binutils-gdb/gdb/gdbserver/server.c

623 lines
14 KiB
C

/* Main code for remote server for GDB.
Copyright 1989, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2002, 2003, 2004,
2005
Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "server.h"
#include <unistd.h>
#include <signal.h>
#include <sys/wait.h>
unsigned long cont_thread;
unsigned long general_thread;
unsigned long step_thread;
unsigned long thread_from_wait;
unsigned long old_thread_from_wait;
int extended_protocol;
int server_waiting;
jmp_buf toplevel;
/* The PID of the originally created or attached inferior. Used to
send signals to the process when GDB sends us an asynchronous interrupt
(user hitting Control-C in the client), and to wait for the child to exit
when no longer debugging it. */
unsigned long signal_pid;
static unsigned char
start_inferior (char *argv[], char *statusptr)
{
signal (SIGTTOU, SIG_DFL);
signal (SIGTTIN, SIG_DFL);
signal_pid = create_inferior (argv[0], argv);
fprintf (stderr, "Process %s created; pid = %ld\n", argv[0],
signal_pid);
signal (SIGTTOU, SIG_IGN);
signal (SIGTTIN, SIG_IGN);
tcsetpgrp (fileno (stderr), signal_pid);
/* Wait till we are at 1st instruction in program, return signal number. */
return mywait (statusptr, 0);
}
static int
attach_inferior (int pid, char *statusptr, unsigned char *sigptr)
{
/* myattach should return -1 if attaching is unsupported,
0 if it succeeded, and call error() otherwise. */
if (myattach (pid) != 0)
return -1;
fprintf (stderr, "Attached; pid = %d\n", pid);
/* FIXME - It may be that we should get the SIGNAL_PID from the
attach function, so that it can be the main thread instead of
whichever we were told to attach to. */
signal_pid = pid;
*sigptr = mywait (statusptr, 0);
return 0;
}
extern int remote_debug;
/* Handle all of the extended 'q' packets. */
void
handle_query (char *own_buf)
{
static struct inferior_list_entry *thread_ptr;
if (strcmp ("qSymbol::", own_buf) == 0)
{
if (the_target->look_up_symbols != NULL)
(*the_target->look_up_symbols) ();
strcpy (own_buf, "OK");
return;
}
if (strcmp ("qfThreadInfo", own_buf) == 0)
{
thread_ptr = all_threads.head;
sprintf (own_buf, "m%lx", thread_ptr->id);
thread_ptr = thread_ptr->next;
return;
}
if (strcmp ("qsThreadInfo", own_buf) == 0)
{
if (thread_ptr != NULL)
{
sprintf (own_buf, "m%lx", thread_ptr->id);
thread_ptr = thread_ptr->next;
return;
}
else
{
sprintf (own_buf, "l");
return;
}
}
if (the_target->read_auxv != NULL
&& strncmp ("qPart:auxv:read::", own_buf, 17) == 0)
{
char data[(PBUFSIZ - 1) / 2];
CORE_ADDR ofs;
unsigned int len;
int n;
decode_m_packet (&own_buf[17], &ofs, &len); /* "OFS,LEN" */
if (len > sizeof data)
len = sizeof data;
n = (*the_target->read_auxv) (ofs, data, len);
if (n == 0)
write_ok (own_buf);
else if (n < 0)
write_enn (own_buf);
else
convert_int_to_ascii (data, own_buf, n);
return;
}
/* Otherwise we didn't know what packet it was. Say we didn't
understand it. */
own_buf[0] = 0;
}
/* Parse vCont packets. */
void
handle_v_cont (char *own_buf, char *status, unsigned char *signal)
{
char *p, *q;
int n = 0, i = 0;
struct thread_resume *resume_info, default_action;
/* Count the number of semicolons in the packet. There should be one
for every action. */
p = &own_buf[5];
while (p)
{
n++;
p++;
p = strchr (p, ';');
}
/* Allocate room for one extra action, for the default remain-stopped
behavior; if no default action is in the list, we'll need the extra
slot. */
resume_info = malloc ((n + 1) * sizeof (resume_info[0]));
default_action.thread = -1;
default_action.leave_stopped = 1;
default_action.step = 0;
default_action.sig = 0;
p = &own_buf[5];
i = 0;
while (*p)
{
p++;
resume_info[i].leave_stopped = 0;
if (p[0] == 's' || p[0] == 'S')
resume_info[i].step = 1;
else if (p[0] == 'c' || p[0] == 'C')
resume_info[i].step = 0;
else
goto err;
if (p[0] == 'S' || p[0] == 'C')
{
int sig;
sig = strtol (p + 1, &q, 16);
if (p == q)
goto err;
p = q;
if (!target_signal_to_host_p (sig))
goto err;
resume_info[i].sig = target_signal_to_host (sig);
}
else
{
resume_info[i].sig = 0;
p = p + 1;
}
if (p[0] == 0)
{
resume_info[i].thread = -1;
default_action = resume_info[i];
/* Note: we don't increment i here, we'll overwrite this entry
the next time through. */
}
else if (p[0] == ':')
{
resume_info[i].thread = strtoul (p + 1, &q, 16);
if (p == q)
goto err;
p = q;
if (p[0] != ';' && p[0] != 0)
goto err;
i++;
}
}
resume_info[i] = default_action;
/* Still used in occasional places in the backend. */
if (n == 1 && resume_info[0].thread != -1)
cont_thread = resume_info[0].thread;
else
cont_thread = -1;
set_desired_inferior (0);
(*the_target->resume) (resume_info);
free (resume_info);
*signal = mywait (status, 1);
prepare_resume_reply (own_buf, *status, *signal);
return;
err:
/* No other way to report an error... */
strcpy (own_buf, "");
free (resume_info);
return;
}
/* Handle all of the extended 'v' packets. */
void
handle_v_requests (char *own_buf, char *status, unsigned char *signal)
{
if (strncmp (own_buf, "vCont;", 6) == 0)
{
handle_v_cont (own_buf, status, signal);
return;
}
if (strncmp (own_buf, "vCont?", 6) == 0)
{
strcpy (own_buf, "vCont;c;C;s;S");
return;
}
/* Otherwise we didn't know what packet it was. Say we didn't
understand it. */
own_buf[0] = 0;
return;
}
void
myresume (int step, int sig)
{
struct thread_resume resume_info[2];
int n = 0;
if (step || sig || cont_thread > 0)
{
resume_info[0].thread
= ((struct inferior_list_entry *) current_inferior)->id;
resume_info[0].step = step;
resume_info[0].sig = sig;
resume_info[0].leave_stopped = 0;
n++;
}
resume_info[n].thread = -1;
resume_info[n].step = 0;
resume_info[n].sig = 0;
resume_info[n].leave_stopped = (cont_thread > 0);
(*the_target->resume) (resume_info);
}
static int attached;
static void
gdbserver_usage (void)
{
error ("Usage:\tgdbserver COMM PROG [ARGS ...]\n"
"\tgdbserver COMM --attach PID\n"
"\n"
"COMM may either be a tty device (for serial debugging), or \n"
"HOST:PORT to listen for a TCP connection.\n");
}
int
main (int argc, char *argv[])
{
char ch, status, *own_buf, mem_buf[2000];
int i = 0;
unsigned char signal;
unsigned int len;
CORE_ADDR mem_addr;
int bad_attach;
int pid;
char *arg_end;
if (setjmp (toplevel))
{
fprintf (stderr, "Exiting\n");
exit (1);
}
bad_attach = 0;
pid = 0;
attached = 0;
if (argc >= 3 && strcmp (argv[2], "--attach") == 0)
{
if (argc == 4
&& argv[3] != '\0'
&& (pid = strtoul (argv[3], &arg_end, 10)) != 0
&& *arg_end == '\0')
{
;
}
else
bad_attach = 1;
}
if (argc < 3 || bad_attach)
gdbserver_usage();
initialize_low ();
own_buf = malloc (PBUFSIZ);
if (pid == 0)
{
/* Wait till we are at first instruction in program. */
signal = start_inferior (&argv[2], &status);
/* We are now stopped at the first instruction of the target process */
}
else
{
switch (attach_inferior (pid, &status, &signal))
{
case -1:
error ("Attaching not supported on this target");
break;
default:
attached = 1;
break;
}
}
while (1)
{
remote_open (argv[1]);
restart:
setjmp (toplevel);
while (getpkt (own_buf) > 0)
{
unsigned char sig;
i = 0;
ch = own_buf[i++];
switch (ch)
{
case 'q':
handle_query (own_buf);
break;
case 'd':
remote_debug = !remote_debug;
break;
case 'D':
fprintf (stderr, "Detaching from inferior\n");
detach_inferior ();
write_ok (own_buf);
putpkt (own_buf);
remote_close ();
/* If we are attached, then we can exit. Otherwise, we need to
hang around doing nothing, until the child is gone. */
if (!attached)
{
int status, ret;
do {
ret = waitpid (signal_pid, &status, 0);
if (WIFEXITED (status) || WIFSIGNALED (status))
break;
} while (ret != -1 || errno != ECHILD);
}
exit (0);
case '!':
if (attached == 0)
{
extended_protocol = 1;
prepare_resume_reply (own_buf, status, signal);
}
else
{
/* We can not use the extended protocol if we are
attached, because we can not restart the running
program. So return unrecognized. */
own_buf[0] = '\0';
}
break;
case '?':
prepare_resume_reply (own_buf, status, signal);
break;
case 'H':
switch (own_buf[1])
{
case 'g':
general_thread = strtoul (&own_buf[2], NULL, 16);
write_ok (own_buf);
set_desired_inferior (1);
break;
case 'c':
cont_thread = strtoul (&own_buf[2], NULL, 16);
write_ok (own_buf);
break;
case 's':
step_thread = strtoul (&own_buf[2], NULL, 16);
write_ok (own_buf);
break;
default:
/* Silently ignore it so that gdb can extend the protocol
without compatibility headaches. */
own_buf[0] = '\0';
break;
}
break;
case 'g':
set_desired_inferior (1);
registers_to_string (own_buf);
break;
case 'G':
set_desired_inferior (1);
registers_from_string (&own_buf[1]);
write_ok (own_buf);
break;
case 'm':
decode_m_packet (&own_buf[1], &mem_addr, &len);
if (read_inferior_memory (mem_addr, mem_buf, len) == 0)
convert_int_to_ascii (mem_buf, own_buf, len);
else
write_enn (own_buf);
break;
case 'M':
decode_M_packet (&own_buf[1], &mem_addr, &len, mem_buf);
if (write_inferior_memory (mem_addr, mem_buf, len) == 0)
write_ok (own_buf);
else
write_enn (own_buf);
break;
case 'C':
convert_ascii_to_int (own_buf + 1, &sig, 1);
if (target_signal_to_host_p (sig))
signal = target_signal_to_host (sig);
else
signal = 0;
set_desired_inferior (0);
myresume (0, signal);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 'S':
convert_ascii_to_int (own_buf + 1, &sig, 1);
if (target_signal_to_host_p (sig))
signal = target_signal_to_host (sig);
else
signal = 0;
set_desired_inferior (0);
myresume (1, signal);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 'c':
set_desired_inferior (0);
myresume (0, 0);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 's':
set_desired_inferior (0);
myresume (1, 0);
signal = mywait (&status, 1);
prepare_resume_reply (own_buf, status, signal);
break;
case 'k':
fprintf (stderr, "Killing inferior\n");
kill_inferior ();
/* When using the extended protocol, we start up a new
debugging session. The traditional protocol will
exit instead. */
if (extended_protocol)
{
write_ok (own_buf);
fprintf (stderr, "GDBserver restarting\n");
/* Wait till we are at 1st instruction in prog. */
signal = start_inferior (&argv[2], &status);
goto restart;
break;
}
else
{
exit (0);
break;
}
case 'T':
if (mythread_alive (strtoul (&own_buf[1], NULL, 16)))
write_ok (own_buf);
else
write_enn (own_buf);
break;
case 'R':
/* Restarting the inferior is only supported in the
extended protocol. */
if (extended_protocol)
{
kill_inferior ();
write_ok (own_buf);
fprintf (stderr, "GDBserver restarting\n");
/* Wait till we are at 1st instruction in prog. */
signal = start_inferior (&argv[2], &status);
goto restart;
break;
}
else
{
/* It is a request we don't understand. Respond with an
empty packet so that gdb knows that we don't support this
request. */
own_buf[0] = '\0';
break;
}
case 'v':
/* Extended (long) request. */
handle_v_requests (own_buf, &status, &signal);
break;
default:
/* It is a request we don't understand. Respond with an
empty packet so that gdb knows that we don't support this
request. */
own_buf[0] = '\0';
break;
}
putpkt (own_buf);
if (status == 'W')
fprintf (stderr,
"\nChild exited with status %d\n", signal);
if (status == 'X')
fprintf (stderr, "\nChild terminated with signal = 0x%x\n",
signal);
if (status == 'W' || status == 'X')
{
if (extended_protocol)
{
fprintf (stderr, "Killing inferior\n");
kill_inferior ();
write_ok (own_buf);
fprintf (stderr, "GDBserver restarting\n");
/* Wait till we are at 1st instruction in prog. */
signal = start_inferior (&argv[2], &status);
goto restart;
break;
}
else
{
fprintf (stderr, "GDBserver exiting\n");
exit (0);
}
}
}
/* We come here when getpkt fails.
For the extended remote protocol we exit (and this is the only
way we gracefully exit!).
For the traditional remote protocol close the connection,
and re-open it at the top of the loop. */
if (extended_protocol)
{
remote_close ();
exit (0);
}
else
{
fprintf (stderr, "Remote side has terminated connection. "
"GDBserver will reopen the connection.\n");
remote_close ();
}
}
}