Archipelago » qemu

/*

 * gdb server stub

 *

 * Copyright (c) 2003-2005 Fabrice Bellard

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see <http://www.gnu.org/licenses/>.

 */

#include "config.h"

#include "qemu-common.h"

#ifdef CONFIG_USER_ONLY

#include <stdlib.h>

#include <stdio.h>

#include <stdarg.h>

#include <string.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

#include "qemu.h"

#else

#include "monitor/monitor.h"

#include "sysemu/char.h"

#include "sysemu/sysemu.h"

#include "exec/gdbstub.h"

#endif

#define MAX_PACKET_LENGTH 4096

#include "cpu.h"

#include "qemu/sockets.h"

#include "sysemu/kvm.h"

#include "qemu/bitops.h"

static inline int target_memory_rw_debug(CPUState *cpu, target_ulong addr,

                                         uint8_t *buf, int len, bool is_write)

{

    CPUClass *cc = CPU_GET_CLASS(cpu);

    if (cc->memory_rw_debug) {

        return cc->memory_rw_debug(cpu, addr, buf, len, is_write);

    }

    return cpu_memory_rw_debug(cpu, addr, buf, len, is_write);

}

enum {

    GDB_SIGNAL_0 = 0,

    GDB_SIGNAL_INT = 2,

    GDB_SIGNAL_QUIT = 3,

    GDB_SIGNAL_TRAP = 5,

    GDB_SIGNAL_ABRT = 6,

    GDB_SIGNAL_ALRM = 14,

    GDB_SIGNAL_IO = 23,

    GDB_SIGNAL_XCPU = 24,

    GDB_SIGNAL_UNKNOWN = 143

};

#ifdef CONFIG_USER_ONLY

/* Map target signal numbers to GDB protocol signal numbers and vice

 * versa.  For user emulation's currently supported systems, we can

 * assume most signals are defined.

 */

static int gdb_signal_table[] = {

    0,

    TARGET_SIGHUP,

    TARGET_SIGINT,

    TARGET_SIGQUIT,

    TARGET_SIGILL,

    TARGET_SIGTRAP,

    TARGET_SIGABRT,

    -1, /* SIGEMT */

    TARGET_SIGFPE,

    TARGET_SIGKILL,

    TARGET_SIGBUS,

    TARGET_SIGSEGV,

    TARGET_SIGSYS,

    TARGET_SIGPIPE,

    TARGET_SIGALRM,

    TARGET_SIGTERM,

    TARGET_SIGURG,

    TARGET_SIGSTOP,

    TARGET_SIGTSTP,

    TARGET_SIGCONT,

    TARGET_SIGCHLD,

    TARGET_SIGTTIN,

    TARGET_SIGTTOU,

    TARGET_SIGIO,

    TARGET_SIGXCPU,

    TARGET_SIGXFSZ,

    TARGET_SIGVTALRM,

    TARGET_SIGPROF,

    TARGET_SIGWINCH,

    -1, /* SIGLOST */

    TARGET_SIGUSR1,

    TARGET_SIGUSR2,

#ifdef TARGET_SIGPWR

    TARGET_SIGPWR,

#else

    -1,

#endif

    -1, /* SIGPOLL */

    -1,

    -1,

    -1,

    -1,

    -1,

    -1,

    -1,

    -1,

    -1,

    -1,

    -1,

#ifdef __SIGRTMIN

    __SIGRTMIN + 1,

    __SIGRTMIN + 2,

    __SIGRTMIN + 3,

    __SIGRTMIN + 4,

    __SIGRTMIN + 5,

    __SIGRTMIN + 6,

    __SIGRTMIN + 7,

    __SIGRTMIN + 8,

    __SIGRTMIN + 9,

    __SIGRTMIN + 10,

    __SIGRTMIN + 11,

    __SIGRTMIN + 12,

    __SIGRTMIN + 13,

    __SIGRTMIN + 14,

    __SIGRTMIN + 15,

    __SIGRTMIN + 16,

    __SIGRTMIN + 17,

    __SIGRTMIN + 18,

    __SIGRTMIN + 19,

    __SIGRTMIN + 20,

    __SIGRTMIN + 21,

    __SIGRTMIN + 22,

    __SIGRTMIN + 23,

    __SIGRTMIN + 24,

    __SIGRTMIN + 25,

    __SIGRTMIN + 26,

    __SIGRTMIN + 27,

    __SIGRTMIN + 28,

    __SIGRTMIN + 29,

    __SIGRTMIN + 30,

    __SIGRTMIN + 31,

    -1, /* SIGCANCEL */

    __SIGRTMIN,

    __SIGRTMIN + 32,

    __SIGRTMIN + 33,

    __SIGRTMIN + 34,

    __SIGRTMIN + 35,

    __SIGRTMIN + 36,

    __SIGRTMIN + 37,

    __SIGRTMIN + 38,

    __SIGRTMIN + 39,

    __SIGRTMIN + 40,

    __SIGRTMIN + 41,

    __SIGRTMIN + 42,

    __SIGRTMIN + 43,

    __SIGRTMIN + 44,

    __SIGRTMIN + 45,

    __SIGRTMIN + 46,

    __SIGRTMIN + 47,

    __SIGRTMIN + 48,

    __SIGRTMIN + 49,

    __SIGRTMIN + 50,

    __SIGRTMIN + 51,

    __SIGRTMIN + 52,

    __SIGRTMIN + 53,

    __SIGRTMIN + 54,

    __SIGRTMIN + 55,

    __SIGRTMIN + 56,

    __SIGRTMIN + 57,

    __SIGRTMIN + 58,

    __SIGRTMIN + 59,

    __SIGRTMIN + 60,

    __SIGRTMIN + 61,

    __SIGRTMIN + 62,

    __SIGRTMIN + 63,

    __SIGRTMIN + 64,

    __SIGRTMIN + 65,

    __SIGRTMIN + 66,

    __SIGRTMIN + 67,

    __SIGRTMIN + 68,

    __SIGRTMIN + 69,

    __SIGRTMIN + 70,

    __SIGRTMIN + 71,

    __SIGRTMIN + 72,

    __SIGRTMIN + 73,

    __SIGRTMIN + 74,

    __SIGRTMIN + 75,

    __SIGRTMIN + 76,

    __SIGRTMIN + 77,

    __SIGRTMIN + 78,

    __SIGRTMIN + 79,

    __SIGRTMIN + 80,

    __SIGRTMIN + 81,

    __SIGRTMIN + 82,

    __SIGRTMIN + 83,

    __SIGRTMIN + 84,

    __SIGRTMIN + 85,

    __SIGRTMIN + 86,

    __SIGRTMIN + 87,

    __SIGRTMIN + 88,

    __SIGRTMIN + 89,

    __SIGRTMIN + 90,

    __SIGRTMIN + 91,

    __SIGRTMIN + 92,

    __SIGRTMIN + 93,

    __SIGRTMIN + 94,

    __SIGRTMIN + 95,

    -1, /* SIGINFO */

    -1, /* UNKNOWN */

    -1, /* DEFAULT */

    -1,

    -1,

    -1,

    -1,

    -1,

    -1

#endif

};

#else

/* In system mode we only need SIGINT and SIGTRAP; other signals

   are not yet supported.  */

enum {

    TARGET_SIGINT = 2,

    TARGET_SIGTRAP = 5

};

static int gdb_signal_table[] = {

    -1,

    -1,

    TARGET_SIGINT,

    -1,

    -1,

    TARGET_SIGTRAP

};

#endif

#ifdef CONFIG_USER_ONLY

static int target_signal_to_gdb (int sig)

{

    int i;

    for (i = 0; i < ARRAY_SIZE (gdb_signal_table); i++)

        if (gdb_signal_table[i] == sig)

            return i;

    return GDB_SIGNAL_UNKNOWN;

}

#endif

static int gdb_signal_to_target (int sig)

{

    if (sig < ARRAY_SIZE (gdb_signal_table))

        return gdb_signal_table[sig];

    else

        return -1;

}

//#define DEBUG_GDB

typedef struct GDBRegisterState {

    int base_reg;

    int num_regs;

    gdb_reg_cb get_reg;

    gdb_reg_cb set_reg;

    const char *xml;

    struct GDBRegisterState *next;

} GDBRegisterState;

enum RSState {

    RS_INACTIVE,

    RS_IDLE,

    RS_GETLINE,

    RS_CHKSUM1,

    RS_CHKSUM2,

};

typedef struct GDBState {

    CPUState *c_cpu; /* current CPU for step/continue ops */

    CPUState *g_cpu; /* current CPU for other ops */

    CPUState *query_cpu; /* for q{f|s}ThreadInfo */

    enum RSState state; /* parsing state */

    char line_buf[MAX_PACKET_LENGTH];

    int line_buf_index;

    int line_csum;

    uint8_t last_packet[MAX_PACKET_LENGTH + 4];

    int last_packet_len;

    int signal;

#ifdef CONFIG_USER_ONLY

    int fd;

    int running_state;

#else

    CharDriverState *chr;

    CharDriverState *mon_chr;

#endif

    char syscall_buf[256];

    gdb_syscall_complete_cb current_syscall_cb;

} GDBState;

/* By default use no IRQs and no timers while single stepping so as to

 * make single stepping like an ICE HW step.

 */

static int sstep_flags = SSTEP_ENABLE|SSTEP_NOIRQ|SSTEP_NOTIMER;

static GDBState *gdbserver_state;

/* This is an ugly hack to cope with both new and old gdb.

   If gdb sends qXfer:features:read then assume we're talking to a newish

   gdb that understands target descriptions.  */

static int gdb_has_xml;

#ifdef CONFIG_USER_ONLY

/* XXX: This is not thread safe.  Do we care?  */

static int gdbserver_fd = -1;

static int get_char(GDBState *s)

{

    uint8_t ch;

    int ret;

    for(;;) {

        ret = qemu_recv(s->fd, &ch, 1, 0);

        if (ret < 0) {

            if (errno == ECONNRESET)

                s->fd = -1;

            if (errno != EINTR && errno != EAGAIN)

                return -1;

        } else if (ret == 0) {

            close(s->fd);

            s->fd = -1;

            return -1;

        } else {

            break;

        }

    }

    return ch;

}

#endif

static enum {

    GDB_SYS_UNKNOWN,

    GDB_SYS_ENABLED,

    GDB_SYS_DISABLED,

} gdb_syscall_mode;

/* If gdb is connected when the first semihosting syscall occurs then use

   remote gdb syscalls.  Otherwise use native file IO.  */

int use_gdb_syscalls(void)

{

    if (gdb_syscall_mode == GDB_SYS_UNKNOWN) {

        gdb_syscall_mode = (gdbserver_state ? GDB_SYS_ENABLED

                                            : GDB_SYS_DISABLED);

    }

    return gdb_syscall_mode == GDB_SYS_ENABLED;

}

/* Resume execution.  */

static inline void gdb_continue(GDBState *s)

{

#ifdef CONFIG_USER_ONLY

    s->running_state = 1;

#else

    if (runstate_check(RUN_STATE_GUEST_PANICKED)) {

        runstate_set(RUN_STATE_DEBUG);

    }

    if (!runstate_needs_reset()) {

        vm_start();

    }

#endif

}

static void put_buffer(GDBState *s, const uint8_t *buf, int len)

{

#ifdef CONFIG_USER_ONLY

    int ret;

    while (len > 0) {

        ret = send(s->fd, buf, len, 0);

        if (ret < 0) {

            if (errno != EINTR && errno != EAGAIN)

                return;

        } else {

            buf += ret;

            len -= ret;

        }

    }

#else

    qemu_chr_fe_write(s->chr, buf, len);

#endif

}

static inline int fromhex(int v)

{

    if (v >= '0' && v <= '9')

        return v - '0';

    else if (v >= 'A' && v <= 'F')

        return v - 'A' + 10;

    else if (v >= 'a' && v <= 'f')

        return v - 'a' + 10;

    else

        return 0;

}

static inline int tohex(int v)

{

    if (v < 10)

        return v + '0';

    else

        return v - 10 + 'a';

}

static void memtohex(char *buf, const uint8_t *mem, int len)

{

    int i, c;

    char *q;

    q = buf;

    for(i = 0; i < len; i++) {

        c = mem[i];

        *q++ = tohex(c >> 4);

        *q++ = tohex(c & 0xf);

    }

    *q = '\0';

}

static void hextomem(uint8_t *mem, const char *buf, int len)

{

    int i;

    for(i = 0; i < len; i++) {

        mem[i] = (fromhex(buf[0]) << 4) | fromhex(buf[1]);

        buf += 2;

    }

}

/* return -1 if error, 0 if OK */

static int put_packet_binary(GDBState *s, const char *buf, int len)

{

    int csum, i;

    uint8_t *p;

    for(;;) {

        p = s->last_packet;

        *(p++) = '$';

        memcpy(p, buf, len);

        p += len;

        csum = 0;

        for(i = 0; i < len; i++) {

            csum += buf[i];

        }

        *(p++) = '#';

        *(p++) = tohex((csum >> 4) & 0xf);

        *(p++) = tohex((csum) & 0xf);

        s->last_packet_len = p - s->last_packet;

        put_buffer(s, (uint8_t *)s->last_packet, s->last_packet_len);

#ifdef CONFIG_USER_ONLY

        i = get_char(s);

        if (i < 0)

            return -1;

        if (i == '+')

            break;

#else

        break;

#endif

    }

    return 0;

}

/* return -1 if error, 0 if OK */

static int put_packet(GDBState *s, const char *buf)

{

#ifdef DEBUG_GDB

    printf("reply='%s'\n", buf);

#endif

    return put_packet_binary(s, buf, strlen(buf));

}

#if defined(TARGET_I386)

#include "target-i386/gdbstub.c"

#elif defined (TARGET_PPC)

#if defined (TARGET_PPC64)

#define GDB_CORE_XML "power64-core.xml"

#else

#define GDB_CORE_XML "power-core.xml"

#endif

#include "target-ppc/gdbstub.c"

#elif defined (TARGET_SPARC)

#include "target-sparc/gdbstub.c"

#elif defined (TARGET_ARM)

#define GDB_CORE_XML "arm-core.xml"

#include "target-arm/gdbstub.c"

#elif defined (TARGET_M68K)

#define GDB_CORE_XML "cf-core.xml"

#include "target-m68k/gdbstub.c"

#elif defined (TARGET_MIPS)

#include "target-mips/gdbstub.c"

#elif defined(TARGET_OPENRISC)

#include "target-openrisc/gdbstub.c"

#elif defined (TARGET_SH4)

#include "target-sh4/gdbstub.c"

#elif defined (TARGET_MICROBLAZE)

#include "target-microblaze/gdbstub.c"

#elif defined (TARGET_CRIS)

#include "target-cris/gdbstub.c"

#elif defined (TARGET_ALPHA)

#include "target-alpha/gdbstub.c"

#elif defined (TARGET_S390X)

#include "target-s390x/gdbstub.c"

#elif defined (TARGET_LM32)

#include "target-lm32/gdbstub.c"

#elif defined(TARGET_XTENSA)

#include "target-xtensa/gdbstub.c"

#else

static int cpu_gdb_read_register(CPUArchState *env, uint8_t *mem_buf, int n)

{

    return 0;

}

static int cpu_gdb_write_register(CPUArchState *env, uint8_t *mem_buf, int n)

{

    return 0;

}

#endif

#ifdef GDB_CORE_XML

/* Encode data using the encoding for 'x' packets.  */

static int memtox(char *buf, const char *mem, int len)

{

    char *p = buf;

    char c;

    while (len--) {

        c = *(mem++);

        switch (c) {

        case '#': case '$': case '*': case '}':

            *(p++) = '}';

            *(p++) = c ^ 0x20;

            break;

        default:

            *(p++) = c;

            break;

        }

    }

    return p - buf;

}

static const char *get_feature_xml(const char *p, const char **newp)

{

    size_t len;

    int i;

    const char *name;

    static char target_xml[1024];

    len = 0;

    while (p[len] && p[len] != ':')

        len++;

    *newp = p + len;

    name = NULL;

    if (strncmp(p, "target.xml", len) == 0) {

        /* Generate the XML description for this CPU.  */

        if (!target_xml[0]) {

            GDBRegisterState *r;

            CPUState *cpu = first_cpu;

            snprintf(target_xml, sizeof(target_xml),

                     "<?xml version=\"1.0\"?>"

                     "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"

                     "<target>"

                     "<xi:include href=\"%s\"/>",

                     GDB_CORE_XML);

            for (r = cpu->gdb_regs; r; r = r->next) {

                pstrcat(target_xml, sizeof(target_xml), "<xi:include href=\"");

                pstrcat(target_xml, sizeof(target_xml), r->xml);

                pstrcat(target_xml, sizeof(target_xml), "\"/>");

            }

            pstrcat(target_xml, sizeof(target_xml), "</target>");

        }

        return target_xml;

    }

    for (i = 0; ; i++) {

        name = xml_builtin[i][0];

        if (!name || (strncmp(name, p, len) == 0 && strlen(name) == len))

            break;

    }

    return name ? xml_builtin[i][1] : NULL;

}

#endif

static int gdb_read_register(CPUState *cpu, uint8_t *mem_buf, int reg)

{

    CPUClass *cc = CPU_GET_CLASS(cpu);

    CPUArchState *env = cpu->env_ptr;

    GDBRegisterState *r;

    if (reg < cc->gdb_num_core_regs) {

        return cpu_gdb_read_register(env, mem_buf, reg);

    }

    for (r = cpu->gdb_regs; r; r = r->next) {

        if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) {

            return r->get_reg(env, mem_buf, reg - r->base_reg);

        }

    }

    return 0;

}

static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg)

{

    CPUClass *cc = CPU_GET_CLASS(cpu);

    CPUArchState *env = cpu->env_ptr;

    GDBRegisterState *r;

    if (reg < cc->gdb_num_core_regs) {

        return cpu_gdb_write_register(env, mem_buf, reg);

    }

    for (r = cpu->gdb_regs; r; r = r->next) {

        if (r->base_reg <= reg && reg < r->base_reg + r->num_regs) {

            return r->set_reg(env, mem_buf, reg - r->base_reg);

        }

    }

    return 0;

}

/* Register a supplemental set of CPU registers.  If g_pos is nonzero it

   specifies the first register number and these registers are included in

   a standard "g" packet.  Direction is relative to gdb, i.e. get_reg is

   gdb reading a CPU register, and set_reg is gdb modifying a CPU register.

 */

void gdb_register_coprocessor(CPUState *cpu,

                              gdb_reg_cb get_reg, gdb_reg_cb set_reg,

                              int num_regs, const char *xml, int g_pos)

{

    GDBRegisterState *s;

    GDBRegisterState **p;

    p = &cpu->gdb_regs;

    while (*p) {

        /* Check for duplicates.  */

        if (strcmp((*p)->xml, xml) == 0)

            return;

        p = &(*p)->next;

    }

    s = g_new0(GDBRegisterState, 1);

    s->base_reg = cpu->gdb_num_regs;

    s->num_regs = num_regs;

    s->get_reg = get_reg;

    s->set_reg = set_reg;

    s->xml = xml;

    /* Add to end of list.  */

    cpu->gdb_num_regs += num_regs;

    *p = s;

    if (g_pos) {

        if (g_pos != s->base_reg) {

            fprintf(stderr, "Error: Bad gdb register numbering for '%s'\n"

                    "Expected %d got %d\n", xml, g_pos, s->base_reg);

        }

    }

}

#ifndef CONFIG_USER_ONLY

static const int xlat_gdb_type[] = {

    [GDB_WATCHPOINT_WRITE]  = BP_GDB | BP_MEM_WRITE,

    [GDB_WATCHPOINT_READ]   = BP_GDB | BP_MEM_READ,

    [GDB_WATCHPOINT_ACCESS] = BP_GDB | BP_MEM_ACCESS,

};

#endif

static int gdb_breakpoint_insert(target_ulong addr, target_ulong len, int type)

{

    CPUState *cpu;

    CPUArchState *env;

    int err = 0;

    if (kvm_enabled()) {

        return kvm_insert_breakpoint(gdbserver_state->c_cpu, addr, len, type);

    }

    switch (type) {

    case GDB_BREAKPOINT_SW:

    case GDB_BREAKPOINT_HW:

        for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {

            env = cpu->env_ptr;

            err = cpu_breakpoint_insert(env, addr, BP_GDB, NULL);

            if (err)

                break;

        }

        return err;

#ifndef CONFIG_USER_ONLY

    case GDB_WATCHPOINT_WRITE:

    case GDB_WATCHPOINT_READ:

    case GDB_WATCHPOINT_ACCESS:

        for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {

            env = cpu->env_ptr;

            err = cpu_watchpoint_insert(env, addr, len, xlat_gdb_type[type],

                                        NULL);

            if (err)

                break;

        }

        return err;

#endif

    default:

        return -ENOSYS;

    }

}

static int gdb_breakpoint_remove(target_ulong addr, target_ulong len, int type)

{

    CPUState *cpu;

    CPUArchState *env;

    int err = 0;

    if (kvm_enabled()) {

        return kvm_remove_breakpoint(gdbserver_state->c_cpu, addr, len, type);

    }

    switch (type) {

    case GDB_BREAKPOINT_SW:

    case GDB_BREAKPOINT_HW:

        for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {

            env = cpu->env_ptr;

            err = cpu_breakpoint_remove(env, addr, BP_GDB);

            if (err)

                break;

        }

        return err;

#ifndef CONFIG_USER_ONLY

    case GDB_WATCHPOINT_WRITE:

    case GDB_WATCHPOINT_READ:

    case GDB_WATCHPOINT_ACCESS:

        for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {

            env = cpu->env_ptr;

            err = cpu_watchpoint_remove(env, addr, len, xlat_gdb_type[type]);

            if (err)

                break;

        }

        return err;

#endif

    default:

        return -ENOSYS;

    }

}

static void gdb_breakpoint_remove_all(void)

{

    CPUState *cpu;

    CPUArchState *env;

    if (kvm_enabled()) {

        kvm_remove_all_breakpoints(gdbserver_state->c_cpu);

        return;

    }

    for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {

        env = cpu->env_ptr;

        cpu_breakpoint_remove_all(env, BP_GDB);

#ifndef CONFIG_USER_ONLY

        cpu_watchpoint_remove_all(env, BP_GDB);

#endif

    }

}

static void gdb_set_cpu_pc(GDBState *s, target_ulong pc)

{

    CPUState *cpu = s->c_cpu;

    CPUClass *cc = CPU_GET_CLASS(cpu);

    cpu_synchronize_state(cpu);

    if (cc->set_pc) {

        cc->set_pc(cpu, pc);

    }

}

static CPUState *find_cpu(uint32_t thread_id)

{

    CPUState *cpu;

    for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {

        if (cpu_index(cpu) == thread_id) {

            return cpu;

        }

    }

    return NULL;

}

static int gdb_handle_packet(GDBState *s, const char *line_buf)

{

    CPUState *cpu;

    const char *p;

    uint32_t thread;

    int ch, reg_size, type, res;

    char buf[MAX_PACKET_LENGTH];

    uint8_t mem_buf[MAX_PACKET_LENGTH];

    uint8_t *registers;

    target_ulong addr, len;

#ifdef DEBUG_GDB

    printf("command='%s'\n", line_buf);

#endif

    p = line_buf;

    ch = *p++;

    switch(ch) {

    case '?':

        /* TODO: Make this return the correct value for user-mode.  */

        snprintf(buf, sizeof(buf), "T%02xthread:%02x;", GDB_SIGNAL_TRAP,

                 cpu_index(s->c_cpu));

        put_packet(s, buf);

        /* Remove all the breakpoints when this query is issued,

         * because gdb is doing and initial connect and the state

         * should be cleaned up.

         */

        gdb_breakpoint_remove_all();

        break;

    case 'c':

        if (*p != '\0') {

            addr = strtoull(p, (char **)&p, 16);

            gdb_set_cpu_pc(s, addr);

        }

        s->signal = 0;

        gdb_continue(s);

        return RS_IDLE;

    case 'C':

        s->signal = gdb_signal_to_target (strtoul(p, (char **)&p, 16));

        if (s->signal == -1)

            s->signal = 0;

        gdb_continue(s);

        return RS_IDLE;

    case 'v':

        if (strncmp(p, "Cont", 4) == 0) {

            int res_signal, res_thread;

            p += 4;

            if (*p == '?') {

                put_packet(s, "vCont;c;C;s;S");

                break;

            }

            res = 0;

            res_signal = 0;

            res_thread = 0;

            while (*p) {

                int action, signal;

                if (*p++ != ';') {

                    res = 0;

                    break;

                }

                action = *p++;

                signal = 0;

                if (action == 'C' || action == 'S') {

                    signal = strtoul(p, (char **)&p, 16);

                } else if (action != 'c' && action != 's') {

                    res = 0;

                    break;

                }

                thread = 0;

                if (*p == ':') {

                    thread = strtoull(p+1, (char **)&p, 16);

                }

                action = tolower(action);

                if (res == 0 || (res == 'c' && action == 's')) {

                    res = action;

                    res_signal = signal;

                    res_thread = thread;

                }

            }

            if (res) {

                if (res_thread != -1 && res_thread != 0) {

                    cpu = find_cpu(res_thread);

                    if (cpu == NULL) {

                        put_packet(s, "E22");

                        break;

                    }

                    s->c_cpu = cpu;

                }

                if (res == 's') {

                    cpu_single_step(s->c_cpu, sstep_flags);

                }

                s->signal = res_signal;

                gdb_continue(s);

                return RS_IDLE;

            }

            break;

        } else {

            goto unknown_command;

        }

    case 'k':

#ifdef CONFIG_USER_ONLY

        /* Kill the target */

        fprintf(stderr, "\nQEMU: Terminated via GDBstub\n");

        exit(0);

#endif

    case 'D':

        /* Detach packet */

        gdb_breakpoint_remove_all();

        gdb_syscall_mode = GDB_SYS_DISABLED;

        gdb_continue(s);

        put_packet(s, "OK");

        break;

    case 's':

        if (*p != '\0') {

            addr = strtoull(p, (char **)&p, 16);

            gdb_set_cpu_pc(s, addr);

        }

        cpu_single_step(s->c_cpu, sstep_flags);

        gdb_continue(s);

        return RS_IDLE;

    case 'F':

        {

            target_ulong ret;

            target_ulong err;

            ret = strtoull(p, (char **)&p, 16);

            if (*p == ',') {

                p++;

                err = strtoull(p, (char **)&p, 16);

            } else {

                err = 0;

            }

            if (*p == ',')

                p++;

            type = *p;

            if (s->current_syscall_cb) {

                s->current_syscall_cb(s->c_cpu, ret, err);

                s->current_syscall_cb = NULL;

            }

            if (type == 'C') {

                put_packet(s, "T02");

            } else {

                gdb_continue(s);

            }

        }

        break;

    case 'g':

        cpu_synchronize_state(s->g_cpu);

        len = 0;

        for (addr = 0; addr < s->g_cpu->gdb_num_regs; addr++) {

            reg_size = gdb_read_register(s->g_cpu, mem_buf + len, addr);

            len += reg_size;

        }

        memtohex(buf, mem_buf, len);

        put_packet(s, buf);

        break;

    case 'G':

        cpu_synchronize_state(s->g_cpu);

        registers = mem_buf;

        len = strlen(p) / 2;

        hextomem((uint8_t *)registers, p, len);

        for (addr = 0; addr < s->g_cpu->gdb_num_regs && len > 0; addr++) {

            reg_size = gdb_write_register(s->g_cpu, registers, addr);

            len -= reg_size;

            registers += reg_size;

        }

        put_packet(s, "OK");

        break;

    case 'm':

        addr = strtoull(p, (char **)&p, 16);

        if (*p == ',')

            p++;

        len = strtoull(p, NULL, 16);

        if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len, false) != 0) {

            put_packet (s, "E14");

        } else {

            memtohex(buf, mem_buf, len);

            put_packet(s, buf);

        }

        break;

    case 'M':

        addr = strtoull(p, (char **)&p, 16);

        if (*p == ',')

            p++;

        len = strtoull(p, (char **)&p, 16);

        if (*p == ':')

            p++;

        hextomem(mem_buf, p, len);

        if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len,

                                   true) != 0) {

            put_packet(s, "E14");

        } else {

            put_packet(s, "OK");

        }

        break;

    case 'p':

        /* Older gdb are really dumb, and don't use 'g' if 'p' is avaialable.

           This works, but can be very slow.  Anything new enough to

           understand XML also knows how to use this properly.  */

        if (!gdb_has_xml)

            goto unknown_command;

        addr = strtoull(p, (char **)&p, 16);

        reg_size = gdb_read_register(s->g_cpu, mem_buf, addr);

        if (reg_size) {

            memtohex(buf, mem_buf, reg_size);

            put_packet(s, buf);

        } else {

            put_packet(s, "E14");

        }

        break;

    case 'P':

        if (!gdb_has_xml)

            goto unknown_command;

        addr = strtoull(p, (char **)&p, 16);

        if (*p == '=')

            p++;

        reg_size = strlen(p) / 2;

        hextomem(mem_buf, p, reg_size);

        gdb_write_register(s->g_cpu, mem_buf, addr);

        put_packet(s, "OK");

        break;

    case 'Z':

    case 'z':

        type = strtoul(p, (char **)&p, 16);

        if (*p == ',')

            p++;

        addr = strtoull(p, (char **)&p, 16);

        if (*p == ',')

            p++;

        len = strtoull(p, (char **)&p, 16);

        if (ch == 'Z')

            res = gdb_breakpoint_insert(addr, len, type);

        else

            res = gdb_breakpoint_remove(addr, len, type);

        if (res >= 0)

             put_packet(s, "OK");

        else if (res == -ENOSYS)

            put_packet(s, "");

        else

            put_packet(s, "E22");

        break;

    case 'H':

        type = *p++;

        thread = strtoull(p, (char **)&p, 16);

        if (thread == -1 || thread == 0) {

            put_packet(s, "OK");

            break;

        }

        cpu = find_cpu(thread);

        if (cpu == NULL) {

            put_packet(s, "E22");

            break;

        }

        switch (type) {

        case 'c':

            s->c_cpu = cpu;

            put_packet(s, "OK");

            break;

        case 'g':

            s->g_cpu = cpu;

            put_packet(s, "OK");

            break;

        default:

             put_packet(s, "E22");

             break;

        }

        break;

    case 'T':

        thread = strtoull(p, (char **)&p, 16);

        cpu = find_cpu(thread);

        if (cpu != NULL) {

            put_packet(s, "OK");

        } else {

            put_packet(s, "E22");

        }

        break;

    case 'q':

    case 'Q':

        /* parse any 'q' packets here */

        if (!strcmp(p,"qemu.sstepbits")) {

            /* Query Breakpoint bit definitions */

            snprintf(buf, sizeof(buf), "ENABLE=%x,NOIRQ=%x,NOTIMER=%x",

                     SSTEP_ENABLE,

                     SSTEP_NOIRQ,

                     SSTEP_NOTIMER);

            put_packet(s, buf);

            break;

        } else if (strncmp(p,"qemu.sstep",10) == 0) {

            /* Display or change the sstep_flags */

            p += 10;

            if (*p != '=') {

                /* Display current setting */

                snprintf(buf, sizeof(buf), "0x%x", sstep_flags);

                put_packet(s, buf);

                break;

            }

            p++;

            type = strtoul(p, (char **)&p, 16);

            sstep_flags = type;

            put_packet(s, "OK");

            break;

        } else if (strcmp(p,"C") == 0) {

            /* "Current thread" remains vague in the spec, so always return

             *  the first CPU (gdb returns the first thread). */

            put_packet(s, "QC1");

            break;

        } else if (strcmp(p,"fThreadInfo") == 0) {

            s->query_cpu = first_cpu;

            goto report_cpuinfo;

        } else if (strcmp(p,"sThreadInfo") == 0) {

        report_cpuinfo:

            if (s->query_cpu) {

                snprintf(buf, sizeof(buf), "m%x", cpu_index(s->query_cpu));

                put_packet(s, buf);

                s->query_cpu = s->query_cpu->next_cpu;

            } else

                put_packet(s, "l");

            break;

        } else if (strncmp(p,"ThreadExtraInfo,", 16) == 0) {

            thread = strtoull(p+16, (char **)&p, 16);

            cpu = find_cpu(thread);

            if (cpu != NULL) {

                cpu_synchronize_state(cpu);

                len = snprintf((char *)mem_buf, sizeof(mem_buf),

                               "CPU#%d [%s]", cpu->cpu_index,

                               cpu->halted ? "halted " : "running");

                memtohex(buf, mem_buf, len);

                put_packet(s, buf);

            }

            break;

        }

#ifdef CONFIG_USER_ONLY

        else if (strncmp(p, "Offsets", 7) == 0) {

            CPUArchState *env = s->c_cpu->env_ptr;

            TaskState *ts = env->opaque;

            snprintf(buf, sizeof(buf),

                     "Text=" TARGET_ABI_FMT_lx ";Data=" TARGET_ABI_FMT_lx

                     ";Bss=" TARGET_ABI_FMT_lx,

                     ts->info->code_offset,

                     ts->info->data_offset,

                     ts->info->data_offset);

            put_packet(s, buf);

            break;

        }

#else /* !CONFIG_USER_ONLY */

        else if (strncmp(p, "Rcmd,", 5) == 0) {

            int len = strlen(p + 5);

            if ((len % 2) != 0) {

                put_packet(s, "E01");

                break;

            }

            hextomem(mem_buf, p + 5, len);

            len = len / 2;

            mem_buf[len++] = 0;

            qemu_chr_be_write(s->mon_chr, mem_buf, len);

            put_packet(s, "OK");

            break;

        }

#endif /* !CONFIG_USER_ONLY */

        if (strncmp(p, "Supported", 9) == 0) {

            snprintf(buf, sizeof(buf), "PacketSize=%x", MAX_PACKET_LENGTH);

#ifdef GDB_CORE_XML

            pstrcat(buf, sizeof(buf), ";qXfer:features:read+");

#endif

            put_packet(s, buf);

            break;

        }

#ifdef GDB_CORE_XML

        if (strncmp(p, "Xfer:features:read:", 19) == 0) {

            const char *xml;

            target_ulong total_len;

            gdb_has_xml = 1;

            p += 19;

            xml = get_feature_xml(p, &p);

            if (!xml) {

                snprintf(buf, sizeof(buf), "E00");

                put_packet(s, buf);

                break;

            }

            if (*p == ':')

                p++;

            addr = strtoul(p, (char **)&p, 16);

            if (*p == ',')

                p++;

            len = strtoul(p, (char **)&p, 16);

            total_len = strlen(xml);

            if (addr > total_len) {

                snprintf(buf, sizeof(buf), "E00");

                put_packet(s, buf);

                break;

            }

            if (len > (MAX_PACKET_LENGTH - 5) / 2)

                len = (MAX_PACKET_LENGTH - 5) / 2;

            if (len < total_len - addr) {

                buf[0] = 'm';

                len = memtox(buf + 1, xml + addr, len);

            } else {

                buf[0] = 'l';

                len = memtox(buf + 1, xml + addr, total_len - addr);

            }

            put_packet_binary(s, buf, len + 1);

            break;

        }

#endif

        /* Unrecognised 'q' command.  */

        goto unknown_command;

    default:

    unknown_command:

        /* put empty packet */

        buf[0] = '\0';

        put_packet(s, buf);

        break;

    }

    return RS_IDLE;

}

void gdb_set_stop_cpu(CPUState *cpu)

{

    gdbserver_state->c_cpu = cpu;

    gdbserver_state->g_cpu = cpu;

}

#ifndef CONFIG_USER_ONLY

static void gdb_vm_state_change(void *opaque, int running, RunState state)

{

    GDBState *s = gdbserver_state;

    CPUArchState *env = s->c_cpu->env_ptr;

    CPUState *cpu = s->c_cpu;

    char buf[256];

    const char *type;

    int ret;

    if (running || s->state == RS_INACTIVE) {

        return;

    }

    /* Is there a GDB syscall waiting to be sent?  */

    if (s->current_syscall_cb) {

        put_packet(s, s->syscall_buf);

        return;

    }

    switch (state) {

    case RUN_STATE_DEBUG:

        if (env->watchpoint_hit) {

            switch (env->watchpoint_hit->flags & BP_MEM_ACCESS) {

            case BP_MEM_READ:

                type = "r";

                break;

            case BP_MEM_ACCESS:

                type = "a";

                break;

            default:

                type = "";

                break;

            }

            snprintf(buf, sizeof(buf),

                     "T%02xthread:%02x;%swatch:" TARGET_FMT_lx ";",

                     GDB_SIGNAL_TRAP, cpu_index(cpu), type,

                     env->watchpoint_hit->vaddr);

            env->watchpoint_hit = NULL;