tcp服务器组包

// 协议格式
struct Header
{
int  hflag =0xffffffff  ;
int  htype  ;
int plength ;
};
struct Test
{
Header head;
string data;
};

const static int FLAGG = 0xffffffff;
const static int MAX_LEN = 65536;
virtual void onRead(ssize_t nread, char* buf)
{
static char tmp[MAX_LEN];
static int index = 0;
int intLen = sizeof(int);

// 缓存数据不完整，收到新的包头
if (index > 0 && nread > intLen * 3 && memcmp(buf, (void*)&FLAGG, sizeof(FLAGG)) == 0)
{
std::cout << *(int*)(tmp + intLen) << "类型不完整" << std::endl;
memset(tmp, 0, MAX_LEN);
index = 0;
}

for (int i = 0; i < nread && index < MAX_LEN; ++i)
{
if (index == intLen && memcmp(tmp, (void*)&FLAGG, sizeof(FLAGG)) != 0)
{
std::cout << *(int*)(tmp) << "非法包头" << std::endl;
memset(tmp, 0, MAX_LEN);
index = 0;
return;
}
else if (index == intLen * 3 && (*(int*)(tmp + intLen * 2) < index || *(int*)(tmp + intLen * 2) > MAX_LEN))
{
std::cout << *(int*)(tmp + intLen) << "长度非法" << std::endl;
memset(tmp, 0, MAX_LEN);
index = 0;
return;
}
else
{
tmp[(index)++] = buf[i];
}
if (index >= intLen * 3 && *(int*)(tmp + intLen * 2) == index)
{
showPackage(tmp);
memset(tmp, 0, MAX_LEN);
index = 0;
}
}
}