gdb/remote-sim.c

   1 /* Generic remote debugging interface for simulators.
   2    Copyright 1993, 1994, 1996, 1997 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support.
   4    Steve Chamberlain (sac@cygnus.com).
   5
   6 This file is part of GDB.
   7
   8 This program is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2 of the License, or
  11 (at your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #include "defs.h"
  23 #include "inferior.h"
  24 #include "wait.h"
  25 #include "value.h"
  26 #include "gdb_string.h"
  27 #include <ctype.h>
  28 #include <fcntl.h>
  29 #include <signal.h>
  30 #include <setjmp.h>
  31 #include <errno.h>
  32 #include "terminal.h"
  33 #include "target.h"
  34 #include "gdbcore.h"
  35 #include "callback.h"
  36 #include "remote-sim.h"
  37 #include "remote-utils.h"
  38 #include "command.h"
  39
  40 /* Prototypes */
  41
  42 static void dump_mem PARAMS ((char *buf, int len));
  43
  44 static void init_callbacks PARAMS ((void));
  45
  46 static void end_callbacks PARAMS ((void));
  47
  48 static int gdb_os_write_stdout PARAMS ((host_callback *, const char *, int));
  49
  50 static void gdb_os_flush_stdout PARAMS ((host_callback *));
  51
  52 static int gdb_os_write_stderr PARAMS ((host_callback *, const char *, int));
  53
  54 static void gdb_os_flush_stderr PARAMS ((host_callback *));
  55
  56 static int gdb_os_poll_quit PARAMS ((host_callback *));
  57
  58 /* printf_filtered is depreciated */
  59 static void gdb_os_printf_filtered PARAMS ((host_callback *, const char *, ...));
  60
  61 static void gdb_os_vprintf_filtered PARAMS ((host_callback *, const char *, va_list));
  62
  63 static void gdb_os_evprintf_filtered PARAMS ((host_callback *, const char *, va_list));
  64
  65 static void gdb_os_error PARAMS ((host_callback *, const char *, ...));
  66
  67 static void gdbsim_fetch_register PARAMS ((int regno));
  68
  69 static void gdbsim_store_register PARAMS ((int regno));
  70
  71 static void gdbsim_kill PARAMS ((void));
  72
  73 static void gdbsim_load PARAMS ((char *prog, int fromtty));
  74
  75 static void gdbsim_create_inferior PARAMS ((char *exec_file, char *args, char **env));
  76
  77 static void gdbsim_open PARAMS ((char *args, int from_tty));
  78
  79 static void gdbsim_close PARAMS ((int quitting));
  80
  81 static void gdbsim_detach PARAMS ((char *args, int from_tty));
  82
  83 static void gdbsim_resume PARAMS ((int pid, int step, enum target_signal siggnal));
  84
  85 static int gdbsim_wait PARAMS ((int pid, struct target_waitstatus *status));
  86
  87 static void gdbsim_prepare_to_store PARAMS ((void));
  88
  89 static int gdbsim_xfer_inferior_memory PARAMS ((CORE_ADDR memaddr,
  90                                                 char *myaddr, int len,
  91                                                 int write,
  92                                                 struct target_ops *target));
  93
  94 static void gdbsim_files_info PARAMS ((struct target_ops *target));
  95
  96 static void gdbsim_mourn_inferior PARAMS ((void));
  97
  98 static void gdbsim_stop PARAMS ((void));
  99
 100 static void simulator_command PARAMS ((char *args, int from_tty));
 101
 102 /* Naming convention:
 103
 104    sim_* are the interface to the simulator (see remote-sim.h).
 105    gdbsim_* are stuff which is internal to gdb.  */
 106
 107 /* Forward data declarations */
 108 extern struct target_ops gdbsim_ops;
 109
 110 static int program_loaded = 0;
 111
 112 /* We must keep track of whether the simulator has been opened or not because
 113    GDB can call a target's close routine twice, but sim_close doesn't allow
 114    this.  We also need to record the result of sim_open so we can pass it
 115    back to the other sim_foo routines.  */
 116 static SIM_DESC gdbsim_desc = 0;
 117
 118 static void
 119 dump_mem (buf, len)
 120      char *buf;
 121      int len;
 122 {
 123   if (len <= 8)
 124     {
 125       if (len == 8 || len == 4)
 126         {
 127           long l[2];
 128           memcpy (l, buf, len);
 129           printf_filtered ("\t0x%x", l[0]);
 130           printf_filtered (len == 8 ? " 0x%x\n" : "\n", l[1]);
 131         }
 132       else
 133         {
 134           int i;
 135           printf_filtered ("\t");
 136           for (i = 0; i < len; i++)
 137             printf_filtered ("0x%x ", buf[i]);
 138           printf_filtered ("\n");
 139         }
 140     }
 141 }
 142
 143 static host_callback gdb_callback;
 144 static int callbacks_initialized = 0;
 145
 146 /* Initialize gdb_callback.  */
 147
 148 static void
 149 init_callbacks ()
 150 {
 151   if (! callbacks_initialized)
 152     {
 153       gdb_callback = default_callback;
 154       gdb_callback.init (&gdb_callback);
 155       gdb_callback.write_stdout = gdb_os_write_stdout;
 156       gdb_callback.flush_stdout = gdb_os_flush_stdout;
 157       gdb_callback.write_stderr = gdb_os_write_stderr;
 158       gdb_callback.flush_stderr = gdb_os_flush_stderr;
 159       gdb_callback.printf_filtered = gdb_os_printf_filtered;
 160       gdb_callback.vprintf_filtered = gdb_os_vprintf_filtered;
 161       gdb_callback.evprintf_filtered = gdb_os_evprintf_filtered;
 162       gdb_callback.error = gdb_os_error;
 163       gdb_callback.poll_quit = gdb_os_poll_quit;
 164       gdb_callback.magic = HOST_CALLBACK_MAGIC;
 165       callbacks_initialized = 1;
 166     }
 167 }
 168
 169 /* Release callbacks (free resources used by them).  */
 170
 171 static void
 172 end_callbacks ()
 173 {
 174   if (callbacks_initialized)
 175     {
 176       gdb_callback.shutdown (&gdb_callback);
 177       callbacks_initialized = 0;
 178     }
 179 }
 180
 181 /* GDB version of os_write_stdout callback.  */
 182
 183 static int
 184 gdb_os_write_stdout (p, buf, len)
 185      host_callback *p;
 186      const char *buf;
 187      int len;
 188 {
 189   int i;
 190   char b[2];
 191
 192   for (i = 0; i < len; i++)
 193     {
 194       b[0] = buf[i];
 195       b[1] = 0;
 196       if (target_output_hook)
 197         target_output_hook (b);
 198       else
 199         fputs_filtered (b, gdb_stdout);
 200     }
 201   return len;
 202 }
 203
 204 /* GDB version of os_flush_stdout callback.  */
 205
 206 static void
 207 gdb_os_flush_stdout (p)
 208      host_callback *p;
 209 {
 210   gdb_flush (gdb_stdout);
 211 }
 212
 213 /* GDB version of os_write_stderr callback.  */
 214
 215 static int
 216 gdb_os_write_stderr (p, buf, len)
 217      host_callback *p;
 218      const char *buf;
 219      int len;
 220 {
 221   int i;
 222   char b[2];
 223
 224   for (i = 0; i < len; i++)
 225     {
 226       b[0] = buf[i];
 227       b[1] = 0;
 228       if (target_output_hook)
 229         target_output_hook (b);
 230       else
 231         fputs_filtered (b, gdb_stderr);
 232     }
 233   return len;
 234 }
 235
 236 /* GDB version of os_flush_stderr callback.  */
 237
 238 static void
 239 gdb_os_flush_stderr (p)
 240      host_callback *p;
 241 {
 242   gdb_flush (gdb_stderr);
 243 }
 244
 245 /* GDB version of printf_filtered callback.  */
 246
 247 /* VARARGS */
 248 static void
 249 #ifdef ANSI_PROTOTYPES
 250 gdb_os_printf_filtered (host_callback *p, const char *format, ...)
 251 #else
 252 gdb_os_printf_filtered (p, va_alist)
 253      host_callback *p;
 254      va_dcl
 255 #endif
 256 {
 257   va_list args;
 258 #ifdef ANSI_PROTOTYPES
 259   va_start (args, format);
 260 #else
 261   char *format;
 262
 263   va_start (args);
 264   format = va_arg (args, char *);
 265 #endif
 266
 267   vfprintf_filtered (gdb_stdout, format, args);
 268
 269   va_end (args);
 270 }
 271
 272 /* GDB version of error vprintf_filtered.  */
 273
 274 /* VARARGS */
 275 static void
 276 #ifdef ANSI_PROTOTYPES
 277 gdb_os_vprintf_filtered (host_callback *p, const char *format, va_list ap)
 278 #else
 279 gdb_os_vprintf_filtered (p, format, ap)
 280      host_callback *p;
 281      char *format;
 282      va_list ap;
 283 #endif
 284 {
 285   vfprintf_filtered (gdb_stdout, format, ap);
 286 }
 287
 288 /* GDB version of error evprintf_filtered.  */
 289
 290 /* VARARGS */
 291 static void
 292 #ifdef ANSI_PROTOTYPES
 293 gdb_os_evprintf_filtered (host_callback *p, const char *format, va_list ap)
 294 #else
 295 gdb_os_evprintf_filtered (p, format, ap)
 296      host_callback *p;
 297      char *format;
 298      va_list ap;
 299 #endif
 300 {
 301   vfprintf_filtered (gdb_stderr, format, ap);
 302 }
 303
 304 /* GDB version of error callback.  */
 305
 306 /* VARARGS */
 307 static void
 308 #ifdef ANSI_PROTOTYPES
 309 gdb_os_error (host_callback *p, const char *format, ...)
 310 #else
 311 gdb_os_error (p, va_alist)
 312      host_callback *p;
 313      va_dcl
 314 #endif
 315 {
 316   if (error_hook)
 317     (*error_hook) ();
 318   else
 319     {
 320       va_list args;
 321 #ifdef ANSI_PROTOTYPES
 322       va_start (args, format);
 323 #else
 324       char *format;
 325
 326       va_start (args);
 327       format = va_arg (args, char *);
 328 #endif
 329
 330       error_begin ();
 331       vfprintf_filtered (gdb_stderr, format, args);
 332       fprintf_filtered (gdb_stderr, "\n");
 333       va_end (args);
 334       return_to_top_level (RETURN_ERROR);
 335     }
 336 }
 337
 338 static void
 339 gdbsim_fetch_register (regno)
 340 int regno;
 341 {
 342   if (regno == -1)
 343     {
 344       for (regno = 0; regno < NUM_REGS; regno++)
 345         gdbsim_fetch_register (regno);
 346     }
 347   else
 348     {
 349       char buf[MAX_REGISTER_RAW_SIZE];
 350
 351       sim_fetch_register (gdbsim_desc, regno, buf);
 352       supply_register (regno, buf);
 353       if (sr_get_debug ())
 354         {
 355           printf_filtered ("gdbsim_fetch_register: %d", regno);
 356           /* FIXME: We could print something more intelligible.  */
 357           dump_mem (buf, REGISTER_RAW_SIZE (regno));
 358         }
 359     }
 360 }
 361
 362
 363 static void
 364 gdbsim_store_register (regno)
 365 int regno;
 366 {
 367   if (regno  == -1)
 368     {
 369       for (regno = 0; regno < NUM_REGS; regno++)
 370         gdbsim_store_register (regno);
 371     }
 372   else
 373     {
 374       /* FIXME: Until read_register() returns LONGEST, we have this.  */
 375       char tmp[MAX_REGISTER_RAW_SIZE];
 376       read_register_gen (regno, tmp);
 377       sim_store_register (gdbsim_desc, regno, tmp);
 378       if (sr_get_debug ())
 379         {
 380           printf_filtered ("gdbsim_store_register: %d", regno);
 381           /* FIXME: We could print something more intelligible.  */
 382           dump_mem (tmp, REGISTER_RAW_SIZE (regno));
 383         }
 384     }
 385 }
 386
 387 /* Kill the running program.  This may involve closing any open files
 388    and releasing other resources acquired by the simulated program.  */
 389
 390 static void
 391 gdbsim_kill ()
 392 {
 393   if (sr_get_debug ())
 394     printf_filtered ("gdbsim_kill\n");
 395
 396   /* There is no need to `kill' running simulator - the simulator is
 397      not running */
 398   inferior_pid = 0;
 399 }
 400
 401 /* Load an executable file into the target process.  This is expected to
 402    not only bring new code into the target process, but also to update
 403    GDB's symbol tables to match.  */
 404
 405 static void
 406 gdbsim_load (prog, fromtty)
 407      char *prog;
 408      int fromtty;
 409 {
 410   if (sr_get_debug ())
 411     printf_filtered ("gdbsim_load: prog \"%s\"\n", prog);
 412
 413   inferior_pid = 0;
 414
 415   /* FIXME: We will print two messages on error.
 416      Need error to either not print anything if passed NULL or need
 417      another routine that doesn't take any arguments.  */
 418   if (sim_load (gdbsim_desc, prog, NULL, fromtty) == SIM_RC_FAIL)
 419     error ("unable to load program");
 420
 421   program_loaded = 1;
 422 }
 423
 424
 425 /* Start an inferior process and set inferior_pid to its pid.
 426    EXEC_FILE is the file to run.
 427    ARGS is a string containing the arguments to the program.
 428    ENV is the environment vector to pass.  Errors reported with error().
 429    On VxWorks and various standalone systems, we ignore exec_file.  */
 430 /* This is called not only when we first attach, but also when the
 431    user types "run" after having attached.  */
 432
 433 static void
 434 gdbsim_create_inferior (exec_file, args, env)
 435      char *exec_file;
 436      char *args;
 437      char **env;
 438 {
 439   int len;
 440   char *arg_buf,**argv;
 441   CORE_ADDR entry_pt;
 442
 443   if (! program_loaded)
 444     error ("No program loaded.");
 445
 446   if (sr_get_debug ())
 447     printf_filtered ("gdbsim_create_inferior: exec_file \"%s\", args \"%s\"\n",
 448       exec_file, args);
 449
 450   if (exec_file == 0 || exec_bfd == 0)
 451    error ("No exec file specified.");
 452
 453   entry_pt = (CORE_ADDR) bfd_get_start_address (exec_bfd);
 454
 455   gdbsim_kill ();
 456   remove_breakpoints ();
 457   init_wait_for_inferior ();
 458
 459   len = strlen (exec_file) + 1 + strlen (args) + 1 + /*slop*/ 10;
 460   arg_buf = (char *) alloca (len);
 461   arg_buf[0] = '\0';
 462   strcat (arg_buf, exec_file);
 463   strcat (arg_buf, " ");
 464   strcat (arg_buf, args);
 465   argv = buildargv (arg_buf);
 466   make_cleanup (freeargv, (char *) argv);
 467   sim_create_inferior (gdbsim_desc, argv, env);
 468
 469   inferior_pid = 42;
 470   insert_breakpoints ();        /* Needed to get correct instruction in cache */
 471   proceed (entry_pt, TARGET_SIGNAL_DEFAULT, 0);
 472 }
 473
 474 /* The open routine takes the rest of the parameters from the command,
 475    and (if successful) pushes a new target onto the stack.
 476    Targets should supply this routine, if only to provide an error message.  */
 477 /* Called when selecting the simulator. EG: (gdb) target sim name.  */
 478
 479 static void
 480 gdbsim_open (args, from_tty)
 481      char *args;
 482      int from_tty;
 483 {
 484   int len;
 485   char *arg_buf;
 486   char **argv;
 487
 488   if (sr_get_debug ())
 489     printf_filtered ("gdbsim_open: args \"%s\"\n", args ? args : "(null)");
 490
 491   /* Remove current simulator if one exists.  Only do this if the simulator
 492      has been opened because sim_close requires it.
 493      This is important because the call to push_target below will cause
 494      sim_close to be called if the simulator is already open, but push_target
 495      is called after sim_open!  We can't move the call to push_target before
 496      the call to sim_open because sim_open may invoke `error'.  */
 497   if (gdbsim_desc != NULL)
 498     unpush_target (&gdbsim_ops);
 499
 500   len = 7 + 1 + (args ? strlen (args) : 0) + 50;
 501   arg_buf = (char *) alloca (len);
 502   sprintf (arg_buf, "gdbsim%s%s",
 503            args ? " " : "", args ? args : "");
 504 #ifdef TARGET_BYTE_ORDER_SELECTABLE
 505   /* Since GDB always closes the target and updates byte-order when
 506      opening a new file, TARGET_BYTE_ORDER is normally correct. */
 507   if (TARGET_BYTE_ORDER == BIG_ENDIAN)
 508     strcat (arg_buf, " -E big");
 509   else
 510     strcat (arg_buf, " -E little");
 511 #endif
 512   argv = buildargv (arg_buf);
 513   if (argv == NULL)
 514     error ("Insufficient memory available to allocate simulator arg list.");
 515   make_cleanup (freeargv, (char *) argv);
 516
 517   init_callbacks ();
 518   gdbsim_desc = sim_open (SIM_OPEN_DEBUG, &gdb_callback, argv);
 519
 520   if (gdbsim_desc == 0)
 521     error ("unable to create simulator instance");
 522
 523   push_target (&gdbsim_ops);
 524   target_fetch_registers (-1);
 525   printf_filtered ("Connected to the simulator.\n");
 526 }
 527
 528 /* Does whatever cleanup is required for a target that we are no longer
 529    going to be calling.  Argument says whether we are quitting gdb and
 530    should not get hung in case of errors, or whether we want a clean
 531    termination even if it takes a while.  This routine is automatically
 532    always called just before a routine is popped off the target stack.
 533    Closing file descriptors and freeing memory are typical things it should
 534    do.  */
 535 /* Close out all files and local state before this target loses control. */
 536
 537 static void
 538 gdbsim_close (quitting)
 539      int quitting;
 540 {
 541   if (sr_get_debug ())
 542     printf_filtered ("gdbsim_close: quitting %d\n", quitting);
 543
 544   program_loaded = 0;
 545
 546   if (gdbsim_desc != NULL)
 547     {
 548       sim_close (gdbsim_desc, quitting);
 549       gdbsim_desc = NULL;
 550     }
 551
 552   end_callbacks ();
 553 }
 554
 555 /* Takes a program previously attached to and detaches it.
 556    The program may resume execution (some targets do, some don't) and will
 557    no longer stop on signals, etc.  We better not have left any breakpoints
 558    in the program or it'll die when it hits one.  ARGS is arguments
 559    typed by the user (e.g. a signal to send the process).  FROM_TTY
 560    says whether to be verbose or not.  */
 561 /* Terminate the open connection to the remote debugger.
 562    Use this when you want to detach and do something else with your gdb.  */
 563
 564 static void
 565 gdbsim_detach (args,from_tty)
 566      char *args;
 567      int from_tty;
 568 {
 569   if (sr_get_debug ())
 570     printf_filtered ("gdbsim_detach: args \"%s\"\n", args);
 571
 572   pop_target ();                /* calls gdbsim_close to do the real work */
 573   if (from_tty)
 574     printf_filtered ("Ending simulator %s debugging\n", target_shortname);
 575 }
 576
 577 /* Resume execution of the target process.  STEP says whether to single-step
 578    or to run free; SIGGNAL is the signal value (e.g. SIGINT) to be given
 579    to the target, or zero for no signal.  */
 580
 581 static enum target_signal resume_siggnal;
 582 static int resume_step;
 583
 584 static void
 585 gdbsim_resume (pid, step, siggnal)
 586      int pid, step;
 587      enum target_signal siggnal;
 588 {
 589   if (inferior_pid != 42)
 590     error ("The program is not being run.");
 591
 592   if (sr_get_debug ())
 593     printf_filtered ("gdbsim_resume: step %d, signal %d\n", step, siggnal);
 594
 595   resume_siggnal = siggnal;
 596   resume_step = step;
 597 }
 598
 599 /* Notify the simulator of an asynchronous request to stop.
 600
 601    The simulator shall ensure that the stop request is eventually
 602    delivered to the simulator.  If the call is made while the
 603    simulator is not running then the stop request is processed when
 604    the simulator is next resumed.
 605
 606    For simulators that do not support this operation, just abort */
 607
 608 static void
 609 gdbsim_stop ()
 610 {
 611   if (! sim_stop (gdbsim_desc))
 612     {
 613       quit ();
 614     }
 615 }
 616
 617 /* GDB version of os_poll_quit callback.
 618    Taken from gdb/util.c - should be in a library */
 619
 620 static int
 621 gdb_os_poll_quit (p)
 622      host_callback *p;
 623 {
 624   notice_quit ();
 625   if (quit_flag) /* gdb's idea of quit */
 626     {
 627       quit_flag = 0; /* we've stolen it */
 628       return 1;
 629     }
 630   else if (immediate_quit)
 631     {
 632       return 1;
 633     }
 634   return 0;
 635 }
 636
 637 /* Wait for inferior process to do something.  Return pid of child,
 638    or -1 in case of error; store status through argument pointer STATUS,
 639    just as `wait' would. */
 640
 641 static void
 642 gdbsim_cntrl_c (int signo)
 643 {
 644   gdbsim_stop ();
 645 }
 646
 647 static int
 648 gdbsim_wait (pid, status)
 649      int pid;
 650      struct target_waitstatus *status;
 651 {
 652   static RETSIGTYPE (*prev_sigint) ();
 653   int sigrc = 0;
 654   enum sim_stop reason = sim_running;
 655
 656   if (sr_get_debug ())
 657     printf_filtered ("gdbsim_wait\n");
 658
 659   prev_sigint = signal (SIGINT, gdbsim_cntrl_c);
 660   sim_resume (gdbsim_desc, resume_step,
 661               target_signal_to_host (resume_siggnal));
 662   signal (SIGINT, prev_sigint);
 663   resume_step = 0;
 664
 665   sim_stop_reason (gdbsim_desc, &reason, &sigrc);
 666
 667   switch (reason)
 668     {
 669     case sim_exited:
 670       status->kind = TARGET_WAITKIND_EXITED;
 671       status->value.integer = sigrc;
 672       break;
 673     case sim_stopped:
 674       switch (sigrc)
 675         {
 676         case SIGABRT:
 677           quit ();
 678           break;
 679         case SIGINT:
 680         case SIGTRAP:
 681         default:
 682           status->kind = TARGET_WAITKIND_STOPPED;
 683           /* The signal in sigrc is a host signal.  That probably
 684              should be fixed.  */
 685           status->value.sig = target_signal_from_host (sigrc);
 686           break;
 687         }
 688       break;
 689     case sim_signalled:
 690       status->kind = TARGET_WAITKIND_SIGNALLED;
 691       /* The signal in sigrc is a host signal.  That probably
 692          should be fixed.  */
 693       status->value.sig = target_signal_from_host (sigrc);
 694       break;
 695     case sim_running:
 696     case sim_polling:
 697       /* FIXME: Is this correct? */
 698       break;
 699     }
 700
 701   return inferior_pid;
 702 }
 703
 704 /* Get ready to modify the registers array.  On machines which store
 705    individual registers, this doesn't need to do anything.  On machines
 706    which store all the registers in one fell swoop, this makes sure
 707    that registers contains all the registers from the program being
 708    debugged.  */
 709
 710 static void
 711 gdbsim_prepare_to_store ()
 712 {
 713   /* Do nothing, since we can store individual regs */
 714 }
 715
 716 static int
 717 gdbsim_xfer_inferior_memory (memaddr, myaddr, len, write, target)
 718      CORE_ADDR memaddr;
 719      char *myaddr;
 720      int len;
 721      int write;
 722      struct target_ops *target;                 /* ignored */
 723 {
 724   if (! program_loaded)
 725     error ("No program loaded.");
 726
 727   if (sr_get_debug ())
 728     {
 729       printf_filtered ("gdbsim_xfer_inferior_memory: myaddr 0x%x, memaddr 0x%x, len %d, write %d\n",
 730                        myaddr, memaddr, len, write);
 731       if (sr_get_debug () && write)
 732         dump_mem(myaddr, len);
 733     }
 734
 735   if (write)
 736     {
 737       len = sim_write (gdbsim_desc, memaddr, myaddr, len);
 738     }
 739   else
 740     {
 741       len = sim_read (gdbsim_desc, memaddr, myaddr, len);
 742       if (sr_get_debug () && len > 0)
 743         dump_mem(myaddr, len);
 744     }
 745   return len;
 746 }
 747
 748 static void
 749 gdbsim_files_info (target)
 750      struct target_ops *target;
 751 {
 752   char *file = "nothing";
 753
 754   if (exec_bfd)
 755     file = bfd_get_filename (exec_bfd);
 756
 757   if (sr_get_debug ())
 758     printf_filtered ("gdbsim_files_info: file \"%s\"\n", file);
 759
 760   if (exec_bfd)
 761     {
 762       printf_filtered ("\tAttached to %s running program %s\n",
 763                        target_shortname, file);
 764       sim_info (gdbsim_desc, 0);
 765     }
 766 }
 767
 768 /* Clear the simulator's notion of what the break points are.  */
 769
 770 static void
 771 gdbsim_mourn_inferior ()
 772 {
 773   if (sr_get_debug ())
 774     printf_filtered ("gdbsim_mourn_inferior:\n");
 775
 776   remove_breakpoints ();
 777   generic_mourn_inferior ();
 778 }
 779
 780 /* Pass the command argument through to the simulator verbatim.  The
 781    simulator must do any command interpretation work.  */
 782
 783 static void
 784 simulator_command (args, from_tty)
 785      char *args;
 786      int from_tty;
 787 {
 788   if (gdbsim_desc == NULL)
 789     {
 790
 791       /* PREVIOUSLY: The user may give a command before the simulator
 792          is opened. [...] (??? assuming of course one wishes to
 793          continue to allow commands to be sent to unopened simulators,
 794          which isn't entirely unreasonable). */
 795
 796       /* The simulator is a builtin abstraction of a remote target.
 797          Consistent with that model, access to the simulator, via sim
 798          commands, is restricted to the period when the channel to the
 799          simulator is open. */
 800
 801       error ("Not connected to the simulator target");
 802     }
 803
 804   sim_do_command (gdbsim_desc, args);
 805 }
 806
 807 /* Define the target subroutine names */
 808
 809 struct target_ops gdbsim_ops = {
 810   "sim",                        /* to_shortname */
 811   "simulator",                  /* to_longname */
 812   "Use the compiled-in simulator.",  /* to_doc */
 813   gdbsim_open,                  /* to_open */
 814   gdbsim_close,                 /* to_close */
 815   NULL,                         /* to_attach */
 816   gdbsim_detach,                /* to_detach */
 817   gdbsim_resume,                /* to_resume */
 818   gdbsim_wait,                  /* to_wait */
 819   gdbsim_fetch_register,        /* to_fetch_registers */
 820   gdbsim_store_register,        /* to_store_registers */
 821   gdbsim_prepare_to_store,      /* to_prepare_to_store */
 822   gdbsim_xfer_inferior_memory,  /* to_xfer_memory */
 823   gdbsim_files_info,            /* to_files_info */
 824   memory_insert_breakpoint,     /* to_insert_breakpoint */
 825   memory_remove_breakpoint,     /* to_remove_breakpoint */
 826   NULL,                         /* to_terminal_init */
 827   NULL,                         /* to_terminal_inferior */
 828   NULL,                         /* to_terminal_ours_for_output */
 829   NULL,                         /* to_terminal_ours */
 830   NULL,                         /* to_terminal_info */
 831   gdbsim_kill,                  /* to_kill */
 832   gdbsim_load,                  /* to_load */
 833   NULL,                         /* to_lookup_symbol */
 834   gdbsim_create_inferior,       /* to_create_inferior */
 835   gdbsim_mourn_inferior,        /* to_mourn_inferior */
 836   0,                            /* to_can_run */
 837   0,                            /* to_notice_signals */
 838   0,                            /* to_thread_alive */
 839   gdbsim_stop,                  /* to_stop */
 840   process_stratum,              /* to_stratum */
 841   NULL,                         /* to_next */
 842   1,                            /* to_has_all_memory */
 843   1,                            /* to_has_memory */
 844   1,                            /* to_has_stack */
 845   1,                            /* to_has_registers */
 846   1,                            /* to_has_execution */
 847   NULL,                         /* sections */
 848   NULL,                         /* sections_end */
 849   OPS_MAGIC,                    /* to_magic */
 850 };
 851
 852 void
 853 _initialize_remote_sim ()
 854 {
 855   add_target (&gdbsim_ops);
 856
 857   add_com ("sim <command>", class_obscure, simulator_command,
 858            "Send a command to the simulator.");
 859 }