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