| //===--- FileManager.h - File System Probing and Caching --------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines the FileManager interface. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CLANG_FILEMANAGER_H |
| #define LLVM_CLANG_FILEMANAGER_H |
| |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/StringMap.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/ADT/OwningPtr.h" |
| #include "llvm/Support/Allocator.h" |
| #include "llvm/Config/config.h" // for mode_t |
| // FIXME: Enhance libsystem to support inode and other fields in stat. |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| |
| namespace clang { |
| class FileManager; |
| |
| /// DirectoryEntry - Cached information about one directory on the disk. |
| /// |
| class DirectoryEntry { |
| const char *Name; // Name of the directory. |
| friend class FileManager; |
| public: |
| DirectoryEntry() : Name(0) {} |
| const char *getName() const { return Name; } |
| }; |
| |
| /// FileEntry - Cached information about one file on the disk. |
| /// |
| class FileEntry { |
| const char *Name; // Name of the file. |
| off_t Size; // File size in bytes. |
| time_t ModTime; // Modification time of file. |
| const DirectoryEntry *Dir; // Directory file lives in. |
| unsigned UID; // A unique (small) ID for the file. |
| dev_t Device; // ID for the device containing the file. |
| ino_t Inode; // Inode number for the file. |
| mode_t FileMode; // The file mode as returned by 'stat'. |
| friend class FileManager; |
| public: |
| FileEntry(dev_t device, ino_t inode, mode_t m) |
| : Name(0), Device(device), Inode(inode), FileMode(m) {} |
| // Add a default constructor for use with llvm::StringMap |
| FileEntry() : Name(0), Device(0), Inode(0), FileMode(0) {} |
| |
| const char *getName() const { return Name; } |
| off_t getSize() const { return Size; } |
| unsigned getUID() const { return UID; } |
| ino_t getInode() const { return Inode; } |
| dev_t getDevice() const { return Device; } |
| time_t getModificationTime() const { return ModTime; } |
| mode_t getFileMode() const { return FileMode; } |
| |
| /// getDir - Return the directory the file lives in. |
| /// |
| const DirectoryEntry *getDir() const { return Dir; } |
| |
| bool operator<(const FileEntry& RHS) const { |
| return Device < RHS.Device || (Device == RHS.Device && Inode < RHS.Inode); |
| } |
| }; |
| |
| /// \brief Abstract interface for introducing a FileManager cache for 'stat' |
| /// system calls, which is used by precompiled and pretokenized headers to |
| /// improve performance. |
| class StatSysCallCache { |
| protected: |
| llvm::OwningPtr<StatSysCallCache> NextStatCache; |
| |
| public: |
| virtual ~StatSysCallCache() {} |
| virtual int stat(const char *path, struct stat *buf) { |
| if (getNextStatCache()) |
| return getNextStatCache()->stat(path, buf); |
| |
| return ::stat(path, buf); |
| } |
| |
| /// \brief Sets the next stat call cache in the chain of stat caches. |
| /// Takes ownership of the given stat cache. |
| void setNextStatCache(StatSysCallCache *Cache) { |
| NextStatCache.reset(Cache); |
| } |
| |
| /// \brief Retrieve the next stat call cache in the chain. |
| StatSysCallCache *getNextStatCache() { return NextStatCache.get(); } |
| |
| /// \brief Retrieve the next stat call cache in the chain, transferring |
| /// ownership of this cache (and, transitively, all of the remaining caches) |
| /// to the caller. |
| StatSysCallCache *takeNextStatCache() { return NextStatCache.take(); } |
| }; |
| |
| /// \brief A stat "cache" that can be used by FileManager to keep |
| /// track of the results of stat() calls that occur throughout the |
| /// execution of the front end. |
| class MemorizeStatCalls : public StatSysCallCache { |
| public: |
| /// \brief The result of a stat() call. |
| /// |
| /// The first member is the result of calling stat(). If stat() |
| /// found something, the second member is a copy of the stat |
| /// structure. |
| typedef std::pair<int, struct stat> StatResult; |
| |
| /// \brief The set of stat() calls that have been |
| llvm::StringMap<StatResult, llvm::BumpPtrAllocator> StatCalls; |
| |
| typedef llvm::StringMap<StatResult, llvm::BumpPtrAllocator>::const_iterator |
| iterator; |
| |
| iterator begin() const { return StatCalls.begin(); } |
| iterator end() const { return StatCalls.end(); } |
| |
| virtual int stat(const char *path, struct stat *buf); |
| }; |
| |
| /// FileManager - Implements support for file system lookup, file system |
| /// caching, and directory search management. This also handles more advanced |
| /// properties, such as uniquing files based on "inode", so that a file with two |
| /// names (e.g. symlinked) will be treated as a single file. |
| /// |
| class FileManager { |
| |
| class UniqueDirContainer; |
| class UniqueFileContainer; |
| |
| /// UniqueDirs/UniqueFiles - Cache for existing directories/files. |
| /// |
| UniqueDirContainer &UniqueDirs; |
| UniqueFileContainer &UniqueFiles; |
| |
| /// DirEntries/FileEntries - This is a cache of directory/file entries we have |
| /// looked up. The actual Entry is owned by UniqueFiles/UniqueDirs above. |
| /// |
| llvm::StringMap<DirectoryEntry*, llvm::BumpPtrAllocator> DirEntries; |
| llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator> FileEntries; |
| |
| /// NextFileUID - Each FileEntry we create is assigned a unique ID #. |
| /// |
| unsigned NextFileUID; |
| |
| /// \brief The virtual files that we have allocated. |
| llvm::SmallVector<FileEntry *, 4> VirtualFileEntries; |
| |
| // Statistics. |
| unsigned NumDirLookups, NumFileLookups; |
| unsigned NumDirCacheMisses, NumFileCacheMisses; |
| |
| // Caching. |
| llvm::OwningPtr<StatSysCallCache> StatCache; |
| |
| int stat_cached(const char* path, struct stat* buf) { |
| return StatCache.get() ? StatCache->stat(path, buf) : stat(path, buf); |
| } |
| |
| public: |
| FileManager(); |
| ~FileManager(); |
| |
| /// \brief Installs the provided StatSysCallCache object within |
| /// the FileManager. |
| /// |
| /// Ownership of this object is transferred to the FileManager. |
| /// |
| /// \param statCache the new stat cache to install. Ownership of this |
| /// object is transferred to the FileManager. |
| /// |
| /// \param AtBeginning whether this new stat cache must be installed at the |
| /// beginning of the chain of stat caches. Otherwise, it will be added to |
| /// the end of the chain. |
| void addStatCache(StatSysCallCache *statCache, bool AtBeginning = false); |
| |
| /// \brief Removes the provided StatSysCallCache object from the file manager. |
| void removeStatCache(StatSysCallCache *statCache); |
| |
| /// getDirectory - Lookup, cache, and verify the specified directory. This |
| /// returns null if the directory doesn't exist. |
| /// |
| const DirectoryEntry *getDirectory(const llvm::StringRef &Filename) { |
| return getDirectory(Filename.begin(), Filename.end()); |
| } |
| const DirectoryEntry *getDirectory(const char *FileStart,const char *FileEnd); |
| |
| /// getFile - Lookup, cache, and verify the specified file. This returns null |
| /// if the file doesn't exist. |
| /// |
| const FileEntry *getFile(const llvm::StringRef &Filename) { |
| return getFile(Filename.begin(), Filename.end()); |
| } |
| const FileEntry *getFile(const char *FilenameStart, |
| const char *FilenameEnd); |
| |
| /// \brief Retrieve a file entry for a "virtual" file that acts as |
| /// if there were a file with the given name on disk. The file |
| /// itself is not accessed. |
| const FileEntry *getVirtualFile(const llvm::StringRef &Filename, |
| off_t Size, time_t ModificationTime); |
| void PrintStats() const; |
| }; |
| |
| } // end namespace clang |
| |
| #endif |