summaryrefslogtreecommitdiffstats
path: root/dom/system/OSFileConstants.cpp
blob: fa7e9532af5da5686fee47197f0d9470617a0860 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/DebugOnly.h"

#include "fcntl.h"
#include "errno.h"

#include "prsystem.h"

// Short macro to get the size of a member of a
// given struct at compile time.
// t is the type of struct, m the name of the
// member:
// DOM_SIZEOF_MEMBER(struct mystruct, myint)
// will give you the size of the type of myint.
#define DOM_SIZEOF_MEMBER(t, m) sizeof(((t*)0)->m)

#if defined(XP_UNIX)
#  include "unistd.h"
#  include "dirent.h"
#  include "poll.h"
#  include "sys/stat.h"
#  if defined(XP_LINUX)
#    include <sys/prctl.h>
#    include <sys/vfs.h>
#    define statvfs statfs
#    define f_frsize f_bsize
#  else
#    include "sys/statvfs.h"
#  endif  // defined(XP_LINUX)
#  if !defined(ANDROID)
#    include "sys/wait.h"
#    include <spawn.h>
#  endif  // !defined(ANDROID)
#endif    // defined(XP_UNIX)

#if defined(XP_LINUX)
#  include <linux/fadvise.h>
#endif  // defined(XP_LINUX)

#if defined(XP_MACOSX)
#  include "copyfile.h"
#endif  // defined(XP_MACOSX)

#if defined(XP_WIN)
#  include <windows.h>
#  include <accctrl.h>

#  ifndef PATH_MAX
#    define PATH_MAX MAX_PATH
#  endif

#endif  // defined(XP_WIN)

#include "jsapi.h"
#include "jsfriendapi.h"
#include "js/friend/ErrorMessages.h"  // js::GetErrorMessage, JSMSG_*
#include "js/PropertyAndElement.h"  // JS_DefineObject, JS_DefineProperty, JS_GetProperty, JS_SetProperty
#include "BindingUtils.h"

// Used to provide information on the OS

#include "nsThreadUtils.h"
#include "nsIObserverService.h"
#include "nsIObserver.h"
#include "nsDirectoryServiceUtils.h"
#include "nsIXULRuntime.h"
#include "nsXPCOMCIDInternal.h"
#include "nsServiceManagerUtils.h"
#include "nsString.h"
#include "nsSystemInfo.h"
#include "nsDirectoryServiceDefs.h"
#include "nsXULAppAPI.h"
#include "nsAppDirectoryServiceDefs.h"
#include "mozJSModuleLoader.h"

#include "mozilla/ClearOnShutdown.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/UniquePtr.h"

#include "OSFileConstants.h"
#include "nsZipArchive.h"

#if defined(__DragonFly__) || defined(__FreeBSD__) || defined(__NetBSD__) || \
    defined(__OpenBSD__)
#  define __dd_fd dd_fd
#endif

/**
 * This module defines the basic libc constants (error numbers, open modes,
 * etc.) used by OS.File and possibly other OS-bound JavaScript libraries.
 */

namespace mozilla {

namespace {

StaticRefPtr<OSFileConstantsService> gInstance;

}  // anonymous namespace

struct OSFileConstantsService::Paths {
  /**
   * The name of the directory holding all the libraries (libxpcom, libnss,
   * etc.)
   */
  nsString libDir;
  nsString tmpDir;
  nsString profileDir;
  nsString localProfileDir;

  Paths() {
    libDir.SetIsVoid(true);
    tmpDir.SetIsVoid(true);
    profileDir.SetIsVoid(true);
    localProfileDir.SetIsVoid(true);
  }
};

/**
 * Return the path to one of the special directories.
 *
 * @param aKey The key to the special directory (e.g. "TmpD", "ProfD", ...)
 * @param aOutPath The path to the special directory. In case of error,
 * the string is set to void.
 */
nsresult GetPathToSpecialDir(const char* aKey, nsString& aOutPath) {
  nsCOMPtr<nsIFile> file;
  nsresult rv = NS_GetSpecialDirectory(aKey, getter_AddRefs(file));
  if (NS_FAILED(rv) || !file) {
    return rv;
  }

  return file->GetPath(aOutPath);
}

/**
 * In some cases, OSFileConstants may be instantiated before the
 * profile is setup. In such cases, |OS.Constants.Path.profileDir| and
 * |OS.Constants.Path.localProfileDir| are undefined. However, we want
 * to ensure that this does not break existing code, so that future
 * workers spawned after the profile is setup have these constants.
 *
 * For this purpose, we register an observer to set |mPaths->profileDir|
 * and |mPaths->localProfileDir| once the profile is setup.
 */
NS_IMETHODIMP
OSFileConstantsService::Observe(nsISupports*, const char* aTopic,
                                const char16_t*) {
  if (!mInitialized) {
    // Initialization has not taken place, something is wrong,
    // don't make things worse.
    return NS_OK;
  }

  nsresult rv =
      GetPathToSpecialDir(NS_APP_USER_PROFILE_50_DIR, mPaths->profileDir);
  if (NS_FAILED(rv)) {
    return rv;
  }
  rv = GetPathToSpecialDir(NS_APP_USER_PROFILE_LOCAL_50_DIR,
                           mPaths->localProfileDir);
  if (NS_FAILED(rv)) {
    return rv;
  }

  return NS_OK;
}

/**
 * Perform the part of initialization that can only be
 * executed on the main thread.
 */
nsresult OSFileConstantsService::InitOSFileConstants() {
  MOZ_ASSERT(NS_IsMainThread());
  if (mInitialized) {
    return NS_OK;
  }

  UniquePtr<Paths> paths(new Paths);

  // Initialize paths->libDir
  nsCOMPtr<nsIFile> file;
  nsresult rv =
      NS_GetSpecialDirectory(NS_XPCOM_LIBRARY_FILE, getter_AddRefs(file));
  if (NS_FAILED(rv)) {
    return rv;
  }

  nsCOMPtr<nsIFile> libDir;
  rv = file->GetParent(getter_AddRefs(libDir));
  if (NS_FAILED(rv)) {
    return rv;
  }

  rv = libDir->GetPath(paths->libDir);
  if (NS_FAILED(rv)) {
    return rv;
  }

  // Setup profileDir and localProfileDir immediately if possible (we
  // assume that NS_APP_USER_PROFILE_50_DIR and
  // NS_APP_USER_PROFILE_LOCAL_50_DIR are set simultaneously)
  rv = GetPathToSpecialDir(NS_APP_USER_PROFILE_50_DIR, paths->profileDir);
  if (NS_SUCCEEDED(rv)) {
    rv = GetPathToSpecialDir(NS_APP_USER_PROFILE_LOCAL_50_DIR,
                             paths->localProfileDir);
  }

  // Otherwise, delay setup of profileDir/localProfileDir until they
  // become available.
  if (NS_FAILED(rv)) {
    nsCOMPtr<nsIObserverService> obsService =
        do_GetService(NS_OBSERVERSERVICE_CONTRACTID, &rv);
    if (NS_FAILED(rv)) {
      return rv;
    }
    rv = obsService->AddObserver(this, "profile-do-change", false);
    if (NS_FAILED(rv)) {
      return rv;
    }
  }

  GetPathToSpecialDir(NS_OS_TEMP_DIR, paths->tmpDir);

  mPaths = std::move(paths);

  // Get the umask from the system-info service.
  // The property will always be present, but it will be zero on
  // non-Unix systems.
  // nsSystemInfo::gUserUmask is initialized by NS_InitXPCOM so we don't need
  // to initialize the service.
  mUserUmask = nsSystemInfo::gUserUmask;

  mInitialized = true;
  return NS_OK;
}

/**
 * Define a simple read-only property holding an integer.
 *
 * @param name The name of the constant. Used both as the JS name for the
 * constant and to access its value. Must be defined.
 *
 * Produces a |ConstantSpec|.
 */
#define INT_CONSTANT(name) \
  { #name, JS::Int32Value(name) }

/**
 * Define a simple read-only property holding an unsigned integer.
 *
 * @param name The name of the constant. Used both as the JS name for the
 * constant and to access its value. Must be defined.
 *
 * Produces a |ConstantSpec|.
 */
#define UINT_CONSTANT(name) \
  { #name, JS::NumberValue(name) }

/**
 * End marker for ConstantSpec
 */
#define PROP_END \
  { nullptr, JS::UndefinedValue() }

// Define missing constants for Android
#if !defined(S_IRGRP)
#  define S_IXOTH 0001
#  define S_IWOTH 0002
#  define S_IROTH 0004
#  define S_IRWXO 0007
#  define S_IXGRP 0010
#  define S_IWGRP 0020
#  define S_IRGRP 0040
#  define S_IRWXG 0070
#  define S_IXUSR 0100
#  define S_IWUSR 0200
#  define S_IRUSR 0400
#  define S_IRWXU 0700
#endif  // !defined(S_IRGRP)

/**
 * The properties defined in libc.
 *
 * If you extend this list of properties, please
 * separate categories ("errors", "open", etc.),
 * keep properties organized by alphabetical order
 * and #ifdef-away properties that are not portable.
 */
static const dom::ConstantSpec gLibcProperties[] = {
    // Arguments for open
    INT_CONSTANT(O_APPEND),
#if defined(O_CLOEXEC)
    INT_CONSTANT(O_CLOEXEC),
#endif  // defined(O_CLOEXEC)
    INT_CONSTANT(O_CREAT),
#if defined(O_DIRECTORY)
    INT_CONSTANT(O_DIRECTORY),
#endif  // defined(O_DIRECTORY)
#if defined(O_EVTONLY)
    INT_CONSTANT(O_EVTONLY),
#endif  // defined(O_EVTONLY)
    INT_CONSTANT(O_EXCL),
#if defined(O_EXLOCK)
    INT_CONSTANT(O_EXLOCK),
#endif  // defined(O_EXLOCK)
#if defined(O_LARGEFILE)
    INT_CONSTANT(O_LARGEFILE),
#endif  // defined(O_LARGEFILE)
#if defined(O_NOFOLLOW)
    INT_CONSTANT(O_NOFOLLOW),
#endif  // defined(O_NOFOLLOW)
#if defined(O_NONBLOCK)
    INT_CONSTANT(O_NONBLOCK),
#endif  // defined(O_NONBLOCK)
    INT_CONSTANT(O_RDONLY),
    INT_CONSTANT(O_RDWR),
#if defined(O_RSYNC)
    INT_CONSTANT(O_RSYNC),
#endif  // defined(O_RSYNC)
#if defined(O_SHLOCK)
    INT_CONSTANT(O_SHLOCK),
#endif  // defined(O_SHLOCK)
#if defined(O_SYMLINK)
    INT_CONSTANT(O_SYMLINK),
#endif  // defined(O_SYMLINK)
#if defined(O_SYNC)
    INT_CONSTANT(O_SYNC),
#endif  // defined(O_SYNC)
    INT_CONSTANT(O_TRUNC),
    INT_CONSTANT(O_WRONLY),

#if defined(FD_CLOEXEC)
    INT_CONSTANT(FD_CLOEXEC),
#endif  // defined(FD_CLOEXEC)

#if defined(AT_EACCESS)
    INT_CONSTANT(AT_EACCESS),
#endif  // defined(AT_EACCESS)
#if defined(AT_FDCWD)
    INT_CONSTANT(AT_FDCWD),
#endif  // defined(AT_FDCWD)
#if defined(AT_SYMLINK_NOFOLLOW)
    INT_CONSTANT(AT_SYMLINK_NOFOLLOW),
#endif  // defined(AT_SYMLINK_NOFOLLOW)

#if defined(POSIX_FADV_SEQUENTIAL)
    INT_CONSTANT(POSIX_FADV_SEQUENTIAL),
#endif  // defined(POSIX_FADV_SEQUENTIAL)

// access
#if defined(F_OK)
    INT_CONSTANT(F_OK),
    INT_CONSTANT(R_OK),
    INT_CONSTANT(W_OK),
    INT_CONSTANT(X_OK),
#endif  // defined(F_OK)

    // modes
    INT_CONSTANT(S_IRGRP),
    INT_CONSTANT(S_IROTH),
    INT_CONSTANT(S_IRUSR),
    INT_CONSTANT(S_IRWXG),
    INT_CONSTANT(S_IRWXO),
    INT_CONSTANT(S_IRWXU),
    INT_CONSTANT(S_IWGRP),
    INT_CONSTANT(S_IWOTH),
    INT_CONSTANT(S_IWUSR),
    INT_CONSTANT(S_IXOTH),
    INT_CONSTANT(S_IXGRP),
    INT_CONSTANT(S_IXUSR),

    // seek
    INT_CONSTANT(SEEK_CUR),
    INT_CONSTANT(SEEK_END),
    INT_CONSTANT(SEEK_SET),

#if defined(XP_UNIX)
    // poll
    INT_CONSTANT(POLLERR),
    INT_CONSTANT(POLLHUP),
    INT_CONSTANT(POLLIN),
    INT_CONSTANT(POLLNVAL),
    INT_CONSTANT(POLLOUT),

// wait
#  if defined(WNOHANG)
    INT_CONSTANT(WNOHANG),
#  endif  // defined(WNOHANG)

    // fcntl command values
    INT_CONSTANT(F_GETLK),
    INT_CONSTANT(F_SETFD),
    INT_CONSTANT(F_SETFL),
    INT_CONSTANT(F_SETLK),
    INT_CONSTANT(F_SETLKW),

    // flock type values
    INT_CONSTANT(F_RDLCK),
    INT_CONSTANT(F_WRLCK),
    INT_CONSTANT(F_UNLCK),

// splice
#  if defined(SPLICE_F_MOVE)
    INT_CONSTANT(SPLICE_F_MOVE),
#  endif  // defined(SPLICE_F_MOVE)
#  if defined(SPLICE_F_NONBLOCK)
    INT_CONSTANT(SPLICE_F_NONBLOCK),
#  endif  // defined(SPLICE_F_NONBLOCK)
#  if defined(SPLICE_F_MORE)
    INT_CONSTANT(SPLICE_F_MORE),
#  endif  // defined(SPLICE_F_MORE)
#  if defined(SPLICE_F_GIFT)
    INT_CONSTANT(SPLICE_F_GIFT),
#  endif  // defined(SPLICE_F_GIFT)
#endif    // defined(XP_UNIX)
// copyfile
#if defined(COPYFILE_DATA)
    INT_CONSTANT(COPYFILE_DATA),
    INT_CONSTANT(COPYFILE_EXCL),
    INT_CONSTANT(COPYFILE_XATTR),
    INT_CONSTANT(COPYFILE_STAT),
    INT_CONSTANT(COPYFILE_ACL),
    INT_CONSTANT(COPYFILE_MOVE),
#endif  // defined(COPYFILE_DATA)

    // error values
    INT_CONSTANT(EACCES),
    INT_CONSTANT(EAGAIN),
    INT_CONSTANT(EBADF),
    INT_CONSTANT(EEXIST),
    INT_CONSTANT(EFAULT),
    INT_CONSTANT(EFBIG),
    INT_CONSTANT(EINVAL),
    INT_CONSTANT(EINTR),
    INT_CONSTANT(EIO),
    INT_CONSTANT(EISDIR),
#if defined(ELOOP)  // not defined with VC9
    INT_CONSTANT(ELOOP),
#endif  // defined(ELOOP)
    INT_CONSTANT(EMFILE),
    INT_CONSTANT(ENAMETOOLONG),
    INT_CONSTANT(ENFILE),
    INT_CONSTANT(ENOENT),
    INT_CONSTANT(ENOMEM),
    INT_CONSTANT(ENOSPC),
    INT_CONSTANT(ENOTDIR),
    INT_CONSTANT(ENXIO),
#if defined(EOPNOTSUPP)  // not defined with VC 9
    INT_CONSTANT(EOPNOTSUPP),
#endif                  // defined(EOPNOTSUPP)
#if defined(EOVERFLOW)  // not defined with VC 9
    INT_CONSTANT(EOVERFLOW),
#endif  // defined(EOVERFLOW)
    INT_CONSTANT(EPERM),
    INT_CONSTANT(ERANGE),
    INT_CONSTANT(ENOSYS),
#if defined(ETIMEDOUT)  // not defined with VC 9
    INT_CONSTANT(ETIMEDOUT),
#endif                    // defined(ETIMEDOUT)
#if defined(EWOULDBLOCK)  // not defined with VC 9
    INT_CONSTANT(EWOULDBLOCK),
#endif  // defined(EWOULDBLOCK)
    INT_CONSTANT(EXDEV),

#if defined(DT_UNKNOWN)
    // Constants for |readdir|
    INT_CONSTANT(DT_UNKNOWN),
    INT_CONSTANT(DT_FIFO),
    INT_CONSTANT(DT_CHR),
    INT_CONSTANT(DT_DIR),
    INT_CONSTANT(DT_BLK),
    INT_CONSTANT(DT_REG),
    INT_CONSTANT(DT_LNK),
    INT_CONSTANT(DT_SOCK),
#endif  // defined(DT_UNKNOWN)

#if defined(XP_UNIX)
    // Constants for |stat|
    INT_CONSTANT(S_IFMT),
    INT_CONSTANT(S_IFIFO),
    INT_CONSTANT(S_IFCHR),
    INT_CONSTANT(S_IFDIR),
    INT_CONSTANT(S_IFBLK),
    INT_CONSTANT(S_IFREG),
    INT_CONSTANT(S_IFLNK),   // not defined on minGW
    INT_CONSTANT(S_IFSOCK),  // not defined on minGW
#endif                       // defined(XP_UNIX)

    INT_CONSTANT(PATH_MAX),

#if defined(XP_LINUX)
    // prctl options
    INT_CONSTANT(PR_CAPBSET_READ),
#endif

// Constants used to define data structures
//
// Many data structures have different fields/sizes/etc. on
// various OSes / versions of the same OS / platforms. For these
// data structures, we need to compute and export from C the size
// and, if necessary, the offset of fields, so as to be able to
// define the structure in JS.

#if defined(XP_UNIX)
    // The size of |mode_t|.
    {"OSFILE_SIZEOF_MODE_T", JS::Int32Value(sizeof(mode_t))},

    // The size of |gid_t|.
    {"OSFILE_SIZEOF_GID_T", JS::Int32Value(sizeof(gid_t))},

    // The size of |uid_t|.
    {"OSFILE_SIZEOF_UID_T", JS::Int32Value(sizeof(uid_t))},

    // The size of |time_t|.
    {"OSFILE_SIZEOF_TIME_T", JS::Int32Value(sizeof(time_t))},

    // The size of |fsblkcnt_t|.
    {"OSFILE_SIZEOF_FSBLKCNT_T", JS::Int32Value(sizeof(fsblkcnt_t))},

#  if !defined(ANDROID)
    // The size of |posix_spawn_file_actions_t|.
    {"OSFILE_SIZEOF_POSIX_SPAWN_FILE_ACTIONS_T",
     JS::Int32Value(sizeof(posix_spawn_file_actions_t))},

    // The size of |posix_spawnattr_t|.
    {"OSFILE_SIZEOF_POSIX_SPAWNATTR_T",
     JS::Int32Value(sizeof(posix_spawnattr_t))},
#  endif  // !defined(ANDROID)

    // Defining |dirent|.
    // Size
    {"OSFILE_SIZEOF_DIRENT", JS::Int32Value(sizeof(dirent))},

    // Defining |flock|.
    {"OSFILE_SIZEOF_FLOCK", JS::Int32Value(sizeof(struct flock))},
    {"OSFILE_OFFSETOF_FLOCK_L_START",
     JS::Int32Value(offsetof(struct flock, l_start))},
    {"OSFILE_OFFSETOF_FLOCK_L_LEN",
     JS::Int32Value(offsetof(struct flock, l_len))},
    {"OSFILE_OFFSETOF_FLOCK_L_PID",
     JS::Int32Value(offsetof(struct flock, l_pid))},
    {"OSFILE_OFFSETOF_FLOCK_L_TYPE",
     JS::Int32Value(offsetof(struct flock, l_type))},
    {"OSFILE_OFFSETOF_FLOCK_L_WHENCE",
     JS::Int32Value(offsetof(struct flock, l_whence))},

    // Offset of field |d_name|.
    {"OSFILE_OFFSETOF_DIRENT_D_NAME",
     JS::Int32Value(offsetof(struct dirent, d_name))},
    // An upper bound to the length of field |d_name| of struct |dirent|.
    // (may not be exact, depending on padding).
    {"OSFILE_SIZEOF_DIRENT_D_NAME",
     JS::Int32Value(sizeof(struct dirent) - offsetof(struct dirent, d_name))},

    // Defining |timeval|.
    {"OSFILE_SIZEOF_TIMEVAL", JS::Int32Value(sizeof(struct timeval))},
    {"OSFILE_OFFSETOF_TIMEVAL_TV_SEC",
     JS::Int32Value(offsetof(struct timeval, tv_sec))},
    {"OSFILE_OFFSETOF_TIMEVAL_TV_USEC",
     JS::Int32Value(offsetof(struct timeval, tv_usec))},

#  if defined(DT_UNKNOWN)
    // Position of field |d_type| in |dirent|
    // Not strictly posix, but seems defined on all platforms
    // except mingw32.
    {"OSFILE_OFFSETOF_DIRENT_D_TYPE",
     JS::Int32Value(offsetof(struct dirent, d_type))},
#  endif  // defined(DT_UNKNOWN)

// Under MacOS X and BSDs, |dirfd| is a macro rather than a
// function, so we need a little help to get it to work
#  if defined(dirfd)
    {"OSFILE_SIZEOF_DIR", JS::Int32Value(sizeof(DIR))},

    {"OSFILE_OFFSETOF_DIR_DD_FD", JS::Int32Value(offsetof(DIR, __dd_fd))},
#  endif

    // Defining |stat|

    {"OSFILE_SIZEOF_STAT", JS::Int32Value(sizeof(struct stat))},

    {"OSFILE_OFFSETOF_STAT_ST_MODE",
     JS::Int32Value(offsetof(struct stat, st_mode))},
    {"OSFILE_OFFSETOF_STAT_ST_UID",
     JS::Int32Value(offsetof(struct stat, st_uid))},
    {"OSFILE_OFFSETOF_STAT_ST_GID",
     JS::Int32Value(offsetof(struct stat, st_gid))},
    {"OSFILE_OFFSETOF_STAT_ST_SIZE",
     JS::Int32Value(offsetof(struct stat, st_size))},

#  if defined(HAVE_ST_ATIMESPEC)
    {"OSFILE_OFFSETOF_STAT_ST_ATIME",
     JS::Int32Value(offsetof(struct stat, st_atimespec))},
    {"OSFILE_OFFSETOF_STAT_ST_MTIME",
     JS::Int32Value(offsetof(struct stat, st_mtimespec))},
    {"OSFILE_OFFSETOF_STAT_ST_CTIME",
     JS::Int32Value(offsetof(struct stat, st_ctimespec))},
#  else
    {"OSFILE_OFFSETOF_STAT_ST_ATIME",
     JS::Int32Value(offsetof(struct stat, st_atime))},
    {"OSFILE_OFFSETOF_STAT_ST_MTIME",
     JS::Int32Value(offsetof(struct stat, st_mtime))},
    {"OSFILE_OFFSETOF_STAT_ST_CTIME",
     JS::Int32Value(offsetof(struct stat, st_ctime))},
#  endif  // defined(HAVE_ST_ATIME)

// Several OSes have a birthtime field. For the moment, supporting only Darwin.
#  if defined(_DARWIN_FEATURE_64_BIT_INODE)
    {"OSFILE_OFFSETOF_STAT_ST_BIRTHTIME",
     JS::Int32Value(offsetof(struct stat, st_birthtime))},
#  endif  // defined(_DARWIN_FEATURE_64_BIT_INODE)

    // Defining |statvfs|

    {"OSFILE_SIZEOF_STATVFS", JS::Int32Value(sizeof(struct statvfs))},

    // We have no guarantee how big "f_frsize" is, so we have to calculate that.
    {"OSFILE_SIZEOF_STATVFS_F_FRSIZE",
     JS::Int32Value(DOM_SIZEOF_MEMBER(struct statvfs, f_frsize))},
    {"OSFILE_OFFSETOF_STATVFS_F_FRSIZE",
     JS::Int32Value(offsetof(struct statvfs, f_frsize))},
    {"OSFILE_OFFSETOF_STATVFS_F_BAVAIL",
     JS::Int32Value(offsetof(struct statvfs, f_bavail))},

#endif  // defined(XP_UNIX)

// System configuration

// Under MacOSX, to avoid using deprecated functions that do not
// match the constants we define in this object (including
// |sizeof|/|offsetof| stuff, but not only), for a number of
// functions, we need to use functions with a $INODE64 suffix.
// That is true on Intel-based mac when the _DARWIN_FEATURE_64_BIT_INODE
// macro is set. But not on Apple Silicon.
#if defined(_DARWIN_FEATURE_64_BIT_INODE) && !defined(__aarch64__)
    {"_DARWIN_INODE64_SYMBOLS", JS::Int32Value(1)},
#endif  // defined(_DARWIN_FEATURE_64_BIT_INODE)

// Similar feature for Linux
#if defined(_STAT_VER)
    INT_CONSTANT(_STAT_VER),
#endif  // defined(_STAT_VER)

    PROP_END};

#if defined(XP_WIN)
/**
 * The properties defined in windows.h.
 *
 * If you extend this list of properties, please
 * separate categories ("errors", "open", etc.),
 * keep properties organized by alphabetical order
 * and #ifdef-away properties that are not portable.
 */
static const dom::ConstantSpec gWinProperties[] = {
    // FormatMessage flags
    INT_CONSTANT(FORMAT_MESSAGE_FROM_SYSTEM),
    INT_CONSTANT(FORMAT_MESSAGE_IGNORE_INSERTS),

    // The max length of paths
    INT_CONSTANT(MAX_PATH),

    // CreateFile desired access
    INT_CONSTANT(GENERIC_ALL),
    INT_CONSTANT(GENERIC_EXECUTE),
    INT_CONSTANT(GENERIC_READ),
    INT_CONSTANT(GENERIC_WRITE),

    // CreateFile share mode
    INT_CONSTANT(FILE_SHARE_DELETE),
    INT_CONSTANT(FILE_SHARE_READ),
    INT_CONSTANT(FILE_SHARE_WRITE),

    // CreateFile creation disposition
    INT_CONSTANT(CREATE_ALWAYS),
    INT_CONSTANT(CREATE_NEW),
    INT_CONSTANT(OPEN_ALWAYS),
    INT_CONSTANT(OPEN_EXISTING),
    INT_CONSTANT(TRUNCATE_EXISTING),

    // CreateFile attributes
    INT_CONSTANT(FILE_ATTRIBUTE_ARCHIVE),
    INT_CONSTANT(FILE_ATTRIBUTE_DIRECTORY),
    INT_CONSTANT(FILE_ATTRIBUTE_HIDDEN),
    INT_CONSTANT(FILE_ATTRIBUTE_NORMAL),
    INT_CONSTANT(FILE_ATTRIBUTE_READONLY),
    INT_CONSTANT(FILE_ATTRIBUTE_REPARSE_POINT),
    INT_CONSTANT(FILE_ATTRIBUTE_SYSTEM),
    INT_CONSTANT(FILE_ATTRIBUTE_TEMPORARY),
    INT_CONSTANT(FILE_FLAG_BACKUP_SEMANTICS),

    // CreateFile error constant
    {"INVALID_HANDLE_VALUE", JS::Int32Value(INT_PTR(INVALID_HANDLE_VALUE))},

    // CreateFile flags
    INT_CONSTANT(FILE_FLAG_DELETE_ON_CLOSE),

    // SetFilePointer methods
    INT_CONSTANT(FILE_BEGIN),
    INT_CONSTANT(FILE_CURRENT),
    INT_CONSTANT(FILE_END),

    // SetFilePointer error constant
    UINT_CONSTANT(INVALID_SET_FILE_POINTER),

    // File attributes
    INT_CONSTANT(FILE_ATTRIBUTE_DIRECTORY),

    // MoveFile flags
    INT_CONSTANT(MOVEFILE_COPY_ALLOWED),
    INT_CONSTANT(MOVEFILE_REPLACE_EXISTING),

    // GetFileAttributes error constant
    INT_CONSTANT(INVALID_FILE_ATTRIBUTES),

    // GetNamedSecurityInfo and SetNamedSecurityInfo constants
    INT_CONSTANT(UNPROTECTED_DACL_SECURITY_INFORMATION),
    INT_CONSTANT(SE_FILE_OBJECT),
    INT_CONSTANT(DACL_SECURITY_INFORMATION),

    // Errors
    INT_CONSTANT(ERROR_INVALID_HANDLE),
    INT_CONSTANT(ERROR_ACCESS_DENIED),
    INT_CONSTANT(ERROR_DIR_NOT_EMPTY),
    INT_CONSTANT(ERROR_FILE_EXISTS),
    INT_CONSTANT(ERROR_ALREADY_EXISTS),
    INT_CONSTANT(ERROR_FILE_NOT_FOUND),
    INT_CONSTANT(ERROR_NO_MORE_FILES),
    INT_CONSTANT(ERROR_PATH_NOT_FOUND),
    INT_CONSTANT(ERROR_BAD_ARGUMENTS),
    INT_CONSTANT(ERROR_SHARING_VIOLATION),
    INT_CONSTANT(ERROR_NOT_SUPPORTED),

    PROP_END};
#endif  // defined(XP_WIN)

/**
 * Get a field of an object as an object.
 *
 * If the field does not exist, create it. If it exists but is not an
 * object, throw a JS error.
 */
JSObject* GetOrCreateObjectProperty(JSContext* cx,
                                    JS::Handle<JSObject*> aObject,
                                    const char* aProperty) {
  JS::Rooted<JS::Value> val(cx);
  if (!JS_GetProperty(cx, aObject, aProperty, &val)) {
    return nullptr;
  }
  if (!val.isUndefined()) {
    if (val.isObject()) {
      return &val.toObject();
    }

    JS_ReportErrorNumberASCII(cx, js::GetErrorMessage, nullptr,
                              JSMSG_UNEXPECTED_TYPE, aProperty,
                              "not an object");
    return nullptr;
  }
  return JS_DefineObject(cx, aObject, aProperty, nullptr, JSPROP_ENUMERATE);
}

/**
 * Set a property of an object from a nsString.
 *
 * If the nsString is void (i.e. IsVoid is true), do nothing.
 */
bool SetStringProperty(JSContext* cx, JS::Handle<JSObject*> aObject,
                       const char* aProperty, const nsString aValue) {
  if (aValue.IsVoid()) {
    return true;
  }
  JSString* strValue = JS_NewUCStringCopyZ(cx, aValue.get());
  NS_ENSURE_TRUE(strValue, false);
  JS::Rooted<JS::Value> valValue(cx, JS::StringValue(strValue));
  return JS_SetProperty(cx, aObject, aProperty, valValue);
}

/**
 * Define OS-specific constants.
 *
 * This function creates or uses JS object |OS.Constants| to store
 * all its constants.
 */
bool OSFileConstantsService::DefineOSFileConstants(
    JSContext* aCx, JS::Handle<JSObject*> aGlobal) {
  if (!mInitialized) {
    JS_ReportErrorNumberASCII(aCx, js::GetErrorMessage, nullptr,
                              JSMSG_CANT_OPEN, "OSFileConstants",
                              "initialization has failed");
    return false;
  }

  JS::Rooted<JSObject*> objOS(aCx);
  if (!(objOS = GetOrCreateObjectProperty(aCx, aGlobal, "OS"))) {
    return false;
  }
  JS::Rooted<JSObject*> objConstants(aCx);
  if (!(objConstants = GetOrCreateObjectProperty(aCx, objOS, "Constants"))) {
    return false;
  }

  // Build OS.Constants.libc

  JS::Rooted<JSObject*> objLibc(aCx);
  if (!(objLibc = GetOrCreateObjectProperty(aCx, objConstants, "libc"))) {
    return false;
  }
  if (!dom::DefineConstants(aCx, objLibc, gLibcProperties)) {
    return false;
  }

#if defined(XP_WIN)
  // Build OS.Constants.Win

  JS::Rooted<JSObject*> objWin(aCx);
  if (!(objWin = GetOrCreateObjectProperty(aCx, objConstants, "Win"))) {
    return false;
  }
  if (!dom::DefineConstants(aCx, objWin, gWinProperties)) {
    return false;
  }
#endif  // defined(XP_WIN)

  // Build OS.Constants.Sys

  JS::Rooted<JSObject*> objSys(aCx);
  if (!(objSys = GetOrCreateObjectProperty(aCx, objConstants, "Sys"))) {
    return false;
  }

  nsCOMPtr<nsIXULRuntime> runtime =
      do_GetService(XULRUNTIME_SERVICE_CONTRACTID);
  if (runtime) {
    nsAutoCString os;
    DebugOnly<nsresult> rv = runtime->GetOS(os);
    MOZ_ASSERT(NS_SUCCEEDED(rv));

    JSString* strVersion = JS_NewStringCopyZ(aCx, os.get());
    if (!strVersion) {
      return false;
    }

    JS::Rooted<JS::Value> valVersion(aCx, JS::StringValue(strVersion));
    if (!JS_SetProperty(aCx, objSys, "Name", valVersion)) {
      return false;
    }
  }

#if defined(DEBUG)
  JS::Rooted<JS::Value> valDebug(aCx, JS::TrueValue());
  if (!JS_SetProperty(aCx, objSys, "DEBUG", valDebug)) {
    return false;
  }
#endif

#if defined(HAVE_64BIT_BUILD)
  JS::Rooted<JS::Value> valBits(aCx, JS::Int32Value(64));
#else
  JS::Rooted<JS::Value> valBits(aCx, JS::Int32Value(32));
#endif  // defined (HAVE_64BIT_BUILD)
  if (!JS_SetProperty(aCx, objSys, "bits", valBits)) {
    return false;
  }

  if (!JS_DefineProperty(
          aCx, objSys, "umask", mUserUmask,
          JSPROP_ENUMERATE | JSPROP_READONLY | JSPROP_PERMANENT)) {
    return false;
  }

  // Build OS.Constants.Path

  JS::Rooted<JSObject*> objPath(aCx);
  if (!(objPath = GetOrCreateObjectProperty(aCx, objConstants, "Path"))) {
    return false;
  }

  // Locate libxul
  // Note that we don't actually provide the full path, only the name of the
  // library, which is sufficient to link to the library using js-ctypes.

#if defined(XP_MACOSX)
  // Under MacOS X, for some reason, libxul is called simply "XUL",
  // and we need to provide the full path.
  nsAutoString libxul;
  libxul.Append(mPaths->libDir);
  libxul.AppendLiteral("/XUL");
#else
  // On other platforms, libxul is a library "xul" with regular
  // library prefix/suffix.
  nsAutoString libxul;
  libxul.AppendLiteral(MOZ_DLL_PREFIX);
  libxul.AppendLiteral("xul");
  libxul.AppendLiteral(MOZ_DLL_SUFFIX);
#endif  // defined(XP_MACOSX)

  if (!SetStringProperty(aCx, objPath, "libxul", libxul)) {
    return false;
  }

  if (!SetStringProperty(aCx, objPath, "libDir", mPaths->libDir)) {
    return false;
  }

  if (!SetStringProperty(aCx, objPath, "tmpDir", mPaths->tmpDir)) {
    return false;
  }

  // Configure profileDir only if it is available at this stage
  if (!mPaths->profileDir.IsVoid() &&
      !SetStringProperty(aCx, objPath, "profileDir", mPaths->profileDir)) {
    return false;
  }

  // Configure localProfileDir only if it is available at this stage
  if (!mPaths->localProfileDir.IsVoid() &&
      !SetStringProperty(aCx, objPath, "localProfileDir",
                         mPaths->localProfileDir)) {
    return false;
  }

  return true;
}

NS_IMPL_ISUPPORTS(OSFileConstantsService, nsIOSFileConstantsService,
                  nsIObserver)

/* static */
already_AddRefed<OSFileConstantsService> OSFileConstantsService::GetOrCreate() {
  if (!gInstance) {
    MOZ_ASSERT(NS_IsMainThread());

    RefPtr<OSFileConstantsService> service = new OSFileConstantsService();
    nsresult rv = service->InitOSFileConstants();
    if (NS_WARN_IF(NS_FAILED(rv))) {
      return nullptr;
    }

    gInstance = std::move(service);
    ClearOnShutdown(&gInstance);
  }

  RefPtr<OSFileConstantsService> copy = gInstance;
  return copy.forget();
}

OSFileConstantsService::OSFileConstantsService()
    : mInitialized(false), mUserUmask(0) {
  MOZ_ASSERT(NS_IsMainThread());
}

OSFileConstantsService::~OSFileConstantsService() {
  MOZ_ASSERT(NS_IsMainThread());
}

NS_IMETHODIMP
OSFileConstantsService::Init(JSContext* aCx) {
  MOZ_ASSERT(NS_IsMainThread());

  nsresult rv = InitOSFileConstants();
  if (NS_FAILED(rv)) {
    return rv;
  }

  mozJSModuleLoader* loader = mozJSModuleLoader::Get();
  JS::Rooted<JSObject*> targetObj(aCx);
  loader->FindTargetObject(aCx, &targetObj);

  if (!DefineOSFileConstants(aCx, targetObj)) {
    return NS_ERROR_FAILURE;
  }

  return NS_OK;
}

}  // namespace mozilla