source: box/trunk/lib/raidfile/RaidFileUtil.h @ 2506

// --------------------------------------------------------------------------
//
// File
//              Name:    RaidFileUtil.h
//              Purpose: Utilities for the raid file classes
//              Created: 2003/07/11
//
// --------------------------------------------------------------------------

#ifndef RAIDFILEUTIL__H
#define RAIDFILEUTIL__H

#include "RaidFileController.h"
#include "RaidFileException.h"

// note: these are hardcoded into the directory searching code
#define RAIDFILE_EXTENSION                      ".rf"
#define RAIDFILE_WRITE_EXTENSION        ".rfw"

// --------------------------------------------------------------------------
//
// Class
//              Name:    RaidFileUtil
//              Purpose: Utility functions for RaidFile classes
//              Created: 2003/07/11
//
// --------------------------------------------------------------------------
class RaidFileUtil
{
public:
        typedef enum 
        {
                NoFile = 0,
                NonRaid = 1,
                AsRaid = 2,
                AsRaidWithMissingReadable = 3,
                AsRaidWithMissingNotRecoverable = 4
        } ExistType;
        
        enum
        {
                Stripe1Exists = 1,
                Stripe2Exists = 2,
                ParityExists = 4
        };
        
        static ExistType RaidFileExists(RaidFileDiscSet &rDiscSet, const std::string &rFilename, int *pStartDisc = 0, int *pExisitingFiles = 0, int64_t *pRevisionID = 0);
        
        static int64_t DiscUsageInBlocks(int64_t FileSize, const RaidFileDiscSet &rDiscSet);
        
        // --------------------------------------------------------------------------
        //
        // Function
        //              Name:    std::string MakeRaidComponentName(RaidFileDiscSet &, const std::string &, int)
        //              Purpose: Returns the OS filename for a file of part of a disc set
        //              Created: 2003/07/11
        //
        // --------------------------------------------------------------------------   
        static inline std::string MakeRaidComponentName(RaidFileDiscSet &rDiscSet, const std::string &rFilename, int Disc)
        {
                if(Disc < 0 || Disc >= (int)rDiscSet.size())
                {
                        THROW_EXCEPTION(RaidFileException, NoSuchDiscSet)
                }
                std::string r(rDiscSet[Disc]);
                r += DIRECTORY_SEPARATOR_ASCHAR;
                r += rFilename;
                r += RAIDFILE_EXTENSION;
                return r;
        }
        
        // --------------------------------------------------------------------------
        //
        // Function
        //              Name:    std::string MakeWriteFileName(RaidFileDiscSet &, const std::string &)
        //              Purpose: Returns the OS filename for the temporary write file
        //              Created: 2003/07/11
        //
        // --------------------------------------------------------------------------   
        static inline std::string MakeWriteFileName(RaidFileDiscSet &rDiscSet, const std::string &rFilename, int *pOnDiscSet = 0)
        {
                int livesOnSet = rDiscSet.GetSetNumForWriteFiles(rFilename);
                
                // does the caller want to know which set it's on?
                if(pOnDiscSet) *pOnDiscSet = livesOnSet;
                
                // Make the string
                std::string r(rDiscSet[livesOnSet]);
                r += DIRECTORY_SEPARATOR_ASCHAR;
                r += rFilename;
                r += RAIDFILE_WRITE_EXTENSION;
                return r;
        }
};

#endif // RAIDFILEUTIL__H