gdb/gdbserver/regcache.c

   1 /* Register support routines for the remote server for GDB.
   2    Copyright (C) 2001, 2002, 2004, 2005, 2007, 2008, 2009
   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 void *
  90 new_register_cache (void)
  91 {
  92   struct inferior_regcache_data *regcache;
  93
  94   if (register_bytes == 0)
  95     return NULL; /* The architecture hasn't been initialized yet.  */
  96
  97   regcache = xmalloc (sizeof (*regcache));
  98
  99   /* Make sure to zero-initialize the register cache when it is created,
 100      in case there are registers the target never fetches.  This way they'll
 101      read as zero instead of garbage.  */
 102   regcache->registers = xcalloc (1, register_bytes);
 103
 104   regcache->registers_valid = 0;
 105
 106   return regcache;
 107 }
 108
 109 void
 110 free_register_cache (void *regcache_p)
 111 {
 112   struct inferior_regcache_data *regcache
 113     = (struct inferior_regcache_data *) regcache_p;
 114
 115   if (regcache)
 116     {
 117       free (regcache->registers);
 118       free (regcache);
 119     }
 120 }
 121
 122 static void
 123 realloc_register_cache (struct inferior_list_entry *thread_p)
 124 {
 125   struct thread_info *thread = (struct thread_info *) thread_p;
 126
 127   free_register_cache (inferior_regcache_data (thread));
 128   set_inferior_regcache_data (thread, new_register_cache ());
 129 }
 130
 131 void
 132 set_register_cache (struct reg *regs, int n)
 133 {
 134   int offset, i;
 135
 136   reg_defs = regs;
 137   num_registers = n;
 138
 139   offset = 0;
 140   for (i = 0; i < n; i++)
 141     {
 142       regs[i].offset = offset;
 143       offset += regs[i].size;
 144     }
 145
 146   register_bytes = offset / 8;
 147
 148   /* Make sure PBUFSIZ is large enough to hold a full register packet.  */
 149   if (2 * register_bytes + 32 > PBUFSIZ)
 150     fatal ("Register packet size exceeds PBUFSIZ.");
 151
 152   /* Re-allocate all pre-existing register caches.  */
 153   for_each_inferior (&all_threads, realloc_register_cache);
 154 }
 155
 156 void
 157 registers_to_string (char *buf)
 158 {
 159   unsigned char *registers = get_regcache (current_inferior, 1)->registers;
 160
 161   convert_int_to_ascii (registers, buf, register_bytes);
 162 }
 163
 164 void
 165 registers_from_string (char *buf)
 166 {
 167   int len = strlen (buf);
 168   unsigned char *registers = get_regcache (current_inferior, 1)->registers;
 169
 170   if (len != register_bytes * 2)
 171     {
 172       warning ("Wrong sized register packet (expected %d bytes, got %d)", 2*register_bytes, len);
 173       if (len > register_bytes * 2)
 174         len = register_bytes * 2;
 175     }
 176   convert_ascii_to_int (buf, registers, len / 2);
 177 }
 178
 179 struct reg *
 180 find_register_by_name (const char *name)
 181 {
 182   int i;
 183
 184   for (i = 0; i < num_registers; i++)
 185     if (!strcmp (name, reg_defs[i].name))
 186       return &reg_defs[i];
 187   fatal ("Unknown register %s requested", name);
 188   return 0;
 189 }
 190
 191 int
 192 find_regno (const char *name)
 193 {
 194   int i;
 195
 196   for (i = 0; i < num_registers; i++)
 197     if (!strcmp (name, reg_defs[i].name))
 198       return i;
 199   fatal ("Unknown register %s requested", name);
 200   return -1;
 201 }
 202
 203 struct reg *
 204 find_register_by_number (int n)
 205 {
 206   return &reg_defs[n];
 207 }
 208
 209 int
 210 register_size (int n)
 211 {
 212   return reg_defs[n].size / 8;
 213 }
 214
 215 static unsigned char *
 216 register_data (int n, int fetch)
 217 {
 218   unsigned char *registers
 219     = get_regcache (current_inferior, fetch)->registers;
 220
 221   return registers + (reg_defs[n].offset / 8);
 222 }
 223
 224 void
 225 supply_register (int n, const void *buf)
 226 {
 227   memcpy (register_data (n, 0), buf, register_size (n));
 228 }
 229
 230 void
 231 supply_register_by_name (const char *name, const void *buf)
 232 {
 233   supply_register (find_regno (name), buf);
 234 }
 235
 236 void
 237 collect_register (int n, void *buf)
 238 {
 239   memcpy (buf, register_data (n, 1), register_size (n));
 240 }
 241
 242 void
 243 collect_register_as_string (int n, char *buf)
 244 {
 245   convert_int_to_ascii (register_data (n, 1), buf, register_size (n));
 246 }
 247
 248 void
 249 collect_register_by_name (const char *name, void *buf)
 250 {
 251   collect_register (find_regno (name), buf);
 252 }