多线程DiskBuffer预读

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    #include <Windows.h>
#include <WinBase.h>

#include "ErrCode.h"

#define DefaultBufferCount 0x200    //512
#define SingleBufferSize 0x40000    //256KB

DWORD WINAPI ThreadBuffering(LPVOID lpParamter);

class DiskBuffer
...{
private:
    int size,front,rear,AllOver;
    int FullWait,EmptyWait;
    HANDLE hFullEvent,hEmptyEvent;
    HANDLE hThread;
    //CRITICAL_SECTION csFull,csEmpty;
    struct StrBuf
    ...{
        char * BufPtr;
        unsigned long File_No;
        size_t Buf_Size;
        size_t Buf_InUse;
    } *tBuf;
public:
    FILE *hListFile;
    DiskBuffer(int sz=DefaultBufferCount,size_t sBufferSize=SingleBufferSize)
    ...{
        rear=0;                front=1;
        FullWait=0;            EmptyWait=0;
        AllOver=0;
        size=(sz>0?sz:DefaultBufferCount)+2;
        tBuf=new StrBuf[size];
        memset(tBuf,0,sizeof(StrBuf)*size);
        for (int i=0;i<size;i++)
        ...{
            tBuf[i].BufPtr=(char*)malloc(sBufferSize);
            tBuf[i].Buf_Size=sBufferSize;
        }
        hFullEvent=CreateEvent(NULL,NULL,NULL,NULL);
        hEmptyEvent=CreateEvent(NULL,NULL,NULL,NULL);
        //InitializeCriticalSection(&csEmpty);
        //InitializeCriticalSection(&csFull);
    }

    ~DiskBuffer()
    ...{
        DWORD ExitCode=0;
        GetExitCodeThread(hThread,&ExitCode);
        if (STILL_ACTIVE==ExitCode)    TerminateThread(hThread,NULL);
        for (int i=0;i<size;i++) free(tBuf[i].BufPtr);
        delete [] tBuf;
        CloseHandle(hFullEvent);
        CloseHandle(hEmptyEvent);
        CloseHandle(hThread);
        //DeleteCriticalSection(&csEmpty);
        //DeleteCriticalSection(&csFull);
    }

    int _StartBuffer(char *ListFile)
    ...{
        if (NULL==(hListFile=fopen((char *)ListFile,"rbS")))...{printf("error open listfile! "); return (_Error_FileOpen);}
        hThread=CreateThread(NULL,NULL,ThreadBuffering,this,NULL,NULL);
        if (hThread!=NULL) return NULL;
        else return _Error_CreatThread;
    }

    int _PopData(char ** it,unsigned long *it_Num)
    ...{
        while (_IsEmpty())
        ...{
            if (AllOver) return 0;
            EmptyWait=1;
                #ifdef _DEBUG
                printf("sta emp wai  %d %d ",front,rear);
                #endif
            WaitForSingleObject(hEmptyEvent,INFINITE);
                #ifdef _DEBUG
                printf("end emp wai  %d %d ",front,rear);
                #endif
        }
        EmptyWait=0;
            #ifdef _DEBUG
            printf("sta pop dat %d %d ",front,rear);
            #endif
        *it=tBuf[front].BufPtr;
        *it_Num=tBuf[front].File_No;
        front=(front+1) % size;
            #ifdef _DEBUG
            printf("end pop dat %d %d %d ",front,rear,*it_Num);
            #endif
        if (FullWait)
        ...{
                #ifdef _DEBUG
                printf("act ful wai %d %d ",front,rear);
                #endif
            SetEvent(hFullEvent);
        }
        return 1;        
    }

    int _PopData(char ** it,unsigned long *it_Num,size_t *it_InUse,size_t *it_Size=NULL)
    ...{
        while (_IsEmpty())
        ...{
            if (AllOver) return 0;
            EmptyWait=1;
                #ifdef _DEBUG
                printf("sta emp wai  %d %d ",front,rear);
                #endif
            WaitForSingleObject(hEmptyEvent,INFINITE);
                #ifdef _DEBUG
                printf("end emp wai  %d %d ",front,rear);
                #endif
        }
        EmptyWait=0;
        //EnterCriticalSection(&csFull);
            #ifdef _DEBUG
            printf("sta pop dat %d %d ",front,rear);
            #endif
        *it=tBuf[front].BufPtr;
        *it_Num=tBuf[front].File_No;
        *it_InUse=tBuf[front].Buf_InUse;
        if (it_Size) *it_Size=tBuf[front].Buf_Size;
        front=(front+1) % size;
            #ifdef _DEBUG
            printf("end pop dat %d %d %d ",front,rear,*it_Num);
            #endif
        if (FullWait)
        ...{
                #ifdef _DEBUG
                printf("act ful wai %d %d ",front,rear);
                #endif
            SetEvent(hFullEvent);
            //FullWait=0;
        }
        //LeaveCriticalSection(&csFull);
        return 1;        
    }
    int _PushData(char * it,unsigned long it_Num,const size_t it_InUse,const size_t it_Size)
    ...{
        //EnterCriticalSection(&csEmpty);
            #ifdef _DEBUG
            printf("sta pus dat %d %d ",front,rear);
            #endif
        int prerear=(rear+1) % size;
        tBuf[prerear].BufPtr=it;
        tBuf[prerear].Buf_Size=it_Size;
        tBuf[prerear].File_No=it_Num;
        rear=prerear;
            #ifdef _DEBUG
            printf("end pus dat %d %d %d ",front,rear,it_Num);
            #endif
        if (EmptyWait)
        ...{
                #ifdef _DEBUG
                printf("act emp wai %d %d ",front,rear);
                #endif
            SetEvent(hEmptyEvent);
            //EmptyWait=0;
        }
        //LeaveCriticalSection(&csEmpty);
        return 1;
    }
    int _GetBuffer(char ** it,size_t *it_Size)
    ...{
        while (_IsFull()) 
        ...{
            FullWait=1;
                #ifdef _DEBUG
                printf("sta ful wai %d %d ",front,rear);
                #endif
            WaitForSingleObject(hFullEvent,INFINITE);
                #ifdef _DEBUG
                printf("end ful wai %d %d ",front,rear);
                #endif
        }
        FullWait=0;
            #ifdef _DEBUG
            printf("sta get BufPtr %d %d ",front,rear);
            #endif
        int prerear=(rear+1) % size;
        *it=tBuf[prerear].BufPtr;
        *it_Size=tBuf[prerear].Buf_Size;
            #ifdef _DEBUG
            printf("end get BufPtr %d %d ",front,rear);
            #endif
        return 1;
    }
    //int _GetLength(void){ return (rear+size-front+1) % size;}
    void _Finished(void)...{ AllOver=1;SetEvent(hEmptyEvent);}
private:
    inline int _IsEmpty(void)
    ...{
        //EnterCriticalSection(&csEmpty);
        //int t=(rear+size-front+1) % size == 0?1:0;
        //LeaveCriticalSection(&csEmpty);
        //return t;
        return (rear+size-front+1) % size == 0?1:0;;
    }
    inline int _IsFull(void)
    ...{
        //EnterCriticalSection(&csFull);
        //int t=(rear+2) % size == front?1:0;
        //LeaveCriticalSection(&csFull);
        //return t;
        return (rear+3) % size == front?1:0;
    }
};

DWORD WINAPI ThreadBuffering(LPVOID lpParamter)
...{
    DiskBuffer *m_Buffer=(DiskBuffer *)lpParamter;
    FILE *m_ListFile=m_Buffer->hListFile;

    char BufPtr[512]=...{0};
    int _filenum=1;
    
    while (fgets(BufPtr,512,m_ListFile))
    ...{            
        if ('*'==BufPtr[0])
        ...{    
            _filenum=atoi(BufPtr+1);                                            //识别标志*,读取文件号
            if (_filenum<=0) ...{printf("error file number! ");exit(_Error_FileNumber); }
        }
        else
        ...{
            unsigned long nbufLen=(unsigned long)strlen(BufPtr)-1;
            if (0x0A==BufPtr[nbufLen] || 0x0D==BufPtr[nbufLen]) BufPtr[nbufLen--]=NULL;        // delete char 0x0A 0x0D
            if (0x0A==BufPtr[nbufLen] || 0x0D==BufPtr[nbufLen]) BufPtr[nbufLen]=NULL;        // delete char 0x0A 0x0D
            if (*BufPtr)
            ...{
                HANDLE hTextFile;
                if(NULL==(hTextFile=CreateFile(BufPtr,GENERIC_READ,FILE_SHARE_READ,NULL,OPEN_EXISTING,FILE_FLAG_SEQUENTIAL_SCAN,NULL)))
                ...{
                    printf("Error open %s ",BufPtr);
                    exit(_Error_FileOpen);
                }
                DWORD m_TextFile_Len=GetFileSize(hTextFile,NULL);
                
                char *m_FileText;
                size_t Old_buf_len;
                m_Buffer->_GetBuffer(&m_FileText,&Old_buf_len);
                if (m_TextFile_Len>Old_buf_len)
                ...{
                    m_FileText=(char*)realloc(m_FileText,m_TextFile_Len+1);
                    Old_buf_len=m_TextFile_Len;
                    if (!m_FileText)...{printf("error memory alloc! ");exit(_Error_Malloc);}
                }
                unsigned long n=0;
                DWORD nRead;
                while ((n++<=3) && (NULL==ReadFile(hTextFile,m_FileText,m_TextFile_Len,&nRead,NULL) || nRead!=m_TextFile_Len)) SetFilePointer(hTextFile,NULL,NULL,FILE_BEGIN);
                if (n>3)...{printf("Error read %s ",BufPtr);exit(_Error_FileRead);}
                CloseHandle(hTextFile);    
                m_FileText[m_TextFile_Len]=NULL;
                m_Buffer->_PushData(m_FileText,_filenum++,m_TextFile_Len,Old_buf_len);
            }
        }
    }
    m_Buffer->_Finished();
    return NULL;
}