基于Python写Socket/Serial收发数据的解包

在收发tcp/ip 或是 com的时候，可能会出现粘包的情况，此时需要解包，代码入下：

def unpack(datas,header,frame_len):
    '''
        根据帧头和长度解包

        datas  总数据包

        header 帧头部信息 bytes

        frame_len 需要解包的帧长
    '''
    if len(header) > len(datas):
        return None
    header_len = len(header) 
    search_count = 0
    locate_list_idx = []
    msg = None
    for index,item in enumerate(datas):
        if item == header[0]:
            if index + frame_len <= len(datas):
                locate_list_idx.append(index)
    if len(locate_list_idx) == 0:
        return None
    for find_idx in locate_list_idx: 
        search_count = 1 
        for looptimes in range(1,header_len): 
            if datas[find_idx + looptimes] == header[looptimes]: 
                search_count += 1
                if search_count == header_len: 
                    msg = datas[find_idx:find_idx + frame_len] 
                    print("解包数据：",msg) 
                    for idx in range((find_idx + frame_len)-1,find_idx-1,-1):  
                        del datas[idx] 
                    return msg
            else:
                break 
    return msg 

测试代码：

test_data = [0x55,0xaa,0x01,0x00,0x00,0x00, 
             0x55,0xaa,0x01,0x00,0x00,0x00, 
             0xff,0x0b,0xf1,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,  
             0x55,0xaa,0x01,0x00,0x00,
             0x55,0xaa,0x01,0x00,0x00,0x00,
             0x55,0xaa,0x01,0x00,0x00,0x00,
             0xff,0x0b,0xf1,0x01,0x00,0x00,0x00,0x00,0x55,0x00,0x00,0x00,0x00,0x00 
             ]  
s = time.time()
while True: 
    msg1 = unpack(test_data,[0x55,0xaa],6)   
    msg2 = unpack(test_data,[0xff,0x0b,0xf1],14)  
    if msg1 == None and msg2 == None: 
        print(time.time() - s )
        break

结果：
解包数据： [85, 170, 1, 0, 0, 0]
解包数据： [255, 11, 241, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
解包数据： [85, 170, 1, 0, 0, 0]
解包数据： [255, 11, 241, 1, 0, 0, 0, 0, 85, 0, 0, 0, 0, 0]
解包数据： [85, 170, 1, 0, 0, 85]
解包数据： [85, 170, 1, 0, 0, 0]
剩余数据： [170, 1, 0, 0, 0]
0.0009965896606445312