1//===- llvm/Support/Unix/Path.inc - Unix Path Implementation ----*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the Unix specific implementation of the Path API.
10//
11//===----------------------------------------------------------------------===//
12
13//===----------------------------------------------------------------------===//
14//=== WARNING: Implementation here must contain only generic UNIX code that
15//=== is guaranteed to work on *all* UNIX variants.
16//===----------------------------------------------------------------------===//
17
18#include "Unix.h"
19#include <limits.h>
20#include <stdio.h>
21#include <sys/stat.h>
22#include <fcntl.h>
23#ifdef HAVE_UNISTD_H
24#include <unistd.h>
25#endif
26#ifdef HAVE_SYS_MMAN_H
27#include <sys/mman.h>
28#endif
29
30#include <dirent.h>
31#include <pwd.h>
32
33#ifdef __APPLE__
34#include <copyfile.h>
35#include <mach-o/dyld.h>
36#include <sys/attr.h>
37#if __has_include(<sys/clonefile.h>)
38#include <sys/clonefile.h>
39#endif
40#elif defined(__FreeBSD__)
41#include <osreldate.h>
42#if __FreeBSD_version >= 1300057
43#include <sys/auxv.h>
44#else
45#include <machine/elf.h>
46extern char **environ;
47#endif
48#elif defined(__DragonFly__)
49#include <sys/mount.h>
50#elif defined(__MVS__)
51#include "llvm/Support/AutoConvert.h"
52#include <sys/ps.h>
53#endif
54
55// Both stdio.h and cstdio are included via different paths and
56// stdcxx's cstdio doesn't include stdio.h, so it doesn't #undef the macros
57// either.
58#undef ferror
59#undef feof
60
61#if !defined(PATH_MAX)
62// For GNU Hurd
63#if defined(__GNU__)
64#define PATH_MAX 4096
65#elif defined(__MVS__)
66#define PATH_MAX _XOPEN_PATH_MAX
67#endif
68#endif
69
70#include <sys/types.h>
71#if !defined(__APPLE__) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && \
72 !defined(__linux__) && !defined(__FreeBSD_kernel__) && !defined(_AIX) && \
73 !defined(__managarm__)
74#include <sys/statvfs.h>
75#define STATVFS statvfs
76#define FSTATVFS fstatvfs
77#define STATVFS_F_FRSIZE(vfs) vfs.f_frsize
78#else
79#if defined(__OpenBSD__) || defined(__FreeBSD__)
80#include <sys/mount.h>
81#include <sys/param.h>
82#elif defined(__linux__) || defined(__managarm__)
83#if defined(HAVE_LINUX_MAGIC_H)
84#include <linux/magic.h>
85#else
86#if defined(HAVE_LINUX_NFS_FS_H)
87#include <linux/nfs_fs.h>
88#endif
89#if defined(HAVE_LINUX_SMB_H)
90#include <linux/smb.h>
91#endif
92#endif
93#include <sys/vfs.h>
94#elif defined(_AIX)
95#include <sys/statfs.h>
96
97// <sys/vmount.h> depends on `uint` to be a typedef from <sys/types.h> to
98// `uint_t`; however, <sys/types.h> does not always declare `uint`. We provide
99// the typedef prior to including <sys/vmount.h> to work around this issue.
100typedef uint_t uint;
101#include <sys/vmount.h>
102#else
103#include <sys/mount.h>
104#endif
105#define STATVFS statfs
106#define FSTATVFS fstatfs
107#define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
108#endif
109
110#if defined(__NetBSD__) || defined(__DragonFly__) || defined(__GNU__) || \
111 defined(__MVS__)
112#define STATVFS_F_FLAG(vfs) (vfs).f_flag
113#else
114#define STATVFS_F_FLAG(vfs) (vfs).f_flags
115#endif
116
117using namespace llvm;
118
119namespace llvm {
120namespace sys {
121namespace fs {
122
123const file_t kInvalidFile = -1;
124
125#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
126 defined(__FreeBSD_kernel__) || defined(__linux__) || \
127 defined(__CYGWIN__) || defined(__DragonFly__) || defined(_AIX) || \
128 defined(__GNU__) || \
129 (defined(__sun__) && defined(__svr4__) || defined(__HAIKU__)) || \
130 defined(__managarm__)
131static int test_dir(char ret[PATH_MAX], const char *dir, const char *bin) {
132 struct stat sb;
133 char fullpath[PATH_MAX];
134
135 int chars = snprintf(s: fullpath, PATH_MAX, format: "%s/%s", dir, bin);
136 // We cannot write PATH_MAX characters because the string will be terminated
137 // with a null character. Fail if truncation happened.
138 if (chars >= PATH_MAX)
139 return 1;
140 if (!realpath(name: fullpath, resolved: ret))
141 return 1;
142 if (stat(file: fullpath, buf: &sb) != 0)
143 return 1;
144
145 return 0;
146}
147
148static char *getprogpath(char ret[PATH_MAX], const char *bin) {
149 if (bin == nullptr)
150 return nullptr;
151
152 /* First approach: absolute path. */
153 if (bin[0] == '/') {
154 if (test_dir(ret, dir: "/", bin) == 0)
155 return ret;
156 return nullptr;
157 }
158
159 /* Second approach: relative path. */
160 if (strchr(s: bin, c: '/')) {
161 char cwd[PATH_MAX];
162 if (!getcwd(buf: cwd, PATH_MAX))
163 return nullptr;
164 if (test_dir(ret, dir: cwd, bin) == 0)
165 return ret;
166 return nullptr;
167 }
168
169 /* Third approach: $PATH */
170 char *pv;
171 if ((pv = getenv(name: "PATH")) == nullptr)
172 return nullptr;
173 char *s = strdup(s: pv);
174 if (!s)
175 return nullptr;
176 char *state;
177 for (char *t = strtok_r(s: s, delim: ":", save_ptr: &state); t != nullptr;
178 t = strtok_r(s: nullptr, delim: ":", save_ptr: &state)) {
179 if (test_dir(ret, dir: t, bin) == 0) {
180 free(ptr: s);
181 return ret;
182 }
183 }
184 free(ptr: s);
185 return nullptr;
186}
187#endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
188
189/// GetMainExecutable - Return the path to the main executable, given the
190/// value of argv[0] from program startup.
191std::string getMainExecutable(const char *argv0, void *MainAddr) {
192#if defined(__APPLE__)
193 // On OS X the executable path is saved to the stack by dyld. Reading it
194 // from there is much faster than calling dladdr, especially for large
195 // binaries with symbols.
196 char exe_path[PATH_MAX];
197 uint32_t size = sizeof(exe_path);
198 if (_NSGetExecutablePath(exe_path, &size) == 0) {
199 char link_path[PATH_MAX];
200 if (realpath(exe_path, link_path))
201 return link_path;
202 }
203#elif defined(__FreeBSD__)
204 // On FreeBSD if the exec path specified in ELF auxiliary vectors is
205 // preferred, if available. /proc/curproc/file and the KERN_PROC_PATHNAME
206 // sysctl may not return the desired path if there are multiple hardlinks
207 // to the file.
208 char exe_path[PATH_MAX];
209#if __FreeBSD_version >= 1300057
210 if (elf_aux_info(AT_EXECPATH, exe_path, sizeof(exe_path)) == 0) {
211 char link_path[PATH_MAX];
212 if (realpath(exe_path, link_path))
213 return link_path;
214 }
215#else
216 // elf_aux_info(AT_EXECPATH, ... is not available in all supported versions,
217 // fall back to finding the ELF auxiliary vectors after the process's
218 // environment.
219 char **p = ::environ;
220 while (*p++ != 0)
221 ;
222 // Iterate through auxiliary vectors for AT_EXECPATH.
223 for (Elf_Auxinfo *aux = (Elf_Auxinfo *)p; aux->a_type != AT_NULL; aux++) {
224 if (aux->a_type == AT_EXECPATH) {
225 char link_path[PATH_MAX];
226 if (realpath((char *)aux->a_un.a_ptr, link_path))
227 return link_path;
228 }
229 }
230#endif
231 // Fall back to argv[0] if auxiliary vectors are not available.
232 if (getprogpath(exe_path, argv0) != NULL)
233 return exe_path;
234#elif defined(_AIX) || defined(__DragonFly__) || defined(__FreeBSD_kernel__) || \
235 defined(__NetBSD__)
236 const char *curproc = "/proc/curproc/file";
237 char exe_path[PATH_MAX];
238 if (sys::fs::exists(curproc)) {
239 ssize_t len = readlink(curproc, exe_path, sizeof(exe_path));
240 if (len > 0) {
241 // Null terminate the string for realpath. readlink never null
242 // terminates its output.
243 len = std::min(len, ssize_t(sizeof(exe_path) - 1));
244 exe_path[len] = '\0';
245 return exe_path;
246 }
247 }
248 // If we don't have procfs mounted, fall back to argv[0]
249 if (getprogpath(exe_path, argv0) != NULL)
250 return exe_path;
251#elif defined(__linux__) || defined(__CYGWIN__) || defined(__gnu_hurd__) || \
252 defined(__managarm__)
253 char exe_path[PATH_MAX];
254 const char *aPath = "/proc/self/exe";
255 if (sys::fs::exists(Path: aPath)) {
256 // /proc is not always mounted under Linux (chroot for example).
257 ssize_t len = readlink(path: aPath, buf: exe_path, len: sizeof(exe_path));
258 if (len < 0)
259 return "";
260
261 // Null terminate the string for realpath. readlink never null
262 // terminates its output.
263 len = std::min(a: len, b: ssize_t(sizeof(exe_path) - 1));
264 exe_path[len] = '\0';
265
266 // On Linux, /proc/self/exe always looks through symlinks. However, on
267 // GNU/Hurd, /proc/self/exe is a symlink to the path that was used to start
268 // the program, and not the eventual binary file. Therefore, call realpath
269 // so this behaves the same on all platforms.
270#if _POSIX_VERSION >= 200112 || defined(__GLIBC__)
271 if (char *real_path = realpath(name: exe_path, resolved: nullptr)) {
272 std::string ret = std::string(real_path);
273 free(ptr: real_path);
274 return ret;
275 }
276#else
277 char real_path[PATH_MAX];
278 if (realpath(exe_path, real_path))
279 return std::string(real_path);
280#endif
281 }
282 // Fall back to the classical detection.
283 if (getprogpath(ret: exe_path, bin: argv0))
284 return exe_path;
285#elif defined(__OpenBSD__) || defined(__HAIKU__)
286 char exe_path[PATH_MAX];
287 // argv[0] only
288 if (getprogpath(exe_path, argv0) != NULL)
289 return exe_path;
290#elif defined(__sun__) && defined(__svr4__)
291 char exe_path[PATH_MAX];
292 const char *aPath = "/proc/self/execname";
293 if (sys::fs::exists(aPath)) {
294 int fd = open(aPath, O_RDONLY);
295 if (fd == -1)
296 return "";
297 if (read(fd, exe_path, sizeof(exe_path)) < 0)
298 return "";
299 return exe_path;
300 }
301 // Fall back to the classical detection.
302 if (getprogpath(exe_path, argv0) != NULL)
303 return exe_path;
304#elif defined(__MVS__)
305 int token = 0;
306 W_PSPROC buf;
307 char exe_path[PS_PATHBLEN];
308 pid_t pid = getpid();
309
310 memset(&buf, 0, sizeof(buf));
311 buf.ps_pathptr = exe_path;
312 buf.ps_pathlen = sizeof(exe_path);
313
314 while (true) {
315 if ((token = w_getpsent(token, &buf, sizeof(buf))) <= 0)
316 break;
317 if (buf.ps_pid != pid)
318 continue;
319 char real_path[PATH_MAX];
320 if (realpath(exe_path, real_path))
321 return std::string(real_path);
322 break; // Found entry, but realpath failed.
323 }
324#elif defined(HAVE_DLOPEN)
325 // Use dladdr to get executable path if available.
326 Dl_info DLInfo;
327 int err = dladdr(MainAddr, &DLInfo);
328 if (err == 0)
329 return "";
330
331 // If the filename is a symlink, we need to resolve and return the location of
332 // the actual executable.
333 char link_path[PATH_MAX];
334 if (realpath(DLInfo.dli_fname, link_path))
335 return link_path;
336#else
337#error GetMainExecutable is not implemented on this host yet.
338#endif
339 return "";
340}
341
342TimePoint<> basic_file_status::getLastAccessedTime() const {
343 return toTimePoint(T: fs_st_atime, nsec: fs_st_atime_nsec);
344}
345
346TimePoint<> basic_file_status::getLastModificationTime() const {
347 return toTimePoint(T: fs_st_mtime, nsec: fs_st_mtime_nsec);
348}
349
350UniqueID file_status::getUniqueID() const {
351 return UniqueID(fs_st_dev, fs_st_ino);
352}
353
354uint32_t file_status::getLinkCount() const { return fs_st_nlinks; }
355
356ErrorOr<space_info> disk_space(const Twine &Path) {
357 struct STATVFS Vfs;
358 if (::STATVFS(file: const_cast<char *>(Path.str().c_str()), buf: &Vfs))
359 return errnoAsErrorCode();
360 auto FrSize = STATVFS_F_FRSIZE(Vfs);
361 space_info SpaceInfo;
362 SpaceInfo.capacity = static_cast<uint64_t>(Vfs.f_blocks) * FrSize;
363 SpaceInfo.free = static_cast<uint64_t>(Vfs.f_bfree) * FrSize;
364 SpaceInfo.available = static_cast<uint64_t>(Vfs.f_bavail) * FrSize;
365 return SpaceInfo;
366}
367
368std::error_code current_path(SmallVectorImpl<char> &result) {
369 result.clear();
370
371 const char *pwd = ::getenv(name: "PWD");
372 llvm::sys::fs::file_status PWDStatus, DotStatus;
373 if (pwd && llvm::sys::path::is_absolute(path: pwd) &&
374 !llvm::sys::fs::status(path: pwd, result&: PWDStatus) &&
375 !llvm::sys::fs::status(path: ".", result&: DotStatus) &&
376 PWDStatus.getUniqueID() == DotStatus.getUniqueID()) {
377 result.append(in_start: pwd, in_end: pwd + strlen(s: pwd));
378 return std::error_code();
379 }
380
381 result.resize_for_overwrite(PATH_MAX);
382
383 while (true) {
384 if (::getcwd(buf: result.data(), size: result.size()) == nullptr) {
385 // See if there was a real error.
386 if (errno != ENOMEM) {
387 result.clear();
388 return errnoAsErrorCode();
389 }
390 // Otherwise there just wasn't enough space.
391 result.resize_for_overwrite(N: result.capacity() * 2);
392 } else {
393 break;
394 }
395 }
396
397 result.truncate(N: strlen(s: result.data()));
398 return std::error_code();
399}
400
401std::error_code set_current_path(const Twine &path) {
402 SmallString<128> path_storage;
403 StringRef p = path.toNullTerminatedStringRef(Out&: path_storage);
404
405 if (::chdir(path: p.begin()) == -1)
406 return errnoAsErrorCode();
407
408 return std::error_code();
409}
410
411std::error_code create_directory(const Twine &path, bool IgnoreExisting,
412 perms Perms) {
413 SmallString<128> path_storage;
414 StringRef p = path.toNullTerminatedStringRef(Out&: path_storage);
415
416 if (::mkdir(path: p.begin(), mode: Perms) == -1) {
417 if (errno != EEXIST || !IgnoreExisting)
418 return errnoAsErrorCode();
419 }
420
421 return std::error_code();
422}
423
424// Note that we are using symbolic link because hard links are not supported by
425// all filesystems (SMB doesn't).
426std::error_code create_link(const Twine &to, const Twine &from) {
427 // Get arguments.
428 SmallString<128> from_storage;
429 SmallString<128> to_storage;
430 StringRef f = from.toNullTerminatedStringRef(Out&: from_storage);
431 StringRef t = to.toNullTerminatedStringRef(Out&: to_storage);
432
433 if (::symlink(from: t.begin(), to: f.begin()) == -1)
434 return errnoAsErrorCode();
435
436 return std::error_code();
437}
438
439std::error_code create_hard_link(const Twine &to, const Twine &from) {
440 // Get arguments.
441 SmallString<128> from_storage;
442 SmallString<128> to_storage;
443 StringRef f = from.toNullTerminatedStringRef(Out&: from_storage);
444 StringRef t = to.toNullTerminatedStringRef(Out&: to_storage);
445
446 if (::link(from: t.begin(), to: f.begin()) == -1)
447 return errnoAsErrorCode();
448
449 return std::error_code();
450}
451
452std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
453 SmallString<128> path_storage;
454 StringRef p = path.toNullTerminatedStringRef(Out&: path_storage);
455
456 struct stat buf;
457 if (lstat(file: p.begin(), buf: &buf) != 0) {
458 if (errno != ENOENT || !IgnoreNonExisting)
459 return errnoAsErrorCode();
460 return std::error_code();
461 }
462
463 // Note: this check catches strange situations. In all cases, LLVM should
464 // only be involved in the creation and deletion of regular files. This
465 // check ensures that what we're trying to erase is a regular file. It
466 // effectively prevents LLVM from erasing things like /dev/null, any block
467 // special file, or other things that aren't "regular" files.
468 if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode))
469 return make_error_code(E: errc::operation_not_permitted);
470
471 if (::remove(filename: p.begin()) == -1) {
472 if (errno != ENOENT || !IgnoreNonExisting)
473 return errnoAsErrorCode();
474 }
475
476 return std::error_code();
477}
478
479static bool is_local_impl(struct STATVFS &Vfs) {
480#if defined(__linux__) || defined(__GNU__) || defined(__managarm__)
481#ifndef NFS_SUPER_MAGIC
482#define NFS_SUPER_MAGIC 0x6969
483#endif
484#ifndef SMB_SUPER_MAGIC
485#define SMB_SUPER_MAGIC 0x517B
486#endif
487#ifndef CIFS_MAGIC_NUMBER
488#define CIFS_MAGIC_NUMBER 0xFF534D42
489#endif
490#if defined(__GNU__) && ((__GLIBC__ < 2) || ((__GLIBC__ == 2) && (__GLIBC_MINOR__ < 39)))
491 switch ((uint32_t)Vfs.__f_type) {
492#else
493 switch ((uint32_t)Vfs.f_type) {
494#endif
495 case NFS_SUPER_MAGIC:
496 case SMB_SUPER_MAGIC:
497 case CIFS_MAGIC_NUMBER:
498 return false;
499 default:
500 return true;
501 }
502#elif defined(__CYGWIN__)
503 // Cygwin doesn't expose this information; would need to use Win32 API.
504 return false;
505#elif defined(__Fuchsia__)
506 // Fuchsia doesn't yet support remote filesystem mounts.
507 return true;
508#elif defined(__EMSCRIPTEN__)
509 // Emscripten doesn't currently support remote filesystem mounts.
510 return true;
511#elif defined(__HAIKU__)
512 // Haiku doesn't expose this information.
513 return false;
514#elif defined(__sun)
515 // statvfs::f_basetype contains a null-terminated FSType name of the mounted
516 // target
517 StringRef fstype(Vfs.f_basetype);
518 // NFS is the only non-local fstype??
519 return fstype != "nfs";
520#elif defined(_AIX)
521 // Call mntctl; try more than twice in case of timing issues with a concurrent
522 // mount.
523 int Ret;
524 size_t BufSize = 2048u;
525 std::unique_ptr<char[]> Buf;
526 int Tries = 3;
527 while (Tries--) {
528 Buf = std::make_unique<char[]>(BufSize);
529 Ret = mntctl(MCTL_QUERY, BufSize, Buf.get());
530 if (Ret != 0)
531 break;
532 BufSize = *reinterpret_cast<unsigned int *>(Buf.get());
533 Buf.reset();
534 }
535
536 if (Ret == -1)
537 // There was an error; "remote" is the conservative answer.
538 return false;
539
540 // Look for the correct vmount entry.
541 char *CurObjPtr = Buf.get();
542 while (Ret--) {
543 struct vmount *Vp = reinterpret_cast<struct vmount *>(CurObjPtr);
544 static_assert(sizeof(Vfs.f_fsid) == sizeof(Vp->vmt_fsid),
545 "fsid length mismatch");
546 if (memcmp(&Vfs.f_fsid, &Vp->vmt_fsid, sizeof Vfs.f_fsid) == 0)
547 return (Vp->vmt_flags & MNT_REMOTE) == 0;
548
549 CurObjPtr += Vp->vmt_length;
550 }
551
552 // vmount entry not found; "remote" is the conservative answer.
553 return false;
554#elif defined(__MVS__)
555 // The file system can have an arbitrary structure on z/OS; must go with the
556 // conservative answer.
557 return false;
558#else
559 return !!(STATVFS_F_FLAG(Vfs) & MNT_LOCAL);
560#endif
561}
562
563std::error_code is_local(const Twine &Path, bool &Result) {
564 struct STATVFS Vfs;
565 if (::STATVFS(file: const_cast<char *>(Path.str().c_str()), buf: &Vfs))
566 return errnoAsErrorCode();
567
568 Result = is_local_impl(Vfs);
569 return std::error_code();
570}
571
572std::error_code is_local(int FD, bool &Result) {
573 struct STATVFS Vfs;
574 if (::FSTATVFS(fildes: FD, buf: &Vfs))
575 return errnoAsErrorCode();
576
577 Result = is_local_impl(Vfs);
578 return std::error_code();
579}
580
581std::error_code rename(const Twine &from, const Twine &to) {
582 // Get arguments.
583 SmallString<128> from_storage;
584 SmallString<128> to_storage;
585 StringRef f = from.toNullTerminatedStringRef(Out&: from_storage);
586 StringRef t = to.toNullTerminatedStringRef(Out&: to_storage);
587
588 if (::rename(old: f.begin(), new: t.begin()) == -1)
589 return errnoAsErrorCode();
590
591 return std::error_code();
592}
593
594std::error_code resize_file(int FD, uint64_t Size) {
595 // Use ftruncate as a fallback. It may or may not allocate space. At least on
596 // OS X with HFS+ it does.
597 if (::ftruncate(fd: FD, length: Size) == -1)
598 return errnoAsErrorCode();
599
600 return std::error_code();
601}
602
603static int convertAccessMode(AccessMode Mode) {
604 switch (Mode) {
605 case AccessMode::Exist:
606 return F_OK;
607 case AccessMode::Write:
608 return W_OK;
609 case AccessMode::Execute:
610 return R_OK | X_OK; // scripts also need R_OK.
611 }
612 llvm_unreachable("invalid enum");
613}
614
615std::error_code access(const Twine &Path, AccessMode Mode) {
616 SmallString<128> PathStorage;
617 StringRef P = Path.toNullTerminatedStringRef(Out&: PathStorage);
618
619 if (::access(name: P.begin(), type: convertAccessMode(Mode)) == -1)
620 return errnoAsErrorCode();
621
622 if (Mode == AccessMode::Execute) {
623 // Don't say that directories are executable.
624 struct stat buf;
625 if (0 != stat(file: P.begin(), buf: &buf))
626 return errc::permission_denied;
627 if (!S_ISREG(buf.st_mode))
628 return errc::permission_denied;
629 }
630
631 return std::error_code();
632}
633
634bool can_execute(const Twine &Path) {
635 return !access(Path, Mode: AccessMode::Execute);
636}
637
638bool equivalent(file_status A, file_status B) {
639 assert(status_known(A) && status_known(B));
640 return A.fs_st_dev == B.fs_st_dev && A.fs_st_ino == B.fs_st_ino;
641}
642
643std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
644 file_status fsA, fsB;
645 if (std::error_code ec = status(path: A, result&: fsA))
646 return ec;
647 if (std::error_code ec = status(path: B, result&: fsB))
648 return ec;
649 result = equivalent(A: fsA, B: fsB);
650 return std::error_code();
651}
652
653static void expandTildeExpr(SmallVectorImpl<char> &Path) {
654 StringRef PathStr(Path.begin(), Path.size());
655 if (PathStr.empty() || !PathStr.starts_with(Prefix: "~"))
656 return;
657
658 PathStr = PathStr.drop_front();
659 StringRef Expr =
660 PathStr.take_until(F: [](char c) { return path::is_separator(value: c); });
661 StringRef Remainder = PathStr.substr(Start: Expr.size() + 1);
662 SmallString<128> Storage;
663 if (Expr.empty()) {
664 // This is just ~/..., resolve it to the current user's home dir.
665 if (!path::home_directory(result&: Storage)) {
666 // For some reason we couldn't get the home directory. Just exit.
667 return;
668 }
669
670 // Overwrite the first character and insert the rest.
671 Path[0] = Storage[0];
672 Path.insert(I: Path.begin() + 1, From: Storage.begin() + 1, To: Storage.end());
673 return;
674 }
675
676 // This is a string of the form ~username/, look up this user's entry in the
677 // password database.
678 std::unique_ptr<char[]> Buf;
679 long BufSize = sysconf(_SC_GETPW_R_SIZE_MAX);
680 if (BufSize <= 0)
681 BufSize = 16384;
682 Buf = std::make_unique<char[]>(num: BufSize);
683 struct passwd Pwd;
684 std::string User = Expr.str();
685 struct passwd *Entry = nullptr;
686 getpwnam_r(name: User.c_str(), resultbuf: &Pwd, buffer: Buf.get(), buflen: BufSize, result: &Entry);
687
688 if (!Entry || !Entry->pw_dir) {
689 // Unable to look up the entry, just return back the original path.
690 return;
691 }
692
693 Storage = Remainder;
694 Path.clear();
695 Path.append(in_start: Entry->pw_dir, in_end: Entry->pw_dir + strlen(s: Entry->pw_dir));
696 llvm::sys::path::append(path&: Path, a: Storage);
697}
698
699void expand_tilde(const Twine &path, SmallVectorImpl<char> &dest) {
700 dest.clear();
701 if (path.isTriviallyEmpty())
702 return;
703
704 path.toVector(Out&: dest);
705 expandTildeExpr(Path&: dest);
706}
707
708static file_type typeForMode(mode_t Mode) {
709 if (S_ISDIR(Mode))
710 return file_type::directory_file;
711 else if (S_ISREG(Mode))
712 return file_type::regular_file;
713 else if (S_ISBLK(Mode))
714 return file_type::block_file;
715 else if (S_ISCHR(Mode))
716 return file_type::character_file;
717 else if (S_ISFIFO(Mode))
718 return file_type::fifo_file;
719 else if (S_ISSOCK(Mode))
720 return file_type::socket_file;
721 else if (S_ISLNK(Mode))
722 return file_type::symlink_file;
723 return file_type::type_unknown;
724}
725
726static std::error_code fillStatus(int StatRet, const struct stat &Status,
727 file_status &Result) {
728 if (StatRet != 0) {
729 std::error_code EC = errnoAsErrorCode();
730 if (EC == errc::no_such_file_or_directory)
731 Result = file_status(file_type::file_not_found);
732 else
733 Result = file_status(file_type::status_error);
734 return EC;
735 }
736
737 uint32_t atime_nsec, mtime_nsec;
738#if defined(HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC)
739 atime_nsec = Status.st_atimespec.tv_nsec;
740 mtime_nsec = Status.st_mtimespec.tv_nsec;
741#elif defined(HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC)
742 atime_nsec = Status.st_atim.tv_nsec;
743 mtime_nsec = Status.st_mtim.tv_nsec;
744#else
745 atime_nsec = mtime_nsec = 0;
746#endif
747
748 perms Perms = static_cast<perms>(Status.st_mode) & all_perms;
749 Result = file_status(typeForMode(Mode: Status.st_mode), Perms, Status.st_dev,
750 Status.st_nlink, Status.st_ino, Status.st_atime,
751 atime_nsec, Status.st_mtime, mtime_nsec, Status.st_uid,
752 Status.st_gid, Status.st_size);
753
754 return std::error_code();
755}
756
757std::error_code status(const Twine &Path, file_status &Result, bool Follow) {
758 SmallString<128> PathStorage;
759 StringRef P = Path.toNullTerminatedStringRef(Out&: PathStorage);
760
761 struct stat Status;
762 int StatRet = (Follow ? ::stat : ::lstat)(P.begin(), &Status);
763 return fillStatus(StatRet, Status, Result);
764}
765
766std::error_code status(int FD, file_status &Result) {
767 struct stat Status;
768 int StatRet = ::fstat(fd: FD, buf: &Status);
769 return fillStatus(StatRet, Status, Result);
770}
771
772unsigned getUmask() {
773 // Chose arbitary new mask and reset the umask to the old mask.
774 // umask(2) never fails so ignore the return of the second call.
775 unsigned Mask = ::umask(mask: 0);
776 (void)::umask(mask: Mask);
777 return Mask;
778}
779
780std::error_code setPermissions(const Twine &Path, perms Permissions) {
781 SmallString<128> PathStorage;
782 StringRef P = Path.toNullTerminatedStringRef(Out&: PathStorage);
783
784 if (::chmod(file: P.begin(), mode: Permissions))
785 return errnoAsErrorCode();
786 return std::error_code();
787}
788
789std::error_code setPermissions(int FD, perms Permissions) {
790 if (::fchmod(fd: FD, mode: Permissions))
791 return errnoAsErrorCode();
792 return std::error_code();
793}
794
795std::error_code setLastAccessAndModificationTime(int FD, TimePoint<> AccessTime,
796 TimePoint<> ModificationTime) {
797#if defined(HAVE_FUTIMENS)
798 timespec Times[2];
799 Times[0] = sys::toTimeSpec(TP: AccessTime);
800 Times[1] = sys::toTimeSpec(TP: ModificationTime);
801 if (::futimens(fd: FD, times: Times))
802 return errnoAsErrorCode();
803 return std::error_code();
804#elif defined(HAVE_FUTIMES)
805 timeval Times[2];
806 Times[0] = sys::toTimeVal(
807 std::chrono::time_point_cast<std::chrono::microseconds>(AccessTime));
808 Times[1] =
809 sys::toTimeVal(std::chrono::time_point_cast<std::chrono::microseconds>(
810 ModificationTime));
811 if (::futimes(FD, Times))
812 return errnoAsErrorCode();
813 return std::error_code();
814#elif defined(__MVS__)
815 attrib_t Attr;
816 memset(&Attr, 0, sizeof(Attr));
817 Attr.att_atimechg = 1;
818 Attr.att_atime = sys::toTimeT(AccessTime);
819 Attr.att_mtimechg = 1;
820 Attr.att_mtime = sys::toTimeT(ModificationTime);
821 if (::__fchattr(FD, &Attr, sizeof(Attr)) != 0)
822 return errnoAsErrorCode();
823 return std::error_code();
824#else
825#warning Missing futimes() and futimens()
826 return make_error_code(errc::function_not_supported);
827#endif
828}
829
830std::error_code mapped_file_region::init(int FD, uint64_t Offset,
831 mapmode Mode) {
832 assert(Size != 0);
833
834 int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE;
835 int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE);
836#if defined(MAP_NORESERVE)
837 flags |= MAP_NORESERVE;
838#endif
839#if defined(__APPLE__)
840 //----------------------------------------------------------------------
841 // Newer versions of MacOSX have a flag that will allow us to read from
842 // binaries whose code signature is invalid without crashing by using
843 // the MAP_RESILIENT_CODESIGN flag. Also if a file from removable media
844 // is mapped we can avoid crashing and return zeroes to any pages we try
845 // to read if the media becomes unavailable by using the
846 // MAP_RESILIENT_MEDIA flag. These flags are only usable when mapping
847 // with PROT_READ, so take care not to specify them otherwise.
848 //----------------------------------------------------------------------
849 if (Mode == readonly) {
850#if defined(MAP_RESILIENT_CODESIGN)
851 flags |= MAP_RESILIENT_CODESIGN;
852#endif
853#if defined(MAP_RESILIENT_MEDIA)
854 flags |= MAP_RESILIENT_MEDIA;
855#endif
856 }
857#endif // #if defined (__APPLE__)
858
859 Mapping = ::mmap(addr: nullptr, len: Size, prot: prot, flags: flags, fd: FD, offset: Offset);
860 if (Mapping == MAP_FAILED)
861 return errnoAsErrorCode();
862 return std::error_code();
863}
864
865mapped_file_region::mapped_file_region(int fd, mapmode mode, size_t length,
866 uint64_t offset, std::error_code &ec)
867 : Size(length), Mode(mode) {
868 (void)Mode;
869 ec = init(FD: fd, Offset: offset, Mode: mode);
870 if (ec)
871 copyFrom(Copied: mapped_file_region());
872}
873
874void mapped_file_region::unmapImpl() {
875 if (Mapping)
876 ::munmap(addr: Mapping, len: Size);
877}
878
879void mapped_file_region::dontNeedImpl() {
880 assert(Mode == mapped_file_region::readonly);
881 if (!Mapping)
882 return;
883#if defined(__MVS__) || defined(_AIX)
884 // If we don't have madvise, or it isn't beneficial, treat this as a no-op.
885#elif defined(POSIX_MADV_DONTNEED)
886 ::posix_madvise(addr: Mapping, len: Size, POSIX_MADV_DONTNEED);
887#else
888 ::madvise(Mapping, Size, MADV_DONTNEED);
889#endif
890}
891
892int mapped_file_region::alignment() { return Process::getPageSizeEstimate(); }
893
894std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
895 StringRef path,
896 bool follow_symlinks) {
897 SmallString<128> path_null(path);
898 DIR *directory = ::opendir(name: path_null.c_str());
899 if (!directory)
900 return errnoAsErrorCode();
901
902 it.IterationHandle = reinterpret_cast<intptr_t>(directory);
903 // Add something for replace_filename to replace.
904 path::append(path&: path_null, a: ".");
905 it.CurrentEntry = directory_entry(path_null.str(), follow_symlinks);
906 return directory_iterator_increment(it);
907}
908
909std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
910 if (it.IterationHandle)
911 ::closedir(dirp: reinterpret_cast<DIR *>(it.IterationHandle));
912 it.IterationHandle = 0;
913 it.CurrentEntry = directory_entry();
914 return std::error_code();
915}
916
917static file_type direntType(dirent *Entry) {
918 // Most platforms provide the file type in the dirent: Linux/BSD/Mac.
919 // The DTTOIF macro lets us reuse our status -> type conversion.
920 // Note that while glibc provides a macro to see if this is supported,
921 // _DIRENT_HAVE_D_TYPE, it's not defined on BSD/Mac, so we test for the
922 // d_type-to-mode_t conversion macro instead.
923#if defined(DTTOIF)
924 return typeForMode(DTTOIF(Entry->d_type));
925#else
926 // Other platforms such as Solaris require a stat() to get the type.
927 return file_type::type_unknown;
928#endif
929}
930
931std::error_code detail::directory_iterator_increment(detail::DirIterState &It) {
932 errno = 0;
933 dirent *CurDir = ::readdir(dirp: reinterpret_cast<DIR *>(It.IterationHandle));
934 if (CurDir == nullptr && errno != 0) {
935 return errnoAsErrorCode();
936 } else if (CurDir != nullptr) {
937 StringRef Name(CurDir->d_name);
938 if ((Name.size() == 1 && Name[0] == '.') ||
939 (Name.size() == 2 && Name[0] == '.' && Name[1] == '.'))
940 return directory_iterator_increment(It);
941 It.CurrentEntry.replace_filename(Filename: Name, Type: direntType(Entry: CurDir));
942 } else {
943 return directory_iterator_destruct(it&: It);
944 }
945
946 return std::error_code();
947}
948
949ErrorOr<basic_file_status> directory_entry::status() const {
950 file_status s;
951 if (auto EC = fs::status(Path, Result&: s, Follow: FollowSymlinks))
952 return EC;
953 return s;
954}
955
956//
957// FreeBSD optionally provides /proc/self/fd, but it is incompatible with
958// Linux. The thing to use is realpath.
959//
960#if !defined(__FreeBSD__) && !defined(__OpenBSD__)
961#define TRY_PROC_SELF_FD
962#endif
963
964#if !defined(F_GETPATH) && defined(TRY_PROC_SELF_FD)
965static bool hasProcSelfFD() {
966 // If we have a /proc filesystem mounted, we can quickly establish the
967 // real name of the file with readlink
968 static const bool Result = (::access(name: "/proc/self/fd", R_OK) == 0);
969 return Result;
970}
971#endif
972
973static int nativeOpenFlags(CreationDisposition Disp, OpenFlags Flags,
974 FileAccess Access) {
975 int Result = 0;
976 if (Access == FA_Read)
977 Result |= O_RDONLY;
978 else if (Access == FA_Write)
979 Result |= O_WRONLY;
980 else if (Access == (FA_Read | FA_Write))
981 Result |= O_RDWR;
982
983 // This is for compatibility with old code that assumed OF_Append implied
984 // would open an existing file. See Windows/Path.inc for a longer comment.
985 if (Flags & OF_Append)
986 Disp = CD_OpenAlways;
987
988 if (Disp == CD_CreateNew) {
989 Result |= O_CREAT; // Create if it doesn't exist.
990 Result |= O_EXCL; // Fail if it does.
991 } else if (Disp == CD_CreateAlways) {
992 Result |= O_CREAT; // Create if it doesn't exist.
993 Result |= O_TRUNC; // Truncate if it does.
994 } else if (Disp == CD_OpenAlways) {
995 Result |= O_CREAT; // Create if it doesn't exist.
996 } else if (Disp == CD_OpenExisting) {
997 // Nothing special, just don't add O_CREAT and we get these semantics.
998 }
999
1000// Using append mode with z/OS UTF-8 auto-conversion results in EINVAL when
1001// calling write(). Instead we need to use lseek() to set offset to EOF after
1002// open().
1003#ifndef __MVS__
1004 if (Flags & OF_Append)
1005 Result |= O_APPEND;
1006#endif
1007
1008#ifdef O_CLOEXEC
1009 if (!(Flags & OF_ChildInherit))
1010 Result |= O_CLOEXEC;
1011#endif
1012
1013 return Result;
1014}
1015
1016std::error_code openFile(const Twine &Name, int &ResultFD,
1017 CreationDisposition Disp, FileAccess Access,
1018 OpenFlags Flags, unsigned Mode) {
1019 int OpenFlags = nativeOpenFlags(Disp, Flags, Access);
1020
1021 SmallString<128> Storage;
1022 StringRef P = Name.toNullTerminatedStringRef(Out&: Storage);
1023 // Call ::open in a lambda to avoid overload resolution in RetryAfterSignal
1024 // when open is overloaded, such as in Bionic.
1025 auto Open = [&]() { return ::open(file: P.begin(), oflag: OpenFlags, Mode); };
1026 if ((ResultFD = sys::RetryAfterSignal(Fail: -1, F: Open)) < 0)
1027 return errnoAsErrorCode();
1028#ifndef O_CLOEXEC
1029 if (!(Flags & OF_ChildInherit)) {
1030 int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC);
1031 (void)r;
1032 assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed");
1033 }
1034#endif
1035
1036#ifdef __MVS__
1037 /* Reason about auto-conversion and file tags. Setting the file tag only
1038 * applies if file is opened in write mode:
1039 *
1040 * Text file:
1041 * File exists File created
1042 * CD_CreateNew n/a conv: on
1043 * tag: set 1047
1044 * CD_CreateAlways conv: auto conv: on
1045 * tag: auto 1047 tag: set 1047
1046 * CD_OpenAlways conv: auto conv: on
1047 * tag: auto 1047 tag: set 1047
1048 * CD_OpenExisting conv: auto n/a
1049 * tag: unchanged
1050 *
1051 * Binary file:
1052 * File exists File created
1053 * CD_CreateNew n/a conv: off
1054 * tag: set binary
1055 * CD_CreateAlways conv: off conv: off
1056 * tag: auto binary tag: set binary
1057 * CD_OpenAlways conv: off conv: off
1058 * tag: auto binary tag: set binary
1059 * CD_OpenExisting conv: off n/a
1060 * tag: unchanged
1061 *
1062 * Actions:
1063 * conv: off -> auto-conversion is turned off
1064 * conv: on -> auto-conversion is turned on
1065 * conv: auto -> auto-conversion is turned on if the file is untagged
1066 * tag: set 1047 -> set the file tag to text encoded in 1047
1067 * tag: set binary -> set the file tag to binary
1068 * tag: auto 1047 -> set file tag to 1047 if not set
1069 * tag: auto binary -> set file tag to binary if not set
1070 * tag: unchanged -> do not care about the file tag
1071 *
1072 * It is not possible to distinguish between the cases "file exists" and
1073 * "file created". In the latter case, the file tag is not set and the file
1074 * size is zero. The decision table boils down to:
1075 *
1076 * the file tag is set if
1077 * - the file is opened for writing
1078 * - the create disposition is not equal to CD_OpenExisting
1079 * - the file tag is not set
1080 * - the file size is zero
1081 *
1082 * This only applies if the file is a regular file. E.g. enabling
1083 * auto-conversion for reading from /dev/null results in error EINVAL when
1084 * calling read().
1085 *
1086 * Using append mode with z/OS UTF-8 auto-conversion results in EINVAL when
1087 * calling write(). Instead we need to use lseek() to set offset to EOF after
1088 * open().
1089 */
1090 if ((Flags & OF_Append) && lseek(ResultFD, 0, SEEK_END) == -1)
1091 return errnoAsErrorCode();
1092 struct stat Stat;
1093 if (fstat(ResultFD, &Stat) == -1)
1094 return errnoAsErrorCode();
1095 if (S_ISREG(Stat.st_mode)) {
1096 bool DoSetTag = (Access & FA_Write) && (Disp != CD_OpenExisting) &&
1097 !Stat.st_tag.ft_txtflag && !Stat.st_tag.ft_ccsid &&
1098 Stat.st_size == 0;
1099 if (Flags & OF_Text) {
1100 if (auto EC = llvm::enableAutoConversion(ResultFD))
1101 return EC;
1102 if (DoSetTag) {
1103 if (auto EC = llvm::setzOSFileTag(ResultFD, CCSID_IBM_1047, true))
1104 return EC;
1105 }
1106 } else {
1107 if (auto EC = llvm::disableAutoConversion(ResultFD))
1108 return EC;
1109 if (DoSetTag) {
1110 if (auto EC = llvm::setzOSFileTag(ResultFD, FT_BINARY, false))
1111 return EC;
1112 }
1113 }
1114 }
1115#endif
1116
1117 return std::error_code();
1118}
1119
1120Expected<int> openNativeFile(const Twine &Name, CreationDisposition Disp,
1121 FileAccess Access, OpenFlags Flags,
1122 unsigned Mode) {
1123
1124 int FD;
1125 std::error_code EC = openFile(Name, ResultFD&: FD, Disp, Access, Flags, Mode);
1126 if (EC)
1127 return errorCodeToError(EC);
1128 return FD;
1129}
1130
1131std::error_code openFileForRead(const Twine &Name, int &ResultFD,
1132 OpenFlags Flags,
1133 SmallVectorImpl<char> *RealPath) {
1134 std::error_code EC =
1135 openFile(Name, ResultFD, Disp: CD_OpenExisting, Access: FA_Read, Flags, Mode: 0666);
1136 if (EC)
1137 return EC;
1138
1139 // Attempt to get the real name of the file, if the user asked
1140 if (!RealPath)
1141 return std::error_code();
1142 RealPath->clear();
1143#if defined(F_GETPATH)
1144 // When F_GETPATH is availble, it is the quickest way to get
1145 // the real path name.
1146 char Buffer[PATH_MAX];
1147 if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1)
1148 RealPath->append(Buffer, Buffer + strlen(Buffer));
1149#else
1150 char Buffer[PATH_MAX];
1151#if defined(TRY_PROC_SELF_FD)
1152 if (hasProcSelfFD()) {
1153 char ProcPath[64];
1154 snprintf(s: ProcPath, maxlen: sizeof(ProcPath), format: "/proc/self/fd/%d", ResultFD);
1155 ssize_t CharCount = ::readlink(path: ProcPath, buf: Buffer, len: sizeof(Buffer));
1156 if (CharCount > 0)
1157 RealPath->append(in_start: Buffer, in_end: Buffer + CharCount);
1158 } else {
1159#endif
1160 SmallString<128> Storage;
1161 StringRef P = Name.toNullTerminatedStringRef(Out&: Storage);
1162
1163 // Use ::realpath to get the real path name
1164 if (::realpath(name: P.begin(), resolved: Buffer) != nullptr)
1165 RealPath->append(in_start: Buffer, in_end: Buffer + strlen(s: Buffer));
1166#if defined(TRY_PROC_SELF_FD)
1167 }
1168#endif
1169#endif
1170 return std::error_code();
1171}
1172
1173Expected<file_t> openNativeFileForRead(const Twine &Name, OpenFlags Flags,
1174 SmallVectorImpl<char> *RealPath) {
1175 file_t ResultFD;
1176 std::error_code EC = openFileForRead(Name, ResultFD, Flags, RealPath);
1177 if (EC)
1178 return errorCodeToError(EC);
1179 return ResultFD;
1180}
1181
1182file_t getStdinHandle() { return 0; }
1183file_t getStdoutHandle() { return 1; }
1184file_t getStderrHandle() { return 2; }
1185
1186Expected<size_t> readNativeFile(file_t FD, MutableArrayRef<char> Buf) {
1187#if defined(__APPLE__)
1188 size_t Size = std::min<size_t>(Buf.size(), INT32_MAX);
1189#else
1190 size_t Size = Buf.size();
1191#endif
1192 ssize_t NumRead = sys::RetryAfterSignal(Fail: -1, F&: ::read, As: FD, As: Buf.data(), As: Size);
1193 if (ssize_t(NumRead) == -1)
1194 return errorCodeToError(EC: errnoAsErrorCode());
1195// The underlying operation on these platforms allow opening directories
1196// for reading in more cases than other platforms.
1197#if defined(__MVS__) || defined(_AIX)
1198 struct stat Status;
1199 if (fstat(FD, &Status) == -1)
1200 return errorCodeToError(errnoAsErrorCode());
1201 if (S_ISDIR(Status.st_mode))
1202 return errorCodeToError(make_error_code(errc::is_a_directory));
1203#endif
1204 return NumRead;
1205}
1206
1207Expected<size_t> readNativeFileSlice(file_t FD, MutableArrayRef<char> Buf,
1208 uint64_t Offset) {
1209#if defined(__APPLE__)
1210 size_t Size = std::min<size_t>(Buf.size(), INT32_MAX);
1211#else
1212 size_t Size = Buf.size();
1213#endif
1214#ifdef HAVE_PREAD
1215 ssize_t NumRead =
1216 sys::RetryAfterSignal(Fail: -1, F&: ::pread, As: FD, As: Buf.data(), As: Size, As: Offset);
1217#else
1218 if (lseek(FD, Offset, SEEK_SET) == -1)
1219 return errorCodeToError(errnoAsErrorCode());
1220 ssize_t NumRead = sys::RetryAfterSignal(-1, ::read, FD, Buf.data(), Size);
1221#endif
1222 if (NumRead == -1)
1223 return errorCodeToError(EC: errnoAsErrorCode());
1224 return NumRead;
1225}
1226
1227std::error_code tryLockFile(int FD, std::chrono::milliseconds Timeout) {
1228 auto Start = std::chrono::steady_clock::now();
1229 auto End = Start + Timeout;
1230 do {
1231 struct flock Lock;
1232 memset(s: &Lock, c: 0, n: sizeof(Lock));
1233 Lock.l_type = F_WRLCK;
1234 Lock.l_whence = SEEK_SET;
1235 Lock.l_start = 0;
1236 Lock.l_len = 0;
1237 if (::fcntl(fd: FD, F_SETLK, &Lock) != -1)
1238 return std::error_code();
1239 int Error = errno;
1240 if (Error != EACCES && Error != EAGAIN)
1241 return std::error_code(Error, std::generic_category());
1242 usleep(useconds: 1000);
1243 } while (std::chrono::steady_clock::now() < End);
1244 return make_error_code(E: errc::no_lock_available);
1245}
1246
1247std::error_code lockFile(int FD) {
1248 struct flock Lock;
1249 memset(s: &Lock, c: 0, n: sizeof(Lock));
1250 Lock.l_type = F_WRLCK;
1251 Lock.l_whence = SEEK_SET;
1252 Lock.l_start = 0;
1253 Lock.l_len = 0;
1254 if (::fcntl(fd: FD, F_SETLKW, &Lock) != -1)
1255 return std::error_code();
1256 return errnoAsErrorCode();
1257}
1258
1259std::error_code unlockFile(int FD) {
1260 struct flock Lock;
1261 Lock.l_type = F_UNLCK;
1262 Lock.l_whence = SEEK_SET;
1263 Lock.l_start = 0;
1264 Lock.l_len = 0;
1265 if (::fcntl(fd: FD, F_SETLK, &Lock) != -1)
1266 return std::error_code();
1267 return errnoAsErrorCode();
1268}
1269
1270std::error_code closeFile(file_t &F) {
1271 file_t TmpF = F;
1272 F = kInvalidFile;
1273 return Process::SafelyCloseFileDescriptor(FD: TmpF);
1274}
1275
1276template <typename T>
1277static std::error_code remove_directories_impl(const T &Entry,
1278 bool IgnoreErrors) {
1279 std::error_code EC;
1280 directory_iterator Begin(Entry, EC, false);
1281 directory_iterator End;
1282 while (Begin != End) {
1283 auto &Item = *Begin;
1284 ErrorOr<basic_file_status> st = Item.status();
1285 if (st) {
1286 if (is_directory(status: *st)) {
1287 EC = remove_directories_impl(Entry: Item, IgnoreErrors);
1288 if (EC && !IgnoreErrors)
1289 return EC;
1290 }
1291
1292 EC = fs::remove(path: Item.path(), IgnoreNonExisting: true);
1293 if (EC && !IgnoreErrors)
1294 return EC;
1295 } else if (!IgnoreErrors) {
1296 return st.getError();
1297 }
1298
1299 Begin.increment(ec&: EC);
1300 if (EC && !IgnoreErrors)
1301 return EC;
1302 }
1303 return std::error_code();
1304}
1305
1306std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {
1307 auto EC = remove_directories_impl(Entry: path, IgnoreErrors);
1308 if (EC && !IgnoreErrors)
1309 return EC;
1310 EC = fs::remove(path, IgnoreNonExisting: true);
1311 if (EC && !IgnoreErrors)
1312 return EC;
1313 return std::error_code();
1314}
1315
1316std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,
1317 bool expand_tilde) {
1318 dest.clear();
1319 if (path.isTriviallyEmpty())
1320 return std::error_code();
1321
1322 if (expand_tilde) {
1323 SmallString<128> Storage;
1324 path.toVector(Out&: Storage);
1325 expandTildeExpr(Path&: Storage);
1326 return real_path(path: Storage, dest, expand_tilde: false);
1327 }
1328
1329 SmallString<128> Storage;
1330 StringRef P = path.toNullTerminatedStringRef(Out&: Storage);
1331 char Buffer[PATH_MAX];
1332 if (::realpath(name: P.begin(), resolved: Buffer) == nullptr)
1333 return errnoAsErrorCode();
1334 dest.append(in_start: Buffer, in_end: Buffer + strlen(s: Buffer));
1335 return std::error_code();
1336}
1337
1338std::error_code changeFileOwnership(int FD, uint32_t Owner, uint32_t Group) {
1339 auto FChown = [&]() { return ::fchown(fd: FD, owner: Owner, group: Group); };
1340 // Retry if fchown call fails due to interruption.
1341 if ((sys::RetryAfterSignal(Fail: -1, F: FChown)) < 0)
1342 return errnoAsErrorCode();
1343 return std::error_code();
1344}
1345
1346} // end namespace fs
1347
1348namespace path {
1349
1350bool home_directory(SmallVectorImpl<char> &result) {
1351 std::unique_ptr<char[]> Buf;
1352 char *RequestedDir = getenv(name: "HOME");
1353 if (!RequestedDir) {
1354 long BufSize = sysconf(_SC_GETPW_R_SIZE_MAX);
1355 if (BufSize <= 0)
1356 BufSize = 16384;
1357 Buf = std::make_unique<char[]>(num: BufSize);
1358 struct passwd Pwd;
1359 struct passwd *pw = nullptr;
1360 getpwuid_r(uid: getuid(), resultbuf: &Pwd, buffer: Buf.get(), buflen: BufSize, result: &pw);
1361 if (pw && pw->pw_dir)
1362 RequestedDir = pw->pw_dir;
1363 }
1364 if (!RequestedDir)
1365 return false;
1366
1367 result.clear();
1368 result.append(in_start: RequestedDir, in_end: RequestedDir + strlen(s: RequestedDir));
1369 return true;
1370}
1371
1372static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) {
1373#if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR)
1374 // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR.
1375 // macros defined in <unistd.h> on darwin >= 9
1376 int ConfName = TempDir ? _CS_DARWIN_USER_TEMP_DIR : _CS_DARWIN_USER_CACHE_DIR;
1377 size_t ConfLen = confstr(ConfName, nullptr, 0);
1378 if (ConfLen > 0) {
1379 do {
1380 Result.resize(ConfLen);
1381 ConfLen = confstr(ConfName, Result.data(), Result.size());
1382 } while (ConfLen > 0 && ConfLen != Result.size());
1383
1384 if (ConfLen > 0) {
1385 assert(Result.back() == 0);
1386 Result.pop_back();
1387 return true;
1388 }
1389
1390 Result.clear();
1391 }
1392#endif
1393 return false;
1394}
1395
1396bool user_config_directory(SmallVectorImpl<char> &result) {
1397#ifdef __APPLE__
1398 // Mac: ~/Library/Preferences/
1399 if (home_directory(result)) {
1400 append(result, "Library", "Preferences");
1401 return true;
1402 }
1403#else
1404 // XDG_CONFIG_HOME as defined in the XDG Base Directory Specification:
1405 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
1406 if (const char *RequestedDir = getenv(name: "XDG_CONFIG_HOME")) {
1407 result.clear();
1408 result.append(in_start: RequestedDir, in_end: RequestedDir + strlen(s: RequestedDir));
1409 return true;
1410 }
1411#endif
1412 // Fallback: ~/.config
1413 if (!home_directory(result)) {
1414 return false;
1415 }
1416 append(path&: result, a: ".config");
1417 return true;
1418}
1419
1420bool cache_directory(SmallVectorImpl<char> &result) {
1421#ifdef __APPLE__
1422 if (getDarwinConfDir(false /*tempDir*/, result)) {
1423 return true;
1424 }
1425#else
1426 // XDG_CACHE_HOME as defined in the XDG Base Directory Specification:
1427 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
1428 if (const char *RequestedDir = getenv(name: "XDG_CACHE_HOME")) {
1429 result.clear();
1430 result.append(in_start: RequestedDir, in_end: RequestedDir + strlen(s: RequestedDir));
1431 return true;
1432 }
1433#endif
1434 if (!home_directory(result)) {
1435 return false;
1436 }
1437 append(path&: result, a: ".cache");
1438 return true;
1439}
1440
1441static const char *getEnvTempDir() {
1442 // Check whether the temporary directory is specified by an environment
1443 // variable.
1444 const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"};
1445 for (const char *Env : EnvironmentVariables) {
1446 if (const char *Dir = std::getenv(name: Env))
1447 return Dir;
1448 }
1449
1450 return nullptr;
1451}
1452
1453static const char *getDefaultTempDir(bool ErasedOnReboot) {
1454#ifdef P_tmpdir
1455 if ((bool)P_tmpdir)
1456 return P_tmpdir;
1457#endif
1458
1459 if (ErasedOnReboot)
1460 return "/tmp";
1461 return "/var/tmp";
1462}
1463
1464void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
1465 Result.clear();
1466
1467 if (ErasedOnReboot) {
1468 // There is no env variable for the cache directory.
1469 if (const char *RequestedDir = getEnvTempDir()) {
1470 Result.append(in_start: RequestedDir, in_end: RequestedDir + strlen(s: RequestedDir));
1471 return;
1472 }
1473 }
1474
1475 if (getDarwinConfDir(TempDir: ErasedOnReboot, Result))
1476 return;
1477
1478 const char *RequestedDir = getDefaultTempDir(ErasedOnReboot);
1479 Result.append(in_start: RequestedDir, in_end: RequestedDir + strlen(s: RequestedDir));
1480}
1481
1482} // end namespace path
1483
1484namespace fs {
1485
1486#ifdef __APPLE__
1487/// This implementation tries to perform an APFS CoW clone of the file,
1488/// which can be much faster and uses less space.
1489/// Unfortunately fcopyfile(3) does not support COPYFILE_CLONE, so the
1490/// file descriptor variant of this function still uses the default
1491/// implementation.
1492std::error_code copy_file(const Twine &From, const Twine &To) {
1493 std::string FromS = From.str();
1494 std::string ToS = To.str();
1495#if __has_builtin(__builtin_available)
1496 if (__builtin_available(macos 10.12, *)) {
1497 // Optimistically try to use clonefile() and handle errors, rather than
1498 // calling stat() to see if it'll work.
1499 //
1500 // Note: It's okay if From is a symlink. In contrast to the behaviour of
1501 // copyfile() with COPYFILE_CLONE, clonefile() clones targets (not the
1502 // symlink itself) unless the flag CLONE_NOFOLLOW is passed.
1503 if (!clonefile(FromS.c_str(), ToS.c_str(), 0))
1504 return std::error_code();
1505
1506 auto Errno = errno;
1507 switch (Errno) {
1508 case EEXIST: // To already exists.
1509 case ENOTSUP: // Device does not support cloning.
1510 case EXDEV: // From and To are on different devices.
1511 break;
1512 default:
1513 // Anything else will also break copyfile().
1514 return std::error_code(Errno, std::generic_category());
1515 }
1516
1517 // TODO: For EEXIST, profile calling fs::generateUniqueName() and
1518 // clonefile() in a retry loop (then rename() on success) before falling
1519 // back to copyfile(). Depending on the size of the file this could be
1520 // cheaper.
1521 }
1522#endif
1523 if (!copyfile(FromS.c_str(), ToS.c_str(), /*State=*/NULL, COPYFILE_DATA))
1524 return std::error_code();
1525 return errnoAsErrorCode();
1526}
1527#endif // __APPLE__
1528
1529} // end namespace fs
1530
1531} // end namespace sys
1532} // end namespace llvm
1533