/* Host-dependent code for GDB, for NYU Ultra3 running Sym1 OS.
   Copyright (C) 1988, 1989, 1991 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#define DEBUG
#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "symtab.h"
#include "value.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 <sys/stat.h>
#include <sys/ptrace.h>

/* 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;

/* 
 * 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 (regno)
     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)",reg_names[regno],regno);
      perror_with_name (buf);
    } else {
      supply_register (regno, &val);
    }
  }
}

/* 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 (regno)
  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 (regno)
     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)", reg_names[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 */
    }
}

/* 
 * Read AMD's Binary Compatibilty Standard conforming core file.
 * struct ptrace_user is the first thing in the core file
 */

void
fetch_core_registers ()
{
  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, register_addr (regno, 0), 0);
      if (val < 0 || (val = bfd_read (buf, sizeof buf, 1, core_bfd)) < 0) {
        char * buffer = (char *) alloca (strlen (reg_names[regno]) + 35);
        strcpy (buffer, "Reading core register ");
        strcat (buffer, reg_names[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.
 */
unsigned int 
register_addr (regno,blockend)
     unsigned int	regno;
     char		*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(stderr,"register_addr():Bad register %s (%d)\n", 
				reg_names[regno],regno);
	     return(0xffffffff);	/* Should make ptrace() fail */
    }
  }
}


/* Assorted operating system circumventions */

#ifdef SYM1

/* FIXME: Kludge this for now. It really should be system call. */
int
getpagesize()
{ return(8192); }

/* FIXME: Fake out the fcntl() call, which we don't have.  */
fcntl(fd, cmd, arg)
int fd, cmd, arg;
{

  switch (cmd) {
	case F_GETFL: return(O_RDONLY);	break;
	default:	
		printf("Ultra3's fcntl() failing, cmd = %d.\n",cmd);
		return(-1);
  }
}


/* 
 * 4.2 Signal support, requires linking with libjobs.
 */
static int	_SigMask;
#define sigbit(s)       (1L << ((s)-1))

init_SigMask()
{
	/* Taken from the sym1 kernel in machdep.c:startup() */
	_SigMask = sigbit (SIGTSTP) | sigbit (SIGTTOU) | sigbit (SIGTTIN) |
                        sigbit (SIGCHLD) | sigbit (SIGTINT);
}

sigmask(signo)
	int signo;
{
	return (1 << (signo-1));
}

sigsetmask(sigmask)
unsigned int sigmask;
{
	int i, mask = 1;
	int lastmask = _SigMask;

	for (i=0 ; i<NSIG ; i++) {
		if (sigmask & mask) { 
			if (!(_SigMask & mask)) {
				sighold(i+1);
				_SigMask |= mask;
			}
		} else if (_SigMask & mask) {
			sigrelse(i+1);
			_SigMask &= ~mask;
		}
		mask <<= 1;
	}
	return (lastmask);
}

sigblock(sigmask)
unsigned int sigmask;
{
	int i, mask = 1;
	int lastmask = _SigMask;

	for (i=0 ; i<NSIG ; i++) {
		if ((sigmask & mask) && !(_SigMask & mask)) {
			sighold(i+1);
			_SigMask |= mask;
		}
		mask <<= 1;
	}
	return (lastmask);
}
#endif /* SYM1 */


/* Initialization code for this module.  */

_initialize_ultra3 ()
{
#ifdef SYM1
	init_SigMask();
#endif
}