c++ zlib 解压gzip字符串，只解压了678字节

您好，可能是由于您的代码实现不正确导致了解压缩失败。下面是一份简单的C++代码，可以用于解压gzip字符串：

#include <iostream>
#include <fstream>
#include <sstream>
#include <zlib.h>

int main() {
    std::string gzip_str = "H4sIAAAAAAAAAG2QzUrDIBBE93yXURiQqEYDctbT+4QzVJWQC0bga8WjQgW4i6Dy+QY8T8F2gSW\n"
                           "2Gz4jh8e7kM4vN8J5pV1Vms3S8eBpK7ZGnJwEJ2g2r6JqKJ4rEYlMwz7pC5ZwOuTc2fK6z5lO6L\n"
                           "v2j5yqQ1X9H1eOnqvmJi8jf0HmMhNq8rKqJv5OvBePQIy6aJp6W4yBWBv+O8F6v8Ov8pXf+7vOv\n"
                           "w+k1guf2QzUu8wzVW+4sV5a9kzgWZ7t1gAAAA==";
    std::stringstream compressed_ss(gzip_str);
    std::stringstream uncompressed_ss;
    std::string uncompressed_str;

    const int BUFFER_SIZE = 1024;
    char buffer[BUFFER_SIZE];

    z_stream deflate_stream;
    deflate_stream.zalloc = Z_NULL;
    deflate_stream.zfree = Z_NULL;
    deflate_stream.opaque = Z_NULL;
    deflate_stream.avail_in = 0;
    deflate_stream.next_in = Z_NULL;
    inflateInit2(&deflate_stream, 47);

    while (true) {
        deflate_stream.avail_in = compressed_ss.readsome(buffer, BUFFER_SIZE);
        if (deflate_stream.avail_in == 0) {
            break;
        }
        deflate_stream.next_in = (Bytef *) buffer;

        int ret;
        do {
            deflate_stream.avail_out = BUFFER_SIZE;
            deflate_stream.next_out = (Bytef *) buffer;
            ret = inflate(&deflate_stream, 0);
            if (ret != Z_OK && ret != Z_STREAM_END) {
                std::cerr << "error: " << ret << std::endl;
                inflateEnd(&deflate_stream);
                return 1;
            }
            uncompressed_ss.write(buffer, BUFFER_SIZE - deflate_stream.avail_out);
        } while (deflate_stream.avail_out == 0);
    }

    inflateEnd(&deflate_stream);

    uncompressed_str = uncompressed_ss.str();
    std::cout << uncompressed_str << std::endl;

    return 0;
}

您可以将 `gzip_str` 替换为您的gzip字符串，然后运行该程序进行解压缩。如果您的gzip字符串确实只有678字节，那么解压缩后的数据应该也只有678字节。