gdb/frame-base.c

   1 /* Definitions for frame address handler, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2003-2018 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
  25 /* A default frame base implementations.  If it wasn't for the old
  26    DEPRECATED_FRAME_LOCALS_ADDRESS and DEPRECATED_FRAME_ARGS_ADDRESS,
  27    these could be combined into a single function.  All architectures
  28    really need to override this.  */
  29
  30 static CORE_ADDR
  31 default_frame_base_address (struct frame_info *this_frame, void **this_cache)
  32 {
  33   return get_frame_base (this_frame); /* sigh! */
  34 }
  35
  36 static CORE_ADDR
  37 default_frame_locals_address (struct frame_info *this_frame, void **this_cache)
  38 {
  39   return default_frame_base_address (this_frame, this_cache);
  40 }
  41
  42 static CORE_ADDR
  43 default_frame_args_address (struct frame_info *this_frame, void **this_cache)
  44 {
  45   return default_frame_base_address (this_frame, this_cache);
  46 }
  47
  48 const struct frame_base default_frame_base = {
  49   NULL, /* No parent.  */
  50   default_frame_base_address,
  51   default_frame_locals_address,
  52   default_frame_args_address
  53 };
  54
  55 static struct gdbarch_data *frame_base_data;
  56
  57 struct frame_base_table_entry
  58 {
  59   frame_base_sniffer_ftype *sniffer;
  60   struct frame_base_table_entry *next;
  61 };
  62
  63 struct frame_base_table
  64 {
  65   struct frame_base_table_entry *head;
  66   struct frame_base_table_entry **tail;
  67   const struct frame_base *default_base;
  68 };
  69
  70 static void *
  71 frame_base_init (struct obstack *obstack)
  72 {
  73   struct frame_base_table *table
  74     = OBSTACK_ZALLOC (obstack, struct frame_base_table);
  75
  76   table->tail = &table->head;
  77   table->default_base = &default_frame_base;
  78   return table;
  79 }
  80
  81 void
  82 frame_base_append_sniffer (struct gdbarch *gdbarch,
  83                            frame_base_sniffer_ftype *sniffer)
  84 {
  85   struct frame_base_table *table
  86     = (struct frame_base_table *) gdbarch_data (gdbarch, frame_base_data);
  87
  88   (*table->tail)
  89     = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_base_table_entry);
  90   (*table->tail)->sniffer = sniffer;
  91   table->tail = &(*table->tail)->next;
  92 }
  93
  94 void
  95 frame_base_set_default (struct gdbarch *gdbarch,
  96                         const struct frame_base *default_base)
  97 {
  98   struct frame_base_table *table
  99     = (struct frame_base_table *) gdbarch_data (gdbarch, frame_base_data);
 100
 101   table->default_base = default_base;
 102 }
 103
 104 const struct frame_base *
 105 frame_base_find_by_frame (struct frame_info *this_frame)
 106 {
 107   struct gdbarch *gdbarch = get_frame_arch (this_frame);
 108   struct frame_base_table *table
 109     = (struct frame_base_table *) gdbarch_data (gdbarch, frame_base_data);
 110   struct frame_base_table_entry *entry;
 111
 112   for (entry = table->head; entry != NULL; entry = entry->next)
 113     {
 114       const struct frame_base *desc = NULL;
 115
 116       desc = entry->sniffer (this_frame);
 117       if (desc != NULL)
 118         return desc;
 119     }
 120   return table->default_base;
 121 }
 122
 123 void
 124 _initialize_frame_base (void)
 125 {
 126   frame_base_data = gdbarch_data_register_pre_init (frame_base_init);
 127 }