binutils-gdb/gdb/core-regset.c

/* Machine independent GDB support for core files on systems using "regsets".

   Copyright (C) 1993-2017 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 3 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, see <http://www.gnu.org/licenses/>.  */

/* This file is used by most systems that use ELF for their core
   dumps.  This includes most systems that have SVR4-ish variant of
   /proc.  For these systems, the registers are laid out the same way
   in core files as in the gregset_t and fpregset_t structures that
   are used in the interaction with /proc (Irix 4 is an exception and
   therefore doesn't use this file).  Quite a few systems without a
   SVR4-ish /proc define these structures too, and can make use of
   this code too.  */

#include "defs.h"
#include "command.h"
#include "gdbcore.h"
#include "inferior.h"
#include "target.h"
#include "regcache.h"

#include <fcntl.h>
#include <time.h>
#ifdef HAVE_SYS_PROCFS_H
#include <sys/procfs.h>
#endif

/* Prototypes for supply_gregset etc.  */
#include "gregset.h"

/* Provide registers to GDB from a core file.

   CORE_REG_SECT points to an array of bytes, which are the contents
   of a `note' from a core file which BFD thinks might contain
   register contents.  CORE_REG_SIZE is its size.

   WHICH says which register set corelow suspects this is:
     0 --- the general-purpose register set, in gregset_t format
     2 --- the floating-point register set, in fpregset_t format

   REG_ADDR is ignored.  */

static void
fetch_core_registers (struct regcache *regcache,
		      char *core_reg_sect,
		      unsigned core_reg_size,
		      int which,
		      CORE_ADDR reg_addr)
{
  gdb_gregset_t gregset;
  gdb_fpregset_t fpregset;
  gdb_gregset_t *gregset_p = &gregset;
  gdb_fpregset_t *fpregset_p = &fpregset;

  switch (which)
    {
    case 0:
      if (core_reg_size != sizeof (gregset))
	warning (_("Wrong size gregset in core file."));
      else
	{
	  memcpy (&gregset, core_reg_sect, sizeof (gregset));
	  supply_gregset (regcache, (const gdb_gregset_t *) gregset_p);
	}
      break;

    case 2:
      if (core_reg_size != sizeof (fpregset))
	warning (_("Wrong size fpregset in core file."));
      else
	{
	  memcpy (&fpregset, core_reg_sect, sizeof (fpregset));
	  if (gdbarch_fp0_regnum (regcache->arch ()) >= 0)
	    supply_fpregset (regcache,
			     (const gdb_fpregset_t *) fpregset_p);
	}
      break;

    default:
      /* We've covered all the kinds of registers we know about here,
         so this must be something we wouldn't know what to do with
         anyway.  Just ignore it.  */
      break;
    }
}


/* Register that we are able to handle ELF core file formats using
   standard procfs "regset" structures.  */

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

void
_initialize_core_regset (void)
{
  deprecated_add_core_fns (&regset_core_fns);
}