binutils-gdb/gdb/frame-base.c

/* Definitions for frame address handler, for GDB, the GNU debugger.

   Copyright (C) 2003, 2004, 2007, 2008 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/>.  */

#include "defs.h"
#include "frame-base.h"
#include "frame.h"
#include "gdb_obstack.h"

/* A default frame base implementations.  If it wasn't for the old
   DEPRECATED_FRAME_LOCALS_ADDRESS and DEPRECATED_FRAME_ARGS_ADDRESS,
   these could be combined into a single function.  All architectures
   really need to override this.  */

static CORE_ADDR
default_frame_base_address (struct frame_info *next_frame, void **this_cache)
{
  struct frame_info *this_frame = get_prev_frame (next_frame);
  return get_frame_base (this_frame); /* sigh! */
}

static CORE_ADDR
default_frame_locals_address (struct frame_info *next_frame, void **this_cache)
{
  return default_frame_base_address (next_frame, this_cache);
}

static CORE_ADDR
default_frame_args_address (struct frame_info *next_frame, void **this_cache)
{
  return default_frame_base_address (next_frame, this_cache);
}

const struct frame_base default_frame_base = {
  NULL, /* No parent.  */
  default_frame_base_address,
  default_frame_locals_address,
  default_frame_args_address
};

static struct gdbarch_data *frame_base_data;

struct frame_base_table_entry
{
  frame_base_sniffer_ftype *sniffer;
  struct frame_base_table_entry *next;
};

struct frame_base_table
{
  struct frame_base_table_entry *head;
  struct frame_base_table_entry **tail;
  const struct frame_base *default_base;
};

static void *
frame_base_init (struct obstack *obstack)
{
  struct frame_base_table *table
    = OBSTACK_ZALLOC (obstack, struct frame_base_table);
  table->tail = &table->head;
  table->default_base = &default_frame_base;
  return table;
}

void
frame_base_append_sniffer (struct gdbarch *gdbarch,
			   frame_base_sniffer_ftype *sniffer)
{
  struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
  (*table->tail) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_base_table_entry);
  (*table->tail)->sniffer = sniffer;
  table->tail = &(*table->tail)->next;
}

void
frame_base_set_default (struct gdbarch *gdbarch,
			const struct frame_base *default_base)
{
  struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
  table->default_base = default_base;
}

const struct frame_base *
frame_base_find_by_frame (struct frame_info *next_frame)
{
  struct gdbarch *gdbarch = get_frame_arch (next_frame);
  struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
  struct frame_base_table_entry *entry;

  for (entry = table->head; entry != NULL; entry = entry->next)
    {
      const struct frame_base *desc = NULL;
      desc = entry->sniffer (next_frame);
      if (desc != NULL)
	return desc;
    }
  return table->default_base;
}

extern initialize_file_ftype _initialize_frame_base; /* -Wmissing-prototypes */

void
_initialize_frame_base (void)
{
  frame_base_data = gdbarch_data_register_pre_init (frame_base_init);
}