gdb/frame-unwind.c

   1 /* Definitions for frame unwinder, 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.h"
  24 #include "frame-unwind.h"
  25 #include "gdb_assert.h"
  26 #include "dummy-frame.h"
  27 #include "gdb_obstack.h"
  28
  29 static struct gdbarch_data *frame_unwind_data;
  30
  31 struct frame_unwind_table_entry
  32 {
  33   frame_unwind_sniffer_ftype *sniffer;
  34   struct frame_unwind_table_entry *next;
  35 };
  36
  37 struct frame_unwind_table
  38 {
  39   struct frame_unwind_table_entry *head;
  40   struct frame_unwind_table_entry **tail;
  41 };
  42
  43 static void *
  44 frame_unwind_init (struct obstack *obstack)
  45 {
  46   struct frame_unwind_table *table
  47     = OBSTACK_ZALLOC (obstack, struct frame_unwind_table);
  48   table->head = OBSTACK_ZALLOC (obstack, struct frame_unwind_table_entry);
  49   table->head->sniffer = dummy_frame_sniffer;
  50   table->tail = &table->head->next;
  51   return table;
  52 }
  53
  54 void
  55 frame_unwind_append_sniffer (struct gdbarch *gdbarch,
  56                              frame_unwind_sniffer_ftype *sniffer)
  57 {
  58   struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
  59   (*table->tail) = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct frame_unwind_table_entry);
  60   (*table->tail)->sniffer = sniffer;
  61   table->tail = &((*table->tail)->next);
  62 }
  63
  64 const struct frame_unwind *
  65 frame_unwind_find_by_frame (struct frame_info *next_frame)
  66 {
  67   int i;
  68   struct gdbarch *gdbarch = get_frame_arch (next_frame);
  69   struct frame_unwind_table *table = gdbarch_data (gdbarch, frame_unwind_data);
  70   struct frame_unwind_table_entry *entry;
  71   if (!DEPRECATED_USE_GENERIC_DUMMY_FRAMES && legacy_frame_p (gdbarch))
  72     /* Seriously old code.  Don't even try to use this new mechanism.
  73        (Note: The variable USE_GENERIC_DUMMY_FRAMES is deprecated, not
  74        the dummy frame mechanism.  All architectures should be using
  75        generic dummy frames).  */
  76     return legacy_saved_regs_unwind;
  77   for (entry = table->head; entry != NULL; entry = entry->next)
  78     {
  79       const struct frame_unwind *desc;
  80       desc = entry->sniffer (next_frame);
  81       if (desc != NULL)
  82         return desc;
  83     }
  84   return legacy_saved_regs_unwind;
  85 }
  86
  87 extern initialize_file_ftype _initialize_frame_unwind; /* -Wmissing-prototypes */
  88
  89 void
  90 _initialize_frame_unwind (void)
  91 {
  92   frame_unwind_data = gdbarch_data_register_pre_init (frame_unwind_init);
  93 }