cocos lua解压zip文件(支持源文件非zip格式)

谁践踏了优雅 2021-12-17 10:53 617阅读 0赞

最近遇到需要在cocos中解压zip的需求就了解了下

以下代码摘自: http://www.cocoachina.com/bbs/read.php?tid=212537

// Open the zip file
        std::string outFileName = filename;
        unzFile zipfile = unzOpen(outFileName.c_str());
        if (!zipfile){
            CCLOG("can not open downloaded zip file %s", outFileName.c_str());
            return false;
        }
     
        // Get info about the zip file
        unz_global_info global_info;
        if (unzGetGlobalInfo(zipfile, &global_info) != UNZ_OK){
            CCLOG("can not read file global info of %s", outFileName.c_str());
            unzClose(zipfile);
            return false;
        }
     
        const int BUFFER_SIZE = 8192;
        const int MAX_FILENAME = 512;
    
        // Buffer to hold data read from the zip file
        char readBuffer[BUFFER_SIZE];
     
        // Loop to extract all files.
        uLong i;
        for (i = 0; i < global_info.number_entry; ++i){
            // Get info about current file.
            unz_file_info fileInfo;
            char fileName[MAX_FILENAME];
            if (unzGetCurrentFileInfo(zipfile, &fileInfo, fileName, MAX_FILENAME, NULL, 0, NULL, 0) != UNZ_OK){
                CCLOG("can not read file info");
                unzClose(zipfile);
                return false;
            }
     
            std::string storagePath = destPath;
            std::string fullPath = storagePath + fileName;
     
            // Check if this entry is a directory or a file.
            const size_t filenameLength = strlen(fileName);
            if (fileName[filenameLength - 1] == '/'){
                // get all dir
                std::string fileNameStr = std::string(fileName);
                size_t position = 0;
                while ((position = fileNameStr.find_first_of("/", position)) != std::string::npos){
                    std::string dirPath = storagePath + fileNameStr.substr(0, position);
                    // Entry is a direcotry, so create it.
                    // If the directory exists, it will failed scilently.
                    if (!createDirectory(dirPath.c_str())){
                        CCLOG("can not create directory %s", dirPath.c_str());
                        //unzClose(zipfile);
                        //return false;
                    }
                    position++;
                }
            } else {
                // Entry is a file, so extract it.
                // Open current file.
                if (unzOpenCurrentFile(zipfile) != UNZ_OK) {
                    CCLOG("can not open file %s", fileName);
                    unzClose(zipfile);
                    return false;
                }
     
                // Create a file to store current file.
                FILE *out = fopen(fullPath.c_str(), "wb");
                if (!out) {
                    CCLOG("can not open destination file %s", fullPath.c_str());
                    unzCloseCurrentFile(zipfile);
                    unzClose(zipfile);
                    return false;
                }
     
                // Write current file content to destinate file.
                int error = UNZ_OK;
                do {
                    error = unzReadCurrentFile(zipfile, readBuffer, BUFFER_SIZE);
                    if (error < 0) {
                        CCLOG("can not read zip file %s, error code is %d", fileName, error);
                        unzCloseCurrentFile(zipfile);
                        unzClose(zipfile);
                        return false;
                    }
     
                    if (error > 0) {
                        fwrite(readBuffer, error, 1, out);
                    }
                } while (error > 0);
                fclose(out);
            }
     
            unzCloseCurrentFile(zipfile);
     
            // Goto next entry listed in the zip file.
            if ((i + 1) < global_info.number_entry) {
                if (unzGoToNextFile(zipfile) != UNZ_OK) {
                    CCLOG("can not read next file");
                    unzClose(zipfile);
                    return false;
                }
            }
        }

使用zlib 的上层封装 **minizip** 的接口，但是 在ios上会出现非zip后缀的文件，无法读取的尴尬，主要问题出在unzOpen方法。

看了下 可以使用unzOpenBuffer方法就能避免掉这个问题。就变成了:

std::string outFileName = filename;    
        ssize_t size = 0;
        unsigned char *zipFileData = FileUtils::getInstance()->getFileData(outFileName, "rb", &size);　　  
        unzFile zipfile = unzOpenBuffer(zipFileData, size);
        ......

或者直接用cocos封装好的 ZipFile ，也就是:

ZipFile *zip = nullptr;
        if (zipFileData) {
            zip = ZipFile::createWithBuffer(zipFileData, size);
        }

这样就ok。同时了解了下zip格式：

![1372457-20180429164441830-1186479824.png][]

<table> 
 <thead> 
  <tr> 
   <th>Offset</th> 
   <th>Bytes</th> 
   <th>Contents</th> 
   <th>Descriptor</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td><span style="color:#0000FF;">LOCAL FILE HEADER</span></td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
  </tr> 
  <tr> 
   <td>00000000</td> 
   <td>4</td> 
   <td>50 4B 03 04</td> 
   <td>文件头标识(0x04034b50)</td> 
  </tr> 
  <tr> 
   <td>00000004</td> 
   <td>2</td> 
   <td>0A 00</td> 
   <td>解压文件所需 pkware最低版本</td> 
  </tr> 
  <tr> 
   <td>00000006</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>通用比特标志位</td> 
  </tr> 
  <tr> 
   <td>00000008</td> 
   <td>2</td> 
   <td>08 00</td> 
   <td>压缩方式</td> 
  </tr> 
  <tr> 
   <td>0000000A</td> 
   <td>2</td> 
   <td>E1 5D</td> 
   <td>文件最后修改时间</td> 
  </tr> 
  <tr> 
   <td>0000000C</td> 
   <td>2</td> 
   <td>CC 48</td> 
   <td>文件最后修改日期</td> 
  </tr> 
  <tr> 
   <td>0000000E</td> 
   <td>4</td> 
   <td>61 D3 72 09</td> 
   <td>crc-32校验码</td> 
  </tr> 
  <tr> 
   <td>00000012</td> 
   <td>4</td> 
   <td>08 00 00 00</td> 
   <td>压缩后的大小</td> 
  </tr> 
  <tr> 
   <td>00000016</td> 
   <td>4</td> 
   <td>06 00 00 00</td> 
   <td>未压缩的大小</td> 
  </tr> 
  <tr> 
   <td>0000001A</td> 
   <td>2</td> 
   <td>07 00</td> 
   <td>文件名长度</td> 
  </tr> 
  <tr> 
   <td>0000001C</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>扩展区长度</td> 
  </tr> 
  <tr> 
   <td>0000001E</td> 
   <td>6</td> 
   <td>31 32 33 2E 74 78 74</td> 
   <td>文件名 123.txt</td> 
  </tr> 
  <tr> 
   <td><span style="color:#0000FF;">FILE DATA</span></td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
  </tr> 
  <tr> 
   <td>00000025</td> 
   <td>8</td> 
   <td>33 34 32 36 31 35 03 00</td> 
   <td>压缩文件数据，此处就是压缩文本文件123.txt压缩后的数据</td> 
  </tr> 
  <tr> 
   <td><span style="color:#0000FF;">Central Directory Header</span></td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
  </tr> 
  <tr> 
   <td>0000002D</td> 
   <td>4</td> 
   <td>50 4B 01 02</td> 
   <td>核心目录文件header标识=（0x02014b50）</td> 
  </tr> 
  <tr> 
   <td>00000031</td> 
   <td>2</td> 
   <td>0A 00</td> 
   <td>压缩所用的pkware版本</td> 
  </tr> 
  <tr> 
   <td>00000033</td> 
   <td>2</td> 
   <td>0A 00</td> 
   <td>解压所需pkware的最低版本</td> 
  </tr> 
  <tr> 
   <td>00000035</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>通用位标记</td> 
  </tr> 
  <tr> 
   <td>00000037</td> 
   <td>2</td> 
   <td>08 00</td> 
   <td>压缩方法</td> 
  </tr> 
  <tr> 
   <td>00000039</td> 
   <td>2</td> 
   <td>E1 5D</td> 
   <td>文件最后修改时间</td> 
  </tr> 
  <tr> 
   <td>0000003B</td> 
   <td>2</td> 
   <td>CC 48</td> 
   <td>文件最后修改日期</td> 
  </tr> 
  <tr> 
   <td>0000003D</td> 
   <td>4</td> 
   <td>61 D3 72 09</td> 
   <td>CRC-32校验码</td> 
  </tr> 
  <tr> 
   <td>00000041</td> 
   <td>4</td> 
   <td>08 00 00 00</td> 
   <td>压缩后的大小</td> 
  </tr> 
  <tr> 
   <td>00000045</td> 
   <td>4</td> 
   <td>06 00 00 00</td> 
   <td>未压缩的大小</td> 
  </tr> 
  <tr> 
   <td>00000049</td> 
   <td>2</td> 
   <td>07 00</td> 
   <td>文件名长度</td> 
  </tr> 
  <tr> 
   <td>0000004B</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>扩展域长度</td> 
  </tr> 
  <tr> 
   <td>0000004D</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>文件注释长度</td> 
  </tr> 
  <tr> 
   <td>0000004F</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>文件开始位置的磁盘编号</td> 
  </tr> 
  <tr> 
   <td>00000051</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>内部文件属性</td> 
  </tr> 
  <tr> 
   <td>00000053</td> 
   <td>4</td> 
   <td>20 00 00 00</td> 
   <td>外部文件属性</td> 
  </tr> 
  <tr> 
   <td>00000057</td> 
   <td>4</td> 
   <td>00 00 00 00</td> 
   <td>本地文件header的相对位移</td> 
  </tr> 
  <tr> 
   <td>0000005B</td> 
   <td>7</td> 
   <td>31 32 33 2E 74 78 74</td> 
   <td>目录文件名</td> 
  </tr> 
  <tr> 
   <td><span style="color:#0000FF;">End of central directory record</span></td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
   <td>&nbsp;</td> 
  </tr> 
  <tr> 
   <td>00000062</td> 
   <td>4</td> 
   <td>50 4B 05 06</td> 
   <td>核心目录结束标记（0x06054b50）</td> 
  </tr> 
  <tr> 
   <td>00000066</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>当前磁盘编号</td> 
  </tr> 
  <tr> 
   <td>00000068</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>核心目录开始位置的磁盘编号</td> 
  </tr> 
  <tr> 
   <td>0000006A</td> 
   <td>2</td> 
   <td>01 00</td> 
   <td>该磁盘上所记录的核心目录数量</td> 
  </tr> 
  <tr> 
   <td>0000006C</td> 
   <td>2</td> 
   <td>01 00</td> 
   <td>核心目录结构总数</td> 
  </tr> 
  <tr> 
   <td>0000006E</td> 
   <td>4</td> 
   <td>35 00 00 00</td> 
   <td>核心目录的大小</td> 
  </tr> 
  <tr> 
   <td>00000072</td> 
   <td>4</td> 
   <td>2D 00 00 00</td> 
   <td>核心目录开始位置相对于archive开始的位移</td> 
  </tr> 
  <tr> 
   <td>00000076</td> 
   <td>2</td> 
   <td>00 00</td> 
   <td>注释长度</td> 
  </tr> 
 </tbody> 
</table>

https://www.cnblogs.com/menlsh/

https://blog.csdn.net/a200710716/article/details/51644421

转载于:https://www.cnblogs.com/lesten/p/8922706.html

[1372457-20180429164441830-1186479824.png]: /images/20211217/5c1d1873630049c696ace43a2d73d2a3.png