LLVM  6.0.0svn
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 #if HAVE_DIRENT_H
35 # include <dirent.h>
36 # define NAMLEN(dirent) strlen((dirent)->d_name)
37 #else
38 # define dirent direct
39 # define NAMLEN(dirent) (dirent)->d_namlen
40 # if HAVE_SYS_NDIR_H
41 # include <sys/ndir.h>
42 # endif
43 # if HAVE_SYS_DIR_H
44 # include <sys/dir.h>
45 # endif
46 # if HAVE_NDIR_H
47 # include <ndir.h>
48 # endif
49 #endif
50 
51 #include <pwd.h>
52 
53 #ifdef __APPLE__
54 #include <mach-o/dyld.h>
55 #include <sys/attr.h>
56 #endif
57 
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
60 // either.
61 #undef ferror
62 #undef feof
63 
64 // For GNU Hurd
65 #if defined(__GNU__) && !defined(PATH_MAX)
66 # define PATH_MAX 4096
67 #endif
68 
69 #include <sys/types.h>
70 #if !defined(__APPLE__) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && \
71  !defined(__linux__)
72 #include <sys/statvfs.h>
73 #define STATVFS statvfs
74 #define FSTATVFS fstatvfs
75 #define STATVFS_F_FRSIZE(vfs) vfs.f_frsize
76 #else
77 #if defined(__OpenBSD__) || defined(__FreeBSD__)
78 #include <sys/mount.h>
79 #include <sys/param.h>
80 #elif defined(__linux__)
81 #if defined(HAVE_LINUX_MAGIC_H)
82 #include <linux/magic.h>
83 #else
84 #if defined(HAVE_LINUX_NFS_FS_H)
85 #include <linux/nfs_fs.h>
86 #endif
87 #if defined(HAVE_LINUX_SMB_H)
88 #include <linux/smb.h>
89 #endif
90 #endif
91 #include <sys/vfs.h>
92 #else
93 #include <sys/mount.h>
94 #endif
95 #define STATVFS statfs
96 #define FSTATVFS fstatfs
97 #define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
98 #endif
99 
100 #if defined(__NetBSD__)
101 #define STATVFS_F_FLAG(vfs) (vfs).f_flag
102 #else
103 #define STATVFS_F_FLAG(vfs) (vfs).f_flags
104 #endif
105 
106 using namespace llvm;
107 
108 namespace llvm {
109 namespace sys {
110 namespace fs {
111 #if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
112  defined(__minix) || defined(__FreeBSD_kernel__) || defined(__linux__) || \
113  defined(__CYGWIN__) || defined(__DragonFly__) || defined(_AIX)
114 static int
115 test_dir(char ret[PATH_MAX], const char *dir, const char *bin)
116 {
117  struct stat sb;
118  char fullpath[PATH_MAX];
119 
120  snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin);
121  if (!realpath(fullpath, ret))
122  return 1;
123  if (stat(fullpath, &sb) != 0)
124  return 1;
125 
126  return 0;
127 }
128 
129 static char *
130 getprogpath(char ret[PATH_MAX], const char *bin)
131 {
132  char *pv, *s, *t;
133 
134  /* First approach: absolute path. */
135  if (bin[0] == '/') {
136  if (test_dir(ret, "/", bin) == 0)
137  return ret;
138  return nullptr;
139  }
140 
141  /* Second approach: relative path. */
142  if (strchr(bin, '/')) {
143  char cwd[PATH_MAX];
144  if (!getcwd(cwd, PATH_MAX))
145  return nullptr;
146  if (test_dir(ret, cwd, bin) == 0)
147  return ret;
148  return nullptr;
149  }
150 
151  /* Third approach: $PATH */
152  if ((pv = getenv("PATH")) == nullptr)
153  return nullptr;
154  s = pv = strdup(pv);
155  if (!pv)
156  return nullptr;
157  while ((t = strsep(&s, ":")) != nullptr) {
158  if (test_dir(ret, t, bin) == 0) {
159  free(pv);
160  return ret;
161  }
162  }
163  free(pv);
164  return nullptr;
165 }
166 #endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
167 
168 /// GetMainExecutable - Return the path to the main executable, given the
169 /// value of argv[0] from program startup.
170 std::string getMainExecutable(const char *argv0, void *MainAddr) {
171 #if defined(__APPLE__)
172  // On OS X the executable path is saved to the stack by dyld. Reading it
173  // from there is much faster than calling dladdr, especially for large
174  // binaries with symbols.
175  char exe_path[MAXPATHLEN];
176  uint32_t size = sizeof(exe_path);
177  if (_NSGetExecutablePath(exe_path, &size) == 0) {
178  char link_path[MAXPATHLEN];
179  if (realpath(exe_path, link_path))
180  return link_path;
181  }
182 #elif defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
183  defined(__minix) || defined(__DragonFly__) || \
184  defined(__FreeBSD_kernel__) || defined(_AIX)
185  char exe_path[PATH_MAX];
186 
187  if (getprogpath(exe_path, argv0) != NULL)
188  return exe_path;
189 #elif defined(__linux__) || defined(__CYGWIN__)
190  char exe_path[MAXPATHLEN];
191  StringRef aPath("/proc/self/exe");
192  if (sys::fs::exists(aPath)) {
193  // /proc is not always mounted under Linux (chroot for example).
194  ssize_t len = readlink(aPath.str().c_str(), exe_path, sizeof(exe_path));
195  if (len >= 0)
196  return std::string(exe_path, len);
197  } else {
198  // Fall back to the classical detection.
199  if (getprogpath(exe_path, argv0))
200  return exe_path;
201  }
202 #elif defined(HAVE_DLFCN_H) && defined(HAVE_DLADDR)
203  // Use dladdr to get executable path if available.
204  Dl_info DLInfo;
205  int err = dladdr(MainAddr, &DLInfo);
206  if (err == 0)
207  return "";
208 
209  // If the filename is a symlink, we need to resolve and return the location of
210  // the actual executable.
211  char link_path[MAXPATHLEN];
212  if (realpath(DLInfo.dli_fname, link_path))
213  return link_path;
214 #else
215 #error GetMainExecutable is not implemented on this host yet.
216 #endif
217  return "";
218 }
219 
220 TimePoint<> file_status::getLastAccessedTime() const {
221  return toTimePoint(fs_st_atime);
222 }
223 
224 TimePoint<> file_status::getLastModificationTime() const {
225  return toTimePoint(fs_st_mtime);
226 }
227 
228 UniqueID file_status::getUniqueID() const {
229  return UniqueID(fs_st_dev, fs_st_ino);
230 }
231 
233  return fs_st_nlinks;
234 }
235 
236 ErrorOr<space_info> disk_space(const Twine &Path) {
237  struct STATVFS Vfs;
238  if (::STATVFS(Path.str().c_str(), &Vfs))
239  return std::error_code(errno, std::generic_category());
240  auto FrSize = STATVFS_F_FRSIZE(Vfs);
241  space_info SpaceInfo;
242  SpaceInfo.capacity = static_cast<uint64_t>(Vfs.f_blocks) * FrSize;
243  SpaceInfo.free = static_cast<uint64_t>(Vfs.f_bfree) * FrSize;
244  SpaceInfo.available = static_cast<uint64_t>(Vfs.f_bavail) * FrSize;
245  return SpaceInfo;
246 }
247 
248 std::error_code current_path(SmallVectorImpl<char> &result) {
249  result.clear();
250 
251  const char *pwd = ::getenv("PWD");
252  llvm::sys::fs::file_status PWDStatus, DotStatus;
253  if (pwd && llvm::sys::path::is_absolute(pwd) &&
254  !llvm::sys::fs::status(pwd, PWDStatus) &&
255  !llvm::sys::fs::status(".", DotStatus) &&
256  PWDStatus.getUniqueID() == DotStatus.getUniqueID()) {
257  result.append(pwd, pwd + strlen(pwd));
258  return std::error_code();
259  }
260 
261 #ifdef MAXPATHLEN
262  result.reserve(MAXPATHLEN);
263 #else
264 // For GNU Hurd
265  result.reserve(1024);
266 #endif
267 
268  while (true) {
269  if (::getcwd(result.data(), result.capacity()) == nullptr) {
270  // See if there was a real error.
271  if (errno != ENOMEM)
272  return std::error_code(errno, std::generic_category());
273  // Otherwise there just wasn't enough space.
274  result.reserve(result.capacity() * 2);
275  } else
276  break;
277  }
278 
279  result.set_size(strlen(result.data()));
280  return std::error_code();
281 }
282 
283 std::error_code set_current_path(const Twine &path) {
284  SmallString<128> path_storage;
285  StringRef p = path.toNullTerminatedStringRef(path_storage);
286 
287  if (::chdir(p.begin()) == -1)
288  return std::error_code(errno, std::generic_category());
289 
290  return std::error_code();
291 }
292 
293 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
294  perms Perms) {
295  SmallString<128> path_storage;
296  StringRef p = path.toNullTerminatedStringRef(path_storage);
297 
298  if (::mkdir(p.begin(), Perms) == -1) {
299  if (errno != EEXIST || !IgnoreExisting)
300  return std::error_code(errno, std::generic_category());
301  }
302 
303  return std::error_code();
304 }
305 
306 // Note that we are using symbolic link because hard links are not supported by
307 // all filesystems (SMB doesn't).
308 std::error_code create_link(const Twine &to, const Twine &from) {
309  // Get arguments.
310  SmallString<128> from_storage;
311  SmallString<128> to_storage;
312  StringRef f = from.toNullTerminatedStringRef(from_storage);
313  StringRef t = to.toNullTerminatedStringRef(to_storage);
314 
315  if (::symlink(t.begin(), f.begin()) == -1)
316  return std::error_code(errno, std::generic_category());
317 
318  return std::error_code();
319 }
320 
321 std::error_code create_hard_link(const Twine &to, const Twine &from) {
322  // Get arguments.
323  SmallString<128> from_storage;
324  SmallString<128> to_storage;
325  StringRef f = from.toNullTerminatedStringRef(from_storage);
326  StringRef t = to.toNullTerminatedStringRef(to_storage);
327 
328  if (::link(t.begin(), f.begin()) == -1)
329  return std::error_code(errno, std::generic_category());
330 
331  return std::error_code();
332 }
333 
334 std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
335  SmallString<128> path_storage;
336  StringRef p = path.toNullTerminatedStringRef(path_storage);
337 
338  struct stat buf;
339  if (lstat(p.begin(), &buf) != 0) {
340  if (errno != ENOENT || !IgnoreNonExisting)
341  return std::error_code(errno, std::generic_category());
342  return std::error_code();
343  }
344 
345  // Note: this check catches strange situations. In all cases, LLVM should
346  // only be involved in the creation and deletion of regular files. This
347  // check ensures that what we're trying to erase is a regular file. It
348  // effectively prevents LLVM from erasing things like /dev/null, any block
349  // special file, or other things that aren't "regular" files.
350  if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode))
352 
353  if (::remove(p.begin()) == -1) {
354  if (errno != ENOENT || !IgnoreNonExisting)
355  return std::error_code(errno, std::generic_category());
356  }
357 
358  return std::error_code();
359 }
360 
361 static bool is_local_impl(struct STATVFS &Vfs) {
362 #if defined(__linux__)
363 #ifndef NFS_SUPER_MAGIC
364 #define NFS_SUPER_MAGIC 0x6969
365 #endif
366 #ifndef SMB_SUPER_MAGIC
367 #define SMB_SUPER_MAGIC 0x517B
368 #endif
369 #ifndef CIFS_MAGIC_NUMBER
370 #define CIFS_MAGIC_NUMBER 0xFF534D42
371 #endif
372  switch ((uint32_t)Vfs.f_type) {
373  case NFS_SUPER_MAGIC:
374  case SMB_SUPER_MAGIC:
375  case CIFS_MAGIC_NUMBER:
376  return false;
377  default:
378  return true;
379  }
380 #elif defined(__CYGWIN__)
381  // Cygwin doesn't expose this information; would need to use Win32 API.
382  return false;
383 #elif defined(__sun)
384  // statvfs::f_basetype contains a null-terminated FSType name of the mounted target
385  StringRef fstype(Vfs.f_basetype);
386  // NFS is the only non-local fstype??
387  return !fstype.equals("nfs");
388 #else
389  return !!(STATVFS_F_FLAG(Vfs) & MNT_LOCAL);
390 #endif
391 }
392 
393 std::error_code is_local(const Twine &Path, bool &Result) {
394  struct STATVFS Vfs;
395  if (::STATVFS(Path.str().c_str(), &Vfs))
396  return std::error_code(errno, std::generic_category());
397 
398  Result = is_local_impl(Vfs);
399  return std::error_code();
400 }
401 
402 std::error_code is_local(int FD, bool &Result) {
403  struct STATVFS Vfs;
404  if (::FSTATVFS(FD, &Vfs))
405  return std::error_code(errno, std::generic_category());
406 
407  Result = is_local_impl(Vfs);
408  return std::error_code();
409 }
410 
411 std::error_code rename(const Twine &from, const Twine &to) {
412  // Get arguments.
413  SmallString<128> from_storage;
414  SmallString<128> to_storage;
415  StringRef f = from.toNullTerminatedStringRef(from_storage);
416  StringRef t = to.toNullTerminatedStringRef(to_storage);
417 
418  if (::rename(f.begin(), t.begin()) == -1)
419  return std::error_code(errno, std::generic_category());
420 
421  return std::error_code();
422 }
423 
424 std::error_code resize_file(int FD, uint64_t Size) {
425 #if defined(HAVE_POSIX_FALLOCATE)
426  // If we have posix_fallocate use it. Unlike ftruncate it always allocates
427  // space, so we get an error if the disk is full.
428  if (int Err = ::posix_fallocate(FD, 0, Size)) {
429  if (Err != EOPNOTSUPP)
430  return std::error_code(Err, std::generic_category());
431  }
432 #endif
433  // Use ftruncate as a fallback. It may or may not allocate space. At least on
434  // OS X with HFS+ it does.
435  if (::ftruncate(FD, Size) == -1)
436  return std::error_code(errno, std::generic_category());
437 
438  return std::error_code();
439 }
440 
441 static int convertAccessMode(AccessMode Mode) {
442  switch (Mode) {
443  case AccessMode::Exist:
444  return F_OK;
445  case AccessMode::Write:
446  return W_OK;
447  case AccessMode::Execute:
448  return R_OK | X_OK; // scripts also need R_OK.
449  }
450  llvm_unreachable("invalid enum");
451 }
452 
453 std::error_code access(const Twine &Path, AccessMode Mode) {
454  SmallString<128> PathStorage;
455  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
456 
457  if (::access(P.begin(), convertAccessMode(Mode)) == -1)
458  return std::error_code(errno, std::generic_category());
459 
460  if (Mode == AccessMode::Execute) {
461  // Don't say that directories are executable.
462  struct stat buf;
463  if (0 != stat(P.begin(), &buf))
465  if (!S_ISREG(buf.st_mode))
467  }
468 
469  return std::error_code();
470 }
471 
472 bool can_execute(const Twine &Path) {
473  return !access(Path, AccessMode::Execute);
474 }
475 
476 bool equivalent(file_status A, file_status B) {
477  assert(status_known(A) && status_known(B));
478  return A.fs_st_dev == B.fs_st_dev &&
479  A.fs_st_ino == B.fs_st_ino;
480 }
481 
482 std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
483  file_status fsA, fsB;
484  if (std::error_code ec = status(A, fsA))
485  return ec;
486  if (std::error_code ec = status(B, fsB))
487  return ec;
488  result = equivalent(fsA, fsB);
489  return std::error_code();
490 }
491 
492 static void expandTildeExpr(SmallVectorImpl<char> &Path) {
493  StringRef PathStr(Path.begin(), Path.size());
494  if (PathStr.empty() || !PathStr.startswith("~"))
495  return;
496 
497  PathStr = PathStr.drop_front();
498  StringRef Expr =
499  PathStr.take_until([](char c) { return path::is_separator(c); });
500  StringRef Remainder = PathStr.substr(Expr.size() + 1);
501  SmallString<128> Storage;
502  if (Expr.empty()) {
503  // This is just ~/..., resolve it to the current user's home dir.
504  if (!path::home_directory(Storage)) {
505  // For some reason we couldn't get the home directory. Just exit.
506  return;
507  }
508 
509  // Overwrite the first character and insert the rest.
510  Path[0] = Storage[0];
511  Path.insert(Path.begin() + 1, Storage.begin() + 1, Storage.end());
512  return;
513  }
514 
515  // This is a string of the form ~username/, look up this user's entry in the
516  // password database.
517  struct passwd *Entry = nullptr;
518  std::string User = Expr.str();
519  Entry = ::getpwnam(User.c_str());
520 
521  if (!Entry) {
522  // Unable to look up the entry, just return back the original path.
523  return;
524  }
525 
526  Storage = Remainder;
527  Path.clear();
528  Path.append(Entry->pw_dir, Entry->pw_dir + strlen(Entry->pw_dir));
529  llvm::sys::path::append(Path, Storage);
530 }
531 
532 static std::error_code fillStatus(int StatRet, const struct stat &Status,
533  file_status &Result) {
534  if (StatRet != 0) {
535  std::error_code ec(errno, std::generic_category());
537  Result = file_status(file_type::file_not_found);
538  else
539  Result = file_status(file_type::status_error);
540  return ec;
541  }
542 
544 
545  if (S_ISDIR(Status.st_mode))
547  else if (S_ISREG(Status.st_mode))
549  else if (S_ISBLK(Status.st_mode))
550  Type = file_type::block_file;
551  else if (S_ISCHR(Status.st_mode))
553  else if (S_ISFIFO(Status.st_mode))
554  Type = file_type::fifo_file;
555  else if (S_ISSOCK(Status.st_mode))
556  Type = file_type::socket_file;
557  else if (S_ISLNK(Status.st_mode))
559 
560  perms Perms = static_cast<perms>(Status.st_mode) & all_perms;
561  Result = file_status(Type, Perms, Status.st_dev, Status.st_nlink,
562  Status.st_ino, Status.st_atime, Status.st_mtime,
563  Status.st_uid, Status.st_gid, Status.st_size);
564 
565  return std::error_code();
566 }
567 
568 std::error_code status(const Twine &Path, file_status &Result, bool Follow) {
569  SmallString<128> PathStorage;
570  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
571 
572  struct stat Status;
573  int StatRet = (Follow ? ::stat : ::lstat)(P.begin(), &Status);
574  return fillStatus(StatRet, Status, Result);
575 }
576 
577 std::error_code status(int FD, file_status &Result) {
578  struct stat Status;
579  int StatRet = ::fstat(FD, &Status);
580  return fillStatus(StatRet, Status, Result);
581 }
582 
583 std::error_code setPermissions(const Twine &Path, perms Permissions) {
584  SmallString<128> PathStorage;
585  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
586 
587  if (::chmod(P.begin(), Permissions))
588  return std::error_code(errno, std::generic_category());
589  return std::error_code();
590 }
591 
592 std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) {
593 #if defined(HAVE_FUTIMENS)
594  timespec Times[2];
595  Times[0] = Times[1] = sys::toTimeSpec(Time);
596  if (::futimens(FD, Times))
597  return std::error_code(errno, std::generic_category());
598  return std::error_code();
599 #elif defined(HAVE_FUTIMES)
600  timeval Times[2];
601  Times[0] = Times[1] = sys::toTimeVal(
602  std::chrono::time_point_cast<std::chrono::microseconds>(Time));
603  if (::futimes(FD, Times))
604  return std::error_code(errno, std::generic_category());
605  return std::error_code();
606 #else
607 #warning Missing futimes() and futimens()
609 #endif
610 }
611 
612 std::error_code mapped_file_region::init(int FD, uint64_t Offset,
613  mapmode Mode) {
614  assert(Size != 0);
615 
616  int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
617  int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
618 #if defined(__APPLE__)
619  //----------------------------------------------------------------------
620  // Newer versions of MacOSX have a flag that will allow us to read from
621  // binaries whose code signature is invalid without crashing by using
622  // the MAP_RESILIENT_CODESIGN flag. Also if a file from removable media
623  // is mapped we can avoid crashing and return zeroes to any pages we try
624  // to read if the media becomes unavailable by using the
625  // MAP_RESILIENT_MEDIA flag. These flags are only usable when mapping
626  // with PROT_READ, so take care not to specify them otherwise.
627  //----------------------------------------------------------------------
628  if (Mode == readonly) {
629 #if defined(MAP_RESILIENT_CODESIGN)
630  flags |= MAP_RESILIENT_CODESIGN;
631 #endif
632 #if defined(MAP_RESILIENT_MEDIA)
633  flags |= MAP_RESILIENT_MEDIA;
634 #endif
635  }
636 #endif // #if defined (__APPLE__)
637 
638  Mapping = ::mmap(nullptr, Size, prot, flags, FD, Offset);
639  if (Mapping == MAP_FAILED)
640  return std::error_code(errno, std::generic_category());
641  return std::error_code();
642 }
643 
644 mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length,
645  uint64_t offset, std::error_code &ec)
646  : Size(length), Mapping() {
647  // Make sure that the requested size fits within SIZE_T.
648  if (length > std::numeric_limits<size_t>::max()) {
650  return;
651  }
652 
653  ec = init(fd, offset, mode);
654  if (ec)
655  Mapping = nullptr;
656 }
657 
658 mapped_file_region::~mapped_file_region() {
659  if (Mapping)
660  ::munmap(Mapping, Size);
661 }
662 
663 uint64_t mapped_file_region::size() const {
664  assert(Mapping && "Mapping failed but used anyway!");
665  return Size;
666 }
667 
668 char *mapped_file_region::data() const {
669  assert(Mapping && "Mapping failed but used anyway!");
670  return reinterpret_cast<char*>(Mapping);
671 }
672 
673 const char *mapped_file_region::const_data() const {
674  assert(Mapping && "Mapping failed but used anyway!");
675  return reinterpret_cast<const char*>(Mapping);
676 }
677 
678 int mapped_file_region::alignment() {
679  return Process::getPageSize();
680 }
681 
682 std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
683  StringRef path,
684  bool follow_symlinks) {
685  SmallString<128> path_null(path);
686  DIR *directory = ::opendir(path_null.c_str());
687  if (!directory)
688  return std::error_code(errno, std::generic_category());
689 
690  it.IterationHandle = reinterpret_cast<intptr_t>(directory);
691  // Add something for replace_filename to replace.
692  path::append(path_null, ".");
693  it.CurrentEntry = directory_entry(path_null.str(), follow_symlinks);
694  return directory_iterator_increment(it);
695 }
696 
697 std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
698  if (it.IterationHandle)
699  ::closedir(reinterpret_cast<DIR *>(it.IterationHandle));
700  it.IterationHandle = 0;
701  it.CurrentEntry = directory_entry();
702  return std::error_code();
703 }
704 
705 std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
706  errno = 0;
707  dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle));
708  if (cur_dir == nullptr && errno != 0) {
709  return std::error_code(errno, std::generic_category());
710  } else if (cur_dir != nullptr) {
711  StringRef name(cur_dir->d_name, NAMLEN(cur_dir));
712  if ((name.size() == 1 && name[0] == '.') ||
713  (name.size() == 2 && name[0] == '.' && name[1] == '.'))
714  return directory_iterator_increment(it);
715  it.CurrentEntry.replace_filename(name);
716  } else
717  return directory_iterator_destruct(it);
718 
719  return std::error_code();
720 }
721 
722 #if !defined(F_GETPATH)
723 static bool hasProcSelfFD() {
724  // If we have a /proc filesystem mounted, we can quickly establish the
725  // real name of the file with readlink
726  static const bool Result = (::access("/proc/self/fd", R_OK) == 0);
727  return Result;
728 }
729 #endif
730 
731 std::error_code openFileForRead(const Twine &Name, int &ResultFD,
732  SmallVectorImpl<char> *RealPath) {
733  SmallString<128> Storage;
734  StringRef P = Name.toNullTerminatedStringRef(Storage);
735  int OpenFlags = O_RDONLY;
736 #ifdef O_CLOEXEC
737  OpenFlags |= O_CLOEXEC;
738 #endif
739  if ((ResultFD = sys::RetryAfterSignal(-1, open, P.begin(), OpenFlags)) < 0)
740  return std::error_code(errno, std::generic_category());
741 #ifndef O_CLOEXEC
742  int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC);
743  (void)r;
744  assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed");
745 #endif
746  // Attempt to get the real name of the file, if the user asked
747  if(!RealPath)
748  return std::error_code();
749  RealPath->clear();
750 #if defined(F_GETPATH)
751  // When F_GETPATH is availble, it is the quickest way to get
752  // the real path name.
753  char Buffer[MAXPATHLEN];
754  if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1)
755  RealPath->append(Buffer, Buffer + strlen(Buffer));
756 #else
757  char Buffer[PATH_MAX];
758  if (hasProcSelfFD()) {
759  char ProcPath[64];
760  snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
761  ssize_t CharCount = ::readlink(ProcPath, Buffer, sizeof(Buffer));
762  if (CharCount > 0)
763  RealPath->append(Buffer, Buffer + CharCount);
764  } else {
765  // Use ::realpath to get the real path name
766  if (::realpath(P.begin(), Buffer) != nullptr)
767  RealPath->append(Buffer, Buffer + strlen(Buffer));
768  }
769 #endif
770  return std::error_code();
771 }
772 
773 std::error_code openFileForWrite(const Twine &Name, int &ResultFD,
774  sys::fs::OpenFlags Flags, unsigned Mode) {
775  // Verify that we don't have both "append" and "excl".
776  assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
777  "Cannot specify both 'excl' and 'append' file creation flags!");
778 
779  int OpenFlags = O_CREAT;
780 
781 #ifdef O_CLOEXEC
782  OpenFlags |= O_CLOEXEC;
783 #endif
784 
785  if (Flags & F_RW)
786  OpenFlags |= O_RDWR;
787  else
788  OpenFlags |= O_WRONLY;
789 
790  if (Flags & F_Append)
791  OpenFlags |= O_APPEND;
792  else
793  OpenFlags |= O_TRUNC;
794 
795  if (Flags & F_Excl)
796  OpenFlags |= O_EXCL;
797 
798  SmallString<128> Storage;
799  StringRef P = Name.toNullTerminatedStringRef(Storage);
800  if ((ResultFD = sys::RetryAfterSignal(-1, open, P.begin(), OpenFlags, Mode)) < 0)
801  return std::error_code(errno, std::generic_category());
802 #ifndef O_CLOEXEC
803  int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC);
804  (void)r;
805  assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed");
806 #endif
807  return std::error_code();
808 }
809 
810 std::error_code getPathFromOpenFD(int FD, SmallVectorImpl<char> &ResultPath) {
811  if (FD < 0)
813 
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());
820 
821  ResultPath.set_size(strlen(ResultPath.begin()));
822 #else
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())
828 
829  ResultPath.reserve(PATH_MAX);
830  char ProcPath[64];
831  snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", FD);
832  ssize_t CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
833  if (CharCount < 0)
834  return std::error_code(errno, std::generic_category());
835 
836  // Was the filename truncated?
837  if (static_cast<size_t>(CharCount) == ResultPath.capacity()) {
838  // Use lstat to get the size of the filename
839  struct stat sb;
840  if (::lstat(ProcPath, &sb) < 0)
841  return std::error_code(errno, std::generic_category());
842 
843  ResultPath.reserve(sb.st_size + 1);
844  CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
845  if (CharCount < 0)
846  return std::error_code(errno, std::generic_category());
847 
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());
851  }
852  ResultPath.set_size(static_cast<size_t>(CharCount));
853 #endif
854  return std::error_code();
855 }
856 
857 template <typename T>
858 static std::error_code remove_directories_impl(const T &Entry,
859  bool IgnoreErrors) {
860  std::error_code EC;
861  directory_iterator Begin(Entry, EC, false);
862  directory_iterator End;
863  while (Begin != End) {
864  auto &Item = *Begin;
865  file_status st;
866  EC = Item.status(st);
867  if (EC && !IgnoreErrors)
868  return EC;
869 
870  if (is_directory(st)) {
871  EC = remove_directories_impl(Item, IgnoreErrors);
872  if (EC && !IgnoreErrors)
873  return EC;
874  }
875 
876  EC = fs::remove(Item.path(), true);
877  if (EC && !IgnoreErrors)
878  return EC;
879 
880  Begin.increment(EC);
881  if (EC && !IgnoreErrors)
882  return EC;
883  }
884  return std::error_code();
885 }
886 
887 std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
888  auto EC = remove_directories_impl(path, IgnoreErrors);
889  if (EC && !IgnoreErrors)
890  return EC;
891  EC = fs::remove(path, true);
892  if (EC && !IgnoreErrors)
893  return EC;
894  return std::error_code();
895 }
896 
897 std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,
898  bool expand_tilde) {
899  dest.clear();
900  if (path.isTriviallyEmpty())
901  return std::error_code();
902 
903  if (expand_tilde) {
904  SmallString<128> Storage;
905  path.toVector(Storage);
906  expandTildeExpr(Storage);
907  return real_path(Storage, dest, false);
908  }
909 
910  int fd;
911  std::error_code EC = openFileForRead(path, fd, &dest);
912 
913  if (EC)
914  return EC;
915  ::close(fd);
916  return std::error_code();
917 }
918 
919 } // end namespace fs
920 
921 namespace path {
922 
924  char *RequestedDir = getenv("HOME");
925  if (!RequestedDir) {
926  struct passwd *pw = getpwuid(getuid());
927  if (pw && pw->pw_dir)
928  RequestedDir = pw->pw_dir;
929  }
930  if (!RequestedDir)
931  return false;
932 
933  result.clear();
934  result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
935  return true;
936 }
937 
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);
945  if (ConfLen > 0) {
946  do {
947  Result.resize(ConfLen);
948  ConfLen = confstr(ConfName, Result.data(), Result.size());
949  } while (ConfLen > 0 && ConfLen != Result.size());
950 
951  if (ConfLen > 0) {
952  assert(Result.back() == 0);
953  Result.pop_back();
954  return true;
955  }
956 
957  Result.clear();
958  }
959  #endif
960  return false;
961 }
962 
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")) {
968  Result.clear();
969  Result.append(XdgCacheDir, XdgCacheDir + strlen(XdgCacheDir));
970  return true;
971  }
972 
973  // Try Darwin configuration query
974  if (getDarwinConfDir(false, Result))
975  return true;
976 
977  // Use "$HOME/.cache" if $HOME is available
978  if (home_directory(Result)) {
979  append(Result, ".cache");
980  return true;
981  }
982 
983  return false;
984 }
985 
986 static const char *getEnvTempDir() {
987  // Check whether the temporary directory is specified by an environment
988  // variable.
989  const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
990  for (const char *Env : EnvironmentVariables) {
991  if (const char *Dir = std::getenv(Env))
992  return Dir;
993  }
994 
995  return nullptr;
996 }
997 
998 static const char *getDefaultTempDir(bool ErasedOnReboot) {
999 #ifdef P_tmpdir
1000  if ((bool)P_tmpdir)
1001  return P_tmpdir;
1002 #endif
1003 
1004  if (ErasedOnReboot)
1005  return "/tmp";
1006  return "/var/tmp";
1007 }
1008 
1009 void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
1010  Result.clear();
1011 
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));
1016  return;
1017  }
1018  }
1019 
1020  if (getDarwinConfDir(ErasedOnReboot, Result))
1021  return;
1022 
1023  const char *RequestedDir = getDefaultTempDir(ErasedOnReboot);
1024  Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
1025 }
1026 
1027 } // end namespace path
1028 
1029 } // end namespace sys
1030 } // end namespace llvm
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:603
F_Append - When opening a file, if it already exists append to the existing file instead of returning...
Definition: FileSystem.h:704
bool can_execute(const Twine &Path)
Can we execute this file?
Represents either an error or a value T.
Definition: ErrorOr.h:69
GCNRegPressure max(const GCNRegPressure &P1, const GCNRegPressure &P2)
LLVM_NODISCARD std::string str() const
str - Get the contents as an std::string.
Definition: StringRef.h:228
SI Whole Quad Mode
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:136
std::error_code openFileForRead(const Twine &Name, int &ResultFD, SmallVectorImpl< char > *RealPath=nullptr)
std::error_code remove(const Twine &path, bool IgnoreNonExisting=true)
Remove path.
F_Excl - When opening a file, this flag makes raw_fd_ostream report an error if the file already exis...
Definition: FileSystem.h:699
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:408
TimePoint getLastAccessedTime() const
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.
void reserve(size_type N)
Definition: SmallVector.h:380
std::error_code remove_directories(const Twine &path, bool IgnoreErrors=true)
Recursively delete a directory.
file_status - Represents the result of a call to stat and friends.
Definition: FileSystem.h:146
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
bool status_known(file_status s)
Is status available?
Definition: Path.cpp:960
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:465
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
static F t[256]
std::error_code make_error_code(BitcodeError E)
bool is_absolute(const Twine &path, Style style=Style::native)
Is path absolute?
Definition: Path.cpp:673
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
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.
Open the file for read and write.
Definition: FileSystem.h:711
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
const char * Name
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:404
TimePoint getLastModificationTime() const
size_t capacity() const
Return the total number of elements in the currently allocated buffer.
Definition: SmallVector.h:140
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
static char * argv0
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:116
uint32_t getLinkCount() const
#define A
Definition: LargeTest.cpp:12
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:37
static const unsigned End
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
friend bool equivalent(file_status A, file_status B)
Do file_status&#39;s represent the same thing?
std::error_code getPathFromOpenFD(int FD, SmallVectorImpl< char > &ResultPath)
Fetch a path to an open file, as specified by a file descriptor.
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:32
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
bool is_directory(file_status status)
Does status represent a directory?
Definition: Path.cpp:971
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
std::error_code directory_iterator_construct(DirIterState &, StringRef, bool)
#define B
Definition: LargeTest.cpp:24
std::error_code setPermissions(const Twine &Path, perms Permissions)
Set file permissions.
iterator insert(iterator I, T &&Elt)
Definition: SmallVector.h:482
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:398
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
static std::vector< std::string > Flags
Definition: FlagsTest.cpp:8
ErrorOr< space_info > disk_space(const Twine &Path)
Get disk space usage information.
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator end()
Definition: SmallVector.h:120
void set_size(size_type N)
Set the array size to N, which the current array must have enough capacity for.
Definition: SmallVector.h:689
std::error_code directory_iterator_destruct(DirIterState &)
pointer data()
Return a pointer to the vector&#39;s buffer, even if empty().
Definition: SmallVector.h:143
file_type
An enumeration for the file system&#39;s view of the type.
Definition: FileSystem.h:56
std::error_code create_directory(const Twine &path, bool IgnoreExisting=true, perms Perms=owner_all|group_all)
Create the directory in path.
std::string str() const
Return the twine contents as a std::string.
Definition: Twine.cpp:17
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())
static const char * name
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
bool exists(file_status status)
Does file exist?
Definition: Path.cpp:956
void resize(size_type N)
Definition: SmallVector.h:355
std::error_code openFileForWrite(const Twine &Name, int &ResultFD, OpenFlags Flags, unsigned Mode=0666)