source: downloads/ogre_src_v1-9-0/OgreMain/include/OgreFileSystemLayer.h

/*
 -----------------------------------------------------------------------------
 This source file is part of OGRE
 (Object-oriented Graphics Rendering Engine)
 For the latest info, see http://www.ogre3d.org/
 
 Copyright (c) 2000-2013 Torus Knot Software Ltd
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 -----------------------------------------------------------------------------
 */
#ifndef __FileSystemLayer_H__
#define __FileSystemLayer_H__

#include "OgrePrerequisites.h"
#include "OgreStringVector.h"

namespace Ogre
{
        /** Provides methods to find out where the Ogre config files are stored
            and where logs and settings files should be written to.
                @remarks
                        In modern multi-user OS, a standard user account will often not
                        have write access to the path where the SampleBrowser is stored.
                        In order to still be able to store graphics settings and log
                        output and for the user to overwrite the default Ogre config files, 
                        this class tries to create a folder inside the user's home directory. 
                        Specialised implementations for each individual platform must
                        subclass this abstract interface.
          */

    /** Implementation for the FileSystemLayer interface. */
        class _OgreExport FileSystemLayer : public FileSystemLayerAlloc
        {
        public:
                /** Creates a concrete platform-dependent implementation of FileSystemLayer.
         @param subdir
         A subdirectory inside the user's path to distinguish between
         different Ogre releases.
                 */
                FileSystemLayer(const Ogre::String& subdir)
                {
                        // determine directories to search for config files
                        getConfigPaths();
                        // prepare write location in user directory
                        prepareUserHome(subdir);
                }
        
                /** Search for the given config file in the user's home path. If it can't
         be found there, the function falls back to the system-wide install
         path for Ogre config files. (Usually the same place where the
         SampleBrowser resides, or a special config path above that path.)
         @param filename
         The config file name (without path)
         @return
         The full path to the config file.
                 */
                const Ogre::String getConfigFilePath(Ogre::String filename) const
                {
            #if OGRE_DEBUG_MODE == 1 && (OGRE_PLATFORM != OGRE_PLATFORM_APPLE && OGRE_PLATFORM != OGRE_PLATFORM_APPLE_IOS)
                            // add OGRE_BUILD_SUFFIX (default: "_d") to config file names
                            Ogre::String::size_type pos = filename.rfind('.');
                            if (pos != Ogre::String::npos)
                                    filename = filename.substr(0, pos) + OGRE_BUILD_SUFFIX + filename.substr(pos);
            #endif

                        // look for the requested file in several locations:
            
                        // 1. in the writable path (so user can provide custom files)
                        Ogre::String path = getWritablePath(filename);
                        if (fileExists(path))
                                return path;
            
                        // 2. in the config file search paths
                        for (size_t i = 0; i < mConfigPaths.size(); ++i)
                        {
                                path = mConfigPaths[i] + filename;
                                if (fileExists(path))
                                        return path;
                        }
            
                        // 3. fallback to current working dir
                        return filename;
                }
        
                /** Find a path where the given filename can be written to. This path 
         will usually be in the user's home directory. This function should
         be used for any output like logs and graphics settings.
         @param filename
         Name of the file.
         @return
         The full path to a writable location for the given filename.
                 */
                const Ogre::String getWritablePath(const Ogre::String& filename) const
                {
                        return mHomePath + filename;
                }
                
                void setConfigPaths(const Ogre::StringVector &paths){
                        mConfigPaths = paths;
                }
                
                void setHomePath(const Ogre::String &path){
                        mHomePath = path;
                }
        
                /** Create a directory */
                bool createDirectory(const Ogre::String& name);
        
        private:
                Ogre::StringVector mConfigPaths;
                Ogre::String mHomePath;
        
                /** Determine config search paths. */
                void getConfigPaths();
        
                /** Create an Ogre directory and the given subdir in the user's home. */
                void prepareUserHome(const Ogre::String& subdir);
        
                /** Test if the given file exists. */
                bool fileExists(const Ogre::String& path) const;
        };

}


#endif