C++实现多线程查找文件实例

//线程函数 
UINT FinderEntry(LPVOID lpParam) 
{ 
    //CRapidFinder通过参数传递进来  
    CRapidFinder* pFinder = (CRapidFinder*)lpParam; 
    CDirectoryNode* pNode = NULL; 
    BOOL bActive = TRUE; //bActive为TRUE,表示当前线程激活 
    //循环处理m_listDir列表中的目录 
    while (1) 
    { 
        //从列表中取出一个目录 
        ::EnterCriticalSection(&pFinder->m_cs); 
        if (pFinder->m_listDir.IsEmpty()) //目录列表为空，当前线程不激活，所以bAactive=FALSE 
        { 
            bActive = FALSE; 
        } 
        else 
        { 
            pNode = pFinder->m_listDir.GetHead(); //得到一个目录 
            pFinder->m_listDir.Remove(pNode);    //从目录列表中移除 
        } 
        ::LeaveCriticalSection(&pFinder->m_cs); 
        //如果停止当前线程 
        if (bActive == FALSE) 
        { 
            //停止当前线程 
            //线程数-- 
            pFinder->m_nThreadCount--; 
             
            //如果当前活动线程数为0,跳出，结束 
            if (pFinder->m_nThreadCount == 0) 
            { 
                ::LeaveCriticalSection(&pFinder->m_cs); 
                break; 
            } 
            ::LeaveCriticalSection(&pFinder->m_cs); 
            //当前活动线程数不为0，等待其他线程向目录列表中加目录 
            ::ResetEvent(pFinder->m_hDirEvent); 
            ::WaitForSingleObject(pFinder->m_hDirEvent, INFINITE); 
 
            //运行到这，就说明其他线程唤醒了本线程 
             
            pFinder->m_nThreadCount++; //激活了自己的线程，线程数++ 
             
            bActive = TRUE; //当前线程活了 
            continue; //跳到while, 
        } 
        //从目录列表中成功取得了目录 
<span style="white-space:pre">      </span>...................... 
         
        //if (pNode) 
        //{ 
        //  delete pNode; 
        //  pNode = NULL; 
        //} 
 
 
    }//end while 
 
    //促使一个搜索线程从WaitForSingleObject返回，并退出循环 
    ::SetEvent(pFinder->m_hDirEvent); 
 
    //判断此线程是否是最后一个结束循环的线程，如果是就通知主线程 
    if (::WaitForSingleObject(pFinder->m_hDirEvent,0) != WAIT_TIMEOUT) 
    { 
        ::SetEvent(pFinder->m_hExitEvent); 
    } 
    return 1; 
}

//从目录列表中成功取得了目录 
WIN32_FIND_DATA fileData; 
HANDLE hFindFile; 
//生成正确的查找字符串 
if (pNode->szDir[strlen(pNode->szDir)-1] != '\\') 
{ 
    strcat(pNode->szDir,"\\"); 
} 
strcat(pNode->szDir, "*.*"); 
//查找文件的框架 
hFindFile = ::FindFirstFile(pNode->szDir, &fileData); 
if (hFindFile != INVALID_HANDLE_VALUE ) 
{ 
    do  
    { 
 //如果是当前目录，跳过 
 if (fileData.cFileName[0] == '.') 
 { 
     continue; 
 } 
 //如果是目录 
 if (fileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) 
 { 
     //将当前目录加入到目录列表 
     。。。。。。 
     //使一个线程从非活动状态变成活动状态 
     ::SetEvent(pFinder->m_hDirEvent); 
 } 
 else //如果是文件 
 { 
     。。。。。。。。。。。。。 
 } 
    } while (::FindNextFile(hFindFile, &fileData)); 
}

#include "RapidFinder.h" 
#include <stddef.h> 
#include <stdio.h> 
#include <process.h> 
 
//m_nMaxThread 是const int类型，只能通过这种方式初始化 
CRapidFinder::CRapidFinder(int nMaxThread):m_nMaxThread(nMaxThread) 
{ 
    m_nResultCount = 0; 
    m_nThreadCount = 0; 
    m_listDir.Construct(offsetof(CDirectoryNode, pNext));  //offsetof在stddef.h头文件中 
    ::InitializeCriticalSection(&m_cs); 
    m_szMatchName[0] = '\0'; 
    m_hDirEvent = ::CreateEvent(NULL, FALSE, FALSE, NULL); 
    m_hExitEvent = ::CreateEvent(NULL, FALSE, FALSE, NULL); 
 
} 
 
CRapidFinder::~CRapidFinder() 
{ 
    ::DeleteCriticalSection(&m_cs); 
    ::CloseHandle(m_hDirEvent); 
    ::CloseHandle(m_hExitEvent); 
} 
 
BOOL    CRapidFinder::CheckFile(LPCTSTR lpszFileName) 
{ 
    //定义两个字符串 
    char string[MAX_PATH]; 
    char strSearch[MAX_PATH]; 
    strcpy(string, lpszFileName); 
    strcpy(strSearch, m_szMatchName); 
 
    //将字符串大写 
    _strupr(string); 
    _strupr(strSearch); 
 
    //比较string中是否含有strSearch 
    if (strstr(string, strSearch) != NULL) 
    { 
        return TRUE; 
    } 
    return FALSE; 
}
 
//线程函数 
UINT FinderEntry(LPVOID lpParam) 
{ 
    //CRapidFinder通过参数传递进来  
    CRapidFinder* pFinder = (CRapidFinder*)lpParam; 
    CDirectoryNode* pNode = NULL; 
    BOOL bActive = TRUE; //bActive为TRUE,表示当前线程激活 
    //循环处理m_listDir列表中的目录 
    while (1) 
    { 
        //从列表中取出一个目录 
        ::EnterCriticalSection(&pFinder->m_cs); 
        if (pFinder->m_listDir.IsEmpty()) //目录列表为空，当前线程不激活，所以bAactive=FALSE 
        { 
            bActive = FALSE; 
        } 
        else 
        { 
            pNode = pFinder->m_listDir.GetHead(); //得到一个目录 
            pFinder->m_listDir.Remove(pNode);    //从目录列表中移除 
        } 
        ::LeaveCriticalSection(&pFinder->m_cs); 
        //如果停止当前线程 
        if (bActive == FALSE) 
        { 
            //停止当前线程 
            ::EnterCriticalSection(&pFinder->m_cs); 
            pFinder->m_nThreadCount--; 
             
            //如果当前活动线程数为0,跳出，结束 
            if (pFinder->m_nThreadCount == 0) 
            { 
                ::LeaveCriticalSection(&pFinder->m_cs); 
                break; 
            } 
            ::LeaveCriticalSection(&pFinder->m_cs); 
            //当前活动线程数不为0，等待其他线程向目录列表中加目录 
            ::ResetEvent(pFinder->m_hDirEvent); 
            ::WaitForSingleObject(pFinder->m_hDirEvent, INFINITE); 
 
            //运行到这，就说明其他线程向目录列表中加入了新的目录 
            ::EnterCriticalSection(&pFinder->m_cs); 
            pFinder->m_nThreadCount++; //激活了自己的线程，线程数++ 
            ::LeaveCriticalSection(&pFinder->m_cs); 
            bActive = TRUE; //目录不再为空 
            continue; //跳到while,重新在目录列表中取目录 
        } 
        //从目录列表中成功取得了目录 
        WIN32_FIND_DATA fileData; 
        HANDLE hFindFile; 
        //生成正确的查找字符串 
        if (pNode->szDir[strlen(pNode->szDir)-1] != '\\') 
        { 
            strcat(pNode->szDir,"\\"); 
        } 
        strcat(pNode->szDir, "*.*"); 
        //查找文件的框架 
        hFindFile = ::FindFirstFile(pNode->szDir, &fileData); 
        if (hFindFile != INVALID_HANDLE_VALUE ) 
        { 
            do  
            { 
                //如果是当前目录，跳过 
                if (fileData.cFileName[0] == '.') 
                { 
                    continue; 
                } 
                //如果是目录 
                if (fileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) 
                { 
                    //将当前目录加入到目录列表 
                    CDirectoryNode* p = new CDirectoryNode; 
                    strncpy(p->szDir, pNode->szDir, strlen(pNode->szDir)-3); //将pNode后面的*.*三位去掉 
                    strcat(p->szDir, fileData.cFileName); 
                    ::EnterCriticalSection(&pFinder->m_cs); 
                    pFinder->m_listDir.AddHead(p); 
                    ::LeaveCriticalSection(&pFinder->m_cs); 
 
                    // 现在的p刚加入列表，就要delete，肯定会出错 
                    //delete p; 
                    //p = NULL; 
 
                    //使一个线程从非活动状态变成活动状态 
                    ::SetEvent(pFinder->m_hDirEvent); 
                } 
                else //如果是文件 
                { 
                    //判断是否为要查找的文件  
                    if (pFinder->CheckFile(fileData.cFileName)) //符合查找的文件  
                    { 
                        //打印 
                        ::EnterCriticalSection(&pFinder->m_cs); 
                        pFinder->m_nResultCount++; 
                        ::LeaveCriticalSection(&pFinder->m_cs); 
                        printf("find %d:%s\n", pFinder->m_nResultCount, fileData.cFileName); 
                    } 
                } 
            } while (::FindNextFile(hFindFile, &fileData)); 
        } 
        //if (pNode) 
        //{ 
        //  delete pNode; 
        //  pNode = NULL; 
        //} 
 
 
    }//end while 
 
    //促使一个搜索线程从WaitForSingleObject返回，并退出循环 
    ::SetEvent(pFinder->m_hDirEvent); 
 
    //判断此线程是否是最后一个结束循环的线程，如果是就通知主线程 
    if (::WaitForSingleObject(pFinder->m_hDirEvent,0) != WAIT_TIMEOUT) 
    { 
        ::SetEvent(pFinder->m_hExitEvent); 
    } 
    return 1; 
} 
 
void    main() 
{ 
    printf("start:\n"); 
    CRapidFinder* pFinder = new CRapidFinder(64); 
    CDirectoryNode* pNode = new CDirectoryNode; 
    char szPath[] = "c:\\"; 
    char szFile[] = "config"; 
 
    strcpy(pNode->szDir, szPath); 
    pFinder->m_listDir.AddHead(pNode); 
 
    strcpy(pFinder->m_szMatchName, szFile); 
    pFinder->m_nThreadCount = pFinder->m_nMaxThread; 
    //开始开启多线程 
    for (int i=0;i< pFinder->m_nMaxThread;i++) 
    { 
        ::CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)FinderEntry, pFinder, 0, NULL); 
    } 
 
    //只有m_hExitEvent受信状态，主线程才恢复运行 
    ::WaitForSingleObject(pFinder->m_hExitEvent,INFINITE); 
    printf("共找到%d\n", pFinder->m_nResultCount); 
    //if (pNode != NULL) delete pNode; 
    if (pFinder != NULL) delete pFinder; 
 
    getchar(); 
    return; 
}

#include "_AFXTLS_.H" 
 
struct CDirectoryNode: public CNoTrackObject 
{ 
    CDirectoryNode* pNext; 
    char szDir[MAX_PATH]; 
}; 
 
class CRapidFinder 
{ 
public: 
    CRapidFinder(int nMaxThread); //构造函数 
    virtual ~CRapidFinder();    //析构函数 
    BOOL    CheckFile(LPCTSTR lpszFileName); //检查lpszFileName是否符合查找条件 
    int     m_nResultCount; //找到的结果数量 
    int     m_nThreadCount; //当前的线程数量 
    CTypedSimpleList<CDirectoryNode*> m_listDir; //查找目录 
    CRITICAL_SECTION    m_cs;   //共享 
    const int   m_nMaxThread;   //最大线程数量 
    char    m_szMatchName[MAX_PATH]; //要查找的名称 
    HANDLE  m_hDirEvent;    //添加新目录后置位 
    HANDLE  m_hExitEvent;   //所有线程退出时置位 
};

#include "_AFXTLS_.H" 
 
void CSimpleList::AddHead(void* p) 
{ 
    *GetNextPtr(p) = m_pHead; 
    m_pHead = p; 
} 
 
BOOL CSimpleList::Remove(void* p) 
{ 
    if (p == NULL) 
    { 
        return FALSE; 
    } 
 
    BOOL bResult = FALSE; 
    if (p == m_pHead) 
    { 
        m_pHead = *GetNextPtr(m_pHead); 
        bResult = TRUE; 
    } 
    else 
    { 
        void* pTest = m_pHead; 
        while (pTest != NULL && *GetNextPtr(pTest) != p) 
        { 
            pTest = *GetNextPtr(pTest); 
        } 
        if (pTest != NULL) 
        { 
            *GetNextPtr(pTest) = *GetNextPtr(p); 
            bResult = TRUE; 
        } 
    } 
 
    return bResult; 
} 
 
void* CNoTrackObject::operator new(size_t nSize) 
{ 
    void* p = ::GlobalAlloc(GPTR, nSize); 
    return  p; 
} 
 
void CNoTrackObject::operator delete(void* p) 
{ 
    if (p!=NULL) 
    { 
        ::GlobalFree(p); 
    } 
}

#ifndef _AFXTLS_H_H 
#define _AFXTLS_H_H 
#include <Windows.h> 
 
class CSimpleList 
{ 
public: 
    CSimpleList(int nNextOffset=0); 
    void Construct(int nNextOffset); 
    BOOL IsEmpty() const; 
    void AddHead(void* p); 
    void RemoveAll(); 
    void* GetHead() const; 
    void* GetNext(void* p) const; 
    BOOL Remove(void* p); 
 
    //为实现接口所需要的成员 
    void* m_pHead; 
    int m_nNextOffset; 
    void** GetNextPtr(void* p) const; 
}; 
 
//类的内联函数 
inline CSimpleList::CSimpleList(int nNextOffset) 
{m_pHead = NULL; m_nNextOffset = nNextOffset;} 
 
inline void CSimpleList::Construct(int nNextOffset) 
{m_nNextOffset = nNextOffset;} 
 
inline BOOL CSimpleList::IsEmpty() const     
{return m_pHead==NULL;} 
 
inline void CSimpleList::RemoveAll() 
{m_pHead=NULL;} 
 
inline void* CSimpleList::GetHead() const 
{return m_pHead;} 
 
inline void* CSimpleList::GetNext(void* preElement) const 
{ 
    return *GetNextPtr(preElement); 
} 
 
inline void** CSimpleList::GetNextPtr(void* p) const 
{ 
    return (void**)((BYTE*)p + m_nNextOffset); 
} 
 
class CNoTrackObject 
{ 
public: 
    void* operator new(size_t nSize); 
    void operator delete(void*); 
    virtual ~CNoTrackObject(){}; 
}; 
 
template<class TYPE> 
 
class CTypedSimpleList:public CSimpleList 
{ 
public: 
    CTypedSimpleList(int nNextOffset=0) 
        :CSimpleList(nNextOffset){} 
    void AddHead(TYPE p) 
    { 
        CSimpleList::AddHead((void*)p); 
    } 
 
    TYPE GetHead() 
    { 
        return (TYPE)CSimpleList::GetHead(); 
    } 
 
    TYPE GetNext(TYPE p) 
    { 
        return (TYPE)CSimpleList::GetNext((void*)p); 
    } 
 
    BOOL Remove(TYPE p) 
    { 
        return CSimpleList::Remove(p); 
    } 
 
    operator TYPE() 
    { 
        return (TYPE)CSimpleList::GetHead(); 
    } 
}; 
#endif