LLVM  4.0.0
Unix/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 #ifdef __APPLE__
52 #include <mach-o/dyld.h>
53 #include <sys/attr.h>
54 #endif
55 
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
58 // either.
59 #undef ferror
60 #undef feof
61 
62 // For GNU Hurd
63 #if defined(__GNU__) && !defined(PATH_MAX)
64 # define PATH_MAX 4096
65 #endif
66 
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
72 #else
73 #ifdef __OpenBSD__
74 #include <sys/param.h>
75 #include <sys/mount.h>
76 #elif defined(__ANDROID__)
77 #include <sys/vfs.h>
78 #else
79 #include <sys/mount.h>
80 #endif
81 #define STATVFS statfs
82 #define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
83 #endif
84 
85 
86 using namespace llvm;
87 
88 namespace llvm {
89 namespace sys {
90 namespace fs {
91 #if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
92  defined(__OpenBSD__) || defined(__minix) || defined(__FreeBSD_kernel__) || \
93  defined(__linux__) || defined(__CYGWIN__) || defined(__DragonFly__) || \
94  defined(_AIX)
95 static int
96 test_dir(char ret[PATH_MAX], const char *dir, const char *bin)
97 {
98  struct stat sb;
99  char fullpath[PATH_MAX];
100 
101  snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin);
102  if (!realpath(fullpath, ret))
103  return 1;
104  if (stat(fullpath, &sb) != 0)
105  return 1;
106 
107  return 0;
108 }
109 
110 static char *
111 getprogpath(char ret[PATH_MAX], const char *bin)
112 {
113  char *pv, *s, *t;
114 
115  /* First approach: absolute path. */
116  if (bin[0] == '/') {
117  if (test_dir(ret, "/", bin) == 0)
118  return ret;
119  return nullptr;
120  }
121 
122  /* Second approach: relative path. */
123  if (strchr(bin, '/')) {
124  char cwd[PATH_MAX];
125  if (!getcwd(cwd, PATH_MAX))
126  return nullptr;
127  if (test_dir(ret, cwd, bin) == 0)
128  return ret;
129  return nullptr;
130  }
131 
132  /* Third approach: $PATH */
133  if ((pv = getenv("PATH")) == nullptr)
134  return nullptr;
135  s = pv = strdup(pv);
136  if (!pv)
137  return nullptr;
138  while ((t = strsep(&s, ":")) != nullptr) {
139  if (test_dir(ret, t, bin) == 0) {
140  free(pv);
141  return ret;
142  }
143  }
144  free(pv);
145  return nullptr;
146 }
147 #endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
148 
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))
161  return link_path;
162  }
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];
167 
168  if (getprogpath(exe_path, argv0) != NULL)
169  return exe_path;
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));
176  if (len >= 0)
177  return std::string(exe_path, len);
178  } else {
179  // Fall back to the classical detection.
180  if (getprogpath(exe_path, argv0))
181  return exe_path;
182  }
183 #elif defined(HAVE_DLFCN_H)
184  // Use dladdr to get executable path if available.
185  Dl_info DLInfo;
186  int err = dladdr(MainAddr, &DLInfo);
187  if (err == 0)
188  return "";
189 
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))
194  return link_path;
195 #else
196 #error GetMainExecutable is not implemented on this host yet.
197 #endif
198  return "";
199 }
200 
201 TimePoint<> file_status::getLastAccessedTime() const {
202  return toTimePoint(fs_st_atime);
203 }
204 
205 TimePoint<> file_status::getLastModificationTime() const {
206  return toTimePoint(fs_st_mtime);
207 }
208 
209 UniqueID file_status::getUniqueID() const {
210  return UniqueID(fs_st_dev, fs_st_ino);
211 }
212 
213 ErrorOr<space_info> disk_space(const Twine &Path) {
214  struct STATVFS Vfs;
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;
222  return SpaceInfo;
223 }
224 
225 std::error_code current_path(SmallVectorImpl<char> &result) {
226  result.clear();
227 
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();
236  }
237 
238 #ifdef MAXPATHLEN
239  result.reserve(MAXPATHLEN);
240 #else
241 // For GNU Hurd
242  result.reserve(1024);
243 #endif
244 
245  while (true) {
246  if (::getcwd(result.data(), result.capacity()) == nullptr) {
247  // See if there was a real error.
248  if (errno != ENOMEM)
249  return std::error_code(errno, std::generic_category());
250  // Otherwise there just wasn't enough space.
251  result.reserve(result.capacity() * 2);
252  } else
253  break;
254  }
255 
256  result.set_size(strlen(result.data()));
257  return std::error_code();
258 }
259 
260 std::error_code create_directory(const Twine &path, bool IgnoreExisting,
261  perms Perms) {
262  SmallString<128> path_storage;
263  StringRef p = path.toNullTerminatedStringRef(path_storage);
264 
265  if (::mkdir(p.begin(), Perms) == -1) {
266  if (errno != EEXIST || !IgnoreExisting)
267  return std::error_code(errno, std::generic_category());
268  }
269 
270  return std::error_code();
271 }
272 
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) {
276  // Get arguments.
277  SmallString<128> from_storage;
278  SmallString<128> to_storage;
279  StringRef f = from.toNullTerminatedStringRef(from_storage);
280  StringRef t = to.toNullTerminatedStringRef(to_storage);
281 
282  if (::symlink(t.begin(), f.begin()) == -1)
283  return std::error_code(errno, std::generic_category());
284 
285  return std::error_code();
286 }
287 
288 std::error_code create_hard_link(const Twine &to, const Twine &from) {
289  // Get arguments.
290  SmallString<128> from_storage;
291  SmallString<128> to_storage;
292  StringRef f = from.toNullTerminatedStringRef(from_storage);
293  StringRef t = to.toNullTerminatedStringRef(to_storage);
294 
295  if (::link(t.begin(), f.begin()) == -1)
296  return std::error_code(errno, std::generic_category());
297 
298  return std::error_code();
299 }
300 
301 std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
302  SmallString<128> path_storage;
303  StringRef p = path.toNullTerminatedStringRef(path_storage);
304 
305  struct stat buf;
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();
310  }
311 
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))
319 
320  if (::remove(p.begin()) == -1) {
321  if (errno != ENOENT || !IgnoreNonExisting)
322  return std::error_code(errno, std::generic_category());
323  }
324 
325  return std::error_code();
326 }
327 
328 std::error_code rename(const Twine &from, const Twine &to) {
329  // Get arguments.
330  SmallString<128> from_storage;
331  SmallString<128> to_storage;
332  StringRef f = from.toNullTerminatedStringRef(from_storage);
333  StringRef t = to.toNullTerminatedStringRef(to_storage);
334 
335  if (::rename(f.begin(), t.begin()) == -1)
336  return std::error_code(errno, std::generic_category());
337 
338  return std::error_code();
339 }
340 
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());
347 #else
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());
352 #endif
353 
354  return std::error_code();
355 }
356 
357 static int convertAccessMode(AccessMode Mode) {
358  switch (Mode) {
359  case AccessMode::Exist:
360  return F_OK;
361  case AccessMode::Write:
362  return W_OK;
363  case AccessMode::Execute:
364  return R_OK | X_OK; // scripts also need R_OK.
365  }
366  llvm_unreachable("invalid enum");
367 }
368 
369 std::error_code access(const Twine &Path, AccessMode Mode) {
370  SmallString<128> PathStorage;
371  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
372 
373  if (::access(P.begin(), convertAccessMode(Mode)) == -1)
374  return std::error_code(errno, std::generic_category());
375 
376  if (Mode == AccessMode::Execute) {
377  // Don't say that directories are executable.
378  struct stat buf;
379  if (0 != stat(P.begin(), &buf))
381  if (!S_ISREG(buf.st_mode))
383  }
384 
385  return std::error_code();
386 }
387 
388 bool can_execute(const Twine &Path) {
389  return !access(Path, AccessMode::Execute);
390 }
391 
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;
396 }
397 
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))
401  return ec;
402  if (std::error_code ec = status(B, fsB))
403  return ec;
404  result = equivalent(fsA, fsB);
405  return std::error_code();
406 }
407 
408 static std::error_code fillStatus(int StatRet, const struct stat &Status,
409  file_status &Result) {
410  if (StatRet != 0) {
411  std::error_code ec(errno, std::generic_category());
413  Result = file_status(file_type::file_not_found);
414  else
415  Result = file_status(file_type::status_error);
416  return ec;
417  }
418 
420 
421  if (S_ISDIR(Status.st_mode))
423  else if (S_ISREG(Status.st_mode))
425  else if (S_ISBLK(Status.st_mode))
426  Type = file_type::block_file;
427  else if (S_ISCHR(Status.st_mode))
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;
433 
434  perms Perms = static_cast<perms>(Status.st_mode);
435  Result =
436  file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_atime,
437  Status.st_mtime, Status.st_uid, Status.st_gid,
438  Status.st_size);
439 
440  return std::error_code();
441 }
442 
443 std::error_code status(const Twine &Path, file_status &Result) {
444  SmallString<128> PathStorage;
445  StringRef P = Path.toNullTerminatedStringRef(PathStorage);
446 
447  struct stat Status;
448  int StatRet = ::stat(P.begin(), &Status);
449  return fillStatus(StatRet, Status, Result);
450 }
451 
452 std::error_code status(int FD, file_status &Result) {
453  struct stat Status;
454  int StatRet = ::fstat(FD, &Status);
455  return fillStatus(StatRet, Status, Result);
456 }
457 
458 std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) {
459 #if defined(HAVE_FUTIMENS)
460  timespec Times[2];
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)
466  timeval Times[2];
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();
472 #else
473 #warning Missing futimes() and futimens()
475 #endif
476 }
477 
478 std::error_code mapped_file_region::init(int FD, uint64_t Offset,
479  mapmode Mode) {
480  assert(Size != 0);
481 
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();
488 }
489 
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()) {
496  return;
497  }
498 
499  ec = init(fd, offset, mode);
500  if (ec)
501  Mapping = nullptr;
502 }
503 
504 mapped_file_region::~mapped_file_region() {
505  if (Mapping)
506  ::munmap(Mapping, Size);
507 }
508 
509 uint64_t mapped_file_region::size() const {
510  assert(Mapping && "Mapping failed but used anyway!");
511  return Size;
512 }
513 
514 char *mapped_file_region::data() const {
515  assert(Mapping && "Mapping failed but used anyway!");
516  return reinterpret_cast<char*>(Mapping);
517 }
518 
519 const char *mapped_file_region::const_data() const {
520  assert(Mapping && "Mapping failed but used anyway!");
521  return reinterpret_cast<const char*>(Mapping);
522 }
523 
524 int mapped_file_region::alignment() {
525  return Process::getPageSize();
526 }
527 
528 std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
529  StringRef path){
530  SmallString<128> path_null(path);
531  DIR *directory = ::opendir(path_null.c_str());
532  if (!directory)
533  return std::error_code(errno, std::generic_category());
534 
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);
540 }
541 
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();
548 }
549 
550 std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
551  errno = 0;
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);
561  } else
562  return directory_iterator_destruct(it);
563 
564  return std::error_code();
565 }
566 
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);
572  return Result;
573 }
574 #endif
575 
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) {
581  if (errno != EINTR)
582  return std::error_code(errno, std::generic_category());
583  }
584  // Attempt to get the real name of the file, if the user asked
585  if(!RealPath)
586  return std::error_code();
587  RealPath->clear();
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));
594 #else
595  char Buffer[PATH_MAX];
596  if (hasProcSelfFD()) {
597  char ProcPath[64];
598  snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
599  ssize_t CharCount = ::readlink(ProcPath, Buffer, sizeof(Buffer));
600  if (CharCount > 0)
601  RealPath->append(Buffer, Buffer + CharCount);
602  } else {
603  // Use ::realpath to get the real path name
604  if (::realpath(P.begin(), Buffer) != nullptr)
605  RealPath->append(Buffer, Buffer + strlen(Buffer));
606  }
607 #endif
608  return std::error_code();
609 }
610 
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!");
616 
617  int OpenFlags = O_CREAT;
618 
619  if (Flags & F_RW)
620  OpenFlags |= O_RDWR;
621  else
622  OpenFlags |= O_WRONLY;
623 
624  if (Flags & F_Append)
625  OpenFlags |= O_APPEND;
626  else
627  OpenFlags |= O_TRUNC;
628 
629  if (Flags & F_Excl)
630  OpenFlags |= O_EXCL;
631 
632  SmallString<128> Storage;
633  StringRef P = Name.toNullTerminatedStringRef(Storage);
634  while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) {
635  if (errno != EINTR)
636  return std::error_code(errno, std::generic_category());
637  }
638  return std::error_code();
639 }
640 
641 std::error_code getPathFromOpenFD(int FD, SmallVectorImpl<char> &ResultPath) {
642  if (FD < 0)
644 
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());
651 
652  ResultPath.set_size(strlen(ResultPath.begin()));
653 #else
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())
659 
660  ResultPath.reserve(PATH_MAX);
661  char ProcPath[64];
662  snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", FD);
663  ssize_t CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
664  if (CharCount < 0)
665  return std::error_code(errno, std::generic_category());
666 
667  // Was the filename truncated?
668  if (static_cast<size_t>(CharCount) == ResultPath.capacity()) {
669  // Use lstat to get the size of the filename
670  struct stat sb;
671  if (::lstat(ProcPath, &sb) < 0)
672  return std::error_code(errno, std::generic_category());
673 
674  ResultPath.reserve(sb.st_size + 1);
675  CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity());
676  if (CharCount < 0)
677  return std::error_code(errno, std::generic_category());
678 
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());
682  }
683  ResultPath.set_size(static_cast<size_t>(CharCount));
684 #endif
685  return std::error_code();
686 }
687 
688 } // end namespace fs
689 
690 namespace path {
691 
693  if (char *RequestedDir = getenv("HOME")) {
694  result.clear();
695  result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
696  return true;
697  }
698 
699  return false;
700 }
701 
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);
709  if (ConfLen > 0) {
710  do {
711  Result.resize(ConfLen);
712  ConfLen = confstr(ConfName, Result.data(), Result.size());
713  } while (ConfLen > 0 && ConfLen != Result.size());
714 
715  if (ConfLen > 0) {
716  assert(Result.back() == 0);
717  Result.pop_back();
718  return true;
719  }
720 
721  Result.clear();
722  }
723  #endif
724  return false;
725 }
726 
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")) {
732  Result.clear();
733  Result.append(XdgCacheDir, XdgCacheDir + strlen(XdgCacheDir));
734  return true;
735  }
736 
737  // Try Darwin configuration query
738  if (getDarwinConfDir(false, Result))
739  return true;
740 
741  // Use "$HOME/.cache" if $HOME is available
742  if (home_directory(Result)) {
743  append(Result, ".cache");
744  return true;
745  }
746 
747  return false;
748 }
749 
750 static const char *getEnvTempDir() {
751  // Check whether the temporary directory is specified by an environment
752  // variable.
753  const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
754  for (const char *Env : EnvironmentVariables) {
755  if (const char *Dir = std::getenv(Env))
756  return Dir;
757  }
758 
759  return nullptr;
760 }
761 
762 static const char *getDefaultTempDir(bool ErasedOnReboot) {
763 #ifdef P_tmpdir
764  if ((bool)P_tmpdir)
765  return P_tmpdir;
766 #endif
767 
768  if (ErasedOnReboot)
769  return "/tmp";
770  return "/var/tmp";
771 }
772 
773 void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
774  Result.clear();
775 
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));
780  return;
781  }
782  }
783 
784  if (getDarwinConfDir(ErasedOnReboot, Result))
785  return;
786 
787  const char *RequestedDir = getDefaultTempDir(ErasedOnReboot);
788  Result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
789 }
790 
791 } // end namespace path
792 
793 } // end namespace sys
794 } // end namespace llvm
F_Append - When opening a file, if it already exists append to the existing file instead of returning...
Definition: FileSystem.h:634
bool can_execute(const Twine &Path)
Can we execute this file?
Represents either an error or a value T.
Definition: ErrorOr.h:68
size_t capacity() const
Return the total number of elements in the currently allocated buffer.
Definition: SmallVector.h:139
SI Whole Quad Mode
std::error_code openFileForRead(const Twine &Name, int &ResultFD, SmallVectorImpl< char > *RealPath=nullptr)
F_Excl - When opening a file, this flag makes raw_fd_ostream report an error if the file already exis...
Definition: FileSystem.h:629
UniqueID getUniqueID() const
interleaved access
std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time)
Set the file modification and access time.
opt Optimize addressing mode
std::error_code current_path(SmallVectorImpl< char > &result)
Get the current path.
void reserve(size_type N)
Definition: SmallVector.h:377
file_status - Represents the result of a call to stat and friends.
Definition: FileSystem.h:142
LLVM_ATTRIBUTE_ALWAYS_INLINE TimePoint< std::chrono::seconds > toTimePoint(std::time_t T)
Convert a std::time_t to a TimePoint.
Definition: Chrono.h:44
bool status_known(file_status s)
Is status available?
Definition: Path.cpp:944
struct timespec toTimeSpec(TimePoint<> TP)
Convert a time point to struct timespec.
Definition: Unix.h:84
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:448
std::string str() const
Return the twine contents as a std::string.
Definition: Twine.cpp:17
struct fuzzer::@269 Flags
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)
Is path absolute?
Definition: Path.cpp:686
May access map via data and modify it. Written to path.
Definition: FileSystem.h:689
May only access map via const_data as read only.
Definition: FileSystem.h:688
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:641
static GCRegistry::Add< OcamlGC > B("ocaml","ocaml 3.10-compatible GC")
iterator begin() const
Definition: StringRef.h:103
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...
#define P(N)
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:395
The instances of the Type class are immutable: once they are created, they are never changed...
Definition: Type.h:45
static char * argv0
LLVM_ATTRIBUTE_ALWAYS_INLINE iterator begin()
Definition: SmallVector.h:115
std::error_code directory_iterator_construct(DirIterState &, StringRef)
TimePoint getLastAccessedTime() const
uint32_t Offset
std::error_code resize_file(int FD, uint64_t Size)
Resize path to size.
struct timeval toTimeVal(TimePoint< std::chrono::microseconds > TP)
Convert a time point to struct timeval.
Definition: Unix.h:94
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 append(in_iter in_start, in_iter in_end)
Add the specified range to the end of the SmallVector.
Definition: SmallVector.h:392
#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.
ErrorOr< space_info > disk_space(const Twine &Path)
Get disk space usage information.
void set_size(size_type N)
Set the array size to N, which the current array must have enough capacity for.
Definition: SmallVector.h:668
std::error_code directory_iterator_destruct(DirIterState &)
pointer data()
Return a pointer to the vector's buffer, even if empty().
Definition: SmallVector.h:142
file_type
An enumeration for the file system's view of the type.
Definition: FileSystem.h:55
LLVM_ATTRIBUTE_ALWAYS_INLINE size_type size() const
Definition: SmallVector.h:135
TimePoint getLastModificationTime() const
std::error_code create_directory(const Twine &path, bool IgnoreExisting=true, perms Perms=owner_all|group_all)
Create the directory in path.
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's represent the same thing?
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 char * name
bool home_directory(SmallVectorImpl< char > &result)
Get the user'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:47
std::error_code status(const Twine &path, file_status &result)
Get file status as if by POSIX stat().
bool exists(file_status status)
Does file exist?
Definition: Path.cpp:940
static GCRegistry::Add< ErlangGC > A("erlang","erlang-compatible garbage collector")
void resize(size_type N)
Definition: SmallVector.h:352
std::error_code openFileForWrite(const Twine &Name, int &ResultFD, OpenFlags Flags, unsigned Mode=0666)