1 //===- llvm/Support/Unix/Path.inc - Unix Path Implementation ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Unix specific implementation of the Path API.
12 //===----------------------------------------------------------------------===//
14 //===----------------------------------------------------------------------===//
15 //=== WARNING: Implementation here must contain only generic UNIX code that
16 //=== is guaranteed to work on *all* UNIX variants.
17 //===----------------------------------------------------------------------===//
31 #ifdef HAVE_SYS_MMAN_H
36 # define NAMLEN(dirent) strlen((dirent)->d_name)
38 # define dirent direct
39 # define NAMLEN(dirent) (dirent)->d_namlen
41 # include <sys/ndir.h>
54 #include <mach-o/dyld.h>
58 // Both stdio.h and cstdio are included via different paths and
59 // stdcxx's cstdio doesn't include stdio.h, so it doesn't #undef the macros
65 #if defined(__GNU__) && !defined(PATH_MAX)
66 # define PATH_MAX 4096
69 #include <sys/types.h>
70 #if !defined(__APPLE__) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && \
72 #include <sys/statvfs.h>
73 #define STATVFS statvfs
74 #define FSTATVFS fstatvfs
75 #define STATVFS_F_FRSIZE(vfs) vfs.f_frsize
77 #if defined(__OpenBSD__) || defined(__FreeBSD__)
78 #include <sys/param.h>
79 #include <sys/mount.h>
80 #elif defined(__linux__)
81 #if defined(HAVE_LINUX_MAGIC_H)
82 #include <linux/magic.h>
84 #if defined(HAVE_LINUX_NFS_FS_H)
85 #include <linux/nfs_fs.h>
87 #if defined(HAVE_LINUX_SMB_H)
88 #include <linux/smb.h>
93 #include <sys/mount.h>
95 #define STATVFS statfs
96 #define FSTATVFS fstatfs
97 #define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
100 #if defined(__NetBSD__)
101 #define STATVFS_F_FLAG(vfs) (vfs).f_flag
103 #define STATVFS_F_FLAG(vfs) (vfs).f_flags
106 using namespace llvm;
111 #if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
112 defined(__OpenBSD__) || defined(__minix) || defined(__FreeBSD_kernel__) || \
113 defined(__linux__) || defined(__CYGWIN__) || defined(__DragonFly__) || \
116 test_dir(char ret[PATH_MAX], const char *dir, const char *bin)
119 char fullpath[PATH_MAX];
121 snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin);
122 if (!realpath(fullpath, ret))
124 if (stat(fullpath, &sb) != 0)
131 getprogpath(char ret[PATH_MAX], const char *bin)
135 /* First approach: absolute path. */
137 if (test_dir(ret, "/", bin) == 0)
142 /* Second approach: relative path. */
143 if (strchr(bin, '/')) {
145 if (!getcwd(cwd, PATH_MAX))
147 if (test_dir(ret, cwd, bin) == 0)
152 /* Third approach: $PATH */
153 if ((pv = getenv("PATH")) == nullptr)
158 while ((t = strsep(&s, ":")) != nullptr) {
159 if (test_dir(ret, t, bin) == 0) {
167 #endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
169 /// GetMainExecutable - Return the path to the main executable, given the
170 /// value of argv[0] from program startup.
171 std::string getMainExecutable(const char *argv0, void *MainAddr) {
172 #if defined(__APPLE__)
173 // On OS X the executable path is saved to the stack by dyld. Reading it
174 // from there is much faster than calling dladdr, especially for large
175 // binaries with symbols.
176 char exe_path[MAXPATHLEN];
177 uint32_t size = sizeof(exe_path);
178 if (_NSGetExecutablePath(exe_path, &size) == 0) {
179 char link_path[MAXPATHLEN];
180 if (realpath(exe_path, link_path))
183 #elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
184 defined(__OpenBSD__) || defined(__minix) || defined(__DragonFly__) || \
185 defined(__FreeBSD_kernel__) || defined(_AIX)
186 char exe_path[PATH_MAX];
188 if (getprogpath(exe_path, argv0) != NULL)
190 #elif defined(__linux__) || defined(__CYGWIN__)
191 char exe_path[MAXPATHLEN];
192 StringRef aPath("/proc/self/exe");
193 if (sys::fs::exists(aPath)) {
194 // /proc is not always mounted under Linux (chroot for example).
195 ssize_t len = readlink(aPath.str().c_str(), exe_path, sizeof(exe_path));
197 return std::string(exe_path, len);
199 // Fall back to the classical detection.
200 if (getprogpath(exe_path, argv0))
203 #elif defined(HAVE_DLFCN_H) && defined(HAVE_DLADDR)
204 // Use dladdr to get executable path if available.
206 int err = dladdr(MainAddr, &DLInfo);
210 // If the filename is a symlink, we need to resolve and return the location of
211 // the actual executable.
212 char link_path[MAXPATHLEN];
213 if (realpath(DLInfo.dli_fname, link_path))
216 #error GetMainExecutable is not implemented on this host yet.
221 TimePoint<> file_status::getLastAccessedTime() const {
222 return toTimePoint(fs_st_atime);
225 TimePoint<> file_status::getLastModificationTime() const {
226 return toTimePoint(fs_st_mtime);
229 UniqueID file_status::getUniqueID() const {
230 return UniqueID(fs_st_dev, fs_st_ino);
233 uint32_t file_status::getLinkCount() const {
237 ErrorOr<space_info> disk_space(const Twine &Path) {
239 if (::STATVFS(Path.str().c_str(), &Vfs))
240 return std::error_code(errno, std::generic_category());
241 auto FrSize = STATVFS_F_FRSIZE(Vfs);
242 space_info SpaceInfo;
243 SpaceInfo.capacity = static_cast<uint64_t>(Vfs.f_blocks) * FrSize;
244 SpaceInfo.free = static_cast<uint64_t>(Vfs.f_bfree) * FrSize;
245 SpaceInfo.available = static_cast<uint64_t>(Vfs.f_bavail) * FrSize;
249 std::error_code current_path(SmallVectorImpl<char> &result) {
252 const char *pwd = ::getenv("PWD");
253 llvm::sys::fs::file_status PWDStatus, DotStatus;
254 if (pwd && llvm::sys::path::is_absolute(pwd) &&
255 !llvm::sys::fs::status(pwd, PWDStatus) &&
256 !llvm::sys::fs::status(".", DotStatus) &&
257 PWDStatus.getUniqueID() == DotStatus.getUniqueID()) {
258 result.append(pwd, pwd + strlen(pwd));
259 return std::error_code();
263 result.reserve(MAXPATHLEN);
266 result.reserve(1024);
270 if (::getcwd(result.data(), result.capacity()) == nullptr) {
271 // See if there was a real error.
273 return std::error_code(errno, std::generic_category());
274 // Otherwise there just wasn't enough space.
275 result.reserve(result.capacity() * 2);
280 result.set_size(strlen(result.data()));
281 return std::error_code();
284 std::error_code set_current_path(const Twine &path) {
285 SmallString<128> path_storage;
286 StringRef p = path.toNullTerminatedStringRef(path_storage);
288 if (::chdir(p.begin()) == -1)
289 return std::error_code(errno, std::generic_category());
291 return std::error_code();
294 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
296 SmallString<128> path_storage;
297 StringRef p = path.toNullTerminatedStringRef(path_storage);
299 if (::mkdir(p.begin(), Perms) == -1) {
300 if (errno != EEXIST || !IgnoreExisting)
301 return std::error_code(errno, std::generic_category());
304 return std::error_code();
307 // Note that we are using symbolic link because hard links are not supported by
308 // all filesystems (SMB doesn't).
309 std::error_code create_link(const Twine &to, const Twine &from) {
311 SmallString<128> from_storage;
312 SmallString<128> to_storage;
313 StringRef f = from.toNullTerminatedStringRef(from_storage);
314 StringRef t = to.toNullTerminatedStringRef(to_storage);
316 if (::symlink(t.begin(), f.begin()) == -1)
317 return std::error_code(errno, std::generic_category());
319 return std::error_code();
322 std::error_code create_hard_link(const Twine &to, const Twine &from) {
324 SmallString<128> from_storage;
325 SmallString<128> to_storage;
326 StringRef f = from.toNullTerminatedStringRef(from_storage);
327 StringRef t = to.toNullTerminatedStringRef(to_storage);
329 if (::link(t.begin(), f.begin()) == -1)
330 return std::error_code(errno, std::generic_category());
332 return std::error_code();
335 std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
336 SmallString<128> path_storage;
337 StringRef p = path.toNullTerminatedStringRef(path_storage);
340 if (lstat(p.begin(), &buf) != 0) {
341 if (errno != ENOENT || !IgnoreNonExisting)
342 return std::error_code(errno, std::generic_category());
343 return std::error_code();
346 // Note: this check catches strange situations. In all cases, LLVM should
347 // only be involved in the creation and deletion of regular files. This
348 // check ensures that what we're trying to erase is a regular file. It
349 // effectively prevents LLVM from erasing things like /dev/null, any block
350 // special file, or other things that aren't "regular" files.
351 if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode))
352 return make_error_code(errc::operation_not_permitted);
354 if (::remove(p.begin()) == -1) {
355 if (errno != ENOENT || !IgnoreNonExisting)
356 return std::error_code(errno, std::generic_category());
359 return std::error_code();
362 static bool is_local_impl(struct STATVFS &Vfs) {
363 #if defined(__linux__)
364 #ifndef NFS_SUPER_MAGIC
365 #define NFS_SUPER_MAGIC 0x6969
367 #ifndef SMB_SUPER_MAGIC
368 #define SMB_SUPER_MAGIC 0x517B
370 #ifndef CIFS_MAGIC_NUMBER
371 #define CIFS_MAGIC_NUMBER 0xFF534D42
373 switch ((uint32_t)Vfs.f_type) {
374 case NFS_SUPER_MAGIC:
375 case SMB_SUPER_MAGIC:
376 case CIFS_MAGIC_NUMBER:
381 #elif defined(__CYGWIN__)
382 // Cygwin doesn't expose this information; would need to use Win32 API.
385 return !!(STATVFS_F_FLAG(Vfs) & MNT_LOCAL);
389 std::error_code is_local(const Twine &Path, bool &Result) {
391 if (::STATVFS(Path.str().c_str(), &Vfs))
392 return std::error_code(errno, std::generic_category());
394 Result = is_local_impl(Vfs);
395 return std::error_code();
398 std::error_code is_local(int FD, bool &Result) {
400 if (::FSTATVFS(FD, &Vfs))
401 return std::error_code(errno, std::generic_category());
403 Result = is_local_impl(Vfs);
404 return std::error_code();
407 std::error_code rename(const Twine &from, const Twine &to) {
409 SmallString<128> from_storage;
410 SmallString<128> to_storage;
411 StringRef f = from.toNullTerminatedStringRef(from_storage);
412 StringRef t = to.toNullTerminatedStringRef(to_storage);
414 if (::rename(f.begin(), t.begin()) == -1)
415 return std::error_code(errno, std::generic_category());
417 return std::error_code();
420 std::error_code resize_file(int FD, uint64_t Size) {
421 #if defined(HAVE_POSIX_FALLOCATE)
422 // If we have posix_fallocate use it. Unlike ftruncate it always allocates
423 // space, so we get an error if the disk is full.
424 if (int Err = ::posix_fallocate(FD, 0, Size)) {
425 if (Err != EOPNOTSUPP)
426 return std::error_code(Err, std::generic_category());
429 // Use ftruncate as a fallback. It may or may not allocate space. At least on
430 // OS X with HFS+ it does.
431 if (::ftruncate(FD, Size) == -1)
432 return std::error_code(errno, std::generic_category());
434 return std::error_code();
437 static int convertAccessMode(AccessMode Mode) {
439 case AccessMode::Exist:
441 case AccessMode::Write:
443 case AccessMode::Execute:
444 return R_OK | X_OK; // scripts also need R_OK.
446 llvm_unreachable("invalid enum");
449 std::error_code access(const Twine &Path, AccessMode Mode) {
450 SmallString<128> PathStorage;
451 StringRef P = Path.toNullTerminatedStringRef(PathStorage);
453 if (::access(P.begin(), convertAccessMode(Mode)) == -1)
454 return std::error_code(errno, std::generic_category());
456 if (Mode == AccessMode::Execute) {
457 // Don't say that directories are executable.
459 if (0 != stat(P.begin(), &buf))
460 return errc::permission_denied;
461 if (!S_ISREG(buf.st_mode))
462 return errc::permission_denied;
465 return std::error_code();
468 bool can_execute(const Twine &Path) {
469 return !access(Path, AccessMode::Execute);
472 bool equivalent(file_status A, file_status B) {
473 assert(status_known(A) && status_known(B));
474 return A.fs_st_dev == B.fs_st_dev &&
475 A.fs_st_ino == B.fs_st_ino;
478 std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
479 file_status fsA, fsB;
480 if (std::error_code ec = status(A, fsA))
482 if (std::error_code ec = status(B, fsB))
484 result = equivalent(fsA, fsB);
485 return std::error_code();
488 static void expandTildeExpr(SmallVectorImpl<char> &Path) {
489 StringRef PathStr(Path.begin(), Path.size());
490 if (PathStr.empty() || !PathStr.startswith("~"))
493 PathStr = PathStr.drop_front();
495 PathStr.take_until([](char c) { return path::is_separator(c); });
496 StringRef Remainder = PathStr.substr(Expr.size() + 1);
497 SmallString<128> Storage;
499 // This is just ~/..., resolve it to the current user's home dir.
500 if (!path::home_directory(Storage)) {
501 // For some reason we couldn't get the home directory. Just exit.
505 // Overwrite the first character and insert the rest.
506 Path[0] = Storage[0];
507 Path.insert(Path.begin() + 1, Storage.begin() + 1, Storage.end());
511 // This is a string of the form ~username/, look up this user's entry in the
512 // password database.
513 struct passwd *Entry = nullptr;
514 std::string User = Expr.str();
515 Entry = ::getpwnam(User.c_str());
518 // Unable to look up the entry, just return back the original path.
524 Path.append(Entry->pw_dir, Entry->pw_dir + strlen(Entry->pw_dir));
525 llvm::sys::path::append(Path, Storage);
528 static std::error_code fillStatus(int StatRet, const struct stat &Status,
529 file_status &Result) {
531 std::error_code ec(errno, std::generic_category());
532 if (ec == errc::no_such_file_or_directory)
533 Result = file_status(file_type::file_not_found);
535 Result = file_status(file_type::status_error);
539 file_type Type = file_type::type_unknown;
541 if (S_ISDIR(Status.st_mode))
542 Type = file_type::directory_file;
543 else if (S_ISREG(Status.st_mode))
544 Type = file_type::regular_file;
545 else if (S_ISBLK(Status.st_mode))
546 Type = file_type::block_file;
547 else if (S_ISCHR(Status.st_mode))
548 Type = file_type::character_file;
549 else if (S_ISFIFO(Status.st_mode))
550 Type = file_type::fifo_file;
551 else if (S_ISSOCK(Status.st_mode))
552 Type = file_type::socket_file;
553 else if (S_ISLNK(Status.st_mode))
554 Type = file_type::symlink_file;
556 perms Perms = static_cast<perms>(Status.st_mode) & all_perms;
557 Result = file_status(Type, Perms, Status.st_dev, Status.st_nlink,
558 Status.st_ino, Status.st_atime, Status.st_mtime,
559 Status.st_uid, Status.st_gid, Status.st_size);
561 return std::error_code();
564 std::error_code status(const Twine &Path, file_status &Result, bool Follow) {
565 SmallString<128> PathStorage;
566 StringRef P = Path.toNullTerminatedStringRef(PathStorage);
569 int StatRet = (Follow ? ::stat : ::lstat)(P.begin(), &Status);
570 return fillStatus(StatRet, Status, Result);
573 std::error_code status(int FD, file_status &Result) {
575 int StatRet = ::fstat(FD, &Status);
576 return fillStatus(StatRet, Status, Result);
579 std::error_code setPermissions(const Twine &Path, perms Permissions) {
580 SmallString<128> PathStorage;
581 StringRef P = Path.toNullTerminatedStringRef(PathStorage);
583 if (::chmod(P.begin(), Permissions))
584 return std::error_code(errno, std::generic_category());
585 return std::error_code();
588 std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) {
589 #if defined(HAVE_FUTIMENS)
591 Times[0] = Times[1] = sys::toTimeSpec(Time);
592 if (::futimens(FD, Times))
593 return std::error_code(errno, std::generic_category());
594 return std::error_code();
595 #elif defined(HAVE_FUTIMES)
597 Times[0] = Times[1] = sys::toTimeVal(
598 std::chrono::time_point_cast<std::chrono::microseconds>(Time));
599 if (::futimes(FD, Times))
600 return std::error_code(errno, std::generic_category());
601 return std::error_code();
603 #warning Missing futimes() and futimens()
604 return make_error_code(errc::function_not_supported);
608 std::error_code mapped_file_region::init(int FD, uint64_t Offset,
612 int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
613 int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
614 #if defined(__APPLE__)
615 //----------------------------------------------------------------------
616 // Newer versions of MacOSX have a flag that will allow us to read from
617 // binaries whose code signature is invalid without crashing by using
618 // the MAP_RESILIENT_CODESIGN flag. Also if a file from removable media
619 // is mapped we can avoid crashing and return zeroes to any pages we try
620 // to read if the media becomes unavailable by using the
621 // MAP_RESILIENT_MEDIA flag. These flags are only usable when mapping
622 // with PROT_READ, so take care not to specify them otherwise.
623 //----------------------------------------------------------------------
624 if (Mode == readonly) {
625 #if defined(MAP_RESILIENT_CODESIGN)
626 flags |= MAP_RESILIENT_CODESIGN;
628 #if defined(MAP_RESILIENT_MEDIA)
629 flags |= MAP_RESILIENT_MEDIA;
632 #endif // #if defined (__APPLE__)
634 Mapping = ::mmap(nullptr, Size, prot, flags, FD, Offset);
635 if (Mapping == MAP_FAILED)
636 return std::error_code(errno, std::generic_category());
637 return std::error_code();
640 mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length,
641 uint64_t offset, std::error_code &ec)
642 : Size(length), Mapping() {
643 // Make sure that the requested size fits within SIZE_T.
644 if (length > std::numeric_limits<size_t>::max()) {
645 ec = make_error_code(errc::invalid_argument);
649 ec = init(fd, offset, mode);
654 mapped_file_region::~mapped_file_region() {
656 ::munmap(Mapping, Size);
659 uint64_t mapped_file_region::size() const {
660 assert(Mapping && "Mapping failed but used anyway!");
664 char *mapped_file_region::data() const {
665 assert(Mapping && "Mapping failed but used anyway!");
666 return reinterpret_cast<char*>(Mapping);
669 const char *mapped_file_region::const_data() const {
670 assert(Mapping && "Mapping failed but used anyway!");
671 return reinterpret_cast<const char*>(Mapping);
674 int mapped_file_region::alignment() {
675 return Process::getPageSize();
678 std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
680 bool follow_symlinks) {
681 SmallString<128> path_null(path);
682 DIR *directory = ::opendir(path_null.c_str());
684 return std::error_code(errno, std::generic_category());
686 it.IterationHandle = reinterpret_cast<intptr_t>(directory);
687 // Add something for replace_filename to replace.
688 path::append(path_null, ".");
689 it.CurrentEntry = directory_entry(path_null.str(), follow_symlinks);
690 return directory_iterator_increment(it);
693 std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
694 if (it.IterationHandle)
695 ::closedir(reinterpret_cast<DIR *>(it.IterationHandle));
696 it.IterationHandle = 0;
697 it.CurrentEntry = directory_entry();
698 return std::error_code();
701 std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
703 dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle));
704 if (cur_dir == nullptr && errno != 0) {
705 return std::error_code(errno, std::generic_category());
706 } else if (cur_dir != nullptr) {
707 StringRef name(cur_dir->d_name, NAMLEN(cur_dir));
708 if ((name.size() == 1 && name[0] == '.') ||
709 (name.size() == 2 && name[0] == '.' && name[1] == '.'))
710 return directory_iterator_increment(it);
711 it.CurrentEntry.replace_filename(name);
713 return directory_iterator_destruct(it);
715 return std::error_code();
718 #if !defined(F_GETPATH)
719 static bool hasProcSelfFD() {
720 // If we have a /proc filesystem mounted, we can quickly establish the
721 // real name of the file with readlink
722 static const bool Result = (::access("/proc/self/fd", R_OK) == 0);
727 std::error_code openFileForRead(const Twine &Name, int &ResultFD,
728 SmallVectorImpl<char> *RealPath) {
729 SmallString<128> Storage;
730 StringRef P = Name.toNullTerminatedStringRef(Storage);
731 int OpenFlags = O_RDONLY;
733 OpenFlags |= O_CLOEXEC;
735 while ((ResultFD = open(P.begin(), OpenFlags)) < 0) {
737 return std::error_code(errno, std::generic_category());
740 int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC);
742 assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed");
744 // Attempt to get the real name of the file, if the user asked
746 return std::error_code();
748 #if defined(F_GETPATH)
749 // When F_GETPATH is availble, it is the quickest way to get
750 // the real path name.
751 char Buffer[MAXPATHLEN];
752 if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1)
753 RealPath->append(Buffer, Buffer + strlen(Buffer));
755 char Buffer[PATH_MAX];
756 if (hasProcSelfFD()) {
758 snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
759 ssize_t CharCount = ::readlink(ProcPath, Buffer, sizeof(Buffer));
761 RealPath->append(Buffer, Buffer + CharCount);
763 // Use ::realpath to get the real path name
764 if (::realpath(P.begin(), Buffer) != nullptr)
765 RealPath->append(Buffer, Buffer + strlen(Buffer));
768 return std::error_code();
771 std::error_code openFileForWrite(const Twine &Name, int &ResultFD,
772 sys::fs::OpenFlags Flags, unsigned Mode) {
773 // Verify that we don't have both "append" and "excl".
774 assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
775 "Cannot specify both 'excl' and 'append' file creation flags!");
777 int OpenFlags = O_CREAT;
780 OpenFlags |= O_CLOEXEC;
786 OpenFlags |= O_WRONLY;
788 if (Flags & F_Append)
789 OpenFlags |= O_APPEND;
791 OpenFlags |= O_TRUNC;
796 SmallString<128> Storage;
797 StringRef P = Name.toNullTerminatedStringRef(Storage);
798 while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) {
800 return std::error_code(errno, std::generic_category());
803 int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC);
805 assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed");
807 return std::error_code();
810 std::error_code getPathFromOpenFD(int FD, SmallVectorImpl<char> &ResultPath) {
812 return make_error_code(errc::bad_file_descriptor);
814 #if defined(F_GETPATH)
815 // When F_GETPATH is availble, it is the quickest way to get
816 // the path from a file descriptor.
817 ResultPath.reserve(MAXPATHLEN);
818 if (::fcntl(FD, F_GETPATH, ResultPath.begin()) == -1)
819 return std::error_code(errno, std::generic_category());
821 ResultPath.set_size(strlen(ResultPath.begin()));
823 // If we have a /proc filesystem mounted, we can quickly establish the
824 // real name of the file with readlink. Otherwise, we don't know how to
825 // get the filename from a file descriptor. Give up.
826 if (!fs::hasProcSelfFD())
827 return make_error_code(errc::function_not_supported);
829 ResultPath.reserve(PATH_MAX);
831 snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", FD);
832 ssize_t CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
834 return std::error_code(errno, std::generic_category());
836 // Was the filename truncated?
837 if (static_cast<size_t>(CharCount) == ResultPath.capacity()) {
838 // Use lstat to get the size of the filename
840 if (::lstat(ProcPath, &sb) < 0)
841 return std::error_code(errno, std::generic_category());
843 ResultPath.reserve(sb.st_size + 1);
844 CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
846 return std::error_code(errno, std::generic_category());
848 // Test for race condition: did the link size change?
849 if (CharCount > sb.st_size)
850 return std::error_code(ENAMETOOLONG, std::generic_category());
852 ResultPath.set_size(static_cast<size_t>(CharCount));
854 return std::error_code();
857 template <typename T>
858 static std::error_code remove_directories_impl(const T &Entry,
861 directory_iterator Begin(Entry, EC, false);
862 directory_iterator End;
863 while (Begin != End) {
866 EC = Item.status(st);
867 if (EC && !IgnoreErrors)
870 if (is_directory(st)) {
871 EC = remove_directories_impl(Item, IgnoreErrors);
872 if (EC && !IgnoreErrors)
876 EC = fs::remove(Item.path(), true);
877 if (EC && !IgnoreErrors)
881 if (EC && !IgnoreErrors)
884 return std::error_code();
887 std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
888 auto EC = remove_directories_impl(path, IgnoreErrors);
889 if (EC && !IgnoreErrors)
891 EC = fs::remove(path, true);
892 if (EC && !IgnoreErrors)
894 return std::error_code();
897 std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,
900 if (path.isTriviallyEmpty())
901 return std::error_code();
904 SmallString<128> Storage;
905 path.toVector(Storage);
906 expandTildeExpr(Storage);
907 return real_path(Storage, dest, false);
911 std::error_code EC = openFileForRead(path, fd, &dest);
916 return std::error_code();
919 } // end namespace fs
923 bool home_directory(SmallVectorImpl<char> &result) {
924 char *RequestedDir = getenv("HOME");
926 struct passwd *pw = getpwuid(getuid());
927 if (pw && pw->pw_dir)
928 RequestedDir = pw->pw_dir;
934 result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
938 static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) {
939 #if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR)
940 // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR.
941 // macros defined in <unistd.h> on darwin >= 9
942 int ConfName = TempDir ? _CS_DARWIN_USER_TEMP_DIR
943 : _CS_DARWIN_USER_CACHE_DIR;
944 size_t ConfLen = confstr(ConfName, nullptr, 0);
947 Result.resize(ConfLen);
948 ConfLen = confstr(ConfName, Result.data(), Result.size());
949 } while (ConfLen > 0 && ConfLen != Result.size());
952 assert(Result.back() == 0);
963 static bool getUserCacheDir(SmallVectorImpl<char> &Result) {
964 // First try using XDG_CACHE_HOME env variable,
965 // as specified in XDG Base Directory Specification at
966 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
967 if (const char *XdgCacheDir = std::getenv("XDG_CACHE_HOME")) {
969 Result.append(XdgCacheDir, XdgCacheDir + strlen(XdgCacheDir));
973 // Try Darwin configuration query
974 if (getDarwinConfDir(false, Result))
977 // Use "$HOME/.cache" if $HOME is available
978 if (home_directory(Result)) {
979 append(Result, ".cache");
986 static const char *getEnvTempDir() {
987 // Check whether the temporary directory is specified by an environment
989 const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
990 for (const char *Env : EnvironmentVariables) {
991 if (const char *Dir = std::getenv(Env))
998 static const char *getDefaultTempDir(bool ErasedOnReboot) {
1009 void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
1012 if (ErasedOnReboot) {
1013 // There is no env variable for the cache directory.
1014 if (const char *RequestedDir = getEnvTempDir()) {
1015 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
1020 if (getDarwinConfDir(ErasedOnReboot, Result))
1023 const char *RequestedDir = getDefaultTempDir(ErasedOnReboot);
1024 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
1027 } // end namespace path
1029 } // end namespace sys
1030 } // end namespace llvm