Stage two of getting CFE top correct.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@39734 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 111 insertions, 0 deletions

diff --git a/include/clang/Basic/FileManager.h b/include/clang/Basic/FileManager.h
new file mode 100644
index 0000000000..ad955d7280
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+++ b/include/clang/Basic/FileManager.h
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+//===--- FileManager.h - File System Probing and Caching --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and 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/StringMap.h"
+#include <map>
+#include <string>
+// FIXME: Enhance libsystem to support inode and other fields in stat.
+#include <sys/types.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 directory.
+  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.
+  friend class FileManager;
+public:
+  FileEntry() : Name(0) {}
+  
+  const char *getName() const { return Name; }
+  off_t getSize() const { return Size; }
+  unsigned getUID() const { return UID; }
+  time_t getModificationTime() const { return ModTime; }
+  
+  /// getDir - Return the directory the file lives in.
+  ///
+  const DirectoryEntry *getDir() const { return Dir; }
+};
+
+ 
+/// 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 {
+  /// UniqueDirs/UniqueFiles - Cache from ID's to existing directories/files.
+  ///
+  std::map<std::pair<dev_t, ino_t>, DirectoryEntry> UniqueDirs;
+  std::map<std::pair<dev_t, ino_t>, FileEntry> 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*> DirEntries;
+  llvm::StringMap<FileEntry*> FileEntries;
+  
+  /// NextFileUID - Each FileEntry we create is assigned a unique ID #.
+  ///
+  unsigned NextFileUID;
+  
+  // Statistics.
+  unsigned NumDirLookups, NumFileLookups;
+  unsigned NumDirCacheMisses, NumFileCacheMisses;
+public:
+  FileManager() : DirEntries(64), FileEntries(64), NextFileUID(0) {
+    NumDirLookups = NumFileLookups = 0;
+    NumDirCacheMisses = NumFileCacheMisses = 0;
+  }
+
+  /// getDirectory - Lookup, cache, and verify the specified directory.  This
+  /// returns null if the directory doesn't exist.
+  /// 
+  const DirectoryEntry *getDirectory(const std::string &Filename) {
+    return getDirectory(&Filename[0], &Filename[0] + Filename.size());
+  }
+  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 std::string &Filename) {
+    return getFile(&Filename[0], &Filename[0] + Filename.size());
+  }
+  const FileEntry *getFile(const char *FilenameStart,
+                           const char *FilenameEnd);
+  
+  void PrintStats() const;
+};
+
+}  // end namespace clang
+
+#endif