gdb/gdbserver/regcache.c

   1 /* Register support routines for the remote server for GDB.
   2    Copyright (C) 2001, 2002, 2004, 2005, 2007, 2008
   3    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 "server.h"
  21 #include "regdef.h"
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 /* The private data for the register cache.  Note that we have one
  27    per inferior; this is primarily for simplicity, as the performance
  28    benefit is minimal.  */
  29
  30 struct inferior_regcache_data
  31 {
  32   int registers_valid;
  33   unsigned char *registers;
  34 };
  35
  36 static int register_bytes;
  37
  38 static struct reg *reg_defs;
  39 static int num_registers;
  40
  41 const char **gdbserver_expedite_regs;
  42
  43 static struct inferior_regcache_data *
  44 get_regcache (struct thread_info *inf, int fetch)
  45 {
  46   struct inferior_regcache_data *regcache;
  47
  48   regcache = (struct inferior_regcache_data *) inferior_regcache_data (inf);
  49
  50   if (regcache == NULL)
  51     fatal ("no register cache");
  52
  53   /* FIXME - fetch registers for INF */
  54   if (fetch && regcache->registers_valid == 0)
  55     {
  56       fetch_inferior_registers (0);
  57       regcache->registers_valid = 1;
  58     }
  59
  60   return regcache;
  61 }
  62
  63 void
  64 regcache_invalidate_one (struct inferior_list_entry *entry)
  65 {
  66   struct thread_info *thread = (struct thread_info *) entry;
  67   struct inferior_regcache_data *regcache;
  68
  69   regcache = (struct inferior_regcache_data *) inferior_regcache_data (thread);
  70
  71   if (regcache->registers_valid)
  72     {
  73       struct thread_info *saved_inferior = current_inferior;
  74
  75       current_inferior = thread;
  76       store_inferior_registers (-1);
  77       current_inferior = saved_inferior;
  78     }
  79
  80   regcache->registers_valid = 0;
  81 }
  82
  83 void
  84 regcache_invalidate ()
  85 {
  86   for_each_inferior (&all_threads, regcache_invalidate_one);
  87 }
  88
  89 int
  90 registers_length (void)
  91 {
  92   return 2 * register_bytes;
  93 }
  94
  95 void *
  96 new_register_cache (void)
  97 {
  98   struct inferior_regcache_data *regcache;
  99
 100   regcache = malloc (sizeof (*regcache));
 101
 102   /* Make sure to zero-initialize the register cache when it is created,
 103      in case there are registers the target never fetches.  This way they'll
 104      read as zero instead of garbage.  */
 105   regcache->registers = calloc (1, register_bytes);
 106   if (regcache->registers == NULL)
 107     fatal ("Could not allocate register cache.");
 108
 109   regcache->registers_valid = 0;
 110
 111   return regcache;
 112 }
 113
 114 void
 115 free_register_cache (void *regcache_p)
 116 {
 117   struct inferior_regcache_data *regcache
 118     = (struct inferior_regcache_data *) regcache_p;
 119
 120   free (regcache->registers);
 121   free (regcache);
 122 }
 123
 124 static void
 125 realloc_register_cache (struct inferior_list_entry *thread_p)
 126 {
 127   struct thread_info *thread = (struct thread_info *) thread_p;
 128
 129   free_register_cache (inferior_regcache_data (thread));
 130   set_inferior_regcache_data (thread, new_register_cache ());
 131 }
 132
 133 void
 134 set_register_cache (struct reg *regs, int n)
 135 {
 136   int offset, i;
 137
 138   reg_defs = regs;
 139   num_registers = n;
 140
 141   offset = 0;
 142   for (i = 0; i < n; i++)
 143     {
 144       regs[i].offset = offset;
 145       offset += regs[i].size;
 146     }
 147
 148   register_bytes = offset / 8;
 149
 150   /* Re-allocate all pre-existing register caches.  */
 151   for_each_inferior (&all_threads, realloc_register_cache);
 152 }
 153
 154 void
 155 registers_to_string (char *buf)
 156 {
 157   unsigned char *registers = get_regcache (current_inferior, 1)->registers;
 158
 159   convert_int_to_ascii (registers, buf, register_bytes);
 160 }
 161
 162 void
 163 registers_from_string (char *buf)
 164 {
 165   int len = strlen (buf);
 166   unsigned char *registers = get_regcache (current_inferior, 1)->registers;
 167
 168   if (len != register_bytes * 2)
 169     {
 170       warning ("Wrong sized register packet (expected %d bytes, got %d)", 2*register_bytes, len);
 171       if (len > register_bytes * 2)
 172         len = register_bytes * 2;
 173     }
 174   convert_ascii_to_int (buf, registers, len / 2);
 175 }
 176
 177 struct reg *
 178 find_register_by_name (const char *name)
 179 {
 180   int i;
 181
 182   for (i = 0; i < num_registers; i++)
 183     if (!strcmp (name, reg_defs[i].name))
 184       return &reg_defs[i];
 185   fatal ("Unknown register %s requested", name);
 186   return 0;
 187 }
 188
 189 int
 190 find_regno (const char *name)
 191 {
 192   int i;
 193
 194   for (i = 0; i < num_registers; i++)
 195     if (!strcmp (name, reg_defs[i].name))
 196       return i;
 197   fatal ("Unknown register %s requested", name);
 198   return -1;
 199 }
 200
 201 struct reg *
 202 find_register_by_number (int n)
 203 {
 204   return &reg_defs[n];
 205 }
 206
 207 int
 208 register_size (int n)
 209 {
 210   return reg_defs[n].size / 8;
 211 }
 212
 213 static unsigned char *
 214 register_data (int n, int fetch)
 215 {
 216   unsigned char *registers
 217     = get_regcache (current_inferior, fetch)->registers;
 218
 219   return registers + (reg_defs[n].offset / 8);
 220 }
 221
 222 void
 223 supply_register (int n, const void *buf)
 224 {
 225   memcpy (register_data (n, 0), buf, register_size (n));
 226 }
 227
 228 void
 229 supply_register_by_name (const char *name, const void *buf)
 230 {
 231   supply_register (find_regno (name), buf);
 232 }
 233
 234 void
 235 collect_register (int n, void *buf)
 236 {
 237   memcpy (buf, register_data (n, 1), register_size (n));
 238 }
 239
 240 void
 241 collect_register_as_string (int n, char *buf)
 242 {
 243   convert_int_to_ascii (register_data (n, 1), buf, register_size (n));
 244 }
 245
 246 void
 247 collect_register_by_name (const char *name, void *buf)
 248 {
 249   collect_register (find_regno (name), buf);
 250 }