1 //===--- FileManager.h - File System Probing and Caching --------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the FileManager interface.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_FILEMANAGER_H
15 #define LLVM_CLANG_FILEMANAGER_H
17 #include "clang/Basic/FileSystemOptions.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/ADT/StringMap.h"
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/ADT/OwningPtr.h"
22 #include "llvm/Support/Allocator.h"
23 #include "llvm/Config/config.h" // for mode_t
24 // FIXME: Enhance libsystem to support inode and other fields in stat.
25 #include <sys/types.h>
31 namespace sys { class Path; }
36 class FileSystemStatCache;
38 /// DirectoryEntry - Cached information about one directory (either on
39 /// the disk or in the virtual file system).
41 class DirectoryEntry {
42 const char *Name; // Name of the directory.
43 friend class FileManager;
45 DirectoryEntry() : Name(0) {}
46 const char *getName() const { return Name; }
49 /// FileEntry - Cached information about one file (either on the disk
50 /// or in the virtual file system). If the 'FD' member is valid, then
51 /// this FileEntry has an open file descriptor for the file.
54 const char *Name; // Name of the file.
55 off_t Size; // File size in bytes.
56 time_t ModTime; // Modification time of file.
57 const DirectoryEntry *Dir; // Directory file lives in.
58 unsigned UID; // A unique (small) ID for the file.
59 dev_t Device; // ID for the device containing the file.
60 ino_t Inode; // Inode number for the file.
61 mode_t FileMode; // The file mode as returned by 'stat'.
63 /// FD - The file descriptor for the file entry if it is opened and owned
64 /// by the FileEntry. If not, this is set to -1.
66 friend class FileManager;
69 FileEntry(dev_t device, ino_t inode, mode_t m)
70 : Name(0), Device(device), Inode(inode), FileMode(m), FD(-1) {}
71 // Add a default constructor for use with llvm::StringMap
72 FileEntry() : Name(0), Device(0), Inode(0), FileMode(0), FD(-1) {}
74 FileEntry(const FileEntry &FE) {
75 memcpy(this, &FE, sizeof(FE));
76 assert(FD == -1 && "Cannot copy a file-owning FileEntry");
79 void operator=(const FileEntry &FE) {
80 memcpy(this, &FE, sizeof(FE));
81 assert(FD == -1 && "Cannot assign a file-owning FileEntry");
86 const char *getName() const { return Name; }
87 off_t getSize() const { return Size; }
88 unsigned getUID() const { return UID; }
89 ino_t getInode() const { return Inode; }
90 dev_t getDevice() const { return Device; }
91 time_t getModificationTime() const { return ModTime; }
92 mode_t getFileMode() const { return FileMode; }
94 /// getDir - Return the directory the file lives in.
96 const DirectoryEntry *getDir() const { return Dir; }
98 bool operator<(const FileEntry &RHS) const {
99 return Device < RHS.Device || (Device == RHS.Device && Inode < RHS.Inode);
103 /// FileManager - Implements support for file system lookup, file system
104 /// caching, and directory search management. This also handles more advanced
105 /// properties, such as uniquing files based on "inode", so that a file with two
106 /// names (e.g. symlinked) will be treated as a single file.
109 FileSystemOptions FileSystemOpts;
111 class UniqueDirContainer;
112 class UniqueFileContainer;
114 /// UniqueRealDirs/UniqueRealFiles - Cache for existing real directories/files.
116 UniqueDirContainer &UniqueRealDirs;
117 UniqueFileContainer &UniqueRealFiles;
119 /// \brief The virtual directories that we have allocated. For each
120 /// virtual file (e.g. foo/bar/baz.cpp), we add all of its parent
121 /// directories (foo/ and foo/bar/) here.
122 llvm::SmallVector<DirectoryEntry*, 4> VirtualDirectoryEntries;
123 /// \brief The virtual files that we have allocated.
124 llvm::SmallVector<FileEntry*, 4> VirtualFileEntries;
126 /// SeenDirEntries/SeenFileEntries - This is a cache that maps paths
127 /// to directory/file entries (either real or virtual) we have
128 /// looked up. The actual Entries for real directories/files are
129 /// owned by UniqueRealDirs/UniqueRealFiles above, while the Entries
130 /// for virtual directories/files are owned by
131 /// VirtualDirectoryEntries/VirtualFileEntries above.
133 llvm::StringMap<DirectoryEntry*, llvm::BumpPtrAllocator> SeenDirEntries;
134 llvm::StringMap<FileEntry*, llvm::BumpPtrAllocator> SeenFileEntries;
136 /// NextFileUID - Each FileEntry we create is assigned a unique ID #.
138 unsigned NextFileUID;
141 unsigned NumDirLookups, NumFileLookups;
142 unsigned NumDirCacheMisses, NumFileCacheMisses;
145 llvm::OwningPtr<FileSystemStatCache> StatCache;
147 bool getStatValue(const char *Path, struct stat &StatBuf,
148 int *FileDescriptor);
150 /// Add all ancestors of the given path (pointing to either a file
151 /// or a directory) as virtual directories.
152 void addAncestorsAsVirtualDirs(llvm::StringRef Path);
155 FileManager(const FileSystemOptions &FileSystemOpts);
158 /// \brief Installs the provided FileSystemStatCache object within
161 /// Ownership of this object is transferred to the FileManager.
163 /// \param statCache the new stat cache to install. Ownership of this
164 /// object is transferred to the FileManager.
166 /// \param AtBeginning whether this new stat cache must be installed at the
167 /// beginning of the chain of stat caches. Otherwise, it will be added to
168 /// the end of the chain.
169 void addStatCache(FileSystemStatCache *statCache, bool AtBeginning = false);
171 /// \brief Removes the specified FileSystemStatCache object from the manager.
172 void removeStatCache(FileSystemStatCache *statCache);
174 /// getDirectory - Lookup, cache, and verify the specified directory
175 /// (real or virtual). This returns NULL if the directory doesn't exist.
177 const DirectoryEntry *getDirectory(llvm::StringRef DirName);
179 /// \brief Lookup, cache, and verify the specified file (real or
180 /// virtual). This returns NULL if the file doesn't exist.
182 /// \param openFile if true and the file exists, it will be opened.
183 const FileEntry *getFile(llvm::StringRef Filename, bool openFile = false);
185 /// \brief Retrieve a file entry for a "virtual" file that acts as
186 /// if there were a file with the given name on disk. The file
187 /// itself is not accessed.
188 const FileEntry *getVirtualFile(llvm::StringRef Filename, off_t Size,
189 time_t ModificationTime);
191 /// \brief Open the specified file as a MemoryBuffer, returning a new
192 /// MemoryBuffer if successful, otherwise returning null.
193 llvm::MemoryBuffer *getBufferForFile(const FileEntry *Entry,
194 std::string *ErrorStr = 0);
195 llvm::MemoryBuffer *getBufferForFile(llvm::StringRef Filename,
196 std::string *ErrorStr = 0);
198 // getNoncachedStatValue - Will get the 'stat' information for the given path.
199 // If the path is relative, it will be resolved against the WorkingDir of the
200 // FileManager's FileSystemOptions.
201 bool getNoncachedStatValue(llvm::StringRef Path, struct stat &StatBuf);
203 /// \brief If path is not absolute and FileSystemOptions set the working
204 /// directory, the path is modified to be relative to the given
205 /// working directory.
206 void FixupRelativePath(llvm::SmallVectorImpl<char> &path) const;
208 /// \brief Produce an array mapping from the unique IDs assigned to each
209 /// file to the corresponding FileEntry pointer.
210 void GetUniqueIDMapping(
211 llvm::SmallVectorImpl<const FileEntry *> &UIDToFiles) const;
213 void PrintStats() const;
216 } // end namespace clang