1 //===- llvm/System/Unix/Path.cpp - Unix Path Implementation -----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Reid Spencer and is distributed under the
6 // University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Unix specific portion of the Path class.
12 //===----------------------------------------------------------------------===//
14 //===----------------------------------------------------------------------===//
15 //=== WARNING: Implementation here must contain only generic UNIX code that
16 //=== is guaranteed to work on *all* UNIX variants.
17 //===----------------------------------------------------------------------===//
19 #include "llvm/Config/alloca.h"
35 # define NAMLEN(dirent) strlen((dirent)->d_name)
37 # define dirent direct
38 # define NAMLEN(dirent) (dirent)->d_namlen
40 # include <sys/ndir.h>
50 // Put in a hack for Cygwin which falsely reports that the mkdtemp function
51 // is available when it is not.
57 inline bool lastIsSlash(const std::string& path) {
58 return !path.empty() && path[path.length() - 1] == '/';
67 Path::isValid() const {
68 // Check some obvious things
71 else if (path.length() >= MAXPATHLEN)
74 // Check that the characters are ascii chars
75 size_t len = path.length();
77 while (i < len && isascii(path[i]))
83 Path::isAbsolute() const {
86 return path[0] == '/';
89 Path::GetRootDirectory() {
96 Path::GetTemporaryDirectory(std::string* ErrMsg ) {
97 #if defined(HAVE_MKDTEMP)
98 // The best way is with mkdtemp but that's not available on many systems,
99 // Linux and FreeBSD have it. Others probably won't.
100 char pathname[MAXPATHLEN];
101 strcpy(pathname,"/tmp/llvm_XXXXXX");
102 if (0 == mkdtemp(pathname)) {
104 std::string(pathname) + ": can't create temporary directory");
108 result.set(pathname);
109 assert(result.isValid() && "mkdtemp didn't create a valid pathname!");
111 #elif defined(HAVE_MKSTEMP)
112 // If no mkdtemp is available, mkstemp can be used to create a temporary file
113 // which is then removed and created as a directory. We prefer this over
114 // mktemp because of mktemp's inherent security and threading risks. We still
115 // have a slight race condition from the time the temporary file is created to
116 // the time it is re-created as a directoy.
117 char pathname[MAXPATHLEN];
118 strcpy(pathname, "/tmp/llvm_XXXXXX");
120 if (-1 == (fd = mkstemp(pathname))) {
122 std::string(pathname) + ": can't create temporary directory");
126 ::unlink(pathname); // start race condition, ignore errors
127 if (-1 == ::mkdir(pathname, S_IRWXU)) { // end race condition
129 std::string(pathname) + ": can't create temporary directory");
133 result.set(pathname);
134 assert(result.isValid() && "mkstemp didn't create a valid pathname!");
136 #elif defined(HAVE_MKTEMP)
137 // If a system doesn't have mkdtemp(3) or mkstemp(3) but it does have
138 // mktemp(3) then we'll assume that system (e.g. AIX) has a reasonable
139 // implementation of mktemp(3) and doesn't follow BSD 4.3's lead of replacing
140 // the XXXXXX with the pid of the process and a letter. That leads to only
141 // twenty six temporary files that can be generated.
142 char pathname[MAXPATHLEN];
143 strcpy(pathname, "/tmp/llvm_XXXXXX");
144 char *TmpName = ::mktemp(pathname);
147 std::string(TmpName) + ": can't create unique directory name");
150 if (-1 == ::mkdir(TmpName, S_IRWXU)) {
152 std::string(TmpName) + ": can't create temporary directory");
157 assert(result.isValid() && "mktemp didn't create a valid pathname!");
160 // This is the worst case implementation. tempnam(3) leaks memory unless its
161 // on an SVID2 (or later) system. On BSD 4.3 it leaks. tmpnam(3) has thread
162 // issues. The mktemp(3) function doesn't have enough variability in the
163 // temporary name generated. So, we provide our own implementation that
164 // increments an integer from a random number seeded by the current time. This
165 // should be sufficiently unique that we don't have many collisions between
166 // processes. Generally LLVM processes don't run very long and don't use very
167 // many temporary files so this shouldn't be a big issue for LLVM.
168 static time_t num = ::time(0);
169 char pathname[MAXPATHLEN];
172 sprintf(pathname, "/tmp/llvm_%010u", unsigned(num));
173 } while ( 0 == access(pathname, F_OK ) );
174 if (-1 == ::mkdir(pathname, S_IRWXU)) {
176 std::string(pathname) + ": can't create temporary directory");
180 result.set(pathname);
181 assert(result.isValid() && "mkstemp didn't create a valid pathname!");
186 static void getPathList(const char*path, std::vector<sys::Path>& Paths) {
187 const char* at = path;
188 const char* delim = strchr(at, ':');
190 while( delim != 0 ) {
191 std::string tmp(at, size_t(delim-at));
192 if (tmpPath.set(tmp))
193 if (tmpPath.canRead())
194 Paths.push_back(tmpPath);
196 delim = strchr(at, ':');
199 if (tmpPath.set(std::string(at)))
200 if (tmpPath.canRead())
201 Paths.push_back(tmpPath);
206 Path::GetSystemLibraryPaths(std::vector<sys::Path>& Paths) {
207 #ifdef LTDL_SHLIBPATH_VAR
208 char* env_var = getenv(LTDL_SHLIBPATH_VAR);
210 getPathList(env_var,Paths);
213 // FIXME: Should this look at LD_LIBRARY_PATH too?
214 Paths.push_back(sys::Path("/usr/local/lib/"));
215 Paths.push_back(sys::Path("/usr/X11R6/lib/"));
216 Paths.push_back(sys::Path("/usr/lib/"));
217 Paths.push_back(sys::Path("/lib/"));
221 Path::GetBytecodeLibraryPaths(std::vector<sys::Path>& Paths) {
222 char * env_var = getenv("LLVM_LIB_SEARCH_PATH");
224 getPathList(env_var,Paths);
229 if (tmpPath.set(LLVM_LIBDIR))
230 if (tmpPath.canRead())
231 Paths.push_back(tmpPath);
234 GetSystemLibraryPaths(Paths);
238 Path::GetLLVMDefaultConfigDir() {
239 return Path("/etc/llvm/");
243 Path::GetUserHomeDirectory() {
244 const char* home = getenv("HOME");
247 if (result.set(home))
250 return GetRootDirectory();
255 Path::getBasename() const {
256 // Find the last slash
257 size_t slash = path.rfind('/');
258 if (slash == std::string::npos)
263 size_t dot = path.rfind('.');
264 if (dot == std::string::npos || dot < slash)
265 return path.substr(slash);
267 return path.substr(slash, dot - slash);
270 bool Path::hasMagicNumber(const std::string &Magic) const {
271 size_t len = Magic.size();
272 assert(len < 1024 && "Request for magic string too long");
273 char* buf = (char*) alloca(1 + len);
274 int fd = ::open(path.c_str(), O_RDONLY);
277 size_t read_len = ::read(fd, buf, len);
285 bool Path::getMagicNumber(std::string& Magic, unsigned len) const {
286 assert(len < 1024 && "Request for magic string too long");
287 char* buf = (char*) alloca(1 + len);
288 int fd = ::open(path.c_str(), O_RDONLY);
291 ssize_t bytes_read = ::read(fd, buf, len);
293 if (ssize_t(len) != bytes_read) {
297 Magic.assign(buf,len);
302 Path::isBytecodeFile() const {
305 int fd = ::open(path.c_str(), O_RDONLY);
308 ssize_t bytes_read = ::read(fd, buffer, 4);
313 return (buffer[0] == 'l' && buffer[1] == 'l' && buffer[2] == 'v' &&
314 (buffer[3] == 'c' || buffer[3] == 'm'));
318 Path::exists() const {
319 return 0 == access(path.c_str(), F_OK );
323 Path::canRead() const {
324 return 0 == access(path.c_str(), F_OK | R_OK );
328 Path::canWrite() const {
329 return 0 == access(path.c_str(), F_OK | W_OK );
333 Path::canExecute() const {
334 if (0 != access(path.c_str(), R_OK | X_OK ))
337 int r = stat(path.c_str(), &st);
338 if (r != 0 || !S_ISREG(st.st_mode))
344 Path::getLast() const {
345 // Find the last slash
346 size_t pos = path.rfind('/');
348 // Handle the corner cases
349 if (pos == std::string::npos)
352 // If the last character is a slash
353 if (pos == path.length()-1) {
354 // Find the second to last slash
355 size_t pos2 = path.rfind('/', pos-1);
356 if (pos2 == std::string::npos)
357 return path.substr(0,pos);
359 return path.substr(pos2+1,pos-pos2-1);
361 // Return everything after the last slash
362 return path.substr(pos+1);
366 Path::getFileStatus(FileStatus &info, bool update, std::string *ErrStr) const {
367 if (status == 0 || update) {
369 if (0 != stat(path.c_str(), &buf))
370 return MakeErrMsg(ErrStr, path + ": can't get status of file");
372 status = new FileStatus;
373 status->fileSize = buf.st_size;
374 status->modTime.fromEpochTime(buf.st_mtime);
375 status->mode = buf.st_mode;
376 status->user = buf.st_uid;
377 status->group = buf.st_gid;
378 status->uniqueID = uint64_t(buf.st_ino);
379 status->isDir = S_ISDIR(buf.st_mode);
380 status->isFile = S_ISREG(buf.st_mode);
386 static bool AddPermissionBits(const Path &File, int bits) {
387 // Get the umask value from the operating system. We want to use it
388 // when changing the file's permissions. Since calling umask() sets
389 // the umask and returns its old value, we must call it a second
390 // time to reset it to the user's preference.
391 int mask = umask(0777); // The arg. to umask is arbitrary.
392 umask(mask); // Restore the umask.
394 // Get the file's current mode.
396 if (File.getFileStatus(Stat)) return false;
398 // Change the file to have whichever permissions bits from 'bits'
399 // that the umask would not disable.
400 if ((chmod(File.c_str(), (Stat.getMode() | (bits & ~mask)))) == -1)
406 bool Path::makeReadableOnDisk(std::string* ErrMsg) {
407 if (!AddPermissionBits(*this, 0444))
408 return MakeErrMsg(ErrMsg, path + ": can't make file readable");
412 bool Path::makeWriteableOnDisk(std::string* ErrMsg) {
413 if (!AddPermissionBits(*this, 0222))
414 return MakeErrMsg(ErrMsg, path + ": can't make file writable");
418 bool Path::makeExecutableOnDisk(std::string* ErrMsg) {
419 if (!AddPermissionBits(*this, 0111))
420 return MakeErrMsg(ErrMsg, path + ": can't make file executable");
425 Path::getDirectoryContents(std::set<Path>& result, std::string* ErrMsg) const {
426 DIR* direntries = ::opendir(path.c_str());
428 return MakeErrMsg(ErrMsg, path + ": can't open directory");
430 std::string dirPath = path;
431 if (!lastIsSlash(dirPath))
435 struct dirent* de = ::readdir(direntries);
436 for ( ; de != 0; de = ::readdir(direntries)) {
437 if (de->d_name[0] != '.') {
438 Path aPath(dirPath + (const char*)de->d_name);
440 if (0 != lstat(aPath.path.c_str(), &st)) {
441 if (S_ISLNK(st.st_mode))
442 continue; // dangling symlink -- ignore
443 return MakeErrMsg(ErrMsg,
444 aPath.path + ": can't determine file object type");
446 result.insert(aPath);
450 closedir(direntries);
455 Path::set(const std::string& a_path) {
458 std::string save(path);
468 Path::appendComponent(const std::string& name) {
471 std::string save(path);
472 if (!lastIsSlash(path))
483 Path::eraseComponent() {
484 size_t slashpos = path.rfind('/',path.size());
485 if (slashpos == 0 || slashpos == std::string::npos) {
489 if (slashpos == path.size() - 1)
490 slashpos = path.rfind('/',slashpos-1);
491 if (slashpos == std::string::npos) {
495 path.erase(slashpos);
500 Path::appendSuffix(const std::string& suffix) {
501 std::string save(path);
512 Path::eraseSuffix() {
513 std::string save = path;
514 size_t dotpos = path.rfind('.',path.size());
515 size_t slashpos = path.rfind('/',path.size());
516 if (dotpos != std::string::npos) {
517 if (slashpos == std::string::npos || dotpos > slashpos+1) {
518 path.erase(dotpos, path.size()-dotpos);
528 Path::createDirectoryOnDisk( bool create_parents, std::string* ErrMsg ) {
529 // Get a writeable copy of the path name
530 char pathname[MAXPATHLEN];
531 path.copy(pathname,MAXPATHLEN);
533 // Null-terminate the last component
534 int lastchar = path.length() - 1 ;
535 if (pathname[lastchar] == '/')
536 pathname[lastchar] = 0;
538 pathname[lastchar+1] = 0;
540 // If we're supposed to create intermediate directories
541 if ( create_parents ) {
542 // Find the end of the initial name component
543 char * next = strchr(pathname,'/');
544 if ( pathname[0] == '/')
545 next = strchr(&pathname[1],'/');
547 // Loop through the directory components until we're done
548 while ( next != 0 ) {
550 if (0 != access(pathname, F_OK | R_OK | W_OK))
551 if (0 != mkdir(pathname, S_IRWXU | S_IRWXG)) {
552 return MakeErrMsg(ErrMsg,
553 std::string(pathname) + ": can't create directory");
556 next = strchr(next+1,'/');
561 if (0 != access(pathname, F_OK | R_OK))
562 if (0 != mkdir(pathname, S_IRWXU | S_IRWXG)) {
563 return MakeErrMsg(ErrMsg,
564 std::string(pathname) + ": can't create directory");
570 Path::createFileOnDisk(std::string* ErrMsg) {
572 int fd = ::creat(path.c_str(), S_IRUSR | S_IWUSR);
574 return MakeErrMsg(ErrMsg, path + ": can't create file");
580 Path::createTemporaryFileOnDisk(bool reuse_current, std::string* ErrMsg) {
581 // Make this into a unique file name
582 if (makeUnique( reuse_current, ErrMsg ))
586 int fd = ::open(path.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0666);
588 return MakeErrMsg(ErrMsg, path + ": can't create temporary file");
594 Path::eraseFromDisk(bool remove_contents, std::string *ErrStr) const {
596 if (getFileStatus(Status, ErrStr))
599 // Note: this check catches strange situations. In all cases, LLVM should only
600 // be involved in the creation and deletion of regular files. This check
601 // ensures that what we're trying to erase is a regular file. It effectively
602 // prevents LLVM from erasing things like /dev/null, any block special file,
603 // or other things that aren't "regular" files.
605 if (unlink(path.c_str()) != 0)
606 return MakeErrMsg(ErrStr, path + ": can't destroy file");
611 if (ErrStr) *ErrStr = "not a file or directory";
614 if (remove_contents) {
615 // Recursively descend the directory to remove its contents.
616 std::string cmd = "/bin/rm -rf " + path;
621 // Otherwise, try to just remove the one directory.
622 char pathname[MAXPATHLEN];
623 path.copy(pathname, MAXPATHLEN);
624 int lastchar = path.length() - 1 ;
625 if (pathname[lastchar] == '/')
626 pathname[lastchar] = 0;
628 pathname[lastchar+1] = 0;
630 if (rmdir(pathname) != 0)
631 return MakeErrMsg(ErrStr,
632 std::string(pathname) + ": can't destroy directory");
637 Path::renamePathOnDisk(const Path& newName, std::string* ErrMsg) {
638 if (0 != ::rename(path.c_str(), newName.c_str()))
639 return MakeErrMsg(ErrMsg, std::string("can't rename '") + path + "' as '" +
640 newName.toString() + "' ");
645 Path::setStatusInfoOnDisk(const FileStatus &si, std::string *ErrStr) const {
647 utb.actime = si.modTime.toPosixTime();
648 utb.modtime = utb.actime;
649 if (0 != ::utime(path.c_str(),&utb))
650 return MakeErrMsg(ErrStr, path + ": can't set file modification time");
651 if (0 != ::chmod(path.c_str(),si.mode))
652 return MakeErrMsg(ErrStr, path + ": can't set mode");
657 sys::CopyFile(const sys::Path &Dest, const sys::Path &Src, std::string* ErrMsg){
660 inFile = ::open(Src.c_str(), O_RDONLY);
662 return MakeErrMsg(ErrMsg, Src.toString() +
663 ": can't open source file to copy");
665 outFile = ::open(Dest.c_str(), O_WRONLY|O_CREAT, 0666);
668 return MakeErrMsg(ErrMsg, Dest.toString() +
669 ": can't create destination file for copy");
672 char Buffer[16*1024];
673 while (ssize_t Amt = ::read(inFile, Buffer, 16*1024)) {
675 if (errno != EINTR && errno != EAGAIN) {
678 return MakeErrMsg(ErrMsg, Src.toString()+": can't read source file: ");
681 char *BufPtr = Buffer;
683 ssize_t AmtWritten = ::write(outFile, BufPtr, Amt);
684 if (AmtWritten == -1) {
685 if (errno != EINTR && errno != EAGAIN) {
688 return MakeErrMsg(ErrMsg, Dest.toString() +
689 ": can't write destination file: ");
693 BufPtr += AmtWritten;
704 Path::makeUnique(bool reuse_current, std::string* ErrMsg) {
705 if (reuse_current && !exists())
706 return false; // File doesn't exist already, just use it!
708 // Append an XXXXXX pattern to the end of the file for use with mkstemp,
709 // mktemp or our own implementation.
710 char *FNBuffer = (char*) alloca(path.size()+8);
711 path.copy(FNBuffer,path.size());
712 strcpy(FNBuffer+path.size(), "-XXXXXX");
714 #if defined(HAVE_MKSTEMP)
716 if ((TempFD = mkstemp(FNBuffer)) == -1)
717 return MakeErrMsg(ErrMsg, path + ": can't make unique filename");
719 // We don't need to hold the temp file descriptor... we will trust that no one
720 // will overwrite/delete the file before we can open it again.
725 #elif defined(HAVE_MKTEMP)
726 // If we don't have mkstemp, use the old and obsolete mktemp function.
727 if (mktemp(FNBuffer) == 0)
728 return MakeErrMsg(ErrMsg, path + ": can't make unique filename");
733 // Okay, looks like we have to do it all by our lonesome.
734 static unsigned FCounter = 0;
735 unsigned offset = path.size() + 1;
736 while ( FCounter < 999999 && exists()) {
737 sprintf(FNBuffer+offset,"%06u",++FCounter);
740 if (FCounter > 999999)
741 return MakeErrMsg(ErrMsg,
742 path + ": can't make unique filename: too many files");
747 } // end llvm namespace