gdb/frame-base.c

   1 /* Definitions for frame address handler, for GDB, the GNU debugger.
   2
   3    Copyright 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., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, 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   if (DEPRECATED_FRAME_LOCALS_ADDRESS_P ())
  43     {
  44       /* This is bad.  The computation of per-frame locals address
  45          should use a per-frame frame-base.  */
  46       struct frame_info *this_frame = get_prev_frame (next_frame);
  47       return DEPRECATED_FRAME_LOCALS_ADDRESS (this_frame);
  48     }
  49   return default_frame_base_address (next_frame, this_cache);
  50 }
  51
  52 static CORE_ADDR
  53 default_frame_args_address (struct frame_info *next_frame, void **this_cache)
  54 {
  55   if (DEPRECATED_FRAME_ARGS_ADDRESS_P ())
  56     {
  57       struct frame_info *this_frame = get_prev_frame (next_frame);
  58       return DEPRECATED_FRAME_ARGS_ADDRESS (this_frame);
  59     }
  60   return default_frame_base_address (next_frame, this_cache);
  61 }
  62
  63 const struct frame_base default_frame_base = {
  64   NULL, /* No parent.  */
  65   default_frame_base_address,
  66   default_frame_locals_address,
  67   default_frame_args_address
  68 };
  69
  70 static struct gdbarch_data *frame_base_data;
  71
  72 struct frame_base_table_entry
  73 {
  74   frame_base_sniffer_ftype *sniffer;
  75   struct frame_base_table_entry *next;
  76 };
  77
  78 struct frame_base_table
  79 {
  80   struct frame_base_table_entry *head;
  81   struct frame_base_table_entry **tail;
  82   const struct frame_base *default_base;
  83 };
  84
  85 static void *
  86 frame_base_init (struct obstack *obstack)
  87 {
  88   struct frame_base_table *table
  89     = OBSTACK_ZALLOC (obstack, struct frame_base_table);
  90   table->tail = &table->head;
  91   table->default_base = &default_frame_base;
  92   return table;
  93 }
  94
  95 void
  96 frame_base_append_sniffer (struct gdbarch *gdbarch,
  97                            frame_base_sniffer_ftype *sniffer)
  98 {
  99   struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
 100   (*table->tail) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_base_table_entry);
 101   (*table->tail)->sniffer = sniffer;
 102   table->tail = &(*table->tail)->next;
 103 }
 104
 105 void
 106 frame_base_set_default (struct gdbarch *gdbarch,
 107                         const struct frame_base *default_base)
 108 {
 109   struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
 110   table->default_base = default_base;
 111 }
 112
 113 const struct frame_base *
 114 frame_base_find_by_frame (struct frame_info *next_frame)
 115 {
 116   struct gdbarch *gdbarch = get_frame_arch (next_frame);
 117   struct frame_base_table *table = gdbarch_data (gdbarch, frame_base_data);
 118   struct frame_base_table_entry *entry;
 119
 120   for (entry = table->head; entry != NULL; entry = entry->next)
 121     {
 122       const struct frame_base *desc = NULL;
 123       desc = entry->sniffer (next_frame);
 124       if (desc != NULL)
 125         return desc;
 126     }
 127   return table->default_base;
 128 }
 129
 130 extern initialize_file_ftype _initialize_frame_base; /* -Wmissing-prototypes */
 131
 132 void
 133 _initialize_frame_base (void)
 134 {
 135   frame_base_data = gdbarch_data_register_pre_init (frame_base_init);
 136 }