Files
allwpilib/ntcore/src/main/native/cpp/Message.h

115 lines
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C++

// Copyright (c) FIRST and other WPILib contributors.
// Open Source Software; you can modify and/or share it under the terms of
// the WPILib BSD license file in the root directory of this project.
#ifndef NTCORE_MESSAGE_H_
#define NTCORE_MESSAGE_H_
#include <functional>
#include <memory>
#include <string>
#include <string_view>
#include "networktables/NetworkTableValue.h"
namespace nt {
class WireDecoder;
class WireEncoder;
class Message {
struct private_init {};
public:
enum MsgType {
kUnknown = -1,
kKeepAlive = 0x00,
kClientHello = 0x01,
kProtoUnsup = 0x02,
kServerHelloDone = 0x03,
kServerHello = 0x04,
kClientHelloDone = 0x05,
kEntryAssign = 0x10,
kEntryUpdate = 0x11,
kFlagsUpdate = 0x12,
kEntryDelete = 0x13,
kClearEntries = 0x14,
kExecuteRpc = 0x20,
kRpcResponse = 0x21
};
using GetEntryTypeFunc = std::function<NT_Type(unsigned int id)>;
Message() = default;
Message(MsgType type, const private_init&) : m_type(type) {}
MsgType type() const { return m_type; }
bool Is(MsgType type) const { return type == m_type; }
// Message data accessors. Callers are responsible for knowing what data is
// actually provided for a particular message.
std::string_view str() const { return m_str; }
std::shared_ptr<Value> value() const { return m_value; }
unsigned int id() const { return m_id; }
unsigned int flags() const { return m_flags; }
unsigned int seq_num_uid() const { return m_seq_num_uid; }
// Read and write from wire representation
void Write(WireEncoder& encoder) const;
static std::shared_ptr<Message> Read(WireDecoder& decoder,
GetEntryTypeFunc get_entry_type);
// Create messages without data
static std::shared_ptr<Message> KeepAlive() {
return std::make_shared<Message>(kKeepAlive, private_init());
}
static std::shared_ptr<Message> ProtoUnsup() {
return std::make_shared<Message>(kProtoUnsup, private_init());
}
static std::shared_ptr<Message> ServerHelloDone() {
return std::make_shared<Message>(kServerHelloDone, private_init());
}
static std::shared_ptr<Message> ClientHelloDone() {
return std::make_shared<Message>(kClientHelloDone, private_init());
}
static std::shared_ptr<Message> ClearEntries() {
return std::make_shared<Message>(kClearEntries, private_init());
}
// Create messages with data
static std::shared_ptr<Message> ClientHello(std::string_view self_id);
static std::shared_ptr<Message> ServerHello(unsigned int flags,
std::string_view self_id);
static std::shared_ptr<Message> EntryAssign(std::string_view name,
unsigned int id,
unsigned int seq_num,
std::shared_ptr<Value> value,
unsigned int flags);
static std::shared_ptr<Message> EntryUpdate(unsigned int id,
unsigned int seq_num,
std::shared_ptr<Value> value);
static std::shared_ptr<Message> FlagsUpdate(unsigned int id,
unsigned int flags);
static std::shared_ptr<Message> EntryDelete(unsigned int id);
static std::shared_ptr<Message> ExecuteRpc(unsigned int id, unsigned int uid,
std::string_view params);
static std::shared_ptr<Message> RpcResponse(unsigned int id, unsigned int uid,
std::string_view result);
Message(const Message&) = delete;
Message& operator=(const Message&) = delete;
private:
MsgType m_type{kUnknown};
// Message data. Use varies by message type.
std::string m_str;
std::shared_ptr<Value> m_value;
unsigned int m_id{0}; // also used for proto_rev
unsigned int m_flags{0};
unsigned int m_seq_num_uid{0};
};
} // namespace nt
#endif // NTCORE_MESSAGE_H_