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3 ** Copyright (C) 2014 Ivan Komissarov <ABBAPOH@gmail.com>
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40 
41 #include "qstorageinfo_p.h"
42 
43 #include <QtCore/qdiriterator.h>
44 #include <QtCore/qfileinfo.h>
45 #include <QtCore/qtextstream.h>
46 
47 #include <QtCore/private/qcore_unix_p.h>
48 #include <QtCore/private/qlocale_tools_p.h>
49 
50 #include <errno.h>
51 #include <sys/stat.h>
52 
53 #if defined(Q_OS_BSD4)
54 #  include <sys/mount.h>
55 #  include <sys/statvfs.h>
56 #elif defined(Q_OS_ANDROID)
57 #  include <sys/mount.h>
58 #  include <sys/vfs.h>
59 #  include <mntent.h>
60 #elif defined(Q_OS_LINUX) || defined(Q_OS_HURD)
61 #  include <mntent.h>
62 #  include <sys/statvfs.h>
63 #  include <sys/sysmacros.h>
64 #elif defined(Q_OS_SOLARIS)
65 #  include <sys/mnttab.h>
66 #  include <sys/statvfs.h>
67 #elif defined(Q_OS_HAIKU)
68 #  include <Directory.h>
69 #  include <Path.h>
70 #  include <Volume.h>
71 #  include <VolumeRoster.h>
72 #  include <fs_info.h>
73 #  include <sys/statvfs.h>
74 #else
75 #  include <sys/statvfs.h>
76 #endif
77 
78 #if defined(Q_OS_BSD4)
79 #  if defined(Q_OS_NETBSD)
80 #    define QT_STATFSBUF struct statvfs
81 #    define QT_STATFS    ::statvfs
82 #  else
83 #    define QT_STATFSBUF struct statfs
84 #    define QT_STATFS    ::statfs
85 #  endif
86 
87 #  if !defined(ST_RDONLY)
88 #    define ST_RDONLY MNT_RDONLY
89 #  endif
90 #  if !defined(_STATFS_F_FLAGS) && !defined(Q_OS_NETBSD)
91 #    define _STATFS_F_FLAGS 1
92 #  endif
93 #elif defined(Q_OS_ANDROID)
94 #  define QT_STATFS    ::statfs
95 #  define QT_STATFSBUF struct statfs
96 #  if !defined(ST_RDONLY)
97 #    define ST_RDONLY 1 // hack for missing define on Android
98 #  endif
99 #elif defined(Q_OS_HAIKU)
100 #  define QT_STATFSBUF struct statvfs
101 #  define QT_STATFS    ::statvfs
102 #else
103 #  if defined(QT_LARGEFILE_SUPPORT)
104 #    define QT_STATFSBUF struct statvfs64
105 #    define QT_STATFS    ::statvfs64
106 #  else
107 #    define QT_STATFSBUF struct statvfs
108 #    define QT_STATFS    ::statvfs
109 #  endif // QT_LARGEFILE_SUPPORT
110 #endif // Q_OS_BSD4
111 
112 #if __has_include(<paths.h>)
113 #  include <paths.h>
114 #endif
115 #ifndef _PATH_MOUNTED
116 #  define _PATH_MOUNTED     "/etc/mnttab"
117 #endif
118 
119 QT_BEGIN_NAMESPACE
120 
121 class QStorageIterator
122 {
123 public:
124     QStorageIterator();
125     ~QStorageIterator();
126 
127     inline bool isValid() const;
128     inline bool next();
129     inline QString rootPath() const;
130     inline QByteArray fileSystemType() const;
131     inline QByteArray device() const;
132     inline QByteArray options() const;
133     inline QByteArray subvolume() const;
134 private:
135 #if defined(Q_OS_BSD4)
136     QT_STATFSBUF *stat_buf;
137     int entryCount;
138     int currentIndex;
139 #elif defined(Q_OS_SOLARIS)
140     FILE *fp;
141     mnttab mnt;
142 #elif defined(Q_OS_ANDROID)
143     QFile file;
144     QByteArray m_rootPath;
145     QByteArray m_fileSystemType;
146     QByteArray m_device;
147     QByteArray m_options;
148 #elif defined(Q_OS_LINUX) || defined(Q_OS_HURD)
149     struct mountinfoent : public mntent {
150         // Details from proc(5) section from /proc/<pid>/mountinfo:
151         //(1)  mount ID: a unique ID for the mount (may be reused after umount(2)).
152         int mount_id;
153         //(2)  parent ID: the ID of the parent mount (or of self for the top of the mount tree).
154 //      int parent_id;
155         //(3)  major:minor: the value of st_dev for files on this filesystem (see stat(2)).
156         dev_t rdev;
157         //(4)  root: the pathname of the directory in the filesystem which forms the root of this mount.
158         char *subvolume;
159         //(5)  mount point: the pathname of the mount point relative to the process's root directory.
160 //      char *mnt_dir;      // in mntent
161         //(6)  mount options: per-mount options.
162 //      char *mnt_opts;     // in mntent
163         //(7)  optional fields: zero or more fields of the form "tag[:value]"; see below.
164 //      int flags;
165         //(8)  separator: the end of the optional fields is marked by a single hyphen.
166 
167         //(9)  filesystem type: the filesystem type in the form "type[.subtype]".
168 //      char *mnt_type;     // in mntent
169         //(10) mount source: filesystem-specific information or "none".
170 //      char *mnt_fsname;   // in mntent
171         //(11) super options: per-superblock options.
172         char *superopts;
173     };
174 
175     FILE *fp;
176     QByteArray buffer;
177     mountinfoent mnt;
178     bool usingMountinfo;
179 #elif defined(Q_OS_HAIKU)
180     BVolumeRoster m_volumeRoster;
181 
182     QByteArray m_rootPath;
183     QByteArray m_fileSystemType;
184     QByteArray m_device;
185 #endif
186 };
187 
188 template <typename String>
isParentOf(const String & parent,const QString & dirName)189 static bool isParentOf(const String &parent, const QString &dirName)
190 {
191     return dirName.startsWith(parent) &&
192             (dirName.size() == parent.size() || dirName.at(parent.size()) == QLatin1Char('/') ||
193              parent.size() == 1);
194 }
195 
shouldIncludeFs(const QStorageIterator & it)196 static bool shouldIncludeFs(const QStorageIterator &it)
197 {
198     /*
199      * This function implements a heuristic algorithm to determine whether a
200      * given mount should be reported to the user. Our objective is to list
201      * only entries that the end-user would find useful.
202      *
203      * We therefore ignore:
204      *  - mounted in /dev, /proc, /sys: special mounts
205      *    (this will catch /sys/fs/cgroup, /proc/sys/fs/binfmt_misc, /dev/pts,
206      *    some of which are tmpfs on Linux)
207      *  - mounted in /var/run or /var/lock: most likely pseudofs
208      *    (on earlier systemd versions, /var/run was a bind-mount of /run, so
209      *    everything would be unnecessarily duplicated)
210      *  - filesystem type is "rootfs": artifact of the root-pivot on some Linux
211      *    initrd
212      *  - if the filesystem total size is zero, it's a pseudo-fs (not checked here).
213      */
214 
215     QString mountDir = it.rootPath();
216     if (isParentOf(QLatin1String("/dev"), mountDir)
217         || isParentOf(QLatin1String("/proc"), mountDir)
218         || isParentOf(QLatin1String("/sys"), mountDir)
219         || isParentOf(QLatin1String("/var/run"), mountDir)
220         || isParentOf(QLatin1String("/var/lock"), mountDir)) {
221         return false;
222     }
223 
224 #if defined(Q_OS_LINUX) && !defined(Q_OS_ANDROID)
225     if (it.fileSystemType() == "rootfs")
226         return false;
227 #endif
228 
229     // size checking in mountedVolumes()
230     return true;
231 }
232 
233 #if defined(Q_OS_BSD4)
234 
235 #ifndef MNT_NOWAIT
236 #  define MNT_NOWAIT 0
237 #endif
238 
QStorageIterator()239 inline QStorageIterator::QStorageIterator()
240     : entryCount(::getmntinfo(&stat_buf, MNT_NOWAIT)),
241       currentIndex(-1)
242 {
243 }
244 
~QStorageIterator()245 inline QStorageIterator::~QStorageIterator()
246 {
247 }
248 
isValid() const249 inline bool QStorageIterator::isValid() const
250 {
251     return entryCount != -1;
252 }
253 
next()254 inline bool QStorageIterator::next()
255 {
256     return ++currentIndex < entryCount;
257 }
258 
rootPath() const259 inline QString QStorageIterator::rootPath() const
260 {
261     return QFile::decodeName(stat_buf[currentIndex].f_mntonname);
262 }
263 
fileSystemType() const264 inline QByteArray QStorageIterator::fileSystemType() const
265 {
266     return QByteArray(stat_buf[currentIndex].f_fstypename);
267 }
268 
device() const269 inline QByteArray QStorageIterator::device() const
270 {
271     return QByteArray(stat_buf[currentIndex].f_mntfromname);
272 }
273 
options() const274 inline QByteArray QStorageIterator::options() const
275 {
276     return QByteArray();
277 }
278 
subvolume() const279 inline QByteArray QStorageIterator::subvolume() const
280 {
281     return QByteArray();
282 }
283 #elif defined(Q_OS_SOLARIS)
284 
QStorageIterator()285 inline QStorageIterator::QStorageIterator()
286 {
287     const int fd = qt_safe_open(_PATH_MOUNTED, O_RDONLY);
288     fp = ::fdopen(fd, "r");
289 }
290 
~QStorageIterator()291 inline QStorageIterator::~QStorageIterator()
292 {
293     if (fp)
294         ::fclose(fp);
295 }
296 
isValid() const297 inline bool QStorageIterator::isValid() const
298 {
299     return fp != nullptr;
300 }
301 
next()302 inline bool QStorageIterator::next()
303 {
304     return ::getmntent(fp, &mnt) == 0;
305 }
306 
rootPath() const307 inline QString QStorageIterator::rootPath() const
308 {
309     return QFile::decodeName(mnt.mnt_mountp);
310 }
311 
fileSystemType() const312 inline QByteArray QStorageIterator::fileSystemType() const
313 {
314     return QByteArray(mnt.mnt_fstype);
315 }
316 
device() const317 inline QByteArray QStorageIterator::device() const
318 {
319     return QByteArray(mnt.mnt_mntopts);
320 }
321 
subvolume() const322 inline QByteArray QStorageIterator::subvolume() const
323 {
324     return QByteArray();
325 }
326 #elif defined(Q_OS_ANDROID)
327 
QStorageIterator()328 inline QStorageIterator::QStorageIterator()
329 {
330     file.setFileName(_PATH_MOUNTED);
331     file.open(QIODevice::ReadOnly | QIODevice::Text);
332 }
333 
~QStorageIterator()334 inline QStorageIterator::~QStorageIterator()
335 {
336 }
337 
isValid() const338 inline bool QStorageIterator::isValid() const
339 {
340     return file.isOpen();
341 }
342 
next()343 inline bool QStorageIterator::next()
344 {
345     QList<QByteArray> data;
346     // If file is virtual, file.readLine() may succeed even when file.atEnd().
347     do {
348         const QByteArray line = file.readLine();
349         if (line.isEmpty() && file.atEnd())
350             return false;
351         data = line.split(' ');
352     } while (data.count() < 4);
353 
354     m_device = data.at(0);
355     m_rootPath = data.at(1);
356     m_fileSystemType = data.at(2);
357     m_options = data.at(3);
358 
359     return true;
360 }
361 
rootPath() const362 inline QString QStorageIterator::rootPath() const
363 {
364     return QFile::decodeName(m_rootPath);
365 }
366 
fileSystemType() const367 inline QByteArray QStorageIterator::fileSystemType() const
368 {
369     return m_fileSystemType;
370 }
371 
device() const372 inline QByteArray QStorageIterator::device() const
373 {
374     return m_device;
375 }
376 
options() const377 inline QByteArray QStorageIterator::options() const
378 {
379     return m_options;
380 }
381 
subvolume() const382 inline QByteArray QStorageIterator::subvolume() const
383 {
384     return QByteArray();
385 }
386 #elif defined(Q_OS_LINUX) || defined(Q_OS_HURD)
387 
388 static const int bufferSize = 1024; // 2 paths (mount point+device) and metainfo;
389                                     // should be enough
390 
QStorageIterator()391 inline QStorageIterator::QStorageIterator() :
392     buffer(QByteArray(bufferSize, 0))
393 {
394     fp = nullptr;
395 
396 #ifdef Q_OS_LINUX
397     // first, try to open /proc/self/mountinfo, which has more details
398     fp = ::fopen("/proc/self/mountinfo", "re");
399 #endif
400     if (fp) {
401         usingMountinfo = true;
402     } else {
403         usingMountinfo = false;
404         fp = ::setmntent(_PATH_MOUNTED, "r");
405     }
406 }
407 
~QStorageIterator()408 inline QStorageIterator::~QStorageIterator()
409 {
410     if (fp) {
411         if (usingMountinfo)
412             ::fclose(fp);
413         else
414             ::endmntent(fp);
415     }
416 }
417 
isValid() const418 inline bool QStorageIterator::isValid() const
419 {
420     return fp != nullptr;
421 }
422 
next()423 inline bool QStorageIterator::next()
424 {
425     mnt.subvolume = nullptr;
426     mnt.superopts = nullptr;
427     if (!usingMountinfo)
428         return ::getmntent_r(fp, &mnt, buffer.data(), buffer.size()) != nullptr;
429 
430     // Helper function to parse paths that the kernel inserts escape sequences
431     // for. The unescaped string is left at \a src and is properly
432     // NUL-terminated. Returns a pointer to the delimiter that terminated the
433     // path, or nullptr if it failed.
434     auto parseMangledPath = [](char *src) {
435         // The kernel escapes with octal the following characters:
436         //  space ' ', tab '\t', backslask '\\', and newline '\n'
437         char *dst = src;
438         while (*src) {
439             switch (*src) {
440             case ' ':
441                 // Unescaped space: end of the field.
442                 *dst = '\0';
443                 return src;
444 
445             default:
446                 *dst++ = *src++;
447                 break;
448 
449             case '\\':
450                 // It always uses exactly three octal characters.
451                 ++src;
452                 char c = (*src++ - '0') << 6;
453                 c |= (*src++ - '0') << 3;
454                 c |= (*src++ - '0');
455                 *dst++ = c;
456                 break;
457             }
458         }
459 
460         // Found a NUL before the end of the field.
461         src = nullptr;
462         return src;
463     };
464 
465     char *ptr = buffer.data();
466     if (fgets(ptr, buffer.size(), fp) == nullptr)
467         return false;
468 
469     size_t len = strlen(buffer.data());
470     if (len == 0)
471         return false;
472     while (Q_UNLIKELY(ptr[len - 1] != '\n' && !feof(fp))) {
473         // buffer wasn't large enough. Enlarge and try again.
474         // (we're readidng from the kernel, so OOM is unlikely)
475         buffer.resize((buffer.size() + 4096) & ~4095);
476         ptr = buffer.data();
477         if (fgets(ptr + len, buffer.size() - len, fp) == nullptr)
478             return false;
479 
480         len += strlen(ptr + len);
481         Q_ASSERT(len < size_t(buffer.size()));
482     }
483     ptr[len - 1] = '\0';
484 
485     // parse the line
486     bool ok;
487     mnt.mnt_freq = 0;
488     mnt.mnt_passno = 0;
489 
490     mnt.mount_id = qstrtoll(ptr, const_cast<const char **>(&ptr), 10, &ok);
491     if (!ptr || !ok)
492         return false;
493 
494     int parent_id = qstrtoll(ptr, const_cast<const char **>(&ptr), 10, &ok);
495     Q_UNUSED(parent_id);
496     if (!ptr || !ok)
497         return false;
498 
499     int rdevmajor = qstrtoll(ptr, const_cast<const char **>(&ptr), 10, &ok);
500     if (!ptr || !ok)
501         return false;
502     if (*ptr != ':')
503         return false;
504     int rdevminor = qstrtoll(ptr + 1, const_cast<const char **>(&ptr), 10, &ok);
505     if (!ptr || !ok)
506         return false;
507     mnt.rdev = makedev(rdevmajor, rdevminor);
508 
509     if (*ptr != ' ')
510         return false;
511 
512     mnt.subvolume = ++ptr;
513     ptr = parseMangledPath(ptr);
514     if (!ptr)
515         return false;
516 
517     // unset a subvolume of "/" -- it's not a *sub* volume
518     if (mnt.subvolume + 1 == ptr)
519         *mnt.subvolume = '\0';
520 
521     mnt.mnt_dir = ++ptr;
522     ptr = parseMangledPath(ptr);
523     if (!ptr)
524         return false;
525 
526     mnt.mnt_opts = ++ptr;
527     ptr = strchr(ptr, ' ');
528     if (!ptr)
529         return false;
530 
531     // we don't parse the flags, so just find the separator
532     if (char *const dashed = strstr(ptr, " - ")) {
533         *ptr = '\0';
534         ptr = dashed + strlen(" - ") - 1;
535     } else {
536         return false;
537     }
538 
539     mnt.mnt_type = ++ptr;
540     ptr = strchr(ptr, ' ');
541     if (!ptr)
542         return false;
543     *ptr = '\0';
544 
545     mnt.mnt_fsname = ++ptr;
546     ptr = parseMangledPath(ptr);
547     if (!ptr)
548         return false;
549 
550     mnt.superopts = ++ptr;
551     ptr += strcspn(ptr, " \n");
552     *ptr = '\0';
553 
554     return true;
555 }
556 
rootPath() const557 inline QString QStorageIterator::rootPath() const
558 {
559     return QFile::decodeName(mnt.mnt_dir);
560 }
561 
fileSystemType() const562 inline QByteArray QStorageIterator::fileSystemType() const
563 {
564     return QByteArray(mnt.mnt_type);
565 }
566 
device() const567 inline QByteArray QStorageIterator::device() const
568 {
569     // check that the device exists
570     if (mnt.mnt_fsname[0] == '/' && access(mnt.mnt_fsname, F_OK) != 0) {
571         // It doesn't, so let's try to resolve the dev_t from /dev/block.
572         // Note how strlen("4294967295") == digits10 + 1, so we need to add 1
573         // for each number, plus the ':'.
574         char buf[sizeof("/dev/block/") + 2 * std::numeric_limits<unsigned>::digits10 + 3];
575         QByteArray dev(PATH_MAX, Qt::Uninitialized);
576         char *devdata = dev.data();
577 
578         snprintf(buf, sizeof(buf), "/dev/block/%u:%u", major(mnt.rdev), minor(mnt.rdev));
579         if (realpath(buf, devdata)) {
580             dev.truncate(strlen(devdata));
581             return dev;
582         }
583     }
584     return QByteArray(mnt.mnt_fsname);
585 }
586 
options() const587 inline QByteArray QStorageIterator::options() const
588 {
589     // Merge the two options, starting with the superblock options and letting
590     // the per-mount options override.
591     const char *superopts = mnt.superopts;
592 
593     // Both mnt_opts and superopts start with "ro" or "rw", so we can skip the
594     // superblock's field (see show_mountinfo() in fs/proc_namespace.c).
595     if (superopts && superopts[0] == 'r') {
596         if (superopts[2] == '\0')       // no other superopts besides "ro" / "rw"?
597             superopts = nullptr;
598         else if (superopts[2] == ',')
599             superopts += 3;
600     }
601 
602     if (superopts)
603         return QByteArray(superopts) + ',' + mnt.mnt_opts;
604     return QByteArray(mnt.mnt_opts);
605 }
606 
subvolume() const607 inline QByteArray QStorageIterator::subvolume() const
608 {
609     return QByteArray(mnt.subvolume);
610 }
611 #elif defined(Q_OS_HAIKU)
QStorageIterator()612 inline QStorageIterator::QStorageIterator()
613 {
614 }
615 
~QStorageIterator()616 inline QStorageIterator::~QStorageIterator()
617 {
618 }
619 
isValid() const620 inline bool QStorageIterator::isValid() const
621 {
622     return true;
623 }
624 
next()625 inline bool QStorageIterator::next()
626 {
627     BVolume volume;
628 
629     if (m_volumeRoster.GetNextVolume(&volume) != B_OK)
630         return false;
631 
632     BDirectory directory;
633     if (volume.GetRootDirectory(&directory) != B_OK)
634         return false;
635 
636     const BPath path(&directory);
637 
638     fs_info fsInfo;
639     memset(&fsInfo, 0, sizeof(fsInfo));
640 
641     if (fs_stat_dev(volume.Device(), &fsInfo) != 0)
642         return false;
643 
644     m_rootPath = path.Path();
645     m_fileSystemType = QByteArray(fsInfo.fsh_name);
646 
647     const QByteArray deviceName(fsInfo.device_name);
648     m_device = (deviceName.isEmpty() ? QByteArray::number(qint32(volume.Device())) : deviceName);
649 
650     return true;
651 }
652 
rootPath() const653 inline QString QStorageIterator::rootPath() const
654 {
655     return QFile::decodeName(m_rootPath);
656 }
657 
fileSystemType() const658 inline QByteArray QStorageIterator::fileSystemType() const
659 {
660     return m_fileSystemType;
661 }
662 
device() const663 inline QByteArray QStorageIterator::device() const
664 {
665     return m_device;
666 }
667 
options() const668 inline QByteArray QStorageIterator::options() const
669 {
670     return QByteArray();
671 }
672 
subvolume() const673 inline QByteArray QStorageIterator::subvolume() const
674 {
675     return QByteArray();
676 }
677 #else
678 
QStorageIterator()679 inline QStorageIterator::QStorageIterator()
680 {
681 }
682 
~QStorageIterator()683 inline QStorageIterator::~QStorageIterator()
684 {
685 }
686 
isValid() const687 inline bool QStorageIterator::isValid() const
688 {
689     return false;
690 }
691 
next()692 inline bool QStorageIterator::next()
693 {
694     return false;
695 }
696 
rootPath() const697 inline QString QStorageIterator::rootPath() const
698 {
699     return QString();
700 }
701 
fileSystemType() const702 inline QByteArray QStorageIterator::fileSystemType() const
703 {
704     return QByteArray();
705 }
706 
device() const707 inline QByteArray QStorageIterator::device() const
708 {
709     return QByteArray();
710 }
711 
options() const712 inline QByteArray QStorageIterator::options() const
713 {
714     return QByteArray();
715 }
716 
subvolume() const717 inline QByteArray QStorageIterator::subvolume() const
718 {
719     return QByteArray();
720 }
721 #endif
722 
initRootPath()723 void QStorageInfoPrivate::initRootPath()
724 {
725     rootPath = QFileInfo(rootPath).canonicalFilePath();
726 
727     if (rootPath.isEmpty())
728         return;
729 
730     QStorageIterator it;
731     if (!it.isValid()) {
732         rootPath = QStringLiteral("/");
733         return;
734     }
735 
736     int maxLength = 0;
737     const QString oldRootPath = rootPath;
738     rootPath.clear();
739 
740     while (it.next()) {
741         const QString mountDir = it.rootPath();
742         const QByteArray fsName = it.fileSystemType();
743         // we try to find most suitable entry
744         if (isParentOf(mountDir, oldRootPath) && maxLength < mountDir.length()) {
745             maxLength = mountDir.length();
746             rootPath = mountDir;
747             device = it.device();
748             fileSystemType = fsName;
749             subvolume = it.subvolume();
750         }
751     }
752 }
753 
754 #ifdef Q_OS_LINUX
755 // udev encodes the labels with ID_LABEL_FS_ENC which is done with
756 // blkid_encode_string(). Within this function some 1-byte utf-8
757 // characters not considered safe (e.g. '\' or ' ') are encoded as hex
decodeFsEncString(const QString & str)758 static QString decodeFsEncString(const QString &str)
759 {
760     QString decoded;
761     decoded.reserve(str.size());
762 
763     int i = 0;
764     while (i < str.size()) {
765         if (i <= str.size() - 4) {    // we need at least four characters \xAB
766             if (str.at(i) == QLatin1Char('\\') &&
767                 str.at(i+1) == QLatin1Char('x')) {
768                 bool bOk;
769                 const int code = str.midRef(i+2, 2).toInt(&bOk, 16);
770                 // only decode characters between 0x20 and 0x7f but not
771                 // the backslash to prevent collisions
772                 if (bOk && code >= 0x20 && code < 0x80 && code != '\\') {
773                     decoded += QChar(code);
774                     i += 4;
775                     continue;
776                 }
777             }
778         }
779         decoded += str.at(i);
780         ++i;
781     }
782     return decoded;
783 }
784 #endif
785 
retrieveLabel(const QByteArray & device)786 static inline QString retrieveLabel(const QByteArray &device)
787 {
788 #ifdef Q_OS_LINUX
789     static const char pathDiskByLabel[] = "/dev/disk/by-label";
790 
791     QFileInfo devinfo(QFile::decodeName(device));
792     QString devicePath = devinfo.canonicalFilePath();
793 
794     QDirIterator it(QLatin1String(pathDiskByLabel), QDir::NoDotAndDotDot);
795     while (it.hasNext()) {
796         it.next();
797         QFileInfo fileInfo(it.fileInfo());
798         if (fileInfo.isSymLink() && fileInfo.symLinkTarget() == devicePath)
799             return decodeFsEncString(fileInfo.fileName());
800     }
801 #elif defined Q_OS_HAIKU
802     fs_info fsInfo;
803     memset(&fsInfo, 0, sizeof(fsInfo));
804 
805     int32 pos = 0;
806     dev_t dev;
807     while ((dev = next_dev(&pos)) >= 0) {
808         if (fs_stat_dev(dev, &fsInfo) != 0)
809             continue;
810 
811         if (qstrcmp(fsInfo.device_name, device.constData()) == 0)
812             return QString::fromLocal8Bit(fsInfo.volume_name);
813     }
814 #else
815     Q_UNUSED(device);
816 #endif
817 
818     return QString();
819 }
820 
doStat()821 void QStorageInfoPrivate::doStat()
822 {
823     initRootPath();
824     if (rootPath.isEmpty())
825         return;
826 
827     retrieveVolumeInfo();
828     name = retrieveLabel(device);
829 }
830 
retrieveVolumeInfo()831 void QStorageInfoPrivate::retrieveVolumeInfo()
832 {
833     QT_STATFSBUF statfs_buf;
834     int result;
835     EINTR_LOOP(result, QT_STATFS(QFile::encodeName(rootPath).constData(), &statfs_buf));
836     if (result == 0) {
837         valid = true;
838         ready = true;
839 
840 #if defined(Q_OS_INTEGRITY) || (defined(Q_OS_BSD4) && !defined(Q_OS_NETBSD)) || defined(Q_OS_RTEMS)
841         bytesTotal = statfs_buf.f_blocks * statfs_buf.f_bsize;
842         bytesFree = statfs_buf.f_bfree * statfs_buf.f_bsize;
843         bytesAvailable = statfs_buf.f_bavail * statfs_buf.f_bsize;
844 #else
845         bytesTotal = statfs_buf.f_blocks * statfs_buf.f_frsize;
846         bytesFree = statfs_buf.f_bfree * statfs_buf.f_frsize;
847         bytesAvailable = statfs_buf.f_bavail * statfs_buf.f_frsize;
848 #endif
849         blockSize = statfs_buf.f_bsize;
850 #if defined(Q_OS_ANDROID) || defined(Q_OS_BSD4) || defined(Q_OS_INTEGRITY) || defined(Q_OS_RTEMS)
851 #if defined(_STATFS_F_FLAGS)
852         readOnly = (statfs_buf.f_flags & ST_RDONLY) != 0;
853 #endif
854 #else
855         readOnly = (statfs_buf.f_flag & ST_RDONLY) != 0;
856 #endif
857     }
858 }
859 
mountedVolumes()860 QList<QStorageInfo> QStorageInfoPrivate::mountedVolumes()
861 {
862     QStorageIterator it;
863     if (!it.isValid())
864         return QList<QStorageInfo>() << root();
865 
866     QList<QStorageInfo> volumes;
867 
868     while (it.next()) {
869         if (!shouldIncludeFs(it))
870             continue;
871 
872         const QString mountDir = it.rootPath();
873         QStorageInfo info(mountDir);
874         info.d->device = it.device();
875         info.d->fileSystemType = it.fileSystemType();
876         info.d->subvolume = it.subvolume();
877         if (info.bytesTotal() == 0 && info != root())
878             continue;
879         volumes.append(info);
880     }
881 
882     return volumes;
883 }
884 
root()885 QStorageInfo QStorageInfoPrivate::root()
886 {
887     return QStorageInfo(QStringLiteral("/"));
888 }
889 
890 QT_END_NAMESPACE
891