1. 问题来源：在Windows上编译了一个cgit, 加了source-filter，代码高亮（使用highlight处理）之后，死活不显示代码。发现是execvp的问题，开始想好好弄，后来放弃了，反正只加个代码高亮，直接dirtry的解决方案算了。所以就参照微软的官方<Creating a Child Process with Redirected Input and Output>, 进行highlight进程的创建。测试小文件可以正常高亮，大文件就会卡住。

2.问题所在和解决方案：经过各种查找，定位到了WriteFile给子线程的Stdin pipe时发生了阻塞。查了查，发现CreatePipes时，有buffersize的设置，增大buffersize, 问题得到了解决。

贴出Dirty的核心代码吧：

1.  

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   #define _WIN32_WINNT 0x0600 #define WIN32_LEAN_AND_MEAN #include <windows.h> #include <winnt.h> #include <winternl.h> #include <stdio.h> #include <errno.h> #include <assert.h> #include <process.h>    typedef struct ProcessPrepare_Info {     PROCESS_INFORMATION child_pi;     HANDLE IN_Rd;     HANDLE IN_Wr;     HANDLE OUT_Rd;     HANDLE OUT_Wr;  } PPInfo;    #define BUFSIZE 4096 #define PIPE_BUFSIZE 1024*1024*1024

2.  

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   PPInfo prepare_highlight(const char* filename) {     SECURITY_ATTRIBUTES saAttr;     char file_ext[1024];     char *fext;     PPInfo ppinfo;           PROCESS_INFORMATION child_pi;           HANDLE g_hChildStd_IN_Rd = NULL;     HANDLE g_hChildStd_IN_Wr = NULL;     HANDLE g_hChildStd_OUT_Rd = NULL;     HANDLE g_hChildStd_OUT_Wr = NULL;             fext = get_filename_ext(filename);     if (!fext)         strcpy(file_ext,"txt");     else         strcpy(file_ext,fext);           if (strstr(filename,"Makefile") == filename)         strcpy(file_ext,"mk");             // printf("\n->Start of parent execution.\n");       // Set the bInheritHandle flag so pipe handles are inherited.       saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);     saAttr.bInheritHandle = TRUE;     saAttr.lpSecurityDescriptor = NULL;       // Create a pipe for the child process's STDOUT.       if (!CreatePipe(&g_hChildStd_OUT_Rd, &g_hChildStd_OUT_Wr, &saAttr, PIPE_BUFSIZE))         debug_log(TEXT("StdoutRd CreatePipe"));       // Ensure the read handle to the pipe for STDOUT is not inherited.       if (!SetHandleInformation(g_hChildStd_OUT_Rd, HANDLE_FLAG_INHERIT, 0))         debug_log(TEXT("Stdout SetHandleInformation"));       // Create a pipe for the child process's STDIN.       if (!CreatePipe(&g_hChildStd_IN_Rd, &g_hChildStd_IN_Wr, &saAttr, PIPE_BUFSIZE))         debug_log(TEXT("Stdin CreatePipe"));       // Ensure the write handle to the pipe for STDIN is not inherited.       if (!SetHandleInformation(g_hChildStd_IN_Wr, HANDLE_FLAG_INHERIT, 0))         debug_log(TEXT("Stdin SetHandleInformation"));       // Create the child process.       child_pi = CreateChildProcess(file_ext,g_hChildStd_OUT_Wr,g_hChildStd_IN_Rd);           debug_log("Create highlight process finished.\n");           ppinfo.child_pi = child_pi;     ppinfo.IN_Rd = g_hChildStd_IN_Rd;     ppinfo.IN_Wr = g_hChildStd_IN_Wr;     ppinfo.OUT_Rd = g_hChildStd_OUT_Rd;     ppinfo.OUT_Wr = g_hChildStd_OUT_Wr;           return ppinfo; }

    

3.  

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   void wait_highlight(PPInfo ppinfo) {     //WaitForSingleObject(ppinfo.child_pi.hProcess, INFINITE);     WaitForSingleObject(ppinfo.child_pi.hProcess, 10000);           if (!CloseHandle(ppinfo.OUT_Wr))         debug_log(TEXT("Child StdOutWr CloseHandle"));       // Read from pipe that is the standard output for child process.       //printf("\n->Contents of child process STDOUT:\n\n", argv[1]);     ReadFromPipe(ppinfo.OUT_Rd);       //printf("\n->End of parent execution.\n");       // The remaining open handles are cleaned up when this process terminates.     // To avoid resource leaks in a larger application, close handles explicitly. }

    

4.  

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   DWORD WriteBufToPipe(HANDLE wHandle,const char* buf, DWORD bufsize)   // Read from a file and write its contents to the pipe for the child's STDIN. // Stop when there is no more data. {     int i, dwRead;     DWORD dwWritten;     CHAR chBuf[BUFSIZE+1];     BOOL bSuccess = FALSE;           chBuf[BUFSIZE] = 0; #if false             bSuccess = WriteFile(wHandle, buf, bufsize, &dwWritten, NULL);       #else     i=0;     for (;;)     {         //bSuccess = ReadFile(g_hInputFile, chBuf, BUFSIZE, &dwRead, NULL);         //if (!bSuccess || dwRead == 0) break;         dwRead = (bufsize - BUFSIZE*i);         if ( dwRead <= 0) break;         dwRead = min(dwRead+1,BUFSIZE);         memcpy(chBuf,&(buf[BUFSIZE*i]),dwRead);         debug_log("Write %d bytes of chbuf %s to handle\n",dwRead,chBuf);         bSuccess = WriteFile(wHandle, chBuf, dwRead, &dwWritten, NULL);         debug_log("Write buf %d time,bSuccess=%d\n",i,bSuccess);         if (!bSuccess) break;         FlushFileBuffers(wHandle);         debug_log("Flush write handle.\n");         i=i+1;     } #endif           debug_log("Write buf finished\n");       // Close the pipe handle so the child process stops reading.       if (!CloseHandle(wHandle))         debug_log(TEXT("StdInWr CloseHandle"));           return dwWritten; }

    

5.  

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   PROCESS_INFORMATION CreateChildProcess(const char* file_ext,HANDLE hOutput, HANDLE hInput) // Create a child process that uses the previously created pipes for STDIN and STDOUT. {     TCHAR szCmdline[1024] = TEXT("D:\\Data\\WebRoot\\cgit\\highlight-3.39-x64\\highlight.exe --force --inline-css -f -I -O xhtml -S ");     PROCESS_INFORMATION piProcInfo;     STARTUPINFO siStartInfo;     BOOL bSuccess = FALSE;           //Append file extension     strcat(szCmdline,file_ext);           debug_log("%s\n",szCmdline);       // Set up members of the PROCESS_INFORMATION structure.       ZeroMemory(&piProcInfo, sizeof(PROCESS_INFORMATION));       // Set up members of the STARTUPINFO structure.     // This structure specifies the STDIN and STDOUT handles for redirection.       ZeroMemory(&siStartInfo, sizeof(STARTUPINFO));     siStartInfo.cb = sizeof(STARTUPINFO);     siStartInfo.hStdError = hOutput;//g_hChildStd_OUT_Wr;     siStartInfo.hStdOutput = hOutput;//g_hChildStd_OUT_Wr;     siStartInfo.hStdInput = hInput;//g_hChildStd_IN_Rd;     siStartInfo.dwFlags |= STARTF_USESTDHANDLES;       // Create the child process.       bSuccess = CreateProcess(TEXT("D:\\Data\\WebRoot\\cgit\\highlight-3.39-x64\\highlight.exe"),         szCmdline,     // command line         NULL,          // process security attributes         NULL,          // primary thread security attributes         TRUE,          // handles are inherited         0,             // creation flags         NULL,          // use parent's environment         NULL,          // use parent's current directory         &siStartInfo,  // STARTUPINFO pointer         &piProcInfo);  // receives PROCESS_INFORMATION       // If an error occurs, exit the application.     if (!bSuccess)         debug_log(TEXT("CreateProcess Failed."));     else     {         // Close handles to the child process and its primary thread.         // Some applications might keep these handles to monitor the status         // of the child process, for example.           CloseHandle(piProcInfo.hProcess);         CloseHandle(piProcInfo.hThread);     }     return piProcInfo; }

    

6.  

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   const char *get_filename_ext(const char *filename) {     const char *dot = strrchr(filename, '.');     if(!dot || dot == filename) return NULL;     return dot + 1; }

    

7. Test Main Code

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   int test_process2(const char* filename,const char* buf, DWORD bufsize) {     PPInfo cIn;           int i, dwRead;     DWORD dwWritten;     CHAR chBuf[BUFSIZE+1];     BOOL bSuccess = FALSE;           chBuf[BUFSIZE] = 0;           debug_log("test_process2 start.\n");           cIn=prepare_highlight(filename);           //WriteToPipe(cIn.IN_Wr,g_hInputFile);     i=0;     for (;;)     {         //bSuccess = ReadFile(g_hInputFile, chBuf, BUFSIZE, &dwRead, NULL);         //if (!bSuccess || dwRead == 0) break;         dwRead = (bufsize - BUFSIZE*i);         if ( dwRead <= 0) break;         dwRead = min(dwRead+1,BUFSIZE);         memcpy(chBuf,&(buf[BUFSIZE*i]),dwRead);         debug_log("Write %d bytes of chbuf %s to handle\n",dwRead,chBuf);         bSuccess = WriteFile(cIn.IN_Wr, chBuf, dwRead, &dwWritten, NULL);         debug_log("Write buf %d time\n",i);         if (!bSuccess) break;         i=i+1;     }           debug_log("Write buf finished\n");       // Close the pipe handle so the child process stops reading.       if (!CloseHandle(cIn.IN_Wr))         debug_log(TEXT("StdInWr CloseHandle"));           wait_highlight(cIn);           debug_log("test_process2 finished.\n");           return 0; }

    

PS:

 这里在顺便提一下，如何在Windows下编译cgit, 下载并安装git-sdk，然后在打开的shell里面make即可。之后拷贝到Apache相关目录并设置即可。