wasi_virt_layer 0.2.13

A virtual layer for WASI modules
Documentation
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
#![allow(non_camel_case_types)]
/// Copy from wasi crate
/// Using them directly causes
/// link errors when not targeting wasi,
/// so I'm copying them after omitting those parts.

/// Special `Dircookie` value indicating the start of a directory.
pub const DIRCOOKIE_START: Dircookie = 0;

/// The "standard input" descriptor number.
pub const FD_STDIN: Fd = 0;

/// The "standard output" descriptor number.
pub const FD_STDOUT: Fd = 1;

/// The "standard error" descriptor number.
pub const FD_STDERR: Fd = 2;

use core::fmt;
/// Buffer size.
pub type Size = usize;
/// File size.
pub type Filesize = u64;
/// Timestamp in nanoseconds.
pub type Timestamp = u64;
#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// Identifier for a clock.
pub struct Clockid(u32);
/// The clock measuring real time. Time value zero corresponds with
/// 1970-01-01T00:00:00Z.
pub const CLOCKID_REALTIME: Clockid = Clockid(0);
/// The store-wide monotonic clock, which is defined as a clock measuring
/// real time, whose value cannot be adjusted and which cannot have negative
/// clock jumps. The epoch of this clock is undefined. The absolute time
/// value of this clock therefore has no meaning.
pub const CLOCKID_MONOTONIC: Clockid = Clockid(1);
/// The CPU-time clock associated with the current process.
pub const CLOCKID_PROCESS_CPUTIME_ID: Clockid = Clockid(2);
/// The CPU-time clock associated with the current thread.
pub const CLOCKID_THREAD_CPUTIME_ID: Clockid = Clockid(3);
impl Clockid {
    /// Returns the raw underlying value of the clock identifier.
    pub const fn raw(&self) -> u32 {
        self.0
    }

    /// Returns the name of the clock identifier as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "REALTIME",
            1 => "MONOTONIC",
            2 => "PROCESS_CPUTIME_ID",
            3 => "THREAD_CPUTIME_ID",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the clock identifier.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => {
                "The clock measuring real time. Time value zero corresponds with
1970-01-01T00:00:00Z."
            }
            1 => {
                "The store-wide monotonic clock, which is defined as a clock measuring
real time, whose value cannot be adjusted and which cannot have negative
clock jumps. The epoch of this clock is undefined. The absolute time
value of this clock therefore has no meaning."
            }
            2 => "The CPU-time clock associated with the current process.",
            3 => "The CPU-time clock associated with the current thread.",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Clockid {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Clockid")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// Error codes returned by functions.
pub struct Errno(u16);
/// No error occurred. System call completed successfully.
pub const ERRNO_SUCCESS: Errno = Errno(0);
/// Argument list too long.
pub const ERRNO_2BIG: Errno = Errno(1);
/// Permission denied.
pub const ERRNO_ACCES: Errno = Errno(2);
/// Address in use.
pub const ERRNO_ADDRINUSE: Errno = Errno(3);
/// Address not available.
pub const ERRNO_ADDRNOTAVAIL: Errno = Errno(4);
/// Address family not supported.
pub const ERRNO_AFNOSUPPORT: Errno = Errno(5);
/// Resource unavailable, or operation would block.
pub const ERRNO_AGAIN: Errno = Errno(6);
/// Connection already in progress.
pub const ERRNO_ALREADY: Errno = Errno(7);
/// Bad file descriptor.
pub const ERRNO_BADF: Errno = Errno(8);
/// Bad message.
pub const ERRNO_BADMSG: Errno = Errno(9);
/// Device or resource busy.
pub const ERRNO_BUSY: Errno = Errno(10);
/// Operation canceled.
pub const ERRNO_CANCELED: Errno = Errno(11);
/// No child processes.
pub const ERRNO_CHILD: Errno = Errno(12);
/// Connection aborted.
pub const ERRNO_CONNABORTED: Errno = Errno(13);
/// Connection refused.
pub const ERRNO_CONNREFUSED: Errno = Errno(14);
/// Connection reset.
pub const ERRNO_CONNRESET: Errno = Errno(15);
/// Resource deadlock would occur.
pub const ERRNO_DEADLK: Errno = Errno(16);
/// Destination address required.
pub const ERRNO_DESTADDRREQ: Errno = Errno(17);
/// Mathematics argument out of domain of function.
pub const ERRNO_DOM: Errno = Errno(18);
/// Reserved.
pub const ERRNO_DQUOT: Errno = Errno(19);
/// File exists.
pub const ERRNO_EXIST: Errno = Errno(20);
/// Bad address.
pub const ERRNO_FAULT: Errno = Errno(21);
/// File too large.
pub const ERRNO_FBIG: Errno = Errno(22);
/// Host is unreachable.
pub const ERRNO_HOSTUNREACH: Errno = Errno(23);
/// Identifier removed.
pub const ERRNO_IDRM: Errno = Errno(24);
/// Illegal byte sequence.
pub const ERRNO_ILSEQ: Errno = Errno(25);
/// Operation in progress.
pub const ERRNO_INPROGRESS: Errno = Errno(26);
/// Interrupted function.
pub const ERRNO_INTR: Errno = Errno(27);
/// Invalid argument.
pub const ERRNO_INVAL: Errno = Errno(28);
/// I/O error.
pub const ERRNO_IO: Errno = Errno(29);
/// Socket is connected.
pub const ERRNO_ISCONN: Errno = Errno(30);
/// Is a directory.
pub const ERRNO_ISDIR: Errno = Errno(31);
/// Too many levels of symbolic links.
pub const ERRNO_LOOP: Errno = Errno(32);
/// File descriptor value too large.
pub const ERRNO_MFILE: Errno = Errno(33);
/// Too many links.
pub const ERRNO_MLINK: Errno = Errno(34);
/// Message too large.
pub const ERRNO_MSGSIZE: Errno = Errno(35);
/// Reserved.
pub const ERRNO_MULTIHOP: Errno = Errno(36);
/// Filename too long.
pub const ERRNO_NAMETOOLONG: Errno = Errno(37);
/// Network is down.
pub const ERRNO_NETDOWN: Errno = Errno(38);
/// Connection aborted by network.
pub const ERRNO_NETRESET: Errno = Errno(39);
/// Network unreachable.
pub const ERRNO_NETUNREACH: Errno = Errno(40);
/// Too many files open in system.
pub const ERRNO_NFILE: Errno = Errno(41);
/// No buffer space available.
pub const ERRNO_NOBUFS: Errno = Errno(42);
/// No such device.
pub const ERRNO_NODEV: Errno = Errno(43);
/// No such file or directory.
pub const ERRNO_NOENT: Errno = Errno(44);
/// Executable file format error.
pub const ERRNO_NOEXEC: Errno = Errno(45);
/// No locks available.
pub const ERRNO_NOLCK: Errno = Errno(46);
/// Reserved.
pub const ERRNO_NOLINK: Errno = Errno(47);
/// Not enough space.
pub const ERRNO_NOMEM: Errno = Errno(48);
/// No message of the desired type.
pub const ERRNO_NOMSG: Errno = Errno(49);
/// Protocol not available.
pub const ERRNO_NOPROTOOPT: Errno = Errno(50);
/// No space left on device.
pub const ERRNO_NOSPC: Errno = Errno(51);
/// Function not supported.
pub const ERRNO_NOSYS: Errno = Errno(52);
/// The socket is not connected.
pub const ERRNO_NOTCONN: Errno = Errno(53);
/// Not a directory or a symbolic link to a directory.
pub const ERRNO_NOTDIR: Errno = Errno(54);
/// Directory not empty.
pub const ERRNO_NOTEMPTY: Errno = Errno(55);
/// State not recoverable.
pub const ERRNO_NOTRECOVERABLE: Errno = Errno(56);
/// Not a socket.
pub const ERRNO_NOTSOCK: Errno = Errno(57);
/// Not supported, or operation not supported on socket.
pub const ERRNO_NOTSUP: Errno = Errno(58);
/// Inappropriate I/O control operation.
pub const ERRNO_NOTTY: Errno = Errno(59);
/// No such device or address.
pub const ERRNO_NXIO: Errno = Errno(60);
/// Value too large to be stored in data type.
pub const ERRNO_OVERFLOW: Errno = Errno(61);
/// Previous owner died.
pub const ERRNO_OWNERDEAD: Errno = Errno(62);
/// Operation not permitted.
pub const ERRNO_PERM: Errno = Errno(63);
/// Broken pipe.
pub const ERRNO_PIPE: Errno = Errno(64);
/// Protocol error.
pub const ERRNO_PROTO: Errno = Errno(65);
/// Protocol not supported.
pub const ERRNO_PROTONOSUPPORT: Errno = Errno(66);
/// Protocol wrong type for socket.
pub const ERRNO_PROTOTYPE: Errno = Errno(67);
/// Result too large.
pub const ERRNO_RANGE: Errno = Errno(68);
/// Read-only file system.
pub const ERRNO_ROFS: Errno = Errno(69);
/// Invalid seek.
pub const ERRNO_SPIPE: Errno = Errno(70);
/// No such process.
pub const ERRNO_SRCH: Errno = Errno(71);
/// Reserved.
pub const ERRNO_STALE: Errno = Errno(72);
/// Connection timed out.
pub const ERRNO_TIMEDOUT: Errno = Errno(73);
/// Text file busy.
pub const ERRNO_TXTBSY: Errno = Errno(74);
/// Cross-device link.
pub const ERRNO_XDEV: Errno = Errno(75);
/// Extension: Capabilities insufficient.
pub const ERRNO_NOTCAPABLE: Errno = Errno(76);
impl Errno {
    /// Returns the raw underlying value of the error code.
    pub const fn raw(&self) -> u16 {
        self.0
    }

    /// Returns the name of the error code as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "SUCCESS",
            1 => "2BIG",
            2 => "ACCES",
            3 => "ADDRINUSE",
            4 => "ADDRNOTAVAIL",
            5 => "AFNOSUPPORT",
            6 => "AGAIN",
            7 => "ALREADY",
            8 => "BADF",
            9 => "BADMSG",
            10 => "BUSY",
            11 => "CANCELED",
            12 => "CHILD",
            13 => "CONNABORTED",
            14 => "CONNREFUSED",
            15 => "CONNRESET",
            16 => "DEADLK",
            17 => "DESTADDRREQ",
            18 => "DOM",
            19 => "DQUOT",
            20 => "EXIST",
            21 => "FAULT",
            22 => "FBIG",
            23 => "HOSTUNREACH",
            24 => "IDRM",
            25 => "ILSEQ",
            26 => "INPROGRESS",
            27 => "INTR",
            28 => "INVAL",
            29 => "IO",
            30 => "ISCONN",
            31 => "ISDIR",
            32 => "LOOP",
            33 => "MFILE",
            34 => "MLINK",
            35 => "MSGSIZE",
            36 => "MULTIHOP",
            37 => "NAMETOOLONG",
            38 => "NETDOWN",
            39 => "NETRESET",
            40 => "NETUNREACH",
            41 => "NFILE",
            42 => "NOBUFS",
            43 => "NODEV",
            44 => "NOENT",
            45 => "NOEXEC",
            46 => "NOLCK",
            47 => "NOLINK",
            48 => "NOMEM",
            49 => "NOMSG",
            50 => "NOPROTOOPT",
            51 => "NOSPC",
            52 => "NOSYS",
            53 => "NOTCONN",
            54 => "NOTDIR",
            55 => "NOTEMPTY",
            56 => "NOTRECOVERABLE",
            57 => "NOTSOCK",
            58 => "NOTSUP",
            59 => "NOTTY",
            60 => "NXIO",
            61 => "OVERFLOW",
            62 => "OWNERDEAD",
            63 => "PERM",
            64 => "PIPE",
            65 => "PROTO",
            66 => "PROTONOSUPPORT",
            67 => "PROTOTYPE",
            68 => "RANGE",
            69 => "ROFS",
            70 => "SPIPE",
            71 => "SRCH",
            72 => "STALE",
            73 => "TIMEDOUT",
            74 => "TXTBSY",
            75 => "XDEV",
            76 => "NOTCAPABLE",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the error code.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => "No error occurred. System call completed successfully.",
            1 => "Argument list too long.",
            2 => "Permission denied.",
            3 => "Address in use.",
            4 => "Address not available.",
            5 => "Address family not supported.",
            6 => "Resource unavailable, or operation would block.",
            7 => "Connection already in progress.",
            8 => "Bad file descriptor.",
            9 => "Bad message.",
            10 => "Device or resource busy.",
            11 => "Operation canceled.",
            12 => "No child processes.",
            13 => "Connection aborted.",
            14 => "Connection refused.",
            15 => "Connection reset.",
            16 => "Resource deadlock would occur.",
            17 => "Destination address required.",
            18 => "Mathematics argument out of domain of function.",
            19 => "Reserved.",
            20 => "File exists.",
            21 => "Bad address.",
            22 => "File too large.",
            23 => "Host is unreachable.",
            24 => "Identifier removed.",
            25 => "Illegal byte sequence.",
            26 => "Operation in progress.",
            27 => "Interrupted function.",
            28 => "Invalid argument.",
            29 => "I/O error.",
            30 => "Socket is connected.",
            31 => "Is a directory.",
            32 => "Too many levels of symbolic links.",
            33 => "File descriptor value too large.",
            34 => "Too many links.",
            35 => "Message too large.",
            36 => "Reserved.",
            37 => "Filename too long.",
            38 => "Network is down.",
            39 => "Connection aborted by network.",
            40 => "Network unreachable.",
            41 => "Too many files open in system.",
            42 => "No buffer space available.",
            43 => "No such device.",
            44 => "No such file or directory.",
            45 => "Executable file format error.",
            46 => "No locks available.",
            47 => "Reserved.",
            48 => "Not enough space.",
            49 => "No message of the desired type.",
            50 => "Protocol not available.",
            51 => "No space left on device.",
            52 => "Function not supported.",
            53 => "The socket is not connected.",
            54 => "Not a directory or a symbolic link to a directory.",
            55 => "Directory not empty.",
            56 => "State not recoverable.",
            57 => "Not a socket.",
            58 => "Not supported, or operation not supported on socket.",
            59 => "Inappropriate I/O control operation.",
            60 => "No such device or address.",
            61 => "Value too large to be stored in data type.",
            62 => "Previous owner died.",
            63 => "Operation not permitted.",
            64 => "Broken pipe.",
            65 => "Protocol error.",
            66 => "Protocol not supported.",
            67 => "Protocol wrong type for socket.",
            68 => "Result too large.",
            69 => "Read-only file system.",
            70 => "Invalid seek.",
            71 => "No such process.",
            72 => "Reserved.",
            73 => "Connection timed out.",
            74 => "Text file busy.",
            75 => "Cross-device link.",
            76 => "Extension: Capabilities insufficient.",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Errno {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Errno")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}
impl fmt::Display for Errno {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{} (error {})", self.name(), self.0)
    }
}

#[cfg(feature = "std")]
extern crate std;
#[cfg(feature = "std")]
impl std::error::Error for Errno {}

/// File descriptor rights.
pub type Rights = u64;
/// The right to invoke `fd_datasync`.
/// If `path_open` is set, includes the right to invoke
/// `path_open` with `fdflags::dsync`.
pub const RIGHTS_FD_DATASYNC: Rights = 1 << 0;
/// The right to invoke `fd_read` and `sock_recv`.
/// If `rights::fd_seek` is set, includes the right to invoke `fd_pread`.
pub const RIGHTS_FD_READ: Rights = 1 << 1;
/// The right to invoke `fd_seek`. This flag implies `rights::fd_tell`.
pub const RIGHTS_FD_SEEK: Rights = 1 << 2;
/// The right to invoke `fd_fdstat_set_flags`.
pub const RIGHTS_FD_FDSTAT_SET_FLAGS: Rights = 1 << 3;
/// The right to invoke `fd_sync`.
/// If `path_open` is set, includes the right to invoke
/// `path_open` with `fdflags::rsync` and `fdflags::dsync`.
pub const RIGHTS_FD_SYNC: Rights = 1 << 4;
/// The right to invoke `fd_seek` in such a way that the file offset
/// remains unaltered (i.e., `whence::cur` with offset zero), or to
/// invoke `fd_tell`.
pub const RIGHTS_FD_TELL: Rights = 1 << 5;
/// The right to invoke `fd_write` and `sock_send`.
/// If `rights::fd_seek` is set, includes the right to invoke `fd_pwrite`.
pub const RIGHTS_FD_WRITE: Rights = 1 << 6;
/// The right to invoke `fd_advise`.
pub const RIGHTS_FD_ADVISE: Rights = 1 << 7;
/// The right to invoke `fd_allocate`.
pub const RIGHTS_FD_ALLOCATE: Rights = 1 << 8;
/// The right to invoke `path_create_directory`.
pub const RIGHTS_PATH_CREATE_DIRECTORY: Rights = 1 << 9;
/// If `path_open` is set, the right to invoke `path_open` with `oflags::creat`.
pub const RIGHTS_PATH_CREATE_FILE: Rights = 1 << 10;
/// The right to invoke `path_link` with the file descriptor as the
/// source directory.
pub const RIGHTS_PATH_LINK_SOURCE: Rights = 1 << 11;
/// The right to invoke `path_link` with the file descriptor as the
/// target directory.
pub const RIGHTS_PATH_LINK_TARGET: Rights = 1 << 12;
/// The right to invoke `path_open`.
pub const RIGHTS_PATH_OPEN: Rights = 1 << 13;
/// The right to invoke `fd_readdir`.
pub const RIGHTS_FD_READDIR: Rights = 1 << 14;
/// The right to invoke `path_readlink`.
pub const RIGHTS_PATH_READLINK: Rights = 1 << 15;
/// The right to invoke `path_rename` with the file descriptor as the source directory.
pub const RIGHTS_PATH_RENAME_SOURCE: Rights = 1 << 16;
/// The right to invoke `path_rename` with the file descriptor as the target directory.
pub const RIGHTS_PATH_RENAME_TARGET: Rights = 1 << 17;
/// The right to invoke `path_filestat_get`.
pub const RIGHTS_PATH_FILESTAT_GET: Rights = 1 << 18;
/// The right to change a file's size (there is no `path_filestat_set_size`).
/// If `path_open` is set, includes the right to invoke `path_open` with `oflags::trunc`.
pub const RIGHTS_PATH_FILESTAT_SET_SIZE: Rights = 1 << 19;
/// The right to invoke `path_filestat_set_times`.
pub const RIGHTS_PATH_FILESTAT_SET_TIMES: Rights = 1 << 20;
/// The right to invoke `fd_filestat_get`.
pub const RIGHTS_FD_FILESTAT_GET: Rights = 1 << 21;
/// The right to invoke `fd_filestat_set_size`.
pub const RIGHTS_FD_FILESTAT_SET_SIZE: Rights = 1 << 22;
/// The right to invoke `fd_filestat_set_times`.
pub const RIGHTS_FD_FILESTAT_SET_TIMES: Rights = 1 << 23;
/// The right to invoke `path_symlink`.
pub const RIGHTS_PATH_SYMLINK: Rights = 1 << 24;
/// The right to invoke `path_remove_directory`.
pub const RIGHTS_PATH_REMOVE_DIRECTORY: Rights = 1 << 25;
/// The right to invoke `path_unlink_file`.
pub const RIGHTS_PATH_UNLINK_FILE: Rights = 1 << 26;
/// If `rights::fd_read` is set, includes the right to invoke `poll_oneoff` to subscribe to `eventtype::fd_read`.
/// If `rights::fd_write` is set, includes the right to invoke `poll_oneoff` to subscribe to `eventtype::fd_write`.
pub const RIGHTS_POLL_FD_READWRITE: Rights = 1 << 27;
/// The right to invoke `sock_shutdown`.
pub const RIGHTS_SOCK_SHUTDOWN: Rights = 1 << 28;
/// The right to invoke `sock_accept`.
pub const RIGHTS_SOCK_ACCEPT: Rights = 1 << 29;

/// A file descriptor.
pub type Fd = u32;
#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// A scatter/gather buffer for input operations.
pub struct Iovec {
    /// The address of the buffer to be filled.
    pub buf: *mut u8,
    /// The length of the buffer to be filled.
    pub buf_len: Size,
}
#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// A scatter/gather buffer for output operations.
pub struct Ciovec {
    /// The address of the buffer to be written.
    pub buf: *const u8,
    /// The length of the buffer to be written.
    pub buf_len: Size,
}
/// An array of input buffers.
pub type IovecArray<'a> = &'a [Iovec];
/// An array of output buffers.
pub type CiovecArray<'a> = &'a [Ciovec];
/// Relative offset within a file.
pub type Filedelta = i64;
#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// Relative seeking position.
pub struct Whence(u8);
/// Seek relative to start-of-file.
pub const WHENCE_SET: Whence = Whence(0);
/// Seek relative to current position.
pub const WHENCE_CUR: Whence = Whence(1);
/// Seek relative to end-of-file.
pub const WHENCE_END: Whence = Whence(2);
impl Whence {
    /// Returns the raw underlying value of the whence identifier.
    pub const fn raw(&self) -> u8 {
        self.0
    }

    /// Returns the name of the whence identifier as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "SET",
            1 => "CUR",
            2 => "END",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the whence identifier.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => "Seek relative to start-of-file.",
            1 => "Seek relative to current position.",
            2 => "Seek relative to end-of-file.",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Whence {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Whence")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

/// A directory cookie.
pub type Dircookie = u64;
/// Length of a directory name.
pub type Dirnamlen = u32;
/// An inode number.
pub type Inode = u64;
#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// The type of a file.
pub struct Filetype(u8);
/// The type of the file descriptor or file is unknown or is different from any of the other types specified.
pub const FILETYPE_UNKNOWN: Filetype = Filetype(0);
/// The file descriptor or file refers to a block device inode.
pub const FILETYPE_BLOCK_DEVICE: Filetype = Filetype(1);
/// The file descriptor or file refers to a character device inode.
pub const FILETYPE_CHARACTER_DEVICE: Filetype = Filetype(2);
/// The file descriptor or file refers to a directory inode.
pub const FILETYPE_DIRECTORY: Filetype = Filetype(3);
/// The file descriptor or file refers to a regular file inode.
pub const FILETYPE_REGULAR_FILE: Filetype = Filetype(4);
/// The file descriptor or file refers to a datagram socket.
pub const FILETYPE_SOCKET_DGRAM: Filetype = Filetype(5);
/// The file descriptor or file refers to a byte-stream socket.
pub const FILETYPE_SOCKET_STREAM: Filetype = Filetype(6);
/// The file refers to a symbolic link inode.
pub const FILETYPE_SYMBOLIC_LINK: Filetype = Filetype(7);
impl Filetype {
    /// Returns the raw underlying value of the file type.
    pub const fn raw(&self) -> u8 {
        self.0
    }

    /// Returns the name of the file type as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "UNKNOWN",
            1 => "BLOCK_DEVICE",
            2 => "CHARACTER_DEVICE",
            3 => "DIRECTORY",
            4 => "REGULAR_FILE",
            5 => "SOCKET_DGRAM",
            6 => "SOCKET_STREAM",
            7 => "SYMBOLIC_LINK",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the file type.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => {
                "The type of the file descriptor or file is unknown or is different from any of the other types specified."
            }
            1 => "The file descriptor or file refers to a block device inode.",
            2 => "The file descriptor or file refers to a character device inode.",
            3 => "The file descriptor or file refers to a directory inode.",
            4 => "The file descriptor or file refers to a regular file inode.",
            5 => "The file descriptor or file refers to a datagram socket.",
            6 => "The file descriptor or file refers to a byte-stream socket.",
            7 => "The file refers to a symbolic link inode.",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Filetype {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Filetype")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// A directory entry.
pub struct Dirent {
    /// The offset of the next directory entry stored in this directory.
    pub d_next: Dircookie,
    /// The serial number of the file referred to by this directory entry.
    pub d_ino: Inode,
    /// The length of the name of the directory entry.
    pub d_namlen: Dirnamlen,
    /// The type of the file referred to by this directory entry.
    pub d_type: Filetype,
}
#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// File advisory information.
pub struct Advice(u8);
/// The application has no advice to give on its behavior with respect to the specified data.
pub const ADVICE_NORMAL: Advice = Advice(0);
/// The application expects to access the specified data sequentially from lower offsets to higher offsets.
pub const ADVICE_SEQUENTIAL: Advice = Advice(1);
/// The application expects to access the specified data in a random order.
pub const ADVICE_RANDOM: Advice = Advice(2);
/// The application expects to access the specified data in the near future.
pub const ADVICE_WILLNEED: Advice = Advice(3);
/// The application expects that it will not access the specified data in the near future.
pub const ADVICE_DONTNEED: Advice = Advice(4);
/// The application expects to access the specified data once and then not reuse it thereafter.
pub const ADVICE_NOREUSE: Advice = Advice(5);
impl Advice {
    /// Returns the raw underlying value of the advice.
    pub const fn raw(&self) -> u8 {
        self.0
    }

    /// Returns the name of the advice as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "NORMAL",
            1 => "SEQUENTIAL",
            2 => "RANDOM",
            3 => "WILLNEED",
            4 => "DONTNEED",
            5 => "NOREUSE",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the advice.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => {
                "The application has no advice to give on its behavior with respect to the specified data."
            }
            1 => {
                "The application expects to access the specified data sequentially from lower offsets to higher offsets."
            }
            2 => "The application expects to access the specified data in a random order.",
            3 => "The application expects to access the specified data in the near future.",
            4 => {
                "The application expects that it will not access the specified data in the near future."
            }
            5 => {
                "The application expects to access the specified data once and then not reuse it thereafter."
            }
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Advice {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Advice")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

/// Flags providing affect how a file descriptor behaves.
pub type Fdflags = u16;
/// Append mode: Data written to the file is always appended to the file's end.
pub const FDFLAGS_APPEND: Fdflags = 1 << 0;
/// Write according to synchronized I/O data integrity completion. Only the data stored in the file is synchronized.
pub const FDFLAGS_DSYNC: Fdflags = 1 << 1;
/// Non-blocking mode.
pub const FDFLAGS_NONBLOCK: Fdflags = 1 << 2;
/// Synchronized read I/O operations.
pub const FDFLAGS_RSYNC: Fdflags = 1 << 3;
/// Write according to synchronized I/O file integrity completion. In
/// addition to synchronizing the data stored in the file, the implementation
/// may also synchronously update the file's metadata.
pub const FDFLAGS_SYNC: Fdflags = 1 << 4;

#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// File descriptor statistics.
pub struct Fdstat {
    /// File type.
    pub fs_filetype: Filetype,
    /// File descriptor flags.
    pub fs_flags: Fdflags,
    /// Rights that apply to this file descriptor.
    pub fs_rights_base: Rights,
    /// Maximum set of rights that may be installed on new file descriptors that
    /// are created through this file descriptor, e.g., through `path_open`.
    pub fs_rights_inheriting: Rights,
}
/// Device ID.
pub type Device = u64;
/// Flags providing affect how file timestamps are adjusted.
pub type Fstflags = u16;
/// Adjust the last data access timestamp to the value stored in `filestat::atim`.
pub const FSTFLAGS_ATIM: Fstflags = 1 << 0;
/// Adjust the last data access timestamp to the time of clock `clockid::realtime`.
pub const FSTFLAGS_ATIM_NOW: Fstflags = 1 << 1;
/// Adjust the last data modification timestamp to the value stored in `filestat::mtim`.
pub const FSTFLAGS_MTIM: Fstflags = 1 << 2;
/// Adjust the last data modification timestamp to the time of clock `clockid::realtime`.
pub const FSTFLAGS_MTIM_NOW: Fstflags = 1 << 3;

/// Flags affecting path resolution.
pub type Lookupflags = u32;
/// As long as the resolved path corresponds to a symbolic link, it is expanded.
pub const LOOKUPFLAGS_SYMLINK_FOLLOW: Lookupflags = 1 << 0;

/// Open flags used by `path_open`.
pub type Oflags = u16;
/// Create file if it does not exist.
pub const OFLAGS_CREAT: Oflags = 1 << 0;
/// Fail if not a directory.
pub const OFLAGS_DIRECTORY: Oflags = 1 << 1;
/// Fail if file already exists.
pub const OFLAGS_EXCL: Oflags = 1 << 2;
/// Truncate file to size 0.
pub const OFLAGS_TRUNC: Oflags = 1 << 3;

/// Number of hard links to an inode.
pub type Linkcount = u64;
#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// File statistics.
pub struct Filestat {
    /// Device ID of device containing the file.
    pub dev: Device,
    /// File serial number.
    pub ino: Inode,
    /// File type.
    pub filetype: Filetype,
    /// Number of hard links to the file.
    pub nlink: Linkcount,
    /// For regular files, the file size in bytes. For symbolic links, the length in bytes of the pathname contained in the symbolic link.
    pub size: Filesize,
    /// Last data access timestamp.
    pub atim: Timestamp,
    /// Last data modification timestamp.
    pub mtim: Timestamp,
    /// Last file status change timestamp.
    pub ctim: Timestamp,
}
/// User-provided data that can be attached to subscriptions.
pub type Userdata = u64;
#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// Type of an event that can occur.
pub struct Eventtype(u8);
/// The time value of clock `subscription_clock::id` has
/// reached timestamp `subscription_clock::timeout`.
pub const EVENTTYPE_CLOCK: Eventtype = Eventtype(0);
/// File descriptor `subscription_fd_readwrite::file_descriptor` has data
/// available for reading. This event always triggers for regular files.
pub const EVENTTYPE_FD_READ: Eventtype = Eventtype(1);
/// File descriptor `subscription_fd_readwrite::file_descriptor` has capacity
/// available for writing. This event always triggers for regular files.
pub const EVENTTYPE_FD_WRITE: Eventtype = Eventtype(2);
impl Eventtype {
    /// Returns the raw underlying value of the event type.
    pub const fn raw(&self) -> u8 {
        self.0
    }

    /// Returns the name of the event type as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "CLOCK",
            1 => "FD_READ",
            2 => "FD_WRITE",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the event type.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => {
                "The time value of clock `subscription_clock::id` has
reached timestamp `subscription_clock::timeout`."
            }
            1 => {
                "File descriptor `subscription_fd_readwrite::file_descriptor` has data
available for reading. This event always triggers for regular files."
            }
            2 => {
                "File descriptor `subscription_fd_readwrite::file_descriptor` has capacity
available for writing. This event always triggers for regular files."
            }
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Eventtype {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Eventtype")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

/// Flags that can be associated with an event.
pub type Eventrwflags = u16;
/// The peer of this socket has closed or disconnected.
pub const EVENTRWFLAGS_FD_READWRITE_HANGUP: Eventrwflags = 1 << 0;

#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// Event contents for `EVENTTYPE_FD_READ` or `EVENTTYPE_FD_WRITE`.
pub struct EventFdReadwrite {
    /// The number of bytes available for reading or writing.
    pub nbytes: Filesize,
    /// The state of the file descriptor.
    pub flags: Eventrwflags,
}
#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// An occurrence of an event.
pub struct Event {
    /// User-provided value that got attached to `subscription::userdata`.
    pub userdata: Userdata,
    /// If non-zero, an error that occurred while processing the subscription request.
    pub error: Errno,
    /// The type of event that occured
    pub type_: Eventtype,
    /// The contents of the event, if it is an `eventtype::fd_read` or
    /// `eventtype::fd_write`. `eventtype::clock` events ignore this field.
    pub fd_readwrite: EventFdReadwrite,
}
/// Flags affecting a subscription to a clock.
pub type Subclockflags = u16;
/// If set, treat the timestamp provided in
/// `subscription_clock::timeout` as an absolute timestamp of clock
/// `subscription_clock::id`. If clear, treat the timestamp
/// provided in `subscription_clock::timeout` relative to the
/// current time value of clock `subscription_clock::id`.
pub const SUBCLOCKFLAGS_SUBSCRIPTION_CLOCK_ABSTIME: Subclockflags = 1 << 0;

#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// Subscription details for a clock event.
pub struct SubscriptionClock {
    /// The clock against which to compare the timestamp.
    pub id: Clockid,
    /// The absolute or relative timestamp.
    pub timeout: Timestamp,
    /// The amount of time that the implementation may wait additionally
    /// to coalesce with other events.
    pub precision: Timestamp,
    /// Flags specifying whether the timeout is absolute or relative
    pub flags: Subclockflags,
}
#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// Subscription details for a file descriptor read or write event.
pub struct SubscriptionFdReadwrite {
    /// The file descriptor on which to wait for it to become ready for reading or writing.
    pub file_descriptor: Fd,
}
#[repr(C)]
#[derive(Copy, Clone)]
/// The union of subscription contents.
pub union SubscriptionUU {
    /// Subscription details for a clock event.
    pub clock: SubscriptionClock,
    /// Subscription details for a file descriptor read event.
    pub fd_read: SubscriptionFdReadwrite,
    /// Subscription details for a file descriptor write event.
    pub fd_write: SubscriptionFdReadwrite,
}
#[repr(C)]
#[derive(Copy, Clone)]
/// A container for the type-tagged subscription union.
pub struct SubscriptionU {
    /// The type of the event.
    pub tag: u8,
    /// The subscription details.
    pub u: SubscriptionUU,
}

#[repr(C)]
#[derive(Copy, Clone)]
/// A request for an event.
pub struct Subscription {
    /// User-provided value that is attached to the subscription in the
    /// implementation and returned through `event::userdata`.
    pub userdata: Userdata,
    /// The type of the event to which to subscribe, and its contents
    pub u: SubscriptionU,
}
/// Exit code returned by processes.
pub type Exitcode = u32;
#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// Signal identifiers.
pub struct Signal(u8);
/// No signal. Note that POSIX has special semantics for `kill(pid, 0)`,
/// so this value is reserved.
pub const SIGNAL_NONE: Signal = Signal(0);
/// Hangup.
/// Action: Terminates the process.
pub const SIGNAL_HUP: Signal = Signal(1);
/// Terminate interrupt signal.
/// Action: Terminates the process.
pub const SIGNAL_INT: Signal = Signal(2);
/// Terminal quit signal.
/// Action: Terminates the process.
pub const SIGNAL_QUIT: Signal = Signal(3);
/// Illegal instruction.
/// Action: Terminates the process.
pub const SIGNAL_ILL: Signal = Signal(4);
/// Trace/breakpoint trap.
/// Action: Terminates the process.
pub const SIGNAL_TRAP: Signal = Signal(5);
/// Process abort signal.
/// Action: Terminates the process.
pub const SIGNAL_ABRT: Signal = Signal(6);
/// Access to an undefined portion of a memory object.
/// Action: Terminates the process.
pub const SIGNAL_BUS: Signal = Signal(7);
/// Erroneous arithmetic operation.
/// Action: Terminates the process.
pub const SIGNAL_FPE: Signal = Signal(8);
/// Kill.
/// Action: Terminates the process.
pub const SIGNAL_KILL: Signal = Signal(9);
/// User-defined signal 1.
/// Action: Terminates the process.
pub const SIGNAL_USR1: Signal = Signal(10);
/// Invalid memory reference.
/// Action: Terminates the process.
pub const SIGNAL_SEGV: Signal = Signal(11);
/// User-defined signal 2.
/// Action: Terminates the process.
pub const SIGNAL_USR2: Signal = Signal(12);
/// Write on a pipe with no one to read it.
/// Action: Ignored.
pub const SIGNAL_PIPE: Signal = Signal(13);
/// Alarm clock.
/// Action: Terminates the process.
pub const SIGNAL_ALRM: Signal = Signal(14);
/// Termination signal.
/// Action: Terminates the process.
pub const SIGNAL_TERM: Signal = Signal(15);
/// Child process terminated, stopped, or continued.
/// Action: Ignored.
pub const SIGNAL_CHLD: Signal = Signal(16);
/// Continue executing, if stopped.
/// Action: Continues executing, if stopped.
pub const SIGNAL_CONT: Signal = Signal(17);
/// Stop executing.
/// Action: Stops executing.
pub const SIGNAL_STOP: Signal = Signal(18);
/// Terminal stop signal.
/// Action: Stops executing.
pub const SIGNAL_TSTP: Signal = Signal(19);
/// Background process attempting read.
/// Action: Stops executing.
pub const SIGNAL_TTIN: Signal = Signal(20);
/// Background process attempting write.
/// Action: Stops executing.
pub const SIGNAL_TTOU: Signal = Signal(21);
/// High bandwidth data is available at a socket.
/// Action: Ignored.
pub const SIGNAL_URG: Signal = Signal(22);
/// CPU time limit exceeded.
/// Action: Terminates the process.
pub const SIGNAL_XCPU: Signal = Signal(23);
/// File size limit exceeded.
/// Action: Terminates the process.
pub const SIGNAL_XFSZ: Signal = Signal(24);
/// Virtual timer expired.
/// Action: Terminates the process.
pub const SIGNAL_VTALRM: Signal = Signal(25);
/// Profiling timer expired.
/// Action: Terminates the process.
pub const SIGNAL_PROF: Signal = Signal(26);
/// Window changed.
/// Action: Ignored.
pub const SIGNAL_WINCH: Signal = Signal(27);
/// I/O possible.
/// Action: Terminates the process.
pub const SIGNAL_POLL: Signal = Signal(28);
/// Power failure.
/// Action: Terminates the process.
pub const SIGNAL_PWR: Signal = Signal(29);
/// Bad system call.
/// Action: Terminates the process.
pub const SIGNAL_SYS: Signal = Signal(30);
impl Signal {
    /// Returns the raw underlying value of the signal.
    pub const fn raw(&self) -> u8 {
        self.0
    }

    /// Returns the name of the signal as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "NONE",
            1 => "HUP",
            2 => "INT",
            3 => "QUIT",
            4 => "ILL",
            5 => "TRAP",
            6 => "ABRT",
            7 => "BUS",
            8 => "FPE",
            9 => "KILL",
            10 => "USR1",
            11 => "SEGV",
            12 => "USR2",
            13 => "PIPE",
            14 => "ALRM",
            15 => "TERM",
            16 => "CHLD",
            17 => "CONT",
            18 => "STOP",
            19 => "TSTP",
            20 => "TTIN",
            21 => "TTOU",
            22 => "URG",
            23 => "XCPU",
            24 => "XFSZ",
            25 => "VTALRM",
            26 => "PROF",
            27 => "WINCH",
            28 => "POLL",
            29 => "PWR",
            30 => "SYS",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the signal.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => {
                "No signal. Note that POSIX has special semantics for `kill(pid, 0)`,
so this value is reserved."
            }
            1 => {
                "Hangup.
Action: Terminates the process."
            }
            2 => {
                "Terminate interrupt signal.
Action: Terminates the process."
            }
            3 => {
                "Terminal quit signal.
Action: Terminates the process."
            }
            4 => {
                "Illegal instruction.
Action: Terminates the process."
            }
            5 => {
                "Trace/breakpoint trap.
Action: Terminates the process."
            }
            6 => {
                "Process abort signal.
Action: Terminates the process."
            }
            7 => {
                "Access to an undefined portion of a memory object.
Action: Terminates the process."
            }
            8 => {
                "Erroneous arithmetic operation.
Action: Terminates the process."
            }
            9 => {
                "Kill.
Action: Terminates the process."
            }
            10 => {
                "User-defined signal 1.
Action: Terminates the process."
            }
            11 => {
                "Invalid memory reference.
Action: Terminates the process."
            }
            12 => {
                "User-defined signal 2.
Action: Terminates the process."
            }
            13 => {
                "Write on a pipe with no one to read it.
Action: Ignored."
            }
            14 => {
                "Alarm clock.
Action: Terminates the process."
            }
            15 => {
                "Termination signal.
Action: Terminates the process."
            }
            16 => {
                "Child process terminated, stopped, or continued.
Action: Ignored."
            }
            17 => {
                "Continue executing, if stopped.
Action: Continues executing, if stopped."
            }
            18 => {
                "Stop executing.
Action: Stops executing."
            }
            19 => {
                "Terminal stop signal.
Action: Stops executing."
            }
            20 => {
                "Background process attempting read.
Action: Stops executing."
            }
            21 => {
                "Background process attempting write.
Action: Stops executing."
            }
            22 => {
                "High bandwidth data is available at a socket.
Action: Ignored."
            }
            23 => {
                "CPU time limit exceeded.
Action: Terminates the process."
            }
            24 => {
                "File size limit exceeded.
Action: Terminates the process."
            }
            25 => {
                "Virtual timer expired.
Action: Terminates the process."
            }
            26 => {
                "Profiling timer expired.
Action: Terminates the process."
            }
            27 => {
                "Window changed.
Action: Ignored."
            }
            28 => {
                "I/O possible.
Action: Terminates the process."
            }
            29 => {
                "Power failure.
Action: Terminates the process."
            }
            30 => {
                "Bad system call.
Action: Terminates the process."
            }
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Signal {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Signal")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

/// Flags affecting how a socket receive operation behaves.
pub type Riflags = u16;
/// Returns the message without removing it from the socket's receive queue.
pub const RIFLAGS_RECV_PEEK: Riflags = 1 << 0;
/// On byte-stream sockets, block until the full amount of data can be returned.
pub const RIFLAGS_RECV_WAITALL: Riflags = 1 << 1;

/// Flags providing information about a completed socket receive operation.
pub type Roflags = u16;
/// Returned by `sock_recv`: Message data has been truncated.
pub const ROFLAGS_RECV_DATA_TRUNCATED: Roflags = 1 << 0;

/// Flags affecting how a socket send operation behaves.
pub type Siflags = u16;
/// Flags affecting how a socket is shut down.
pub type Sdflags = u8;
/// Disables further receive operations.
pub const SDFLAGS_RD: Sdflags = 1 << 0;
/// Disables further send operations.
pub const SDFLAGS_WR: Sdflags = 1 << 1;

#[repr(transparent)]
#[derive(Copy, Clone, Hash, Eq, PartialEq, Ord, PartialOrd)]
/// Type of a pre-opened resource.
pub struct Preopentype(u8);
/// A pre-opened directory.
pub const PREOPENTYPE_DIR: Preopentype = Preopentype(0);
impl Preopentype {
    /// Returns the raw underlying value of the pre-open type.
    pub const fn raw(&self) -> u8 {
        self.0
    }

    /// Returns the name of the pre-open type as a string.
    pub fn name(&self) -> &'static str {
        match self.0 {
            0 => "DIR",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
    /// Returns a descriptive message for the pre-open type.
    pub fn message(&self) -> &'static str {
        match self.0 {
            0 => "A pre-opened directory.",
            _ => unsafe { core::hint::unreachable_unchecked() },
        }
    }
}
impl fmt::Debug for Preopentype {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Preopentype")
            .field("code", &self.0)
            .field("name", &self.name())
            .field("message", &self.message())
            .finish()
    }
}

#[repr(C)]
#[derive(Copy, Clone, Debug)]
/// Information about a pre-opened directory.
pub struct PrestatDir {
    /// The length of the directory name for use with `fd_prestat_dir_name`.
    pub pr_name_len: Size,
}
#[repr(C)]
#[derive(Copy, Clone)]
/// Union of possible pre-open statistics.
pub union PrestatU {
    /// Detailed information about the pre-opened directory.
    pub dir: PrestatDir,
}
#[repr(C)]
#[derive(Copy, Clone)]
/// Statistics about a pre-opened resource.
pub struct Prestat {
    /// The type of pre-opened resource.
    pub tag: u8,
    /// Detailed information about the resource.
    pub u: PrestatU,
}

#[allow(unused)]
/// Ref https://docs.rs/wasi/0.11.1+wasi-snapshot-preview1/wasi/wasi_snapshot_preview1/index.html
/// This module contains the bindings for the WASI snapshot preview1 ABI.
pub mod wasi_snapshot_preview1 {
    /// Writes to a file descriptor.
    pub unsafe extern "C" fn fd_write(arg0: i32, arg1: i32, arg2: i32, arg3: i32) -> i32 {
        unimplemented!("wasi_snapshot_preview1::fd_write");
    }
}