Lab 0 Writeup
=============

My name: Catfood

My SUNet ID: 998244353

I collaborated with: An orange cat

This lab took me about `2` hours to do.

My secret code from section 2.1 was: `294080`

- Optional: I had unexpected difficulty with: [打字的手速太慢，telnet会超时]

- Optional: I think you could make this lab better by: [describe]

- Optional: I was surprised by: [describe]

- Optional: I'm not sure about: [describe]

实现细节描述
============

2.1.2：
```
➜  sponge git:(lab0-startercode) ✗ telnet cs144.keithw.org http
Trying 104.196.238.229...
Connected to cs144.keithw.org.
Escape character is '^]'.
GET /hello HTTP/1.1
Host: cs144.keithw.org
Connection: close

HTTP/1.1 200 OK
Date: Tue, 14 Feb 2023 14:17:29 GMT
Server: Apache
Last-Modified: Thu, 13 Dec 2018 15:45:29 GMT
ETag: "e-57ce93446cb64"
Accept-Ranges: bytes
Content-Length: 14
Connection: close
Content-Type: text/plain

Hello, CS144!
Connection closed by foreign host.
```

2.1.3:
```
➜  sponge git:(lab0-startercode) ✗ telnet cs144.keithw.org http
Trying 104.196.238.229...
Connected to cs144.keithw.org.
Escape character is '^]'.
GET /lab0/998244353 HTTP/1.1
Host: cs144.keithw.org
Connection: close

HTTP/1.1 200 OK
Date: Tue, 14 Feb 2023 14:18:54 GMT
Server: Apache
X-You-Said-Your-SunetID-Was: 998244353
X-Your-Code-Is: 294080
Content-length: 113
Vary: Accept-Encoding
Connection: close
Content-Type: text/plain

Hello! You told us that your SUNet ID was "998244353". Please see the HTTP headers (above) for your secret code.
Connection closed by foreign host.
```

2.2:

学校的邮件系统比较智障，做不了

2.3:
```
➜  sponge git:(lab0-startercode) ✗ telnet localhost 9090   
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
fuck
lalal
Connection closed by foreign host.

➜  sponge git:(lab0-startercode) ✗ netcat -v -l -p 9090
Listening on 0.0.0.0 9090
Connection received on localhost 33706
fuck
lalal
```

3.4:

他的提示没啥用，但是doxygen里面有个例子，可以直接看那个例子。
地址可以直接放域名，`Address(host, protocol)`这个重载是可以DNS查询的，因此直接用就行，然后TCP socket，`connect->write->loop read`就好了。

4:

Buffer开了一个STL的`deque`，感觉是最适合做这种buffer的容器了，能够前后插入删除、常数级随机访问、动态调整空间，非常棒的性质。数据类型用的是`char`（byte），方便调整。

write接口没啥东西，控制一下不要超出空间就行。
read接口比较智障，需要这样一个组合，但是实际上好像测试的时候都没用到。。。
```cpp
    std::string data_read = peek_output(len);
    pop_output(len);
    return data_read;
```
最智障的是它的`peek_output`和`pop_output`这两个的设计：peek只能读，啥也不能动，因为是个const函数；pop需要再把东西删掉，然后`read`就是他们的组合。需要注意一下，更新`bytes_read`是在pop里面而不是read，因为大概率在上层的实现中，可能需要把直接调用peek和pop而不是read。