std::string CTcpCode::Encode(const google::protobuf::Message& message)
{
std::string result;
result.resize(PKGHEAD_FIELD_SIZE); // 预留消息头的前四个字节
// 添加消息类型长度和消息类型具体内容
const std::string& type_name = message.GetTypeName();
int name_len = static_cast<int>(type_name.size()+1);
int be32 = ::htonl(name_len);
result.append(reinterpret_cast<char*>(&be32), sizeof(be32));
result.append(type_name.c_str(), name_len);
// 将protobuf message协议数据添加至result中
bool succeed = message.AppendToString(&result);
if(succeed)
{
// 计算消息体总长度值,并添加至消息头顶部
int len = ::htonl(result.size());
std::copy(reinterpret_cast<char*>(&len), reinterpret_cast<char*>(&len) + sizeof(len), result.begin());
DLOG(INFO) << "encode message ok, name=" << type_name.c_str() << ", len=" << len;
}
else
{
LOG(ERROR) << "encode message error, name=" << type_name.c_str();
result.clear();
}
return result;
}
static void FillBuffer(std::string &buf, const google::protobuf::Message& message)
{
typedef google::protobuf::int32 int32;
const std::string& typeName = message.GetTypeName();
int32 nameLen = static_cast<int32>(typeName.size()+1);
int32 be32 = nameLen;
buf.resize(sizeof(int32) * 2 + nameLen);
buf.append(reinterpret_cast<char*>(&be32), sizeof be32);
buf.append(typeName.c_str(), nameLen);
bool succeed = message.AppendToString(&buf);
if (succeed)
{
const char* begin = buf.c_str() + kHeaderLen;
// CRC32 or adler32 ??
int32 checkSum = 0;//adler32(1, reinterpret_cast<const Bytef*>(begin), result.size()-kHeaderLen);
int32 be32 = checkSum;
buf.append(reinterpret_cast<char*>(&be32), sizeof(be32));
int32 len = buf.size() - kHeaderLen;
int32 &totalLen = *(int32 *)(buf.data());
totalLen = len;
}
else
{
buf.clear();
}
}