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 86using namespace llvm; 87 88namespace llvm { 89namespace sys { 90namespace 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) 95static int 96test_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 110static char * 111getprogpath(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. 151std::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) && defined(HAVE_DLADDR) 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 201TimePoint<> file_status::getLastAccessedTime() const { 202 return toTimePoint(fs_st_atime); 203} 204 205TimePoint<> file_status::getLastModificationTime() const { 206 return toTimePoint(fs_st_mtime); 207} 208 209UniqueID file_status::getUniqueID() const { 210 return UniqueID(fs_st_dev, fs_st_ino); 211} 212 213ErrorOr<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 225std::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 260std::error_code set_current_path(const Twine &path) { 261 SmallString<128> path_storage; 262 StringRef p = path.toNullTerminatedStringRef(path_storage); 263 264 if (::chdir(p.begin()) == -1) 265 return std::error_code(errno, std::generic_category()); 266 267 return std::error_code(); 268} 269 270std::error_code create_directory(const Twine &path, bool IgnoreExisting, 271 perms Perms) { 272 SmallString<128> path_storage; 273 StringRef p = path.toNullTerminatedStringRef(path_storage); 274 275 if (::mkdir(p.begin(), Perms) == -1) { 276 if (errno != EEXIST || !IgnoreExisting) 277 return std::error_code(errno, std::generic_category()); 278 } 279 280 return std::error_code(); 281} 282 283// Note that we are using symbolic link because hard links are not supported by 284// all filesystems (SMB doesn't). 285std::error_code create_link(const Twine &to, const Twine &from) { 286 // Get arguments. 287 SmallString<128> from_storage; 288 SmallString<128> to_storage; 289 StringRef f = from.toNullTerminatedStringRef(from_storage); 290 StringRef t = to.toNullTerminatedStringRef(to_storage); 291 292 if (::symlink(t.begin(), f.begin()) == -1) 293 return std::error_code(errno, std::generic_category()); 294 295 return std::error_code(); 296} 297 298std::error_code create_hard_link(const Twine &to, const Twine &from) { 299 // Get arguments. 300 SmallString<128> from_storage; 301 SmallString<128> to_storage; 302 StringRef f = from.toNullTerminatedStringRef(from_storage); 303 StringRef t = to.toNullTerminatedStringRef(to_storage); 304 305 if (::link(t.begin(), f.begin()) == -1) 306 return std::error_code(errno, std::generic_category()); 307 308 return std::error_code(); 309} 310 311std::error_code remove(const Twine &path, bool IgnoreNonExisting) { 312 SmallString<128> path_storage; 313 StringRef p = path.toNullTerminatedStringRef(path_storage); 314 315 struct stat buf; 316 if (lstat(p.begin(), &buf) != 0) { 317 if (errno != ENOENT || !IgnoreNonExisting) 318 return std::error_code(errno, std::generic_category()); 319 return std::error_code(); 320 } 321 322 // Note: this check catches strange situations. In all cases, LLVM should 323 // only be involved in the creation and deletion of regular files. This 324 // check ensures that what we're trying to erase is a regular file. It 325 // effectively prevents LLVM from erasing things like /dev/null, any block 326 // special file, or other things that aren't "regular" files. 327 if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode)) 328 return make_error_code(errc::operation_not_permitted); 329 330 if (::remove(p.begin()) == -1) { 331 if (errno != ENOENT || !IgnoreNonExisting) 332 return std::error_code(errno, std::generic_category()); 333 } 334 335 return std::error_code(); 336} 337 338std::error_code rename(const Twine &from, const Twine &to) { 339 // Get arguments. 340 SmallString<128> from_storage; 341 SmallString<128> to_storage; 342 StringRef f = from.toNullTerminatedStringRef(from_storage); 343 StringRef t = to.toNullTerminatedStringRef(to_storage); 344 345 if (::rename(f.begin(), t.begin()) == -1) 346 return std::error_code(errno, std::generic_category()); 347 348 return std::error_code(); 349} 350 351std::error_code resize_file(int FD, uint64_t Size) { 352#if defined(HAVE_POSIX_FALLOCATE) 353 // If we have posix_fallocate use it. Unlike ftruncate it always allocates 354 // space, so we get an error if the disk is full. 355 if (int Err = ::posix_fallocate(FD, 0, Size)) 356 return std::error_code(Err, std::generic_category()); 357#else 358 // Use ftruncate as a fallback. It may or may not allocate space. At least on 359 // OS X with HFS+ it does. 360 if (::ftruncate(FD, Size) == -1) 361 return std::error_code(errno, std::generic_category()); 362#endif 363 364 return std::error_code(); 365} 366 367static int convertAccessMode(AccessMode Mode) { 368 switch (Mode) { 369 case AccessMode::Exist: 370 return F_OK; 371 case AccessMode::Write: 372 return W_OK; 373 case AccessMode::Execute: 374 return R_OK | X_OK; // scripts also need R_OK. 375 } 376 llvm_unreachable("invalid enum"); 377} 378 379std::error_code access(const Twine &Path, AccessMode Mode) { 380 SmallString<128> PathStorage; 381 StringRef P = Path.toNullTerminatedStringRef(PathStorage); 382 383 if (::access(P.begin(), convertAccessMode(Mode)) == -1) 384 return std::error_code(errno, std::generic_category()); 385 386 if (Mode == AccessMode::Execute) { 387 // Don't say that directories are executable. 388 struct stat buf; 389 if (0 != stat(P.begin(), &buf)) 390 return errc::permission_denied; 391 if (!S_ISREG(buf.st_mode)) 392 return errc::permission_denied; 393 } 394 395 return std::error_code(); 396} 397 398bool can_execute(const Twine &Path) { 399 return !access(Path, AccessMode::Execute); 400} 401 402bool equivalent(file_status A, file_status B) { 403 assert(status_known(A) && status_known(B)); 404 return A.fs_st_dev == B.fs_st_dev && 405 A.fs_st_ino == B.fs_st_ino; 406} 407 408std::error_code equivalent(const Twine &A, const Twine &B, bool &result) { 409 file_status fsA, fsB; 410 if (std::error_code ec = status(A, fsA)) 411 return ec; 412 if (std::error_code ec = status(B, fsB)) 413 return ec; 414 result = equivalent(fsA, fsB); 415 return std::error_code(); 416} 417 418static std::error_code fillStatus(int StatRet, const struct stat &Status, 419 file_status &Result) { 420 if (StatRet != 0) { 421 std::error_code ec(errno, std::generic_category()); 422 if (ec == errc::no_such_file_or_directory) 423 Result = file_status(file_type::file_not_found); 424 else 425 Result = file_status(file_type::status_error); 426 return ec; 427 } 428 429 file_type Type = file_type::type_unknown; 430 431 if (S_ISDIR(Status.st_mode)) 432 Type = file_type::directory_file; 433 else if (S_ISREG(Status.st_mode)) 434 Type = file_type::regular_file; 435 else if (S_ISBLK(Status.st_mode)) 436 Type = file_type::block_file; 437 else if (S_ISCHR(Status.st_mode)) 438 Type = file_type::character_file; 439 else if (S_ISFIFO(Status.st_mode)) 440 Type = file_type::fifo_file; 441 else if (S_ISSOCK(Status.st_mode)) 442 Type = file_type::socket_file; 443 444 perms Perms = static_cast<perms>(Status.st_mode); 445 Result = 446 file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_atime, 447 Status.st_mtime, Status.st_uid, Status.st_gid, 448 Status.st_size); 449 450 return std::error_code(); 451} 452 453std::error_code status(const Twine &Path, file_status &Result) { 454 SmallString<128> PathStorage; 455 StringRef P = Path.toNullTerminatedStringRef(PathStorage); 456 457 struct stat Status; 458 int StatRet = ::stat(P.begin(), &Status); 459 return fillStatus(StatRet, Status, Result); 460} 461 462std::error_code status(int FD, file_status &Result) { 463 struct stat Status; 464 int StatRet = ::fstat(FD, &Status); 465 return fillStatus(StatRet, Status, Result); 466} 467 468std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) { 469#if defined(HAVE_FUTIMENS) 470 timespec Times[2]; 471 Times[0] = Times[1] = sys::toTimeSpec(Time); 472 if (::futimens(FD, Times)) 473 return std::error_code(errno, std::generic_category()); 474 return std::error_code(); 475#elif defined(HAVE_FUTIMES) 476 timeval Times[2]; 477 Times[0] = Times[1] = sys::toTimeVal( 478 std::chrono::time_point_cast<std::chrono::microseconds>(Time)); 479 if (::futimes(FD, Times)) 480 return std::error_code(errno, std::generic_category()); 481 return std::error_code(); 482#else 483#warning Missing futimes() and futimens() 484 return make_error_code(errc::function_not_supported); 485#endif 486} 487 488std::error_code mapped_file_region::init(int FD, uint64_t Offset, 489 mapmode Mode) { 490 assert(Size != 0); 491 492 int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE; 493 int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE); 494 Mapping = ::mmap(nullptr, Size, prot, flags, FD, Offset); 495 if (Mapping == MAP_FAILED) 496 return std::error_code(errno, std::generic_category()); 497 return std::error_code(); 498} 499 500mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length, 501 uint64_t offset, std::error_code &ec) 502 : Size(length), Mapping() { 503 // Make sure that the requested size fits within SIZE_T. 504 if (length > std::numeric_limits<size_t>::max()) { 505 ec = make_error_code(errc::invalid_argument); 506 return; 507 } 508 509 ec = init(fd, offset, mode); 510 if (ec) 511 Mapping = nullptr; 512} 513 514mapped_file_region::~mapped_file_region() { 515 if (Mapping) 516 ::munmap(Mapping, Size); 517} 518 519uint64_t mapped_file_region::size() const { 520 assert(Mapping && "Mapping failed but used anyway!"); 521 return Size; 522} 523 524char *mapped_file_region::data() const { 525 assert(Mapping && "Mapping failed but used anyway!"); 526 return reinterpret_cast<char*>(Mapping); 527} 528 529const char *mapped_file_region::const_data() const { 530 assert(Mapping && "Mapping failed but used anyway!"); 531 return reinterpret_cast<const char*>(Mapping); 532} 533 534int mapped_file_region::alignment() { 535 return Process::getPageSize(); 536} 537 538std::error_code detail::directory_iterator_construct(detail::DirIterState &it, 539 StringRef path){ 540 SmallString<128> path_null(path); 541 DIR *directory = ::opendir(path_null.c_str()); 542 if (!directory) 543 return std::error_code(errno, std::generic_category()); 544 545 it.IterationHandle = reinterpret_cast<intptr_t>(directory); 546 // Add something for replace_filename to replace. 547 path::append(path_null, "."); 548 it.CurrentEntry = directory_entry(path_null.str()); 549 return directory_iterator_increment(it); 550} 551 552std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) { 553 if (it.IterationHandle) 554 ::closedir(reinterpret_cast<DIR *>(it.IterationHandle)); 555 it.IterationHandle = 0; 556 it.CurrentEntry = directory_entry(); 557 return std::error_code(); 558} 559 560std::error_code detail::directory_iterator_increment(detail::DirIterState &it) { 561 errno = 0; 562 dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle)); 563 if (cur_dir == nullptr && errno != 0) { 564 return std::error_code(errno, std::generic_category()); 565 } else if (cur_dir != nullptr) { 566 StringRef name(cur_dir->d_name, NAMLEN(cur_dir)); 567 if ((name.size() == 1 && name[0] == '.') || 568 (name.size() == 2 && name[0] == '.' && name[1] == '.')) 569 return directory_iterator_increment(it); 570 it.CurrentEntry.replace_filename(name); 571 } else 572 return directory_iterator_destruct(it); 573 574 return std::error_code(); 575} 576 577#if !defined(F_GETPATH) 578static bool hasProcSelfFD() { 579 // If we have a /proc filesystem mounted, we can quickly establish the 580 // real name of the file with readlink 581 static const bool Result = (::access("/proc/self/fd", R_OK) == 0); 582 return Result; 583} 584#endif 585 586std::error_code openFileForRead(const Twine &Name, int &ResultFD, 587 SmallVectorImpl<char> *RealPath) { 588 SmallString<128> Storage; 589 StringRef P = Name.toNullTerminatedStringRef(Storage); 590 int OpenFlags = O_RDONLY; 591#ifdef O_CLOEXEC 592 OpenFlags |= O_CLOEXEC; 593#endif 594 while ((ResultFD = open(P.begin(), OpenFlags)) < 0) { 595 if (errno != EINTR) 596 return std::error_code(errno, std::generic_category()); 597 } 598#ifndef O_CLOEXEC 599 int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC); 600 (void)r; 601 assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed"); 602#endif 603 // Attempt to get the real name of the file, if the user asked 604 if(!RealPath) 605 return std::error_code(); 606 RealPath->clear(); 607#if defined(F_GETPATH) 608 // When F_GETPATH is availble, it is the quickest way to get 609 // the real path name. 610 char Buffer[MAXPATHLEN]; 611 if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1) 612 RealPath->append(Buffer, Buffer + strlen(Buffer)); 613#else 614 char Buffer[PATH_MAX]; 615 if (hasProcSelfFD()) { 616 char ProcPath[64]; 617 snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD); 618 ssize_t CharCount = ::readlink(ProcPath, Buffer, sizeof(Buffer)); 619 if (CharCount > 0) 620 RealPath->append(Buffer, Buffer + CharCount); 621 } else { 622 // Use ::realpath to get the real path name 623 if (::realpath(P.begin(), Buffer) != nullptr) 624 RealPath->append(Buffer, Buffer + strlen(Buffer)); 625 } 626#endif 627 return std::error_code(); 628} 629 630std::error_code openFileForWrite(const Twine &Name, int &ResultFD, 631 sys::fs::OpenFlags Flags, unsigned Mode) { 632 // Verify that we don't have both "append" and "excl". 633 assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) && 634 "Cannot specify both 'excl' and 'append' file creation flags!"); 635 636 int OpenFlags = O_CREAT; 637 638#ifdef O_CLOEXEC 639 OpenFlags |= O_CLOEXEC; 640#endif 641 642 if (Flags & F_RW) 643 OpenFlags |= O_RDWR; 644 else 645 OpenFlags |= O_WRONLY; 646 647 if (Flags & F_Append) 648 OpenFlags |= O_APPEND; 649 else 650 OpenFlags |= O_TRUNC; 651 652 if (Flags & F_Excl) 653 OpenFlags |= O_EXCL; 654 655 SmallString<128> Storage; 656 StringRef P = Name.toNullTerminatedStringRef(Storage); 657 while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) { 658 if (errno != EINTR) 659 return std::error_code(errno, std::generic_category()); 660 } 661#ifndef O_CLOEXEC 662 int r = fcntl(ResultFD, F_SETFD, FD_CLOEXEC); 663 (void)r; 664 assert(r == 0 && "fcntl(F_SETFD, FD_CLOEXEC) failed"); 665#endif 666 return std::error_code(); 667} 668 669std::error_code getPathFromOpenFD(int FD, SmallVectorImpl<char> &ResultPath) { 670 if (FD < 0) 671 return make_error_code(errc::bad_file_descriptor); 672 673#if defined(F_GETPATH) 674 // When F_GETPATH is availble, it is the quickest way to get 675 // the path from a file descriptor. 676 ResultPath.reserve(MAXPATHLEN); 677 if (::fcntl(FD, F_GETPATH, ResultPath.begin()) == -1) 678 return std::error_code(errno, std::generic_category()); 679 680 ResultPath.set_size(strlen(ResultPath.begin())); 681#else 682 // If we have a /proc filesystem mounted, we can quickly establish the 683 // real name of the file with readlink. Otherwise, we don't know how to 684 // get the filename from a file descriptor. Give up. 685 if (!fs::hasProcSelfFD()) 686 return make_error_code(errc::function_not_supported); 687 688 ResultPath.reserve(PATH_MAX); 689 char ProcPath[64]; 690 snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", FD); 691 ssize_t CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity()); 692 if (CharCount < 0) 693 return std::error_code(errno, std::generic_category()); 694 695 // Was the filename truncated? 696 if (static_cast<size_t>(CharCount) == ResultPath.capacity()) { 697 // Use lstat to get the size of the filename 698 struct stat sb; 699 if (::lstat(ProcPath, &sb) < 0) 700 return std::error_code(errno, std::generic_category()); 701 702 ResultPath.reserve(sb.st_size + 1); 703 CharCount = ::readlink(ProcPath, ResultPath.begin(), ResultPath.capacity()); 704 if (CharCount < 0) 705 return std::error_code(errno, std::generic_category()); 706 707 // Test for race condition: did the link size change? 708 if (CharCount > sb.st_size) 709 return std::error_code(ENAMETOOLONG, std::generic_category()); 710 } 711 ResultPath.set_size(static_cast<size_t>(CharCount)); 712#endif 713 return std::error_code(); 714} 715 716} // end namespace fs 717 718namespace path { 719 720bool home_directory(SmallVectorImpl<char> &result) { 721 if (char *RequestedDir = getenv("HOME")) { 722 result.clear(); 723 result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); 724 return true; 725 } 726 727 return false; 728} 729 730static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) { 731 #if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR) 732 // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR. 733 // macros defined in <unistd.h> on darwin >= 9 734 int ConfName = TempDir ? _CS_DARWIN_USER_TEMP_DIR 735 : _CS_DARWIN_USER_CACHE_DIR; 736 size_t ConfLen = confstr(ConfName, nullptr, 0); 737 if (ConfLen > 0) { 738 do { 739 Result.resize(ConfLen); 740 ConfLen = confstr(ConfName, Result.data(), Result.size()); 741 } while (ConfLen > 0 && ConfLen != Result.size()); 742 743 if (ConfLen > 0) { 744 assert(Result.back() == 0); 745 Result.pop_back(); 746 return true; 747 } 748 749 Result.clear(); 750 } 751 #endif 752 return false; 753} 754 755static bool getUserCacheDir(SmallVectorImpl<char> &Result) { 756 // First try using XDG_CACHE_HOME env variable, 757 // as specified in XDG Base Directory Specification at 758 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html 759 if (const char *XdgCacheDir = std::getenv("XDG_CACHE_HOME")) { 760 Result.clear(); 761 Result.append(XdgCacheDir, XdgCacheDir + strlen(XdgCacheDir)); 762 return true; 763 } 764 765 // Try Darwin configuration query 766 if (getDarwinConfDir(false, Result)) 767 return true; 768 769 // Use "$HOME/.cache" if $HOME is available 770 if (home_directory(Result)) { 771 append(Result, ".cache"); 772 return true; 773 } 774 775 return false; 776} 777 778static const char *getEnvTempDir() { 779 // Check whether the temporary directory is specified by an environment 780 // variable. 781 const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"}; 782 for (const char *Env : EnvironmentVariables) { 783 if (const char *Dir = std::getenv(Env)) 784 return Dir; 785 } 786 787 return nullptr; 788} 789 790static const char *getDefaultTempDir(bool ErasedOnReboot) { 791#ifdef P_tmpdir 792 if ((bool)P_tmpdir) 793 return P_tmpdir; 794#endif 795 796 if (ErasedOnReboot) 797 return "/tmp"; 798 return "/var/tmp"; 799} 800 801void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) { 802 Result.clear(); 803 804 if (ErasedOnReboot) { 805 // There is no env variable for the cache directory. 806 if (const char *RequestedDir = getEnvTempDir()) { 807 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); 808 return; 809 } 810 } 811 812 if (getDarwinConfDir(ErasedOnReboot, Result)) 813 return; 814 815 const char *RequestedDir = getDefaultTempDir(ErasedOnReboot); 816 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); 817} 818 819} // end namespace path 820 821} // end namespace sys 822} // end namespace llvm 823