提高:: ASIO async_read保证读取所有字节 [英] boost::asio async_read guarantee all bytes are read

问题描述

我有一个从客户端接收一个COM pressed串（COM pressed与zlib的）的服务器，而我是用 async_receive 从的boost :: ASIO 库获得这个字符串，原来不过是没有保证所有字节将被接收，所以我现在有将其更改为 async_read 。我面对的问题是，收到的字节大小是可变的，所以我不知道如何使用 async_read 不知道要接收的字节数。随着 async_receive 我只是有一个的boost ::数组＆LT;焦炭，1024＆GT; ，然而，这是一个缓冲区是不一定完全填充。

I have a server that receives a compressed string (compressed with zlib) from a client, and I was using async_receive from the boost::asio library to receive this string, it turns out however that there is no guarantee that all bytes will be received, so I now have to change it to async_read. The problem I face is that the size of the bytes received is variable, so I am not sure how to use async_read without knowing the number of bytes to be received. With the async_receive I just have a boost::array<char, 1024>, however this is a buffer that is not necessarily filled completely.

我想知道如果任何人都可以提出一个解决方案，我可以使用async_read即使我不知道的字节数提前收到？

I wondered if anyone can suggest a solution where I can use async_read even though I do not know the number of bytes to be received in advance?

void tcp_connection::start(boost::shared_ptr<ResolverQueueHandler> queue_handler)
{
    if (!_queue_handler.get())
        _queue_handler = queue_handler;

    std::fill(buff.begin(), buff.end(), 0);

    //socket_.async_receive(boost::asio::buffer(buff), boost::bind(&tcp_connection::handle_read, shared_from_this(), boost::asio::placeholders::error));
    boost::asio::async_read(socket_, boost::asio::buffer(buff), boost::bind(&tcp_connection::handle_read, shared_from_this(), boost::asio::placeholders::error));
}

BUFF 是的boost ::数组＆LT;焦炭，1024 GT;

推荐答案

您是怎样期待做到这一点使用任何其他方法？

How were you expecting to do this using any other method?

有一些通用的方法在异步发送庄园可变大小的数据：

There are a few general methods to sending data of variable sizes in an async manor:

1. 将消息 - 这意味着你有一个定义预期的消息之后，其中包含指定长度的数据体长度的头


2. 将流 - 这意味着你有一些标记（这是非常广阔）知道什么时候你得到一个完整的数据包的方法


3. 将连接 - 每个数据完整的数据包中，一旦数据是完整而封闭的单一连接发送
。

因此​​，可以将您的数据进行分析，或长度发送等...

So can your data be parsed, or a length sent etc...

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