#include?“sysinclude.h“
#include?
#include?
#include?
#include?
#include?
using?namespace?std;

extern?void?SendframePacket（unsigned?char*?pData?unsigned?int?len）;

#define?WINDOW_SIZE_STOP_WAIT???????????1
#define?WINDOW_SIZE_BACK_N_frame????????4


#define?MAX_DATA_SIZE???????????????????100

typedef?enum?{data?ack?nak}?frame_kind;
typedef?struct
{
????frame_kind??kind;???????????????????//?kind?of?frame
????unsigned?int?seq;???????????????????//?seq?no?of?frame
????unsigned?int?ack;???????????????????//?ack?no?of?frame
????unsigned?char?data[MAX_DATA_SIZE];??//?data
}frame_head;

typedef?struct
{
????frame_head?head;????????????????????//?frame?head
????unsigned?int?size;??????????????????//?frame?sizei?actual?size?of?data
}frame;

/*
?*?停等協(xié)議測試函數(shù)
?*?參數(shù)說明：
?***?pBuffer????指針，系統(tǒng)要發(fā)送或者已經(jīng)接收到的幀內(nèi)容，或者指向超時信息中
????????????????的超時幀序號
?***?bufferSize?????pBuffer表示內(nèi)容的長度
?***?messageType????傳入消息的類型，可選項由宏定義
?*?返回值：
?***?0??發(fā)送成功
?***?-1?發(fā)送失敗
?*/
int?stud_slide_window_stop_and_wait（char?*pBuffer?
????????????????????????????????????int?bufferSize?
????????????????????????????????????UINT8?messageType）
{
????/*
?????*?為方便后續(xù)兩個函數(shù)的編程，我們定義兩個隊列：
?????***?waitQueue
?????******?暫時無法發(fā)送的數(shù)據(jù)包（沒有可用窗口），緩存在該隊列中；
?????***?confirmQueue
?????******?已經(jīng)發(fā)送但是尚未確認的數(shù)據(jù)包，緩存在該隊列中；
?????*?注：對于停止等待協(xié)議而言，confirmQueue其實不需要，我們可以使用一個結(jié)構(gòu)體記錄
?????*?尚未確認的數(shù)據(jù)包即可，因為該協(xié)議中，尚未確認的數(shù)據(jù)包數(shù)目永遠不會大于1。
?????*/
????static?queueame>?waitQueue;
????static?vectorame>?confirmQueue;
????static?unsigned?int?expectedNo?=?0;???//?記錄當(dāng)前期望收到的數(shù)據(jù)包?seq?no

????/*
?????*?當(dāng)上層傳來一個新數(shù)據(jù)包?i?時，我們需要進行如下判斷：
?????*?Case1...messageType?==?MSG_TYPE_SEND
?????***?Subcase1...waitQueue?不為空
?????******?我們采用?FIFO?方案，此時僅僅需要將?i?掛載到?waitQueue?隊列尾部，
????????????并且為之標(biāo)記序號；
?????**?Subcase2...waitQueue?為空
?????******?我們需要進一步判斷：
????????????Subsubcase1...confirmQueue?為空
????????????????我們直接發(fā)送當(dāng)前數(shù)據(jù)包
????????????Subsubcase2...comfirmQueue?不為空
????????????????將數(shù)據(jù)包?i?掛載到?waitQueue?隊列，并為之標(biāo)記序號
?????***?Case2...messageType?==?MSG_TYPE_RECEIVE?&&?ACK
?????******?此時檢查?ACK（i）?所響應(yīng)的數(shù)據(jù)包?（i-1）?是否存在于?confirmQueue:
????????????如果存在則直接刪除，并且檢查?waitQueue?中是否存在需要發(fā)送的數(shù)據(jù)包；
????????????如果不存在，直接丟棄當(dāng)前ACK數(shù)據(jù)包
?????***?Case3...messageType?==?MSG_TYPE_TIMEOUT
?????******?如果?confirmQueue?中存在數(shù)據(jù)包，則重新發(fā)送這個數(shù)據(jù)包；
????????????如果不存在，說明程序出現(xiàn)bug;
?????*/
????switch（?messageType?）
????{
????????case?MSG_TYPE_TIMEOUT:
????????{
????????????if?（?confirmQueue.size（）?==?0?）
????????????????return?-1;
????????????assert（confirmQueue.size（）?==?1）;
????????????SendframePacket（（unsigned?char?*）&confirmQueue.front（）
????????????????????????????confirmQueue.front（）.size）;
????????????return?0;
????????}
????????case?MSG_TYPE_SEND:
????????{
????????????frame?sendframe;
????????????memcpy（?（void?*）&sendframe.head
????????????????????（void?*）pBuffer
????????????????????bufferSize?）;
????????????sendframe.size?=?bufferSize;

????????????if?（?waitQueue.empty

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件??????10322??2012-09-06?14:44??labs\lab01.cpp

?????文件???????6621??2012-09-06?14:44??labs\lab02.cpp

?????文件???????6510??2012-09-06?14:44??labs\lab03.cpp

?????文件???????5204??2012-09-06?14:44??labs\lab04.cpp

?????文件???????7137??2012-09-06?14:41??labs\lab05.cpp

?????文件??????13459??2012-09-06?14:44??labs\lab06.cpp

?????文件??????18633??2012-09-06?14:43??labs\lab07.cpp

?????文件??????10256??2012-09-06?14:44??labs\lab08.cpp

?????文件???????6606??2012-06-12?14:35??labs\lab09.cpp

?????目錄??????????0??2012-09-07?18:42??labs

-----------?---------??----------?-----??----

????????????????84748????????????????????10