[deliverable/binutils-gdb.git] / gdb / hppabsd-xdep.c

/* Machine-dependent code which would otherwise be in infptrace.c,
   for GDB, the GNU debugger.  This code is for the HP PA-RISC cpu.
   Copyright 1986, 1987, 1989, 1990, 1991, 1992 Free Software Foundation, Inc.

   Contributed by the Center for Software Science at the
   University of Utah (pa-gdb-bugs@cs.utah.edu).

/* Low level Unix child interface to ptrace, for GDB when running under Unix.
   Copyright (C) 1988, 1989, 1990, 1991 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "target.h"

#ifdef USG
#include <sys/types.h>
#endif

#include <sys/param.h>
#include <sys/dir.h>
#include <signal.h>
#include <sys/ioctl.h>
#ifndef USG
#include <sys/ptrace.h>
#endif


#ifndef PT_ATTACH
#define PT_ATTACH PTRACE_ATTACH
#endif
#ifndef PT_DETACH
#define PT_DETACH PTRACE_DETACH
#endif

#include "gdbcore.h"
#include <sys/user.h>		/* After a.out.h  */
#include <sys/file.h>
#include <sys/stat.h>
\f
/* This function simply calls ptrace with the given arguments.  
   It exists so that all calls to ptrace are isolated in this 
   machine-dependent file. */
int
call_ptrace (request, pid, addr, data)
     int request, pid;
     PTRACE_ARG3_TYPE addr;
     int data;
{
  return ptrace (request, pid, addr, data);
}

#ifdef DEBUG_PTRACE
/* For the rest of the file, use an extra level of indirection */
/* This lets us breakpoint usefully on call_ptrace. */
#define ptrace call_ptrace
#endif

void
kill_inferior ()
{
  if (inferior_pid == 0)
    return;
  ptrace (PT_KILL, inferior_pid, (PTRACE_ARG3_TYPE) 0, 0);
  wait ((int *)0);
  target_mourn_inferior ();
}

/* Resume execution of the inferior process.
   If STEP is nonzero, single-step it.
   If SIGNAL is nonzero, give it that signal.  */

void
child_resume (step, signal)
     int step;
     int signal;
{
  errno = 0;

  /* An address of (PTRACE_ARG3_TYPE) 1 tells ptrace to continue from where
     it was. (If GDB wanted it to start some other way, we have already
     written a new PC value to the child.)  */

  if (step)
    ptrace (PT_STEP, inferior_pid, (PTRACE_ARG3_TYPE) 1, signal);
  else
    ptrace (PT_CONTINUE, inferior_pid, (PTRACE_ARG3_TYPE) 1, signal);

  if (errno)
    perror_with_name ("ptrace");
}
\f
#ifdef ATTACH_DETACH
/* Nonzero if we are debugging an attached process rather than
   an inferior.  */
extern int attach_flag;

/* Start debugging the process whose number is PID.  */
int
attach (pid)
     int pid;
{
  errno = 0;
  ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 0, 0);
  if (errno)
    perror_with_name ("ptrace");
  attach_flag = 1;
  return pid;
}

/* Stop debugging the process whose number is PID
   and continue it with signal number SIGNAL.
   SIGNAL = 0 means just continue it.  */

void
detach (signal)
     int signal;
{
  errno = 0;
  ptrace (PT_DETACH, inferior_pid, (PTRACE_ARG3_TYPE) 1, signal);
  if (errno)
    perror_with_name ("ptrace");
  attach_flag = 0;
}
#endif /* ATTACH_DETACH */
\f
#if !defined (FETCH_INFERIOR_REGISTERS)

/* KERNEL_U_ADDR is the amount to subtract from u.u_ar0
   to get the offset in the core file of the register values.  */
#if defined (KERNEL_U_ADDR_BSD)
/* Get kernel_u_addr using BSD-style nlist().  */
CORE_ADDR kernel_u_addr;

#include <a.out.gnu.h>		/* For struct nlist */

void
_initialize_kernel_u_addr ()
{
  struct nlist names[2];

  names[0].n_un.n_name = "_u";
  names[1].n_un.n_name = NULL;
  if (nlist ("/vmunix", names) == 0)
    kernel_u_addr = names[0].n_value;
  else
    fatal ("Unable to get kernel u area address.");
}
#endif /* KERNEL_U_ADDR_BSD.  */

#if defined (KERNEL_U_ADDR_HPUX)
/* Get kernel_u_addr using HPUX-style nlist().  */
CORE_ADDR kernel_u_addr;

struct hpnlist {      
        char *          n_name;
        long            n_value;  
        unsigned char   n_type;   
        unsigned char   n_length;  
        short           n_almod;   
        short           n_unused;
};
static struct hpnlist nl[] = {{ "_u", -1, }, { (char *) 0, }};

/* read the value of the u area from the hp-ux kernel */
void _initialize_kernel_u_addr ()
{
    struct user u;
    nlist ("/hp-ux", &nl);
    kernel_u_addr = nl[0].n_value;
}
#endif /* KERNEL_U_ADDR_HPUX.  */

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

/* U_REGS_OFFSET is the offset of the registers within the u area.  */
#if !defined (U_REGS_OFFSET)
#define U_REGS_OFFSET \
  ptrace (PT_READ_U, inferior_pid, \
          (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
    - KERNEL_U_ADDR
#endif

/* Registers we shouldn't try to fetch.  */
#if !defined (CANNOT_FETCH_REGISTER)
#define CANNOT_FETCH_REGISTER(regno) 0
#endif

/* Fetch one register.  */

static void
fetch_register (regno)
     int regno;
{
  register unsigned int regaddr;
  char buf[MAX_REGISTER_RAW_SIZE];
  char mess[128];				/* For messages */
  register int i;

  /* Offset of registers within the u area.  */
  unsigned int offset;

  if (CANNOT_FETCH_REGISTER (regno))
    {
      bzero (buf, REGISTER_RAW_SIZE (regno));	/* Supply zeroes */
      supply_register (regno, buf);
      return;
    }

  offset = U_REGS_OFFSET;

  regaddr = register_addr (regno, offset);
  for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
    {
      errno = 0;
      *(int *) &buf[i] = ptrace (PT_RUREGS, inferior_pid,
				 (PTRACE_ARG3_TYPE) regaddr, 0);
      regaddr += sizeof (int);
      if (errno != 0)
	{
	  sprintf (mess, "reading register %s (#%d)", reg_names[regno], regno);
	  perror_with_name (mess);
	}
    }
  if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
    buf[3] &= ~0x3;
  supply_register (regno, buf);
}


/* Fetch all registers, or just one, from the child process.  */

void
fetch_inferior_registers (regno)
     int regno;
{
  if (regno == -1)
    for (regno = 0; regno < NUM_REGS; regno++)
      fetch_register (regno);
  else
    fetch_register (regno);
}

/* Registers we shouldn't try to store.  */
#if !defined (CANNOT_STORE_REGISTER)
#define CANNOT_STORE_REGISTER(regno) 0
#endif

/* 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).  */

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

  unsigned int offset = U_REGS_OFFSET;

  if (regno >= 0)
    {
      regaddr = register_addr (regno, offset);
      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
	{
	  errno = 0;
	  ptrace (PT_WRITE_U, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
		  *(int *) &registers[REGISTER_BYTE (regno) + i]);
	  if (errno != 0)
	    {
	      sprintf (buf, "writing register number %d(%d)", regno, i);
	      perror_with_name (buf);
	    }
	  regaddr += sizeof(int);
	}
    }
  else
    {
      for (regno = 0; regno < NUM_REGS; regno++)
	{
	  if (CANNOT_STORE_REGISTER (regno))
	    continue;
	  regaddr = register_addr (regno, offset);
	  for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
	    {
	      errno = 0;
	      ptrace (PT_WRITE_U, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
		      *(int *) &registers[REGISTER_BYTE (regno) + i]);
	      if (errno != 0)
		{
		  sprintf (buf, "writing register number %d(%d)", regno, i);
		  perror_with_name (buf);
		}
	      regaddr += sizeof(int);
	    }
	}
    }
  return;
}
#endif /* !defined (FETCH_INFERIOR_REGISTERS).  */
\f
/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
   in the NEW_SUN_PTRACE case.
   It ought to be straightforward.  But it appears that writing did
   not write the data that I specified.  I cannot understand where
   it got the data that it actually did write.  */

/* Copy LEN bytes to or from inferior's memory starting at MEMADDR
   to debugger memory starting at MYADDR.   Copy to inferior if
   WRITE is nonzero.
  
   Returns the length copied, which is either the LEN argument or zero.
   This xfer function does not do partial moves, since child_ops
   doesn't allow memory operations to cross below us in the target stack
   anyway.  */

int
child_xfer_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 = memaddr & - sizeof (int);
  /* Round ending address up; get number of longwords that makes.  */
  register int count
    = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
  /* Allocate buffer of that many longwords.  */
  register 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] = ptrace (PT_READ_I, inferior_pid, (PTRACE_ARG3_TYPE) addr,
			    0);
      }

      if (count > 1)		/* FIXME, avoid if even boundary */
	{
	  buffer[count - 1]
	    = ptrace (PT_READ_I, inferior_pid,
		      (PTRACE_ARG3_TYPE) (addr + (count - 1) * sizeof (int)),
		      0);
	}

      /* 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;
	  ptrace (PT_WRITE_D, inferior_pid, (PTRACE_ARG3_TYPE) addr,
		  buffer[i]);
	  if (errno)
	    {
	      /* Using the appropriate one (I or D) is necessary for
		 Gould NP1, at least.  */
	      errno = 0;
	      ptrace (PT_WRITE_I, inferior_pid, (PTRACE_ARG3_TYPE) 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] = ptrace (PT_READ_I, inferior_pid,
			      (PTRACE_ARG3_TYPE) addr, 0);
	  if (errno)
	    return 0;
	  QUIT;
	}

      /* Copy appropriate bytes out of the buffer.  */
      bcopy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
    }
  return len;
}
Commit	Line	Data
7da1e27d SG	1	/* Machine-dependent code which would otherwise be in infptrace.c,
7da1e27d SG	2	for GDB, the GNU debugger. This code is for the HP PA-RISC cpu.
5140562f	3	Copyright 1986, 1987, 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
7da1e27d SG	4
	5	Contributed by the Center for Software Science at the
	6	University of Utah (pa-gdb-bugs@cs.utah.edu).
	7
	8	/* Low level Unix child interface to ptrace, for GDB when running under Unix.
	9	Copyright (C) 1988, 1989, 1990, 1991 Free Software Foundation, Inc.
	10
	11	This file is part of GDB.
	12
	13	This program is free software; you can redistribute it and/or modify
	14	it under the terms of the GNU General Public License as published by
	15	the Free Software Foundation; either version 2 of the License, or
	16	(at your option) any later version.
	17
	18	This program is distributed in the hope that it will be useful,
	19	but WITHOUT ANY WARRANTY; without even the implied warranty of
	20	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	21	GNU General Public License for more details.
	22
	23	You should have received a copy of the GNU General Public License
	24	along with this program; if not, write to the Free Software
	25	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
	26
7da1e27d SG	27	#include "defs.h"
	28	#include "frame.h"
	29	#include "inferior.h"
	30	#include "target.h"
	31
	32	#ifdef USG
	33	#include <sys/types.h>
	34	#endif
	35
	36	#include <sys/param.h>
	37	#include <sys/dir.h>
	38	#include <signal.h>
	39	#include <sys/ioctl.h>
	40	#ifndef USG
	41	#include <sys/ptrace.h>
	42	#endif
	43
	44
	45	#ifndef PT_ATTACH
	46	#define PT_ATTACH PTRACE_ATTACH
	47	#endif
	48	#ifndef PT_DETACH
	49	#define PT_DETACH PTRACE_DETACH
	50	#endif
	51
	52	#include "gdbcore.h"
	53	#include <sys/user.h> /* After a.out.h */
	54	#include <sys/file.h>
	55	#include <sys/stat.h>
	56	\f
	57	/* This function simply calls ptrace with the given arguments.
	58	It exists so that all calls to ptrace are isolated in this
	59	machine-dependent file. */
	60	int
	61	call_ptrace (request, pid, addr, data)
e676a15f FF	62	int request, pid;
	63	PTRACE_ARG3_TYPE addr;
	64	int data;
7da1e27d SG	65	{
	66	return ptrace (request, pid, addr, data);
	67	}
	68
	69	#ifdef DEBUG_PTRACE
	70	/* For the rest of the file, use an extra level of indirection */
	71	/* This lets us breakpoint usefully on call_ptrace. */
	72	#define ptrace call_ptrace
	73	#endif
	74
7da1e27d	75	void
b28d3617	76	kill_inferior ()
7da1e27d SG	77	{
	78	if (inferior_pid == 0)
	79	return;
e676a15f	80	ptrace (PT_KILL, inferior_pid, (PTRACE_ARG3_TYPE) 0, 0);
7da1e27d	81	wait ((int *)0);
7da1e27d SG	82	target_mourn_inferior ();
	83	}
	84
	85	/* Resume execution of the inferior process.
	86	If STEP is nonzero, single-step it.
	87	If SIGNAL is nonzero, give it that signal. */
	88
	89	void
	90	child_resume (step, signal)
	91	int step;
	92	int signal;
	93	{
	94	errno = 0;
	95
e676a15f FF	96	/* An address of (PTRACE_ARG3_TYPE) 1 tells ptrace to continue from where
	97	it was. (If GDB wanted it to start some other way, we have already
	98	written a new PC value to the child.) */
7da1e27d SG	99
7da1e27d SG	100	if (step)
e676a15f	101	ptrace (PT_STEP, inferior_pid, (PTRACE_ARG3_TYPE) 1, signal);
7da1e27d	102	else
e676a15f	103	ptrace (PT_CONTINUE, inferior_pid, (PTRACE_ARG3_TYPE) 1, signal);
7da1e27d SG	104
	105	if (errno)
	106	perror_with_name ("ptrace");
	107	}
	108	\f
	109	#ifdef ATTACH_DETACH
	110	/* Nonzero if we are debugging an attached process rather than
	111	an inferior. */
	112	extern int attach_flag;
	113
	114	/* Start debugging the process whose number is PID. */
	115	int
	116	attach (pid)
	117	int pid;
	118	{
	119	errno = 0;
e676a15f	120	ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 0, 0);
7da1e27d SG	121	if (errno)
	122	perror_with_name ("ptrace");
	123	attach_flag = 1;
	124	return pid;
	125	}
	126
	127	/* Stop debugging the process whose number is PID
	128	and continue it with signal number SIGNAL.
	129	SIGNAL = 0 means just continue it. */
	130
	131	void
	132	detach (signal)
	133	int signal;
	134	{
	135	errno = 0;
e676a15f	136	ptrace (PT_DETACH, inferior_pid, (PTRACE_ARG3_TYPE) 1, signal);
7da1e27d SG	137	if (errno)
	138	perror_with_name ("ptrace");
	139	attach_flag = 0;
	140	}
	141	#endif /* ATTACH_DETACH */
	142	\f
	143	#if !defined (FETCH_INFERIOR_REGISTERS)
	144
	145	/* KERNEL_U_ADDR is the amount to subtract from u.u_ar0
	146	to get the offset in the core file of the register values. */
	147	#if defined (KERNEL_U_ADDR_BSD)
	148	/* Get kernel_u_addr using BSD-style nlist(). */
	149	CORE_ADDR kernel_u_addr;
	150
	151	#include <a.out.gnu.h> /* For struct nlist */
	152
	153	void
	154	_initialize_kernel_u_addr ()
	155	{
	156	struct nlist names[2];
	157
	158	names[0].n_un.n_name = "_u";
	159	names[1].n_un.n_name = NULL;
	160	if (nlist ("/vmunix", names) == 0)
	161	kernel_u_addr = names[0].n_value;
	162	else
	163	fatal ("Unable to get kernel u area address.");
	164	}
	165	#endif /* KERNEL_U_ADDR_BSD. */
	166
	167	#if defined (KERNEL_U_ADDR_HPUX)
	168	/* Get kernel_u_addr using HPUX-style nlist(). */
	169	CORE_ADDR kernel_u_addr;
	170
	171	struct hpnlist {
	172	char * n_name;
	173	long n_value;
	174	unsigned char n_type;
	175	unsigned char n_length;
	176	short n_almod;
	177	short n_unused;
	178	};
	179	static struct hpnlist nl[] = {{ "_u", -1, }, { (char *) 0, }};
	180
	181	/* read the value of the u area from the hp-ux kernel */
	182	void _initialize_kernel_u_addr ()
	183	{
	184	struct user u;
	185	nlist ("/hp-ux", &nl);
	186	kernel_u_addr = nl[0].n_value;
	187	}
	188	#endif /* KERNEL_U_ADDR_HPUX. */
	189
	190	#if !defined (offsetof)
	191	#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
	192	#endif
	193
	194	/* U_REGS_OFFSET is the offset of the registers within the u area. */
	195	#if !defined (U_REGS_OFFSET)
	196	#define U_REGS_OFFSET \
	197	ptrace (PT_READ_U, inferior_pid, \
e676a15f FF	198	(PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
e676a15f FF	199	- KERNEL_U_ADDR
7da1e27d SG	200	#endif
	201
	202	/* Registers we shouldn't try to fetch. */
	203	#if !defined (CANNOT_FETCH_REGISTER)
	204	#define CANNOT_FETCH_REGISTER(regno) 0
	205	#endif
	206
	207	/* Fetch one register. */
	208
	209	static void
	210	fetch_register (regno)
	211	int regno;
	212	{
	213	register unsigned int regaddr;
	214	char buf[MAX_REGISTER_RAW_SIZE];
	215	char mess[128]; /* For messages */
	216	register int i;
	217
	218	/* Offset of registers within the u area. */
	219	unsigned int offset;
	220
	221	if (CANNOT_FETCH_REGISTER (regno))
	222	{
	223	bzero (buf, REGISTER_RAW_SIZE (regno)); /* Supply zeroes */
	224	supply_register (regno, buf);
	225	return;
	226	}
	227
	228	offset = U_REGS_OFFSET;
	229
	230	regaddr = register_addr (regno, offset);
	231	for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
	232	{
	233	errno = 0;
e676a15f FF	234	(int ) &buf[i] = ptrace (PT_RUREGS, inferior_pid,
e676a15f FF	235	(PTRACE_ARG3_TYPE) regaddr, 0);
7da1e27d SG	236	regaddr += sizeof (int);
	237	if (errno != 0)
	238	{
	239	sprintf (mess, "reading register %s (#%d)", reg_names[regno], regno);
	240	perror_with_name (mess);
	241	}
	242	}
	243	if (regno == PCOQ_HEAD_REGNUM \|\| regno == PCOQ_TAIL_REGNUM)
	244	buf[3] &= ~0x3;
	245	supply_register (regno, buf);
	246	}
	247
	248
	249	/* Fetch all registers, or just one, from the child process. */
	250
	251	void
	252	fetch_inferior_registers (regno)
	253	int regno;
	254	{
	255	if (regno == -1)
	256	for (regno = 0; regno < NUM_REGS; regno++)
	257	fetch_register (regno);
	258	else
	259	fetch_register (regno);
	260	}
	261
	262	/* Registers we shouldn't try to store. */
	263	#if !defined (CANNOT_STORE_REGISTER)
	264	#define CANNOT_STORE_REGISTER(regno) 0
	265	#endif
	266
	267	/* Store our register values back into the inferior.
	268	If REGNO is -1, do this for all registers.
	269	Otherwise, REGNO specifies which register (so we can save time). */
	270
	271	void
	272	store_inferior_registers (regno)
	273	int regno;
	274	{
	275	register unsigned int regaddr;
	276	char buf[80];
	277	extern char registers[];
	278	register int i;
	279
	280	unsigned int offset = U_REGS_OFFSET;
	281
	282	if (regno >= 0)
	283	{
	284	regaddr = register_addr (regno, offset);
	285	for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
	286	{
	287	errno = 0;
e676a15f	288	ptrace (PT_WRITE_U, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
7da1e27d SG	289	(int ) &registers[REGISTER_BYTE (regno) + i]);
	290	if (errno != 0)
	291	{
	292	sprintf (buf, "writing register number %d(%d)", regno, i);
	293	perror_with_name (buf);
	294	}
	295	regaddr += sizeof(int);
	296	}
	297	}
	298	else
	299	{
	300	for (regno = 0; regno < NUM_REGS; regno++)
	301	{
	302	if (CANNOT_STORE_REGISTER (regno))
	303	continue;
	304	regaddr = register_addr (regno, offset);
	305	for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
	306	{
	307	errno = 0;
e676a15f	308	ptrace (PT_WRITE_U, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
7da1e27d SG	309	(int ) &registers[REGISTER_BYTE (regno) + i]);
	310	if (errno != 0)
	311	{
	312	sprintf (buf, "writing register number %d(%d)", regno, i);
	313	perror_with_name (buf);
	314	}
	315	regaddr += sizeof(int);
	316	}
	317	}
	318	}
	319	return;
	320	}
	321	#endif /* !defined (FETCH_INFERIOR_REGISTERS). */
	322	\f
	323	/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
	324	in the NEW_SUN_PTRACE case.
	325	It ought to be straightforward. But it appears that writing did
	326	not write the data that I specified. I cannot understand where
	327	it got the data that it actually did write. */
	328
	329	/* Copy LEN bytes to or from inferior's memory starting at MEMADDR
	330	to debugger memory starting at MYADDR. Copy to inferior if
	331	WRITE is nonzero.
	332
	333	Returns the length copied, which is either the LEN argument or zero.
	334	This xfer function does not do partial moves, since child_ops
	335	doesn't allow memory operations to cross below us in the target stack
	336	anyway. */
	337
	338	int
	339	child_xfer_memory (memaddr, myaddr, len, write, target)
	340	CORE_ADDR memaddr;
	341	char *myaddr;
	342	int len;
	343	int write;
	344	struct target_ops target; / ignored */
	345	{
	346	register int i;
	347	/* Round starting address down to longword boundary. */
	348	register CORE_ADDR addr = memaddr & - sizeof (int);
	349	/* Round ending address up; get number of longwords that makes. */
	350	register int count
	351	= (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
	352	/* Allocate buffer of that many longwords. */
	353	register int buffer = (int ) alloca (count * sizeof (int));
	354
	355	if (write)
	356	{
	357	/* Fill start and end extra bytes of buffer with existing memory data. */
	358
	359	if (addr != memaddr \|\| len < (int)sizeof (int)) {
	360	/* Need part of initial word -- fetch it. */
e676a15f FF	361	buffer[0] = ptrace (PT_READ_I, inferior_pid, (PTRACE_ARG3_TYPE) addr,
e676a15f FF	362	0);
7da1e27d SG	363	}
	364
	365	if (count > 1) /* FIXME, avoid if even boundary */
	366	{
	367	buffer[count - 1]
	368	= ptrace (PT_READ_I, inferior_pid,
e676a15f FF	369	(PTRACE_ARG3_TYPE) (addr + (count - 1) * sizeof (int)),
e676a15f FF	370	0);
7da1e27d SG	371	}
	372
	373	/* Copy data to be written over corresponding part of buffer */
	374
	375	bcopy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
	376
	377	/* Write the entire buffer. */
	378
	379	for (i = 0; i < count; i++, addr += sizeof (int))
	380	{
	381	errno = 0;
e676a15f FF	382	ptrace (PT_WRITE_D, inferior_pid, (PTRACE_ARG3_TYPE) addr,
e676a15f FF	383	buffer[i]);
7da1e27d SG	384	if (errno)
	385	{
	386	/* Using the appropriate one (I or D) is necessary for
	387	Gould NP1, at least. */
	388	errno = 0;
e676a15f FF	389	ptrace (PT_WRITE_I, inferior_pid, (PTRACE_ARG3_TYPE) addr,
e676a15f FF	390	buffer[i]);
7da1e27d SG	391	}
	392	if (errno)
	393	return 0;
	394	}
	395	}
	396	else
	397	{
	398	/* Read all the longwords */
	399	for (i = 0; i < count; i++, addr += sizeof (int))
	400	{
	401	errno = 0;
e676a15f FF	402	buffer[i] = ptrace (PT_READ_I, inferior_pid,
e676a15f FF	403	(PTRACE_ARG3_TYPE) addr, 0);
7da1e27d SG	404	if (errno)
	405	return 0;
	406	QUIT;
	407	}
	408
	409	/* Copy appropriate bytes out of the buffer. */
	410	bcopy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
	411	}
	412	return len;
	413	}