/* Native-dependent code for GDB, for NYU Ultra3 running Sym1 OS.
   Copyright 1988, 1989, 1991, 1992, 2001 Free Software Foundation,
   Inc.
   Contributed by David Wood (wood@nyu.edu) at New York University.

   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.  */

#define DEBUG
#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "symtab.h"
#include "value.h"
#include "regcache.h"

#include <sys/types.h>
#include <sys/param.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <fcntl.h>

#include "gdbcore.h"

#include <sys/file.h>
#include "gdb_stat.h"

static void fetch_core_registers (char *, unsigned, int, CORE_ADDR);

/* Assumes support for AMD's Binary Compatibility Standard
   for ptrace().  If you define ULTRA3, the ultra3 extensions to
   ptrace() are used allowing the reading of more than one register
   at a time. 

   This file assumes KERNEL_DEBUGGING is turned off.  This means
   that if the user/gdb tries to read gr64-gr95 or any of the 
   protected special registers we silently return -1 (see the
   CANNOT_STORE/FETCH_REGISTER macros).  */
#define	ULTRA3

#if !defined (offsetof)
#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
#endif

extern int errno;
struct ptrace_user pt_struct;

/* Get all available registers from the inferior.  Registers that are
 * defined in REGISTER_NAMES, but not available to the user/gdb are
 * supplied as -1.  This may include gr64-gr95 and the protected special
 * purpose registers.
 */

void
fetch_inferior_registers (int regno)
{
  register int i, j, ret_val = 0;
  char buf[128];

  if (regno != -1)
    {
      fetch_register (regno);
      return;
    }

/* Global Registers */
#ifdef ULTRA3
  errno = 0;
  ptrace (PT_READ_STRUCT, inferior_pid,
	  (PTRACE_ARG3_TYPE) register_addr (GR96_REGNUM, 0),
	  (int) &pt_struct.pt_gr[0], 32 * 4);
  if (errno != 0)
    {
      perror_with_name ("reading global registers");
      ret_val = -1;
    }
  else
    for (regno = GR96_REGNUM, j = 0; j < 32; regno++, j++)
      {
	supply_register (regno, &pt_struct.pt_gr[j]);
      }
#else
  for (regno = GR96_REGNUM; !ret_val && regno < GR96_REGNUM + 32; regno++)
    fetch_register (regno);
#endif

/* Local Registers */
#ifdef ULTRA3
  errno = 0;
  ptrace (PT_READ_STRUCT, inferior_pid,
	  (PTRACE_ARG3_TYPE) register_addr (LR0_REGNUM, 0),
	  (int) &pt_struct.pt_lr[0], 128 * 4);
  if (errno != 0)
    {
      perror_with_name ("reading local registers");
      ret_val = -1;
    }
  else
    for (regno = LR0_REGNUM, j = 0; j < 128; regno++, j++)
      {
	supply_register (regno, &pt_struct.pt_lr[j]);
      }
#else
  for (regno = LR0_REGNUM; !ret_val && regno < LR0_REGNUM + 128; regno++)
    fetch_register (regno);
#endif

/* Special Registers */
  fetch_register (GR1_REGNUM);
  fetch_register (CPS_REGNUM);
  fetch_register (PC_REGNUM);
  fetch_register (NPC_REGNUM);
  fetch_register (PC2_REGNUM);
  fetch_register (IPC_REGNUM);
  fetch_register (IPA_REGNUM);
  fetch_register (IPB_REGNUM);
  fetch_register (Q_REGNUM);
  fetch_register (BP_REGNUM);
  fetch_register (FC_REGNUM);

/* Fake any registers that are in REGISTER_NAMES, but not available to gdb */
  registers_fetched ();
}

/* Store our register values back into the inferior.
 * If REGNO is -1, do this for all registers.
 * Otherwise, REGNO specifies which register (so we can save time).  
 * NOTE: Assumes AMD's binary compatibility standard. 
 */

void
store_inferior_registers (int regno)
{
  register unsigned int regaddr;
  char buf[80];

  if (regno >= 0)
    {
      if (CANNOT_STORE_REGISTER (regno))
	return;
      regaddr = register_addr (regno, 0);
      errno = 0;
      ptrace (PT_WRITE_U, inferior_pid,
	      (PTRACE_ARG3_TYPE) regaddr, read_register (regno));
      if (errno != 0)
	{
	  sprintf (buf, "writing register %s (#%d)", REGISTER_NAME (regno), regno);
	  perror_with_name (buf);
	}
    }
  else
    {
#ifdef ULTRA3
      pt_struct.pt_gr1 = read_register (GR1_REGNUM);
      for (regno = GR96_REGNUM; regno < GR96_REGNUM + 32; regno++)
	pt_struct.pt_gr[regno] = read_register (regno);
      for (regno = LR0_REGNUM; regno < LR0_REGNUM + 128; regno++)
	pt_struct.pt_gr[regno] = read_register (regno);
      errno = 0;
      ptrace (PT_WRITE_STRUCT, inferior_pid,
	      (PTRACE_ARG3_TYPE) register_addr (GR1_REGNUM, 0),
	      (int) &pt_struct.pt_gr1, (1 * 32 * 128) * 4);
      if (errno != 0)
	{
	  sprintf (buf, "writing all local/global registers");
	  perror_with_name (buf);
	}
      pt_struct.pt_psr = read_register (CPS_REGNUM);
      pt_struct.pt_pc0 = read_register (NPC_REGNUM);
      pt_struct.pt_pc1 = read_register (PC_REGNUM);
      pt_struct.pt_pc2 = read_register (PC2_REGNUM);
      pt_struct.pt_ipc = read_register (IPC_REGNUM);
      pt_struct.pt_ipa = read_register (IPA_REGNUM);
      pt_struct.pt_ipb = read_register (IPB_REGNUM);
      pt_struct.pt_q = read_register (Q_REGNUM);
      pt_struct.pt_bp = read_register (BP_REGNUM);
      pt_struct.pt_fc = read_register (FC_REGNUM);
      errno = 0;
      ptrace (PT_WRITE_STRUCT, inferior_pid,
	      (PTRACE_ARG3_TYPE) register_addr (CPS_REGNUM, 0),
	      (int) &pt_struct.pt_psr, (10) * 4);
      if (errno != 0)
	{
	  sprintf (buf, "writing all special registers");
	  perror_with_name (buf);
	  return;
	}
#else
      store_inferior_registers (GR1_REGNUM);
      for (regno = GR96_REGNUM; regno < GR96_REGNUM + 32; regno++)
	store_inferior_registers (regno);
      for (regno = LR0_REGNUM; regno < LR0_REGNUM + 128; regno++)
	store_inferior_registers (regno);
      store_inferior_registers (CPS_REGNUM);
      store_inferior_registers (PC_REGNUM);
      store_inferior_registers (NPC_REGNUM);
      store_inferior_registers (PC2_REGNUM);
      store_inferior_registers (IPC_REGNUM);
      store_inferior_registers (IPA_REGNUM);
      store_inferior_registers (IPB_REGNUM);
      store_inferior_registers (Q_REGNUM);
      store_inferior_registers (BP_REGNUM);
      store_inferior_registers (FC_REGNUM);
#endif /* ULTRA3 */
    }
}

/* 
 * Fetch an individual register (and supply it).
 * return 0 on success, -1 on failure.
 * NOTE: Assumes AMD's Binary Compatibility Standard for ptrace().
 */
static void
fetch_register (int regno)
{
  char buf[128];
  int val;

  if (CANNOT_FETCH_REGISTER (regno))
    {
      val = -1;
      supply_register (regno, &val);
    }
  else
    {
      errno = 0;
      val = ptrace (PT_READ_U, inferior_pid,
		    (PTRACE_ARG3_TYPE) register_addr (regno, 0), 0);
      if (errno != 0)
	{
	  sprintf (buf, "reading register %s (#%d)", REGISTER_NAME (regno), regno);
	  perror_with_name (buf);
	}
      else
	{
	  supply_register (regno, &val);
	}
    }
}


/* 
 * Read AMD's Binary Compatibilty Standard conforming core file.
 * struct ptrace_user is the first thing in the core file
 *
 * CORE_REG_SECT, CORE_REG_SIZE, WHICH, and REG_ADDR are all ignored.
 */

static void
fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
		      int which, CORE_ADDR reg_addr)
{
  register int regno;
  int val;
  char buf[4];

  for (regno = 0; regno < NUM_REGS; regno++)
    {
      if (!CANNOT_FETCH_REGISTER (regno))
	{
	  val = bfd_seek (core_bfd, (file_ptr) register_addr (regno, 0), SEEK_SET);
	  if (val < 0 || (val = bfd_read (buf, sizeof buf, 1, core_bfd)) < 0)
	    {
	      char *buffer = (char *) alloca (strlen (REGISTER_NAME (regno)) + 35);
	      strcpy (buffer, "Reading core register ");
	      strcat (buffer, REGISTER_NAME (regno));
	      perror_with_name (buffer);
	    }
	  supply_register (regno, buf);
	}
    }

  /* Fake any registers that are in REGISTER_NAMES, but not available to gdb */
  registers_fetched ();
}


/*  
 * Takes a register number as defined in tm.h via REGISTER_NAMES, and maps
 * it to an offset in a struct ptrace_user defined by AMD's BCS.
 * That is, it defines the mapping between gdb register numbers and items in
 * a struct ptrace_user.
 * A register protection scheme is set up here.  If a register not
 * available to the user is specified in 'regno', then an address that
 * will cause ptrace() to fail is returned.
 */
CORE_ADDR
register_addr (int regno, CORE_ADDR blockend)
{
  if ((regno >= LR0_REGNUM) && (regno < LR0_REGNUM + 128))
    {
      return (offsetof (struct ptrace_user, pt_lr[regno - LR0_REGNUM]));
    }
  else if ((regno >= GR96_REGNUM) && (regno < GR96_REGNUM + 32))
    {
      return (offsetof (struct ptrace_user, pt_gr[regno - GR96_REGNUM]));
    }
  else
    {
      switch (regno)
	{
	case GR1_REGNUM:
	  return (offsetof (struct ptrace_user, pt_gr1));
	case CPS_REGNUM:
	  return (offsetof (struct ptrace_user, pt_psr));
	case NPC_REGNUM:
	  return (offsetof (struct ptrace_user, pt_pc0));
	case PC_REGNUM:
	  return (offsetof (struct ptrace_user, pt_pc1));
	case PC2_REGNUM:
	  return (offsetof (struct ptrace_user, pt_pc2));
	case IPC_REGNUM:
	  return (offsetof (struct ptrace_user, pt_ipc));
	case IPA_REGNUM:
	  return (offsetof (struct ptrace_user, pt_ipa));
	case IPB_REGNUM:
	  return (offsetof (struct ptrace_user, pt_ipb));
	case Q_REGNUM:
	  return (offsetof (struct ptrace_user, pt_q));
	case BP_REGNUM:
	  return (offsetof (struct ptrace_user, pt_bp));
	case FC_REGNUM:
	  return (offsetof (struct ptrace_user, pt_fc));
	default:
	  fprintf_filtered (gdb_stderr, "register_addr():Bad register %s (%d)\n",
			    REGISTER_NAME (regno), regno);
	  return (0xffffffff);	/* Should make ptrace() fail */
	}
    }
}


/* Register that we are able to handle ultra3 core file formats.
   FIXME: is this really bfd_target_unknown_flavour? */

static struct core_fns ultra3_core_fns =
{
  bfd_target_unknown_flavour,		/* core_flavour */
  default_check_format,			/* check_format */
  default_core_sniffer,			/* core_sniffer */
  fetch_core_registers,			/* core_read_registers */
  NULL					/* next */
};

void
_initialize_core_ultra3 (void)
{
  add_core_fns (&ultra3_core_fns);
}