gdb/gdbserver/server.c

   1 /* Main code for remote server for GDB.
   2    Copyright 1989, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2002
   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 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 "server.h"
  23
  24 int cont_thread;
  25 int general_thread;
  26 int thread_from_wait;
  27 int old_thread_from_wait;
  28 int extended_protocol;
  29 jmp_buf toplevel;
  30
  31 static unsigned char
  32 start_inferior (char *argv[], char *statusptr)
  33 {
  34   /* FIXME Check error? Or turn to void.  */
  35   create_inferior (argv[0], argv);
  36   /* FIXME Print pid properly.  */
  37   fprintf (stderr, "Process %s created; pid = %d\n", argv[0], signal_pid);
  38
  39   /* Wait till we are at 1st instruction in program, return signal number.  */
  40   return mywait (statusptr);
  41 }
  42
  43 static int
  44 attach_inferior (int pid, char *statusptr, unsigned char *sigptr)
  45 {
  46   /* myattach should return -1 if attaching is unsupported,
  47      0 if it succeeded, and call error() otherwise.  */
  48   if (myattach (pid) != 0)
  49     return -1;
  50
  51   add_inferior (pid);
  52
  53   *sigptr = mywait (statusptr);
  54
  55   return 0;
  56 }
  57
  58 extern int remote_debug;
  59
  60 /* Handle all of the extended 'q' packets.  */
  61 void
  62 handle_query (char *own_buf)
  63 {
  64   if (strcmp ("qSymbol::", own_buf) == 0)
  65     {
  66 #if 0
  67       strcpy (own_buf, "qSymbol:");
  68       hexify (own_buf + strlen ("qSymbol:"), "main", 4);
  69       putpkt (own_buf);
  70       getpkt (own_buf);
  71       fprintf (stderr, "Got %s", own_buf);
  72 #endif
  73       strcpy (own_buf, "OK");
  74       return;
  75     }
  76
  77   /* Otherwise we didn't know what packet it was.  Say we didn't
  78      understand it.  */
  79   own_buf[0] = 0;
  80 }
  81
  82 static int attached;
  83
  84 int
  85 main (int argc, char *argv[])
  86 {
  87   char ch, status, *own_buf, mem_buf[2000];
  88   int i = 0;
  89   unsigned char signal;
  90   unsigned int len;
  91   CORE_ADDR mem_addr;
  92   int bad_attach;
  93   int pid;
  94   char *arg_end;
  95
  96   if (setjmp (toplevel))
  97     {
  98       fprintf (stderr, "Exiting\n");
  99       exit (1);
 100     }
 101
 102   bad_attach = 0;
 103   pid = 0;
 104   attached = 0;
 105   if (argc >= 3 && strcmp (argv[2], "--attach") == 0)
 106     {
 107       if (argc == 4
 108           && argv[3] != '\0'
 109           && (pid = strtoul (argv[3], &arg_end, 10)) != 0
 110           && *arg_end == '\0')
 111         {
 112           ;
 113         }
 114       else
 115         bad_attach = 1;
 116     }
 117
 118   if (argc < 3 || bad_attach)
 119     error ("Usage:\tgdbserver tty prog [args ...]\n"
 120                  "\tgdbserver tty --attach pid");
 121
 122   initialize_low ();
 123
 124   own_buf = malloc (PBUFSIZ);
 125
 126   if (pid == 0)
 127     {
 128       /* Wait till we are at first instruction in program.  */
 129       signal = start_inferior (&argv[2], &status);
 130
 131       /* We are now stopped at the first instruction of the target process */
 132     }
 133   else
 134     {
 135       switch (attach_inferior (pid, &status, &signal))
 136         {
 137         case -1:
 138           error ("Attaching not supported on this target");
 139           break;
 140         default:
 141           attached = 1;
 142           break;
 143         }
 144     }
 145
 146   while (1)
 147     {
 148       remote_open (argv[1]);
 149
 150     restart:
 151       setjmp (toplevel);
 152       while (getpkt (own_buf) > 0)
 153         {
 154           unsigned char sig;
 155           i = 0;
 156           ch = own_buf[i++];
 157           switch (ch)
 158             {
 159             case 'q':
 160               handle_query (own_buf);
 161               break;
 162             case 'd':
 163               remote_debug = !remote_debug;
 164               break;
 165             case '!':
 166               if (attached == 0)
 167                 {
 168                   extended_protocol = 1;
 169                   prepare_resume_reply (own_buf, status, signal);
 170                 }
 171               else
 172                 {
 173                   /* We can not use the extended protocol if we are
 174                      attached, because we can not restart the running
 175                      program.  So return unrecognized.  */
 176                   own_buf[0] = '\0';
 177                 }
 178               break;
 179             case '?':
 180               prepare_resume_reply (own_buf, status, signal);
 181               break;
 182             case 'H':
 183               switch (own_buf[1])
 184                 {
 185                 case 'g':
 186                   general_thread = strtol (&own_buf[2], NULL, 16);
 187                   write_ok (own_buf);
 188                   fetch_inferior_registers (0);
 189                   break;
 190                 case 'c':
 191                   cont_thread = strtol (&own_buf[2], NULL, 16);
 192                   write_ok (own_buf);
 193                   break;
 194                 default:
 195                   /* Silently ignore it so that gdb can extend the protocol
 196                      without compatibility headaches.  */
 197                   own_buf[0] = '\0';
 198                   break;
 199                 }
 200               break;
 201             case 'g':
 202               registers_to_string (own_buf);
 203               break;
 204             case 'G':
 205               registers_from_string (&own_buf[1]);
 206               store_inferior_registers (-1);
 207               write_ok (own_buf);
 208               break;
 209             case 'm':
 210               decode_m_packet (&own_buf[1], &mem_addr, &len);
 211               read_inferior_memory (mem_addr, mem_buf, len);
 212               convert_int_to_ascii (mem_buf, own_buf, len);
 213               break;
 214             case 'M':
 215               decode_M_packet (&own_buf[1], &mem_addr, &len, mem_buf);
 216               if (write_inferior_memory (mem_addr, mem_buf, len) == 0)
 217                 write_ok (own_buf);
 218               else
 219                 write_enn (own_buf);
 220               break;
 221             case 'C':
 222               convert_ascii_to_int (own_buf + 1, &sig, 1);
 223               if (target_signal_to_host_p (sig))
 224                 signal = target_signal_to_host (sig);
 225               else
 226                 signal = 0;
 227               myresume (0, signal);
 228               signal = mywait (&status);
 229               prepare_resume_reply (own_buf, status, signal);
 230               break;
 231             case 'S':
 232               convert_ascii_to_int (own_buf + 1, &sig, 1);
 233               if (target_signal_to_host_p (sig))
 234                 signal = target_signal_to_host (sig);
 235               else
 236                 signal = 0;
 237               myresume (1, signal);
 238               signal = mywait (&status);
 239               prepare_resume_reply (own_buf, status, signal);
 240               break;
 241             case 'c':
 242               myresume (0, 0);
 243               signal = mywait (&status);
 244               prepare_resume_reply (own_buf, status, signal);
 245               break;
 246             case 's':
 247               myresume (1, 0);
 248               signal = mywait (&status);
 249               prepare_resume_reply (own_buf, status, signal);
 250               break;
 251             case 'k':
 252               fprintf (stderr, "Killing inferior\n");
 253               kill_inferior ();
 254               /* When using the extended protocol, we start up a new
 255                  debugging session.   The traditional protocol will
 256                  exit instead.  */
 257               if (extended_protocol)
 258                 {
 259                   write_ok (own_buf);
 260                   fprintf (stderr, "GDBserver restarting\n");
 261
 262                   /* Wait till we are at 1st instruction in prog.  */
 263                   signal = start_inferior (&argv[2], &status);
 264                   goto restart;
 265                   break;
 266                 }
 267               else
 268                 {
 269                   exit (0);
 270                   break;
 271                 }
 272             case 'T':
 273               if (mythread_alive (strtol (&own_buf[1], NULL, 16)))
 274                 write_ok (own_buf);
 275               else
 276                 write_enn (own_buf);
 277               break;
 278             case 'R':
 279               /* Restarting the inferior is only supported in the
 280                  extended protocol.  */
 281               if (extended_protocol)
 282                 {
 283                   kill_inferior ();
 284                   write_ok (own_buf);
 285                   fprintf (stderr, "GDBserver restarting\n");
 286
 287                   /* Wait till we are at 1st instruction in prog.  */
 288                   signal = start_inferior (&argv[2], &status);
 289                   goto restart;
 290                   break;
 291                 }
 292               else
 293                 {
 294                   /* It is a request we don't understand.  Respond with an
 295                      empty packet so that gdb knows that we don't support this
 296                      request.  */
 297                   own_buf[0] = '\0';
 298                   break;
 299                 }
 300             default:
 301               /* It is a request we don't understand.  Respond with an
 302                  empty packet so that gdb knows that we don't support this
 303                  request.  */
 304               own_buf[0] = '\0';
 305               break;
 306             }
 307
 308           putpkt (own_buf);
 309
 310           if (status == 'W')
 311             fprintf (stderr,
 312                      "\nChild exited with status %d\n", sig);
 313           if (status == 'X')
 314             fprintf (stderr, "\nChild terminated with signal = 0x%x\n", sig);
 315           if (status == 'W' || status == 'X')
 316             {
 317               if (extended_protocol)
 318                 {
 319                   fprintf (stderr, "Killing inferior\n");
 320                   kill_inferior ();
 321                   write_ok (own_buf);
 322                   fprintf (stderr, "GDBserver restarting\n");
 323
 324                   /* Wait till we are at 1st instruction in prog.  */
 325                   signal = start_inferior (&argv[2], &status);
 326                   goto restart;
 327                   break;
 328                 }
 329               else
 330                 {
 331                   fprintf (stderr, "GDBserver exiting\n");
 332                   exit (0);
 333                 }
 334             }
 335         }
 336
 337       /* We come here when getpkt fails.
 338
 339          For the extended remote protocol we exit (and this is the only
 340          way we gracefully exit!).
 341
 342          For the traditional remote protocol close the connection,
 343          and re-open it at the top of the loop.  */
 344       if (extended_protocol)
 345         {
 346           remote_close ();
 347           exit (0);
 348         }
 349       else
 350         {
 351           fprintf (stderr, "Remote side has terminated connection.  "
 352                            "GDBserver will reopen the connection.\n");
 353           remote_close ();
 354         }
 355     }
 356 }