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>
52 #include <mach-o/dyld.h>
56 // Both stdio.h and cstdio are included via different paths and
57 // stdcxx's cstdio doesn't include stdio.h, so it doesn't #undef the macros
63 #if defined(__GNU__) && !defined(PATH_MAX)
64 # define PATH_MAX 4096
67 #include <sys/types.h>
68 #if !defined(__APPLE__) && !defined(__OpenBSD__) && !defined(__ANDROID__)
69 #include <sys/statvfs.h>
70 #define STATVFS statvfs
71 #define STATVFS_F_FRSIZE(vfs) vfs.f_frsize
74 #include <sys/param.h>
75 #include <sys/mount.h>
76 #elif defined(__ANDROID__)
79 #include <sys/mount.h>
81 #define STATVFS statfs
82 #define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
91 #if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
92 defined(__OpenBSD__) || defined(__minix) || defined(__FreeBSD_kernel__) || \
93 defined(__linux__) || defined(__CYGWIN__) || defined(__DragonFly__) || \
96 test_dir(char ret[PATH_MAX], const char *dir, const char *bin)
99 char fullpath[PATH_MAX];
101 snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin);
102 if (!realpath(fullpath, ret))
104 if (stat(fullpath, &sb) != 0)
111 getprogpath(char ret[PATH_MAX], const char *bin)
115 /* First approach: absolute path. */
117 if (test_dir(ret, "/", bin) == 0)
122 /* Second approach: relative path. */
123 if (strchr(bin, '/')) {
125 if (!getcwd(cwd, PATH_MAX))
127 if (test_dir(ret, cwd, bin) == 0)
132 /* Third approach: $PATH */
133 if ((pv = getenv("PATH")) == nullptr)
138 while ((t = strsep(&s, ":")) != nullptr) {
139 if (test_dir(ret, t, bin) == 0) {
147 #endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
149 /// GetMainExecutable - Return the path to the main executable, given the
150 /// value of argv[0] from program startup.
151 std::string getMainExecutable(const char *argv0, void *MainAddr) {
152 #if defined(__APPLE__)
153 // On OS X the executable path is saved to the stack by dyld. Reading it
154 // from there is much faster than calling dladdr, especially for large
155 // binaries with symbols.
156 char exe_path[MAXPATHLEN];
157 uint32_t size = sizeof(exe_path);
158 if (_NSGetExecutablePath(exe_path, &size) == 0) {
159 char link_path[MAXPATHLEN];
160 if (realpath(exe_path, link_path))
163 #elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
164 defined(__OpenBSD__) || defined(__minix) || defined(__DragonFly__) || \
165 defined(__FreeBSD_kernel__) || defined(_AIX)
166 char exe_path[PATH_MAX];
168 if (getprogpath(exe_path, argv0) != NULL)
170 #elif defined(__linux__) || defined(__CYGWIN__)
171 char exe_path[MAXPATHLEN];
172 StringRef aPath("/proc/self/exe");
173 if (sys::fs::exists(aPath)) {
174 // /proc is not always mounted under Linux (chroot for example).
175 ssize_t len = readlink(aPath.str().c_str(), exe_path, sizeof(exe_path));
177 return std::string(exe_path, len);
179 // Fall back to the classical detection.
180 if (getprogpath(exe_path, argv0))
183 #elif defined(HAVE_DLFCN_H)
184 // Use dladdr to get executable path if available.
186 int err = dladdr(MainAddr, &DLInfo);
190 // If the filename is a symlink, we need to resolve and return the location of
191 // the actual executable.
192 char link_path[MAXPATHLEN];
193 if (realpath(DLInfo.dli_fname, link_path))
196 #error GetMainExecutable is not implemented on this host yet.
201 TimePoint<> file_status::getLastAccessedTime() const {
202 return toTimePoint(fs_st_atime);
205 TimePoint<> file_status::getLastModificationTime() const {
206 return toTimePoint(fs_st_mtime);
209 UniqueID file_status::getUniqueID() const {
210 return UniqueID(fs_st_dev, fs_st_ino);
213 ErrorOr<space_info> disk_space(const Twine &Path) {
215 if (::STATVFS(Path.str().c_str(), &Vfs))
216 return std::error_code(errno, std::generic_category());
217 auto FrSize = STATVFS_F_FRSIZE(Vfs);
218 space_info SpaceInfo;
219 SpaceInfo.capacity = static_cast<uint64_t>(Vfs.f_blocks) * FrSize;
220 SpaceInfo.free = static_cast<uint64_t>(Vfs.f_bfree) * FrSize;
221 SpaceInfo.available = static_cast<uint64_t>(Vfs.f_bavail) * FrSize;
225 std::error_code current_path(SmallVectorImpl<char> &result) {
228 const char *pwd = ::getenv("PWD");
229 llvm::sys::fs::file_status PWDStatus, DotStatus;
230 if (pwd && llvm::sys::path::is_absolute(pwd) &&
231 !llvm::sys::fs::status(pwd, PWDStatus) &&
232 !llvm::sys::fs::status(".", DotStatus) &&
233 PWDStatus.getUniqueID() == DotStatus.getUniqueID()) {
234 result.append(pwd, pwd + strlen(pwd));
235 return std::error_code();
239 result.reserve(MAXPATHLEN);
242 result.reserve(1024);
246 if (::getcwd(result.data(), result.capacity()) == nullptr) {
247 // See if there was a real error.
249 return std::error_code(errno, std::generic_category());
250 // Otherwise there just wasn't enough space.
251 result.reserve(result.capacity() * 2);
256 result.set_size(strlen(result.data()));
257 return std::error_code();
260 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
262 SmallString<128> path_storage;
263 StringRef p = path.toNullTerminatedStringRef(path_storage);
265 if (::mkdir(p.begin(), Perms) == -1) {
266 if (errno != EEXIST || !IgnoreExisting)
267 return std::error_code(errno, std::generic_category());
270 return std::error_code();
273 // Note that we are using symbolic link because hard links are not supported by
274 // all filesystems (SMB doesn't).
275 std::error_code create_link(const Twine &to, const Twine &from) {
277 SmallString<128> from_storage;
278 SmallString<128> to_storage;
279 StringRef f = from.toNullTerminatedStringRef(from_storage);
280 StringRef t = to.toNullTerminatedStringRef(to_storage);
282 if (::symlink(t.begin(), f.begin()) == -1)
283 return std::error_code(errno, std::generic_category());
285 return std::error_code();
288 std::error_code create_hard_link(const Twine &to, const Twine &from) {
290 SmallString<128> from_storage;
291 SmallString<128> to_storage;
292 StringRef f = from.toNullTerminatedStringRef(from_storage);
293 StringRef t = to.toNullTerminatedStringRef(to_storage);
295 if (::link(t.begin(), f.begin()) == -1)
296 return std::error_code(errno, std::generic_category());
298 return std::error_code();
301 std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
302 SmallString<128> path_storage;
303 StringRef p = path.toNullTerminatedStringRef(path_storage);
306 if (lstat(p.begin(), &buf) != 0) {
307 if (errno != ENOENT || !IgnoreNonExisting)
308 return std::error_code(errno, std::generic_category());
309 return std::error_code();
312 // Note: this check catches strange situations. In all cases, LLVM should
313 // only be involved in the creation and deletion of regular files. This
314 // check ensures that what we're trying to erase is a regular file. It
315 // effectively prevents LLVM from erasing things like /dev/null, any block
316 // special file, or other things that aren't "regular" files.
317 if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode))
318 return make_error_code(errc::operation_not_permitted);
320 if (::remove(p.begin()) == -1) {
321 if (errno != ENOENT || !IgnoreNonExisting)
322 return std::error_code(errno, std::generic_category());
325 return std::error_code();
328 std::error_code rename(const Twine &from, const Twine &to) {
330 SmallString<128> from_storage;
331 SmallString<128> to_storage;
332 StringRef f = from.toNullTerminatedStringRef(from_storage);
333 StringRef t = to.toNullTerminatedStringRef(to_storage);
335 if (::rename(f.begin(), t.begin()) == -1)
336 return std::error_code(errno, std::generic_category());
338 return std::error_code();
341 std::error_code resize_file(int FD, uint64_t Size) {
342 #if defined(HAVE_POSIX_FALLOCATE)
343 // If we have posix_fallocate use it. Unlike ftruncate it always allocates
344 // space, so we get an error if the disk is full.
345 if (int Err = ::posix_fallocate(FD, 0, Size))
346 return std::error_code(Err, std::generic_category());
348 // Use ftruncate as a fallback. It may or may not allocate space. At least on
349 // OS X with HFS+ it does.
350 if (::ftruncate(FD, Size) == -1)
351 return std::error_code(errno, std::generic_category());
354 return std::error_code();
357 static int convertAccessMode(AccessMode Mode) {
359 case AccessMode::Exist:
361 case AccessMode::Write:
363 case AccessMode::Execute:
364 return R_OK | X_OK; // scripts also need R_OK.
366 llvm_unreachable("invalid enum");
369 std::error_code access(const Twine &Path, AccessMode Mode) {
370 SmallString<128> PathStorage;
371 StringRef P = Path.toNullTerminatedStringRef(PathStorage);
373 if (::access(P.begin(), convertAccessMode(Mode)) == -1)
374 return std::error_code(errno, std::generic_category());
376 if (Mode == AccessMode::Execute) {
377 // Don't say that directories are executable.
379 if (0 != stat(P.begin(), &buf))
380 return errc::permission_denied;
381 if (!S_ISREG(buf.st_mode))
382 return errc::permission_denied;
385 return std::error_code();
388 bool can_execute(const Twine &Path) {
389 return !access(Path, AccessMode::Execute);
392 bool equivalent(file_status A, file_status B) {
393 assert(status_known(A) && status_known(B));
394 return A.fs_st_dev == B.fs_st_dev &&
395 A.fs_st_ino == B.fs_st_ino;
398 std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
399 file_status fsA, fsB;
400 if (std::error_code ec = status(A, fsA))
402 if (std::error_code ec = status(B, fsB))
404 result = equivalent(fsA, fsB);
405 return std::error_code();
408 static std::error_code fillStatus(int StatRet, const struct stat &Status,
409 file_status &Result) {
411 std::error_code ec(errno, std::generic_category());
412 if (ec == errc::no_such_file_or_directory)
413 Result = file_status(file_type::file_not_found);
415 Result = file_status(file_type::status_error);
419 file_type Type = file_type::type_unknown;
421 if (S_ISDIR(Status.st_mode))
422 Type = file_type::directory_file;
423 else if (S_ISREG(Status.st_mode))
424 Type = file_type::regular_file;
425 else if (S_ISBLK(Status.st_mode))
426 Type = file_type::block_file;
427 else if (S_ISCHR(Status.st_mode))
428 Type = file_type::character_file;
429 else if (S_ISFIFO(Status.st_mode))
430 Type = file_type::fifo_file;
431 else if (S_ISSOCK(Status.st_mode))
432 Type = file_type::socket_file;
434 perms Perms = static_cast<perms>(Status.st_mode);
436 file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_atime,
437 Status.st_mtime, Status.st_uid, Status.st_gid,
440 return std::error_code();
443 std::error_code status(const Twine &Path, file_status &Result) {
444 SmallString<128> PathStorage;
445 StringRef P = Path.toNullTerminatedStringRef(PathStorage);
448 int StatRet = ::stat(P.begin(), &Status);
449 return fillStatus(StatRet, Status, Result);
452 std::error_code status(int FD, file_status &Result) {
454 int StatRet = ::fstat(FD, &Status);
455 return fillStatus(StatRet, Status, Result);
458 std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) {
459 #if defined(HAVE_FUTIMENS)
461 Times[0] = Times[1] = sys::toTimeSpec(Time);
462 if (::futimens(FD, Times))
463 return std::error_code(errno, std::generic_category());
464 return std::error_code();
465 #elif defined(HAVE_FUTIMES)
467 Times[0] = Times[1] = sys::toTimeVal(
468 std::chrono::time_point_cast<std::chrono::microseconds>(Time));
469 if (::futimes(FD, Times))
470 return std::error_code(errno, std::generic_category());
471 return std::error_code();
473 #warning Missing futimes() and futimens()
474 return make_error_code(errc::function_not_supported);
478 std::error_code mapped_file_region::init(int FD, uint64_t Offset,
482 int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
483 int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
484 Mapping = ::mmap(nullptr, Size, prot, flags, FD, Offset);
485 if (Mapping == MAP_FAILED)
486 return std::error_code(errno, std::generic_category());
487 return std::error_code();
490 mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length,
491 uint64_t offset, std::error_code &ec)
492 : Size(length), Mapping() {
493 // Make sure that the requested size fits within SIZE_T.
494 if (length > std::numeric_limits<size_t>::max()) {
495 ec = make_error_code(errc::invalid_argument);
499 ec = init(fd, offset, mode);
504 mapped_file_region::~mapped_file_region() {
506 ::munmap(Mapping, Size);
509 uint64_t mapped_file_region::size() const {
510 assert(Mapping && "Mapping failed but used anyway!");
514 char *mapped_file_region::data() const {
515 assert(Mapping && "Mapping failed but used anyway!");
516 return reinterpret_cast<char*>(Mapping);
519 const char *mapped_file_region::const_data() const {
520 assert(Mapping && "Mapping failed but used anyway!");
521 return reinterpret_cast<const char*>(Mapping);
524 int mapped_file_region::alignment() {
525 return Process::getPageSize();
528 std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
530 SmallString<128> path_null(path);
531 DIR *directory = ::opendir(path_null.c_str());
533 return std::error_code(errno, std::generic_category());
535 it.IterationHandle = reinterpret_cast<intptr_t>(directory);
536 // Add something for replace_filename to replace.
537 path::append(path_null, ".");
538 it.CurrentEntry = directory_entry(path_null.str());
539 return directory_iterator_increment(it);
542 std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
543 if (it.IterationHandle)
544 ::closedir(reinterpret_cast<DIR *>(it.IterationHandle));
545 it.IterationHandle = 0;
546 it.CurrentEntry = directory_entry();
547 return std::error_code();
550 std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
552 dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle));
553 if (cur_dir == nullptr && errno != 0) {
554 return std::error_code(errno, std::generic_category());
555 } else if (cur_dir != nullptr) {
556 StringRef name(cur_dir->d_name, NAMLEN(cur_dir));
557 if ((name.size() == 1 && name[0] == '.') ||
558 (name.size() == 2 && name[0] == '.' && name[1] == '.'))
559 return directory_iterator_increment(it);
560 it.CurrentEntry.replace_filename(name);
562 return directory_iterator_destruct(it);
564 return std::error_code();
567 #if !defined(F_GETPATH)
568 static bool hasProcSelfFD() {
569 // If we have a /proc filesystem mounted, we can quickly establish the
570 // real name of the file with readlink
571 static const bool Result = (::access("/proc/self/fd", R_OK) == 0);
576 std::error_code openFileForRead(const Twine &Name, int &ResultFD,
577 SmallVectorImpl<char> *RealPath) {
578 SmallString<128> Storage;
579 StringRef P = Name.toNullTerminatedStringRef(Storage);
580 while ((ResultFD = open(P.begin(), O_RDONLY)) < 0) {
582 return std::error_code(errno, std::generic_category());
584 // Attempt to get the real name of the file, if the user asked
586 return std::error_code();
588 #if defined(F_GETPATH)
589 // When F_GETPATH is availble, it is the quickest way to get
590 // the real path name.
591 char Buffer[MAXPATHLEN];
592 if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1)
593 RealPath->append(Buffer, Buffer + strlen(Buffer));
595 char Buffer[PATH_MAX];
596 if (hasProcSelfFD()) {
598 snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
599 ssize_t CharCount = ::readlink(ProcPath, Buffer, sizeof(Buffer));
601 RealPath->append(Buffer, Buffer + CharCount);
603 // Use ::realpath to get the real path name
604 if (::realpath(P.begin(), Buffer) != nullptr)
605 RealPath->append(Buffer, Buffer + strlen(Buffer));
608 return std::error_code();
611 std::error_code openFileForWrite(const Twine &Name, int &ResultFD,
612 sys::fs::OpenFlags Flags, unsigned Mode) {
613 // Verify that we don't have both "append" and "excl".
614 assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
615 "Cannot specify both 'excl' and 'append' file creation flags!");
617 int OpenFlags = O_CREAT;
622 OpenFlags |= O_WRONLY;
624 if (Flags & F_Append)
625 OpenFlags |= O_APPEND;
627 OpenFlags |= O_TRUNC;
632 SmallString<128> Storage;
633 StringRef P = Name.toNullTerminatedStringRef(Storage);
634 while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) {
636 return std::error_code(errno, std::generic_category());
638 return std::error_code();
641 std::error_code getPathFromOpenFD(int FD, SmallVectorImpl<char> &ResultPath) {
643 return make_error_code(errc::bad_file_descriptor);
645 #if defined(F_GETPATH)
646 // When F_GETPATH is availble, it is the quickest way to get
647 // the path from a file descriptor.
648 ResultPath.reserve(MAXPATHLEN);
649 if (::fcntl(FD, F_GETPATH, ResultPath.begin()) == -1)
650 return std::error_code(errno, std::generic_category());
652 ResultPath.set_size(strlen(ResultPath.begin()));
654 // If we have a /proc filesystem mounted, we can quickly establish the
655 // real name of the file with readlink. Otherwise, we don't know how to
656 // get the filename from a file descriptor. Give up.
657 if (!fs::hasProcSelfFD())
658 return make_error_code(errc::function_not_supported);
660 ResultPath.reserve(PATH_MAX);
662 snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", FD);
663 ssize_t CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
665 return std::error_code(errno, std::generic_category());
667 // Was the filename truncated?
668 if (static_cast<size_t>(CharCount) == ResultPath.capacity()) {
669 // Use lstat to get the size of the filename
671 if (::lstat(ProcPath, &sb) < 0)
672 return std::error_code(errno, std::generic_category());
674 ResultPath.reserve(sb.st_size + 1);
675 CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
677 return std::error_code(errno, std::generic_category());
679 // Test for race condition: did the link size change?
680 if (CharCount > sb.st_size)
681 return std::error_code(ENAMETOOLONG, std::generic_category());
683 ResultPath.set_size(static_cast<size_t>(CharCount));
685 return std::error_code();
688 } // end namespace fs
692 bool home_directory(SmallVectorImpl<char> &result) {
693 if (char *RequestedDir = getenv("HOME")) {
695 result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
702 static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) {
703 #if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR)
704 // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR.
705 // macros defined in <unistd.h> on darwin >= 9
706 int ConfName = TempDir ? _CS_DARWIN_USER_TEMP_DIR
707 : _CS_DARWIN_USER_CACHE_DIR;
708 size_t ConfLen = confstr(ConfName, nullptr, 0);
711 Result.resize(ConfLen);
712 ConfLen = confstr(ConfName, Result.data(), Result.size());
713 } while (ConfLen > 0 && ConfLen != Result.size());
716 assert(Result.back() == 0);
727 static bool getUserCacheDir(SmallVectorImpl<char> &Result) {
728 // First try using XDG_CACHE_HOME env variable,
729 // as specified in XDG Base Directory Specification at
730 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
731 if (const char *XdgCacheDir = std::getenv("XDG_CACHE_HOME")) {
733 Result.append(XdgCacheDir, XdgCacheDir + strlen(XdgCacheDir));
737 // Try Darwin configuration query
738 if (getDarwinConfDir(false, Result))
741 // Use "$HOME/.cache" if $HOME is available
742 if (home_directory(Result)) {
743 append(Result, ".cache");
750 static const char *getEnvTempDir() {
751 // Check whether the temporary directory is specified by an environment
753 const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
754 for (const char *Env : EnvironmentVariables) {
755 if (const char *Dir = std::getenv(Env))
762 static const char *getDefaultTempDir(bool ErasedOnReboot) {
773 void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
776 if (ErasedOnReboot) {
777 // There is no env variable for the cache directory.
778 if (const char *RequestedDir = getEnvTempDir()) {
779 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
784 if (getDarwinConfDir(ErasedOnReboot, Result))
787 const char *RequestedDir = getDefaultTempDir(ErasedOnReboot);
788 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
791 } // end namespace path
793 } // end namespace sys
794 } // end namespace llvm