binutils-gdb/gdb/remote-bug.c

/* Remote debugging interface for Motorola's MVME187BUG monitor, an embedded
   monitor for the m88k.

   Copyright 1992, 1993 Free Software Foundation, Inc.
   Contributed by Cygnus Support.  Written by K. Richard Pixley.

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., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "defs.h"
#include "inferior.h"
#include "wait.h"
#include "value.h"
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <signal.h>
#include <setjmp.h>
#include <errno.h>
#include "terminal.h"
#include "target.h"
#include "gdbcore.h"
#include "serial.h"

/* External data declarations */
extern int stop_soon_quietly;	/* for wait_for_inferior */

/* Forward data declarations */
static struct target_ops bug_ops;	/* Forward declaration */

/* Forward function declarations */
static void bug_fetch_registers ();
static int bug_store_registers ();
static void bug_close ();
static int bug_clear_breakpoints ();

static int quiet = 1;


serial_t desc;

/***********************************************************************/
/* Caching stuff stolen from remote-nindy.c  */

/* The data cache records all the data read from the remote machine
   since the last time it stopped.

   Each cache block holds LINE_SIZE bytes of data
   starting at a multiple-of-LINE_SIZE address.  */

#define LINE_SIZE_POWER 4
#define LINE_SIZE (1<<LINE_SIZE_POWER)	/* eg 1<<3 == 8 */
#define LINE_SIZE_MASK ((LINE_SIZE-1))	/* eg 7*2+1= 111*/
#define DCACHE_SIZE 64		/* Number of cache blocks */
#define XFORM(x)  ((x&LINE_SIZE_MASK)>>2)
struct dcache_block
  {
    struct dcache_block *next, *last;
    unsigned int addr;		/* Address for which data is recorded.  */
    int data[LINE_SIZE / sizeof (int)];
  };

struct dcache_block dcache_free, dcache_valid;

/* Free all the data cache blocks, thus discarding all cached data.  */
static
void
dcache_flush ()
{
  register struct dcache_block *db;

  while ((db = dcache_valid.next) != &dcache_valid)
    {
      remque (db);
      insque (db, &dcache_free);
    }
}

/*
 * If addr is present in the dcache, return the address of the block
 * containing it.
 */
static
struct dcache_block *
dcache_hit (addr)
     unsigned int addr;
{
  register struct dcache_block *db;

  if (addr & 3)
    abort ();

  /* Search all cache blocks for one that is at this address.  */
  db = dcache_valid.next;
  while (db != &dcache_valid)
    {
      if ((addr & ~LINE_SIZE_MASK) == db->addr)
	return db;
      db = db->next;
    }
  return NULL;
}

/*  Return the int data at address ADDR in dcache block DC.  */
static
int
dcache_value (db, addr)
     struct dcache_block *db;
     unsigned int addr;
{
  if (addr & 3)
    abort ();
  return (db->data[XFORM (addr)]);
}

/* Get a free cache block, put or keep it on the valid list,
   and return its address.  The caller should store into the block
   the address and data that it describes, then remque it from the
   free list and insert it into the valid list.  This procedure
   prevents errors from creeping in if a ninMemGet is interrupted
   (which used to put garbage blocks in the valid list...).  */
static
struct dcache_block *
dcache_alloc ()
{
  register struct dcache_block *db;

  if ((db = dcache_free.next) == &dcache_free)
    {
      /* If we can't get one from the free list, take last valid and put
	 it on the free list.  */
      db = dcache_valid.last;
      remque (db);
      insque (db, &dcache_free);
    }

  remque (db);
  insque (db, &dcache_valid);
  return (db);
}

/* Return the contents of the word at address ADDR in the remote machine,
   using the data cache.  */
static
int
dcache_fetch (addr)
     CORE_ADDR addr;
{
  register struct dcache_block *db;

  db = dcache_hit (addr);
  if (db == 0)
    {
      db = dcache_alloc ();
      immediate_quit++;
      bug_read_inferior_memory (addr & ~LINE_SIZE_MASK, (unsigned char *) db->data, LINE_SIZE);
      immediate_quit--;
      db->addr = addr & ~LINE_SIZE_MASK;
      remque (db);		/* Off the free list */
      insque (db, &dcache_valid);	/* On the valid list */
    }
  return (dcache_value (db, addr));
}

/* Write the word at ADDR both in the data cache and in the remote machine.  */
static void
dcache_poke (addr, data)
     CORE_ADDR addr;
     int data;
{
  register struct dcache_block *db;

  /* First make sure the word is IN the cache.  DB is its cache block.  */
  db = dcache_hit (addr);
  if (db == 0)
    {
      db = dcache_alloc ();
      immediate_quit++;
      bug_write_inferior_memory (addr & ~LINE_SIZE_MASK, (unsigned char *) db->data, LINE_SIZE);
      immediate_quit--;
      db->addr = addr & ~LINE_SIZE_MASK;
      remque (db);		/* Off the free list */
      insque (db, &dcache_valid);	/* On the valid list */
    }

  /* Modify the word in the cache.  */
  db->data[XFORM (addr)] = data;

  /* Send the changed word.  */
  immediate_quit++;
  bug_write_inferior_memory (addr, (unsigned char *) &data, 4);
  immediate_quit--;
}

/* The cache itself. */
struct dcache_block the_cache[DCACHE_SIZE];

/* Initialize the data cache.  */
static void
dcache_init ()
{
  register i;
  register struct dcache_block *db;

  db = the_cache;
  dcache_free.next = dcache_free.last = &dcache_free;
  dcache_valid.next = dcache_valid.last = &dcache_valid;
  for (i = 0; i < DCACHE_SIZE; i++, db++)
    insque (db, &dcache_free);
}

/***********************************************************************
 * I/O stuff stolen from remote-eb.c
 ***********************************************************************/

static int timeout = 2;

static const char *dev_name;

/* Descriptor for I/O to remote machine.  Initialize it to -1 so that
   bug_open knows that we don't have a file open when the program
   starts.  */

int is_open = 0;
int
check_open ()
{
  if (!is_open)
    {
      error ("remote device not open");
    }
}

#define ON	1
#define OFF	0

/* Read a character from the remote system, doing all the fancy
   timeout stuff.  */
static int
readchar ()
{
  int buf;

  buf = SERIAL_READCHAR (desc, timeout);

  if (buf == SERIAL_TIMEOUT)
    error ("Timeout reading from remote system.");

  if (!quiet)
    printf ("%c", buf);

  return buf & 0x7f;
}

static int
readchar_nofail ()
{
  int buf;

  buf = SERIAL_READCHAR (desc, timeout);
  if (buf == SERIAL_TIMEOUT)
    buf = 0;
  if (!quiet)
    printf ("%c", buf);

  return buf & 0x7f;

}

/* Keep discarding input from the remote system, until STRING is found.
   Let the user break out immediately.  */
static void
expect (string)
     char *string;
{
  char *p = string;

  immediate_quit = 1;
  while (1)
    {
      if (readchar () == *p)
	{
	  p++;
	  if (*p == '\0')
	    {
	      immediate_quit = 0;
	      return;
	    }
	}
      else
	p = string;
    }
}

/* Keep discarding input until we see the bug prompt.

   The convention for dealing with the prompt is that you
   o give your command
   o *then* wait for the prompt.

   Thus the last thing that a procedure does with the serial line
   will be an expect_prompt().  Exception:  bug_resume does not
   wait for the prompt, because the terminal is being handed over
   to the inferior.  However, the next thing which happens after that
   is a bug_wait which does wait for the prompt.
   Note that this includes abnormal exit, e.g. error().  This is
   necessary to prevent getting into states from which we can't
   recover.  */
static void
expect_prompt ()
{
  expect ("Bug>");
}

/* Get a hex digit from the remote system & return its value.
   If ignore_space is nonzero, ignore spaces (not newline, tab, etc).  */
static int
get_hex_digit (ignore_space)
     int ignore_space;
{
  int ch;

  while (1)
    {
      ch = readchar ();
      if (ch >= '0' && ch <= '9')
	return ch - '0';
      else if (ch >= 'A' && ch <= 'F')
	return ch - 'A' + 10;
      else if (ch >= 'a' && ch <= 'f')
	return ch - 'a' + 10;
      else if (ch == ' ' && ignore_space)
	;
      else
	{
	  expect_prompt ();
	  error ("Invalid hex digit from remote system.");
	}
    }
}

/* Get a byte from bug_desc and put it in *BYT.  Accept any number
   leading spaces.  */
static void
get_hex_byte (byt)
     char *byt;
{
  int val;

  val = get_hex_digit (1) << 4;
  val |= get_hex_digit (0);
  *byt = val;
}

/* Read a 32-bit hex word from the bug, preceded by a space  */
static long
get_hex_word ()
{
  long val;
  int j;

  val = 0;
  for (j = 0; j < 8; j++)
    val = (val << 4) + get_hex_digit (j == 0);
  return val;
}

/* Called when SIGALRM signal sent due to alarm() timeout.  */

/* Number of SIGTRAPs we need to simulate.  That is, the next
   NEED_ARTIFICIAL_TRAP calls to bug_wait should just return
   SIGTRAP without actually waiting for anything.  */

static int need_artificial_trap = 0;

void
bug_kill (arg, from_tty)
     char *arg;
     int from_tty;
{

}

/*
 * Download a file specified in 'args', to the bug.
 */
static void
bug_load (args, fromtty)
     char *args;
     int fromtty;
{
  bfd *abfd;
  asection *s;
  int n;
  char buffer[1024];

  check_open ();

  dcache_flush ();
  inferior_pid = 0;
  abfd = bfd_openr (args, 0);
  if (!abfd)
    {
      printf_filtered ("Unable to open file %s\n", args);
      return;
    }

  if (bfd_check_format (abfd, bfd_object) == 0)
    {
      printf_filtered ("File is not an object file\n");
      return;
    }

  s = abfd->sections;
  while (s != (asection *) NULL)
    {
      if (s->flags & SEC_LOAD)
	{
	  int i;

#define DELTA (1024)
	  char *buffer = xmalloc (DELTA);

	  printf_filtered ("%s\t: 0x%4x .. 0x%4x  ", s->name, s->vma, s->vma + s->_raw_size);
	  for (i = 0; i < s->_raw_size; i += DELTA)
	    {
	      int delta = DELTA;

	      if (delta > s->_raw_size - i)
		delta = s->_raw_size - i;

	      bfd_get_section_contents (abfd, s, buffer, i, delta);
	      bug_write_inferior_memory (s->vma + i, buffer, delta);
	      printf_filtered ("*");
	      fflush (stdout);
	    }
	  printf_filtered ("\n");
	  free (buffer);
	}
      s = s->next;
    }
  sprintf (buffer, "rs ip %x", abfd->start_address);
  bug_write_cr (buffer);
  expect_prompt ();
}

/* This is called not only when we first attach, but also when the
   user types "run" after having attached.  */
void
bug_create_inferior (execfile, args, env)
     char *execfile;
     char *args;
     char **env;
{
  int entry_pt;
  char buffer[100];

  if (args && *args)
    error ("Can't pass arguments to remote bug process.");

  if (execfile == 0 || exec_bfd == 0)
    error ("No exec file specified");

  entry_pt = (int) bfd_get_start_address (exec_bfd);
  check_open ();

  bug_kill (NULL, NULL);
  bug_clear_breakpoints ();
  init_wait_for_inferior ();
  bug_write_cr ("");
  expect_prompt ();

  insert_breakpoints ();	/* Needed to get correct instruction in cache */
  proceed (entry_pt, -1, 0);
}

/* Open a connection to a remote debugger.
   NAME is the filename used for communication, then a space,
   then the baud rate.
 */

static char *
find_end_of_word (s)
     char *s;
{
  while (*s && !isspace (*s))
    s++;
  return s;
}

static char *
get_word (p)
     char **p;
{
  char *s = *p;
  char *word;
  char *copy;
  size_t len;

  while (isspace (*s))
    s++;

  word = s;

  len = 0;

  while (*s && !isspace (*s))
    {
      s++;
      len++;

    }
  copy = xmalloc (len + 1);
  memcpy (copy, word, len);
  copy[len] = 0;
  *p = s;
  return copy;
}

static int baudrate = 9600;

#if 0
static int
is_baudrate_right ()
{
  int ok;

  /* Put this port into NORMAL mode, send the 'normal' character */

  bug_write ("\001", 1);	/* Control A */
  bug_write ("\r", 1);		/* Cr */

  while (1)
    {
      ok = SERIAL_READCHAR (desc, timeout);
      if (ok < 0)
	break;
    }

  bug_write ("r", 1);

  if (readchar_nofail () == 'r')
    return 1;

  /* Not the right baudrate, or the board's not on */
  return 0;
}
#endif /* not */

static void
set_rate ()
{
  if (!SERIAL_SETBAUDRATE (desc, baudrate))
    error ("Can't set baudrate");
}


static void
bug_open (name, from_tty)
     char *name;
     int from_tty;
{
  unsigned int prl;
  char *p;

  push_target (&bug_ops);

  if (name == 0)
    {
      name = "";
    }
  if (is_open)
    bug_close (0);
  dev_name = strdup (name);

  if (!(desc = SERIAL_OPEN (dev_name)))
    perror_with_name ((char *) dev_name);

  SERIAL_RAW (desc);
  is_open = 1;

  dcache_init ();

  /* Hello?  Are you there?  */
  SERIAL_WRITE (desc, "\r", 1);
  expect_prompt ();

  /* Clear any break points */
  bug_clear_breakpoints ();

  printf_filtered ("Connected to remote 187bug system.\n");
}

/* Close out all files and local state before this target loses control. */

static void
bug_close (quitting)
     int quitting;
{
  /* Clear any break points */
  bug_clear_breakpoints ();

  if (is_open)
    SERIAL_CLOSE (desc);

  is_open = 0;
}

/* Terminate the open connection to the remote debugger.
   Use this when you want to detach and do something else
   with your gdb.  */
void
bug_detach (args, from_tty)
     char *args;
     int from_tty;
{
  if (is_open)
    bug_clear_breakpoints ();

  pop_target ();		/* calls bug_close to do the real work */

  if (from_tty)
    printf_filtered ("Ending remote %s debugging\n", target_shortname);
}

/* Tell the remote machine to resume.  */

void
bug_resume (step, sig)
     int step, sig;
{
  dcache_flush ();

  if (step)
    {
      bug_write_cr("t");

      /* Force the next bug_wait to return a trap.  Not doing anything
       about I/O from the target means that the user has to type
       "continue" to see any.  FIXME, this should be fixed.  */
      need_artificial_trap = 1;
    }
  else
      bug_write_cr ("g");

  return;
}

/* Wait until the remote machine stops, then return,
   storing status in STATUS just as `wait' would.  */

int
not_bug_wait (status)
     WAITTYPE *status;
{
  int old_timeout;
  int old_quit;
  int i;

  expect("Effective address: ");
  i = get_hex_word();
  expect("\r");

  WSETEXIT ((*status), 0);

  old_timeout = timeout;
  timeout = 99999;		/* while user program runs. */
  old_quit = immediate_quit;
  immediate_quit = 1; /* helps ability to quit. */

  while (strchr("\n\r", i = readchar()) != NULL) ;;

  immediate_quit = old_quit;
  timeout = old_timeout;

  if (i == 'A')
    {
/* At Breakpoint */
      expect("t Breakpoint");
      WSETSTOP ((*status), SIGTRAP);

    }
  else
    {
/* finished cleanly */
      ;
    }

  expect_prompt();
}

int
bug_wait (status)
     WAITTYPE *status;
{
  /* Strings to look for.  '?' means match any single character.
     Note that with the algorithm we use, the initial character
     of the string cannot recur in the string, or we will not
     find some cases of the string in the input.  */

  static char bpt[] = "At Breakpoint";
  static char exitmsg[] = "????-Bug>";
  char *bp = bpt;
  char *ep = exitmsg;

  /* Large enough for either sizeof (bpt) or sizeof (exitmsg) chars.  */
  char swallowed[50];

  /* Current position in swallowed.  */
  char *swallowed_p = swallowed;

  int ch;
  int ch_handled;
  int old_timeout = timeout;
  int old_immediate_quit = immediate_quit;
  int swallowed_cr = 0;

  WSETEXIT ((*status), 0);

  if (need_artificial_trap != 0)
    {
      WSETSTOP ((*status), SIGTRAP);
      need_artificial_trap--;
      /* user output from the target can be discarded here. (?) */
      expect_prompt();
      return 0;
    }

  /* read off leftovers from resume */
  expect("Effective address: ");
  (void) get_hex_word();
  while (strchr("\r\n", ch = readchar()) != NULL) ;;

  timeout = 99999;		/* Don't time out -- user program is running. */
  immediate_quit = 1;		/* Helps ability to QUIT */
  while (1)
    {
      QUIT;			/* Let user quit and leave process running */
      ch_handled = 0;
      if (ch == *bp)
	{
	  bp++;
	  if (*bp == '\0')
	    break;
	  ch_handled = 1;

	  *swallowed_p++ = ch;
	}
      else
	{
	  bp = bpt;
	}
      if (ch == *ep || *ep == '?')
	{
	  ep++;
	  if (*ep == '\0')
	    break;

	  if (!ch_handled)
	    *swallowed_p++ = ch;
	  ch_handled = 1;
	}
      else
	{
	  ep = exitmsg;
	}

      if (!ch_handled)
	{
	  char *p;

	  /* Print out any characters which have been swallowed.  */
	  for (p = swallowed; p < swallowed_p; ++p)
	    putc (*p, stdout);
	  swallowed_p = swallowed;

	  if ((ch != '\r' && ch != '\n') || swallowed_cr > 10)
	    {
	      putc (ch, stdout);
	      swallowed_cr = 10;
	    }
	  swallowed_cr++;

	}

      ch = readchar ();
    }
  if (*bp == '\0')
    {
      WSETSTOP ((*status), SIGTRAP);
      expect_prompt ();
    }
  else
    {
      WSETEXIT ((*status), 0);
    }

  timeout = old_timeout;
  immediate_quit = old_immediate_quit;
  return 0;
}

/* Return the name of register number REGNO
   in the form input and output by bug.

   Returns a pointer to a static buffer containing the answer.  */
static char *
get_reg_name (regno)
     int regno;
{
  static char *rn[] = {
    "r00", "r01", "r02", "r03", "r04", "r05", "r06", "r07",
    "r08", "r09", "r10", "r11", "r12", "r13", "r14", "r15",
    "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
    "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",

    /* these get confusing because we omit a few and switch some ordering around. */

    "cr01",  /* 32 = psr */
    "fcr62", /* 33 = fpsr*/
    "fcr63", /* 34 = fpcr */
    "cr04",  /* 35 = sxip */
    "cr05", /* 36 = snip */
    "cr06", /* 37 = sfip */
  };

  return rn[regno];
}

static int
gethex (length, start, ok)
     unsigned int length;
     char *start;
     int *ok;
{
  int result = 0;

  while (length--)
    {
      result <<= 4;
      if (*start >= 'a' && *start <= 'f')
	{
	  result += *start - 'a' + 10;
	}
      else if (*start >= 'A' && *start <= 'F')
	{
	  result += *start - 'A' + 10;
	}
      else if (*start >= '0' && *start <= '9')
	{
	  result += *start - '0';
	}
      else
	*ok = 0;
      start++;

    }
  return result;
}
static int
timed_read (buf, n, timeout)
     char *buf;

{
  int i;
  char c;

  i = 0;
  while (i < n)
    {
      c = readchar ();

      if (c == 0)
	return i;
      buf[i] = c;
      i++;

    }
  return i;
}

bug_write (a, l)
     char *a;
{
  int i;

  SERIAL_WRITE (desc, a, l);

  if (!quiet)
    for (i = 0; i < l; i++)
      {
	printf ("%c", a[i]);
      }
}

bug_write_cr (s)
     char *s;
{
  bug_write (s, strlen (s));
  bug_write ("\r", 1);
}

/* Store register REGNO, or all if REGNO == -1. */

static void
bug_fetch_register(regno)
     int regno;
{
  REGISTER_TYPE regval;
  check_open();

  if (regno == -1)
    {
      int i;

      for (i = 0; i < NUM_REGS; ++i)
	bug_fetch_register(i);
    }
  else
    {
      bug_write("rs ", 3);
      bug_write_cr(get_reg_name(regno));
      expect("=");
      regval = get_hex_word();
      expect_prompt();

      /* the following registers contain flag bits in the lower to bit slots.
	 Mask them off */
      if (regno == PC_REGNUM	/* aka sxip */
	  || regno == NPC_REGNUM /* aka snip */
	  || regno == SFIP_REGNUM)	/* aka sfip */
	regval &= ~0x3;

      supply_register(regno, (char *) &regval);
    }

  return;
}

/* Store register REGNO, or all if REGNO == -1. */

static void
bug_store_register (regno)
     int regno;
{
  REGISTER_TYPE regval;
  char buffer[1024];
  check_open();

  if (regno == -1)
    {
      int i;

      for (i = 0; i < NUM_REGS; ++i)
	bug_store_register(i);
    }
  else
    {
      char *regname;

      /* get_reg_name thinks that the pc is in sxip.  This is only partially
	 true.  When *assigning* it, we must assign to ip on m88k-bug. */

      regname = ((regno == PC_REGNUM)
		 ? "ip"
		 : get_reg_name(regno));

      sprintf(buffer, "rs %s %08x",
	      regname,
	      read_register(regno));

      bug_write_cr(buffer);
      expect_prompt();
    }

  return;
}

/* Get ready to modify the registers array.  On machines which store
   individual registers, this doesn't need to do anything.  On machines
   which store all the registers in one fell swoop, this makes sure
   that registers contains all the registers from the program being
   debugged.  */

void
bug_prepare_to_store ()
{
  /* Do nothing, since we can store individual regs */
}

static CORE_ADDR
translate_addr (addr)
     CORE_ADDR addr;
{

  return (addr);

}

/* Read a word from remote address ADDR and return it.
 * This goes through the data cache.
 */
int
bug_fetch_word (addr)
     CORE_ADDR addr;
{
  return dcache_fetch (addr);
}

/* Write a word WORD into remote address ADDR.
   This goes through the data cache.  */

void
bug_store_word (addr, word)
     CORE_ADDR addr;
     int word;
{
  dcache_poke (addr, word);
}

int
bug_xfer_inferior_memory (memaddr, myaddr, len, write, target)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
     int write;
     struct target_ops *target;	/* ignored */
{
  register int i;

  /* Round starting address down to longword boundary.  */
  register CORE_ADDR addr;

  /* Round ending address up; get number of longwords that makes.  */
  register int count;

  /* Allocate buffer of that many longwords.  */
  register int *buffer;

  addr = memaddr & -sizeof (int);
  count = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);

  buffer = (int *) alloca (count * sizeof (int));

  if (write)
    {
      /* Fill start and end extra bytes of buffer with existing memory data.  */

      if (addr != memaddr || len < (int) sizeof (int))
	{
	  /* Need part of initial word -- fetch it.  */
	  buffer[0] = bug_fetch_word (addr);
	}

      if (count > 1)		/* FIXME, avoid if even boundary */
	{
	  buffer[count - 1]
	    = bug_fetch_word (addr + (count - 1) * sizeof (int));
	}

      /* Copy data to be written over corresponding part of buffer */

      bcopy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);

      /* Write the entire buffer.  */

      for (i = 0; i < count; i++, addr += sizeof (int))
	{
	  errno = 0;
	  bug_store_word (addr, buffer[i]);
	  if (errno)
	    {

	      return 0;
	    }

	}
    }
  else
    {
      /* Read all the longwords */
      for (i = 0; i < count; i++, addr += sizeof (int))
	{
	  errno = 0;
	  buffer[i] = bug_fetch_word (addr);
	  if (errno)
	    {
	      return 0;
	    }
	  QUIT;
	}

      /* Copy appropriate bytes out of the buffer.  */
      bcopy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
    }

  return len;
}

/* fixme: make this user settable */
#define CHUNK_SIZE (30)

int
bug_write_inferior_memory (memaddr, myaddr, len)
     CORE_ADDR memaddr;
     unsigned char *myaddr;
     int len;
{
  int done;
  int todo;
  int checksum;
  char buffer[(CHUNK_SIZE + 8) << 1];

  done = 0;

#define LOAD_COMMAND "lo 0"
  bug_write_cr (LOAD_COMMAND);

  while (done < len)
    {
      int thisgo;
      int idx;
      char *buf = buffer;
      CORE_ADDR address;

      checksum = 0;
      thisgo = len - done;
      if (thisgo > CHUNK_SIZE)
	thisgo = CHUNK_SIZE;

      address = memaddr + done;
      sprintf (buf, "S3%02X%08X", thisgo + 4 + 1, address);
      buf += 12;

      checksum += (thisgo + 4 + 1
		   + (address & 0xff)
		   + ((address >>  8) & 0xff)
		   + ((address >> 16) & 0xff)
		   + ((address >> 24) & 0xff));

      for (idx = 0; idx < thisgo; idx++)
	{
	  sprintf (buf, "%02X", myaddr[idx + done]);
	  checksum += myaddr[idx + done];
	  buf += 2;
	}
      sprintf(buf, "%02X", ~checksum & 0xff);
      bug_write_cr (buffer);
      done += thisgo;
    }

  bug_write_cr("S7060000000000F9");
  expect_prompt();
}

void
bug_files_info ()
{
  char *file = "nothing";

  if (exec_bfd)
    file = bfd_get_filename (exec_bfd);

  if (exec_bfd)
#ifdef __GO32__
    printf_filtered ("\tAttached to DOS asynctsr and running program %s\n", file);
#else
    printf_filtered ("\tAttached to %s at %d baud and running program %s\n", dev_name, baudrate, file);
#endif
  printf_filtered ("\ton an m88k processor.\n");
}

/* Copy LEN bytes of data from debugger memory at MYADDR
   to inferior's memory at MEMADDR.  Returns errno value.
 * sb/sh instructions don't work on unaligned addresses, when TU=1.
 */

/* Read LEN bytes from inferior memory at MEMADDR.  Put the result
   at debugger address MYADDR.  Returns errno value.  */
int
bug_read_inferior_memory (memaddr, myaddr, len)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
{
  char request[100];
  char *buffer;
  char *p;
  char type;
  char size;
  unsigned char c;
  unsigned int inaddr;
  unsigned int checksum;

  sprintf(request, "du 0 %x:&%d", memaddr, len);
  bug_write_cr(request);

  p = buffer = alloca(len);

  /* scan up through the header */
  expect("S0030000FC");

  while (p < buffer + len)
    {
      /* scan off any white space. */
      while (readchar() != 'S') ;;

      /* what kind of s-rec? */
      type = readchar();

      /* scan record size */
      get_hex_byte(&size);
      checksum = size;
      --size;
      inaddr = 0;

      switch (type)
	{
	case '7':
	case '8':
	case '9':
	  goto done;

	case '3':
	  get_hex_byte(&c);
	  inaddr = (inaddr << 8) + c;
	  checksum += c;
	  --size;
	  /* intentional fall through */
	case '2':
	  get_hex_byte(&c);
	  inaddr = (inaddr << 8) + c;
	  checksum += c;
	  --size;
	  /* intentional fall through */
	case '1':
	  get_hex_byte(&c);
	  inaddr = (inaddr << 8) + c;
	  checksum += c;
	  --size;
	  get_hex_byte(&c);
	  inaddr = (inaddr << 8) + c;
	  checksum += c;
	  --size;
	  break;

	default:
	  /* bonk */
	  error("reading s-records.");
	}

      if (inaddr < memaddr
	  || (memaddr + len) < (inaddr + size))
	error("srec out of memory range.");

      if (p != buffer + inaddr - memaddr)
	error("srec out of sequence.");

      for (; size; --size, ++p)
	{
	  get_hex_byte(p);
	  checksum += *p;
	}

      get_hex_byte(&c);
      if (c != (~checksum & 0xff))
	error("bad s-rec checksum");
    }

 done:
  expect_prompt();
  if (p != buffer + len)
    return(1);

  memcpy(myaddr, buffer, len);
  return(0);
}

/* This routine is run as a hook, just before the main command loop is
   entered.  If gdb is configured for the H8, but has not had its
   target specified yet, this will loop prompting the user to do so.
*/

bug_before_main_loop ()
{
  char ttyname[100];
  char *p, *p2;
  extern FILE *instream;

  push_target (&bug_ops);
}

#define MAX_BREAKS	16
static int num_brkpts = 0;
static int
bug_insert_breakpoint (addr, save)
     CORE_ADDR addr;
     char *save;		/* Throw away, let bug save instructions */
{
  check_open ();

  if (num_brkpts < MAX_BREAKS)
    {
      char buffer[100];

      num_brkpts++;
      sprintf (buffer, "br %x", addr);
      bug_write_cr (buffer);
      expect_prompt ();
      return(0);
    }
  else
    {
      fprintf_filtered (stderr,
		      "Too many break points, break point not installed\n");
      return(1);
    }

}
static int
bug_remove_breakpoint (addr, save)
     CORE_ADDR addr;
     char *save;		/* Throw away, let bug save instructions */
{
  if (num_brkpts > 0)
    {
      char buffer[100];

      num_brkpts--;
      sprintf (buffer, "nobr %x", addr);
      bug_write_cr (buffer);
      expect_prompt ();

    }
  return (0);
}

/* Clear the bugs notion of what the break points are */
static int
bug_clear_breakpoints ()
{

  if (is_open)
    {
      bug_write_cr ("nobr");
      expect_prompt ();
    }
  num_brkpts = 0;
}
static void
bug_mourn ()
{
  bug_clear_breakpoints ();
  generic_mourn_inferior ();
}

/* Put a command string, in args, out to the bug.  The bug is assumed to
   be in raw mode, all writing/reading done through desc.
   Ouput from the bug is placed on the users terminal until the
   prompt from the bug is seen.
   FIXME: Can't handle commands that take input.  */

void
bug_com (args, fromtty)
     char *args;
     int fromtty;
{
  check_open ();

  if (!args)
    return;

  /* Clear all input so only command relative output is displayed */

  bug_write_cr (args);
  bug_write ("\030", 1);
  expect_prompt ();
}

bug_quiet ()
{
  quiet = !quiet;
  if (quiet)
    printf_filtered ("Snoop disabled\n");
  else
    printf_filtered ("Snoop enabled\n");

}

bug_device (s)
     char *s;
{
  if (s)
    {
      dev_name = get_word (&s);
    }
}

#if 0
static
bug_speed (s)
     char *s;
{
  check_open ();

  if (s)
    {
      char buffer[100];
      int newrate = atoi (s);
      int which = 0;

      if (SERIAL_SETBAUDRATE (desc, newrate))
	error ("Can't use %d baud\n", newrate);

      printf_filtered ("Checking target is in sync\n");

      printf_filtered ("Sending commands to set target to %d\n",
		       baudrate);

      sprintf (buffer, "tm %d. N 8 1", baudrate);
      bug_write_cr (buffer);
    }
}
#endif /* 0 */

static struct target_ops bug_ops =
{
  "bug", "Remote BUG monitor",
  "Use the mvme187 board running the BUG monitor connected\n\
by a serial line.",

  bug_open, bug_close,
  0, bug_detach, bug_resume, bug_wait,	/* attach */
  bug_fetch_register, bug_store_register,
  bug_prepare_to_store,
  bug_xfer_inferior_memory,
  bug_files_info,
  bug_insert_breakpoint, bug_remove_breakpoint,	/* Breakpoints */
  0, 0, 0, 0, 0,		/* Terminal handling */
  bug_kill,			/* FIXME, kill */
  bug_load,
  0,				/* lookup_symbol */
  bug_create_inferior,		/* create_inferior */
  bug_mourn,			/* mourn_inferior FIXME */
  0,				/* can_run */
  0,				/* notice_signals */
  process_stratum, 0,		/* next */
  1, 1, 1, 1, 1,		/* all mem, mem, stack, regs, exec */
  0, 0,				/* Section pointers */
  OPS_MAGIC,			/* Always the last thing */
};

void
_initialize_remote_bug ()
{
  add_target (&bug_ops);

  add_com ("bug <command>", class_obscure, bug_com,
	   "Send a command to the BUG monitor.");
  add_com ("snoop", class_obscure, bug_quiet,
	   "Show what commands are going to the monitor");

  add_com ("device", class_obscure, bug_device,
	   "Set the terminal line for BUG communications");

#if 0
  add_com ("speed", class_obscure, bug_speed,
	   "Set the terminal line speed for BUG communications");
#endif /* 0 */

  dev_name = NULL;
}