gdb/frame-base.c

   1 /* Definitions for frame address handler, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2003-2020 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 3 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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "frame-base.h"
  22 #include "frame.h"
  23 #include "gdb_obstack.h"
  24 #include "gdbarch.h"
  25
  26 /* A default frame base implementations.  If it wasn't for the old
  27    DEPRECATED_FRAME_LOCALS_ADDRESS and DEPRECATED_FRAME_ARGS_ADDRESS,
  28    these could be combined into a single function.  All architectures
  29    really need to override this.  */
  30
  31 static CORE_ADDR
  32 default_frame_base_address (struct frame_info *this_frame, void **this_cache)
  33 {
  34   return get_frame_base (this_frame); /* sigh! */
  35 }
  36
  37 static CORE_ADDR
  38 default_frame_locals_address (struct frame_info *this_frame, void **this_cache)
  39 {
  40   return default_frame_base_address (this_frame, this_cache);
  41 }
  42
  43 static CORE_ADDR
  44 default_frame_args_address (struct frame_info *this_frame, void **this_cache)
  45 {
  46   return default_frame_base_address (this_frame, this_cache);
  47 }
  48
  49 const struct frame_base default_frame_base = {
  50   NULL, /* No parent.  */
  51   default_frame_base_address,
  52   default_frame_locals_address,
  53   default_frame_args_address
  54 };
  55
  56 static struct gdbarch_data *frame_base_data;
  57
  58 struct frame_base_table_entry
  59 {
  60   frame_base_sniffer_ftype *sniffer;
  61   struct frame_base_table_entry *next;
  62 };
  63
  64 struct frame_base_table
  65 {
  66   struct frame_base_table_entry *head;
  67   struct frame_base_table_entry **tail;
  68   const struct frame_base *default_base;
  69 };
  70
  71 static void *
  72 frame_base_init (struct obstack *obstack)
  73 {
  74   struct frame_base_table *table
  75     = OBSTACK_ZALLOC (obstack, struct frame_base_table);
  76
  77   table->tail = &table->head;
  78   table->default_base = &default_frame_base;
  79   return table;
  80 }
  81
  82 void
  83 frame_base_append_sniffer (struct gdbarch *gdbarch,
  84                            frame_base_sniffer_ftype *sniffer)
  85 {
  86   struct frame_base_table *table
  87     = (struct frame_base_table *) gdbarch_data (gdbarch, frame_base_data);
  88
  89   (*table->tail)
  90     = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_base_table_entry);
  91   (*table->tail)->sniffer = sniffer;
  92   table->tail = &(*table->tail)->next;
  93 }
  94
  95 void
  96 frame_base_set_default (struct gdbarch *gdbarch,
  97                         const struct frame_base *default_base)
  98 {
  99   struct frame_base_table *table
 100     = (struct frame_base_table *) gdbarch_data (gdbarch, frame_base_data);
 101
 102   table->default_base = default_base;
 103 }
 104
 105 const struct frame_base *
 106 frame_base_find_by_frame (struct frame_info *this_frame)
 107 {
 108   struct gdbarch *gdbarch = get_frame_arch (this_frame);
 109   struct frame_base_table *table
 110     = (struct frame_base_table *) gdbarch_data (gdbarch, frame_base_data);
 111   struct frame_base_table_entry *entry;
 112
 113   for (entry = table->head; entry != NULL; entry = entry->next)
 114     {
 115       const struct frame_base *desc = NULL;
 116
 117       desc = entry->sniffer (this_frame);
 118       if (desc != NULL)
 119         return desc;
 120     }
 121   return table->default_base;
 122 }
 123
 124 void _initialize_frame_base ();
 125 void
 126 _initialize_frame_base ()
 127 {
 128   frame_base_data = gdbarch_data_register_pre_init (frame_base_init);
 129 }