/*
* gdb server stub
*
* Copyright (c) 2003 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <signal.h>
#include "config.h"
#include "cpu.h"
#include "thunk.h"
#include "exec-all.h"
//#define DEBUG_GDB
int gdbstub_fd = -1;
/* return 0 if OK */
static int gdbstub_open(int port)
{
struct sockaddr_in sockaddr;
socklen_t len;
int fd, val, ret;
fd = socket(PF_INET, SOCK_STREAM, 0);
if (fd < 0) {
perror("socket");
return -1;
}
/* allow fast reuse */
val = 1;
setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
sockaddr.sin_family = AF_INET;
sockaddr.sin_port = htons(port);
sockaddr.sin_addr.s_addr = 0;
ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr));
if (ret < 0) {
perror("bind");
return -1;
}
ret = listen(fd, 0);
if (ret < 0) {
perror("listen");
return -1;
}
/* now wait for one connection */
for(;;) {
len = sizeof(sockaddr);
gdbstub_fd = accept(fd, (struct sockaddr *)&sockaddr, &len);
if (gdbstub_fd < 0 && errno != EINTR) {
perror("accept");
return -1;
} else if (gdbstub_fd >= 0) {
break;
}
}
/* set short latency */
val = 1;
setsockopt(gdbstub_fd, SOL_TCP, TCP_NODELAY, &val, sizeof(val));
return 0;
}
static int get_char(void)
{
uint8_t ch;
int ret;
for(;;) {
ret = read(gdbstub_fd, &ch, 1);
if (ret < 0) {
if (errno != EINTR && errno != EAGAIN)
return -1;
} else if (ret == 0) {
return -1;
} else {
break;
}
}
return ch;
}
static void put_buffer(const uint8_t *buf, int len)
{
int ret;
while (len > 0) {
ret = write(gdbstub_fd, buf, len);
if (ret < 0) {
if (errno != EINTR && errno != EAGAIN)
return;
} else {
buf += ret;
len -= ret;
}
}
}
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 or EOF */
static int get_packet(char *buf, int buf_size)
{
int ch, len, csum, csum1;
char reply[1];
for(;;) {
for(;;) {
ch = get_char();
if (ch < 0)
return -1;
if (ch == '$')
break;
}
len = 0;
csum = 0;
for(;;) {
ch = get_char();
if (ch < 0)
return -1;
if (ch == '#')
break;
if (len > buf_size - 1)
return -1;
buf[len++] = ch;
csum += ch;
}
buf[len] = '\0';
ch = get_char();
if (ch < 0)
return -1;
csum1 = fromhex(ch) << 4;
ch = get_char();
if (ch < 0)
return -1;
csum1 |= fromhex(ch);
if ((csum & 0xff) != csum1) {
reply[0] = '-';
put_buffer(reply, 1);
} else {
reply[0] = '+';
put_buffer(reply, 1);
break;
}
}
#ifdef DEBUG_GDB
printf("command='%s'\n", buf);
#endif
return len;
}
/* return -1 if error, 0 if OK */
static int put_packet(char *buf)
{
char buf1[3];
int len, csum, ch, i;
#ifdef DEBUG_GDB
printf("reply='%s'\n", buf);
#endif
for(;;) {
buf1[0] = '$';
put_buffer(buf1, 1);
len = strlen(buf);
put_buffer(buf, len);
csum = 0;
for(i = 0; i < len; i++) {
csum += buf[i];
}
buf1[0] = '#';
buf1[1] = tohex((csum >> 4) & 0xf);
buf1[2] = tohex((csum) & 0xf);
put_buffer(buf1, 3);
ch = get_char();
if (ch < 0)
return -1;
if (ch == '+')
break;
}
return 0;
}
/* better than nothing for SOFTMMU : we use physical addresses */
#if !defined(CONFIG_USER_ONLY)
static int memory_rw(uint8_t *buf, uint32_t addr, int len, int is_write)
{
uint8_t *ptr;
if (addr >= phys_ram_size ||
((int64_t)addr + len > phys_ram_size))
return -1;
ptr = phys_ram_base + addr;
if (is_write)
memcpy(ptr, buf, len);
else
memcpy(buf, ptr, len);
return 0;
}
#else
static int memory_rw(uint8_t *buf, uint32_t addr, int len, int is_write)
{
int l, flags;
uint32_t page;
while (len > 0) {
page = addr & TARGET_PAGE_MASK;
l = (page + TARGET_PAGE_SIZE) - addr;
if (l > len)
l = len;
flags = page_get_flags(page);
if (!(flags & PAGE_VALID))
return -1;
if (is_write) {
if (!(flags & PAGE_WRITE))
return -1;
memcpy((uint8_t *)addr, buf, l);
} else {
if (!(flags & PAGE_READ))
return -1;
memcpy(buf, (uint8_t *)addr, l);
}
len -= l;
buf += l;
addr += l;
}
return 0;
}
#endif
#if defined(TARGET_I386)
static void to_le32(uint8_t *p, int v)
{
p[0] = v;
p[1] = v >> 8;
p[2] = v >> 16;
p[3] = v >> 24;
}
static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
{
int i, fpus;
for(i = 0; i < 8; i++) {
to_le32(mem_buf + i * 4, env->regs[i]);
}
to_le32(mem_buf + 8 * 4, env->eip);
to_le32(mem_buf + 9 * 4, env->eflags);
to_le32(mem_buf + 10 * 4, env->segs[R_CS].selector);
to_le32(mem_buf + 11 * 4, env->segs[R_SS].selector);
to_le32(mem_buf + 12 * 4, env->segs[R_DS].selector);
to_le32(mem_buf + 13 * 4, env->segs[R_ES].selector);
to_le32(mem_buf + 14 * 4, env->segs[R_FS].selector);
to_le32(mem_buf + 15 * 4, env->segs[R_GS].selector);
/* XXX: convert floats */
for(i = 0; i < 8; i++) {
memcpy(mem_buf + 16 * 4 + i * 10, &env->fpregs[i], 10);
}
to_le32(mem_buf + 36 * 4, env->fpuc);
fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
to_le32(mem_buf + 37 * 4, fpus);
to_le32(mem_buf + 38 * 4, 0); /* XXX: convert tags */
to_le32(mem_buf + 39 * 4, 0); /* fiseg */
to_le32(mem_buf + 40 * 4, 0); /* fioff */
to_le32(mem_buf + 41 * 4, 0); /* foseg */
to_le32(mem_buf + 42 * 4, 0); /* fooff */
to_le32(mem_buf + 43 * 4, 0); /* fop */
return 44 * 4;
}
static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
{
uint32_t *registers = (uint32_t *)mem_buf;
int i;
for(i = 0; i < 8; i++) {
env->regs[i] = tswapl(registers[i]);
}
env->eip = registers[8];
env->eflags = registers[9];
#if defined(CONFIG_USER_ONLY)
#define LOAD_SEG(index, sreg)\
if (tswapl(registers[index]) != env->segs[sreg].selector)\
cpu_x86_load_seg(env, sreg, tswapl(registers[index]));
LOAD_SEG(10, R_CS);
LOAD_SEG(11, R_SS);
LOAD_SEG(12, R_DS);
LOAD_SEG(13, R_ES);
LOAD_SEG(14, R_FS);
LOAD_SEG(15, R_GS);
#endif
}
#else
static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
{
return 0;
}
static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
{
}
#endif
/* port = 0 means default port */
int cpu_gdbstub(void *opaque, int (*main_loop)(void *opaque), int port)
{
CPUState *env;
const char *p;
int ret, ch, reg_size, type;
char buf[4096];
uint8_t mem_buf[2000];
uint32_t *registers;
uint32_t addr, len;
printf("Waiting gdb connection on port %d\n", port);
if (gdbstub_open(port) < 0)
return -1;
printf("Connected\n");
for(;;) {
ret = get_packet(buf, sizeof(buf));
if (ret < 0)
break;
p = buf;
ch = *p++;
switch(ch) {
case '?':
snprintf(buf, sizeof(buf), "S%02x", SIGTRAP);
put_packet(buf);
break;
case 'c':
if (*p != '\0') {
addr = strtoul(p, (char **)&p, 16);
env = cpu_gdbstub_get_env(opaque);
#if defined(TARGET_I386)
env->eip = addr;
#endif
}
ret = main_loop(opaque);
if (ret == EXCP_DEBUG)
ret = SIGTRAP;
else
ret = 0;
snprintf(buf, sizeof(buf), "S%02x", ret);
put_packet(buf);
break;
case 's':
env = cpu_gdbstub_get_env(opaque);
if (*p != '\0') {
addr = strtoul(p, (char **)&p, 16);
#if defined(TARGET_I386)
env->eip = addr;
#endif
}
cpu_single_step(env, 1);
ret = main_loop(opaque);
cpu_single_step(env, 0);
if (ret == EXCP_DEBUG)
ret = SIGTRAP;
else
ret = 0;
snprintf(buf, sizeof(buf), "S%02x", ret);
put_packet(buf);
break;
case 'g':
env = cpu_gdbstub_get_env(opaque);
reg_size = cpu_gdb_read_registers(env, mem_buf);
memtohex(buf, mem_buf, reg_size);
put_packet(buf);
break;
case 'G':
env = cpu_gdbstub_get_env(opaque);
registers = (void *)mem_buf;
len = strlen(p) / 2;
hextomem((uint8_t *)registers, p, len);
cpu_gdb_write_registers(env, mem_buf, len);
put_packet("OK");
break;
case 'm':
addr = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
len = strtoul(p, NULL, 16);
if (memory_rw(mem_buf, addr, len, 0) != 0)
memset(mem_buf, 0, len);
memtohex(buf, mem_buf, len);
put_packet(buf);
break;
case 'M':
addr = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
len = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
hextomem(mem_buf, p, len);
if (memory_rw(mem_buf, addr, len, 1) != 0)
put_packet("ENN");
else
put_packet("OK");
break;
case 'Z':
type = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
addr = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
len = strtoul(p, (char **)&p, 16);
if (type == 0 || type == 1) {
env = cpu_gdbstub_get_env(opaque);
if (cpu_breakpoint_insert(env, addr) < 0)
goto breakpoint_error;
put_packet("OK");
} else {
breakpoint_error:
put_packet("ENN");
}
break;
case 'z':
type = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
addr = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
len = strtoul(p, (char **)&p, 16);
if (type == 0 || type == 1) {
env = cpu_gdbstub_get_env(opaque);
cpu_breakpoint_remove(env, addr);
put_packet("OK");
} else {
goto breakpoint_error;
}
break;
case 'Q':
if (!strncmp(p, "Tinit", 5)) {
/* init traces */
put_packet("OK");
} else if (!strncmp(p, "TStart", 6)) {
/* start log (gdb 'tstart' command) */
env = cpu_gdbstub_get_env(opaque);
tb_flush(env);
cpu_set_log(CPU_LOG_ALL);
put_packet("OK");
} else if (!strncmp(p, "TStop", 5)) {
/* stop log (gdb 'tstop' command) */
cpu_set_log(0);
put_packet("OK");
} else {
goto unknown_command;
}
break;
default:
unknown_command:
/* put empty packet */
buf[0] = '\0';
put_packet(buf);
break;
}
}
return 0;
}
