diff options
Diffstat (limited to 'src/core/gdbstub')
| -rw-r--r-- | src/core/gdbstub/gdbstub.cpp | 955 | ||||
| -rw-r--r-- | src/core/gdbstub/gdbstub.h | 94 |
2 files changed, 1049 insertions, 0 deletions
diff --git a/src/core/gdbstub/gdbstub.cpp b/src/core/gdbstub/gdbstub.cpp new file mode 100644 index 000000000..003ce4167 --- /dev/null +++ b/src/core/gdbstub/gdbstub.cpp @@ -0,0 +1,955 @@ +// Copyright 2013 Dolphin Emulator Project +// Licensed under GPLv2+ +// Refer to the license.txt file included. + +// Originally written by Sven Peter <sven@fail0verflow.com> for anergistic. + +#include <algorithm> +#include <climits> +#include <csignal> +#include <cstdarg> +#include <cstdio> +#include <cstring> +#include <fcntl.h> +#include <map> +#include <numeric> + +#ifdef _MSC_VER +#include <WinSock2.h> +#include <ws2tcpip.h> +#include <common/x64/abi.h> +#include <io.h> +#include <iphlpapi.h> +#define SHUT_RDWR 2 +#else +#include <unistd.h> +#include <sys/select.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <netinet/in.h> +#endif + +#include "common/logging/log.h" +#include "common/string_util.h" +#include "core/core.h" +#include "core/memory.h" +#include "core/arm/arm_interface.h" +#include "core/gdbstub/gdbstub.h" + +const int GDB_BUFFER_SIZE = 10000; + +const char GDB_STUB_START = '$'; +const char GDB_STUB_END = '#'; +const char GDB_STUB_ACK = '+'; +const char GDB_STUB_NACK = '-'; + +#ifndef SIGTRAP +const u32 SIGTRAP = 5; +#endif + +#ifndef SIGTERM +const u32 SIGTERM = 15; +#endif + +#ifndef MSG_WAITALL +const u32 MSG_WAITALL = 8; +#endif + +const u32 R0_REGISTER = 0; +const u32 R15_REGISTER = 15; +const u32 CSPR_REGISTER = 25; +const u32 FPSCR_REGISTER = 58; +const u32 MAX_REGISTERS = 90; + +namespace GDBStub { + +static int gdbserver_socket = -1; + +static u8 command_buffer[GDB_BUFFER_SIZE]; +static u32 command_length; + +static u32 latest_signal = 0; +static bool step_break = false; +static bool memory_break = false; + +// Binding to a port within the reserved ports range (0-1023) requires root permissions, +// so default to a port outside of that range. +static u16 gdbstub_port = 24689; + +static bool halt_loop = true; +static bool step_loop = false; +std::atomic<bool> g_server_enabled(false); + +#ifdef _WIN32 +WSADATA InitData; +#endif + +struct Breakpoint { + bool active; + PAddr addr; + u32 len; +}; + +static std::map<u32, Breakpoint> breakpoints_execute; +static std::map<u32, Breakpoint> breakpoints_read; +static std::map<u32, Breakpoint> breakpoints_write; + +/** + * Turns hex string character into the equivalent byte. + * + * @param hex Input hex character to be turned into byte. + */ +static u8 HexCharToValue(u8 hex) { + if (hex >= '0' && hex <= '9') { + return hex - '0'; + } else if (hex >= 'a' && hex <= 'f') { + return hex - 'a' + 0xA; + } else if (hex >= 'A' && hex <= 'F') { + return hex - 'A' + 0xA; + } + + LOG_ERROR(Debug_GDBStub, "Invalid nibble: %c (%02x)\n", hex, hex); + return 0; +} + +/** + * Turn nibble of byte into hex string character. + * + * @param n Nibble to be turned into hex character. + */ +static u8 NibbleToHex(u8 n) { + n &= 0xF; + if (n < 0xA) { + return '0' + n; + } else { + return 'A' + n - 0xA; + } +} + +/** +* Converts input hex string characters into an array of equivalent of u8 bytes. +* +* @param dest Pointer to buffer to store u8 bytes. +* @param src Pointer to array of output hex string characters. +* @param len Length of src array. +*/ +static u32 HexToInt(u8* src, u32 len) { + u32 output = 0; + while (len-- > 0) { + output = (output << 4) | HexCharToValue(src[0]); + src++; + } + return output; +} + +/** + * Converts input array of u8 bytes into their equivalent hex string characters. + * + * @param dest Pointer to buffer to store output hex string characters. + * @param src Pointer to array of u8 bytes. + * @param len Length of src array. + */ +static void MemToGdbHex(u8* dest, u8* src, u32 len) { + while (len-- > 0) { + u8 tmp = *src++; + *dest++ = NibbleToHex(tmp >> 4); + *dest++ = NibbleToHex(tmp); + } +} + +/** + * Converts input gdb-formatted hex string characters into an array of equivalent of u8 bytes. + * + * @param dest Pointer to buffer to store u8 bytes. + * @param src Pointer to array of output hex string characters. + * @param len Length of src array. + */ +static void GdbHexToMem(u8* dest, u8* src, u32 len) { + while (len-- > 0) { + *dest++ = (HexCharToValue(src[0]) << 4) | HexCharToValue(src[1]); + src += 2; + } +} + +/** + * Convert a u32 into a gdb-formatted hex string. + * + * @param dest Pointer to buffer to store output hex string characters. + */ +static void IntToGdbHex(u8* dest, u32 v) { + for (int i = 0; i < 8; i += 2) { + dest[i + 1] = NibbleToHex(v >> (4 * i)); + dest[i] = NibbleToHex(v >> (4 * (i + 1))); + } +} + +/** + * Convert a gdb-formatted hex string into a u32. + * + * @param src Pointer to hex string. + */ +static u32 GdbHexToInt(u8* src) { + u32 output = 0; + + for (int i = 0; i < 8; i += 2) { + output = (output << 4) | HexCharToValue(src[7 - i - 1]); + output = (output << 4) | HexCharToValue(src[7 - i]); + } + + return output; +} + +/// Read a byte from the gdb client. +static u8 ReadByte() { + u8 c; + size_t received_size = recv(gdbserver_socket, reinterpret_cast<char*>(&c), 1, MSG_WAITALL); + if (received_size != 1) { + LOG_ERROR(Debug_GDBStub, "recv failed : %ld", received_size); + Shutdown(); + } + + return c; +} + +/// Calculate the checksum of the current command buffer. +static u8 CalculateChecksum(u8 *buffer, u32 length) { + return static_cast<u8>(std::accumulate(buffer, buffer + length, 0, std::plus<u8>())); +} + +/** + * Get the list of breakpoints for a given breakpoint type. + * + * @param type Type of breakpoint list. + */ +static std::map<u32, Breakpoint>& GetBreakpointList(BreakpointType type) { + switch (type) { + case BreakpointType::Execute: + return breakpoints_execute; + case BreakpointType::Read: + return breakpoints_read; + case BreakpointType::Write: + return breakpoints_write; + default: + return breakpoints_read; + } +} + +/** + * Remove the breakpoint from the given address of the specified type. + * + * @param type Type of breakpoint. + * @param addr Address of breakpoint. + */ +static void RemoveBreakpoint(BreakpointType type, PAddr addr) { + std::map<u32, Breakpoint>& p = GetBreakpointList(type); + + auto bp = p.find(addr); + if (bp != p.end()) { + LOG_DEBUG(Debug_GDBStub, "gdb: removed a breakpoint: %08x bytes at %08x of type %d\n", bp->second.len, bp->second.addr, type); + p.erase(addr); + } +} + +BreakpointAddress GetNextBreakpointFromAddress(PAddr addr, BreakpointType type) { + std::map<u32, Breakpoint>& p = GetBreakpointList(type); + auto next_breakpoint = p.lower_bound(addr); + BreakpointAddress breakpoint; + + if (next_breakpoint != p.end()) { + breakpoint.address = next_breakpoint->first; + breakpoint.type = type; + } else { + breakpoint.address = 0; + breakpoint.type = BreakpointType::None; + } + + return breakpoint; +} + +bool CheckBreakpoint(PAddr addr, BreakpointType type) { + if (!IsConnected()) { + return false; + } + + std::map<u32, Breakpoint>& p = GetBreakpointList(type); + + auto bp = p.find(addr); + if (bp != p.end()) { + u32 len = bp->second.len; + + // IDA Pro defaults to 4-byte breakpoints for all non-hardware breakpoints + // no matter if it's a 4-byte or 2-byte instruction. When you execute a + // Thumb instruction with a 4-byte breakpoint set, it will set a breakpoint on + // two instructions instead of the single instruction you placed the breakpoint + // on. So, as a way to make sure that execution breakpoints are only breaking + // on the instruction that was specified, set the length of an execution + // breakpoint to 1. This should be fine since the CPU should never begin executing + // an instruction anywhere except the beginning of the instruction. + if (type == BreakpointType::Execute) { + len = 1; + } + + if (bp->second.active && (addr >= bp->second.addr && addr < bp->second.addr + len)) { + LOG_DEBUG(Debug_GDBStub, "Found breakpoint type %d @ %08x, range: %08x - %08x (%d bytes)\n", type, addr, bp->second.addr, bp->second.addr + len, len); + return true; + } + } + + return false; +} + +/** + * Send packet to gdb client. + * + * @param packet Packet to be sent to client. + */ +static void SendPacket(const char packet) { + size_t sent_size = send(gdbserver_socket, &packet, 1, 0); + if (sent_size != 1) { + LOG_ERROR(Debug_GDBStub, "send failed"); + } +} + +/** + * Send reply to gdb client. + * + * @param reply Reply to be sent to client. + */ +static void SendReply(const char* reply) { + if (!IsConnected()) { + return; + } + + memset(command_buffer, 0, sizeof(command_buffer)); + + command_length = strlen(reply); + if (command_length + 4 > sizeof(command_buffer)) { + LOG_ERROR(Debug_GDBStub, "command_buffer overflow in SendReply"); + return; + } + + memcpy(command_buffer + 1, reply, command_length); + + u8 checksum = CalculateChecksum(command_buffer, command_length + 1); + command_buffer[0] = GDB_STUB_START; + command_buffer[command_length + 1] = GDB_STUB_END; + command_buffer[command_length + 2] = NibbleToHex(checksum >> 4); + command_buffer[command_length + 3] = NibbleToHex(checksum); + + u8* ptr = command_buffer; + u32 left = command_length + 4; + while (left > 0) { + int sent_size = send(gdbserver_socket, reinterpret_cast<char*>(ptr), left, 0); + if (sent_size < 0) { + LOG_ERROR(Debug_GDBStub, "gdb: send failed"); + return Shutdown(); + } + + left -= sent_size; + ptr += sent_size; + } +} + +/// Handle query command from gdb client. +static void HandleQuery() { + LOG_DEBUG(Debug_GDBStub, "gdb: query '%s'\n", command_buffer + 1); + + if (!strcmp(reinterpret_cast<const char*>(command_buffer + 1), "TStatus")) { + SendReply("T0"); + } else { + SendReply(""); + } +} + +/// Handle set thread command from gdb client. +static void HandleSetThread() { + if (memcmp(command_buffer, "Hg0", 3) == 0 || + memcmp(command_buffer, "Hc-1", 4) == 0 || + memcmp(command_buffer, "Hc0", 4) == 0 || + memcmp(command_buffer, "Hc1", 4) == 0) { + return SendReply("OK"); + } + + SendReply("E01"); +} + +/** + * Send signal packet to client. + * + * @param signal Signal to be sent to client. + */ +void SendSignal(u32 signal) { + if (gdbserver_socket == -1) { + return; + } + + latest_signal = signal; + + std::string buffer = Common::StringFromFormat("T%02x%02x:%08x;%02x:%08x;", latest_signal, 15, htonl(Core::g_app_core->GetPC()), 13, htonl(Core::g_app_core->GetReg(13))); + LOG_DEBUG(Debug_GDBStub, "Response: %s", buffer.c_str()); + SendReply(buffer.c_str()); +} + +/// Read command from gdb client. +static void ReadCommand() { + command_length = 0; + memset(command_buffer, 0, sizeof(command_buffer)); + + u8 c = ReadByte(); + if (c == '+') { + //ignore ack + return; + } else if (c == 0x03) { + LOG_INFO(Debug_GDBStub, "gdb: found break command\n"); + halt_loop = true; + SendSignal(SIGTRAP); + return; + } else if (c != GDB_STUB_START) { + LOG_DEBUG(Debug_GDBStub, "gdb: read invalid byte %02x\n", c); + return; + } + + while ((c = ReadByte()) != GDB_STUB_END) { + if (command_length >= sizeof(command_buffer)) { + LOG_ERROR(Debug_GDBStub, "gdb: command_buffer overflow\n"); + SendPacket(GDB_STUB_NACK); + return; + } + command_buffer[command_length++] = c; + } + + u8 checksum_received = HexCharToValue(ReadByte()) << 4; + checksum_received |= HexCharToValue(ReadByte()); + + u8 checksum_calculated = CalculateChecksum(command_buffer, command_length); + + if (checksum_received != checksum_calculated) { + LOG_ERROR(Debug_GDBStub, "gdb: invalid checksum: calculated %02x and read %02x for $%s# (length: %d)\n", + checksum_calculated, checksum_received, command_buffer, command_length); + + command_length = 0; + + SendPacket(GDB_STUB_NACK); + return; + } + + SendPacket(GDB_STUB_ACK); +} + +/// Check if there is data to be read from the gdb client. +static bool IsDataAvailable() { + if (!IsConnected()) { + return false; + } + + fd_set fd_socket; + + FD_ZERO(&fd_socket); + FD_SET(gdbserver_socket, &fd_socket); + + struct timeval t; + t.tv_sec = 0; + t.tv_usec = 0; + + if (select(gdbserver_socket + 1, &fd_socket, nullptr, nullptr, &t) < 0) { + LOG_ERROR(Debug_GDBStub, "select failed"); + return false; + } + + return FD_ISSET(gdbserver_socket, &fd_socket); +} + +/// Send requested register to gdb client. +static void ReadRegister() { + static u8 reply[64]; + memset(reply, 0, sizeof(reply)); + + u32 id = HexCharToValue(command_buffer[1]); + if (command_buffer[2] != '\0') { + id <<= 4; + id |= HexCharToValue(command_buffer[2]); + } + + if (id >= R0_REGISTER && id <= R15_REGISTER) { + IntToGdbHex(reply, Core::g_app_core->GetReg(id)); + } else if (id == CSPR_REGISTER) { + IntToGdbHex(reply, Core::g_app_core->GetCPSR()); + } else if (id > CSPR_REGISTER && id < FPSCR_REGISTER) { + IntToGdbHex(reply, Core::g_app_core->GetVFPReg(id - CSPR_REGISTER - 1)); // VFP registers should start at 26, so one after CSPR_REGISTER + } else if (id == FPSCR_REGISTER) { + IntToGdbHex(reply, Core::g_app_core->GetVFPSystemReg(VFP_FPSCR)); // Get FPSCR + IntToGdbHex(reply + 8, 0); + } else { + return SendReply("E01"); + } + + SendReply(reinterpret_cast<char*>(reply)); +} + +/// Send all registers to the gdb client. +static void ReadRegisters() { + static u8 buffer[GDB_BUFFER_SIZE - 4]; + memset(buffer, 0, sizeof(buffer)); + + u8* bufptr = buffer; + for (int i = 0, reg = 0; i <= MAX_REGISTERS; i++, reg++) { + if (i <= R15_REGISTER) { + IntToGdbHex(bufptr + i * CHAR_BIT, Core::g_app_core->GetReg(reg)); + } else if (i == CSPR_REGISTER) { + IntToGdbHex(bufptr + i * CHAR_BIT, Core::g_app_core->GetCPSR()); + } else if (i < CSPR_REGISTER) { + IntToGdbHex(bufptr + i * CHAR_BIT, 0); + IntToGdbHex(bufptr + (i + 1) * CHAR_BIT, 0); + i++; // These registers seem to be all 64bit instead of 32bit, so skip two instead of one + reg++; + } else if (i > CSPR_REGISTER && i < MAX_REGISTERS) { + IntToGdbHex(bufptr + i * CHAR_BIT, Core::g_app_core->GetVFPReg(reg - CSPR_REGISTER - 1)); + IntToGdbHex(bufptr + (i + 1) * CHAR_BIT, 0); + i++; + } else if (i == MAX_REGISTERS) { + IntToGdbHex(bufptr + i * CHAR_BIT, Core::g_app_core->GetVFPSystemReg(VFP_FPSCR)); + } + } + + SendReply(reinterpret_cast<char*>(buffer)); +} + +/// Modify data of register specified by gdb client. +static void WriteRegister() { + u8* buffer_ptr = command_buffer + 3; + + u32 id = HexCharToValue(command_buffer[1]); + if (command_buffer[2] != '=') { + ++buffer_ptr; + id <<= 4; + id |= HexCharToValue(command_buffer[2]); + } + + if (id >= R0_REGISTER && id <= R15_REGISTER) { + Core::g_app_core->SetReg(id, GdbHexToInt(buffer_ptr)); + } else if (id == CSPR_REGISTER) { + Core::g_app_core->SetCPSR(GdbHexToInt(buffer_ptr)); + } else if (id > CSPR_REGISTER && id < FPSCR_REGISTER) { + Core::g_app_core->SetVFPReg(id - CSPR_REGISTER - 1, GdbHexToInt(buffer_ptr)); + } else if (id == FPSCR_REGISTER) { + Core::g_app_core->SetVFPSystemReg(VFP_FPSCR, GdbHexToInt(buffer_ptr)); + } else { + return SendReply("E01"); + } + + SendReply("OK"); +} + +/// Modify all registers with data received from the client. +static void WriteRegisters() { + u8* buffer_ptr = command_buffer + 1; + + if (command_buffer[0] != 'G') + return SendReply("E01"); + + for (int i = 0, reg = 0; i <= MAX_REGISTERS; i++, reg++) { + if (i <= R15_REGISTER) { + Core::g_app_core->SetReg(reg, GdbHexToInt(buffer_ptr + i * CHAR_BIT)); + } else if (i == CSPR_REGISTER) { + Core::g_app_core->SetCPSR(GdbHexToInt(buffer_ptr + i * CHAR_BIT)); + } else if (i < CSPR_REGISTER) { + i++; // These registers seem to be all 64bit instead of 32bit, so skip two instead of one + reg++; + } else if (i > CSPR_REGISTER && i < MAX_REGISTERS) { + Core::g_app_core->SetVFPReg(reg - CSPR_REGISTER - 1, GdbHexToInt(buffer_ptr + i * CHAR_BIT)); + i++; // Skip padding + } else if (i == MAX_REGISTERS) { + Core::g_app_core->SetVFPSystemReg(VFP_FPSCR, GdbHexToInt(buffer_ptr + i * CHAR_BIT)); + } + } + + SendReply("OK"); +} + +/// Read location in memory specified by gdb client. +static void ReadMemory() { + static u8 reply[GDB_BUFFER_SIZE - 4]; + + auto start_offset = command_buffer+1; + auto addr_pos = std::find(start_offset, command_buffer+command_length, ','); + PAddr addr = HexToInt(start_offset, addr_pos - start_offset); + + start_offset = addr_pos+1; + u32 len = HexToInt(start_offset, (command_buffer + command_length) - start_offset); + + LOG_DEBUG(Debug_GDBStub, "gdb: addr: %08x len: %08x\n", addr, len); + + if (len * 2 > sizeof(reply)) { + SendReply("E01"); + } + + u8* data = Memory::GetPointer(addr); + if (!data) { + return SendReply("E0"); + } + + MemToGdbHex(reply, data, len); + reply[len * 2] = '\0'; + SendReply(reinterpret_cast<char*>(reply)); +} + +/// Modify location in memory with data received from the gdb client. +static void WriteMemory() { + auto start_offset = command_buffer+1; + auto addr_pos = std::find(start_offset, command_buffer+command_length, ','); + PAddr addr = HexToInt(start_offset, addr_pos - start_offset); + + start_offset = addr_pos+1; + auto len_pos = std::find(start_offset, command_buffer+command_length, ':'); + u32 len = HexToInt(start_offset, len_pos - start_offset); + + u8* dst = Memory::GetPointer(addr); + if (!dst) { + return SendReply("E00"); + } + + GdbHexToMem(dst, len_pos + 1, len); + SendReply("OK"); +} + +void Break(bool is_memory_break) { + if (!halt_loop) { + halt_loop = true; + SendSignal(SIGTRAP); + } + + memory_break = is_memory_break; +} + +/// Tell the CPU that it should perform a single step. +static void Step() { + step_loop = true; + halt_loop = true; + step_break = true; + SendSignal(SIGTRAP); +} + +bool IsMemoryBreak() { + if (IsConnected()) { + return false; + } + + return memory_break; +} + +/// Tell the CPU to continue executing. +static void Continue() { + memory_break = false; + step_break = false; + step_loop = false; + halt_loop = false; +} + +/** + * Commit breakpoint to list of breakpoints. + * + * @param type Type of breakpoint. + * @param addr Address of breakpoint. + * @param len Length of breakpoint. + */ +bool CommitBreakpoint(BreakpointType type, PAddr addr, u32 len) { + std::map<u32, Breakpoint>& p = GetBreakpointList(type); + + Breakpoint breakpoint; + breakpoint.active = true; + breakpoint.addr = addr; + breakpoint.len = len; + p.insert({ addr, breakpoint }); + + LOG_DEBUG(Debug_GDBStub, "gdb: added %d breakpoint: %08x bytes at %08x\n", type, breakpoint.len, breakpoint.addr); + + return true; +} + +/// Handle add breakpoint command from gdb client. +static void AddBreakpoint() { + BreakpointType type; + + u8 type_id = HexCharToValue(command_buffer[1]); + switch (type_id) { + case 0: + case 1: + type = BreakpointType::Execute; + break; + case 2: + type = BreakpointType::Write; + break; + case 3: + type = BreakpointType::Read; + break; + case 4: + type = BreakpointType::Access; + break; + default: + return SendReply("E01"); + } + + auto start_offset = command_buffer+3; + auto addr_pos = std::find(start_offset, command_buffer+command_length, ','); + PAddr addr = HexToInt(start_offset, addr_pos - start_offset); + + start_offset = addr_pos+1; + u32 len = HexToInt(start_offset, (command_buffer + command_length) - start_offset); + + if (type == BreakpointType::Access) { + // Access is made up of Read and Write types, so add both breakpoints + type = BreakpointType::Read; + + if (!CommitBreakpoint(type, addr, len)) { + return SendReply("E02"); + } + + type = BreakpointType::Write; + } + + if (!CommitBreakpoint(type, addr, len)) { + return SendReply("E02"); + } + + SendReply("OK"); +} + +/// Handle remove breakpoint command from gdb client. +static void RemoveBreakpoint() { + BreakpointType type; + + u8 type_id = HexCharToValue(command_buffer[1]); + switch (type_id) { + case 0: + case 1: + type = BreakpointType::Execute; + break; + case 2: + type = BreakpointType::Write; + break; + case 3: + type = BreakpointType::Read; + break; + case 4: + type = BreakpointType::Access; + break; + default: + return SendReply("E01"); + } + + auto start_offset = command_buffer+3; + auto addr_pos = std::find(start_offset, command_buffer+command_length, ','); + PAddr addr = HexToInt(start_offset, addr_pos - start_offset); + + start_offset = addr_pos+1; + u32 len = HexToInt(start_offset, (command_buffer + command_length) - start_offset); + + if (type == BreakpointType::Access) { + // Access is made up of Read and Write types, so add both breakpoints + type = BreakpointType::Read; + RemoveBreakpoint(type, addr); + + type = BreakpointType::Write; + } + + RemoveBreakpoint(type, addr); + SendReply("OK"); +} + +void HandlePacket() { + if (!IsConnected()) { + return; + } + + if (!IsDataAvailable()) { + return; + } + + ReadCommand(); + if (command_length == 0) { + return; + } + + LOG_DEBUG(Debug_GDBStub, "Packet: %s", command_buffer); + + switch (command_buffer[0]) { + case 'q': + HandleQuery(); + break; + case 'H': + HandleSetThread(); + break; + case '?': + SendSignal(latest_signal); + break; + case 'k': + Shutdown(); + LOG_INFO(Debug_GDBStub, "killed by gdb"); + return; + case 'g': + ReadRegisters(); + break; + case 'G': + WriteRegisters(); + break; + case 'p': + ReadRegister(); + break; + case 'P': + WriteRegister(); + break; + case 'm': + ReadMemory(); + break; + case 'M': + WriteMemory(); + break; + case 's': + Step(); + return; + case 'C': + case 'c': + Continue(); + return; + case 'z': + RemoveBreakpoint(); + break; + case 'Z': + AddBreakpoint(); + break; + default: + SendReply(""); + break; + } +} + +void SetServerPort(u16 port) { + gdbstub_port = port; +} + +void ToggleServer(bool status) { + if (status) { + g_server_enabled = status; + + // Start server + if (!IsConnected() && Core::g_sys_core != nullptr) { + Init(); + } + } + else { + // Stop server + if (IsConnected()) { + Shutdown(); + } + + g_server_enabled = status; + } +} + +void Init(u16 port) { + if (!g_server_enabled) { + // Set the halt loop to false in case the user enabled the gdbstub mid-execution. + // This way the CPU can still execute normally. + halt_loop = false; + step_loop = false; + return; + } + + // Setup initial gdbstub status + halt_loop = true; + step_loop = false; + + breakpoints_execute.clear(); + breakpoints_read.clear(); + breakpoints_write.clear(); + + // Start gdb server + LOG_INFO(Debug_GDBStub, "Starting GDB server on port %d...", port); + + sockaddr_in saddr_server = {}; + saddr_server.sin_family = AF_INET; + saddr_server.sin_port = htons(port); + saddr_server.sin_addr.s_addr = INADDR_ANY; + +#ifdef _WIN32 + WSAStartup(MAKEWORD(2, 2), &InitData); +#endif + + int tmpsock = socket(PF_INET, SOCK_STREAM, 0); + if (tmpsock == -1) { + LOG_ERROR(Debug_GDBStub, "Failed to create gdb socket"); + } + + const sockaddr* server_addr = reinterpret_cast<const sockaddr*>(&saddr_server); + socklen_t server_addrlen = sizeof(saddr_server); + if (bind(tmpsock, server_addr, server_addrlen) < 0) { + LOG_ERROR(Debug_GDBStub, "Failed to bind gdb socket"); + } + + if (listen(tmpsock, 1) < 0) { + LOG_ERROR(Debug_GDBStub, "Failed to listen to gdb socket"); + } + + // Wait for gdb to connect + LOG_INFO(Debug_GDBStub, "Waiting for gdb to connect...\n"); + sockaddr_in saddr_client; + sockaddr* client_addr = reinterpret_cast<sockaddr*>(&saddr_client); + socklen_t client_addrlen = sizeof(saddr_client); + gdbserver_socket = accept(tmpsock, client_addr, &client_addrlen); + if (gdbserver_socket < 0) { + // In the case that we couldn't start the server for whatever reason, just start CPU execution like normal. + halt_loop = false; + step_loop = false; + + LOG_ERROR(Debug_GDBStub, "Failed to accept gdb client"); + } + else { + LOG_INFO(Debug_GDBStub, "Client connected.\n"); + saddr_client.sin_addr.s_addr = ntohl(saddr_client.sin_addr.s_addr); + } + + // Clean up temporary socket if it's still alive at this point. + if (tmpsock != -1) { + shutdown(tmpsock, SHUT_RDWR); + } +} + +void Init() { + Init(gdbstub_port); +} + +void Shutdown() { + if (!g_server_enabled) { + return; + } + + LOG_INFO(Debug_GDBStub, "Stopping GDB ..."); + if (gdbserver_socket != -1) { + shutdown(gdbserver_socket, SHUT_RDWR); + gdbserver_socket = -1; + } + +#ifdef _WIN32 + WSACleanup(); +#endif + + LOG_INFO(Debug_GDBStub, "GDB stopped."); +} + +bool IsConnected() { + return g_server_enabled && gdbserver_socket != -1; +} + +bool GetCpuHaltFlag() { + return halt_loop; +} + +bool GetCpuStepFlag() { + return step_loop; +} + +void SetCpuStepFlag(bool is_step) { + step_loop = is_step; +} + +}; diff --git a/src/core/gdbstub/gdbstub.h b/src/core/gdbstub/gdbstub.h new file mode 100644 index 000000000..aff705a32 --- /dev/null +++ b/src/core/gdbstub/gdbstub.h @@ -0,0 +1,94 @@ +// Copyright 2013 Dolphin Emulator Project +// Licensed under GPLv2+ +// Refer to the license.txt file included. + +// Originally written by Sven Peter <sven@fail0verflow.com> for anergistic. + +#pragma once +#include <atomic> + +namespace GDBStub { + +/// Breakpoint Method +enum class BreakpointType { + None, ///< None + Execute, ///< Execution Breakpoint + Read, ///< Read Breakpoint + Write, ///< Write Breakpoint + Access ///< Access (R/W) Breakpoint +}; + +struct BreakpointAddress { + PAddr address; + BreakpointType type; +}; + +/// If set to false, the server will never be started and no gdbstub-related functions will be executed. +extern std::atomic<bool> g_server_enabled; + +/** + * Set the port the gdbstub should use to listen for connections. + * + * @param port Port to listen for connection + */ +void SetServerPort(u16 port); + +/** + * Set the g_server_enabled flag and start or stop the server if possible. + * + * @param status Set the server to enabled or disabled. + */ +void ToggleServer(bool status); + +/// Start the gdbstub server. +void Init(); + +/// Stop gdbstub server. +void Shutdown(); + +/// Returns true if there is an active socket connection. +bool IsConnected(); + +/** + * Signal to the gdbstub server that it should halt CPU execution. + * + * @param is_memory_break If true, the break resulted from a memory breakpoint. + */ +void Break(bool is_memory_break = false); + +/// Determine if there was a memory breakpoint. +bool IsMemoryBreak(); + +/// Read and handle packet from gdb client. +void HandlePacket(); + +/** + * Get the nearest breakpoint of the specified type at the given address. + * + * @param addr Address to search from. + * @param type Type of breakpoint. + */ +BreakpointAddress GetNextBreakpointFromAddress(u32 addr, GDBStub::BreakpointType type); + +/** + * Check if a breakpoint of the specified type exists at the given address. + * + * @param addr Address of breakpoint. + * @param type Type of breakpoint. + */ +bool CheckBreakpoint(u32 addr, GDBStub::BreakpointType type); + +// If set to true, the CPU will halt at the beginning of the next CPU loop. +bool GetCpuHaltFlag(); + +// If set to true and the CPU is halted, the CPU will step one instruction. +bool GetCpuStepFlag(); + +/** + * When set to true, the CPU will step one instruction when the CPU is halted next. + * + * @param is_step + */ +void SetCpuStepFlag(bool is_step); + +} |