LaTeX 写作的两个辅助工具：统计中文字数和关闭Acrobat中的PDF文档

LaTeX 没有像 Word 那样自带中文字数统计功能，加上 LaTeX 源文件中有许多控制字符，不能通过文件大小获知其中有多少汉字。为此我用C写了一个统计中文字数的小工具，名为 cwc ，即 chinese word counter。这个程序只有 count_files() 函数使用了 Windows API，稍作修改就能移植到 Linux/Unix 下。


#include <stdio.h>
#include <wchar.h>
#include <windows.h>
int total = 0; // total chinese characters

// UNICODE version word counter
void word_count_u(FILE* pf)
{
    int w = 0, b = 2;
    wint_t c;

    while((c = getwc(pf)) != WEOF) {
        b += 2;         // byte count
        if (c > 127) {  // 中文字符
            w++;        // char count
        }
    }
   
    printf("%10d /t %10d/n", w, b);
    total += w;
}

// word counter
void word_count(const char* file)
{
    int w = 0, b = 0;
    int c;
    int unicode = 0;
   
    FILE *pf = fopen(file, "rb");
    if (NULL == pf) {
        return;
    }
    printf ("%20s : ", file);
    
    // 判断是否为 UNICODE 文件
    if ((c = getc(pf)) == 0xff) {
        int cc;
        if ((cc = getc(pf)) == 0xfe) {
            unicode = 1;
            printf("UNICODE");
            word_count_u(pf);
        }
        else {
            fseek(pf, 0, SEEK_SET);
        }
    }
    else {
        ungetc(c, pf);
    }
   
    if (!unicode) {
        printf("       ");
        while((c = getc(pf)) != EOF) {
            b++; // byte count
            if (c > 127) { // 中文字符
                w++; // char count
                b++; // 每个中文字符占两字节
                if ((c = getc(pf)) == EOF)
                    break;
            }
        }
   
        printf("%10d /t %10d/n", w, b);
        total += w;
    }
    fclose(pf);
}

void count_files(const char* file)
{
    WIN32_FIND_DATA FindFileData;
    HANDLE hFind = FindFirstFile(file, &FindFileData);

    if (INVALID_HANDLE_VALUE == hFind) {
        fprintf(stderr, "Can't find %s/n", file);
        return ;
    }

    do {
        if (FindFileData.dwFileAttributes & FILE_ATTRIBUTE_SYSTEM) {
            continue;
        }
        if (FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
            // do nothing
        }
        else {
            word_count(FindFileData.cFileName);
        }
    } while (FindNextFile(hFind, &FindFileData));

    FindClose(hFind);
}

int main(int argc, char* argv[])
{
    if (1 == argc) {
        // default: count all .tex and .txt files in current dir
        count_files("*.tex");
        count_files("*.txt");
    }
    else {
        // get filenames from command line arguments
        while (--argc > 0) {
            count_files(argv[argc]);
        }
    }
    printf("  Total : %d", total);
    return 0;
}

另外一个常见的问题是，用 dvipdfm 生成 PDF 文件时，经常忘了在 Acrobat 中关闭这个文件，而导致出现以下错误提示：

E:/Projects/SlideWindowReport>dvipdfm SlideWindow

SlideWindow.dvi -> SlideWindow.pdf

Unable to open SlideWindow.pdf

Output file removed.

为此我写了一个专门用来关闭 Acrobat 中的 PDF 文件的小工具，名为 closepdf，原理是通过 DDE 告诉 Acrobat 关闭某个 PDF 文件。这个小工具的灵感来自 WinEdt 的自动关闭功能（我跟踪它的宏代码得知如何用 DDE 控制 Acrobat），代码改自 MSDN 的一篇文章。我完全不懂 DDE，不过这不妨碍程序的正常工作:)

有了这个小工具，我就可以写一个 batch file 来编译生成并阅读 PDF 文件：

rem this is m.bat
latex %1
latex %1
closepdf %1.pdf
dvipdfm %1 %2 %3 %4 %5
start %1.pdf

代码如下：
// close the user specified pdf file in Acrobat Reader

// ref. Microsoft Knowledge Base Article - 279721
// HOWTO: Use Dynamic Data Exchange (DDE) with Word and Excel from Visual C++

// modified by Solstice 2004/01/2

#define WIN32_LEAN_AND_MEAN  // Exclude rarely-used stuff from Windows headers
#define STRICT

#include <windows.h>
#include <ddeml.h>
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>

HDDEDATA CALLBACK DdeCallback(
    UINT uType,     // Transaction type.
    UINT uFmt,      // Clipboard data format.
    HCONV hconv,    // Handle to the conversation.
    HSZ hsz1,       // Handle to a string.
    HSZ hsz2,       // Handle to a string.
    HDDEDATA hdata, // Handle to a global memory object.
    DWORD dwData1,  // Transaction-specific data.
    DWORD dwData2)  // Transaction-specific data.
{
    return 0;
}

void DDEExecute(DWORD idInst, HCONV hConv, char* szCommand)
{
    HDDEDATA hData = DdeCreateDataHandle(idInst, (LPBYTE)szCommand,
                               lstrlen(szCommand)+1, 0, NULL, CF_TEXT, 0);
    if (hData==NULL)   {
        printf("Command failed: %s/n", szCommand);
    }
    else    {
        DdeClientTransaction((LPBYTE)hData, 0xFFFFFFFF, hConv, 0L, 0,
                             XTYP_EXECUTE, TIMEOUT_ASYNC, NULL);
    }
}

void DDERequest(DWORD idInst, HCONV hConv, char* szItem, char* sDesc)
{
    HSZ hszItem = DdeCreateStringHandle(idInst, szItem, 0);
    HDDEDATA hData = DdeClientTransaction(NULL,0,hConv,hszItem,CF_TEXT,
                                 XTYP_REQUEST,5000 , NULL);
    if (hData == NULL)
    {
        printf("Request failed: %s/n", szItem);
    }
    else
    {
        char szResult[255];
        DdeGetData(hData, (unsigned char *)szResult, 255, 0);
        printf("%s%s/n", sDesc, szResult);
    }
}

void DDEPoke(DWORD idInst, HCONV hConv, char* szItem, char* szData)
{
    HSZ hszItem = DdeCreateStringHandle(idInst, szItem, 0);
 DdeClientTransaction((LPBYTE)szData, (DWORD)(lstrlen(szData)+1),
                          hConv, hszItem, CF_TEXT,
                          XTYP_POKE, 3000, NULL);
    DdeFreeStringHandle(idInst, hszItem);
}

int get_error(const char* filename)
{
 HANDLE hFile = CreateFile(filename,
     GENERIC_WRITE,
     FILE_SHARE_READ,
     NULL,
     OPEN_EXISTING,
     FILE_ATTRIBUTE_NORMAL,
     NULL);
   
    if (INVALID_HANDLE_VALUE == hFile) {
         return GetLastError();
    } else {
     CloseHandle(hFile);
     return 0;
    }
}

bool is_file_locked(const char* filename)
{   
 return (get_error(filename) == 32);
}

bool is_file_exists(const char* filename)
{
 return (get_error(filename) != 2);
}

int main(int argc, char* argv[])
{
    char szApp[] = "acroview";
    char szTopic[] = "control";
    char szCloseAll[] = "[CloseAllDocs()]";
    char full_file_name[MAX_PATH];
 const char* file_to_close = argv[1];
   
    if (argc == 1) {
     // close all pdf files
 } else { // close the specified file
  if (!is_file_exists(file_to_close)) {
   printf("%s doesn't exists./n", file_to_close);
   return 1;
  }
  if (is_file_locked(file_to_close)) {
   printf("%s is open, trying to close it.../n", file_to_close);
  } else {
   printf("%s is closed./n", file_to_close);
   return 0;
  }
  assert (GetFullPathName(
      file_to_close,
      sizeof(full_file_name),
      full_file_name,
      NULL
  ) > 0);
  //printf("Full name : /"%s/"/n", full_file_name);
 }
   
    //[DocOpen(""%P/%N.pdf"")]
    //[DocClose(""%P/%N.pdf"")]

    //DDE Initialization
    DWORD idInst=0;
    UINT iReturn;
    iReturn = DdeInitialize(&idInst, (PFNCALLBACK)DdeCallback,
                            APPCLASS_STANDARD | APPCMD_CLIENTONLY, 0 );
    if (iReturn!=DMLERR_NO_ERROR)
    {
        printf("DDE Initialization Failed: 0x%04x/n", iReturn);
        Sleep(1500);
        return 0;
    }

    //DDE Connect to Server using given AppName and topic.
    HSZ hszApp, hszTopic;
    HCONV hConv;
    hszApp = DdeCreateStringHandle(idInst, szApp, 0);
    hszTopic = DdeCreateStringHandle(idInst, szTopic, 0);
    hConv = DdeConnect(idInst, hszApp, hszTopic, NULL);
    DdeFreeStringHandle(idInst, hszApp);
    DdeFreeStringHandle(idInst, hszTopic);
    if (hConv == NULL)
    {
        printf("DDE Connection Failed./n");
        Sleep(500); DdeUninitialize(idInst);
        return 0;
    }
    else
    {
     printf("DDE Connection to Acrobat Reader succeed./n");
     Sleep(50);
    }
   
    if (argc == 1) {
     // close all pdf files
     //Execute commands/requests specific to the DDE Server.
     DDEExecute(idInst, hConv, szCloseAll);
     printf("Closing all PDF documents.../n");
     Sleep(50);    
 } else { // close the specified file
  char cmd_buf[MAX_PATH + 100];
     //[DocOpen(""%P/%N.pdf"")]
     //[DocClose(""%P/%N.pdf"")]  
     printf("Closing %s /n", full_file_name);
     snprintf(cmd_buf, sizeof(cmd_buf), "[DocOpen(/"%s/")]", full_file_name);
     DDEExecute(idInst, hConv, cmd_buf);
     Sleep(50);
     snprintf(cmd_buf, sizeof(cmd_buf), "[DocClose(/"%s/")]", full_file_name);
     DDEExecute(idInst, hConv, cmd_buf);
     Sleep(50);
 }

    //DDE Disconnect and Uninitialize.
    DdeDisconnect(hConv);
    DdeUninitialize(idInst);
   
    if (argc == 1) {
     // close all pdf files
     return (0);
    }

    for (int i = 0; i < 5; ++i) {
     Sleep(100);
     if (!is_file_locked(file_to_close))
      break;
    }
    if (!is_file_locked(file_to_close)) {
     printf("%s is closed./n", file_to_close);
     return 0;
    } else {
     printf("%s is still open./n", file_to_close);
     return 1;
    }
}