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::GetRootDirectory() {
90 Path::GetTemporaryDirectory(std::string* ErrMsg ) {
91 #if defined(HAVE_MKDTEMP)
92 // The best way is with mkdtemp but that's not available on many systems,
93 // Linux and FreeBSD have it. Others probably won't.
94 char pathname[MAXPATHLEN];
95 strcpy(pathname,"/tmp/llvm_XXXXXX");
96 if (0 == mkdtemp(pathname)) {
98 std::string(pathname) + ": can't create temporary directory");
102 result.set(pathname);
103 assert(result.isValid() && "mkdtemp didn't create a valid pathname!");
105 #elif defined(HAVE_MKSTEMP)
106 // If no mkdtemp is available, mkstemp can be used to create a temporary file
107 // which is then removed and created as a directory. We prefer this over
108 // mktemp because of mktemp's inherent security and threading risks. We still
109 // have a slight race condition from the time the temporary file is created to
110 // the time it is re-created as a directoy.
111 char pathname[MAXPATHLEN];
112 strcpy(pathname, "/tmp/llvm_XXXXXX");
114 if (-1 == (fd = mkstemp(pathname))) {
116 std::string(pathname) + ": can't create temporary directory");
120 ::unlink(pathname); // start race condition, ignore errors
121 if (-1 == ::mkdir(pathname, S_IRWXU)) { // end race condition
123 std::string(pathname) + ": can't create temporary directory");
127 result.set(pathname);
128 assert(result.isValid() && "mkstemp didn't create a valid pathname!");
130 #elif defined(HAVE_MKTEMP)
131 // If a system doesn't have mkdtemp(3) or mkstemp(3) but it does have
132 // mktemp(3) then we'll assume that system (e.g. AIX) has a reasonable
133 // implementation of mktemp(3) and doesn't follow BSD 4.3's lead of replacing
134 // the XXXXXX with the pid of the process and a letter. That leads to only
135 // twenty six temporary files that can be generated.
136 char pathname[MAXPATHLEN];
137 strcpy(pathname, "/tmp/llvm_XXXXXX");
138 char *TmpName = ::mktemp(pathname);
141 std::string(TmpName) + ": can't create unique directory name");
144 if (-1 == ::mkdir(TmpName, S_IRWXU)) {
146 std::string(TmpName) + ": can't create temporary directory");
151 assert(result.isValid() && "mktemp didn't create a valid pathname!");
154 // This is the worst case implementation. tempnam(3) leaks memory unless its
155 // on an SVID2 (or later) system. On BSD 4.3 it leaks. tmpnam(3) has thread
156 // issues. The mktemp(3) function doesn't have enough variability in the
157 // temporary name generated. So, we provide our own implementation that
158 // increments an integer from a random number seeded by the current time. This
159 // should be sufficiently unique that we don't have many collisions between
160 // processes. Generally LLVM processes don't run very long and don't use very
161 // many temporary files so this shouldn't be a big issue for LLVM.
162 static time_t num = ::time(0);
163 char pathname[MAXPATHLEN];
166 sprintf(pathname, "/tmp/llvm_%010u", unsigned(num));
167 } while ( 0 == access(pathname, F_OK ) );
168 if (-1 == ::mkdir(pathname, S_IRWXU)) {
170 std::string(pathname) + ": can't create temporary directory");
173 result.set(pathname);
174 assert(result.isValid() && "mkstemp didn't create a valid pathname!");
179 static void getPathList(const char*path, std::vector<sys::Path>& Paths) {
180 const char* at = path;
181 const char* delim = strchr(at, ':');
183 while( delim != 0 ) {
184 std::string tmp(at, size_t(delim-at));
185 if (tmpPath.set(tmp))
186 if (tmpPath.canRead())
187 Paths.push_back(tmpPath);
189 delim = strchr(at, ':');
192 if (tmpPath.set(std::string(at)))
193 if (tmpPath.canRead())
194 Paths.push_back(tmpPath);
199 Path::GetSystemLibraryPaths(std::vector<sys::Path>& Paths) {
200 #ifdef LTDL_SHLIBPATH_VAR
201 char* env_var = getenv(LTDL_SHLIBPATH_VAR);
203 getPathList(env_var,Paths);
206 // FIXME: Should this look at LD_LIBRARY_PATH too?
207 Paths.push_back(sys::Path("/usr/local/lib/"));
208 Paths.push_back(sys::Path("/usr/X11R6/lib/"));
209 Paths.push_back(sys::Path("/usr/lib/"));
210 Paths.push_back(sys::Path("/lib/"));
214 Path::GetBytecodeLibraryPaths(std::vector<sys::Path>& Paths) {
215 char * env_var = getenv("LLVM_LIB_SEARCH_PATH");
217 getPathList(env_var,Paths);
222 if (tmpPath.set(LLVM_LIBDIR))
223 if (tmpPath.canRead())
224 Paths.push_back(tmpPath);
227 GetSystemLibraryPaths(Paths);
231 Path::GetLLVMDefaultConfigDir() {
232 return Path("/etc/llvm/");
236 Path::GetUserHomeDirectory() {
237 const char* home = getenv("HOME");
240 if (result.set(home))
243 return GetRootDirectory();
248 Path::getBasename() const {
249 // Find the last slash
250 size_t slash = path.rfind('/');
251 if (slash == std::string::npos)
256 size_t dot = path.rfind('.');
257 if (dot == std::string::npos || dot < slash)
258 return path.substr(slash);
260 return path.substr(slash, dot - slash);
263 bool Path::hasMagicNumber(const std::string &Magic) const {
264 size_t len = Magic.size();
265 assert(len < 1024 && "Request for magic string too long");
266 char* buf = (char*) alloca(1 + len);
267 int fd = ::open(path.c_str(), O_RDONLY);
270 size_t read_len = ::read(fd, buf, len);
278 bool Path::getMagicNumber(std::string& Magic, unsigned len) const {
279 assert(len < 1024 && "Request for magic string too long");
280 char* buf = (char*) alloca(1 + len);
281 int fd = ::open(path.c_str(), O_RDONLY);
284 ssize_t bytes_read = ::read(fd, buf, len);
286 if (ssize_t(len) != bytes_read) {
290 Magic.assign(buf,len);
295 Path::isBytecodeFile() const {
298 int fd = ::open(path.c_str(), O_RDONLY);
301 ssize_t bytes_read = ::read(fd, buffer, 4);
306 return (buffer[0] == 'l' && buffer[1] == 'l' && buffer[2] == 'v' &&
307 (buffer[3] == 'c' || buffer[3] == 'm'));
311 Path::exists() const {
312 return 0 == access(path.c_str(), F_OK );
316 Path::canRead() const {
317 return 0 == access(path.c_str(), F_OK | R_OK );
321 Path::canWrite() const {
322 return 0 == access(path.c_str(), F_OK | W_OK );
326 Path::canExecute() const {
327 if (0 != access(path.c_str(), R_OK | X_OK ))
330 int r = stat(path.c_str(), &st);
331 if (r != 0 || !S_ISREG(st.st_mode))
337 Path::getLast() const {
338 // Find the last slash
339 size_t pos = path.rfind('/');
341 // Handle the corner cases
342 if (pos == std::string::npos)
345 // If the last character is a slash
346 if (pos == path.length()-1) {
347 // Find the second to last slash
348 size_t pos2 = path.rfind('/', pos-1);
349 if (pos2 == std::string::npos)
350 return path.substr(0,pos);
352 return path.substr(pos2+1,pos-pos2-1);
354 // Return everything after the last slash
355 return path.substr(pos+1);
359 Path::getFileStatus(FileStatus &info, std::string *ErrStr) const {
361 if (0 != stat(path.c_str(), &buf))
362 return GetErrno(path + ": can't get status of file '" + path + "'", ErrStr);
363 info.fileSize = buf.st_size;
364 info.modTime.fromEpochTime(buf.st_mtime);
365 info.mode = buf.st_mode;
366 info.user = buf.st_uid;
367 info.group = buf.st_gid;
368 info.isDir = S_ISDIR(buf.st_mode);
369 info.isFile = S_ISREG(buf.st_mode);
373 static bool AddPermissionBits(const Path &File, int bits) {
374 // Get the umask value from the operating system. We want to use it
375 // when changing the file's permissions. Since calling umask() sets
376 // the umask and returns its old value, we must call it a second
377 // time to reset it to the user's preference.
378 int mask = umask(0777); // The arg. to umask is arbitrary.
379 umask(mask); // Restore the umask.
381 // Get the file's current mode.
383 if (File.getFileStatus(Stat)) return false;
385 // Change the file to have whichever permissions bits from 'bits'
386 // that the umask would not disable.
387 if ((chmod(File.c_str(), (Stat.getMode() | (bits & ~mask)))) == -1)
393 bool Path::makeReadableOnDisk(std::string* ErrMsg) {
394 if (!AddPermissionBits(*this, 0444))
395 return MakeErrMsg(ErrMsg, path + ": can't make file readable");
399 bool Path::makeWriteableOnDisk(std::string* ErrMsg) {
400 if (!AddPermissionBits(*this, 0222))
401 return MakeErrMsg(ErrMsg, path + ": can't make file writable");
405 bool Path::makeExecutableOnDisk(std::string* ErrMsg) {
406 if (!AddPermissionBits(*this, 0111))
407 return MakeErrMsg(ErrMsg, path + ": can't make file executable");
412 Path::getDirectoryContents(std::set<Path>& result, std::string* ErrMsg) const {
413 DIR* direntries = ::opendir(path.c_str());
415 return MakeErrMsg(ErrMsg, path + ": can't open directory");
417 std::string dirPath = path;
418 if (!lastIsSlash(dirPath))
422 struct dirent* de = ::readdir(direntries);
423 for ( ; de != 0; de = ::readdir(direntries)) {
424 if (de->d_name[0] != '.') {
425 Path aPath(dirPath + (const char*)de->d_name);
427 if (0 != lstat(aPath.path.c_str(), &st)) {
428 if (S_ISLNK(st.st_mode))
429 continue; // dangling symlink -- ignore
430 return MakeErrMsg(ErrMsg,
431 aPath.path + ": can't determine file object type");
433 result.insert(aPath);
437 closedir(direntries);
442 Path::set(const std::string& a_path) {
445 std::string save(path);
455 Path::appendComponent(const std::string& name) {
458 std::string save(path);
459 if (!lastIsSlash(path))
470 Path::eraseComponent() {
471 size_t slashpos = path.rfind('/',path.size());
472 if (slashpos == 0 || slashpos == std::string::npos) {
476 if (slashpos == path.size() - 1)
477 slashpos = path.rfind('/',slashpos-1);
478 if (slashpos == std::string::npos) {
482 path.erase(slashpos);
487 Path::appendSuffix(const std::string& suffix) {
488 std::string save(path);
499 Path::eraseSuffix() {
500 std::string save = path;
501 size_t dotpos = path.rfind('.',path.size());
502 size_t slashpos = path.rfind('/',path.size());
503 if (dotpos != std::string::npos) {
504 if (slashpos == std::string::npos || dotpos > slashpos+1) {
505 path.erase(dotpos, path.size()-dotpos);
515 Path::createDirectoryOnDisk( bool create_parents, std::string* ErrMsg ) {
516 // Get a writeable copy of the path name
517 char pathname[MAXPATHLEN];
518 path.copy(pathname,MAXPATHLEN);
520 // Null-terminate the last component
521 int lastchar = path.length() - 1 ;
522 if (pathname[lastchar] == '/')
523 pathname[lastchar] = 0;
525 pathname[lastchar+1] = 0;
527 // If we're supposed to create intermediate directories
528 if ( create_parents ) {
529 // Find the end of the initial name component
530 char * next = strchr(pathname,'/');
531 if ( pathname[0] == '/')
532 next = strchr(&pathname[1],'/');
534 // Loop through the directory components until we're done
535 while ( next != 0 ) {
537 if (0 != access(pathname, F_OK | R_OK | W_OK))
538 if (0 != mkdir(pathname, S_IRWXU | S_IRWXG)) {
539 return MakeErrMsg(ErrMsg,
540 std::string(pathname) + ": can't create directory");
543 next = strchr(next+1,'/');
548 if (0 != access(pathname, F_OK | R_OK))
549 if (0 != mkdir(pathname, S_IRWXU | S_IRWXG)) {
550 return MakeErrMsg(ErrMsg,
551 std::string(pathname) + ": can't create directory");
557 Path::createFileOnDisk(std::string* ErrMsg) {
559 int fd = ::creat(path.c_str(), S_IRUSR | S_IWUSR);
561 return MakeErrMsg(ErrMsg, path + ": can't create file");
567 Path::createTemporaryFileOnDisk(bool reuse_current, std::string* ErrMsg) {
568 // Make this into a unique file name
569 makeUnique( reuse_current );
572 int fd = ::open(path.c_str(), O_WRONLY|O_CREAT|O_TRUNC, 0666);
574 return MakeErrMsg(ErrMsg, path + ": can't create temporary file");
580 Path::eraseFromDisk(bool remove_contents, std::string *ErrStr) const {
582 if (getFileStatus(Status, ErrStr))
585 // Note: this check catches strange situations. In all cases, LLVM should only
586 // be involved in the creation and deletion of regular files. This check
587 // ensures that what we're trying to erase is a regular file. It effectively
588 // prevents LLVM from erasing things like /dev/null, any block special file,
589 // or other things that aren't "regular" files.
591 if (unlink(path.c_str()) != 0)
592 return GetErrno(path + ": can't destroy file", ErrStr);
597 if (ErrStr) *ErrStr = "not a file or directory";
600 if (remove_contents) {
601 // Recursively descend the directory to remove its contents.
602 std::string cmd = "/bin/rm -rf " + path;
607 // Otherwise, try to just remove the one directory.
608 char pathname[MAXPATHLEN];
609 path.copy(pathname, MAXPATHLEN);
610 int lastchar = path.length() - 1 ;
611 if (pathname[lastchar] == '/')
612 pathname[lastchar] = 0;
614 pathname[lastchar+1] = 0;
616 if (rmdir(pathname) != 0)
617 return GetErrno(std::string(pathname) + ": can't destroy directory",
623 Path::renamePathOnDisk(const Path& newName, std::string* ErrMsg) {
624 if (0 != ::rename(path.c_str(), newName.c_str()))
625 return MakeErrMsg(ErrMsg, std::string("can't rename '") + path + "' as '" +
626 newName.toString() + "' ");
631 Path::setStatusInfoOnDisk(const FileStatus &si, std::string *ErrStr) const {
633 utb.actime = si.modTime.toPosixTime();
634 utb.modtime = utb.actime;
635 if (0 != ::utime(path.c_str(),&utb))
636 return GetErrno(path + ": can't set file modification time", ErrStr);
637 if (0 != ::chmod(path.c_str(),si.mode))
638 return GetErrno(path + ": can't set mode", ErrStr);
643 sys::CopyFile(const sys::Path &Dest, const sys::Path &Src) {
647 inFile = ::open(Src.c_str(), O_RDONLY);
649 ThrowErrno(Src.toString() + ": can't open source file to copy: ");
651 outFile = ::open(Dest.c_str(), O_WRONLY|O_CREAT, 0666);
653 ThrowErrno(Dest.toString() +": can't create destination file for copy: ");
655 char Buffer[16*1024];
656 while (ssize_t Amt = ::read(inFile, Buffer, 16*1024)) {
658 if (errno != EINTR && errno != EAGAIN)
659 ThrowErrno(Src.toString()+": can't read source file: ");
661 char *BufPtr = Buffer;
663 ssize_t AmtWritten = ::write(outFile, BufPtr, Amt);
664 if (AmtWritten == -1) {
665 if (errno != EINTR && errno != EAGAIN)
666 ThrowErrno(Dest.toString() + ": can't write destination file: ");
669 BufPtr += AmtWritten;
686 Path::makeUnique(bool reuse_current) {
687 if (reuse_current && !exists())
688 return; // File doesn't exist already, just use it!
690 // Append an XXXXXX pattern to the end of the file for use with mkstemp,
691 // mktemp or our own implementation.
692 char *FNBuffer = (char*) alloca(path.size()+8);
693 path.copy(FNBuffer,path.size());
694 strcpy(FNBuffer+path.size(), "-XXXXXX");
696 #if defined(HAVE_MKSTEMP)
698 if ((TempFD = mkstemp(FNBuffer)) == -1) {
699 ThrowErrno(path + ": can't make unique filename");
702 // We don't need to hold the temp file descriptor... we will trust that no one
703 // will overwrite/delete the file before we can open it again.
708 #elif defined(HAVE_MKTEMP)
709 // If we don't have mkstemp, use the old and obsolete mktemp function.
710 if (mktemp(FNBuffer) == 0) {
711 ThrowErrno(path + ": can't make unique filename");
717 // Okay, looks like we have to do it all by our lonesome.
718 static unsigned FCounter = 0;
719 unsigned offset = path.size() + 1;
720 while ( FCounter < 999999 && exists()) {
721 sprintf(FNBuffer+offset,"%06u",++FCounter);
724 if (FCounter > 999999)
725 throw std::string(path + ": can't make unique filename: too many files");