diff options
Diffstat (limited to 'src/corelib/io/qstorageinfo_unix.cpp')
| -rw-r--r-- | src/corelib/io/qstorageinfo_unix.cpp | 255 |
1 files changed, 218 insertions, 37 deletions
diff --git a/src/corelib/io/qstorageinfo_unix.cpp b/src/corelib/io/qstorageinfo_unix.cpp index 1fc32e0f2d..7664b77d81 100644 --- a/src/corelib/io/qstorageinfo_unix.cpp +++ b/src/corelib/io/qstorageinfo_unix.cpp @@ -45,6 +45,7 @@ #include <QtCore/qtextstream.h> #include <QtCore/private/qcore_unix_p.h> +#include <QtCore/private/qlocale_tools_p.h> #include <errno.h> #include <sys/stat.h> @@ -107,6 +108,13 @@ # endif // QT_LARGEFILE_SUPPORT #endif // Q_OS_BSD4 +#if QT_HAS_INCLUDE(<paths.h>) +# include <paths.h> +#endif +#ifndef _PATH_MOUNTED +# define _PATH_MOUNTED "/etc/mnttab" +#endif + QT_BEGIN_NAMESPACE class QStorageIterator @@ -121,6 +129,7 @@ public: inline QByteArray fileSystemType() const; inline QByteArray device() const; inline QByteArray options() const; + inline QByteArray subvolume() const; private: #if defined(Q_OS_BSD4) QT_STATFSBUF *stat_buf; @@ -136,9 +145,36 @@ private: QByteArray m_device; QByteArray m_options; #elif defined(Q_OS_LINUX) || defined(Q_OS_HURD) + struct mountinfoent : public mntent { + // Details from proc(5) section from /proc/<pid>/mountinfo: + //(1) mount ID: a unique ID for the mount (may be reused after umount(2)). + int mount_id; + //(2) parent ID: the ID of the parent mount (or of self for the top of the mount tree). +// int parent_id; + //(3) major:minor: the value of st_dev for files on this filesystem (see stat(2)). +// dev_t rdev; + //(4) root: the pathname of the directory in the filesystem which forms the root of this mount. + char *subvolume; + //(5) mount point: the pathname of the mount point relative to the process's root directory. +// char *mnt_dir; // in mntent + //(6) mount options: per-mount options. +// char *mnt_opts; // in mntent + //(7) optional fields: zero or more fields of the form "tag[:value]"; see below. +// int flags; + //(8) separator: the end of the optional fields is marked by a single hyphen. + + //(9) filesystem type: the filesystem type in the form "type[.subtype]". +// char *mnt_type; // in mntent + //(10) mount source: filesystem-specific information or "none". +// char *mnt_fsname; // in mntent + //(11) super options: per-superblock options. + char *superopts; + }; + FILE *fp; - mntent mnt; QByteArray buffer; + mountinfoent mnt; + bool usingMountinfo; #elif defined(Q_OS_HAIKU) BVolumeRoster m_volumeRoster; @@ -239,13 +275,15 @@ inline QByteArray QStorageIterator::options() const return QByteArray(); } +inline QByteArray QStorageIterator::subvolume() const +{ + return QByteArray(); +} #elif defined(Q_OS_SOLARIS) -static const char pathMounted[] = "/etc/mnttab"; - inline QStorageIterator::QStorageIterator() { - const int fd = qt_safe_open(pathMounted, O_RDONLY); + const int fd = qt_safe_open(_PATH_MOUNTED, O_RDONLY); fp = ::fdopen(fd, "r"); } @@ -257,7 +295,7 @@ inline QStorageIterator::~QStorageIterator() inline bool QStorageIterator::isValid() const { - return fp != Q_NULLPTR; + return fp != nullptr; } inline bool QStorageIterator::next() @@ -280,13 +318,15 @@ inline QByteArray QStorageIterator::device() const return QByteArray(mnt.mnt_mntopts); } +inline QByteArray QStorageIterator::subvolume() const +{ + return QByteArray(); +} #elif defined(Q_OS_ANDROID) -static const QLatin1String pathMounted("/proc/mounts"); - inline QStorageIterator::QStorageIterator() { - file.setFileName(pathMounted); + file.setFileName(_PATH_MOUNTED); file.open(QIODevice::ReadOnly | QIODevice::Text); } @@ -337,32 +377,170 @@ inline QByteArray QStorageIterator::options() const return m_options; } +inline QByteArray QStorageIterator::subvolume() const +{ + return QByteArray(); +} #elif defined(Q_OS_LINUX) || defined(Q_OS_HURD) -static const char pathMounted[] = "/etc/mtab"; static const int bufferSize = 1024; // 2 paths (mount point+device) and metainfo; // should be enough inline QStorageIterator::QStorageIterator() : buffer(QByteArray(bufferSize, 0)) { - fp = ::setmntent(pathMounted, "r"); + fp = nullptr; + +#ifdef Q_OS_LINUX + // first, try to open /proc/self/mountinfo, which has more details + fp = ::fopen("/proc/self/mountinfo", "re"); +#endif + if (fp) { + usingMountinfo = true; + } else { + usingMountinfo = false; + fp = ::setmntent(_PATH_MOUNTED, "r"); + } } inline QStorageIterator::~QStorageIterator() { - if (fp) - ::endmntent(fp); + if (fp) { + if (usingMountinfo) + ::fclose(fp); + else + ::endmntent(fp); + } } inline bool QStorageIterator::isValid() const { - return fp != Q_NULLPTR; + return fp != nullptr; } inline bool QStorageIterator::next() { - return ::getmntent_r(fp, &mnt, buffer.data(), buffer.size()) != Q_NULLPTR; + mnt.subvolume = nullptr; + mnt.superopts = nullptr; + if (!usingMountinfo) + return ::getmntent_r(fp, &mnt, buffer.data(), buffer.size()) != nullptr; + + // Helper function to parse paths that the kernel inserts escape sequences + // for. The unescaped string is left at \a src and is properly + // NUL-terminated. Returns a pointer to the delimiter that terminated the + // path, or nullptr if it failed. + auto parseMangledPath = [](char *src) { + // The kernel escapes with octal the following characters: + // space ' ', tab '\t', backslask '\\', and newline '\n' + char *dst = src; + while (*src) { + switch (*src) { + case ' ': + // Unescaped space: end of the field. + *dst = '\0'; + return src; + + default: + *dst++ = *src++; + break; + + case '\\': + // It always uses exactly three octal characters. + ++src; + char c = (*src++ - '0') << 6; + c |= (*src++ - '0') << 3; + c |= (*src++ - '0'); + *dst++ = c; + break; + } + } + + // Found a NUL before the end of the field. + src = nullptr; + return src; + }; + + char *ptr = buffer.data(); + if (fgets(ptr, buffer.size(), fp) == nullptr) + return false; + + size_t len = strlen(buffer.data()); + if (len == 0) + return false; + if (ptr[len - 1] == '\n') + ptr[len - 1] = '\0'; + + // parse the line + bool ok; + mnt.mnt_freq = 0; + mnt.mnt_passno = 0; + + mnt.mount_id = qstrtoll(ptr, const_cast<const char **>(&ptr), 10, &ok); + if (!ptr || !ok) + return false; + + int parent_id = qstrtoll(ptr, const_cast<const char **>(&ptr), 10, &ok); + Q_UNUSED(parent_id); + if (!ptr || !ok) + return false; + + int rdevmajor = qstrtoll(ptr, const_cast<const char **>(&ptr), 10, &ok); + if (!ptr || !ok) + return false; + if (*ptr != ':') + return false; + int rdevminor = qstrtoll(ptr + 1, const_cast<const char **>(&ptr), 10, &ok); + if (!ptr || !ok) + return false; + Q_UNUSED(rdevmajor); + Q_UNUSED(rdevminor); + + if (*ptr != ' ') + return false; + + mnt.subvolume = ++ptr; + ptr = parseMangledPath(ptr); + if (!ptr) + return false; + + // unset a subvolume of "/" -- it's not a *sub* volume + if (mnt.subvolume + 1 == ptr) + *mnt.subvolume = '\0'; + + mnt.mnt_dir = ++ptr; + ptr = parseMangledPath(ptr); + if (!ptr) + return false; + + mnt.mnt_opts = ++ptr; + ptr = strchr(ptr, ' '); + if (!ptr) + return false; + + // we don't parse the flags, so just find the separator + if (char *const dashed = strstr(ptr, " - ")) { + *ptr = '\0'; + ptr = dashed + strlen(" - ") - 1; + } else { + return false; + } + + mnt.mnt_type = ++ptr; + ptr = strchr(ptr, ' '); + if (!ptr) + return false; + *ptr = '\0'; + + mnt.mnt_fsname = ++ptr; + ptr = parseMangledPath(ptr); + if (!ptr) + return false; + + mnt.superopts = ++ptr; + ptr += strcspn(ptr, " \n"); + *ptr = '\0'; + + return true; } inline QString QStorageIterator::rootPath() const @@ -382,9 +560,28 @@ inline QByteArray QStorageIterator::device() const inline QByteArray QStorageIterator::options() const { + // Merge the two options, starting with the superblock options and letting + // the per-mount options override. + const char *superopts = mnt.superopts; + + // Both mnt_opts and superopts start with "ro" or "rw", so we can skip the + // superblock's field (see show_mountinfo() in fs/proc_namespace.c). + if (superopts && superopts[0] == 'r') { + if (superopts[2] == '\0') // no other superopts besides "ro" / "rw"? + superopts = nullptr; + else if (superopts[2] == ',') + superopts += 3; + } + + if (superopts) + return QByteArray(superopts) + ',' + mnt.mnt_opts; return QByteArray(mnt.mnt_opts); } +inline QByteArray QStorageIterator::subvolume() const +{ + return QByteArray(mnt.subvolume); +} #elif defined(Q_OS_HAIKU) inline QStorageIterator::QStorageIterator() { @@ -447,6 +644,10 @@ inline QByteArray QStorageIterator::options() const return QByteArray(); } +inline QByteArray QStorageIterator::subvolume() const +{ + return QByteArray(); +} #else inline QStorageIterator::QStorageIterator() @@ -487,31 +688,11 @@ inline QByteArray QStorageIterator::options() const return QByteArray(); } -#endif - -static QByteArray extractSubvolume(const QStorageIterator &it) +inline QByteArray QStorageIterator::subvolume() const { -#ifdef Q_OS_LINUX - if (it.fileSystemType() == "btrfs") { - const QByteArrayList opts = it.options().split(','); - QByteArray id; - for (const QByteArray &opt : opts) { - static const char subvol[] = "subvol="; - static const char subvolid[] = "subvolid="; - if (opt.startsWith(subvol)) - return std::move(opt).mid(strlen(subvol)); - if (opt.startsWith(subvolid)) - id = std::move(opt).mid(strlen(subvolid)); - } - - // if we didn't find the subvolume name, return the subvolume ID - return id; - } -#else - Q_UNUSED(it); -#endif return QByteArray(); } +#endif void QStorageInfoPrivate::initRootPath() { @@ -539,7 +720,7 @@ void QStorageInfoPrivate::initRootPath() rootPath = mountDir; device = it.device(); fileSystemType = fsName; - subvolume = extractSubvolume(it); + subvolume = it.subvolume(); } } } |