[thirdparty/binutils-gdb.git] / gdb / gdbserver / linux-low.c

/* Low level interface to ptrace, for the remote server for GDB.
   Copyright 1995, 1996, 1998, 1999, 2000, 2001, 2002
   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 <sys/wait.h>
#include <stdio.h>
#include <sys/param.h>
#include <sys/dir.h>
#include <sys/ptrace.h>
#include <sys/user.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>

#define PTRACE_ARG3_TYPE long
#define PTRACE_XFER_TYPE long

#ifdef HAVE_LINUX_REGSETS
static int use_regsets_p = 1;
#endif

extern int errno;

#ifdef HAVE_LINUX_USRREGS
extern int num_regs;
extern int regmap[];
#endif

/* Start an inferior process and returns its pid.
   ALLARGS is a vector of program-name and args. */

int
create_inferior (char *program, char **allargs)
{
  int pid;

  pid = fork ();
  if (pid < 0)
    perror_with_name ("fork");

  if (pid == 0)
    {
      ptrace (PTRACE_TRACEME, 0, 0, 0);

      execv (program, allargs);

      fprintf (stderr, "Cannot exec %s: %s.\n", program,
	       strerror (errno));
      fflush (stderr);
      _exit (0177);
    }

  return pid;
}

/* Attach to an inferior process.  */

int
myattach (int pid)
{
  if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0)
    {
      fprintf (stderr, "Cannot attach to process %d: %s (%d)\n", pid,
	       errno < sys_nerr ? sys_errlist[errno] : "unknown error",
	       errno);
      fflush (stderr);
      _exit (0177);
    }

  return 0;
}

/* Kill the inferior process.  Make us have no inferior.  */

void
kill_inferior (void)
{
  if (inferior_pid == 0)
    return;
  ptrace (PTRACE_KILL, inferior_pid, 0, 0);
  wait (0);
}

/* Return nonzero if the given thread is still alive.  */
int
mythread_alive (int pid)
{
  return 1;
}

/* Wait for process, returns status */

unsigned char
mywait (char *status)
{
  int pid;
  int w;

  enable_async_io ();
  pid = waitpid (inferior_pid, &w, 0);
  disable_async_io ();
  if (pid != inferior_pid)
    perror_with_name ("wait");

  if (WIFEXITED (w))
    {
      fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
      *status = 'W';
      return ((unsigned char) WEXITSTATUS (w));
    }
  else if (!WIFSTOPPED (w))
    {
      fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
      *status = 'X';
      return ((unsigned char) WTERMSIG (w));
    }

  fetch_inferior_registers (0);

  *status = 'T';
  return ((unsigned char) WSTOPSIG (w));
}

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

void
myresume (int step, int signal)
{
  errno = 0;
  ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, inferior_pid, 1, signal);
  if (errno)
    perror_with_name ("ptrace");
}


#ifdef HAVE_LINUX_USRREGS

#define REGISTER_RAW_SIZE(regno) register_size((regno))

int
register_addr (int regnum)
{
  int addr;

  if (regnum < 0 || regnum >= num_regs)
    error ("Invalid register number %d.", regnum);

  addr = regmap[regnum];
  if (addr == -1)
    addr = 0;

  return addr;
}

/* Fetch one register.  */
static void
fetch_register (int regno)
{
  CORE_ADDR regaddr;
  register int i;

  if (regno >= num_regs)
    return;
  if (cannot_fetch_register (regno))
    return;

  regaddr = register_addr (regno);
  if (regaddr == -1)
    return;
  for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
    {
      errno = 0;
      *(PTRACE_XFER_TYPE *) (register_data (regno) + i) =
	ptrace (PTRACE_PEEKUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, 0);
      regaddr += sizeof (PTRACE_XFER_TYPE);
      if (errno != 0)
	{
	  /* Warning, not error, in case we are attached; sometimes the
	     kernel doesn't let us at the registers.  */
	  char *err = strerror (errno);
	  char *msg = alloca (strlen (err) + 128);
	  sprintf (msg, "reading register %d: %s", regno, err);
	  error (msg);
	  goto error_exit;
	}
    }
error_exit:;
}

/* Fetch all registers, or just one, from the child process.  */
static void
usr_fetch_inferior_registers (int regno)
{
  if (regno == -1 || regno == 0)
    for (regno = 0; regno < num_regs; regno++)
      fetch_register (regno);
  else
    fetch_register (regno);
}

/* 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).  */
static void
usr_store_inferior_registers (int regno)
{
  CORE_ADDR regaddr;
  int i;

  if (regno >= 0)
    {
      if (regno >= num_regs)
	return;

      if (cannot_store_register (regno))
	return;

      regaddr = register_addr (regno);
      if (regaddr == -1)
	return;
      errno = 0;
      for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
	{
	  errno = 0;
	  ptrace (PTRACE_POKEUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
		  *(int *) (register_data (regno) + i));
	  if (errno != 0)
	    {
	      /* Warning, not error, in case we are attached; sometimes the
		 kernel doesn't let us at the registers.  */
	      char *err = strerror (errno);
	      char *msg = alloca (strlen (err) + 128);
	      sprintf (msg, "writing register %d: %s",
		       regno, err);
	      error (msg);
	      return;
	    }
	  regaddr += sizeof (int);
	}
    }
  else
    for (regno = 0; regno < num_regs; regno++)
      store_inferior_registers (regno);
}
#endif /* HAVE_LINUX_USRREGS */


#ifdef HAVE_LINUX_REGSETS

static int
regsets_fetch_inferior_registers (void)
{
  struct regset_info *regset;

  regset = target_regsets;

  while (regset->size >= 0)
    {
      void *buf;
      int res;

      if (regset->size == 0)
	{
	  regset ++;
	  continue;
	}

      buf = malloc (regset->size);
      res = ptrace (regset->get_request, inferior_pid, 0, (int) buf);
      if (res < 0)
	{
	  if (errno == EIO)
	    {
	      /* If we get EIO on the first regset, do not try regsets again.
		 If we get EIO on a later regset, disable that regset.  */
	      if (regset == target_regsets)
		{
		  use_regsets_p = 0;
		  return -1;
		}
	      else
		{
		  regset->size = 0;
		  continue;
		}
	    }
	  else
	    {
	      perror ("Warning: ptrace(regsets_fetch_inferior_registers)");
	    }
	}
      regset->store_function (buf);
      regset ++;
    }
}

static int
regsets_store_inferior_registers (void)
{
  struct regset_info *regset;

  regset = target_regsets;

  while (regset->size >= 0)
    {
      void *buf;
      int res;

      if (regset->size == 0)
	{
	  regset ++;
	  continue;
	}

      buf = malloc (regset->size);
      regset->fill_function (buf);
      res = ptrace (regset->set_request, inferior_pid, 0, (int) buf);
      if (res < 0)
	{
	  if (errno == EIO)
	    {
	      /* If we get EIO on the first regset, do not try regsets again.
		 If we get EIO on a later regset, disable that regset.  */
	      if (regset == target_regsets)
		{
		  use_regsets_p = 0;
		  return -1;
		}
	      else
		{
		  regset->size = 0;
		  continue;
		}
	    }
	  else
	    {
	      perror ("Warning: ptrace(regsets_fetch_inferior_registers)");
	    }
	}
      regset ++;
    }
}

#endif /* HAVE_LINUX_REGSETS */


void
fetch_inferior_registers (int regno)
{
#ifdef HAVE_LINUX_REGSETS
  if (use_regsets_p)
    {
      if (regsets_fetch_inferior_registers () == 0)
	return;
    }
#endif
#ifdef HAVE_LINUX_USRREGS
  usr_fetch_inferior_registers (regno);
#endif
}

void
store_inferior_registers (int regno)
{
#ifdef HAVE_LINUX_REGSETS
  if (use_regsets_p)
    {
      if (regsets_store_inferior_registers () == 0)
	return;
    }
#endif
#ifdef HAVE_LINUX_USRREGS
  usr_store_inferior_registers (regno);
#endif
}


/* Copy LEN bytes from inferior's memory starting at MEMADDR
   to debugger memory starting at MYADDR.  */

void
read_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
{
  register int i;
  /* Round starting address down to longword boundary.  */
  register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
  /* Round ending address up; get number of longwords that makes.  */
  register int count 
    = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) 
      / sizeof (PTRACE_XFER_TYPE);
  /* Allocate buffer of that many longwords.  */
  register PTRACE_XFER_TYPE *buffer 
    = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));

  /* Read all the longwords */
  for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
    {
      buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, 0);
    }

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

/* Copy LEN bytes of data from debugger memory at MYADDR
   to inferior's memory at MEMADDR.
   On failure (cannot write the inferior)
   returns the value of errno.  */

int
write_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
{
  register int i;
  /* Round starting address down to longword boundary.  */
  register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
  /* Round ending address up; get number of longwords that makes.  */
  register int count
  = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) / sizeof (PTRACE_XFER_TYPE);
  /* Allocate buffer of that many longwords.  */
  register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
  extern int errno;

  /* Fill start and end extra bytes of buffer with existing memory data.  */

  buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid,
		      (PTRACE_ARG3_TYPE) addr, 0);

  if (count > 1)
    {
      buffer[count - 1]
	= ptrace (PTRACE_PEEKTEXT, inferior_pid,
		  (PTRACE_ARG3_TYPE) (addr + (count - 1)
				      * sizeof (PTRACE_XFER_TYPE)),
		  0);
    }

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

  memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), myaddr, len);

  /* Write the entire buffer.  */

  for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
    {
      errno = 0;
      ptrace (PTRACE_POKETEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, buffer[i]);
      if (errno)
	return errno;
    }

  return 0;
}
\f
void
initialize_low (void)
{
  init_registers ();
}
Commit	Line	Data
da6d8c04 DJ	1	/* Low level interface to ptrace, for the remote server for GDB.
	2	Copyright 1995, 1996, 1998, 1999, 2000, 2001, 2002
	3	Free Software Foundation, Inc.
	4
	5	This file is part of GDB.
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 2 of the License, or
	10	(at your option) any later version.
	11
	12	This program is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with this program; if not, write to the Free Software
	19	Foundation, Inc., 59 Temple Place - Suite 330,
	20	Boston, MA 02111-1307, USA. */
	21
	22	#include "server.h"
58caa3dc	23	#include "linux-low.h"
da6d8c04	24
58caa3dc	25	#include <sys/wait.h>
da6d8c04 DJ	26	#include <stdio.h>
	27	#include <sys/param.h>
	28	#include <sys/dir.h>
	29	#include <sys/ptrace.h>
	30	#include <sys/user.h>
	31	#include <signal.h>
	32	#include <sys/ioctl.h>
	33	#include <fcntl.h>
d07c63e7	34	#include <string.h>
0a30fbc4 DJ	35	#include <stdlib.h>
0a30fbc4 DJ	36	#include <unistd.h>
da6d8c04	37
d844cde6	38	#define PTRACE_ARG3_TYPE long
c6ecbae5	39	#define PTRACE_XFER_TYPE long
da6d8c04	40
58caa3dc DJ	41	#ifdef HAVE_LINUX_REGSETS
	42	static int use_regsets_p = 1;
	43	#endif
	44
da6d8c04	45	extern int errno;
c6ecbae5 DJ	46
c6ecbae5 DJ	47	#ifdef HAVE_LINUX_USRREGS
0a30fbc4 DJ	48	extern int num_regs;
0a30fbc4 DJ	49	extern int regmap[];
c6ecbae5	50	#endif
da6d8c04 DJ	51
	52	/* Start an inferior process and returns its pid.
	53	ALLARGS is a vector of program-name and args. */
	54
	55	int
	56	create_inferior (char program, char *allargs)
	57	{
	58	int pid;
	59
	60	pid = fork ();
	61	if (pid < 0)
	62	perror_with_name ("fork");
	63
	64	if (pid == 0)
	65	{
	66	ptrace (PTRACE_TRACEME, 0, 0, 0);
	67
	68	execv (program, allargs);
	69
	70	fprintf (stderr, "Cannot exec %s: %s.\n", program,
d07c63e7	71	strerror (errno));
da6d8c04 DJ	72	fflush (stderr);
	73	_exit (0177);
	74	}
	75
	76	return pid;
	77	}
	78
	79	/* Attach to an inferior process. */
	80
	81	int
	82	myattach (int pid)
	83	{
	84	if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0)
	85	{
	86	fprintf (stderr, "Cannot attach to process %d: %s (%d)\n", pid,
	87	errno < sys_nerr ? sys_errlist[errno] : "unknown error",
	88	errno);
	89	fflush (stderr);
	90	_exit (0177);
	91	}
	92
	93	return 0;
	94	}
	95
	96	/* Kill the inferior process. Make us have no inferior. */
	97
	98	void
	99	kill_inferior (void)
	100	{
	101	if (inferior_pid == 0)
	102	return;
	103	ptrace (PTRACE_KILL, inferior_pid, 0, 0);
	104	wait (0);
da6d8c04 DJ	105	}
	106
	107	/* Return nonzero if the given thread is still alive. */
	108	int
	109	mythread_alive (int pid)
	110	{
	111	return 1;
	112	}
	113
	114	/* Wait for process, returns status */
	115
	116	unsigned char
	117	mywait (char *status)
	118	{
	119	int pid;
e5f1222d	120	int w;
da6d8c04 DJ	121
da6d8c04 DJ	122	enable_async_io ();
e5f1222d	123	pid = waitpid (inferior_pid, &w, 0);
da6d8c04 DJ	124	disable_async_io ();
	125	if (pid != inferior_pid)
	126	perror_with_name ("wait");
	127
	128	if (WIFEXITED (w))
	129	{
	130	fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
	131	*status = 'W';
	132	return ((unsigned char) WEXITSTATUS (w));
	133	}
	134	else if (!WIFSTOPPED (w))
	135	{
	136	fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
	137	*status = 'X';
	138	return ((unsigned char) WTERMSIG (w));
	139	}
	140
	141	fetch_inferior_registers (0);
	142
	143	*status = 'T';
	144	return ((unsigned char) WSTOPSIG (w));
	145	}
	146
	147	/* Resume execution of the inferior process.
	148	If STEP is nonzero, single-step it.
	149	If SIGNAL is nonzero, give it that signal. */
	150
	151	void
	152	myresume (int step, int signal)
	153	{
	154	errno = 0;
	155	ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, inferior_pid, 1, signal);
	156	if (errno)
	157	perror_with_name ("ptrace");
	158	}
	159
c6ecbae5 DJ	160
	161	#ifdef HAVE_LINUX_USRREGS
	162
0a30fbc4	163	#define REGISTER_RAW_SIZE(regno) register_size((regno))
da6d8c04 DJ	164
da6d8c04 DJ	165	int
0a30fbc4	166	register_addr (int regnum)
da6d8c04 DJ	167	{
	168	int addr;
	169
0a30fbc4	170	if (regnum < 0 \|\| regnum >= num_regs)
da6d8c04 DJ	171	error ("Invalid register number %d.", regnum);
da6d8c04 DJ	172
0a30fbc4	173	addr = regmap[regnum];
da6d8c04 DJ	174	if (addr == -1)
	175	addr = 0;
	176
	177	return addr;
	178	}
	179
58caa3dc	180	/* Fetch one register. */
da6d8c04 DJ	181	static void
	182	fetch_register (int regno)
	183	{
	184	CORE_ADDR regaddr;
	185	register int i;
	186
0a30fbc4 DJ	187	if (regno >= num_regs)
	188	return;
	189	if (cannot_fetch_register (regno))
	190	return;
da6d8c04	191
0a30fbc4 DJ	192	regaddr = register_addr (regno);
	193	if (regaddr == -1)
	194	return;
da6d8c04 DJ	195	for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
	196	{
	197	errno = 0;
0a30fbc4	198	(PTRACE_XFER_TYPE ) (register_data (regno) + i) =
da6d8c04 DJ	199	ptrace (PTRACE_PEEKUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr, 0);
	200	regaddr += sizeof (PTRACE_XFER_TYPE);
	201	if (errno != 0)
	202	{
	203	/* Warning, not error, in case we are attached; sometimes the
	204	kernel doesn't let us at the registers. */
	205	char *err = strerror (errno);
	206	char *msg = alloca (strlen (err) + 128);
	207	sprintf (msg, "reading register %d: %s", regno, err);
	208	error (msg);
	209	goto error_exit;
	210	}
	211	}
	212	error_exit:;
	213	}
	214
	215	/* Fetch all registers, or just one, from the child process. */
58caa3dc DJ	216	static void
58caa3dc DJ	217	usr_fetch_inferior_registers (int regno)
da6d8c04 DJ	218	{
da6d8c04 DJ	219	if (regno == -1 \|\| regno == 0)
0a30fbc4	220	for (regno = 0; regno < num_regs; regno++)
da6d8c04 DJ	221	fetch_register (regno);
	222	else
	223	fetch_register (regno);
	224	}
	225
	226	/* Store our register values back into the inferior.
	227	If REGNO is -1, do this for all registers.
	228	Otherwise, REGNO specifies which register (so we can save time). */
58caa3dc DJ	229	static void
58caa3dc DJ	230	usr_store_inferior_registers (int regno)
da6d8c04 DJ	231	{
	232	CORE_ADDR regaddr;
	233	int i;
da6d8c04 DJ	234
	235	if (regno >= 0)
	236	{
0a30fbc4 DJ	237	if (regno >= num_regs)
	238	return;
	239
	240	if (cannot_store_register (regno))
	241	return;
	242
	243	regaddr = register_addr (regno);
	244	if (regaddr == -1)
da6d8c04	245	return;
da6d8c04	246	errno = 0;
c6ecbae5	247	for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (PTRACE_XFER_TYPE))
da6d8c04	248	{
0a30fbc4 DJ	249	errno = 0;
	250	ptrace (PTRACE_POKEUSER, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
	251	(int ) (register_data (regno) + i));
da6d8c04 DJ	252	if (errno != 0)
da6d8c04 DJ	253	{
0a30fbc4 DJ	254	/* Warning, not error, in case we are attached; sometimes the
	255	kernel doesn't let us at the registers. */
	256	char *err = strerror (errno);
	257	char *msg = alloca (strlen (err) + 128);
	258	sprintf (msg, "writing register %d: %s",
	259	regno, err);
	260	error (msg);
	261	return;
da6d8c04	262	}
0a30fbc4	263	regaddr += sizeof (int);
da6d8c04	264	}
da6d8c04 DJ	265	}
da6d8c04 DJ	266	else
0a30fbc4	267	for (regno = 0; regno < num_regs; regno++)
da6d8c04 DJ	268	store_inferior_registers (regno);
da6d8c04 DJ	269	}
58caa3dc DJ	270	#endif /* HAVE_LINUX_USRREGS */
	271
	272
	273
	274	#ifdef HAVE_LINUX_REGSETS
	275
	276	static int
	277	regsets_fetch_inferior_registers (void)
	278	{
	279	struct regset_info *regset;
	280
	281	regset = target_regsets;
	282
	283	while (regset->size >= 0)
	284	{
	285	void *buf;
	286	int res;
	287
	288	if (regset->size == 0)
	289	{
	290	regset ++;
	291	continue;
	292	}
	293
	294	buf = malloc (regset->size);
	295	res = ptrace (regset->get_request, inferior_pid, 0, (int) buf);
	296	if (res < 0)
	297	{
	298	if (errno == EIO)
	299	{
	300	/* If we get EIO on the first regset, do not try regsets again.
	301	If we get EIO on a later regset, disable that regset. */
	302	if (regset == target_regsets)
	303	{
	304	use_regsets_p = 0;
	305	return -1;
	306	}
	307	else
	308	{
	309	regset->size = 0;
	310	continue;
	311	}
	312	}
	313	else
	314	{
	315	perror ("Warning: ptrace(regsets_fetch_inferior_registers)");
	316	}
	317	}
	318	regset->store_function (buf);
	319	regset ++;
	320	}
	321	}
	322
	323	static int
	324	regsets_store_inferior_registers (void)
	325	{
	326	struct regset_info *regset;
	327
	328	regset = target_regsets;
	329
	330	while (regset->size >= 0)
	331	{
	332	void *buf;
	333	int res;
334
335	if (regset->size == 0)
336	{
337	regset ++;
338	continue;
339	}
340
341	buf = malloc (regset->size);
342	regset->fill_function (buf);
343	res = ptrace (regset->set_request, inferior_pid, 0, (int) buf);
344	if (res < 0)
345	{
346	if (errno == EIO)
347	{
348	/* If we get EIO on the first regset, do not try regsets again.
349	If we get EIO on a later regset, disable that regset. */
350	if (regset == target_regsets)
351	{
352	use_regsets_p = 0;
353	return -1;
354	}
355	else
356	{
357	regset->size = 0;
358	continue;
359	}
360	}
361	else
362	{
363	perror ("Warning: ptrace(regsets_fetch_inferior_registers)");
364	}
365	}
366	regset ++;
367	}
368	}
369
370	#endif /* HAVE_LINUX_REGSETS */
371
372
373	void
374	fetch_inferior_registers (int regno)
375	{
376	#ifdef HAVE_LINUX_REGSETS
377	if (use_regsets_p)
378	{
379	if (regsets_fetch_inferior_registers () == 0)
380	return;
381	}
382	#endif
383	#ifdef HAVE_LINUX_USRREGS
384	usr_fetch_inferior_registers (regno);
385	#endif
386	}
387
388	void
389	store_inferior_registers (int regno)
390	{
391	#ifdef HAVE_LINUX_REGSETS
392	if (use_regsets_p)
393	{
394	if (regsets_store_inferior_registers () == 0)
395	return;
396	}
397	#endif
398	#ifdef HAVE_LINUX_USRREGS
399	usr_store_inferior_registers (regno);
400	#endif
401	}
402
da6d8c04	403
da6d8c04 DJ	404	/* Copy LEN bytes from inferior's memory starting at MEMADDR
	405	to debugger memory starting at MYADDR. */
	406
	407	void
	408	read_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
	409	{
	410	register int i;
	411	/* Round starting address down to longword boundary. */
	412	register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
	413	/* Round ending address up; get number of longwords that makes. */
	414	register int count
	415	= (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
	416	/ sizeof (PTRACE_XFER_TYPE);
	417	/* Allocate buffer of that many longwords. */
	418	register PTRACE_XFER_TYPE *buffer
	419	= (PTRACE_XFER_TYPE ) alloca (count sizeof (PTRACE_XFER_TYPE));
	420
	421	/* Read all the longwords */
	422	for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
	423	{
d844cde6	424	buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, 0);
da6d8c04 DJ	425	}
	426
	427	/* Copy appropriate bytes out of the buffer. */
	428	memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), len);
	429	}
	430
	431	/* Copy LEN bytes of data from debugger memory at MYADDR
	432	to inferior's memory at MEMADDR.
	433	On failure (cannot write the inferior)
	434	returns the value of errno. */
	435
	436	int
	437	write_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
	438	{
	439	register int i;
	440	/* Round starting address down to longword boundary. */
	441	register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
	442	/* Round ending address up; get number of longwords that makes. */
	443	register int count
	444	= (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1) / sizeof (PTRACE_XFER_TYPE);
	445	/* Allocate buffer of that many longwords. */
	446	register PTRACE_XFER_TYPE buffer = (PTRACE_XFER_TYPE ) alloca (count * sizeof (PTRACE_XFER_TYPE));
	447	extern int errno;
	448
	449	/* Fill start and end extra bytes of buffer with existing memory data. */
	450
d844cde6 DJ	451	buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid,
d844cde6 DJ	452	(PTRACE_ARG3_TYPE) addr, 0);
da6d8c04 DJ	453
	454	if (count > 1)
	455	{
	456	buffer[count - 1]
	457	= ptrace (PTRACE_PEEKTEXT, inferior_pid,
d844cde6 DJ	458	(PTRACE_ARG3_TYPE) (addr + (count - 1)
	459	* sizeof (PTRACE_XFER_TYPE)),
	460	0);
da6d8c04 DJ	461	}
	462
	463	/* Copy data to be written over corresponding part of buffer */
	464
	465	memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)), myaddr, len);
	466
	467	/* Write the entire buffer. */
	468
	469	for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
	470	{
	471	errno = 0;
d844cde6	472	ptrace (PTRACE_POKETEXT, inferior_pid, (PTRACE_ARG3_TYPE) addr, buffer[i]);
da6d8c04 DJ	473	if (errno)
	474	return errno;
	475	}
	476
	477	return 0;
	478	}
	479	\f
	480	void
	481	initialize_low (void)
	482	{
0a30fbc4	483	init_registers ();
da6d8c04	484	}