lllfsthread.h

Go to the documentation of this file.

#ifndef LL_LLLFSTHREAD_H
#define LL_LLLFSTHREAD_H

#include <queue>
#include <string>
#include <map>
#include <set>

#include "llapr.h"

#include "llqueuedthread.h"

//============================================================================
// Threaded Local File System
//============================================================================

class LLLFSThread : public LLQueuedThread
{
        //------------------------------------------------------------------------
public:
        enum operation_t {
                FILE_READ,
                FILE_WRITE,
                FILE_RENAME,
                FILE_REMOVE
        };

        //------------------------------------------------------------------------
public:

        class Responder : public LLThreadSafeRefCount
        {
        protected:
                ~Responder();
        public:
                virtual void completed(S32 bytes) = 0;
        };

        class Request : public QueuedRequest
        {
        protected:
                virtual ~Request(); // use deleteRequest()
                
        public:
                Request(LLLFSThread* thread,
                                handle_t handle, U32 priority, 
                                operation_t op, const LLString& filename,
                                U8* buffer, S32 offset, S32 numbytes,
                                Responder* responder);

                S32 getBytes()
                {
                        return mBytes;
                }
                S32 getBytesRead()
                {
                        return mBytesRead;
                }
                S32 getOperation()
                {
                        return mOperation;
                }
                U8* getBuffer()
                {
                        return mBuffer;
                }
                const LLString& getFilename()
                {
                        return mFileName;
                }
                
                /*virtual*/ bool processRequest();
                /*virtual*/ void finishRequest(bool completed);
                /*virtual*/ void deleteRequest();
                
        private:
                LLLFSThread* mThread;
                operation_t mOperation;
                
                LLString mFileName;
                
                U8* mBuffer;    // dest for reads, source for writes, new UUID for rename
                S32 mOffset;    // offset into file, -1 = append (WRITE only)
                S32 mBytes;             // bytes to read from file, -1 = all
                S32 mBytesRead; // bytes read from file

                LLPointer<Responder> mResponder;
        };

        //------------------------------------------------------------------------
public:
        LLLFSThread(bool threaded = TRUE);
        ~LLLFSThread(); 

        // Return a Request handle
        handle_t read(const LLString& filename, /* Flawfinder: ignore */ 
                                  U8* buffer, S32 offset, S32 numbytes,
                                  Responder* responder, U32 pri=0);
        handle_t write(const LLString& filename,
                                   U8* buffer, S32 offset, S32 numbytes,
                                   Responder* responder, U32 pri=0);
        
        // Misc
        U32 priorityCounter() { return mPriorityCounter-- & PRIORITY_LOWBITS; } // Use to order IO operations
        
        // static initializers
        static void initClass(bool local_is_threaded = TRUE); // Setup sLocal
        static S32 updateClass(U32 ms_elapsed);
        static void cleanupClass();             // Delete sLocal

        
private:
        U32 mPriorityCounter;
        
public:
        static LLLFSThread* sLocal;             // Default local file thread
};

//============================================================================


#endif // LL_LLLFSTHREAD_H

---