GDBDebugServer.h

#pragma once

#ifdef WITH_GDB_DEBUGGER

#include "Thread.h"
#include <Emu/IdManager.h>
#include "Emu/CPU/CPUThread.h"
#include "Emu/Cell/PPUThread.h"

#ifdef _WIN32
#include <winsock2.h>
#include <WS2tcpip.h>
#else
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <unistd.h>
#endif

#ifdef _WIN32
using socket_t = SOCKET;
#else
using socket_t = int;
#endif

typedef struct gdb_cmd {
	std::string cmd;
	std::string data;
	u8 checksum;
} gdb_cmd;

class wrong_checksum_exception : public std::runtime_error {
public:
	wrong_checksum_exception(char const* const message) : runtime_error(message) {}
};

const u64 ALL_THREADS = 0xffffffffffffffff;
const u64 ANY_THREAD = 0;

class GDBDebugServer : public named_thread {

	socket_t server_socket;
	socket_t client_socket;
	std::weak_ptr<cpu_thread> selected_thread;
	u64 continue_ops_thread_id = ANY_THREAD;
	u64 general_ops_thread_id = ANY_THREAD;

	//initialize server socket and start listening
	void start_server();
	//read at most cnt bytes to buf, returns nubmer of bytes actually read
	int read(void* buf, int cnt);
	//reads one character
	char read_char();
	//reads pairs of hex characters and returns their integer value
	u8 read_hexbyte();
	//tries to read command, throws exceptions if anything goes wrong
	void try_read_cmd(gdb_cmd& out_cmd);
	//reads commands until receiveing one with valid checksum
	//in case of other exception (i.e. wrong first char of command)
	//it will log exception text and return false 
	//in that case best for caller would be to stop reading, because 
	//chance of getting correct command is low
	bool read_cmd(gdb_cmd& out_cmd);
	//send cnt bytes from buf to client
	void send(const char* buf, int cnt);
	//send character to client
	void send_char(char c);
	//acknowledge packet, either as accepted or declined
	void ack(bool accepted);
	//sends command body cmd to client
	void send_cmd(const std::string & cmd);
	//sends command to client until receives positive acknowledgement
	//returns false in case some error happened, and command wasn't sent
	bool send_cmd_ack(const std::string & cmd);
	//appends encoded char c to string str, and returns checksum. encoded byte can occupy 2 bytes
	static u8 append_encoded_char(char c, std::string& str);
	//convert u8 to 2 byte hexademical representation
	static std::string to_hexbyte(u8 i);
	//choose thread, support ALL_THREADS and ANY_THREAD values, returns true if some thread was selected
	bool select_thread(u64 id);
	//returns register value as hex string by register id (in gdb), in case of wrong id returns empty string
	static std::string get_reg(std::shared_ptr<ppu_thread> thread, u32 rid);
	//sets register value to hex string by register id (in gdb), in case of wrong id returns false
	static bool set_reg(std::shared_ptr<ppu_thread> thread, u32 rid, std::string value);
	//returns size of register with id rid in bytes, zero if invalid rid is provided
	static u32 get_reg_size(std::shared_ptr<ppu_thread> thread, u32 rid);
	//send reason of stop, returns false if sending response failed
	bool send_reason();

	//commands
	bool cmd_extended_mode(gdb_cmd& cmd);
	bool cmd_reason(gdb_cmd& cmd);
	bool cmd_supported(gdb_cmd& cmd);
	bool cmd_thread_info(gdb_cmd& cmd);
	bool cmd_current_thread(gdb_cmd& cmd);
	bool cmd_read_register(gdb_cmd& cmd);
	bool cmd_write_register(gdb_cmd& cmd);
	bool cmd_read_memory(gdb_cmd& cmd);
	bool cmd_write_memory(gdb_cmd& cmd);
	bool cmd_read_all_registers(gdb_cmd& cmd);
	bool cmd_write_all_registers(gdb_cmd& cmd);
	bool cmd_set_thread_ops(gdb_cmd& cmd);
	bool cmd_attached_to_what(gdb_cmd& cmd);
	bool cmd_kill(gdb_cmd& cmd);
	bool cmd_continue_support(gdb_cmd& cmd);
	bool cmd_vcont(gdb_cmd& cmd);
	bool cmd_set_breakpoint(gdb_cmd& cmd);
	bool cmd_remove_breakpoint(gdb_cmd& cmd);

protected:
	void on_task() override final;
	void on_exit() override final;

public:
	static const u32 id_base = 1;
	static const u32 id_step = 1;
	static const u32 id_count = 0x100000;

	bool from_breakpoint = true;
	bool stop = false;

	virtual std::string get_name() const;
	virtual void on_stop() override final;
};

extern u32 g_gdb_debugger_id;

#endif