llvfs.h
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- /**
- * @file llvfs.h
- * @brief Definition of virtual file system
- *
- * $LicenseInfo:firstyear=2002&license=viewergpl$
- *
- * Copyright (c) 2002-2010, Linden Research, Inc.
- *
- * Second Life Viewer Source Code
- * The source code in this file ("Source Code") is provided by Linden Lab
- * to you under the terms of the GNU General Public License, version 2.0
- * ("GPL"), unless you have obtained a separate licensing agreement
- * ("Other License"), formally executed by you and Linden Lab. Terms of
- * the GPL can be found in doc/GPL-license.txt in this distribution, or
- * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
- *
- * There are special exceptions to the terms and conditions of the GPL as
- * it is applied to this Source Code. View the full text of the exception
- * in the file doc/FLOSS-exception.txt in this software distribution, or
- * online at
- * http://secondlifegrid.net/programs/open_source/licensing/flossexception
- *
- * By copying, modifying or distributing this software, you acknowledge
- * that you have read and understood your obligations described above,
- * and agree to abide by those obligations.
- *
- * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
- * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
- * COMPLETENESS OR PERFORMANCE.
- * $/LicenseInfo$
- */
- #ifndef LL_LLVFS_H
- #define LL_LLVFS_H
- #include <deque>
- #include "lluuid.h"
- #include "linked_lists.h"
- #include "llassettype.h"
- #include "llthread.h"
- enum EVFSValid
- {
- VFSVALID_UNKNOWN = 0,
- VFSVALID_OK = 1,
- VFSVALID_BAD_CORRUPT = 2,
- VFSVALID_BAD_CANNOT_OPEN_READONLY = 3,
- VFSVALID_BAD_CANNOT_CREATE = 4
- };
- // Lock types for open vfiles, pending async reads, and pending async appends
- // (There are no async normal writes, currently)
- enum EVFSLock
- {
- VFSLOCK_OPEN = 0,
- VFSLOCK_READ = 1,
- VFSLOCK_APPEND = 2,
- VFSLOCK_COUNT = 3
- };
- // internal classes
- class LLVFSBlock;
- class LLVFSFileBlock;
- class LLVFSFileSpecifier
- {
- public:
- LLVFSFileSpecifier();
- LLVFSFileSpecifier(const LLUUID &file_id, const LLAssetType::EType file_type);
- bool operator<(const LLVFSFileSpecifier &rhs) const;
- bool operator==(const LLVFSFileSpecifier &rhs) const;
- public:
- LLUUID mFileID;
- LLAssetType::EType mFileType;
- };
- class LLVFS
- {
- private:
- // Use createLLVFS() to open a VFS file
- // Pass 0 to not presize
- LLVFS(const std::string& index_filename,
- const std::string& data_filename,
- const BOOL read_only,
- const U32 presize,
- const BOOL remove_after_crash);
- public:
- ~LLVFS();
- // Use this function normally to create LLVFS files
- // Pass 0 to not presize
- static LLVFS * createLLVFS(const std::string& index_filename,
- const std::string& data_filename,
- const BOOL read_only,
- const U32 presize,
- const BOOL remove_after_crash);
- BOOL isValid() const { return (VFSVALID_OK == mValid); }
- EVFSValid getValidState() const { return mValid; }
- // ---------- The following fucntions lock/unlock mDataMutex ----------
- BOOL getExists(const LLUUID &file_id, const LLAssetType::EType file_type);
- S32 getSize(const LLUUID &file_id, const LLAssetType::EType file_type);
- BOOL checkAvailable(S32 max_size);
-
- S32 getMaxSize(const LLUUID &file_id, const LLAssetType::EType file_type);
- BOOL setMaxSize(const LLUUID &file_id, const LLAssetType::EType file_type, S32 max_size);
- void renameFile(const LLUUID &file_id, const LLAssetType::EType file_type,
- const LLUUID &new_id, const LLAssetType::EType &new_type);
- void removeFile(const LLUUID &file_id, const LLAssetType::EType file_type);
- S32 getData(const LLUUID &file_id, const LLAssetType::EType file_type, U8 *buffer, S32 location, S32 length);
- S32 storeData(const LLUUID &file_id, const LLAssetType::EType file_type, const U8 *buffer, S32 location, S32 length);
- void incLock(const LLUUID &file_id, const LLAssetType::EType file_type, EVFSLock lock);
- void decLock(const LLUUID &file_id, const LLAssetType::EType file_type, EVFSLock lock);
- BOOL isLocked(const LLUUID &file_id, const LLAssetType::EType file_type, EVFSLock lock);
- // ----------------------------------------------------------------
- // Used to trigger evil WinXP behavior of "preloading" entire file into memory.
- void pokeFiles();
- // Verify that the index file contents match the in-memory file structure
- // Very slow, do not call routinely. JC
- void audit();
- // Check for uninitialized blocks. Slow, do not call in release. JC
- void checkMem();
- // for debugging, prints a map of the vfs
- void dumpMap();
- void dumpLockCounts();
- void dumpStatistics();
- void listFiles();
- void dumpFiles();
- protected:
- void removeFileBlock(LLVFSFileBlock *fileblock);
-
- void eraseBlockLength(LLVFSBlock *block);
- void eraseBlock(LLVFSBlock *block);
- void addFreeBlock(LLVFSBlock *block);
- //void mergeFreeBlocks();
- void useFreeSpace(LLVFSBlock *free_block, S32 length);
- void sync(LLVFSFileBlock *block, BOOL remove = FALSE);
- void presizeDataFile(const U32 size);
- static LLFILE *openAndLock(const std::string& filename, const char* mode, BOOL read_lock);
- static void unlockAndClose(FILE *fp);
-
- // Can initiate LRU-based file removal to make space.
- // The immune file block will not be removed.
- LLVFSBlock *findFreeBlock(S32 size, LLVFSFileBlock *immune = NULL);
- // lock/unlock data mutex (mDataMutex)
- void lockData() { mDataMutex->lock(); }
- void unlockData() { mDataMutex->unlock(); }
-
- protected:
- LLMutex* mDataMutex;
-
- typedef std::map<LLVFSFileSpecifier, LLVFSFileBlock*> fileblock_map;
- fileblock_map mFileBlocks;
- typedef std::multimap<S32, LLVFSBlock*> blocks_length_map_t;
- blocks_length_map_t mFreeBlocksByLength;
- typedef std::multimap<U32, LLVFSBlock*> blocks_location_map_t;
- blocks_location_map_t mFreeBlocksByLocation;
- LLFILE *mDataFP;
- LLFILE *mIndexFP;
- std::deque<S32> mIndexHoles;
- std::string mIndexFilename;
- std::string mDataFilename;
- BOOL mReadOnly;
- EVFSValid mValid;
- S32 mLockCounts[VFSLOCK_COUNT];
- BOOL mRemoveAfterCrash;
- };
- extern LLVFS *gVFS;
- #endif