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_SYS_MMAN_H 29#include <sys/mman.h> 30#endif 31#if HAVE_DIRENT_H 32# include <dirent.h> 33# define NAMLEN(dirent) strlen((dirent)->d_name) 34#else 35# define dirent direct 36# define NAMLEN(dirent) (dirent)->d_namlen 37# if HAVE_SYS_NDIR_H 38# include <sys/ndir.h> 39# endif 40# if HAVE_SYS_DIR_H 41# include <sys/dir.h> 42# endif 43# if HAVE_NDIR_H 44# include <ndir.h> 45# endif 46#endif 47 48#ifdef __APPLE__ 49#include <mach-o/dyld.h> 50#endif 51 52// Both stdio.h and cstdio are included via different pathes and 53// stdcxx's cstdio doesn't include stdio.h, so it doesn't #undef the macros 54// either. 55#undef ferror 56#undef feof 57 58// For GNU Hurd 59#if defined(__GNU__) && !defined(PATH_MAX) 60# define PATH_MAX 4096 61#endif 62 63using namespace llvm; 64 65namespace llvm { 66namespace sys { 67namespace fs { 68#if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \ 69 defined(__OpenBSD__) || defined(__minix) || defined(__FreeBSD_kernel__) || \ 70 defined(__linux__) || defined(__CYGWIN__) || defined(__DragonFly__) 71static int 72test_dir(char ret[PATH_MAX], const char *dir, const char *bin) 73{ 74 struct stat sb; 75 char fullpath[PATH_MAX]; 76 77 snprintf(fullpath, PATH_MAX, "%s/%s", dir, bin); 78 if (!realpath(fullpath, ret)) 79 return 1; 80 if (stat(fullpath, &sb) != 0) 81 return 1; 82 83 return 0; 84} 85 86static char * 87getprogpath(char ret[PATH_MAX], const char *bin) 88{ 89 char *pv, *s, *t; 90 91 /* First approach: absolute path. */ 92 if (bin[0] == '/') { 93 if (test_dir(ret, "/", bin) == 0) 94 return ret; 95 return nullptr; 96 } 97 98 /* Second approach: relative path. */ 99 if (strchr(bin, '/')) { 100 char cwd[PATH_MAX]; 101 if (!getcwd(cwd, PATH_MAX)) 102 return nullptr; 103 if (test_dir(ret, cwd, bin) == 0) 104 return ret; 105 return nullptr; 106 } 107 108 /* Third approach: $PATH */ 109 if ((pv = getenv("PATH")) == nullptr) 110 return nullptr; 111 s = pv = strdup(pv); 112 if (!pv) 113 return nullptr; 114 while ((t = strsep(&s, ":")) != nullptr) { 115 if (test_dir(ret, t, bin) == 0) { 116 free(pv); 117 return ret; 118 } 119 } 120 free(pv); 121 return nullptr; 122} 123#endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__ 124 125/// GetMainExecutable - Return the path to the main executable, given the 126/// value of argv[0] from program startup. 127std::string getMainExecutable(const char *argv0, void *MainAddr) { 128#if defined(__APPLE__) 129 // On OS X the executable path is saved to the stack by dyld. Reading it 130 // from there is much faster than calling dladdr, especially for large 131 // binaries with symbols. 132 char exe_path[MAXPATHLEN]; 133 uint32_t size = sizeof(exe_path); 134 if (_NSGetExecutablePath(exe_path, &size) == 0) { 135 char link_path[MAXPATHLEN]; 136 if (realpath(exe_path, link_path)) 137 return link_path; 138 } 139#elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \ 140 defined(__OpenBSD__) || defined(__minix) || defined(__DragonFly__) || \ 141 defined(__FreeBSD_kernel__) 142 char exe_path[PATH_MAX]; 143 144 if (getprogpath(exe_path, argv0) != NULL) 145 return exe_path; 146#elif defined(__linux__) || defined(__CYGWIN__) 147 char exe_path[MAXPATHLEN]; 148 StringRef aPath("/proc/self/exe"); 149 if (sys::fs::exists(aPath)) { 150 // /proc is not always mounted under Linux (chroot for example). 151 ssize_t len = readlink(aPath.str().c_str(), exe_path, sizeof(exe_path)); 152 if (len >= 0) 153 return std::string(exe_path, len); 154 } else { 155 // Fall back to the classical detection. 156 if (getprogpath(exe_path, argv0)) 157 return exe_path; 158 } 159#elif defined(HAVE_DLFCN_H) 160 // Use dladdr to get executable path if available. 161 Dl_info DLInfo; 162 int err = dladdr(MainAddr, &DLInfo); 163 if (err == 0) 164 return ""; 165 166 // If the filename is a symlink, we need to resolve and return the location of 167 // the actual executable. 168 char link_path[MAXPATHLEN]; 169 if (realpath(DLInfo.dli_fname, link_path)) 170 return link_path; 171#else 172#error GetMainExecutable is not implemented on this host yet. 173#endif 174 return ""; 175} 176 177TimeValue file_status::getLastModificationTime() const { 178 TimeValue Ret; 179 Ret.fromEpochTime(fs_st_mtime); 180 return Ret; 181} 182 183UniqueID file_status::getUniqueID() const { 184 return UniqueID(fs_st_dev, fs_st_ino); 185} 186 187std::error_code current_path(SmallVectorImpl<char> &result) { 188 result.clear(); 189 190 const char *pwd = ::getenv("PWD"); 191 llvm::sys::fs::file_status PWDStatus, DotStatus; 192 if (pwd && llvm::sys::path::is_absolute(pwd) && 193 !llvm::sys::fs::status(pwd, PWDStatus) && 194 !llvm::sys::fs::status(".", DotStatus) && 195 PWDStatus.getUniqueID() == DotStatus.getUniqueID()) { 196 result.append(pwd, pwd + strlen(pwd)); 197 return std::error_code(); 198 } 199 200#ifdef MAXPATHLEN 201 result.reserve(MAXPATHLEN); 202#else 203// For GNU Hurd 204 result.reserve(1024); 205#endif 206 207 while (true) { 208 if (::getcwd(result.data(), result.capacity()) == nullptr) { 209 // See if there was a real error. 210 if (errno != ENOMEM) 211 return std::error_code(errno, std::generic_category()); 212 // Otherwise there just wasn't enough space. 213 result.reserve(result.capacity() * 2); 214 } else 215 break; 216 } 217 218 result.set_size(strlen(result.data())); 219 return std::error_code(); 220} 221 222std::error_code create_directory(const Twine &path, bool IgnoreExisting, 223 perms Perms) { 224 SmallString<128> path_storage; 225 StringRef p = path.toNullTerminatedStringRef(path_storage); 226 227 if (::mkdir(p.begin(), Perms) == -1) { 228 if (errno != EEXIST || !IgnoreExisting) 229 return std::error_code(errno, std::generic_category()); 230 } 231 232 return std::error_code(); 233} 234 235// Note that we are using symbolic link because hard links are not supported by 236// all filesystems (SMB doesn't). 237std::error_code create_link(const Twine &to, const Twine &from) { 238 // Get arguments. 239 SmallString<128> from_storage; 240 SmallString<128> to_storage; 241 StringRef f = from.toNullTerminatedStringRef(from_storage); 242 StringRef t = to.toNullTerminatedStringRef(to_storage); 243 244 if (::symlink(t.begin(), f.begin()) == -1) 245 return std::error_code(errno, std::generic_category()); 246 247 return std::error_code(); 248} 249 250std::error_code remove(const Twine &path, bool IgnoreNonExisting) { 251 SmallString<128> path_storage; 252 StringRef p = path.toNullTerminatedStringRef(path_storage); 253 254 struct stat buf; 255 if (lstat(p.begin(), &buf) != 0) { 256 if (errno != ENOENT || !IgnoreNonExisting) 257 return std::error_code(errno, std::generic_category()); 258 return std::error_code(); 259 } 260 261 // Note: this check catches strange situations. In all cases, LLVM should 262 // only be involved in the creation and deletion of regular files. This 263 // check ensures that what we're trying to erase is a regular file. It 264 // effectively prevents LLVM from erasing things like /dev/null, any block 265 // special file, or other things that aren't "regular" files. 266 if (!S_ISREG(buf.st_mode) && !S_ISDIR(buf.st_mode) && !S_ISLNK(buf.st_mode)) 267 return make_error_code(errc::operation_not_permitted); 268 269 if (::remove(p.begin()) == -1) { 270 if (errno != ENOENT || !IgnoreNonExisting) 271 return std::error_code(errno, std::generic_category()); 272 } 273 274 return std::error_code(); 275} 276 277std::error_code rename(const Twine &from, const Twine &to) { 278 // Get arguments. 279 SmallString<128> from_storage; 280 SmallString<128> to_storage; 281 StringRef f = from.toNullTerminatedStringRef(from_storage); 282 StringRef t = to.toNullTerminatedStringRef(to_storage); 283 284 if (::rename(f.begin(), t.begin()) == -1) 285 return std::error_code(errno, std::generic_category()); 286 287 return std::error_code(); 288} 289 290std::error_code resize_file(int FD, uint64_t Size) { 291 if (::ftruncate(FD, Size) == -1) 292 return std::error_code(errno, std::generic_category()); 293 294 return std::error_code(); 295} 296 297static int convertAccessMode(AccessMode Mode) { 298 switch (Mode) { 299 case AccessMode::Exist: 300 return F_OK; 301 case AccessMode::Write: 302 return W_OK; 303 case AccessMode::Execute: 304 return R_OK | X_OK; // scripts also need R_OK. 305 } 306 llvm_unreachable("invalid enum"); 307} 308 309std::error_code access(const Twine &Path, AccessMode Mode) { 310 SmallString<128> PathStorage; 311 StringRef P = Path.toNullTerminatedStringRef(PathStorage); 312 313 if (::access(P.begin(), convertAccessMode(Mode)) == -1) 314 return std::error_code(errno, std::generic_category()); 315 316 if (Mode == AccessMode::Execute) { 317 // Don't say that directories are executable. 318 struct stat buf; 319 if (0 != stat(P.begin(), &buf)) 320 return errc::permission_denied; 321 if (!S_ISREG(buf.st_mode)) 322 return errc::permission_denied; 323 } 324 325 return std::error_code(); 326} 327 328bool can_execute(const Twine &Path) { 329 return !access(Path, AccessMode::Execute); 330} 331 332bool equivalent(file_status A, file_status B) { 333 assert(status_known(A) && status_known(B)); 334 return A.fs_st_dev == B.fs_st_dev && 335 A.fs_st_ino == B.fs_st_ino; 336} 337 338std::error_code equivalent(const Twine &A, const Twine &B, bool &result) { 339 file_status fsA, fsB; 340 if (std::error_code ec = status(A, fsA)) 341 return ec; 342 if (std::error_code ec = status(B, fsB)) 343 return ec; 344 result = equivalent(fsA, fsB); 345 return std::error_code(); 346} 347 348static std::error_code fillStatus(int StatRet, const struct stat &Status, 349 file_status &Result) { 350 if (StatRet != 0) { 351 std::error_code ec(errno, std::generic_category()); 352 if (ec == errc::no_such_file_or_directory) 353 Result = file_status(file_type::file_not_found); 354 else 355 Result = file_status(file_type::status_error); 356 return ec; 357 } 358 359 file_type Type = file_type::type_unknown; 360 361 if (S_ISDIR(Status.st_mode)) 362 Type = file_type::directory_file; 363 else if (S_ISREG(Status.st_mode)) 364 Type = file_type::regular_file; 365 else if (S_ISBLK(Status.st_mode)) 366 Type = file_type::block_file; 367 else if (S_ISCHR(Status.st_mode)) 368 Type = file_type::character_file; 369 else if (S_ISFIFO(Status.st_mode)) 370 Type = file_type::fifo_file; 371 else if (S_ISSOCK(Status.st_mode)) 372 Type = file_type::socket_file; 373 374 perms Perms = static_cast<perms>(Status.st_mode); 375 Result = 376 file_status(Type, Perms, Status.st_dev, Status.st_ino, Status.st_mtime, 377 Status.st_uid, Status.st_gid, Status.st_size); 378 379 return std::error_code(); 380} 381 382std::error_code status(const Twine &Path, file_status &Result) { 383 SmallString<128> PathStorage; 384 StringRef P = Path.toNullTerminatedStringRef(PathStorage); 385 386 struct stat Status; 387 int StatRet = ::stat(P.begin(), &Status); 388 return fillStatus(StatRet, Status, Result); 389} 390 391std::error_code status(int FD, file_status &Result) { 392 struct stat Status; 393 int StatRet = ::fstat(FD, &Status); 394 return fillStatus(StatRet, Status, Result); 395} 396 397std::error_code setLastModificationAndAccessTime(int FD, TimeValue Time) { 398#if defined(HAVE_FUTIMENS) 399 timespec Times[2]; 400 Times[0].tv_sec = Time.toEpochTime(); 401 Times[0].tv_nsec = 0; 402 Times[1] = Times[0]; 403 if (::futimens(FD, Times)) 404 return std::error_code(errno, std::generic_category()); 405 return std::error_code(); 406#elif defined(HAVE_FUTIMES) 407 timeval Times[2]; 408 Times[0].tv_sec = Time.toEpochTime(); 409 Times[0].tv_usec = 0; 410 Times[1] = Times[0]; 411 if (::futimes(FD, Times)) 412 return std::error_code(errno, std::generic_category()); 413 return std::error_code(); 414#else 415#warning Missing futimes() and futimens() 416 return make_error_code(errc::function_not_supported); 417#endif 418} 419 420std::error_code mapped_file_region::init(int FD, uint64_t Offset, 421 mapmode Mode) { 422 assert(Size != 0); 423 424 int flags = (Mode == readwrite) ? MAP_SHARED : MAP_PRIVATE; 425 int prot = (Mode == readonly) ? PROT_READ : (PROT_READ | PROT_WRITE); 426 Mapping = ::mmap(nullptr, Size, prot, flags, FD, Offset); 427 if (Mapping == MAP_FAILED) 428 return std::error_code(errno, std::generic_category()); 429 return std::error_code(); 430} 431 432mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length, 433 uint64_t offset, std::error_code &ec) 434 : Size(length), Mapping() { 435 // Make sure that the requested size fits within SIZE_T. 436 if (length > std::numeric_limits<size_t>::max()) { 437 ec = make_error_code(errc::invalid_argument); 438 return; 439 } 440 441 ec = init(fd, offset, mode); 442 if (ec) 443 Mapping = nullptr; 444} 445 446mapped_file_region::~mapped_file_region() { 447 if (Mapping) 448 ::munmap(Mapping, Size); 449} 450 451uint64_t mapped_file_region::size() const { 452 assert(Mapping && "Mapping failed but used anyway!"); 453 return Size; 454} 455 456char *mapped_file_region::data() const { 457 assert(Mapping && "Mapping failed but used anyway!"); 458 return reinterpret_cast<char*>(Mapping); 459} 460 461const char *mapped_file_region::const_data() const { 462 assert(Mapping && "Mapping failed but used anyway!"); 463 return reinterpret_cast<const char*>(Mapping); 464} 465 466int mapped_file_region::alignment() { 467 return Process::getPageSize(); 468} 469 470std::error_code detail::directory_iterator_construct(detail::DirIterState &it, 471 StringRef path){ 472 SmallString<128> path_null(path); 473 DIR *directory = ::opendir(path_null.c_str()); 474 if (!directory) 475 return std::error_code(errno, std::generic_category()); 476 477 it.IterationHandle = reinterpret_cast<intptr_t>(directory); 478 // Add something for replace_filename to replace. 479 path::append(path_null, "."); 480 it.CurrentEntry = directory_entry(path_null.str()); 481 return directory_iterator_increment(it); 482} 483 484std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) { 485 if (it.IterationHandle) 486 ::closedir(reinterpret_cast<DIR *>(it.IterationHandle)); 487 it.IterationHandle = 0; 488 it.CurrentEntry = directory_entry(); 489 return std::error_code(); 490} 491 492std::error_code detail::directory_iterator_increment(detail::DirIterState &it) { 493 errno = 0; 494 dirent *cur_dir = ::readdir(reinterpret_cast<DIR *>(it.IterationHandle)); 495 if (cur_dir == nullptr && errno != 0) { 496 return std::error_code(errno, std::generic_category()); 497 } else if (cur_dir != nullptr) { 498 StringRef name(cur_dir->d_name, NAMLEN(cur_dir)); 499 if ((name.size() == 1 && name[0] == '.') || 500 (name.size() == 2 && name[0] == '.' && name[1] == '.')) 501 return directory_iterator_increment(it); 502 it.CurrentEntry.replace_filename(name); 503 } else 504 return directory_iterator_destruct(it); 505 506 return std::error_code(); 507} 508 509std::error_code openFileForRead(const Twine &Name, int &ResultFD) { 510 SmallString<128> Storage; 511 StringRef P = Name.toNullTerminatedStringRef(Storage); 512 while ((ResultFD = open(P.begin(), O_RDONLY)) < 0) { 513 if (errno != EINTR) 514 return std::error_code(errno, std::generic_category()); 515 } 516 return std::error_code(); 517} 518 519std::error_code openFileForWrite(const Twine &Name, int &ResultFD, 520 sys::fs::OpenFlags Flags, unsigned Mode) { 521 // Verify that we don't have both "append" and "excl". 522 assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) && 523 "Cannot specify both 'excl' and 'append' file creation flags!"); 524 525 int OpenFlags = O_CREAT; 526 527 if (Flags & F_RW) 528 OpenFlags |= O_RDWR; 529 else 530 OpenFlags |= O_WRONLY; 531 532 if (Flags & F_Append) 533 OpenFlags |= O_APPEND; 534 else 535 OpenFlags |= O_TRUNC; 536 537 if (Flags & F_Excl) 538 OpenFlags |= O_EXCL; 539 540 SmallString<128> Storage; 541 StringRef P = Name.toNullTerminatedStringRef(Storage); 542 while ((ResultFD = open(P.begin(), OpenFlags, Mode)) < 0) { 543 if (errno != EINTR) 544 return std::error_code(errno, std::generic_category()); 545 } 546 return std::error_code(); 547} 548 549} // end namespace fs 550 551namespace path { 552 553bool home_directory(SmallVectorImpl<char> &result) { 554 if (char *RequestedDir = getenv("HOME")) { 555 result.clear(); 556 result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); 557 return true; 558 } 559 560 return false; 561} 562 563static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) { 564 #if defined(_CS_DARWIN_USER_TEMP_DIR) && defined(_CS_DARWIN_USER_CACHE_DIR) 565 // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR. 566 // macros defined in <unistd.h> on darwin >= 9 567 int ConfName = TempDir ? _CS_DARWIN_USER_TEMP_DIR 568 : _CS_DARWIN_USER_CACHE_DIR; 569 size_t ConfLen = confstr(ConfName, nullptr, 0); 570 if (ConfLen > 0) { 571 do { 572 Result.resize(ConfLen); 573 ConfLen = confstr(ConfName, Result.data(), Result.size()); 574 } while (ConfLen > 0 && ConfLen != Result.size()); 575 576 if (ConfLen > 0) { 577 assert(Result.back() == 0); 578 Result.pop_back(); 579 return true; 580 } 581 582 Result.clear(); 583 } 584 #endif 585 return false; 586} 587 588static bool getUserCacheDir(SmallVectorImpl<char> &Result) { 589 // First try using XDS_CACHE_HOME env variable, 590 // as specified in XDG Base Directory Specification at 591 // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html 592 if (const char *XdsCacheDir = std::getenv("XDS_CACHE_HOME")) { 593 Result.clear(); 594 Result.append(XdsCacheDir, XdsCacheDir + strlen(XdsCacheDir)); 595 return true; 596 } 597 598 // Try Darwin configuration query 599 if (getDarwinConfDir(false, Result)) 600 return true; 601 602 // Use "$HOME/.cache" if $HOME is available 603 if (home_directory(Result)) { 604 append(Result, ".cache"); 605 return true; 606 } 607 608 return false; 609} 610 611static const char *getEnvTempDir() { 612 // Check whether the temporary directory is specified by an environment 613 // variable. 614 const char *EnvironmentVariables[] = {"TMPDIR", "TMP", "TEMP", "TEMPDIR"}; 615 for (const char *Env : EnvironmentVariables) { 616 if (const char *Dir = std::getenv(Env)) 617 return Dir; 618 } 619 620 return nullptr; 621} 622 623static const char *getDefaultTempDir(bool ErasedOnReboot) { 624#ifdef P_tmpdir 625 if ((bool)P_tmpdir) 626 return P_tmpdir; 627#endif 628 629 if (ErasedOnReboot) 630 return "/tmp"; 631 return "/var/tmp"; 632} 633 634void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) { 635 Result.clear(); 636 637 if (ErasedOnReboot) { 638 // There is no env variable for the cache directory. 639 if (const char *RequestedDir = getEnvTempDir()) { 640 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); 641 return; 642 } 643 } 644 645 if (getDarwinConfDir(ErasedOnReboot, Result)) 646 return; 647 648 const char *RequestedDir = getDefaultTempDir(ErasedOnReboot); 649 Result.append(RequestedDir, RequestedDir + strlen(RequestedDir)); 650} 651 652} // end namespace path 653 654} // end namespace sys 655} // end namespace llvm 656