space are realy spaces
                    pos = 0
                    for i in range(0, self.entry.leading_space):
                        if cont[i] != " ":
                            break
                        pos += 1

                    cont = cont[pos:]

                    # NEW LOGIC:
                    # In case it is different, update it
                    if self.entry.leading_space != pos:
                        self.entry.leading_space = pos

                self.entry.contents += cont + "\n"
            return

        # Unknown line, ignore
        self.emit_warning(ln, f"bad line: {line}")

    def process_inline(self, ln, line):
        """STATE_INLINE: docbook comments within a prototype."""

        if self.inline_doc_state == self.STATE_INLINE_NAME and \
           doc_inline_sect.search(line):
            self.entry.section = doc_inline_sect.group(1)
            self.entry.new_start_line = ln

            self.entry.contents = doc_inline_sect.group(2).lstrip()
            if self.entry.contents != "":
                self.entry.contents += "\n"

            self.inline_doc_state = self.STATE_INLINE_TEXT
            # Documentation block end */
            return

        if doc_inline_end.search(line):
            if self.entry.contents not in ["", "\n"]:
                self.dump_section()

            self.state = self.STATE_PROTO
            self.inline_doc_state = self.STATE_INLINE_NA
            return

        if doc_content.search(line):
            if self.inline_doc_state == self.STATE_INLINE_TEXT:
                self.entry.contents += doc_content.group(1) + "\n"
                if not self.entry.contents.strip(" ").rstrip("\n"):
                    self.entry.contents = ""

            elif self.inline_doc_state == self.STATE_INLINE_NAME:
                self.emit_warning(ln,
                                  f"Incorrect use of kernel-doc format: {line}")

                self.inline_doc_state = self.STATE_INLINE_ERROR

    def syscall_munge(self, ln, proto):         # pylint: disable=W0613
        """
        Handle syscall definitions
        """

        is_void = False

        # Strip newlines/CR's
        proto = re.sub(r'[\r\n]+', ' ', proto)

        # Check if it's a SYSCALL_DEFINE0
        if 'SYSCALL_DEFINE0' in proto:
            is_void = True

        # Replace SYSCALL_DEFINE with correct return type & function name
        proto = KernRe(r'SYSCALL_DEFINE.*\(').sub('long sys_', proto)

        r = KernRe(r'long\s+(sys_.*?),')
        if r.search(proto):
            proto = KernRe(',').sub('(', proto, count=1)
        elif is_void:
            proto = KernRe(r'\)').sub('(void)', proto, count=1)

        # Now delete all of the odd-numbered commas in the proto
        # so that argument types & names don't have a comma between them
        count = 0
        length = len(proto)

        if is_void:
            length = 0  # skip the loop if is_void

        for ix in range(length):
            if proto[ix] == ',':
                count += 1
                if count % 2 == 1:
                    proto = proto[:ix] + ' ' + proto[ix + 1:]

        return proto

    def tracepoint_munge(self, ln, proto):
        """
        Handle tracepoint definitions
        """

        tracepointname = None
        tracepointargs = None

        # Match tracepoint name based on different patterns
        r = KernRe(r'TRACE_EVENT\((.*?),')
        if r.search(proto):
            tracepointname = r.group(1)

        r = KernRe(r'DEFINE_SINGLE_EVENT\((.*?),')
        if r.search(proto):
            tracepointname = r.group(1)

        r = KernRe(r'DEFINE_EVENT\((.*?),(.*?),')
        if r.search(proto):
            tracepointname = r.group(2)

        if tracepointname:
            tracepointname = tracepointname.lstrip()

        r = KernRe(r'TP_PROTO\((.*?)\)')
        if r.search(proto):
            tracepointargs = r.group(1)

        if not tracepointname or not tracepointargs:
            self.emit_warning(ln,
                              f"Unrecognized tracepoint format:\n{proto}\n")
        else:
            proto = f"static inline void trace_{tracepointname}({tracepointargs})"
            self.entry.identifier = f"trace_{self.entry.identifier}"

        return proto

    def process_proto_function(self, ln, line):
        """Ancillary routine to process a function prototype"""

        # strip C99-style comments to end of line
        r = KernRe(r"\/\/.*$", re.S)
        line = r.sub('', line)

        if KernRe(r'\s*#\s*define').match(line):
            self.entry.prototype = line
        elif line.startswith('#'):
            # Strip other macros like #ifdef/#ifndef/#endif/...
            pass
        else:
            r = KernRe(r'([^\{]*)')
            if r.match(line):
                self.entry.prototype += r.group(1) + " "

        if '{' in line or ';' in line or KernRe(r'\s*#\s*define').match(line):
            # strip comments
            r = KernRe(r'/\*.*?\*/')
            self.entry.prototype = r.sub('', self.entry.prototype)

            # strip newlines/cr's
            r = KernRe(r'[\r\n]+')
            self.entry.prototype = r.sub(' ', self.entry.prototype)

            # strip leading spaces
            r = KernRe(r'^\s+')
            self.entry.prototype = r.sub('', self.entry.prototype)

            # Handle self.entry.prototypes for function pointers like:
            #       int (*pcs_config)(struct foo)

            r = KernRe(r'^(\S+\s+)\(\s*\*(\S+)\)')
            self.entry.prototype = r.sub(r'\1\2', self.entry.prototype)

            if 'SYSCALL_DEFINE' in self.entry.prototype:
                self.entry.prototype = self.syscall_munge(ln,
                                                          self.entry.prototype)

            r = KernRe(r'TRACE_EVENT|DEFINE_EVENT|DEFINE_SINGLE_EVENT')
            if r.search(self.entry.prototype):
                self.entry.prototype = self.tracepoint_munge(ln,
                                                             self.entry.prototype)

            self.dump_function(ln, self.entry.prototype)
            self.reset_state(ln)

    def process_proto_type(self, ln, line):
        """Ancillary routine to process a type"""

        # Strip newlines/cr's.
        line = KernRe(r'[\r\n]+', re.S).sub(' ', line)

        # Strip leading spaces
        line = KernRe(r'^\s+', re.S).sub('', line)

        # Strip trailing spaces
        line = KernRe(r'\s+$', re.S).sub('', line)

        # Strip C99-style comments to the end of the line
        line = KernRe(r"\/\/.*$", re.S).sub('', line)

        # To distinguish preprocessor directive from regular declaration later.
        if line.startswith('#'):
            line += ";"

        r = KernRe(r'([^\{\};]*)([\{\};])(.*)')
        while True:
            if r.search(line):
                if self.entry.prototype:
                    self.entry.prototype += " "
                self.entry.prototype += r.group(1) + r.group(2)

                self.entry.brcount += r.group(2).count('{')
                self.entry.brcount -= r.group(2).count('}')

                self.entry.brcount = max(self.entry.brcount, 0)

                if r.group(2) == ';' and self.entry.brcount == 0:
                    self.dump_declaration(ln, self.entry.prototype)
                    self.reset_state(ln)
                    break

                line = r.group(3)
            else:
                self.entry.prototype += line
                break

    def process_proto(self, ln, line):
        """STATE_PROTO: reading a function/whatever prototype."""

        if doc_inline_oneline.search(line):
            self.entry.section = doc_inline_oneline.group(1)
            self.entry.contents = doc_inline_oneline.group(2)

            if self.entry.contents != "":
                self.entry.contents += "\n"
                self.dump_section(start_new=False)

        elif doc_inline_start.search(line):
            self.state = self.STATE_INLINE
            self.inline_doc_state = self.STATE_INLINE_NAME

        elif self.entry.decl_type == 'function':
            self.process_proto_function(ln, line)

        else:
            self.process_proto_type(ln, line)

    def process_docblock(self, ln, line):
        """STATE_DOCBLOCK: within a DOC: block."""

        if doc_end.search(line):
            self.dump_section()
            self.output_declaration("doc", self.entry.identifier,
                                    sectionlist=self.entry.sectionlist,
                                    sections=self.entry.sections,
                                    section_start_lines=self.entry.section_start_lines)
            self.reset_state(ln)

        elif doc_content.search(line):
            self.entry.contents += doc_content.group(1) + "\n"

    def parse_export(self):
        """
        Parses EXPORT_SYMBOL* macros from a single Kernel source file.
        """

        export_table = set()

        try:
            with open(self.fname, "r", encoding="utf8",
                      errors="backslashreplace") as fp:

                for line in fp:
                    self.process_export(export_table, line)

        except IOError:
            return None

        return export_table

    def parse_kdoc(self):
        """
        Open and process each line of a C source file.
        The parsing is controlled via a state machine, and the line is passed
        to a different process function depending on the state. The process
        function may update the state as needed.

        Besides parsing kernel-doc tags, it also parses export symbols.
        """

        cont = False
        prev = ""
        prev_ln = None
        export_table = set()

        try:
            with open(self.fname, "r", encoding="utf8",
                      errors="backslashreplace") as fp:
                for ln, line in enumerate(fp):

                    line = line.expandtabs().strip("\n")

                    # Group continuation lines on prototypes
                    if self.state == self.STATE_PROTO:
                        if line.endswith("\\"):
                            prev += line.rstrip("\\")
                            cont = True

                            if not prev_ln:
                                prev_ln = ln

                            continue

                        if cont:
                            ln = prev_ln
                            line = prev + line
                            prev = ""
                            cont = False
                            prev_ln = None

                    self.config.log.debug("%d %s%s: %s",
                                          ln, self.st_name[self.state],
                                          self.st_inline_name[self.inline_doc_state],
                                          line)

                    # This is an optimization over the original script.
                    # There, when export_file was used for the same file,
                    # it was read twice. Here, we use the already-existing
                    # loop to parse exported symbols as well.
                    #
                    # TODO: It should be noticed that not all states are
                    # needed here. On a future cleanup, process export only
                    # at the states that aren't handling comment markups.
                    self.process_export(export_table, line)

                    # Hand this line to the appropriate state handler
                    if self.state == self.STATE_NORMAL:
                        self.process_normal(ln, line)
                    elif self.state == self.STATE_NAME:
                        self.process_name(ln, line)
                    elif self.state in [self.STATE_BODY, self.STATE_BODY_MAYBE,
                                        self.STATE_BODY_WITH_BLANK_LINE]:
                        self.process_body(ln, line)
                    elif self.state == self.STATE_INLINE:  # scanning for inline parameters
                        self.process_inline(ln, line)
                    elif self.state == self.STATE_PROTO:
                        self.process_proto(ln, line)
                    elif self.state == self.STATE_DOCBLOCK:
                        self.process_docblock(ln, line)
        except OSError:
            self.config.log.error(f"Error: Cannot open file {self.fname}")

        return export_table, self.entries