Bochs/bochs/gdbstub.cc
2002-10-03 05:29:15 +00:00

791 lines
19 KiB
C++

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <signal.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <ctype.h>
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#include "gdbstub.h"
#define LOG_THIS genlog->
#define IFDBG(x) x
static int last_stop_reason = GDBSTUB_STOP_NO_REASON;
#define GDBSTUB_EXECUTION_BREAKPOINT (0xac1)
#define GDBSTUB_TRACE (0xac2)
#define GDBSTUB_USER_BREAK (0xac3)
static int listen_socket_fd;
static int socket_fd;
#if defined(__CYGWIN__)
/*
* Check whether "cp" is a valid ascii representation
* of an Internet address and convert to a binary address.
* Returns 1 if the address is valid, 0 if not.
* This replaces inet_addr, the return value from which
* cannot distinguish between failure and a local broadcast address.
*/
int inet_aton(const char *cp, struct in_addr * addr)
{
unsigned int val;
int base,n;
char c;
u_int parts[4];
u_int *pp = parts;
for (;;)
{
/*
* Collect number up to `.''. Values are specified as for C:
* 0x=hex, 0=octal, other=decimal.
*/
val = 0;
base = 10;
if (*cp == '0')
{
if (*++cp == 'x' || *cp == 'X')
base = 16, cp++;
else
base = 8;
}
while ((c = *cp) != '\0')
{
if (isascii(c) && isdigit(c))
{
val = (val * base) + (c - '0');
cp++;
continue;
}
if (base == 16 && isascii(c) && isxdigit(c))
{
val = (val << 4) +
(c + 10 - (islower(c) ? 'a' : 'A'));
cp++;
continue;
}
break;
}
if (*cp == '.')
{
/*
* Internet format: a.b.c.d a.b.c (with c treated as
* 16-bits) a.b (with b treated as 24 bits)
*/
if (pp >= parts + 3 || val > 0xff)
return (0);
*pp++ = val, cp++;
}
else
break;
}
/*
* Check for trailing characters.
*/
if (*cp && (!isascii(*cp) || !isspace(*cp)))
return (0);
/*
* Concoct the address according to the number of parts specified.
*/
n = pp - parts + 1;
switch (n)
{
case 1: /* a -- 32 bits */
break;
case 2: /* a.b -- 8.24 bits */
if (val > 0xffffff)
return (0);
val |= parts[0] << 24;
break;
case 3: /* a.b.c -- 8.8.16 bits */
if (val > 0xffff)
return (0);
val |= (parts[0] << 24) | (parts[1] << 16);
break;
case 4: /* a.b.c.d -- 8.8.8.8 bits */
if (val > 0xff)
return (0);
val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
break;
}
if (addr)
addr->s_addr = htonl(val);
return (1);
}
#endif
static int hex(char ch)
{
if ((ch >= 'a') && (ch <= 'f')) return(ch - 'a' + 10);
if ((ch >= '0') && (ch <= '9')) return(ch - '0');
if ((ch >= 'A') && (ch <= 'F')) return(ch - 'A' + 10);
return(-1);
}
static void put_debug_char(char ch)
{
send(socket_fd, &ch, 1, 0);
}
static char get_debug_char(void)
{
char ch;
recv(socket_fd, &ch, 1, 0);
return(ch);
}
static const char hexchars[]="0123456789abcdef";
static void put_reply(char* buffer)
{
unsigned char csum;
int i;
BX_INFO (("put_buffer %s", buffer));
do
{
put_debug_char('$');
csum = 0;
i = 0;
while (buffer[i] != 0)
{
put_debug_char(buffer[i]);
csum = csum + buffer[i];
i++;
}
put_debug_char('#');
put_debug_char(hexchars[csum >> 4]);
put_debug_char(hexchars[csum % 16]);
} while (get_debug_char() != '+');
}
static void get_command(char* buffer)
{
unsigned char checksum;
unsigned char xmitcsum;
char ch;
unsigned int count;
unsigned int i;
do
{
while ((ch = get_debug_char()) != '$');
checksum = 0;
xmitcsum = 0;
count = 0;
while (1)
{
ch = get_debug_char();
if (ch == '#') break;
checksum = checksum + ch;
buffer[count] = ch;
count++;
}
buffer[count] = 0;
if (ch == '#')
{
xmitcsum = hex(get_debug_char()) << 4;
xmitcsum += hex(get_debug_char());
if (checksum != xmitcsum)
{
BX_INFO (("Bad checksum"));
}
}
if (checksum != xmitcsum)
{
put_debug_char('-');
}
else
{
put_debug_char('+');
if (buffer[2] == ':')
{
put_debug_char(buffer[0]);
put_debug_char(buffer[1]);
count = strlen(buffer);
for (i = 3; i <= count; i++)
{
buffer[i - 3] = buffer[i];
}
}
}
} while (checksum != xmitcsum);
}
void hex2mem(char* buf, unsigned char* mem, int count)
{
int i;
unsigned char ch;
for (i = 0; i<count; i++)
{
ch = hex(*buf++) << 4;
ch = ch + hex(*buf++);
*mem = ch;
mem++;
}
}
char* mem2hex(char* mem, char* buf, int count)
{
int i;
unsigned char ch;
for (i = 0; i<count; i++)
{
ch = *mem;
mem++;
*buf = hexchars[ch >> 4];
buf++;
*buf = hexchars[ch % 16];
buf++;
}
*buf = 0;
return(buf);
}
static int continue_thread = -1;
static int other_thread = 0;
#define NUMREGS (16)
#define NUMREGSBYTES (NUMREGS * 4)
static int registers[NUMREGS];
#define MAX_BREAKPOINTS (255)
static int breakpoints[MAX_BREAKPOINTS] = {0,};
static int nr_breakpoints = 0;
static int stub_trace_flag = 0;
static int instr_count = 0;
static int saved_eip = 0;
int bx_gdbstub_check(unsigned int eip)
{
unsigned int i;
unsigned char ch;
long arg;
int r;
fd_set fds;
struct timeval tv = {0, 0};
instr_count++;
if ((instr_count % 500) == 0)
{
#ifndef __CYGWIN__
arg = fcntl(socket_fd, F_GETFL);
fcntl(socket_fd, F_SETFL, arg | O_NONBLOCK);
r = recv(socket_fd, &ch, 1, 0);
fcntl(socket_fd, F_SETFL, arg);
#else
FD_ZERO(&fds);
FD_SET(socket_fd, &fds);
r = select(socket_fd + 1, &fds, NULL, NULL, &tv);
if (r == 1)
{
r = recv(socket_fd, &ch, 1, 0);
}
#endif
if (r == 1)
{
BX_INFO (("Got byte %x", (unsigned int)ch));
last_stop_reason = GDBSTUB_USER_BREAK;
return(GDBSTUB_USER_BREAK);
}
}
if (stub_trace_flag == 1)
{
last_stop_reason = GDBSTUB_TRACE;
return(GDBSTUB_TRACE);
}
for (i = 0; i < nr_breakpoints; i++)
{
if (eip == breakpoints[i])
{
BX_INFO (("found breakpoint at %x", eip));
last_stop_reason = GDBSTUB_EXECUTION_BREAKPOINT;
return(GDBSTUB_EXECUTION_BREAKPOINT);
}
}
last_stop_reason = GDBSTUB_STOP_NO_REASON;
return(GDBSTUB_STOP_NO_REASON);
}
static int remove_breakpoint(int addr, int len)
{
unsigned int i;
if (len != 1)
{
return(0);
}
for (i = 0; i < MAX_BREAKPOINTS; i++)
{
if (breakpoints[i] == addr)
{
BX_INFO (("Removing breakpoint at %x", addr));
breakpoints[i] = 0;
return(1);
}
}
return(0);
}
static void insert_breakpoint(int addr)
{
unsigned int i;
BX_INFO (("setting breakpoint at %x", addr));
for (i = 0; i < MAX_BREAKPOINTS; i++)
{
if (breakpoints[i] == 0)
{
breakpoints[i] = addr;
if (i >= nr_breakpoints)
{
nr_breakpoints = i + 1;
}
return;
}
}
BX_INFO (("No slot for breakpoint"));
}
static void write_signal(char* buf, int signal)
{
buf[0] = hexchars[signal >> 4];
buf[1] = hexchars[signal % 16];
buf[2] = 0;
}
static int access_linear(Bit32u laddress,
unsigned len,
unsigned int rw,
Bit8u* data)
{
Bit32u phys;
Boolean valid;
if (((laddress & 0xfff) + len) > 4096)
{
valid = access_linear(laddress,
4096 - (laddress & 0xfff),
rw,
data);
if (!valid)
{
return(valid);
}
valid = access_linear(laddress,
len + (laddress & 0xfff) - 4096,
rw,
(Bit8u *)((unsigned int)data +
(laddress & 0xfff)));
return(valid);
}
BX_CPU_THIS_PTR dbg_xlate_linear2phy((Bit32u)laddress,
(Bit32u*)&phys,
(Boolean*)&valid);
if (!valid)
{
return(0);
}
if (rw == BX_READ)
{
valid = bx_mem.dbg_fetch_mem(phys, len, data);
}
else
{
valid = bx_mem.dbg_set_mem(phys, len, data);
}
return(valid);
}
static void debug_loop(void)
{
char buffer[255];
char obuf[255];
int ne;
unsigned char mem[255];
ne = 0;
while (ne == 0)
{
get_command(buffer);
BX_INFO (("get_buffer %s", buffer));
switch (buffer[0])
{
case 'c':
{
char buf[255];
int new_eip;
if (buffer[1] != 0)
{
new_eip = atoi(buffer + 1);
BX_INFO (("continuing at %x", new_eip));
bx_cpu.invalidate_prefetch_q();
saved_eip = EIP;
BX_CPU_THIS_PTR dword.eip = new_eip;
}
stub_trace_flag = 0;
bx_cpu.cpu_loop(-1);
BX_VGA_THIS timer();
if (buffer[1] != 0)
{
bx_cpu.invalidate_prefetch_q();
BX_CPU_THIS_PTR dword.eip = saved_eip;
}
BX_INFO (("stopped with %x", last_stop_reason));
buf[0] = 'S';
if (last_stop_reason == GDBSTUB_EXECUTION_BREAKPOINT ||
last_stop_reason == GDBSTUB_TRACE)
{
write_signal(&buf[1], SIGTRAP);
}
else
{
write_signal(&buf[1], 0);
}
put_reply(buf);
break;
}
case 's':
{
char buf[255];
stub_trace_flag = 1;
bx_cpu.cpu_loop(-1);
BX_VGA_THIS timer();
stub_trace_flag = 0;
BX_INFO (("stopped with %x", last_stop_reason));
buf[0] = 'S';
if (last_stop_reason == GDBSTUB_EXECUTION_BREAKPOINT ||
last_stop_reason == GDBSTUB_TRACE)
{
write_signal(&buf[1], SIGTRAP);
}
else
{
write_signal(&buf[1], SIGTRAP);
}
put_reply(buf);
break;
}
case 'M':
{
int addr;
int len;
unsigned char mem[255];
char* ebuf;
addr = strtoul(&buffer[1], &ebuf, 16);
len = strtoul(ebuf + 1, &ebuf, 16);
hex2mem(ebuf + 1, mem, len);
if (len == 1 && mem[0] == 0xcc)
{
insert_breakpoint(addr);
put_reply("OK");
}
else if (remove_breakpoint(addr, len))
{
put_reply("OK");
}
else
{
if (access_linear(addr,
len,
BX_WRITE,
mem))
{
put_reply("OK");
}
else
{
put_reply("ENN");
}
}
break;
}
case 'm':
{
int addr;
int len;
char* ebuf;
addr = strtoul(&buffer[1], &ebuf, 16);
len = strtoul(ebuf + 1, NULL, 16);
BX_INFO (("addr %x len %x", addr, len));
access_linear(addr,
len,
BX_READ,
mem);
mem2hex((char *)mem, obuf, len);
put_reply(obuf);
break;
}
case 'P':
{
int reg;
int value;
char* ebuf;
reg = strtoul(&buffer[1], &ebuf, 16);
value = ntohl(strtoul(ebuf + 1, &ebuf, 16));
BX_INFO (("reg %d set to %x", reg, value));
switch (reg)
{
case 1:
EAX = value;
break;
case 2:
ECX = value;
break;
case 3:
EBX = value;
break;
case 4:
ESP = value;
break;
case 5:
EBP = value;
break;
case 6:
ESI = value;
break;
case 7:
EDI = value;
break;
case 8:
EIP = value;
BX_CPU_THIS_PTR invalidate_prefetch_q();
break;
default:
break;
}
put_reply("OK");
break;
}
case 'g':
registers[0] = EAX;
registers[1] = ECX;
registers[2] = EDX;
registers[3] = EBX;
registers[4] = ESP;
registers[5] = EBP;
registers[6] = ESI;
registers[7] = EDI;
if (last_stop_reason == GDBSTUB_EXECUTION_BREAKPOINT)
{
registers[8] = EIP + 1;
}
else
{
registers[8] = EIP;
}
registers[9] = BX_CPU_THIS_PTR read_eflags();
registers[10] =
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value;
registers[11] =
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value;
registers[12] =
BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS].selector.value;
registers[13] =
BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES].selector.value;
registers[14] =
BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS].selector.value;
registers[15] =
BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS].selector.value;
mem2hex((char *)registers, obuf, NUMREGSBYTES);
put_reply(obuf);
break;
case '?':
sprintf(obuf, "S%02x", SIGTRAP);
put_reply(obuf);
break;
case 'H':
if (buffer[1] == 'c')
{
continue_thread = strtol(&buffer[2], NULL, 16);
put_reply("OK");
}
else if (buffer[1] == 'g')
{
other_thread = strtol(&buffer[2], NULL, 16);
put_reply("OK");
}
else
{
put_reply("ENN");
}
break;
case 'q':
if (buffer[1] == 'C')
{
sprintf(obuf,"%Lx", 1);
put_reply(obuf);
}
else if (strncmp(&buffer[1], "Offsets", strlen("Offsets")) ==
0)
{
sprintf(obuf,
"Text=%x;Data=%x;Bss=%x",
bx_options.gdbstub.text_base,
bx_options.gdbstub.data_base,
bx_options.gdbstub.bss_base);
put_reply(obuf);
}
else
{
put_reply("ENN");
}
break;
case 'k':
BX_PANIC (("Debugger asked us to quit\n"));
break;
default:
put_reply("");
break;
}
}
}
static void wait_for_connect(int portn)
{
struct sockaddr_in sockaddr;
struct sockaddr csockaddr;
signed int csockaddr_len;
int r;
int opt;
listen_socket_fd = socket(PF_INET, SOCK_STREAM, 0);
if (listen_socket_fd == -1)
{
BX_PANIC (("Failed to create socket\n"));
exit(1);
}
sockaddr.sin_family = AF_INET;
sockaddr.sin_port = htons(portn);
inet_aton("127.0.0.1", &sockaddr.sin_addr);
r = bind(listen_socket_fd, (struct sockaddr *)&sockaddr,
sizeof(sockaddr));
if (r == -1)
{
BX_PANIC (("Failed to bind socket\n"));
}
opt = 1;
setsockopt(listen_socket_fd, SOL_SOCKET, SO_REUSEADDR, &opt,
sizeof(opt));
r = listen(listen_socket_fd, 0);
if (r == -1)
{
BX_PANIC (("Failed to listen on socket\n"));
}
csockaddr_len = sizeof csockaddr;
socket_fd = accept(listen_socket_fd, &csockaddr, (socklen_t *) &csockaddr_len);
if (socket_fd == -1)
{
BX_PANIC (("Failed to accept on socket\n"));
}
close(listen_socket_fd);
opt = 1;
setsockopt(socket_fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
}
void bx_gdbstub_init(int argc, char* argv[])
{
int portn;
/* Do bochs init */
// parse any remaining args in the usual way
bx_parse_cmdline (1, argc, argv);
portn = bx_options.gdbstub.port;
printf("Communicating with gdb on port %d\n", portn);
bx_init_hardware();
#if 1
/* Wait for connect */
wait_for_connect(portn);
/* Do debugger command loop */
debug_loop();
#endif
/* CPU loop */
bx_cpu.cpu_loop(-1);
}