summaryrefslogtreecommitdiffstats
path: root/src/common/file_util.cpp
blob: 54846378790054bbc1917cab9051b94381059933 (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
// Copyright 2013 Dolphin Emulator Project / 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <array>
#include <memory>
#include <sstream>
#include <unordered_map>
#include "common/assert.h"
#include "common/common_funcs.h"
#include "common/common_paths.h"
#include "common/file_util.h"
#include "common/logging/log.h"

#ifdef _WIN32
#include <windows.h>
// windows.h needs to be included before other windows headers
#include <commdlg.h> // for GetSaveFileName
#include <direct.h>  // getcwd
#include <io.h>
#include <shellapi.h>
#include <shlobj.h> // for SHGetFolderPath
#include <tchar.h>
#include "common/string_util.h"

// 64 bit offsets for windows
#define fseeko _fseeki64
#define ftello _ftelli64
#define atoll _atoi64
#define stat _stat64
#define fstat _fstat64
#define fileno _fileno
#else
#ifdef __APPLE__
#include <sys/param.h>
#endif
#include <cctype>
#include <cerrno>
#include <cstdlib>
#include <cstring>
#include <dirent.h>
#include <pwd.h>
#include <unistd.h>
#endif

#if defined(__APPLE__)
// CFURL contains __attribute__ directives that gcc does not know how to parse, so we need to just
// ignore them if we're not using clang. The macro is only used to prevent linking against
// functions that don't exist on older versions of macOS, and the worst case scenario is a linker
// error, so this is perfectly safe, just inconvenient.
#ifndef __clang__
#define availability(...)
#endif
#include <CoreFoundation/CFBundle.h>
#include <CoreFoundation/CFString.h>
#include <CoreFoundation/CFURL.h>
#ifdef availability
#undef availability
#endif

#endif

#include <algorithm>
#include <sys/stat.h>

#ifndef S_ISDIR
#define S_ISDIR(m) (((m)&S_IFMT) == S_IFDIR)
#endif

// This namespace has various generic functions related to files and paths.
// The code still needs a ton of cleanup.
// REMEMBER: strdup considered harmful!
namespace FileUtil {

// Remove any ending forward slashes from directory paths
// Modifies argument.
static void StripTailDirSlashes(std::string& fname) {
    if (fname.length() > 1) {
        std::size_t i = fname.length();
        while (i > 0 && fname[i - 1] == DIR_SEP_CHR)
            --i;
        fname.resize(i);
    }
    return;
}

// Returns true if file filename exists
bool Exists(const std::string& filename) {
    struct stat file_info;

    std::string copy(filename);
    StripTailDirSlashes(copy);

#ifdef _WIN32
    // Windows needs a slash to identify a driver root
    if (copy.size() != 0 && copy.back() == ':')
        copy += DIR_SEP_CHR;

    int result = _wstat64(Common::UTF8ToUTF16W(copy).c_str(), &file_info);
#else
    int result = stat(copy.c_str(), &file_info);
#endif

    return (result == 0);
}

// Returns true if filename is a directory
bool IsDirectory(const std::string& filename) {
    struct stat file_info;

    std::string copy(filename);
    StripTailDirSlashes(copy);

#ifdef _WIN32
    // Windows needs a slash to identify a driver root
    if (copy.size() != 0 && copy.back() == ':')
        copy += DIR_SEP_CHR;

    int result = _wstat64(Common::UTF8ToUTF16W(copy).c_str(), &file_info);
#else
    int result = stat(copy.c_str(), &file_info);
#endif

    if (result < 0) {
        LOG_DEBUG(Common_Filesystem, "stat failed on {}: {}", filename, GetLastErrorMsg());
        return false;
    }

    return S_ISDIR(file_info.st_mode);
}

// Deletes a given filename, return true on success
// Doesn't supports deleting a directory
bool Delete(const std::string& filename) {
    LOG_TRACE(Common_Filesystem, "file {}", filename);

    // Return true because we care about the file no
    // being there, not the actual delete.
    if (!Exists(filename)) {
        LOG_DEBUG(Common_Filesystem, "{} does not exist", filename);
        return true;
    }

    // We can't delete a directory
    if (IsDirectory(filename)) {
        LOG_ERROR(Common_Filesystem, "Failed: {} is a directory", filename);
        return false;
    }

#ifdef _WIN32
    if (!DeleteFileW(Common::UTF8ToUTF16W(filename).c_str())) {
        LOG_ERROR(Common_Filesystem, "DeleteFile failed on {}: {}", filename, GetLastErrorMsg());
        return false;
    }
#else
    if (unlink(filename.c_str()) == -1) {
        LOG_ERROR(Common_Filesystem, "unlink failed on {}: {}", filename, GetLastErrorMsg());
        return false;
    }
#endif

    return true;
}

// Returns true if successful, or path already exists.
bool CreateDir(const std::string& path) {
    LOG_TRACE(Common_Filesystem, "directory {}", path);
#ifdef _WIN32
    if (::CreateDirectoryW(Common::UTF8ToUTF16W(path).c_str(), nullptr))
        return true;
    DWORD error = GetLastError();
    if (error == ERROR_ALREADY_EXISTS) {
        LOG_DEBUG(Common_Filesystem, "CreateDirectory failed on {}: already exists", path);
        return true;
    }
    LOG_ERROR(Common_Filesystem, "CreateDirectory failed on {}: {}", path, error);
    return false;
#else
    if (mkdir(path.c_str(), 0755) == 0)
        return true;

    int err = errno;

    if (err == EEXIST) {
        LOG_DEBUG(Common_Filesystem, "mkdir failed on {}: already exists", path);
        return true;
    }

    LOG_ERROR(Common_Filesystem, "mkdir failed on {}: {}", path, strerror(err));
    return false;
#endif
}

// Creates the full path of fullPath returns true on success
bool CreateFullPath(const std::string& fullPath) {
    int panicCounter = 100;
    LOG_TRACE(Common_Filesystem, "path {}", fullPath);

    if (FileUtil::Exists(fullPath)) {
        LOG_DEBUG(Common_Filesystem, "path exists {}", fullPath);
        return true;
    }

    std::size_t position = 0;
    while (true) {
        // Find next sub path
        position = fullPath.find(DIR_SEP_CHR, position);

        // we're done, yay!
        if (position == fullPath.npos)
            return true;

        // Include the '/' so the first call is CreateDir("/") rather than CreateDir("")
        std::string const subPath(fullPath.substr(0, position + 1));
        if (!FileUtil::IsDirectory(subPath) && !FileUtil::CreateDir(subPath)) {
            LOG_ERROR(Common, "CreateFullPath: directory creation failed");
            return false;
        }

        // A safety check
        panicCounter--;
        if (panicCounter <= 0) {
            LOG_ERROR(Common, "CreateFullPath: directory structure is too deep");
            return false;
        }
        position++;
    }
}

// Deletes a directory filename, returns true on success
bool DeleteDir(const std::string& filename) {
    LOG_TRACE(Common_Filesystem, "directory {}", filename);

    // check if a directory
    if (!FileUtil::IsDirectory(filename)) {
        LOG_ERROR(Common_Filesystem, "Not a directory {}", filename);
        return false;
    }

#ifdef _WIN32
    if (::RemoveDirectoryW(Common::UTF8ToUTF16W(filename).c_str()))
        return true;
#else
    if (rmdir(filename.c_str()) == 0)
        return true;
#endif
    LOG_ERROR(Common_Filesystem, "failed {}: {}", filename, GetLastErrorMsg());

    return false;
}

// renames file srcFilename to destFilename, returns true on success
bool Rename(const std::string& srcFilename, const std::string& destFilename) {
    LOG_TRACE(Common_Filesystem, "{} --> {}", srcFilename, destFilename);
#ifdef _WIN32
    if (_wrename(Common::UTF8ToUTF16W(srcFilename).c_str(),
                 Common::UTF8ToUTF16W(destFilename).c_str()) == 0)
        return true;
#else
    if (rename(srcFilename.c_str(), destFilename.c_str()) == 0)
        return true;
#endif
    LOG_ERROR(Common_Filesystem, "failed {} --> {}: {}", srcFilename, destFilename,
              GetLastErrorMsg());
    return false;
}

// copies file srcFilename to destFilename, returns true on success
bool Copy(const std::string& srcFilename, const std::string& destFilename) {
    LOG_TRACE(Common_Filesystem, "{} --> {}", srcFilename, destFilename);
#ifdef _WIN32
    if (CopyFileW(Common::UTF8ToUTF16W(srcFilename).c_str(),
                  Common::UTF8ToUTF16W(destFilename).c_str(), FALSE))
        return true;

    LOG_ERROR(Common_Filesystem, "failed {} --> {}: {}", srcFilename, destFilename,
              GetLastErrorMsg());
    return false;
#else
    using CFilePointer = std::unique_ptr<FILE, decltype(&std::fclose)>;

    // Open input file
    CFilePointer input{fopen(srcFilename.c_str(), "rb"), std::fclose};
    if (!input) {
        LOG_ERROR(Common_Filesystem, "opening input failed {} --> {}: {}", srcFilename,
                  destFilename, GetLastErrorMsg());
        return false;
    }

    // open output file
    CFilePointer output{fopen(destFilename.c_str(), "wb"), std::fclose};
    if (!output) {
        LOG_ERROR(Common_Filesystem, "opening output failed {} --> {}: {}", srcFilename,
                  destFilename, GetLastErrorMsg());
        return false;
    }

    // copy loop
    std::array<char, 1024> buffer;
    while (!feof(input.get())) {
        // read input
        std::size_t rnum = fread(buffer.data(), sizeof(char), buffer.size(), input.get());
        if (rnum != buffer.size()) {
            if (ferror(input.get()) != 0) {
                LOG_ERROR(Common_Filesystem, "failed reading from source, {} --> {}: {}",
                          srcFilename, destFilename, GetLastErrorMsg());
                return false;
            }
        }

        // write output
        std::size_t wnum = fwrite(buffer.data(), sizeof(char), rnum, output.get());
        if (wnum != rnum) {
            LOG_ERROR(Common_Filesystem, "failed writing to output, {} --> {}: {}", srcFilename,
                      destFilename, GetLastErrorMsg());
            return false;
        }
    }

    return true;
#endif
}

// Returns the size of filename (64bit)
u64 GetSize(const std::string& filename) {
    if (!Exists(filename)) {
        LOG_ERROR(Common_Filesystem, "failed {}: No such file", filename);
        return 0;
    }

    if (IsDirectory(filename)) {
        LOG_ERROR(Common_Filesystem, "failed {}: is a directory", filename);
        return 0;
    }

    struct stat buf;
#ifdef _WIN32
    if (_wstat64(Common::UTF8ToUTF16W(filename).c_str(), &buf) == 0)
#else
    if (stat(filename.c_str(), &buf) == 0)
#endif
    {
        LOG_TRACE(Common_Filesystem, "{}: {}", filename, buf.st_size);
        return buf.st_size;
    }

    LOG_ERROR(Common_Filesystem, "Stat failed {}: {}", filename, GetLastErrorMsg());
    return 0;
}

// Overloaded GetSize, accepts file descriptor
u64 GetSize(const int fd) {
    struct stat buf;
    if (fstat(fd, &buf) != 0) {
        LOG_ERROR(Common_Filesystem, "GetSize: stat failed {}: {}", fd, GetLastErrorMsg());
        return 0;
    }
    return buf.st_size;
}

// Overloaded GetSize, accepts FILE*
u64 GetSize(FILE* f) {
    // can't use off_t here because it can be 32-bit
    u64 pos = ftello(f);
    if (fseeko(f, 0, SEEK_END) != 0) {
        LOG_ERROR(Common_Filesystem, "GetSize: seek failed {}: {}", fmt::ptr(f), GetLastErrorMsg());
        return 0;
    }
    u64 size = ftello(f);
    if ((size != pos) && (fseeko(f, pos, SEEK_SET) != 0)) {
        LOG_ERROR(Common_Filesystem, "GetSize: seek failed {}: {}", fmt::ptr(f), GetLastErrorMsg());
        return 0;
    }
    return size;
}

// creates an empty file filename, returns true on success
bool CreateEmptyFile(const std::string& filename) {
    LOG_TRACE(Common_Filesystem, "{}", filename);

    if (!FileUtil::IOFile(filename, "wb").IsOpen()) {
        LOG_ERROR(Common_Filesystem, "failed {}: {}", filename, GetLastErrorMsg());
        return false;
    }

    return true;
}

bool ForeachDirectoryEntry(u64* num_entries_out, const std::string& directory,
                           DirectoryEntryCallable callback) {
    LOG_TRACE(Common_Filesystem, "directory {}", directory);

    // How many files + directories we found
    u64 found_entries = 0;

    // Save the status of callback function
    bool callback_error = false;

#ifdef _WIN32
    // Find the first file in the directory.
    WIN32_FIND_DATAW ffd;

    HANDLE handle_find = FindFirstFileW(Common::UTF8ToUTF16W(directory + "\\*").c_str(), &ffd);
    if (handle_find == INVALID_HANDLE_VALUE) {
        FindClose(handle_find);
        return false;
    }
    // windows loop
    do {
        const std::string virtual_name(Common::UTF16ToUTF8(ffd.cFileName));
#else
    DIR* dirp = opendir(directory.c_str());
    if (!dirp)
        return false;

    // non windows loop
    while (struct dirent* result = readdir(dirp)) {
        const std::string virtual_name(result->d_name);
#endif

        if (virtual_name == "." || virtual_name == "..")
            continue;

        u64 ret_entries = 0;
        if (!callback(&ret_entries, directory, virtual_name)) {
            callback_error = true;
            break;
        }
        found_entries += ret_entries;

#ifdef _WIN32
    } while (FindNextFileW(handle_find, &ffd) != 0);
    FindClose(handle_find);
#else
    }
    closedir(dirp);
#endif

    if (callback_error)
        return false;

    // num_entries_out is allowed to be specified nullptr, in which case we shouldn't try to set it
    if (num_entries_out != nullptr)
        *num_entries_out = found_entries;
    return true;
}

u64 ScanDirectoryTree(const std::string& directory, FSTEntry& parent_entry,
                      unsigned int recursion) {
    const auto callback = [recursion, &parent_entry](u64* num_entries_out,
                                                     const std::string& directory,
                                                     const std::string& virtual_name) -> bool {
        FSTEntry entry;
        entry.virtualName = virtual_name;
        entry.physicalName = directory + DIR_SEP + virtual_name;

        if (IsDirectory(entry.physicalName)) {
            entry.isDirectory = true;
            // is a directory, lets go inside if we didn't recurse to often
            if (recursion > 0) {
                entry.size = ScanDirectoryTree(entry.physicalName, entry, recursion - 1);
                *num_entries_out += entry.size;
            } else {
                entry.size = 0;
            }
        } else { // is a file
            entry.isDirectory = false;
            entry.size = GetSize(entry.physicalName);
        }
        (*num_entries_out)++;

        // Push into the tree
        parent_entry.children.push_back(std::move(entry));
        return true;
    };

    u64 num_entries;
    return ForeachDirectoryEntry(&num_entries, directory, callback) ? num_entries : 0;
}

bool DeleteDirRecursively(const std::string& directory, unsigned int recursion) {
    const auto callback = [recursion](u64* num_entries_out, const std::string& directory,
                                      const std::string& virtual_name) -> bool {
        std::string new_path = directory + DIR_SEP_CHR + virtual_name;

        if (IsDirectory(new_path)) {
            if (recursion == 0)
                return false;
            return DeleteDirRecursively(new_path, recursion - 1);
        }
        return Delete(new_path);
    };

    if (!ForeachDirectoryEntry(nullptr, directory, callback))
        return false;

    // Delete the outermost directory
    FileUtil::DeleteDir(directory);
    return true;
}

// Create directory and copy contents (does not overwrite existing files)
void CopyDir(const std::string& source_path, const std::string& dest_path) {
#ifndef _WIN32
    if (source_path == dest_path)
        return;
    if (!FileUtil::Exists(source_path))
        return;
    if (!FileUtil::Exists(dest_path))
        FileUtil::CreateFullPath(dest_path);

    DIR* dirp = opendir(source_path.c_str());
    if (!dirp)
        return;

    while (struct dirent* result = readdir(dirp)) {
        const std::string virtualName(result->d_name);
        // check for "." and ".."
        if (((virtualName[0] == '.') && (virtualName[1] == '\0')) ||
            ((virtualName[0] == '.') && (virtualName[1] == '.') && (virtualName[2] == '\0')))
            continue;

        std::string source, dest;
        source = source_path + virtualName;
        dest = dest_path + virtualName;
        if (IsDirectory(source)) {
            source += '/';
            dest += '/';
            if (!FileUtil::Exists(dest))
                FileUtil::CreateFullPath(dest);
            CopyDir(source, dest);
        } else if (!FileUtil::Exists(dest))
            FileUtil::Copy(source, dest);
    }
    closedir(dirp);
#endif
}

// Returns the current directory
std::string GetCurrentDir() {
// Get the current working directory (getcwd uses malloc)
#ifdef _WIN32
    wchar_t* dir;
    if (!(dir = _wgetcwd(nullptr, 0))) {
#else
    char* dir;
    if (!(dir = getcwd(nullptr, 0))) {
#endif
        LOG_ERROR(Common_Filesystem, "GetCurrentDirectory failed: {}", GetLastErrorMsg());
        return nullptr;
    }
#ifdef _WIN32
    std::string strDir = Common::UTF16ToUTF8(dir);
#else
    std::string strDir = dir;
#endif
    free(dir);
    return strDir;
}

// Sets the current directory to the given directory
bool SetCurrentDir(const std::string& directory) {
#ifdef _WIN32
    return _wchdir(Common::UTF8ToUTF16W(directory).c_str()) == 0;
#else
    return chdir(directory.c_str()) == 0;
#endif
}

#if defined(__APPLE__)
std::string GetBundleDirectory() {
    CFURLRef BundleRef;
    char AppBundlePath[MAXPATHLEN];
    // Get the main bundle for the app
    BundleRef = CFBundleCopyBundleURL(CFBundleGetMainBundle());
    CFStringRef BundlePath = CFURLCopyFileSystemPath(BundleRef, kCFURLPOSIXPathStyle);
    CFStringGetFileSystemRepresentation(BundlePath, AppBundlePath, sizeof(AppBundlePath));
    CFRelease(BundleRef);
    CFRelease(BundlePath);

    return AppBundlePath;
}
#endif

#ifdef _WIN32
const std::string& GetExeDirectory() {
    static std::string exe_path;
    if (exe_path.empty()) {
        wchar_t wchar_exe_path[2048];
        GetModuleFileNameW(nullptr, wchar_exe_path, 2048);
        exe_path = Common::UTF16ToUTF8(wchar_exe_path);
        exe_path = exe_path.substr(0, exe_path.find_last_of('\\'));
    }
    return exe_path;
}

std::string AppDataRoamingDirectory() {
    PWSTR pw_local_path = nullptr;
    // Only supported by Windows Vista or later
    SHGetKnownFolderPath(FOLDERID_RoamingAppData, 0, nullptr, &pw_local_path);
    std::string local_path = Common::UTF16ToUTF8(pw_local_path);
    CoTaskMemFree(pw_local_path);
    return local_path;
}
#else
/**
 * @return The user’s home directory on POSIX systems
 */
static const std::string& GetHomeDirectory() {
    static std::string home_path;
    if (home_path.empty()) {
        const char* envvar = getenv("HOME");
        if (envvar) {
            home_path = envvar;
        } else {
            auto pw = getpwuid(getuid());
            ASSERT_MSG(pw,
                       "$HOME isn’t defined, and the current user can’t be found in /etc/passwd.");
            home_path = pw->pw_dir;
        }
    }
    return home_path;
}

/**
 * Follows the XDG Base Directory Specification to get a directory path
 * @param envvar The XDG environment variable to get the value from
 * @return The directory path
 * @sa http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
 */
static const std::string GetUserDirectory(const std::string& envvar) {
    const char* directory = getenv(envvar.c_str());

    std::string user_dir;
    if (directory) {
        user_dir = directory;
    } else {
        std::string subdirectory;
        if (envvar == "XDG_DATA_HOME")
            subdirectory = DIR_SEP ".local" DIR_SEP "share";
        else if (envvar == "XDG_CONFIG_HOME")
            subdirectory = DIR_SEP ".config";
        else if (envvar == "XDG_CACHE_HOME")
            subdirectory = DIR_SEP ".cache";
        else
            ASSERT_MSG(false, "Unknown XDG variable {}.", envvar);
        user_dir = GetHomeDirectory() + subdirectory;
    }

    ASSERT_MSG(!user_dir.empty(), "User directory {} mustn’t be empty.", envvar);
    ASSERT_MSG(user_dir[0] == '/', "User directory {} must be absolute.", envvar);

    return user_dir;
}
#endif

std::string GetSysDirectory() {
    std::string sysDir;

#if defined(__APPLE__)
    sysDir = GetBundleDirectory();
    sysDir += DIR_SEP;
    sysDir += SYSDATA_DIR;
#else
    sysDir = SYSDATA_DIR;
#endif
    sysDir += DIR_SEP;

    LOG_DEBUG(Common_Filesystem, "Setting to {}:", sysDir);
    return sysDir;
}

// Returns a string with a yuzu data dir or file in the user's home
// directory. To be used in "multi-user" mode (that is, installed).
const std::string& GetUserPath(UserPath path, const std::string& new_path) {
    static std::unordered_map<UserPath, std::string> paths;
    auto& user_path = paths[UserPath::UserDir];

    // Set up all paths and files on the first run
    if (user_path.empty()) {
#ifdef _WIN32
        user_path = GetExeDirectory() + DIR_SEP USERDATA_DIR DIR_SEP;
        if (!FileUtil::IsDirectory(user_path)) {
            user_path = AppDataRoamingDirectory() + DIR_SEP EMU_DATA_DIR DIR_SEP;
        } else {
            LOG_INFO(Common_Filesystem, "Using the local user directory");
        }

        paths.emplace(UserPath::ConfigDir, user_path + CONFIG_DIR DIR_SEP);
        paths.emplace(UserPath::CacheDir, user_path + CACHE_DIR DIR_SEP);
#else
        if (FileUtil::Exists(ROOT_DIR DIR_SEP USERDATA_DIR)) {
            user_path = ROOT_DIR DIR_SEP USERDATA_DIR DIR_SEP;
            paths.emplace(UserPath::ConfigDir, user_path + CONFIG_DIR DIR_SEP);
            paths.emplace(UserPath::CacheDir, user_path + CACHE_DIR DIR_SEP);
        } else {
            std::string data_dir = GetUserDirectory("XDG_DATA_HOME");
            std::string config_dir = GetUserDirectory("XDG_CONFIG_HOME");
            std::string cache_dir = GetUserDirectory("XDG_CACHE_HOME");

            user_path = data_dir + DIR_SEP EMU_DATA_DIR DIR_SEP;
            paths.emplace(UserPath::ConfigDir, config_dir + DIR_SEP EMU_DATA_DIR DIR_SEP);
            paths.emplace(UserPath::CacheDir, cache_dir + DIR_SEP EMU_DATA_DIR DIR_SEP);
        }
#endif
        paths.emplace(UserPath::SDMCDir, user_path + SDMC_DIR DIR_SEP);
        paths.emplace(UserPath::NANDDir, user_path + NAND_DIR DIR_SEP);
        paths.emplace(UserPath::LoadDir, user_path + LOAD_DIR DIR_SEP);
        paths.emplace(UserPath::DumpDir, user_path + DUMP_DIR DIR_SEP);
        paths.emplace(UserPath::SysDataDir, user_path + SYSDATA_DIR DIR_SEP);
        paths.emplace(UserPath::KeysDir, user_path + KEYS_DIR DIR_SEP);
        // TODO: Put the logs in a better location for each OS
        paths.emplace(UserPath::LogDir, user_path + LOG_DIR DIR_SEP);
    }

    if (!new_path.empty()) {
        if (!FileUtil::IsDirectory(new_path)) {
            LOG_ERROR(Common_Filesystem, "Invalid path specified {}", new_path);
            return paths[path];
        } else {
            paths[path] = new_path;
        }

        switch (path) {
        case UserPath::RootDir:
            user_path = paths[UserPath::RootDir] + DIR_SEP;
            break;

        case UserPath::UserDir:
            user_path = paths[UserPath::RootDir] + DIR_SEP;
            paths[UserPath::ConfigDir] = user_path + CONFIG_DIR DIR_SEP;
            paths[UserPath::CacheDir] = user_path + CACHE_DIR DIR_SEP;
            paths[UserPath::SDMCDir] = user_path + SDMC_DIR DIR_SEP;
            paths[UserPath::NANDDir] = user_path + NAND_DIR DIR_SEP;
            break;
        }
    }

    return paths[path];
}

std::string GetHactoolConfigurationPath() {
#ifdef _WIN32
    PWSTR pw_local_path = nullptr;
    if (SHGetKnownFolderPath(FOLDERID_Profile, 0, nullptr, &pw_local_path) != S_OK)
        return "";
    std::string local_path = Common::UTF16ToUTF8(pw_local_path);
    CoTaskMemFree(pw_local_path);
    return local_path + "\\.switch";
#else
    return GetHomeDirectory() + "/.switch";
#endif
}

std::string GetNANDRegistrationDir(bool system) {
    if (system)
        return GetUserPath(UserPath::NANDDir) + "system/Contents/registered/";
    return GetUserPath(UserPath::NANDDir) + "user/Contents/registered/";
}

std::size_t WriteStringToFile(bool text_file, const std::string& str, const char* filename) {
    return FileUtil::IOFile(filename, text_file ? "w" : "wb").WriteBytes(str.data(), str.size());
}

std::size_t ReadFileToString(bool text_file, const char* filename, std::string& str) {
    IOFile file(filename, text_file ? "r" : "rb");

    if (!file.IsOpen())
        return 0;

    str.resize(static_cast<u32>(file.GetSize()));
    return file.ReadArray(&str[0], str.size());
}

/**
 * Splits the filename into 8.3 format
 * Loosely implemented following https://en.wikipedia.org/wiki/8.3_filename
 * @param filename The normal filename to use
 * @param short_name A 9-char array in which the short name will be written
 * @param extension A 4-char array in which the extension will be written
 */
void SplitFilename83(const std::string& filename, std::array<char, 9>& short_name,
                     std::array<char, 4>& extension) {
    const std::string forbidden_characters = ".\"/\\[]:;=, ";

    // On a FAT32 partition, 8.3 names are stored as a 11 bytes array, filled with spaces.
    short_name = {{' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', '\0'}};
    extension = {{' ', ' ', ' ', '\0'}};

    std::string::size_type point = filename.rfind('.');
    if (point == filename.size() - 1)
        point = filename.rfind('.', point);

    // Get short name.
    int j = 0;
    for (char letter : filename.substr(0, point)) {
        if (forbidden_characters.find(letter, 0) != std::string::npos)
            continue;
        if (j == 8) {
            // TODO(Link Mauve): also do that for filenames containing a space.
            // TODO(Link Mauve): handle multiple files having the same short name.
            short_name[6] = '~';
            short_name[7] = '1';
            break;
        }
        short_name[j++] = toupper(letter);
    }

    // Get extension.
    if (point != std::string::npos) {
        j = 0;
        for (char letter : filename.substr(point + 1, 3))
            extension[j++] = toupper(letter);
    }
}

std::vector<std::string> SplitPathComponents(std::string_view filename) {
    std::string copy(filename);
    std::replace(copy.begin(), copy.end(), '\\', '/');
    std::vector<std::string> out;

    std::stringstream stream(copy);
    std::string item;
    while (std::getline(stream, item, '/')) {
        out.push_back(std::move(item));
    }

    return out;
}

std::string_view GetParentPath(std::string_view path) {
    const auto name_bck_index = path.rfind('\\');
    const auto name_fwd_index = path.rfind('/');
    std::size_t name_index;

    if (name_bck_index == std::string_view::npos || name_fwd_index == std::string_view::npos) {
        name_index = std::min(name_bck_index, name_fwd_index);
    } else {
        name_index = std::max(name_bck_index, name_fwd_index);
    }

    return path.substr(0, name_index);
}

std::string_view GetPathWithoutTop(std::string_view path) {
    if (path.empty()) {
        return path;
    }

    while (path[0] == '\\' || path[0] == '/') {
        path.remove_prefix(1);
        if (path.empty()) {
            return path;
        }
    }

    const auto name_bck_index = path.find('\\');
    const auto name_fwd_index = path.find('/');
    return path.substr(std::min(name_bck_index, name_fwd_index) + 1);
}

std::string_view GetFilename(std::string_view path) {
    const auto name_index = path.find_last_of("\\/");

    if (name_index == std::string_view::npos) {
        return {};
    }

    return path.substr(name_index + 1);
}

std::string_view GetExtensionFromFilename(std::string_view name) {
    const std::size_t index = name.rfind('.');

    if (index == std::string_view::npos) {
        return {};
    }

    return name.substr(index + 1);
}

std::string_view RemoveTrailingSlash(std::string_view path) {
    if (path.empty()) {
        return path;
    }

    if (path.back() == '\\' || path.back() == '/') {
        path.remove_suffix(1);
        return path;
    }

    return path;
}

std::string SanitizePath(std::string_view path_, DirectorySeparator directory_separator) {
    std::string path(path_);
    char type1 = directory_separator == DirectorySeparator::BackwardSlash ? '/' : '\\';
    char type2 = directory_separator == DirectorySeparator::BackwardSlash ? '\\' : '/';

    if (directory_separator == DirectorySeparator::PlatformDefault) {
#ifdef _WIN32
        type1 = '/';
        type2 = '\\';
#endif
    }

    std::replace(path.begin(), path.end(), type1, type2);
    path.erase(std::unique(path.begin(), path.end(),
                           [type2](char c1, char c2) { return c1 == type2 && c2 == type2; }),
               path.end());
    return std::string(RemoveTrailingSlash(path));
}

IOFile::IOFile() {}

IOFile::IOFile(const std::string& filename, const char openmode[], int flags) {
    Open(filename, openmode, flags);
}

IOFile::~IOFile() {
    Close();
}

IOFile::IOFile(IOFile&& other) noexcept {
    Swap(other);
}

IOFile& IOFile::operator=(IOFile&& other) noexcept {
    Swap(other);
    return *this;
}

void IOFile::Swap(IOFile& other) noexcept {
    std::swap(m_file, other.m_file);
}

bool IOFile::Open(const std::string& filename, const char openmode[], int flags) {
    Close();
#ifdef _WIN32
    if (flags != 0) {
        m_file = _wfsopen(Common::UTF8ToUTF16W(filename).c_str(),
                          Common::UTF8ToUTF16W(openmode).c_str(), flags);
    } else {
        _wfopen_s(&m_file, Common::UTF8ToUTF16W(filename).c_str(),
                  Common::UTF8ToUTF16W(openmode).c_str());
    }
#else
    m_file = fopen(filename.c_str(), openmode);
#endif

    return IsOpen();
}

bool IOFile::Close() {
    if (!IsOpen() || 0 != std::fclose(m_file))
        return false;

    m_file = nullptr;
    return true;
}

u64 IOFile::GetSize() const {
    if (IsOpen())
        return FileUtil::GetSize(m_file);

    return 0;
}

bool IOFile::Seek(s64 off, int origin) const {
    return IsOpen() && 0 == fseeko(m_file, off, origin);
}

u64 IOFile::Tell() const {
    if (IsOpen())
        return ftello(m_file);

    return -1;
}

bool IOFile::Flush() {
    return IsOpen() && 0 == std::fflush(m_file);
}

bool IOFile::Resize(u64 size) {
    return IsOpen() && 0 ==
#ifdef _WIN32
                           // ector: _chsize sucks, not 64-bit safe
                           // F|RES: changed to _chsize_s. i think it is 64-bit safe
                           _chsize_s(_fileno(m_file), size)
#else
                           // TODO: handle 64bit and growing
                           ftruncate(fileno(m_file), size)
#endif
        ;
}

} // namespace FileUtil