LLVM  7.0.0svn
Path.inc
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1 //===- llvm/Support/Unix/Path.inc - Unix Path Implementation ----*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the Unix specific implementation of the Path API.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 //===----------------------------------------------------------------------===//
15 //=== WARNING: Implementation here must contain only generic UNIX code that
16 //=== is guaranteed to work on *all* UNIX variants.
17 //===----------------------------------------------------------------------===//
18 
19 #include "Unix.h"
20 #include <limits.h>
21 #include <stdio.h>
22 #if HAVE_SYS_STAT_H
23 #include <sys/stat.h>
24 #endif
25 #if HAVE_FCNTL_H
26 #include <fcntl.h>
27 #endif
28 #ifdef HAVE_UNISTD_H
29 #include <unistd.h>
30 #endif
31 #ifdef HAVE_SYS_MMAN_H
32 #include <sys/mman.h>
33 #endif
34 
35 #include <dirent.h>
36 #include <pwd.h>
37 
38 #ifdef __APPLE__
39 #include <mach-o/dyld.h>
40 #include <sys/attr.h>
41 #endif
42 
43 // Both stdio.h and cstdio are included via different paths and
44 // stdcxx's cstdio doesn't include stdio.h, so it doesn't #undef the macros
45 // either.
46 #undef ferror
47 #undef feof
48 
49 // For GNU Hurd
50 #if defined(__GNU__) && !defined(PATH_MAX)
51 # define PATH_MAX 4096
52 #endif
53 
54 #include <sys/types.h>
55 #if !defined(__APPLE__) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && \
56  !defined(__linux__)
57 #include <sys/statvfs.h>
58 #define STATVFS statvfs
59 #define FSTATVFS fstatvfs
60 #define STATVFS_F_FRSIZE(vfs) vfs.f_frsize
61 #else
62 #if defined(__OpenBSD__) || defined(__FreeBSD__)
63 #include <sys/mount.h>
64 #include <sys/param.h>
65 #elif defined(__linux__)
66 #if defined(HAVE_LINUX_MAGIC_H)
67 #include <linux/magic.h>
68 #else
69 #if defined(HAVE_LINUX_NFS_FS_H)
70 #include <linux/nfs_fs.h>
71 #endif
72 #if defined(HAVE_LINUX_SMB_H)
73 #include <linux/smb.h>
74 #endif
75 #endif
76 #include <sys/vfs.h>
77 #else
78 #include <sys/mount.h>
79 #endif
80 #define STATVFS statfs
81 #define FSTATVFS fstatfs
82 #define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
83 #endif
84 
85 #if defined(__NetBSD__)
86 #define STATVFS_F_FLAG(vfs) (vfs).f_flag
87 #else
88 #define STATVFS_F_FLAG(vfs) (vfs).f_flags
89 #endif
90 
91 using namespace llvm;
92 
93 namespace llvm {
94 namespace sys {
95 namespace fs {
96 
97 const file_t kInvalidFile = -1;
98 
99 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
100  defined(__minix) || defined(__FreeBSD_kernel__) || defined(__linux__) || \
101  defined(__CYGWIN__) || defined(__DragonFly__) || defined(_AIX)
102 static int
103 test_dir(char ret[PATH_MAX], const char *dir, const char *bin)
104 {
105  struct stat sb;
106  char fullpath[PATH_MAX];
107 
108  snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin);
109  if (!realpath(fullpath, ret))
110  return 1;
111  if (stat(fullpath, &sb) != 0)
112  return 1;
113 
114  return 0;
115 }
116 
117 static char *
118 getprogpath(char ret[PATH_MAX], const char *bin)
119 {
120  char *pv, *s, *t;
121 
122  /* First approach: absolute path. */
123  if (bin[0] == '/') {
124  if (test_dir(ret, "/", bin) == 0)
125  return ret;
126  return nullptr;
127  }
128 
129  /* Second approach: relative path. */
130  if (strchr(bin, '/')) {
131  char cwd[PATH_MAX];
132  if (!getcwd(cwd, PATH_MAX))
133  return nullptr;
134  if (test_dir(ret, cwd, bin) == 0)
135  return ret;
136  return nullptr;
137  }
138 
139  /* Third approach: $PATH */
140  if ((pv = getenv("PATH")) == nullptr)
141  return nullptr;
142  s = pv = strdup(pv);
143  if (!pv)
144  return nullptr;
145  while ((t = strsep(&s, ":")) != nullptr) {
146  if (test_dir(ret, t, bin) == 0) {
147  free(pv);
148  return ret;
149  }
150  }
151  free(pv);
152  return nullptr;
153 }
154 #endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
155 
156 /// GetMainExecutable - Return the path to the main executable, given the
157 /// value of argv[0] from program startup.
158 std::string getMainExecutable(const char *argv0, void *MainAddr) {
159 #if defined(__APPLE__)
160  // On OS X the executable path is saved to the stack by dyld. Reading it
161  // from there is much faster than calling dladdr, especially for large
162  // binaries with symbols.
163  char exe_path[MAXPATHLEN];
164  uint32_t size = sizeof(exe_path);
165  if (_NSGetExecutablePath(exe_path, &size) == 0) {
166  char link_path[MAXPATHLEN];
167  if (realpath(exe_path, link_path))
168  return link_path;
169  }
170 #elif defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
171  defined(__minix) || defined(__DragonFly__) || \
172  defined(__FreeBSD_kernel__) || defined(_AIX)
173  char exe_path[PATH_MAX];
174 
175  if (getprogpath(exe_path, argv0) != NULL)
176  return exe_path;
177 #elif defined(__linux__) || defined(__CYGWIN__)
178  char exe_path[MAXPATHLEN];
179  StringRef aPath("/proc/self/exe");
180  if (sys::fs::exists(aPath)) {
181  // /proc is not always mounted under Linux (chroot for example).
182  ssize_t len = readlink(aPath.str().c_str(), exe_path, sizeof(exe_path));
183  if (len >= 0)
184  return std::string(exe_path, len);
185  } else {
186  // Fall back to the classical detection.
187  if (getprogpath(exe_path, argv0))
188  return exe_path;
189  }
190 #elif defined(HAVE_DLFCN_H) && defined(HAVE_DLADDR)
191  // Use dladdr to get executable path if available.
192  Dl_info DLInfo;
193  int err = dladdr(MainAddr, &DLInfo);
194  if (err == 0)
195  return "";
196 
197  // If the filename is a symlink, we need to resolve and return the location of
198  // the actual executable.
199  char link_path[MAXPATHLEN];
200  if (realpath(DLInfo.dli_fname, link_path))
201  return link_path;
202 #else
203 #error GetMainExecutable is not implemented on this host yet.
204 #endif
205  return "";
206 }
207 
208 TimePoint<> basic_file_status::getLastAccessedTime() const {
209  return toTimePoint(fs_st_atime);
210 }
211 
212 TimePoint<> basic_file_status::getLastModificationTime() const {
213  return toTimePoint(fs_st_mtime);
214 }
215 
216 UniqueID file_status::getUniqueID() const {
217  return UniqueID(fs_st_dev, fs_st_ino);
218 }
219 
221  return fs_st_nlinks;
222 }
223 
224 ErrorOr<space_info> disk_space(const Twine &Path) {
225  struct STATVFS Vfs;
226  if (::STATVFS(Path.str().c_str(), &Vfs))
227  return std::error_code(errno, std::generic_category());
228  auto FrSize = STATVFS_F_FRSIZE(Vfs);
229  space_info SpaceInfo;
230  SpaceInfo.capacity = static_cast<uint64_t>(Vfs.f_blocks) * FrSize;
231  SpaceInfo.free = static_cast<uint64_t>(Vfs.f_bfree) * FrSize;
232  SpaceInfo.available = static_cast<uint64_t>(Vfs.f_bavail) * FrSize;
233  return SpaceInfo;
234 }
235 
236 std::error_code current_path(SmallVectorImpl<char> &result) {
237  result.clear();
238 
239  const char *pwd = ::getenv("PWD");
240  llvm::sys::fs::file_status PWDStatus, DotStatus;
241  if (pwd && llvm::sys::path::is_absolute(pwd) &&
242  !llvm::sys::fs::status(pwd, PWDStatus) &&
243  !llvm::sys::fs::status(".", DotStatus) &&
244  PWDStatus.getUniqueID() == DotStatus.getUniqueID()) {
245  result.append(pwd, pwd + strlen(pwd));
246  return std::error_code();
247  }
248 
249 #ifdef MAXPATHLEN
250  result.reserve(MAXPATHLEN);
251 #else
252 // For GNU Hurd
253  result.reserve(1024);
254 #endif
255 
256  while (true) {
257  if (::getcwd(result.data(), result.capacity()) == nullptr) {
258  // See if there was a real error.
259  if (errno != ENOMEM)
260  return std::error_code(errno, std::generic_category());
261  // Otherwise there just wasn't enough space.
262  result.reserve(result.capacity() * 2);
263  } else
264  break;
265  }
266 
267  result.set_size(strlen(result.data()));
268  return std::error_code();
269 }
270 
271 std::error_code set_current_path(const Twine &path) {
272  SmallString<128> path_storage;
273  StringRef p = path.toNullTerminatedStringRef(path_storage);
274 
275  if (::chdir(p.begin()) == -1)
276  return std::error_code(errno, std::generic_category());
277 
278  return std::error_code();
279 }
280 
281 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
282  perms Perms) {
283  SmallString<128> path_storage;
284  StringRef p = path.toNullTerminatedStringRef(path_storage);
285 
286  if (::mkdir(p.begin(), Perms) == -1) {
287  if (errno != EEXIST || !IgnoreExisting)
288  return std::error_code(errno, std::generic_category());
289  }
290 
291  return std::error_code();
292 }
293 
294 // Note that we are using symbolic link because hard links are not supported by
295 // all filesystems (SMB doesn't).
296 std::error_code create_link(const Twine &to, const Twine &from) {
297  // Get arguments.
298  SmallString<128> from_storage;
299  SmallString<128> to_storage;
300  StringRef f = from.toNullTerminatedStringRef(from_storage);
301  StringRef t = to.toNullTerminatedStringRef(to_storage);
302 
303  if (::symlink(t.begin(), f.begin()) == -1)
304  return std::error_code(errno, std::generic_category());
305 
306  return std::error_code();
307 }
308 
309 std::error_code create_hard_link(const Twine &to, const Twine &from) {
310  // Get arguments.
311  SmallString<128> from_storage;
312  SmallString<128> to_storage;
313  StringRef f = from.toNullTerminatedStringRef(from_storage);
314  StringRef t = to.toNullTerminatedStringRef(to_storage);
315 
316  if (::link(t.begin(), f.begin()) == -1)
317  return std::error_code(errno, std::generic_category());
318 
319  return std::error_code();
320 }
321 
322 std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
323  SmallString<128> path_storage;
324  StringRef p = path.toNullTerminatedStringRef(path_storage);
325 
326  struct stat buf;
327  if (lstat(p.begin(), &buf) != 0) {
328  if (errno != ENOENT || !IgnoreNonExisting)
329  return std::error_code(errno, std::generic_category());
330  return std::error_code();
331  }
332 
333  // Note: this check catches strange situations. In all cases, LLVM should
334  // only be involved in the creation and deletion of regular files. This
335  // check ensures that what we're trying to erase is a regular file. It
336  // effectively prevents LLVM from erasing things like /dev/null, any block
337  // special file, or other things that aren't "regular" files.
338  if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode))
340 
341  if (::remove(p.begin()) == -1) {
342  if (errno != ENOENT || !IgnoreNonExisting)
343  return std::error_code(errno, std::generic_category());
344  }
345 
346  return std::error_code();
347 }
348 
349 static bool is_local_impl(struct STATVFS &Vfs) {
350 #if defined(__linux__)
351 #ifndef NFS_SUPER_MAGIC
352 #define NFS_SUPER_MAGIC 0x6969
353 #endif
354 #ifndef SMB_SUPER_MAGIC
355 #define SMB_SUPER_MAGIC 0x517B
356 #endif
357 #ifndef CIFS_MAGIC_NUMBER
358 #define CIFS_MAGIC_NUMBER 0xFF534D42
359 #endif
360  switch ((uint32_t)Vfs.f_type) {
361  case NFS_SUPER_MAGIC:
362  case SMB_SUPER_MAGIC:
363  case CIFS_MAGIC_NUMBER:
364  return false;
365  default:
366  return true;
367  }
368 #elif defined(__CYGWIN__)
369  // Cygwin doesn't expose this information; would need to use Win32 API.
370  return false;
371 #elif defined(__Fuchsia__)
372  // Fuchsia doesn't yet support remote filesystem mounts.
373  return true;
374 #elif defined(__HAIKU__)
375  // Haiku doesn't expose this information.
376  return false;
377 #elif defined(__sun)
378  // statvfs::f_basetype contains a null-terminated FSType name of the mounted target
379  StringRef fstype(Vfs.f_basetype);
380  // NFS is the only non-local fstype??
381  return !fstype.equals("nfs");
382 #else
383  return !!(STATVFS_F_FLAG(Vfs) & MNT_LOCAL);
384 #endif
385 }
386 
387 std::error_code is_local(const Twine &Path, bool &Result) {
388  struct STATVFS Vfs;
389  if (::STATVFS(Path.str().c_str(), &Vfs))
390  return std::error_code(errno, std::generic_category());
391 
392  Result = is_local_impl(Vfs);
393  return std::error_code();
394 }
395 
396 std::error_code is_local(int FD, bool &Result) {
397  struct STATVFS Vfs;
398  if (::FSTATVFS(FD, &Vfs))
399  return std::error_code(errno, std::generic_category());
400 
401  Result = is_local_impl(Vfs);
402  return std::error_code();
403 }
404 
405 std::error_code rename(const Twine &from, const Twine &to) {
406  // Get arguments.
407  SmallString<128> from_storage;
408  SmallString<128> to_storage;
409  StringRef f = from.toNullTerminatedStringRef(from_storage);
410  StringRef t = to.toNullTerminatedStringRef(to_storage);
411 
412  if (::rename(f.begin(), t.begin()) == -1)
413  return std::error_code(errno, std::generic_category());
414 
415  return std::error_code();
416 }
417 
418 std::error_code resize_file(int FD, uint64_t Size) {
419 #if defined(HAVE_POSIX_FALLOCATE)
420  // If we have posix_fallocate use it. Unlike ftruncate it always allocates
421  // space, so we get an error if the disk is full.
422  if (int Err = ::posix_fallocate(FD, 0, Size)) {
423  if (Err != EINVAL && Err != EOPNOTSUPP)
424  return std::error_code(Err, std::generic_category());
425  }
426 #endif
427  // Use ftruncate as a fallback. It may or may not allocate space. At least on
428  // OS X with HFS+ it does.
429  if (::ftruncate(FD, Size) == -1)
430  return std::error_code(errno, std::generic_category());
431 
432  return std::error_code();
433 }
434 
435 static int convertAccessMode(AccessMode Mode) {
436  switch (Mode) {
437  case AccessMode::Exist:
438  return F_OK;
439  case AccessMode::Write:
440  return W_OK;
441  case AccessMode::Execute:
442  return R_OK | X_OK; // scripts also need R_OK.
443  }
444  llvm_unreachable("invalid enum");
445 }
446 
447 std::error_code access(const Twine &Path, AccessMode Mode) {
448  SmallString<128> PathStorage;
449  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
450 
451  if (::access(P.begin(), convertAccessMode(Mode)) == -1)
452  return std::error_code(errno, std::generic_category());
453 
454  if (Mode == AccessMode::Execute) {
455  // Don't say that directories are executable.
456  struct stat buf;
457  if (0 != stat(P.begin(), &buf))
459  if (!S_ISREG(buf.st_mode))
461  }
462 
463  return std::error_code();
464 }
465 
466 bool can_execute(const Twine &Path) {
467  return !access(Path, AccessMode::Execute);
468 }
469 
470 bool equivalent(file_status A, file_status B) {
471  assert(status_known(A) && status_known(B));
472  return A.fs_st_dev == B.fs_st_dev &&
473  A.fs_st_ino == B.fs_st_ino;
474 }
475 
476 std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
477  file_status fsA, fsB;
478  if (std::error_code ec = status(A, fsA))
479  return ec;
480  if (std::error_code ec = status(B, fsB))
481  return ec;
482  result = equivalent(fsA, fsB);
483  return std::error_code();
484 }
485 
486 static void expandTildeExpr(SmallVectorImpl<char> &Path) {
487  StringRef PathStr(Path.begin(), Path.size());
488  if (PathStr.empty() || !PathStr.startswith("~"))
489  return;
490 
491  PathStr = PathStr.drop_front();
492  StringRef Expr =
493  PathStr.take_until([](char c) { return path::is_separator(c); });
494  StringRef Remainder = PathStr.substr(Expr.size() + 1);
495  SmallString<128> Storage;
496  if (Expr.empty()) {
497  // This is just ~/..., resolve it to the current user's home dir.
498  if (!path::home_directory(Storage)) {
499  // For some reason we couldn't get the home directory. Just exit.
500  return;
501  }
502 
503  // Overwrite the first character and insert the rest.
504  Path[0] = Storage[0];
505  Path.insert(Path.begin() + 1, Storage.begin() + 1, Storage.end());
506  return;
507  }
508 
509  // This is a string of the form ~username/, look up this user's entry in the
510  // password database.
511  struct passwd *Entry = nullptr;
512  std::string User = Expr.str();
513  Entry = ::getpwnam(User.c_str());
514 
515  if (!Entry) {
516  // Unable to look up the entry, just return back the original path.
517  return;
518  }
519 
520  Storage = Remainder;
521  Path.clear();
522  Path.append(Entry->pw_dir, Entry->pw_dir + strlen(Entry->pw_dir));
523  llvm::sys::path::append(Path, Storage);
524 }
525 
526 static std::error_code fillStatus(int StatRet, const struct stat &Status,
527  file_status &Result) {
528  if (StatRet != 0) {
529  std::error_code ec(errno, std::generic_category());
531  Result = file_status(file_type::file_not_found);
532  else
533  Result = file_status(file_type::status_error);
534  return ec;
535  }
536 
538 
539  if (S_ISDIR(Status.st_mode))
541  else if (S_ISREG(Status.st_mode))
543  else if (S_ISBLK(Status.st_mode))
544  Type = file_type::block_file;
545  else if (S_ISCHR(Status.st_mode))
547  else if (S_ISFIFO(Status.st_mode))
548  Type = file_type::fifo_file;
549  else if (S_ISSOCK(Status.st_mode))
550  Type = file_type::socket_file;
551  else if (S_ISLNK(Status.st_mode))
553 
554  perms Perms = static_cast<perms>(Status.st_mode) & all_perms;
555  Result = file_status(Type, Perms, Status.st_dev, Status.st_nlink,
556  Status.st_ino, Status.st_atime, Status.st_mtime,
557  Status.st_uid, Status.st_gid, Status.st_size);
558 
559  return std::error_code();
560 }
561 
562 std::error_code status(const Twine &Path, file_status &Result, bool Follow) {
563  SmallString<128> PathStorage;
564  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
565 
566  struct stat Status;
567  int StatRet = (Follow ? ::stat : ::lstat)(P.begin(), &Status);
568  return fillStatus(StatRet, Status, Result);
569 }
570 
571 std::error_code status(int FD, file_status &Result) {
572  struct stat Status;
573  int StatRet = ::fstat(FD, &Status);
574  return fillStatus(StatRet, Status, Result);
575 }
576 
577 std::error_code setPermissions(const Twine &Path, perms Permissions) {
578  SmallString<128> PathStorage;
579  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
580 
581  if (::chmod(P.begin(), Permissions))
582  return std::error_code(errno, std::generic_category());
583  return std::error_code();
584 }
585 
586 std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) {
587 #if defined(HAVE_FUTIMENS)
588  timespec Times[2];
589  Times[0] = Times[1] = sys::toTimeSpec(Time);
590  if (::futimens(FD, Times))
591  return std::error_code(errno, std::generic_category());
592  return std::error_code();
593 #elif defined(HAVE_FUTIMES)
594  timeval Times[2];
595  Times[0] = Times[1] = sys::toTimeVal(
596  std::chrono::time_point_cast<std::chrono::microseconds>(Time));
597  if (::futimes(FD, Times))
598  return std::error_code(errno, std::generic_category());
599  return std::error_code();
600 #else
601 #warning Missing futimes() and futimens()
603 #endif
604 }
605 
606 std::error_code mapped_file_region::init(int FD, uint64_t Offset,
607  mapmode Mode) {
608  assert(Size != 0);
609 
610  int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
611  int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
612 #if defined(__APPLE__)
613  //----------------------------------------------------------------------
614  // Newer versions of MacOSX have a flag that will allow us to read from
615  // binaries whose code signature is invalid without crashing by using
616  // the MAP_RESILIENT_CODESIGN flag. Also if a file from removable media
617  // is mapped we can avoid crashing and return zeroes to any pages we try
618  // to read if the media becomes unavailable by using the
619  // MAP_RESILIENT_MEDIA flag. These flags are only usable when mapping
620  // with PROT_READ, so take care not to specify them otherwise.
621  //----------------------------------------------------------------------
622  if (Mode == readonly) {
623 #if defined(MAP_RESILIENT_CODESIGN)
624  flags |= MAP_RESILIENT_CODESIGN;
625 #endif
626 #if defined(MAP_RESILIENT_MEDIA)
627  flags |= MAP_RESILIENT_MEDIA;
628 #endif
629  }
630 #endif // #if defined (__APPLE__)
631 
632  Mapping = ::mmap(nullptr, Size, prot, flags, FD, Offset);
633  if (Mapping == MAP_FAILED)
634  return std::error_code(errno, std::generic_category());
635  return std::error_code();
636 }
637 
638 mapped_file_region::mapped_file_region(int fd, mapmode mode, size_t length,
639  uint64_t offset, std::error_code &ec)
640  : Size(length), Mapping(), Mode(mode) {
641  (void)Mode;
642  ec = init(fd, offset, mode);
643  if (ec)
644  Mapping = nullptr;
645 }
646 
647 mapped_file_region::~mapped_file_region() {
648  if (Mapping)
649  ::munmap(Mapping, Size);
650 }
651 
652 size_t mapped_file_region::size() const {
653  assert(Mapping && "Mapping failed but used anyway!");
654  return Size;
655 }
656 
657 char *mapped_file_region::data() const {
658  assert(Mapping && "Mapping failed but used anyway!");
659  return reinterpret_cast<char*>(Mapping);
660 }
661 
662 const char *mapped_file_region::const_data() const {
663  assert(Mapping && "Mapping failed but used anyway!");
664  return reinterpret_cast<const char*>(Mapping);
665 }
666 
667 int mapped_file_region::alignment() {
668  return Process::getPageSize();
669 }
670 
671 std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
672  StringRef path,
673  bool follow_symlinks) {
674  SmallString<128> path_null(path);
675  DIR *directory = ::opendir(path_null.c_str());
676  if (!directory)
677  return std::error_code(errno, std::generic_category());
678 
679  it.IterationHandle = reinterpret_cast<intptr_t>(directory);
680  // Add something for replace_filename to replace.
681  path::append(path_null, ".");
682  it.CurrentEntry = directory_entry(path_null.str(), follow_symlinks);
683  return directory_iterator_increment(it);
684 }
685 
686 std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
687  if (it.IterationHandle)
688  ::closedir(reinterpret_cast<DIR *>(it.IterationHandle));
689  it.IterationHandle = 0;
690  it.CurrentEntry = directory_entry();
691  return std::error_code();
692 }
693 
694 std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
695  errno = 0;
696  dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle));
697  if (cur_dir == nullptr && errno != 0) {
698  return std::error_code(errno, std::generic_category());
699  } else if (cur_dir != nullptr) {
700  StringRef name(cur_dir->d_name);
701  if ((name.size() == 1 && name[0] == '.') ||
702  (name.size() == 2 && name[0] == '.' && name[1] == '.'))
703  return directory_iterator_increment(it);
704  it.CurrentEntry.replace_filename(name);
705  } else
706  return directory_iterator_destruct(it);
707 
708  return std::error_code();
709 }
710 
712  file_status s;
713  if (auto EC = fs::status(Path, s, FollowSymlinks))
714  return EC;
715  return s;
716 }
717 
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);
723  return Result;
724 }
725 #endif
726 
727 static int nativeOpenFlags(CreationDisposition Disp, OpenFlags Flags,
728  FileAccess Access) {
729  int Result = 0;
730  if (Access == FA_Read)
731  Result |= O_RDONLY;
732  else if (Access == FA_Write)
733  Result |= O_WRONLY;
734  else if (Access == (FA_Read | FA_Write))
735  Result |= O_RDWR;
736 
737  // This is for compatibility with old code that assumed F_Append implied
738  // would open an existing file. See Windows/Path.inc for a longer comment.
739  if (Flags & F_Append)
740  Disp = CD_OpenAlways;
741 
742  if (Disp == CD_CreateNew) {
743  Result |= O_CREAT; // Create if it doesn't exist.
744  Result |= O_EXCL; // Fail if it does.
745  } else if (Disp == CD_CreateAlways) {
746  Result |= O_CREAT; // Create if it doesn't exist.
747  Result |= O_TRUNC; // Truncate if it does.
748  } else if (Disp == CD_OpenAlways) {
749  Result |= O_CREAT; // Create if it doesn't exist.
750  } else if (Disp == CD_OpenExisting) {
751  // Nothing special, just don't add O_CREAT and we get these semantics.
752  }
753 
754  if (Flags & F_Append)
755  Result |= O_APPEND;
756 
757 #ifdef O_CLOEXEC
758  if (!(Flags & OF_ChildInherit))
759  Result |= O_CLOEXEC;
760 #endif
761 
762  return Result;
763 }
764 
765 std::error_code openFile(const Twine &Name, int &ResultFD,
766  CreationDisposition Disp, FileAccess Access,
767  OpenFlags Flags, unsigned Mode) {
768  int OpenFlags = nativeOpenFlags(Disp, Flags, Access);
769 
770  SmallString<128> Storage;
771  StringRef P = Name.toNullTerminatedStringRef(Storage);
772  if ((ResultFD = sys::RetryAfterSignal(-1, ::open, P.begin(), OpenFlags, Mode)) <
773  0)
774  return std::error_code(errno, std::generic_category());
775 #ifndef O_CLOEXEC
776  if (!(Flags & OF_ChildInherit)) {
777  int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC);
778  (void)r;
779  assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed");
780  }
781 #endif
782  return std::error_code();
783 }
784 
786  FileAccess Access, OpenFlags Flags,
787  unsigned Mode) {
788 
789  int FD;
790  std::error_code EC = openFile(Name, FD, Disp, Access, Flags, Mode);
791  if (EC)
792  return errorCodeToError(EC);
793  return FD;
794 }
795 
796 std::error_code openFileForRead(const Twine &Name, int &ResultFD,
797  OpenFlags Flags,
798  SmallVectorImpl<char> *RealPath) {
799  std::error_code EC =
800  openFile(Name, ResultFD, CD_OpenExisting, FA_Read, Flags, 0666);
801  if (EC)
802  return EC;
803 
804  // Attempt to get the real name of the file, if the user asked
805  if(!RealPath)
806  return std::error_code();
807  RealPath->clear();
808 #if defined(F_GETPATH)
809  // When F_GETPATH is availble, it is the quickest way to get
810  // the real path name.
811  char Buffer[MAXPATHLEN];
812  if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1)
813  RealPath->append(Buffer, Buffer + strlen(Buffer));
814 #else
815  char Buffer[PATH_MAX];
816  if (hasProcSelfFD()) {
817  char ProcPath[64];
818  snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
819  ssize_t CharCount = ::readlink(ProcPath, Buffer, sizeof(Buffer));
820  if (CharCount > 0)
821  RealPath->append(Buffer, Buffer + CharCount);
822  } else {
823  SmallString<128> Storage;
824  StringRef P = Name.toNullTerminatedStringRef(Storage);
825 
826  // Use ::realpath to get the real path name
827  if (::realpath(P.begin(), Buffer) != nullptr)
828  RealPath->append(Buffer, Buffer + strlen(Buffer));
829  }
830 #endif
831  return std::error_code();
832 }
833 
834 Expected<file_t> openNativeFileForRead(const Twine &Name, OpenFlags Flags,
835  SmallVectorImpl<char> *RealPath) {
836  file_t ResultFD;
837  std::error_code EC = openFileForRead(Name, ResultFD, Flags, RealPath);
838  if (EC)
839  return errorCodeToError(EC);
840  return ResultFD;
841 }
842 
843 void closeFile(file_t &F) {
844  ::close(F);
845  F = kInvalidFile;
846 }
847 
848 template <typename T>
849 static std::error_code remove_directories_impl(const T &Entry,
850  bool IgnoreErrors) {
851  std::error_code EC;
852  directory_iterator Begin(Entry, EC, false);
853  directory_iterator End;
854  while (Begin != End) {
855  auto &Item = *Begin;
856  ErrorOr<basic_file_status> st = Item.status();
857  if (!st && !IgnoreErrors)
858  return st.getError();
859 
860  if (is_directory(*st)) {
861  EC = remove_directories_impl(Item, IgnoreErrors);
862  if (EC && !IgnoreErrors)
863  return EC;
864  }
865 
866  EC = fs::remove(Item.path(), true);
867  if (EC && !IgnoreErrors)
868  return EC;
869 
870  Begin.increment(EC);
871  if (EC && !IgnoreErrors)
872  return EC;
873  }
874  return std::error_code();
875 }
876 
877 std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
878  auto EC = remove_directories_impl(path, IgnoreErrors);
879  if (EC && !IgnoreErrors)
880  return EC;
881  EC = fs::remove(path, true);
882  if (EC && !IgnoreErrors)
883  return EC;
884  return std::error_code();
885 }
886 
887 std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,
888  bool expand_tilde) {
889  dest.clear();
890  if (path.isTriviallyEmpty())
891  return std::error_code();
892 
893  if (expand_tilde) {
894  SmallString<128> Storage;
895  path.toVector(Storage);
896  expandTildeExpr(Storage);
897  return real_path(Storage, dest, false);
898  }
899 
900  SmallString<128> Storage;
901  StringRef P = path.toNullTerminatedStringRef(Storage);
902  char Buffer[PATH_MAX];
903  if (::realpath(P.begin(), Buffer) == nullptr)
904  return std::error_code(errno, std::generic_category());
905  dest.append(Buffer, Buffer + strlen(Buffer));
906  return std::error_code();
907 }
908 
909 } // end namespace fs
910 
911 namespace path {
912 
914  char *RequestedDir = getenv("HOME");
915  if (!RequestedDir) {
916  struct passwd *pw = getpwuid(getuid());
917  if (pw && pw->pw_dir)
918  RequestedDir = pw->pw_dir;
919  }
920  if (!RequestedDir)
921  return false;
922 
923  result.clear();
924  result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
925  return true;
926 }
927 
928 static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) {
929  #if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR)
930  // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR.
931  // macros defined in <unistd.h> on darwin >= 9
932  int ConfName = TempDir ? _CS_DARWIN_USER_TEMP_DIR
933  : _CS_DARWIN_USER_CACHE_DIR;
934  size_t ConfLen = confstr(ConfName, nullptr, 0);
935  if (ConfLen > 0) {
936  do {
937  Result.resize(ConfLen);
938  ConfLen = confstr(ConfName, Result.data(), Result.size());
939  } while (ConfLen > 0 && ConfLen != Result.size());
940 
941  if (ConfLen > 0) {
942  assert(Result.back() == 0);
943  Result.pop_back();
944  return true;
945  }
946 
947  Result.clear();
948  }
949  #endif
950  return false;
951 }
952 
953 static bool getUserCacheDir(SmallVectorImpl<char> &Result) {
954  // First try using XDG_CACHE_HOME env variable,
955  // as specified in XDG Base Directory Specification at
956  // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
957  if (const char *XdgCacheDir = std::getenv("XDG_CACHE_HOME")) {
958  Result.clear();
959  Result.append(XdgCacheDir, XdgCacheDir + strlen(XdgCacheDir));
960  return true;
961  }
962 
963  // Try Darwin configuration query
964  if (getDarwinConfDir(false, Result))
965  return true;
966 
967  // Use "$HOME/.cache" if $HOME is available
968  if (home_directory(Result)) {
969  append(Result, ".cache");
970  return true;
971  }
972 
973  return false;
974 }
975 
976 static const char *getEnvTempDir() {
977  // Check whether the temporary directory is specified by an environment
978  // variable.
979  const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
980  for (const char *Env : EnvironmentVariables) {
981  if (const char *Dir = std::getenv(Env))
982  return Dir;
983  }
984 
985  return nullptr;
986 }
987 
988 static const char *getDefaultTempDir(bool ErasedOnReboot) {
989 #ifdef P_tmpdir
990  if ((bool)P_tmpdir)
991  return P_tmpdir;
992 #endif
993 
994  if (ErasedOnReboot)
995  return "/tmp";
996  return "/var/tmp";
997 }
998 
999 void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
1000  Result.clear();
1001 
1002  if (ErasedOnReboot) {
1003  // There is no env variable for the cache directory.
1004  if (const char *RequestedDir = getEnvTempDir()) {
1005  Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
1006  return;
1007  }
1008  }
1009 
1010  if (getDarwinConfDir(ErasedOnReboot, Result))
1011  return;
1012 
1013  const char *RequestedDir = getDefaultTempDir(ErasedOnReboot);
1014  Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
1015 }
1016 
1017 } // end namespace path
1018 
1019 } // end namespace sys
1020 } // end namespace llvm
const file_t kInvalidFile
bool is_separator(char value, Style style=Style::native)
Check whether the given char is a path separator on the host OS.
Definition: Path.cpp:609
bool can_execute(const Twine &Path)
Can we execute this file?
Represents either an error or a value T.
Definition: ErrorOr.h:69
LLVM_NODISCARD std::string str() const
str - Get the contents as an std::string.
Definition: StringRef.h:228
SI Whole Quad Mode
bool status_known(const basic_file_status &s)
Is status available?
Definition: Path.cpp:1018
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
std::error_code openFileForRead(const Twine &Name, int &ResultFD, OpenFlags Flags=OF_None, SmallVectorImpl< char > *RealPath=nullptr)
Opens the file with the given name in a read-only mode, returning its open file descriptor.
void closeFile(file_t &F)
Close the file object.
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:137
std::error_code remove(const Twine &path, bool IgnoreNonExisting=true)
Remove path.
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE size_t size() const
size - Get the string size.
Definition: StringRef.h:138
bool isTriviallyEmpty() const
Check if this twine is trivially empty; a false return value does not necessarily mean the twine is e...
Definition: Twine.h:398
std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time)
Set the file modification and access time.
std::error_code current_path(SmallVectorImpl< char > &result)
Get the current path.
bool is_directory(const basic_file_status &status)
Does status represent a directory?
Definition: Path.cpp:1029
Expected< file_t > openNativeFile(const Twine &Name, CreationDisposition Disp, FileAccess Access, OpenFlags Flags, unsigned Mode=0666)
Opens a file with the specified creation disposition, access mode, and flags and returns a platform-s...
F(f)
void reserve(size_type N)
Definition: SmallVector.h:377
std::error_code remove_directories(const Twine &path, bool IgnoreErrors=true)
Recursively delete a directory.
Represents the result of a call to sys::fs::status().
Definition: FileSystem.h:229
LLVM_ATTRIBUTE_ALWAYS_INLINE TimePoint< std::chrono::seconds > toTimePoint(std::time_t T)
Convert a std::time_t to a TimePoint.
Definition: Chrono.h:45
CD_OpenAlways - When opening a file:
Definition: FileSystem.h:699
struct timespec toTimeSpec(TimePoint<> TP)
Convert a time point to struct timespec.
Definition: Unix.h:84
amode Optimize addressing mode
std::error_code directory_iterator_increment(DirIterState &)
void append(SmallVectorImpl< char > &path, const Twine &a, const Twine &b="", const Twine &c="", const Twine &d="")
Append to path.
Definition: Path.cpp:471
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
std::error_code make_error_code(BitcodeError E)
bool is_absolute(const Twine &path, Style style=Style::native)
Is path absolute?
Definition: Path.cpp:679
Tagged union holding either a T or a Error.
Definition: CachePruning.h:23
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef take_until(function_ref< bool(char)> F) const
Return the longest prefix of &#39;this&#39; such that no character in the prefix satisfies the given predicat...
Definition: StringRef.h:637
When a child process is launched, this file should remain open in the child process.
Definition: FileSystem.h:730
CD_CreateNew - When opening a file:
Definition: FileSystem.h:694
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:133
std::error_code is_local(const Twine &path, bool &result)
Is the file mounted on a local filesystem?
std::error_code create_link(const Twine &to, const Twine &from)
Create a link from from to to.
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef substr(size_t Start, size_t N=npos) const
Return a reference to the substring from [Start, Start + N).
Definition: StringRef.h:598
std::string getMainExecutable(const char *argv0, void *MainExecAddr)
Return the path to the main executable, given the value of argv[0] from program startup and the addre...
std::error_code real_path(const Twine &path, SmallVectorImpl< char > &output, bool expand_tilde=false)
Collapse all .
#define P(N)
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:410
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
size_t capacity() const
Return the total number of elements in the currently allocated buffer.
Definition: SmallVector.h:141
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:46
std::error_code status(const Twine &path, file_status &result, bool follow=true)
Get file status as if by POSIX stat().
UniqueID getUniqueID() const
Error errorCodeToError(std::error_code EC)
Helper for converting an std::error_code to a Error.
Definition: Error.cpp:78
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:117
std::error_code getError() const
Definition: ErrorOr.h:172
uint32_t getLinkCount() const
TimePoint getLastModificationTime() const
StringRef toNullTerminatedStringRef(SmallVectorImpl< char > &Out) const
This returns the twine as a single null terminated StringRef if it can be represented as such...
Definition: Twine.cpp:38
std::error_code resize_file(int FD, uint64_t Size)
Resize path to size.
auto RetryAfterSignal(const FailT &Fail, const Fun &F, const Args &... As) -> decltype(F(As...))
Definition: Errno.h:34
struct timeval toTimeVal(TimePoint< std::chrono::microseconds > TP)
Convert a time point to struct timeval.
Definition: Unix.h:94
std::error_code create_hard_link(const Twine &to, const Twine &from)
Create a hard link from from to to, or return an error.
void toVector(SmallVectorImpl< char > &Out) const
Append the concatenated string into the given SmallString or SmallVector.
Definition: Twine.cpp:33
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
static unsigned getPageSize()
std::error_code rename(const Twine &from, const Twine &to)
Rename from to to.
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef drop_front(size_t N=1) const
Return a StringRef equal to &#39;this&#39; but with the first N elements dropped.
Definition: StringRef.h:645
auto size(R &&Range, typename std::enable_if< std::is_same< typename std::iterator_traits< decltype(Range.begin())>::iterator_category, std::random_access_iterator_tag >::value, void >::type *=nullptr) -> decltype(std::distance(Range.begin(), Range.end()))
Get the size of a range.
Definition: STLExtras.h:1032
std::error_code directory_iterator_construct(DirIterState &, StringRef, bool)
Expected< file_t > openNativeFileForRead(const Twine &Name, OpenFlags Flags=OF_None, SmallVectorImpl< char > *RealPath=nullptr)
Opens the file with the given name in a read-only mode, returning its open file descriptor.
std::error_code setPermissions(const Twine &Path, perms Permissions)
Set file permissions.
iterator insert(iterator I, T &&Elt)
Definition: SmallVector.h:479
std::error_code set_current_path(const Twine &path)
Set the current path.
iterator begin() const
Definition: StringRef.h:106
void append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:395
ErrorOr< space_info > disk_space(const Twine &Path)
Get disk space usage information.
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:121
void set_size(size_type N)
Set the array size to N, which the current array must have enough capacity for.
Definition: SmallVector.h:686
std::error_code directory_iterator_destruct(DirIterState &)
pointer data()
Return a pointer to the vector&#39;s buffer, even if empty().
Definition: SmallVector.h:144
file_type
An enumeration for the file system&#39;s view of the type.
Definition: FileSystem.h:67
static GCRegistry::Add< ErlangGC > A("erlang", "erlang-compatible garbage collector")
std::error_code create_directory(const Twine &path, bool IgnoreExisting=true, perms Perms=owner_all|group_all)
Create the directory in path.
static std::unique_ptr< MemoryBuffer > openFile(const Twine &Path)
std::string str() const
Return the twine contents as a std::string.
Definition: Twine.cpp:18
void system_temp_directory(bool erasedOnReboot, SmallVectorImpl< char > &result)
Get the typical temporary directory for the system, e.g., "/var/tmp" or "C:/TEMP".
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
bool equivalent(file_status A, file_status B)
Do file_status&#39;s represent the same thing?
CD_CreateAlways - When opening a file:
Definition: FileSystem.h:689
static const char * name
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
bool home_directory(SmallVectorImpl< char > &result)
Get the user&#39;s home directory.
std::error_code access(const Twine &Path, AccessMode Mode)
Can the file be accessed?
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
CD_OpenAlways - When opening a file:
Definition: FileSystem.h:704
TimePoint getLastAccessedTime() const
bool exists(const basic_file_status &status)
Does file exist?
Definition: Path.cpp:1014
void resize(size_type N)
Definition: SmallVector.h:352