From 222e2a7620e6520ffaf4fc4e69d79c18da31542e Mon Sep 17 00:00:00 2001 From: "Zancanaro; Carlo" Date: Mon, 24 Sep 2012 09:58:17 +1000 Subject: Add the clang library to the repo (with some of my changes, too). --- clang/lib/Basic/FileManager.cpp | 600 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 600 insertions(+) create mode 100644 clang/lib/Basic/FileManager.cpp (limited to 'clang/lib/Basic/FileManager.cpp') diff --git a/clang/lib/Basic/FileManager.cpp b/clang/lib/Basic/FileManager.cpp new file mode 100644 index 0000000..fd6d334 --- /dev/null +++ b/clang/lib/Basic/FileManager.cpp @@ -0,0 +1,600 @@ +//===--- FileManager.cpp - File System Probing and Caching ----------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the FileManager interface. +// +//===----------------------------------------------------------------------===// +// +// TODO: This should index all interesting directories with dirent calls. +// getdirentries ? +// opendir/readdir_r/closedir ? +// +//===----------------------------------------------------------------------===// + +#include "clang/Basic/FileManager.h" +#include "clang/Basic/FileSystemStatCache.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/Support/FileSystem.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/system_error.h" +#include "llvm/Config/llvm-config.h" +#include +#include +#include + +// FIXME: This is terrible, we need this for ::close. +#if !defined(_MSC_VER) && !defined(__MINGW32__) +#include +#include +#else +#include +#endif +using namespace clang; + +// FIXME: Enhance libsystem to support inode and other fields. +#include + +/// NON_EXISTENT_DIR - A special value distinct from null that is used to +/// represent a dir name that doesn't exist on the disk. +#define NON_EXISTENT_DIR reinterpret_cast((intptr_t)-1) + +/// NON_EXISTENT_FILE - A special value distinct from null that is used to +/// represent a filename that doesn't exist on the disk. +#define NON_EXISTENT_FILE reinterpret_cast((intptr_t)-1) + + +FileEntry::~FileEntry() { + // If this FileEntry owns an open file descriptor that never got used, close + // it. + if (FD != -1) ::close(FD); +} + +//===----------------------------------------------------------------------===// +// Windows. +//===----------------------------------------------------------------------===// + +#ifdef LLVM_ON_WIN32 + +namespace { + static std::string GetFullPath(const char *relPath) { + char *absPathStrPtr = _fullpath(NULL, relPath, 0); + assert(absPathStrPtr && "_fullpath() returned NULL!"); + + std::string absPath(absPathStrPtr); + + free(absPathStrPtr); + return absPath; + } +} + +class FileManager::UniqueDirContainer { + /// UniqueDirs - Cache from full path to existing directories/files. + /// + llvm::StringMap UniqueDirs; + +public: + /// getDirectory - Return an existing DirectoryEntry with the given + /// name if there is already one; otherwise create and return a + /// default-constructed DirectoryEntry. + DirectoryEntry &getDirectory(const char *Name, + const struct stat & /*StatBuf*/) { + std::string FullPath(GetFullPath(Name)); + return UniqueDirs.GetOrCreateValue(FullPath).getValue(); + } + + size_t size() const { return UniqueDirs.size(); } +}; + +class FileManager::UniqueFileContainer { + /// UniqueFiles - Cache from full path to existing directories/files. + /// + llvm::StringMap UniqueFiles; + +public: + /// getFile - Return an existing FileEntry with the given name if + /// there is already one; otherwise create and return a + /// default-constructed FileEntry. + FileEntry &getFile(const char *Name, const struct stat & /*StatBuf*/) { + std::string FullPath(GetFullPath(Name)); + + // Lowercase string because Windows filesystem is case insensitive. + FullPath = StringRef(FullPath).lower(); + return UniqueFiles.GetOrCreateValue(FullPath).getValue(); + } + + size_t size() const { return UniqueFiles.size(); } +}; + +//===----------------------------------------------------------------------===// +// Unix-like Systems. +//===----------------------------------------------------------------------===// + +#else + +class FileManager::UniqueDirContainer { + /// UniqueDirs - Cache from ID's to existing directories/files. + std::map, DirectoryEntry> UniqueDirs; + +public: + /// getDirectory - Return an existing DirectoryEntry with the given + /// ID's if there is already one; otherwise create and return a + /// default-constructed DirectoryEntry. + DirectoryEntry &getDirectory(const char * /*Name*/, + const struct stat &StatBuf) { + return UniqueDirs[std::make_pair(StatBuf.st_dev, StatBuf.st_ino)]; + } + + size_t size() const { return UniqueDirs.size(); } +}; + +class FileManager::UniqueFileContainer { + /// UniqueFiles - Cache from ID's to existing directories/files. + std::set UniqueFiles; + +public: + /// getFile - Return an existing FileEntry with the given ID's if + /// there is already one; otherwise create and return a + /// default-constructed FileEntry. + FileEntry &getFile(const char * /*Name*/, const struct stat &StatBuf) { + return + const_cast( + *UniqueFiles.insert(FileEntry(StatBuf.st_dev, + StatBuf.st_ino, + StatBuf.st_mode)).first); + } + + size_t size() const { return UniqueFiles.size(); } +}; + +#endif + +//===----------------------------------------------------------------------===// +// Common logic. +//===----------------------------------------------------------------------===// + +FileManager::FileManager(const FileSystemOptions &FSO) + : FileSystemOpts(FSO), + UniqueRealDirs(*new UniqueDirContainer()), + UniqueRealFiles(*new UniqueFileContainer()), + SeenDirEntries(64), SeenFileEntries(64), NextFileUID(0) { + NumDirLookups = NumFileLookups = 0; + NumDirCacheMisses = NumFileCacheMisses = 0; +} + +FileManager::~FileManager() { + delete &UniqueRealDirs; + delete &UniqueRealFiles; + for (unsigned i = 0, e = VirtualFileEntries.size(); i != e; ++i) + delete VirtualFileEntries[i]; + for (unsigned i = 0, e = VirtualDirectoryEntries.size(); i != e; ++i) + delete VirtualDirectoryEntries[i]; +} + +void FileManager::addStatCache(FileSystemStatCache *statCache, + bool AtBeginning) { + assert(statCache && "No stat cache provided?"); + if (AtBeginning || StatCache.get() == 0) { + statCache->setNextStatCache(StatCache.take()); + StatCache.reset(statCache); + return; + } + + FileSystemStatCache *LastCache = StatCache.get(); + while (LastCache->getNextStatCache()) + LastCache = LastCache->getNextStatCache(); + + LastCache->setNextStatCache(statCache); +} + +void FileManager::removeStatCache(FileSystemStatCache *statCache) { + if (!statCache) + return; + + if (StatCache.get() == statCache) { + // This is the first stat cache. + StatCache.reset(StatCache->takeNextStatCache()); + return; + } + + // Find the stat cache in the list. + FileSystemStatCache *PrevCache = StatCache.get(); + while (PrevCache && PrevCache->getNextStatCache() != statCache) + PrevCache = PrevCache->getNextStatCache(); + + assert(PrevCache && "Stat cache not found for removal"); + PrevCache->setNextStatCache(statCache->getNextStatCache()); +} + +/// \brief Retrieve the directory that the given file name resides in. +/// Filename can point to either a real file or a virtual file. +static const DirectoryEntry *getDirectoryFromFile(FileManager &FileMgr, + StringRef Filename, + bool CacheFailure) { + if (Filename.empty()) + return NULL; + + if (llvm::sys::path::is_separator(Filename[Filename.size() - 1])) + return NULL; // If Filename is a directory. + + StringRef DirName = llvm::sys::path::parent_path(Filename); + // Use the current directory if file has no path component. + if (DirName.empty()) + DirName = "."; + + return FileMgr.getDirectory(DirName, CacheFailure); +} + +/// Add all ancestors of the given path (pointing to either a file or +/// a directory) as virtual directories. +void FileManager::addAncestorsAsVirtualDirs(StringRef Path) { + StringRef DirName = llvm::sys::path::parent_path(Path); + if (DirName.empty()) + return; + + llvm::StringMapEntry &NamedDirEnt = + SeenDirEntries.GetOrCreateValue(DirName); + + // When caching a virtual directory, we always cache its ancestors + // at the same time. Therefore, if DirName is already in the cache, + // we don't need to recurse as its ancestors must also already be in + // the cache. + if (NamedDirEnt.getValue()) + return; + + // Add the virtual directory to the cache. + DirectoryEntry *UDE = new DirectoryEntry; + UDE->Name = NamedDirEnt.getKeyData(); + NamedDirEnt.setValue(UDE); + VirtualDirectoryEntries.push_back(UDE); + + // Recursively add the other ancestors. + addAncestorsAsVirtualDirs(DirName); +} + +/// getDirectory - Lookup, cache, and verify the specified directory +/// (real or virtual). This returns NULL if the directory doesn't +/// exist. +/// +const DirectoryEntry *FileManager::getDirectory(StringRef DirName, + bool CacheFailure) { + // stat doesn't like trailing separators. + // At least, on Win32 MSVCRT, stat() cannot strip trailing '/'. + // (though it can strip '\\') + if (DirName.size() > 1 && llvm::sys::path::is_separator(DirName.back())) + DirName = DirName.substr(0, DirName.size()-1); + + ++NumDirLookups; + llvm::StringMapEntry &NamedDirEnt = + SeenDirEntries.GetOrCreateValue(DirName); + + // See if there was already an entry in the map. Note that the map + // contains both virtual and real directories. + if (NamedDirEnt.getValue()) + return NamedDirEnt.getValue() == NON_EXISTENT_DIR + ? 0 : NamedDirEnt.getValue(); + + ++NumDirCacheMisses; + + // By default, initialize it to invalid. + NamedDirEnt.setValue(NON_EXISTENT_DIR); + + // Get the null-terminated directory name as stored as the key of the + // SeenDirEntries map. + const char *InterndDirName = NamedDirEnt.getKeyData(); + + // Check to see if the directory exists. + struct stat StatBuf; + if (getStatValue(InterndDirName, StatBuf, 0/*directory lookup*/)) { + // There's no real directory at the given path. + if (!CacheFailure) + SeenDirEntries.erase(DirName); + return 0; + } + + // It exists. See if we have already opened a directory with the + // same inode (this occurs on Unix-like systems when one dir is + // symlinked to another, for example) or the same path (on + // Windows). + DirectoryEntry &UDE = UniqueRealDirs.getDirectory(InterndDirName, StatBuf); + + NamedDirEnt.setValue(&UDE); + if (!UDE.getName()) { + // We don't have this directory yet, add it. We use the string + // key from the SeenDirEntries map as the string. + UDE.Name = InterndDirName; + } + + return &UDE; +} + +/// getFile - Lookup, cache, and verify the specified file (real or +/// virtual). This returns NULL if the file doesn't exist. +/// +const FileEntry *FileManager::getFile(StringRef Filename, bool openFile, + bool CacheFailure) { + ++NumFileLookups; + + // See if there is already an entry in the map. + llvm::StringMapEntry &NamedFileEnt = + SeenFileEntries.GetOrCreateValue(Filename); + + // See if there is already an entry in the map. + if (NamedFileEnt.getValue()) + return NamedFileEnt.getValue() == NON_EXISTENT_FILE + ? 0 : NamedFileEnt.getValue(); + + ++NumFileCacheMisses; + + // By default, initialize it to invalid. + NamedFileEnt.setValue(NON_EXISTENT_FILE); + + // Get the null-terminated file name as stored as the key of the + // SeenFileEntries map. + const char *InterndFileName = NamedFileEnt.getKeyData(); + + // Look up the directory for the file. When looking up something like + // sys/foo.h we'll discover all of the search directories that have a 'sys' + // subdirectory. This will let us avoid having to waste time on known-to-fail + // searches when we go to find sys/bar.h, because all the search directories + // without a 'sys' subdir will get a cached failure result. + const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename, + CacheFailure); + if (DirInfo == 0) { // Directory doesn't exist, file can't exist. + if (!CacheFailure) + SeenFileEntries.erase(Filename); + + return 0; + } + + // FIXME: Use the directory info to prune this, before doing the stat syscall. + // FIXME: This will reduce the # syscalls. + + // Nope, there isn't. Check to see if the file exists. + int FileDescriptor = -1; + struct stat StatBuf; + if (getStatValue(InterndFileName, StatBuf, &FileDescriptor)) { + // There's no real file at the given path. + if (!CacheFailure) + SeenFileEntries.erase(Filename); + + return 0; + } + + if (FileDescriptor != -1 && !openFile) { + close(FileDescriptor); + FileDescriptor = -1; + } + + // It exists. See if we have already opened a file with the same inode. + // This occurs when one dir is symlinked to another, for example. + FileEntry &UFE = UniqueRealFiles.getFile(InterndFileName, StatBuf); + + NamedFileEnt.setValue(&UFE); + if (UFE.getName()) { // Already have an entry with this inode, return it. + // If the stat process opened the file, close it to avoid a FD leak. + if (FileDescriptor != -1) + close(FileDescriptor); + + return &UFE; + } + + // Otherwise, we don't have this directory yet, add it. + // FIXME: Change the name to be a char* that points back to the + // 'SeenFileEntries' key. + UFE.Name = InterndFileName; + UFE.Size = StatBuf.st_size; + UFE.ModTime = StatBuf.st_mtime; + UFE.Dir = DirInfo; + UFE.UID = NextFileUID++; + UFE.FD = FileDescriptor; + return &UFE; +} + +const FileEntry * +FileManager::getVirtualFile(StringRef Filename, off_t Size, + time_t ModificationTime) { + ++NumFileLookups; + + // See if there is already an entry in the map. + llvm::StringMapEntry &NamedFileEnt = + SeenFileEntries.GetOrCreateValue(Filename); + + // See if there is already an entry in the map. + if (NamedFileEnt.getValue() && NamedFileEnt.getValue() != NON_EXISTENT_FILE) + return NamedFileEnt.getValue(); + + ++NumFileCacheMisses; + + // By default, initialize it to invalid. + NamedFileEnt.setValue(NON_EXISTENT_FILE); + + addAncestorsAsVirtualDirs(Filename); + FileEntry *UFE = 0; + + // Now that all ancestors of Filename are in the cache, the + // following call is guaranteed to find the DirectoryEntry from the + // cache. + const DirectoryEntry *DirInfo = getDirectoryFromFile(*this, Filename, + /*CacheFailure=*/true); + assert(DirInfo && + "The directory of a virtual file should already be in the cache."); + + // Check to see if the file exists. If so, drop the virtual file + int FileDescriptor = -1; + struct stat StatBuf; + const char *InterndFileName = NamedFileEnt.getKeyData(); + if (getStatValue(InterndFileName, StatBuf, &FileDescriptor) == 0) { + // If the stat process opened the file, close it to avoid a FD leak. + if (FileDescriptor != -1) + close(FileDescriptor); + + StatBuf.st_size = Size; + StatBuf.st_mtime = ModificationTime; + UFE = &UniqueRealFiles.getFile(InterndFileName, StatBuf); + + NamedFileEnt.setValue(UFE); + + // If we had already opened this file, close it now so we don't + // leak the descriptor. We're not going to use the file + // descriptor anyway, since this is a virtual file. + if (UFE->FD != -1) { + close(UFE->FD); + UFE->FD = -1; + } + + // If we already have an entry with this inode, return it. + if (UFE->getName()) + return UFE; + } + + if (!UFE) { + UFE = new FileEntry(); + VirtualFileEntries.push_back(UFE); + NamedFileEnt.setValue(UFE); + } + + UFE->Name = InterndFileName; + UFE->Size = Size; + UFE->ModTime = ModificationTime; + UFE->Dir = DirInfo; + UFE->UID = NextFileUID++; + UFE->FD = -1; + return UFE; +} + +void FileManager::FixupRelativePath(SmallVectorImpl &path) const { + StringRef pathRef(path.data(), path.size()); + + if (FileSystemOpts.WorkingDir.empty() + || llvm::sys::path::is_absolute(pathRef)) + return; + + SmallString<128> NewPath(FileSystemOpts.WorkingDir); + llvm::sys::path::append(NewPath, pathRef); + path = NewPath; +} + +llvm::MemoryBuffer *FileManager:: +getBufferForFile(const FileEntry *Entry, std::string *ErrorStr) { + OwningPtr Result; + llvm::error_code ec; + + const char *Filename = Entry->getName(); + // If the file is already open, use the open file descriptor. + if (Entry->FD != -1) { + ec = llvm::MemoryBuffer::getOpenFile(Entry->FD, Filename, Result, + Entry->getSize()); + if (ErrorStr) + *ErrorStr = ec.message(); + + close(Entry->FD); + Entry->FD = -1; + return Result.take(); + } + + // Otherwise, open the file. + + if (FileSystemOpts.WorkingDir.empty()) { + ec = llvm::MemoryBuffer::getFile(Filename, Result, Entry->getSize()); + if (ec && ErrorStr) + *ErrorStr = ec.message(); + return Result.take(); + } + + SmallString<128> FilePath(Entry->getName()); + FixupRelativePath(FilePath); + ec = llvm::MemoryBuffer::getFile(FilePath.str(), Result, Entry->getSize()); + if (ec && ErrorStr) + *ErrorStr = ec.message(); + return Result.take(); +} + +llvm::MemoryBuffer *FileManager:: +getBufferForFile(StringRef Filename, std::string *ErrorStr) { + OwningPtr Result; + llvm::error_code ec; + if (FileSystemOpts.WorkingDir.empty()) { + ec = llvm::MemoryBuffer::getFile(Filename, Result); + if (ec && ErrorStr) + *ErrorStr = ec.message(); + return Result.take(); + } + + SmallString<128> FilePath(Filename); + FixupRelativePath(FilePath); + ec = llvm::MemoryBuffer::getFile(FilePath.c_str(), Result); + if (ec && ErrorStr) + *ErrorStr = ec.message(); + return Result.take(); +} + +/// getStatValue - Get the 'stat' information for the specified path, +/// using the cache to accelerate it if possible. This returns true +/// if the path points to a virtual file or does not exist, or returns +/// false if it's an existent real file. If FileDescriptor is NULL, +/// do directory look-up instead of file look-up. +bool FileManager::getStatValue(const char *Path, struct stat &StatBuf, + int *FileDescriptor) { + // FIXME: FileSystemOpts shouldn't be passed in here, all paths should be + // absolute! + if (FileSystemOpts.WorkingDir.empty()) + return FileSystemStatCache::get(Path, StatBuf, FileDescriptor, + StatCache.get()); + + SmallString<128> FilePath(Path); + FixupRelativePath(FilePath); + + return FileSystemStatCache::get(FilePath.c_str(), StatBuf, FileDescriptor, + StatCache.get()); +} + +bool FileManager::getNoncachedStatValue(StringRef Path, + struct stat &StatBuf) { + SmallString<128> FilePath(Path); + FixupRelativePath(FilePath); + + return ::stat(FilePath.c_str(), &StatBuf) != 0; +} + +void FileManager::GetUniqueIDMapping( + SmallVectorImpl &UIDToFiles) const { + UIDToFiles.clear(); + UIDToFiles.resize(NextFileUID); + + // Map file entries + for (llvm::StringMap::const_iterator + FE = SeenFileEntries.begin(), FEEnd = SeenFileEntries.end(); + FE != FEEnd; ++FE) + if (FE->getValue() && FE->getValue() != NON_EXISTENT_FILE) + UIDToFiles[FE->getValue()->getUID()] = FE->getValue(); + + // Map virtual file entries + for (SmallVector::const_iterator + VFE = VirtualFileEntries.begin(), VFEEnd = VirtualFileEntries.end(); + VFE != VFEEnd; ++VFE) + if (*VFE && *VFE != NON_EXISTENT_FILE) + UIDToFiles[(*VFE)->getUID()] = *VFE; +} + + +void FileManager::PrintStats() const { + llvm::errs() << "\n*** File Manager Stats:\n"; + llvm::errs() << UniqueRealFiles.size() << " real files found, " + << UniqueRealDirs.size() << " real dirs found.\n"; + llvm::errs() << VirtualFileEntries.size() << " virtual files found, " + << VirtualDirectoryEntries.size() << " virtual dirs found.\n"; + llvm::errs() << NumDirLookups << " dir lookups, " + << NumDirCacheMisses << " dir cache misses.\n"; + llvm::errs() << NumFileLookups << " file lookups, " + << NumFileCacheMisses << " file cache misses.\n"; + + //llvm::errs() << PagesMapped << BytesOfPagesMapped << FSLookups; +} -- cgit v1.2.3