This changeset hooks up many things that have been in progress and moves things about between llfilesystem and lldiskcache - there is still some bookkeeping work left but this is the first version that appears to work and actively manage the cache

6 files changed, 307 insertions, 270 deletions

diff --git a/indra/llfilesystem/lldiskcache.cpp b/indra/llfilesystem/lldiskcache.cpp
index 4b2ba0dd79..4b82cf3cce 100644
--- a/indra/llfilesystem/lldiskcache.cpp
+++ b/indra/llfilesystem/lldiskcache.cpp
@@ -25,41 +25,31 @@
  */
 
 #include "linden_common.h"
-#include "lluuid.h"
+#include "llassettype.h"
 #include "lldir.h"
-
-#include "lldiskcache.h"
-
 #include <boost/filesystem.hpp>
 #include <boost/range/iterator_range.hpp>
-
 #include <chrono>
-#include <thread>
-#include <algorithm>
 
-LLDiskCache::LLDiskCache(const std::string cache_dir) :
+#include "lldiskcache.h"
+
+LLDiskCache::LLDiskCache(const std::string cache_dir,
+                         const int max_size_bytes,
+                         const bool enable_cache_debug_info) :
     mCacheDir(cache_dir),
-    mMaxSizeBytes(mDefaultSizeBytes)
+    mMaxSizeBytes(max_size_bytes),
+    mEnableCacheDebugInfo(enable_cache_debug_info)
 {
-    // no access to LLControlGroup / gSavedSettings so use the system environment
-    // to trigger additional debugging on top of the default "we purged the cache"
-    mCacheDebugInfo = true;
-    if (getenv("LL_CACHE_DEBUGGING") != nullptr)
-    {
-        mCacheDebugInfo = true;
-    }
+    // the prefix used for cache filenames to disambiguate them from other files
+    mCacheFilenamePrefix = "sl_cache";
 
     // create cache dir if it does not exist
     boost::filesystem::create_directory(cache_dir);
 }
 
-LLDiskCache::~LLDiskCache()
-{
-}
-
 void LLDiskCache::purge()
 {
-    if (mCacheDebugInfo)
+    if (mEnableCacheDebugInfo)
     {
         LL_INFOS() << "Total dir size before purge is " << dirFileSize(mCacheDir) << LL_ENDL;
     }
@@ -75,11 +65,14 @@ void LLDiskCache::purge()
         {
             if (boost::filesystem::is_regular_file(entry))
             {
-                uintmax_t file_size = boost::filesystem::file_size(entry);
-                const std::string file_path = entry.path().string();
-                const std::time_t file_time = boost::filesystem::last_write_time(entry);
+                if (entry.path().string().find(mCacheFilenamePrefix) != std::string::npos)
+                {
+                    uintmax_t file_size = boost::filesystem::file_size(entry);
+                    const std::string file_path = entry.path().string();
+                    const std::time_t file_time = boost::filesystem::last_write_time(entry);
 
-                file_info.push_back(file_info_t(file_time, { file_size, file_path }));
+                    file_info.push_back(file_info_t(file_time, { file_size, file_path }));
+                }
             }
         }
     }
@@ -107,7 +100,7 @@ void LLDiskCache::purge()
             action = "  KEEP:";
         }
 
-        if (mCacheDebugInfo)
+        if (mEnableCacheDebugInfo)
         {
             // have to do this because of LL_INFO/LL_END weirdness
             std::ostringstream line;
@@ -121,7 +114,7 @@ void LLDiskCache::purge()
         }
     }
 
-    if (mCacheDebugInfo)
+    if (mEnableCacheDebugInfo)
     {
         auto end_time = std::chrono::high_resolution_clock::now();
         auto execute_time = std::chrono::duration_cast<std::chrono::milliseconds>(end_time - start_time).count();
@@ -130,9 +123,78 @@ void LLDiskCache::purge()
     }
 }
 
+const std::string LLDiskCache::assetTypeToString(LLAssetType::EType at)
+{
+    /**
+     * Make use of the C++17 (or is it 14) feature that allows
+     * for inline initialization of an std::map<>
+     */
+    typedef std::map<LLAssetType::EType, std::string> asset_type_to_name_t;
+    asset_type_to_name_t asset_type_to_name =
+    {
+        { LLAssetType::AT_TEXTURE, "TEXTURE" },
+        { LLAssetType::AT_SOUND, "SOUND" },
+        { LLAssetType::AT_CALLINGCARD, "CALLINGCARD" },
+        { LLAssetType::AT_LANDMARK, "LANDMARK" },
+        { LLAssetType::AT_SCRIPT, "SCRIPT" },
+        { LLAssetType::AT_CLOTHING, "CLOTHING" },
+        { LLAssetType::AT_OBJECT, "OBJECT" },
+        { LLAssetType::AT_NOTECARD, "NOTECARD" },
+        { LLAssetType::AT_CATEGORY, "CATEGORY" },
+        { LLAssetType::AT_LSL_TEXT, "LSL_TEXT" },
+        { LLAssetType::AT_LSL_BYTECODE, "LSL_BYTECODE" },
+        { LLAssetType::AT_TEXTURE_TGA, "TEXTURE_TGA" },
+        { LLAssetType::AT_BODYPART, "BODYPART" },
+        { LLAssetType::AT_SOUND_WAV, "SOUND_WAV" },
+        { LLAssetType::AT_IMAGE_TGA, "IMAGE_TGA" },
+        { LLAssetType::AT_IMAGE_JPEG, "IMAGE_JPEG" },
+        { LLAssetType::AT_ANIMATION, "ANIMATION" },
+        { LLAssetType::AT_GESTURE, "GESTURE" },
+        { LLAssetType::AT_SIMSTATE, "SIMSTATE" },
+        { LLAssetType::AT_LINK, "LINK" },
+        { LLAssetType::AT_LINK_FOLDER, "LINK_FOLDER" },
+        { LLAssetType::AT_MARKETPLACE_FOLDER, "MARKETPLACE_FOLDER" },
+        { LLAssetType::AT_WIDGET, "WIDGET" },
+        { LLAssetType::AT_PERSON, "PERSON" },
+        { LLAssetType::AT_MESH, "MESH" },
+        { LLAssetType::AT_SETTINGS, "SETTINGS" },
+        { LLAssetType::AT_UNKNOWN, "UNKNOWN" }
+    };
+
+    asset_type_to_name_t::iterator iter = asset_type_to_name.find(at);
+    if (iter != asset_type_to_name.end())
+    {
+        return iter->second;
+    }
+
+    return std::string("UNKNOWN");
+}
+
+const std::string LLDiskCache::metaDataToFilepath(const std::string id,
+        LLAssetType::EType at,
+        const std::string extra_info)
+{
+    std::ostringstream file_path;
+
+    file_path << mCacheDir;
+    file_path << gDirUtilp->getDirDelimiter();
+    file_path << mCacheFilenamePrefix;
+    file_path << "_";
+    file_path << id;
+    file_path << "_";
+    file_path << (extra_info.empty() ? "0" : extra_info);
+    file_path << "_";
+    file_path << assetTypeToString(at);
+    file_path << ".asset";
+
+    LL_INFOS() << "filepath.str() = " << file_path.str() << LL_ENDL;
+
+    return file_path.str();
+}
+
 /**
- * Update the "last write time" of a file to "now". This must be called whenever a 
- * file in the cache is read (not written) so that the last time the file was 
+ * Update the "last write time" of a file to "now". This must be called whenever a
+ * file in the cache is read (not written) so that the last time the file was
  * accessed which is used in the mechanism for purging the cache, is up to date.
  */
 void LLDiskCache::updateFileAccessTime(const std::string file_path)
@@ -144,8 +206,8 @@ void LLDiskCache::updateFileAccessTime(const std::string file_path)
 /**
  * Clear the cache by removing all the files in the cache directory
  * individually. It's important to maintain control of which directory
- * if passed in and not let the user inadvertently (or maliciously) set 
- * it to an random location like your project source or OS system directory 
+ * if passed in and not let the user inadvertently (or maliciously) set
+ * it to an random location like your project source or OS system directory
  */
 void LLDiskCache::clearCache(const std::string cache_dir)
 {
@@ -155,7 +217,10 @@ void LLDiskCache::clearCache(const std::string cache_dir)
         {
             if (boost::filesystem::is_regular_file(entry))
             {
-                boost::filesystem::remove(entry);
+                if (entry.path().string().find(mCacheFilenamePrefix) != std::string::npos)
+                {
+                    boost::filesystem::remove(entry);
+                }
             }
         }
     }
@@ -181,7 +246,10 @@ uintmax_t LLDiskCache::dirFileSize(const std::string dir)
         {
             if (boost::filesystem::is_regular_file(entry))
             {
-                total_file_size += boost::filesystem::file_size(entry);
+                if (entry.path().string().find(mCacheFilenamePrefix) != std::string::npos)
+                {
+                    total_file_size += boost::filesystem::file_size(entry);
+                }
             }
         }
     }
diff --git a/indra/llfilesystem/lldiskcache.h b/indra/llfilesystem/lldiskcache.h
index 1618cec6a6..12599a132e 100644
--- a/indra/llfilesystem/lldiskcache.h
+++ b/indra/llfilesystem/lldiskcache.h
@@ -27,15 +27,50 @@
 #ifndef _LLDISKCACHE
 #define _LLDISKCACHE
 
-class LLDiskCache
+#include "llsingleton.h"
+
+class LLDiskCache :
+    public LLParamSingleton<LLDiskCache>
 {
     public:
-        LLDiskCache(const std::string cache_dir);
-        ~LLDiskCache();
+        LLSINGLETON(LLDiskCache,
+                    const std::string cache_dir,
+                    const int max_size_bytes,
+                    const bool enable_cache_debug_info);
+        virtual ~LLDiskCache() = default;
+
+    public:
+        ///**
+        // * The location of the cache dir is set in llappviewer at startup via the
+        // * saved settings parameters.  We do not have access to those saved settings
+        // * here in LLCommon so we must provide an accessor for other classes to use
+        // * when they need it - e.g. LLFilesystem needs the path so it can write files
+        // * to it.
+        // */
+        //const std::string getCacheDirName() { return mCacheDir; }
+
+        ///**
+        // * Each cache filename has a prefix inserted (see definition of the
+        // * mCacheFilenamePrefix variable below for why) but the LLFileSystem
+        // * component needs access to it to in order to create the file so we
+        // * expose it by a getter here.
+        // */
+        //const std::string getCacheFilenamePrefix() { return mCacheFilenamePrefix; }
 
         /**
-         * Update the "last write time" of a file to "now". This must be called whenever a 
-         * file in the cache is read (not written) so that the last time the file was 
+         * Construct a filename and path to it based on the file meta data
+         * (id, asset type, additional 'extra' info like discard level perhaps)
+         * Worth pointing out that this function used to be in LLFileSystem but
+         * so many things had to be pushed back there to accomodate it, that I
+         * decided to move it here.  Still not sure that's completely right.
+         */
+        const std::string metaDataToFilepath(const std::string id,
+                                             LLAssetType::EType at,
+                                             const std::string extra_info);
+
+        /**
+         * Update the "last write time" of a file to "now". This must be called whenever a
+         * file in the cache is read (not written) so that the last time the file was
          * accessed which is used in the mechanism for purging the cache, is up to date.
          */
         void updateFileAccessTime(const std::string file_path);
@@ -51,28 +86,26 @@ class LLDiskCache
          */
         void clearCache(const std::string cache_dir);
 
-        /**
-         * Manage max size in bytes of cache - use a discrete setter/getter so the value can
-         * be changed in the preferences and cache cleared/purged without restarting viewer
-         * to instantiate this class again.
-         */
-        void setMaxSizeBytes(const uintmax_t size_bytes) { mMaxSizeBytes = size_bytes; }
-        uintmax_t getMaxSizeBytes() const { return mMaxSizeBytes; }
-
     private:
         /**
          * Utility function to gather the total size the files in a given
-         * directory. Primarily used here to determine the directory size 
+         * directory. Primarily used here to determine the directory size
          * before and after the cache purge
          */
         uintmax_t dirFileSize(const std::string dir);
 
+        /**
+         * Utility function to convert an LLAssetType enum into a
+         * string that we use as part of the cache file filename
+         */
+        const std::string assetTypeToString(LLAssetType::EType at);
+
     private:
         /**
-         * Default of 20MB seems reasonable - it will likely be reset
-         * immediately anyway using a value from the Viewer settings
+         * The maximum size of the cache in bytes. After purge is called, the
+         * total size of the cache files in the cache directory will be
+         * less than this value
          */
-        const uintmax_t mDefaultSizeBytes = 20 * 1024 * 1024;
         uintmax_t mMaxSizeBytes;
 
         /**
@@ -84,11 +117,20 @@ class LLDiskCache
         std::string mCacheDir;
 
         /**
-         * This is set from the CacheDebugInfo global setting and
-         * when enabled, displays additional debugging information in
+         * The prefix inserted at the start of a cache file filename to
+         * help identify it as a cache file. It's probably not required
+         * (just the presence in the cache folder is enough) but I am
+         * paranoid about the cache folder being set to something bad
+         * like the users' OS system dir by mistake or maliciously and
+         * this will help to offset any damage if that happens.
+         */
+        std::string mCacheFilenamePrefix;
+
+        /**
+         * When enabled, displays additional debugging information in
          * various parts of the code
          */
-        bool mCacheDebugInfo;
+        bool mEnableCacheDebugInfo;
 };
 
 #endif // _LLDISKCACHE
diff --git a/indra/llfilesystem/llfilesystem.cpp b/indra/llfilesystem/llfilesystem.cpp
index 6d6ff3d7e1..c6b20caa69 100644
--- a/indra/llfilesystem/llfilesystem.cpp
+++ b/indra/llfilesystem/llfilesystem.cpp
@@ -1,4 +1,4 @@
-/** 
+/**
  * @file filesystem.h
  * @brief Simulate local file system operations.
  * @Note The initial implementation does actually use standard C++
@@ -8,21 +8,21 @@
  * $LicenseInfo:firstyear=2002&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2010, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -36,139 +36,74 @@
 
 #include <fstream>
 
-const S32 LLFileSystem::READ		= 0x00000001;
-const S32 LLFileSystem::WRITE		= 0x00000002;
-const S32 LLFileSystem::READ_WRITE	= 0x00000003;  // LLFileSystem::READ & LLFileSystem::WRITE
-const S32 LLFileSystem::APPEND		= 0x00000006;  // 0x00000004 & LLFileSystem::WRITE
+const S32 LLFileSystem::READ        = 0x00000001;
+const S32 LLFileSystem::WRITE       = 0x00000002;
+const S32 LLFileSystem::READ_WRITE  = 0x00000003;  // LLFileSystem::READ & LLFileSystem::WRITE
+const S32 LLFileSystem::APPEND      = 0x00000006;  // 0x00000004 & LLFileSystem::WRITE
 
 static LLTrace::BlockTimerStatHandle FTM_VFILE_WAIT("VFile Wait");
-LLDiskCache* LLFileSystem::mDiskCache = 0;
-std::string LLFileSystem::mCacheDirName = "cache";
 
-LLFileSystem::LLFileSystem(const LLUUID &file_id, const LLAssetType::EType file_type, S32 mode)
+LLFileSystem::LLFileSystem(const LLUUID& file_id, const LLAssetType::EType file_type, S32 mode)
 {
-	mFileType =	file_type;
-	mFileID = file_id;
-	mPosition = 0;
+    mFileType = file_type;
+    mFileID = file_id;
+    mPosition = 0;
     mBytesRead = 0;
-    mReadComplete = FALSE;
-	mMode = mode;
+    mMode = mode;
 }
 
 LLFileSystem::~LLFileSystem()
 {
 }
 
-const std::string assetTypeToString(LLAssetType::EType at)
+// static
+bool LLFileSystem::getExists(const LLUUID& file_id, const LLAssetType::EType file_type)
 {
-    /**
-     * Make use of the C++17 (or is it 14) feature that allows
-     * for inline initialization of an std::map<>
-     */
-    typedef std::map<LLAssetType::EType, std::string> asset_type_to_name_t;
-    asset_type_to_name_t asset_type_to_name =
-    {
-        { LLAssetType::AT_TEXTURE, "TEXTURE" },
-        { LLAssetType::AT_SOUND, "SOUND" },
-        { LLAssetType::AT_CALLINGCARD, "CALLINGCARD" },
-        { LLAssetType::AT_LANDMARK, "LANDMARK" },
-        { LLAssetType::AT_SCRIPT, "SCRIPT" },
-        { LLAssetType::AT_CLOTHING, "CLOTHING" },
-        { LLAssetType::AT_OBJECT, "OBJECT" },
-        { LLAssetType::AT_NOTECARD, "NOTECARD" },
-        { LLAssetType::AT_CATEGORY, "CATEGORY" },
-        { LLAssetType::AT_LSL_TEXT, "LSL_TEXT" },
-        { LLAssetType::AT_LSL_BYTECODE, "LSL_BYTECODE" },
-        { LLAssetType::AT_TEXTURE_TGA, "TEXTURE_TGA" },
-        { LLAssetType::AT_BODYPART, "BODYPART" },
-        { LLAssetType::AT_SOUND_WAV, "SOUND_WAV" },
-        { LLAssetType::AT_IMAGE_TGA, "IMAGE_TGA" },
-        { LLAssetType::AT_IMAGE_JPEG, "IMAGE_JPEG" },
-        { LLAssetType::AT_ANIMATION, "ANIMATION" },
-        { LLAssetType::AT_GESTURE, "GESTURE" },
-        { LLAssetType::AT_SIMSTATE, "SIMSTATE" },
-        { LLAssetType::AT_LINK, "LINK" },
-        { LLAssetType::AT_LINK_FOLDER, "LINK_FOLDER" },
-        { LLAssetType::AT_MARKETPLACE_FOLDER, "MARKETPLACE_FOLDER" },
-        { LLAssetType::AT_WIDGET, "WIDGET" },
-        { LLAssetType::AT_PERSON, "PERSON" },
-        { LLAssetType::AT_MESH, "MESH" },
-        { LLAssetType::AT_SETTINGS, "SETTINGS" },
-        { LLAssetType::AT_UNKNOWN, "UNKNOWN" }
-    };
-
-    asset_type_to_name_t::iterator iter = asset_type_to_name.find(at);
-    if (iter != asset_type_to_name.end())
+    std::string id_str;
+    file_id.toString(id_str);
+    const std::string extra_info = "";
+    const std::string filename = LLDiskCache::getInstance()->metaDataToFilepath(id_str, file_type, extra_info);
+
+    std::ifstream file(filename, std::ios::binary);
+    if (file.is_open())
     {
-        return iter->second;
+        file.seekg(0, std::ios::end);
+        return file.tellg() > 0;
     }
-
-    return std::string("UNKNOWN");
-}
-
-const std::string LLFileSystem::idToFilepath(const std::string id, LLAssetType::EType at)
-{
-    /**
-     * For the moment this is just {UUID}_{ASSET_TYPE}.txt but of
-     * course,  will be greatly expanded upon
-     */
-    std::ostringstream ss;
-    ss << "00cache_";
-    ss << id;
-    ss << "_";
-    ss << assetTypeToString(at);
-    ss << ".txt";
-
-    const std::string filepath = gDirUtilp->getExpandedFilename(LL_PATH_CACHE, mCacheDirName, ss.str());
-
-    return filepath;
+    return false;
 }
 
 // static
-bool LLFileSystem::getExists(const LLUUID &file_id, const LLAssetType::EType file_type)
-{
-	std::string id_str;
-	file_id.toString(id_str);
-	const std::string filename = idToFilepath(id_str, file_type);
-
-	std::ifstream file(filename, std::ios::binary);
-	if (file.is_open())
-	{
-		file.seekg(0, std::ios::end);
-		return file.tellg() > 0;
-	}
-	return false;
-}
-
-// static
-bool LLFileSystem::removeFile(const LLUUID &file_id, const LLAssetType::EType file_type)
+bool LLFileSystem::removeFile(const LLUUID& file_id, const LLAssetType::EType file_type)
 {
     std::string id_str;
     file_id.toString(id_str);
-    const std::string filename = idToFilepath(id_str, file_type);
-    
+    const std::string extra_info = "";
+    const std::string filename =  LLDiskCache::getInstance()->metaDataToFilepath(id_str, file_type, extra_info);
+
     std::remove(filename.c_str());
 
     return true;
 }
 
 // static
-bool LLFileSystem::renameFile(const LLUUID &old_file_id, const LLAssetType::EType old_file_type,
-                         const LLUUID &new_file_id, const LLAssetType::EType new_file_type)
+bool LLFileSystem::renameFile(const LLUUID& old_file_id, const LLAssetType::EType old_file_type,
+                              const LLUUID& new_file_id, const LLAssetType::EType new_file_type)
 {
     std::string old_id_str;
     old_file_id.toString(old_id_str);
-    const std::string old_filename = idToFilepath(old_id_str, old_file_type);
+    const std::string extra_info = "";
+    const std::string old_filename =  LLDiskCache::getInstance()->metaDataToFilepath(old_id_str, old_file_type, extra_info);
 
     std::string new_id_str;
     new_file_id.toString(new_id_str);
-    const std::string new_filename = idToFilepath(new_id_str, new_file_type);
+    const std::string new_filename =  LLDiskCache::getInstance()->metaDataToFilepath(new_id_str, new_file_type, extra_info);
 
     if (std::rename(old_filename.c_str(), new_filename.c_str()))
     {
         // We would like to return FALSE here indicating the operation
         // failed but the original code does not and doing so seems to
-        // break a lot of things so we go with the flow... 
+        // break a lot of things so we go with the flow...
         //return FALSE;
     }
 
@@ -176,11 +111,12 @@ bool LLFileSystem::renameFile(const LLUUID &old_file_id, const LLAssetType::ETyp
 }
 
 // static
-S32 LLFileSystem::getFileSize(const LLUUID &file_id, const LLAssetType::EType file_type)
+S32 LLFileSystem::getFileSize(const LLUUID& file_id, const LLAssetType::EType file_type)
 {
     std::string id_str;
     file_id.toString(id_str);
-    const std::string filename = idToFilepath(id_str, file_type);
+    const std::string extra_info = "";
+    const std::string filename =  LLDiskCache::getInstance()->metaDataToFilepath(id_str, file_type, extra_info);
 
     S32 file_size = 0;
     std::ifstream file(filename, std::ios::binary);
@@ -193,15 +129,14 @@ S32 LLFileSystem::getFileSize(const LLUUID &file_id, const LLAssetType::EType fi
     return file_size;
 }
 
-BOOL LLFileSystem::read(U8 *buffer, S32 bytes, BOOL async, F32 priority)
+BOOL LLFileSystem::read(U8* buffer, S32 bytes)
 {
-	BOOL success = TRUE;
-
-    mReadComplete = FALSE;
+    BOOL success = TRUE;
 
     std::string id;
     mFileID.toString(id);
-    const std::string filename = idToFilepath(id, mFileType);
+    const std::string extra_info = "";
+    const std::string filename =  LLDiskCache::getInstance()->metaDataToFilepath(id, mFileType, extra_info);
 
     std::ifstream file(filename, std::ios::binary);
     if (file.is_open())
@@ -226,44 +161,33 @@ BOOL LLFileSystem::read(U8 *buffer, S32 bytes, BOOL async, F32 priority)
         {
             success = FALSE;
         }
-
-        mReadComplete = TRUE;
     }
 
-    // update the last access time for the file - this is required 
+    // update the last access time for the file - this is required
     // even though we are reading and not writing because this is the
     // way the cache works - it relies on a valid "last accessed time" for
     // each file so it knows how to remove the oldest, unused files
-    LLFileSystem::mDiskCache->updateFileAccessTime(filename);
+    LLDiskCache::getInstance()->updateFileAccessTime(filename);
 
     return success;
 }
 
-BOOL LLFileSystem::isReadComplete()
-{
-    if (mReadComplete)
-    {
-        return TRUE;
-    }
-
-    return FALSE;
-}
-
 S32 LLFileSystem::getLastBytesRead()
 {
-	return mBytesRead;
+    return mBytesRead;
 }
 
 BOOL LLFileSystem::eof()
 {
-	return mPosition >= getSize();
+    return mPosition >= getSize();
 }
 
-BOOL LLFileSystem::write(const U8 *buffer, S32 bytes)
+BOOL LLFileSystem::write(const U8* buffer, S32 bytes)
 {
     std::string id_str;
     mFileID.toString(id_str);
-    const std::string filename = idToFilepath(id_str, mFileType);
+    const std::string extra_info = "";
+    const std::string filename =  LLDiskCache::getInstance()->metaDataToFilepath(id_str, mFileType, extra_info);
 
     BOOL success = FALSE;
 
@@ -295,37 +219,37 @@ BOOL LLFileSystem::write(const U8 *buffer, S32 bytes)
 
 BOOL LLFileSystem::seek(S32 offset, S32 origin)
 {
-	if (-1 == origin)
-	{
-		origin = mPosition;
-	}
+    if (-1 == origin)
+    {
+        origin = mPosition;
+    }
 
-	S32 new_pos = origin + offset;
+    S32 new_pos = origin + offset;
 
-	S32 size = getSize();
+    S32 size = getSize();
 
-	if (new_pos > size)
-	{
-		LL_WARNS() << "Attempt to seek past end of file" << LL_ENDL;
+    if (new_pos > size)
+    {
+        LL_WARNS() << "Attempt to seek past end of file" << LL_ENDL;
 
-		mPosition = size;
-		return FALSE;
-	}
-	else if (new_pos < 0)
-	{
-		LL_WARNS() << "Attempt to seek past beginning of file" << LL_ENDL;
+        mPosition = size;
+        return FALSE;
+    }
+    else if (new_pos < 0)
+    {
+        LL_WARNS() << "Attempt to seek past beginning of file" << LL_ENDL;
 
-		mPosition = 0;
-		return FALSE;
-	}
+        mPosition = 0;
+        return FALSE;
+    }
 
-	mPosition = new_pos;
-	return TRUE;
+    mPosition = new_pos;
+    return TRUE;
 }
 
 S32 LLFileSystem::tell() const
 {
-	return mPosition;
+    return mPosition;
 }
 
 S32 LLFileSystem::getSize()
@@ -335,11 +259,11 @@ S32 LLFileSystem::getSize()
 
 S32 LLFileSystem::getMaxSize()
 {
-    // offer up a huge size since we don't care what the max is 
+    // offer up a huge size since we don't care what the max is
     return INT_MAX;
 }
 
-BOOL LLFileSystem::rename(const LLUUID &new_id, const LLAssetType::EType new_type)
+BOOL LLFileSystem::rename(const LLUUID& new_id, const LLAssetType::EType new_type)
 {
     LLFileSystem::renameFile(mFileID, mFileType, new_id, new_type);
 
@@ -355,19 +279,3 @@ BOOL LLFileSystem::remove()
 
     return TRUE;
 }
-
-// static
-void LLFileSystem::initClass()
-{
-    const std::string cache_dir = gDirUtilp->getExpandedFilename(LL_PATH_CACHE, mCacheDirName);
-
-    LLFileSystem::mDiskCache = new LLDiskCache(cache_dir);
-
-    mDiskCache->purge();
-}
-
-// static
-void LLFileSystem::cleanupClass()
-{
-    delete LLFileSystem::mDiskCache;
-}
diff --git a/indra/llfilesystem/llfilesystem.h b/indra/llfilesystem/llfilesystem.h
index 5d87de9bf8..46bf1bd775 100644
--- a/indra/llfilesystem/llfilesystem.h
+++ b/indra/llfilesystem/llfilesystem.h
@@ -1,5 +1,5 @@
-/** 
-/** 
+/**
+/**
  * @file filesystem.h
  * @brief Simulate local file system operations.
  * @Note The initial implementation does actually use standard C++
@@ -9,21 +9,21 @@
  * $LicenseInfo:firstyear=2002&license=viewerlgpl$
  * Second Life Viewer Source Code
  * Copyright (C) 2010, Linden Research, Inc.
- * 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation;
  * version 2.1 of the License only.
- * 
+ *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
- * 
+ *
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
@@ -37,51 +37,43 @@
 
 class LLFileSystem
 {
-public:
-	LLFileSystem(const LLUUID &file_id, const LLAssetType::EType file_type, S32 mode = LLFileSystem::READ);
-	~LLFileSystem();
+    public:
+        LLFileSystem(const LLUUID& file_id, const LLAssetType::EType file_type, S32 mode = LLFileSystem::READ);
+        ~LLFileSystem();
 
-	BOOL read(U8 *buffer, S32 bytes, BOOL async = FALSE, F32 priority = 128.f);	/* Flawfinder: ignore */ 
-	BOOL isReadComplete();
-	S32  getLastBytesRead();
-	BOOL eof();
+        BOOL read(U8* buffer, S32 bytes);
+        S32  getLastBytesRead();
+        BOOL eof();
 
-	BOOL write(const U8 *buffer, S32 bytes);
-	BOOL seek(S32 offset, S32 origin = -1);
-	S32  tell() const;
+        BOOL write(const U8* buffer, S32 bytes);
+        BOOL seek(S32 offset, S32 origin = -1);
+        S32  tell() const;
 
-	S32 getSize();
-	S32 getMaxSize();
-	BOOL rename(const LLUUID &new_id, const LLAssetType::EType new_type);
-	BOOL remove();
+        S32 getSize();
+        S32 getMaxSize();
+        BOOL rename(const LLUUID& new_id, const LLAssetType::EType new_type);
+        BOOL remove();
 
-    static bool getExists(const LLUUID &file_id, const LLAssetType::EType file_type);
-    static bool removeFile(const LLUUID &file_id, const LLAssetType::EType file_type);
-    static bool renameFile(const LLUUID &old_file_id, const LLAssetType::EType old_file_type,
-                           const LLUUID &new_file_id, const LLAssetType::EType new_file_type);
-    static S32 getFileSize(const LLUUID &file_id, const LLAssetType::EType file_type);
-	
-	static void initClass();
-	static void cleanupClass();
+        static bool getExists(const LLUUID& file_id, const LLAssetType::EType file_type);
+        static bool removeFile(const LLUUID& file_id, const LLAssetType::EType file_type);
+        static bool renameFile(const LLUUID& old_file_id, const LLAssetType::EType old_file_type,
+                               const LLUUID& new_file_id, const LLAssetType::EType new_file_type);
+        static S32 getFileSize(const LLUUID& file_id, const LLAssetType::EType file_type);
 
-public:
-	static const S32 READ;
-	static const S32 WRITE;
-	static const S32 READ_WRITE;
-	static const S32 APPEND;
-	
-protected:
-	LLAssetType::EType mFileType;
-    BOOL    mReadComplete;
-	LLUUID	mFileID;
-	S32		mPosition;
-	S32		mMode;
-	S32		mBytesRead;
+    public:
+        static const S32 READ;
+        static const S32 WRITE;
+        static const S32 READ_WRITE;
+        static const S32 APPEND;
 
-private:
-    static const std::string idToFilepath(const std::string id, LLAssetType::EType at);
-    static std::string mCacheDirName;
-    static LLDiskCache* mDiskCache;
+    protected:
+        LLAssetType::EType mFileType;
+        LLUUID  mFileID;
+        S32     mPosition;
+        S32     mMode;
+        S32     mBytesRead;
+//private:
+//    static const std::string idToFilepath(const std::string id, LLAssetType::EType at);
 };
 
 #endif  // LL_FILESYSTEM_H
diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index 0123bc32af..2e65aef9a2 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -1351,10 +1351,10 @@
       <key>Value</key>
       <integer>23</integer>
     </map>
-    <key>CacheDebugInfo</key>
+    <key>EnableCacheDebugInfo</key>
     <map>
       <key>Comment</key>
-      <string>When enabled, display additional cache debugging information</string>
+      <string>When set, display additional cache debugging information</string>
       <key>Persist</key>
       <integer>1</integer>
       <key>Type</key>
@@ -1362,6 +1362,28 @@
       <key>Value</key>
       <integer>0</integer>
     </map>
+    <key>DiskCacheMaxSizeMB</key>
+    <map>
+      <key>Comment</key>
+      <string>The maximum number of MB to use for the new disk cache</string>
+      <key>Persist</key>
+      <integer>1</integer>
+      <key>Type</key>
+      <string>U32</string>
+      <key>Value</key>
+      <integer>10</integer>
+    </map>
+    <key>DiskCacheDirName</key>
+    <map>
+      <key>Comment</key>
+      <string>The name of the disk cache (within the standard Viewer disk cache directory)</string>
+      <key>Persist</key>
+      <integer>1</integer>
+      <key>Type</key>
+      <string>String</string>
+      <key>Value</key>
+      <string>dcache</string>
+    </map>
     <key>CacheLocation</key>
     <map>
       <key>Comment</key>
diff --git a/indra/newview/llappviewer.cpp b/indra/newview/llappviewer.cpp
index 0d25cb6dc8..1914ca89de 100644
--- a/indra/newview/llappviewer.cpp
+++ b/indra/newview/llappviewer.cpp
@@ -98,6 +98,7 @@
 #include "lllogininstance.h"
 #include "llprogressview.h"
 #include "llvocache.h"
+#include "lldiskcache.h"
 #include "llvopartgroup.h"
 #include "llweb.h"
 #include "llfloatertexturefetchdebugger.h"
@@ -115,7 +116,6 @@
 #include "llprimitive.h"
 #include "llurlaction.h"
 #include "llurlentry.h"
-#include "llfilesystem.h"
 #include "llvolumemgr.h"
 #include "llxfermanager.h"
 #include "llphysicsextensions.h"
@@ -1855,9 +1855,6 @@ bool LLAppViewer::cleanup()
 	SUBSYSTEM_CLEANUP(LLWorldMapView);
 	SUBSYSTEM_CLEANUP(LLFolderViewItem);
 
-	LL_INFOS() << "Cleaning up disk cache" << LL_ENDL;
-	SUBSYSTEM_CLEANUP(LLFileSystem);
-
 	LL_INFOS() << "Saving Data" << LL_ENDL;
 
 	// Store the time of our current logoff
@@ -4111,6 +4108,9 @@ bool LLAppViewer::initCache()
 	{
 		LLSplashScreen::update(LLTrans::getString("StartupClearingCache"));
 		purgeCache();
+
+        // purge the new C++ file system based cache
+        LLDiskCache::getInstance()->purge();
 	}
 
 	LLSplashScreen::update(LLTrans::getString("StartupInitializingTextureCache"));
@@ -4131,7 +4131,12 @@ bool LLAppViewer::initCache()
 
 	LLVOCache::getInstance()->initCache(LL_PATH_CACHE, gSavedSettings.getU32("CacheNumberOfRegionsForObjects"), getObjectCacheVersion());
 
-	LLFileSystem::initClass();
+    // initialize the new disk cache using saved settings
+    const std::string cache_dir_name = gSavedSettings.getString("DiskCacheDirName");
+    const unsigned int cache_max_bytes = gSavedSettings.getU32("DiskCacheMaxSizeMB") * 1024 * 1024;
+    const bool enable_cache_debug_info = gSavedSettings.getBOOL("EnableDiskCacheDebugInfo");
+    const std::string cache_dir = gDirUtilp->getExpandedFilename(LL_PATH_CACHE, cache_dir_name);
+    LLDiskCache::initParamSingleton(cache_dir, cache_max_bytes, enable_cache_debug_info);
 
     return true;
 }