gnu/dist/gdb6/gdb/frame-base.c

   1 /* Definitions for frame address handler, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2003, 2004 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., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #include "defs.h"
  23 #include "frame-base.h"
  24 #include "frame.h"
  25 #include "gdb_obstack.h"
  26
  27 /* A default frame base implementations.  If it wasn't for the old
  28    DEPRECATED_FRAME_LOCALS_ADDRESS and DEPRECATED_FRAME_ARGS_ADDRESS,
  29    these could be combined into a single function.  All architectures
  30    really need to override this.  */
  31
  32 static CORE_ADDR
  33 default_frame_base_address (struct frame_info *next_frame, void **this_cache)
  34 {
  35   struct frame_info *this_frame = get_prev_frame (next_frame);
  36   return get_frame_base (this_frame); /* sigh! */
  37 }
  38
  39 static CORE_ADDR
  40 default_frame_locals_address (struct frame_info *next_frame, void **this_cache)
  41 {
  42   return default_frame_base_address (next_frame, this_cache);
  43 }
  44
  45 static CORE_ADDR
  46 default_frame_args_address (struct frame_info *next_frame, void **this_cache)
  47 {
  48   return default_frame_base_address (next_frame, this_cache);
  49 }
  50
  51 const struct frame_base default_frame_base = {
  52   NULL, /* No parent.  */
  53   default_frame_base_address,
  54   default_frame_locals_address,
  55   default_frame_args_address
  56 };
  57
  58 static struct gdbarch_data *frame_base_data;
  59
  60 struct frame_base_table_entry
  61 {
  62   frame_base_sniffer_ftype *sniffer;
  63   struct frame_base_table_entry *next;
  64 };
  65
  66 struct frame_base_table
  67 {
  68   struct frame_base_table_entry *head;
  69   struct frame_base_table_entry **tail;
  70   const struct frame_base *default_base;
  71 };
  72
  73 static void *
  74 frame_base_init (struct obstack *obstack)
  75 {
  76   struct frame_base_table *table
  77     = OBSTACK_ZALLOC (obstack, struct frame_base_table);
  78   table->tail = &table->head;
  79   table->default_base = &default_frame_base;
  80   return table;
  81 }
  82
  83 void
  84 frame_base_append_sniffer (struct gdbarch *gdbarch,
  85                            frame_base_sniffer_ftype *sniffer)
  86 {
  87   struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
  88   (*table->tail) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_base_table_entry);
  89   (*table->tail)->sniffer = sniffer;
  90   table->tail = &(*table->tail)->next;
  91 }
  92
  93 void
  94 frame_base_set_default (struct gdbarch *gdbarch,
  95                         const struct frame_base *default_base)
  96 {
  97   struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
  98   table->default_base = default_base;
  99 }
 100
 101 const struct frame_base *
 102 frame_base_find_by_frame (struct frame_info *next_frame)
 103 {
 104   struct gdbarch *gdbarch = get_frame_arch (next_frame);
 105   struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
 106   struct frame_base_table_entry *entry;
 107
 108   for (entry = table->head; entry != NULL; entry = entry->next)
 109     {
 110       const struct frame_base *desc = NULL;
 111       desc = entry->sniffer (next_frame);
 112       if (desc != NULL)
 113         return desc;
 114     }
 115   return table->default_base;
 116 }
 117
 118 extern initialize_file_ftype _initialize_frame_base; /* -Wmissing-prototypes */
 119
 120 void
 121 _initialize_frame_base (void)
 122 {
 123   frame_base_data = gdbarch_data_register_pre_init (frame_base_init);
 124 }