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); + +} | 
