我正在尝试解析一个git包，我收到了一个POST到https://github.com/codecrafters-io/git-sample-3/git-upload-pack的数据，并将返回的字符串存储在std::string pack中。

pack = pack.substr(20, pack.length() - 40); // skip 8 byte http header, 12 byte pack header, 20 byte pack trailer
    int type;
    int pos = 0;
    std::string lengthstr;
    int length = 0;
    type = (pack[pos] & 112) >> 4; // 112 is 11100000 so this gets the first 3 bits
    length = length | (pack[pos] & 0x0F); // take the last 4 bits
    if (pack[pos] & 0x80) { // if the type bit starts with 0 then the last 4 bits are simply the length
        pos++;
        while (pack[pos] & 0x80) { // while leftmost bit is 1
            length = length << 7;
            length = length | (pack[pos] & 0x7F); // flip first bit to 0 si it's ignored, then we append the other 7 bits to the integer
            pos++;
        }
        length = length << 7;
        length = length | pack[pos]; // set the leftmost bit to 1 so it's ignored, and do the same thing
    }
    pos++;
    FILE* customStdout = fdopen(1, "w");
    FILE* source = fmemopen((void*)pack.substr(pos, length).c_str(), length, "r");
    std::cout << inf(source, customStdout) << "\n";

字符串
其中，inf来自zpipe.c。inf调用的结果是Z_DATA_ERROR，并带有消息incorrect header check
我实际上打印出了二进制的位，从pos开始的位是我期望的zlib头（78 9C），所以我不知道为什么我在这里得到了不正确的头。
我还尝试使用inflateInit2(&strm, -MAX_WBITS)并在pos中添加2以完全跳过标头，但它返回相同的错误，并显示消息invalid stored block lengths