server.c

xen虚拟机源代码安装包

/* Main code for remote server for GDB.
   Copyright 1989, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2002, 2003, 2004
   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 "linux-low.h"
#include <unistd.h>
#include <signal.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

int cont_thread;
int general_thread;
int step_thread;
int thread_from_wait;
int old_thread_from_wait;
int extended_protocol;
int server_waiting;
int isfile = 0;

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.  */

int 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 = %d\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 ("qC", own_buf) == 0)
    {
      struct process_info *process;
      if (current_inferior == NULL)
	return;
      process = get_thread_process(current_inferior);
      sprintf(own_buf, "QC%x", process->thread_known ? process->tid : 0);

    }
  if (strcmp ("qfThreadInfo", own_buf) == 0)
    {
      thread_ptr = all_threads.head;
      sprintf (own_buf, "m%x", thread_ptr->id);
      thread_ptr = thread_ptr->next;
      return;
    }

  if (strcmp ("qsThreadInfo", own_buf) == 0)
    {
      if (thread_ptr != NULL)
	{
	  sprintf (own_buf, "m%x", 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 = strtol (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
handle_breakpoint_requests (char *own_buf, char *status, unsigned char *signal)
{
  /*  Currently we only support software breakpoints */
    switch (own_buf[1]) {
        case '0': /* software breakpoint, int3 based */
	      own_buf[0] = '\0';
            break;
        case '1': /* hardware breakpoint */
        default:
		  write_enn (own_buf);
            break;
    }
}

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"
	 "\tgdbserver COMM --file COREFILE\n"
	 "\n"
	 "COMM may either be a tty device (for serial debugging), or \n"
	 "HOST:PORT to listen for a TCP connection.\n");
}