gdb/remote-sim.c - gdb

Global variables defined

Data types defined

Functions defined

Macros defined

Source code

  1. /* Generic remote debugging interface for simulators.

  3.    Copyright (C) 1993-2015 Free Software Foundation, Inc.

  5.    Contributed by Cygnus Support.
  6.    Steve Chamberlain (sac@cygnus.com).

  8.    This file is part of GDB.

  10.    This program is free software; you can redistribute it and/or modify
  11.    it under the terms of the GNU General Public License as published by
  12.    the Free Software Foundation; either version 3 of the License, or
  13.    (at your option) any later version.

  15.    This program is distributed in the hope that it will be useful,
  16.    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17.    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18.    GNU General Public License for more details.

  20.    You should have received a copy of the GNU General Public License
  21.    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

  23. #include "defs.h"
  24. #include "inferior.h"
  25. #include "infrun.h"
  26. #include "value.h"
  27. #include <ctype.h>
  28. #include <fcntl.h>
  29. #include <signal.h>
  30. #include <setjmp.h>
  31. #include "terminal.h"
  32. #include "target.h"
  33. #include "gdbcore.h"
  34. #include "gdb/callback.h"
  35. #include "gdb/remote-sim.h"
  36. #include "command.h"
  37. #include "regcache.h"
  38. #include "sim-regno.h"
  39. #include "arch-utils.h"
  40. #include "readline/readline.h"
  41. #include "gdbthread.h"

  43. /* Prototypes */

  45. extern void _initialize_remote_sim (void);

  47. static void init_callbacks (void);

  49. static void end_callbacks (void);

  51. static int gdb_os_write_stdout (host_callback *, const char *, int);

  53. static void gdb_os_flush_stdout (host_callback *);

  55. static int gdb_os_write_stderr (host_callback *, const char *, int);

  57. static void gdb_os_flush_stderr (host_callback *);

  59. static int gdb_os_poll_quit (host_callback *);

  61. /* printf_filtered is depreciated.  */
  62. static void gdb_os_printf_filtered (host_callback *, const char *, ...);

  64. static void gdb_os_vprintf_filtered (host_callback *, const char *, va_list);

  66. static void gdb_os_evprintf_filtered (host_callback *, const char *, va_list);

  68. static void gdb_os_error (host_callback *, const char *, ...)
  69.      ATTRIBUTE_NORETURN;

  71. static void gdbsim_kill (struct target_ops *);

  73. static void gdbsim_load (struct target_ops *self, const char *prog,
  74.                          int fromtty);

  76. static void gdbsim_open (const char *args, int from_tty);

  78. static void gdbsim_close (struct target_ops *self);

  80. static void gdbsim_detach (struct target_ops *ops, const char *args,
  81.                            int from_tty);

  83. static void gdbsim_prepare_to_store (struct target_ops *self,
  84.                                      struct regcache *regcache);

  86. static void gdbsim_files_info (struct target_ops *target);

  88. static void gdbsim_mourn_inferior (struct target_ops *target);

  90. static void gdbsim_stop (struct target_ops *self, ptid_t ptid);

  92. void simulator_command (char *args, int from_tty);

  94. /* Naming convention:

  96.    sim_* are the interface to the simulator (see remote-sim.h).
  97.    gdbsim_* are stuff which is internal to gdb.  */

  99. /* Forward data declarations */
  100. extern struct target_ops gdbsim_ops;

  102. ‌static const struct inferior_data *sim_inferior_data_key;

  104. /* Simulator-specific, per-inferior state.  */
  105. ‌struct sim_inferior_data {
  106.   /* Flag which indicates whether or not the program has been loaded.  */
  107.   int program_loaded;

  109.   /* Simulator descriptor for this inferior.  */
  110.   SIM_DESC gdbsim_desc;

  112.   /* This is the ptid we use for this particular simulator instance.  Its
  113.      value is somewhat arbitrary, as the simulator target don't have a
  114.      notion of tasks or threads, but we need something non-null to place
  115.      in inferior_ptid.  For simulators which permit multiple instances,
  116.      we also need a unique identifier to use for each inferior.  */
  117.   ptid_t remote_sim_ptid;

  119.   /* Signal with which to resume.  */
  120.   enum gdb_signal resume_siggnal;

  122.   /* Flag which indicates whether resume should step or not.  */
  123.   int resume_step;
  124. };

  126. /* Flag indicating the "open" status of this module.  It's set to 1
  127.    in gdbsim_open() and 0 in gdbsim_close().  */
  128. ‌static int gdbsim_is_open = 0;

  130. /* Value of the next pid to allocate for an inferior.  As indicated
  131.    elsewhere, its initial value is somewhat arbitrary; it's critical
  132.    though that it's not zero or negative.  */
  133. ‌static int next_pid;
  134. ‌#define INITIAL_PID 42000

  136. /* Argument list to pass to sim_open().  It is allocated in gdbsim_open()
  137.    and deallocated in gdbsim_close().  The lifetime needs to extend beyond
  138.    the call to gdbsim_open() due to the fact that other sim instances other
  139.    than the first will be allocated after the gdbsim_open() call.  */
  140. ‌static char **sim_argv = NULL;

  142. /* OS-level callback functions for write, flush, etc.  */
  143. ‌static host_callback gdb_callback;
  144. ‌static int callbacks_initialized = 0;

  146. /* Callback for iterate_over_inferiors.  It checks to see if the sim
  147.    descriptor passed via ARG is the same as that for the inferior
  148.    designated by INF.  Return true if so; false otherwise.  */

  150. static int
  151. ‌check_for_duplicate_sim_descriptor (struct inferior *inf, void *arg)
  152. {
  153.   struct sim_inferior_data *sim_data;
  154.   SIM_DESC new_sim_desc = arg;

  156.   sim_data = inferior_data (inf, sim_inferior_data_key);

  158.   return (sim_data != NULL && sim_data->gdbsim_desc == new_sim_desc);
  159. }

  161. /* Flags indicating whether or not a sim instance is needed.  One of these
  162.    flags should be passed to get_sim_inferior_data().  */

  164. enum {SIM_INSTANCE_NOT_NEEDED = 0, SIM_INSTANCE_NEEDED = 1};

  166. /* Obtain pointer to per-inferior simulator data, allocating it if necessary.
  167.    Attempt to open the sim if SIM_INSTANCE_NEEDED is true.  */

  169. static struct sim_inferior_data *
  170. ‌get_sim_inferior_data (struct inferior *inf, int sim_instance_needed)
  171. {
  172.   SIM_DESC sim_desc = NULL;
  173.   struct sim_inferior_data *sim_data
  174.     = inferior_data (inf, sim_inferior_data_key);

  176.   /* Try to allocate a new sim instance, if needed.  We do this ahead of
  177.      a potential allocation of a sim_inferior_data struct in order to
  178.      avoid needlessly allocating that struct in the event that the sim
  179.      instance allocation fails.  */
  180.   if (sim_instance_needed == SIM_INSTANCE_NEEDED
  181.       && (sim_data == NULL || sim_data->gdbsim_desc == NULL))
  182.     {
  183.       struct inferior *idup;
  184.       sim_desc = sim_open (SIM_OPEN_DEBUG, &gdb_callback, exec_bfd, sim_argv);
  185.       if (sim_desc == NULL)
  186.         error (_("Unable to create simulator instance for inferior %d."),
  187.                inf->num);

  189.       idup = iterate_over_inferiors (check_for_duplicate_sim_descriptor,
  190.                                      sim_desc);
  191.       if (idup != NULL)
  192.         {
  193.           /* We don't close the descriptor due to the fact that it's
  194.              shared with some other inferior.  If we were to close it,
  195.              that might needlessly muck up the other inferior.  Of
  196.              course, it's possible that the damage has already been
  197.              done...  Note that it *will* ultimately be closed during
  198.              cleanup of the other inferior.  */
  199.           sim_desc = NULL;
  200.           error (
  201. _("Inferior %d and inferior %d would have identical simulator state.\n"
  202.    "(This simulator does not support the running of more than one inferior.)"),
  203.                  inf->num, idup->num);
  204.         }
  205.     }

  207.   if (sim_data == NULL)
  208.     {
  209.       sim_data = XCNEW(struct sim_inferior_data);
  210.       set_inferior_data (inf, sim_inferior_data_key, sim_data);

  212.       /* Allocate a ptid for this inferior.  */
  213.       sim_data->remote_sim_ptid = ptid_build (next_pid, 0, next_pid);
  214.       next_pid++;

  216.       /* Initialize the other instance variables.  */
  217.       sim_data->program_loaded = 0;
  218.       sim_data->gdbsim_desc = sim_desc;
  219.       sim_data->resume_siggnal = GDB_SIGNAL_0;
  220.       sim_data->resume_step = 0;
  221.     }
  222.   else if (sim_desc)
  223.     {
  224.       /* This handles the case where sim_data was allocated prior to
  225.          needing a sim instance.  */
  226.       sim_data->gdbsim_desc = sim_desc;
  227.     }


  230.   return sim_data;
  231. }

  233. /* Return pointer to per-inferior simulator data using PTID to find the
  234.    inferior in question.  Return NULL when no inferior is found or
  235.    when ptid has a zero or negative pid component.  */

  237. static struct sim_inferior_data *
  238. ‌get_sim_inferior_data_by_ptid (ptid_t ptid, int sim_instance_needed)
  239. {
  240.   struct inferior *inf;
  241.   int pid = ptid_get_pid (ptid);

  243.   if (pid <= 0)
  244.     return NULL;

  246.   inf = find_inferior_pid (pid);

  248.   if (inf)
  249.     return get_sim_inferior_data (inf, sim_instance_needed);
  250.   else
  251.     return NULL;
  252. }

  254. /* Free the per-inferior simulator data.  */

  256. static void
  257. ‌sim_inferior_data_cleanup (struct inferior *inf, void *data)
  258. {
  259.   struct sim_inferior_data *sim_data = data;

  261.   if (sim_data != NULL)
  262.     {
  263.       if (sim_data->gdbsim_desc)
  264.         {
  265.           sim_close (sim_data->gdbsim_desc, 0);
  266.           sim_data->gdbsim_desc = NULL;
  267.         }
  268.       xfree (sim_data);
  269.     }
  270. }

  272. static void
  273. ‌dump_mem (const gdb_byte *buf, int len)
  274. {
  275.   fputs_unfiltered ("\t", gdb_stdlog);

  277.   if (len == 8 || len == 4)
  278.     {
  279.       uint32_t l[2];

  281.       memcpy (l, buf, len);
  282.       fprintf_unfiltered (gdb_stdlog, "0x%08x", l[0]);
  283.       if (len == 8)
  284.         fprintf_unfiltered (gdb_stdlog, " 0x%08x", l[1]);
  285.     }
  286.   else
  287.     {
  288.       int i;

  290.       for (i = 0; i < len; i++)
  291.         fprintf_unfiltered (gdb_stdlog, "0x%02x ", buf[i]);
  292.     }

  294.   fputs_unfiltered ("\n", gdb_stdlog);
  295. }

  297. /* Initialize gdb_callback.  */

  299. static void
  300. ‌init_callbacks (void)
  301. {
  302.   if (!callbacks_initialized)
  303.     {
  304.       gdb_callback = default_callback;
  305.       gdb_callback.init (&gdb_callback);
  306.       gdb_callback.write_stdout = gdb_os_write_stdout;
  307.       gdb_callback.flush_stdout = gdb_os_flush_stdout;
  308.       gdb_callback.write_stderr = gdb_os_write_stderr;
  309.       gdb_callback.flush_stderr = gdb_os_flush_stderr;
  310.       gdb_callback.printf_filtered = gdb_os_printf_filtered;
  311.       gdb_callback.vprintf_filtered = gdb_os_vprintf_filtered;
  312.       gdb_callback.evprintf_filtered = gdb_os_evprintf_filtered;
  313.       gdb_callback.error = gdb_os_error;
  314.       gdb_callback.poll_quit = gdb_os_poll_quit;
  315.       gdb_callback.magic = HOST_CALLBACK_MAGIC;
  316.       callbacks_initialized = 1;
  317.     }
  318. }

  320. /* Release callbacks (free resources used by them).  */

  322. static void
  323. ‌end_callbacks (void)
  324. {
  325.   if (callbacks_initialized)
  326.     {
  327.       gdb_callback.shutdown (&gdb_callback);
  328.       callbacks_initialized = 0;
  329.     }
  330. }

  332. /* GDB version of os_write_stdout callback.  */

  334. static int
  335. ‌gdb_os_write_stdout (host_callback *p, const char *buf, int len)
  336. {
  337.   int i;
  338.   char b[2];

  340.   ui_file_write (gdb_stdtarg, buf, len);
  341.   return len;
  342. }

  344. /* GDB version of os_flush_stdout callback.  */

  346. static void
  347. ‌gdb_os_flush_stdout (host_callback *p)
  348. {
  349.   gdb_flush (gdb_stdtarg);
  350. }

  352. /* GDB version of os_write_stderr callback.  */

  354. static int
  355. ‌gdb_os_write_stderr (host_callback *p, const char *buf, int len)
  356. {
  357.   int i;
  358.   char b[2];

  360.   for (i = 0; i < len; i++)
  361.     {
  362.       b[0] = buf[i];
  363.       b[1] = 0;
  364.       fputs_unfiltered (b, gdb_stdtargerr);
  365.     }
  366.   return len;
  367. }

  369. /* GDB version of os_flush_stderr callback.  */

  371. static void
  372. ‌gdb_os_flush_stderr (host_callback *p)
  373. {
  374.   gdb_flush (gdb_stdtargerr);
  375. }

  377. /* GDB version of printf_filtered callback.  */

  379. static void
  380. ‌gdb_os_printf_filtered (host_callback * p, const char *format,...)
  381. {
  382.   va_list args;

  384.   va_start (args, format);
  385.   vfprintf_filtered (gdb_stdout, format, args);
  386.   va_end (args);
  387. }

  389. /* GDB version of error vprintf_filtered.  */

  391. static void
  392. ‌gdb_os_vprintf_filtered (host_callback * p, const char *format, va_list ap)
  393. {
  394.   vfprintf_filtered (gdb_stdout, format, ap);
  395. }

  397. /* GDB version of error evprintf_filtered.  */

  399. static void
  400. ‌gdb_os_evprintf_filtered (host_callback * p, const char *format, va_list ap)
  401. {
  402.   vfprintf_filtered (gdb_stderr, format, ap);
  403. }

  405. /* GDB version of error callback.  */

  407. static void
  408. ‌gdb_os_error (host_callback * p, const char *format, ...)
  409. {
  410.   va_list args;

  412.   va_start (args, format);
  413.   verror (format, args);
  414.   va_end (args);
  415. }

  417. int
  418. ‌one2one_register_sim_regno (struct gdbarch *gdbarch, int regnum)
  419. {
  420.   /* Only makes sense to supply raw registers.  */
  421.   gdb_assert (regnum >= 0 && regnum < gdbarch_num_regs (gdbarch));
  422.   return regnum;
  423. }

  425. static void
  426. ‌gdbsim_fetch_register (struct target_ops *ops,
  427.                        struct regcache *regcache, int regno)
  428. {
  429.   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  430.   struct sim_inferior_data *sim_data
  431.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);

  433.   if (regno == -1)
  434.     {
  435.       for (regno = 0; regno < gdbarch_num_regs (gdbarch); regno++)
  436.         gdbsim_fetch_register (ops, regcache, regno);
  437.       return;
  438.     }

  440.   switch (gdbarch_register_sim_regno (gdbarch, regno))
  441.     {
  442.     case LEGACY_SIM_REGNO_IGNORE:
  443.       break;
  444.     case SIM_REGNO_DOES_NOT_EXIST:
  445.       {
  446.         /* For moment treat a `does not exist' register the same way
  447.            as an ``unavailable'' register.  */
  448.         gdb_byte buf[MAX_REGISTER_SIZE];
  449.         int nr_bytes;

  451.         memset (buf, 0, MAX_REGISTER_SIZE);
  452.         regcache_raw_supply (regcache, regno, buf);
  453.         break;
  454.       }

  456.     default:
  457.       {
  458.         static int warn_user = 1;
  459.         gdb_byte buf[MAX_REGISTER_SIZE];
  460.         int nr_bytes;

  462.         gdb_assert (regno >= 0 && regno < gdbarch_num_regs (gdbarch));
  463.         memset (buf, 0, MAX_REGISTER_SIZE);
  464.         nr_bytes = sim_fetch_register (sim_data->gdbsim_desc,
  465.                                        gdbarch_register_sim_regno
  466.                                          (gdbarch, regno),
  467.                                        buf,
  468.                                        register_size (gdbarch, regno));
  469.         if (nr_bytes > 0
  470.             && nr_bytes != register_size (gdbarch, regno) && warn_user)
  471.           {
  472.             fprintf_unfiltered (gdb_stderr,
  473.                                 "Size of register %s (%d/%d) "
  474.                                 "incorrect (%d instead of %d))",
  475.                                 gdbarch_register_name (gdbarch, regno),
  476.                                 regno,
  477.                                 gdbarch_register_sim_regno
  478.                                   (gdbarch, regno),
  479.                                 nr_bytes, register_size (gdbarch, regno));
  480.             warn_user = 0;
  481.           }
  482.         /* FIXME: cagney/2002-05-27: Should check `nr_bytes == 0'
  483.            indicating that GDB and the SIM have different ideas about
  484.            which registers are fetchable.  */
  485.         /* Else if (nr_bytes < 0): an old simulator, that doesn't
  486.            think to return the register size.  Just assume all is ok.  */
  487.         regcache_raw_supply (regcache, regno, buf);
  488.         if (remote_debug)
  489.           {
  490.             fprintf_unfiltered (gdb_stdlog,
  491.                                 "gdbsim_fetch_register: %d", regno);
  492.             /* FIXME: We could print something more intelligible.  */
  493.             dump_mem (buf, register_size (gdbarch, regno));
  494.           }
  495.         break;
  496.       }
  497.     }
  498. }


  501. static void
  502. ‌gdbsim_store_register (struct target_ops *ops,
  503.                        struct regcache *regcache, int regno)
  504. {
  505.   struct gdbarch *gdbarch = get_regcache_arch (regcache);
  506.   struct sim_inferior_data *sim_data
  507.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);

  509.   if (regno == -1)
  510.     {
  511.       for (regno = 0; regno < gdbarch_num_regs (gdbarch); regno++)
  512.         gdbsim_store_register (ops, regcache, regno);
  513.       return;
  514.     }
  515.   else if (gdbarch_register_sim_regno (gdbarch, regno) >= 0)
  516.     {
  517.       gdb_byte tmp[MAX_REGISTER_SIZE];
  518.       int nr_bytes;

  520.       regcache_cooked_read (regcache, regno, tmp);
  521.       nr_bytes = sim_store_register (sim_data->gdbsim_desc,
  522.                                      gdbarch_register_sim_regno
  523.                                        (gdbarch, regno),
  524.                                      tmp, register_size (gdbarch, regno));
  525.       if (nr_bytes > 0 && nr_bytes != register_size (gdbarch, regno))
  526.         internal_error (__FILE__, __LINE__,
  527.                         _("Register size different to expected"));
  528.       if (nr_bytes < 0)
  529.         internal_error (__FILE__, __LINE__,
  530.                         _("Register %d not updated"), regno);
  531.       if (nr_bytes == 0)
  532.         warning (_("Register %s not updated"),
  533.                  gdbarch_register_name (gdbarch, regno));

  535.       if (remote_debug)
  536.         {
  537.           fprintf_unfiltered (gdb_stdlog, "gdbsim_store_register: %d", regno);
  538.           /* FIXME: We could print something more intelligible.  */
  539.           dump_mem (tmp, register_size (gdbarch, regno));
  540.         }
  541.     }
  542. }

  544. /* Kill the running program.  This may involve closing any open files
  545.    and releasing other resources acquired by the simulated program.  */

  547. static void
  548. ‌gdbsim_kill (struct target_ops *ops)
  549. {
  550.   if (remote_debug)
  551.     fprintf_unfiltered (gdb_stdlog, "gdbsim_kill\n");

  553.   /* There is no need to `kill' running simulator - the simulator is
  554.      not running.  Mourning it is enough.  */
  555.   target_mourn_inferior ();
  556. }

  558. /* Load an executable file into the target process.  This is expected to
  559.    not only bring new code into the target process, but also to update
  560.    GDB's symbol tables to match.  */

  562. static void
  563. ‌gdbsim_load (struct target_ops *self, const char *args, int fromtty)
  564. {
  565.   char **argv;
  566.   const char *prog;
  567.   struct sim_inferior_data *sim_data
  568.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);

  570.   if (args == NULL)
  571.       error_no_arg (_("program to load"));

  573.   argv = gdb_buildargv (args);
  574.   make_cleanup_freeargv (argv);

  576.   prog = tilde_expand (argv[0]);

  578.   if (argv[1] != NULL)
  579.     error (_("GDB sim does not yet support a load offset."));

  581.   if (remote_debug)
  582.     fprintf_unfiltered (gdb_stdlog, "gdbsim_load: prog \"%s\"\n", prog);

  584.   /* FIXME: We will print two messages on error.
  585.      Need error to either not print anything if passed NULL or need
  586.      another routine that doesn't take any arguments.  */
  587.   if (sim_load (sim_data->gdbsim_desc, prog, NULL, fromtty) == SIM_RC_FAIL)
  588.     error (_("unable to load program"));

  590.   /* FIXME: If a load command should reset the targets registers then
  591.      a call to sim_create_inferior() should go here.  */

  593.   sim_data->program_loaded = 1;
  594. }


  597. /* Start an inferior process and set inferior_ptid to its pid.
  598.    EXEC_FILE is the file to run.
  599.    ARGS is a string containing the arguments to the program.
  600.    ENV is the environment vector to pass.  Errors reported with error().
  601.    On VxWorks and various standalone systems, we ignore exec_file.  */
  602. /* This is called not only when we first attach, but also when the
  603.    user types "run" after having attached.  */

  605. static void
  606. ‌gdbsim_create_inferior (struct target_ops *target, char *exec_file, char *args,
  607.                         char **env, int from_tty)
  608. {
  609.   struct sim_inferior_data *sim_data
  610.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);
  611.   int len;
  612.   char *arg_buf, **argv;

  614.   if (exec_file == 0 || exec_bfd == 0)
  615.     warning (_("No executable file specified."));
  616.   if (!sim_data->program_loaded)
  617.     warning (_("No program loaded."));

  619.   if (remote_debug)
  620.     fprintf_unfiltered (gdb_stdlog,
  621.                         "gdbsim_create_inferior: exec_file \"%s\", args \"%s\"\n",
  622.                         (exec_file ? exec_file : "(NULL)"),
  623.                         args);

  625.   if (ptid_equal (inferior_ptid, sim_data->remote_sim_ptid))
  626.     gdbsim_kill (target);
  627.   remove_breakpoints ();
  628.   init_wait_for_inferior ();

  630.   if (exec_file != NULL)
  631.     {
  632.       len = strlen (exec_file) + 1 + strlen (args) + 1 + /*slop */ 10;
  633.       arg_buf = (char *) alloca (len);
  634.       arg_buf[0] = '\0';
  635.       strcat (arg_buf, exec_file);
  636.       strcat (arg_buf, " ");
  637.       strcat (arg_buf, args);
  638.       argv = gdb_buildargv (arg_buf);
  639.       make_cleanup_freeargv (argv);
  640.     }
  641.   else
  642.     argv = NULL;

  644.   if (!have_inferiors ())
  645.     init_thread_list ();

  647.   if (sim_create_inferior (sim_data->gdbsim_desc, exec_bfd, argv, env)
  648.       != SIM_RC_OK)
  649.     error (_("Unable to create sim inferior."));

  651.   inferior_ptid = sim_data->remote_sim_ptid;
  652.   inferior_appeared (current_inferior (), ptid_get_pid (inferior_ptid));
  653.   add_thread_silent (inferior_ptid);

  655.   insert_breakpoints ();        /* Needed to get correct instruction
  656.                                    in cache.  */

  658.   clear_proceed_status (0);
  659. }

  661. /* The open routine takes the rest of the parameters from the command,
  662.    and (if successful) pushes a new target onto the stack.
  663.    Targets should supply this routine, if only to provide an error message.  */
  664. /* Called when selecting the simulator.  E.g. (gdb) target sim name.  */

  666. static void
  667. ‌gdbsim_open (const char *args, int from_tty)
  668. {
  669.   int len;
  670.   char *arg_buf;
  671.   struct sim_inferior_data *sim_data;
  672.   SIM_DESC gdbsim_desc;

  674.   if (remote_debug)
  675.     fprintf_unfiltered (gdb_stdlog,
  676.                         "gdbsim_open: args \"%s\"\n", args ? args : "(null)");

  678.   /* Ensure that the sim target is not on the target stack.  This is
  679.      necessary, because if it is on the target stack, the call to
  680.      push_target below will invoke sim_close(), thus freeing various
  681.      state (including a sim instance) that we allocate prior to
  682.      invoking push_target().  We want to delay the push_target()
  683.      operation until after we complete those operations which could
  684.      error out.  */
  685.   if (gdbsim_is_open)
  686.     unpush_target (&gdbsim_ops);

  688.   len = (7 + 1                        /* gdbsim */
  689.          + strlen (" -E little")
  690.          + strlen (" --architecture=xxxxxxxxxx")
  691.          + strlen (" --sysroot=") + strlen (gdb_sysroot) +
  692.          + (args ? strlen (args) : 0)
  693.          + 50) /* slack */ ;
  694.   arg_buf = (char *) alloca (len);
  695.   strcpy (arg_buf, "gdbsim");        /* 7 */
  696.   /* Specify the byte order for the target when it is explicitly
  697.      specified by the user (not auto detected).  */
  698.   switch (selected_byte_order ())
  699.     {
  700.     case BFD_ENDIAN_BIG:
  701.       strcat (arg_buf, " -E big");
  702.       break;
  703.     case BFD_ENDIAN_LITTLE:
  704.       strcat (arg_buf, " -E little");
  705.       break;
  706.     case BFD_ENDIAN_UNKNOWN:
  707.       break;
  708.     }
  709.   /* Specify the architecture of the target when it has been
  710.      explicitly specified */
  711.   if (selected_architecture_name () != NULL)
  712.     {
  713.       strcat (arg_buf, " --architecture=");
  714.       strcat (arg_buf, selected_architecture_name ());
  715.     }
  716.   /* Pass along gdb's concept of the sysroot.  */
  717.   strcat (arg_buf, " --sysroot=");
  718.   strcat (arg_buf, gdb_sysroot);
  719.   /* finally, any explicit args */
  720.   if (args)
  721.     {
  722.       strcat (arg_buf, " ");        /* 1 */
  723.       strcat (arg_buf, args);
  724.     }
  725.   sim_argv = gdb_buildargv (arg_buf);

  727.   init_callbacks ();
  728.   gdbsim_desc = sim_open (SIM_OPEN_DEBUG, &gdb_callback, exec_bfd, sim_argv);

  730.   if (gdbsim_desc == 0)
  731.     {
  732.       freeargv (sim_argv);
  733.       sim_argv = NULL;
  734.       error (_("unable to create simulator instance"));
  735.     }

  737.   /* Reset the pid numberings for this batch of sim instances.  */
  738.   next_pid = INITIAL_PID;

  740.   /* Allocate the inferior data, but do not allocate a sim instance
  741.      since we've already just done that.  */
  742.   sim_data = get_sim_inferior_data (current_inferior (),
  743.                                     SIM_INSTANCE_NOT_NEEDED);

  745.   sim_data->gdbsim_desc = gdbsim_desc;

  747.   push_target (&gdbsim_ops);
  748.   printf_filtered ("Connected to the simulator.\n");

  750.   /* There's nothing running after "target sim" or "load"; not until
  751.      "run".  */
  752.   inferior_ptid = null_ptid;

  754.   gdbsim_is_open = 1;
  755. }

  757. /* Callback for iterate_over_inferiors.  Called (indirectly) by
  758.    gdbsim_close().  */

  760. static int
  761. ‌gdbsim_close_inferior (struct inferior *inf, void *arg)
  762. {
  763.   struct sim_inferior_data *sim_data = inferior_data (inf,
  764.                                                       sim_inferior_data_key);
  765.   if (sim_data != NULL)
  766.     {
  767.       ptid_t ptid = sim_data->remote_sim_ptid;

  769.       sim_inferior_data_cleanup (inf, sim_data);
  770.       set_inferior_data (inf, sim_inferior_data_key, NULL);

  772.       /* Having a ptid allocated and stored in remote_sim_ptid does
  773.          not mean that a corresponding inferior was ever created.
  774.          Thus we need to verify the existence of an inferior using the
  775.          pid in question before setting inferior_ptid via
  776.          switch_to_thread() or mourning the inferior.  */
  777.       if (find_inferior_ptid (ptid) != NULL)
  778.         {
  779.           switch_to_thread (ptid);
  780.           generic_mourn_inferior ();
  781.         }
  782.     }

  784.   return 0;
  785. }

  787. /* Close out all files and local state before this target loses control.  */

  789. static void
  790. ‌gdbsim_close (struct target_ops *self)
  791. {
  792.   struct sim_inferior_data *sim_data
  793.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);

  795.   if (remote_debug)
  796.     fprintf_unfiltered (gdb_stdlog, "gdbsim_close\n");

  798.   iterate_over_inferiors (gdbsim_close_inferior, NULL);

  800.   if (sim_argv != NULL)
  801.     {
  802.       freeargv (sim_argv);
  803.       sim_argv = NULL;
  804.     }

  806.   end_callbacks ();

  808.   gdbsim_is_open = 0;
  809. }

  811. /* Takes a program previously attached to and detaches it.
  812.    The program may resume execution (some targets do, some don't) and will
  813.    no longer stop on signals, etc.  We better not have left any breakpoints
  814.    in the program or it'll die when it hits one.  ARGS is arguments
  815.    typed by the user (e.g. a signal to send the process).  FROM_TTY
  816.    says whether to be verbose or not.  */
  817. /* Terminate the open connection to the remote debugger.
  818.    Use this when you want to detach and do something else with your gdb.  */

  820. static void
  821. ‌gdbsim_detach (struct target_ops *ops, const char *args, int from_tty)
  822. {
  823.   if (remote_debug)
  824.     fprintf_unfiltered (gdb_stdlog, "gdbsim_detach: args \"%s\"\n", args);

  826.   unpush_target (ops);                /* calls gdbsim_close to do the real work */
  827.   if (from_tty)
  828.     printf_filtered ("Ending simulator %s debugging\n", target_shortname);
  829. }

  831. /* Resume execution of the target process.  STEP says whether to single-step
  832.    or to run free; SIGGNAL is the signal value (e.g. SIGINT) to be given
  833.    to the target, or zero for no signal.  */

  835. ‌struct resume_data
  836. {
  837.   enum gdb_signal siggnal;
  838.   int step;
  839. };

  841. static int
  842. ‌gdbsim_resume_inferior (struct inferior *inf, void *arg)
  843. {
  844.   struct sim_inferior_data *sim_data
  845.     = get_sim_inferior_data (inf, SIM_INSTANCE_NOT_NEEDED);
  846.   struct resume_data *rd = arg;

  848.   if (sim_data)
  849.     {
  850.       sim_data->resume_siggnal = rd->siggnal;
  851.       sim_data->resume_step = rd->step;

  853.       if (remote_debug)
  854.         fprintf_unfiltered (gdb_stdlog,
  855.                             _("gdbsim_resume: pid %d, step %d, signal %d\n"),
  856.                             inf->pid, rd->step, rd->siggnal);
  857.     }

  859.   /* When called from iterate_over_inferiors, a zero return causes the
  860.      iteration process to proceed until there are no more inferiors to
  861.      consider.  */
  862.   return 0;
  863. }

  865. static void
  866. ‌gdbsim_resume (struct target_ops *ops,
  867.                ptid_t ptid, int step, enum gdb_signal siggnal)
  868. {
  869.   struct resume_data rd;
  870.   struct sim_inferior_data *sim_data
  871.     = get_sim_inferior_data_by_ptid (ptid, SIM_INSTANCE_NOT_NEEDED);

  873.   rd.siggnal = siggnal;
  874.   rd.step = step;

  876.   /* We don't access any sim_data members within this function.
  877.      What's of interest is whether or not the call to
  878.      get_sim_inferior_data_by_ptid(), above, is able to obtain a
  879.      non-NULL pointer.  If it managed to obtain a non-NULL pointer, we
  880.      know we have a single inferior to consider.  If it's NULL, we
  881.      either have multiple inferiors to resume or an error condition.  */

  883.   if (sim_data)
  884.     gdbsim_resume_inferior (find_inferior_ptid (ptid), &rd);
  885.   else if (ptid_equal (ptid, minus_one_ptid))
  886.     iterate_over_inferiors (gdbsim_resume_inferior, &rd);
  887.   else
  888.     error (_("The program is not being run."));
  889. }

  891. /* Notify the simulator of an asynchronous request to stop.

  893.    The simulator shall ensure that the stop request is eventually
  894.    delivered to the simulator.  If the call is made while the
  895.    simulator is not running then the stop request is processed when
  896.    the simulator is next resumed.

  898.    For simulators that do not support this operation, just abort.  */

  900. static int
  901. ‌gdbsim_stop_inferior (struct inferior *inf, void *arg)
  902. {
  903.   struct sim_inferior_data *sim_data
  904.     = get_sim_inferior_data (inf, SIM_INSTANCE_NEEDED);

  906.   if (sim_data)
  907.     {
  908.       if (!sim_stop (sim_data->gdbsim_desc))
  909.         {
  910.           quit ();
  911.         }
  912.     }

  914.   /* When called from iterate_over_inferiors, a zero return causes the
  915.      iteration process to proceed until there are no more inferiors to
  916.      consider.  */
  917.   return 0;
  918. }

  920. static void
  921. ‌gdbsim_stop (struct target_ops *self, ptid_t ptid)
  922. {
  923.   struct sim_inferior_data *sim_data;

  925.   if (ptid_equal (ptid, minus_one_ptid))
  926.     {
  927.       iterate_over_inferiors (gdbsim_stop_inferior, NULL);
  928.     }
  929.   else
  930.     {
  931.       struct inferior *inf = find_inferior_ptid (ptid);

  933.       if (inf == NULL)
  934.         error (_("Can't stop pid %d.  No inferior found."),
  935.                ptid_get_pid (ptid));

  937.       gdbsim_stop_inferior (inf, NULL);
  938.     }
  939. }

  941. /* GDB version of os_poll_quit callback.
  942.    Taken from gdb/util.c - should be in a library.  */

  944. static int
  945. ‌gdb_os_poll_quit (host_callback *p)
  946. {
  947.   if (deprecated_ui_loop_hook != NULL)
  948.     deprecated_ui_loop_hook (0);

  950.   if (check_quit_flag ())        /* gdb's idea of quit */
  951.     {
  952.       clear_quit_flag ();        /* we've stolen it */
  953.       return 1;
  954.     }
  955.   return 0;
  956. }

  958. /* Wait for inferior process to do something.  Return pid of child,
  959.    or -1 in case of error; store status through argument pointer STATUS,
  960.    just as `wait' would.  */

  962. static void
  963. ‌gdbsim_cntrl_c (int signo)
  964. {
  965.   gdbsim_stop (NULL, minus_one_ptid);
  966. }

  968. static ptid_t
  969. ‌gdbsim_wait (struct target_ops *ops,
  970.              ptid_t ptid, struct target_waitstatus *status, int options)
  971. {
  972.   struct sim_inferior_data *sim_data;
  973.   static RETSIGTYPE (*prev_sigint) ();
  974.   int sigrc = 0;
  975.   enum sim_stop reason = sim_running;

  977.   /* This target isn't able to (yet) resume more than one inferior at a time.
  978.      When ptid is minus_one_ptid, just use the current inferior.  If we're
  979.      given an explicit pid, we'll try to find it and use that instead.  */
  980.   if (ptid_equal (ptid, minus_one_ptid))
  981.     sim_data = get_sim_inferior_data (current_inferior (),
  982.                                       SIM_INSTANCE_NEEDED);
  983.   else
  984.     {
  985.       sim_data = get_sim_inferior_data_by_ptid (ptid, SIM_INSTANCE_NEEDED);
  986.       if (sim_data == NULL)
  987.         error (_("Unable to wait for pid %d.  Inferior not found."),
  988.                ptid_get_pid (ptid));
  989.       inferior_ptid = ptid;
  990.     }

  992.   if (remote_debug)
  993.     fprintf_unfiltered (gdb_stdlog, "gdbsim_wait\n");

  995. #if defined (HAVE_SIGACTION) && defined (SA_RESTART)
  996.   {
  997.     struct sigaction sa, osa;
  998.     sa.sa_handler = gdbsim_cntrl_c;
  999.     sigemptyset (&sa.sa_mask);
  1000.     sa.sa_flags = 0;
  1001.     sigaction (SIGINT, &sa, &osa);
  1002.     prev_sigint = osa.sa_handler;
  1003.   }
  1004. #else
  1005.   prev_sigint = signal (SIGINT, gdbsim_cntrl_c);
  1006. #endif
  1007.   sim_resume (sim_data->gdbsim_desc, sim_data->resume_step,
  1008.               sim_data->resume_siggnal);

  1010.   signal (SIGINT, prev_sigint);
  1011.   sim_data->resume_step = 0;

  1013.   sim_stop_reason (sim_data->gdbsim_desc, &reason, &sigrc);

  1015.   switch (reason)
  1016.     {
  1017.     case sim_exited:
  1018.       status->kind = TARGET_WAITKIND_EXITED;
  1019.       status->value.integer = sigrc;
  1020.       break;
  1021.     case sim_stopped:
  1022.       switch (sigrc)
  1023.         {
  1024.         case GDB_SIGNAL_ABRT:
  1025.           quit ();
  1026.           break;
  1027.         case GDB_SIGNAL_INT:
  1028.         case GDB_SIGNAL_TRAP:
  1029.         default:
  1030.           status->kind = TARGET_WAITKIND_STOPPED;
  1031.           status->value.sig = sigrc;
  1032.           break;
  1033.         }
  1034.       break;
  1035.     case sim_signalled:
  1036.       status->kind = TARGET_WAITKIND_SIGNALLED;
  1037.       status->value.sig = sigrc;
  1038.       break;
  1039.     case sim_running:
  1040.     case sim_polling:
  1041.       /* FIXME: Is this correct?  */
  1042.       break;
  1043.     }

  1045.   return inferior_ptid;
  1046. }

  1048. /* Get ready to modify the registers array.  On machines which store
  1049.    individual registers, this doesn't need to do anything.  On machines
  1050.    which store all the registers in one fell swoop, this makes sure
  1051.    that registers contains all the registers from the program being
  1052.    debugged.  */

  1054. static void
  1055. ‌gdbsim_prepare_to_store (struct target_ops *self, struct regcache *regcache)
  1056. {
  1057.   /* Do nothing, since we can store individual regs.  */
  1058. }

  1060. /* Helper for gdbsim_xfer_partial that handles memory transfers.
  1061.    Arguments are like target_xfer_partial.  */

  1063. static enum target_xfer_status
  1064. ‌gdbsim_xfer_memory (struct target_ops *target,
  1065.                     gdb_byte *readbuf, const gdb_byte *writebuf,
  1066.                     ULONGEST memaddr, ULONGEST len, ULONGEST *xfered_len)
  1067. {
  1068.   struct sim_inferior_data *sim_data
  1069.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);
  1070.   int l;

  1072.   /* If this target doesn't have memory yet, return 0 causing the
  1073.      request to be passed to a lower target, hopefully an exec
  1074.      file.  */
  1075.   if (!target->to_has_memory (target))
  1076.     return TARGET_XFER_EOF;

  1078.   if (!sim_data->program_loaded)
  1079.     error (_("No program loaded."));

  1081.   /* Note that we obtained the sim_data pointer above using
  1082.      SIM_INSTANCE_NOT_NEEDED.  We do this so that we don't needlessly
  1083.      allocate a sim instance prior to loading a program.   If we
  1084.      get to this point in the code though, gdbsim_desc should be
  1085.      non-NULL.  (Note that a sim instance is needed in order to load
  1086.      the program...)  */
  1087.   gdb_assert (sim_data->gdbsim_desc != NULL);

  1089.   if (remote_debug)
  1090.     fprintf_unfiltered (gdb_stdlog,
  1091.                         "gdbsim_xfer_memory: readbuf %s, writebuf %s, "
  1092.                         "memaddr %s, len %s\n",
  1093.                         host_address_to_string (readbuf),
  1094.                         host_address_to_string (writebuf),
  1095.                         paddress (target_gdbarch (), memaddr),
  1096.                         pulongest (len));

  1098.   if (writebuf)
  1099.     {
  1100.       if (remote_debug && len > 0)
  1101.         dump_mem (writebuf, len);
  1102.       l = sim_write (sim_data->gdbsim_desc, memaddr, writebuf, len);
  1103.     }
  1104.   else
  1105.     {
  1106.       l = sim_read (sim_data->gdbsim_desc, memaddr, readbuf, len);
  1107.       if (remote_debug && len > 0)
  1108.         dump_mem (readbuf, len);
  1109.     }
  1110.   if (l > 0)
  1111.     {
  1112.       *xfered_len = (ULONGEST) l;
  1113.       return TARGET_XFER_OK;
  1114.     }
  1115.   else if (l == 0)
  1116.     return TARGET_XFER_EOF;
  1117.   else
  1118.     return TARGET_XFER_E_IO;
  1119. }

  1121. /* Target to_xfer_partial implementation.  */

  1123. static enum target_xfer_status
  1124. ‌gdbsim_xfer_partial (struct target_ops *ops, enum target_object object,
  1125.                      const char *annex, gdb_byte *readbuf,
  1126.                      const gdb_byte *writebuf, ULONGEST offset, ULONGEST len,
  1127.                      ULONGEST *xfered_len)
  1128. {
  1129.   switch (object)
  1130.     {
  1131.     case TARGET_OBJECT_MEMORY:
  1132.       return gdbsim_xfer_memory (ops, readbuf, writebuf, offset, len,
  1133.                                  xfered_len);

  1135.     default:
  1136.       return TARGET_XFER_E_IO;
  1137.     }
  1138. }

  1140. static void
  1141. ‌gdbsim_files_info (struct target_ops *target)
  1142. {
  1143.   struct sim_inferior_data *sim_data
  1144.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);
  1145.   const char *file = "nothing";

  1147.   if (exec_bfd)
  1148.     file = bfd_get_filename (exec_bfd);

  1150.   if (remote_debug)
  1151.     fprintf_unfiltered (gdb_stdlog, "gdbsim_files_info: file \"%s\"\n", file);

  1153.   if (exec_bfd)
  1154.     {
  1155.       fprintf_unfiltered (gdb_stdlog, "\tAttached to %s running program %s\n",
  1156.                           target_shortname, file);
  1157.       sim_info (sim_data->gdbsim_desc, 0);
  1158.     }
  1159. }

  1161. /* Clear the simulator's notion of what the break points are.  */

  1163. static void
  1164. ‌gdbsim_mourn_inferior (struct target_ops *target)
  1165. {
  1166.   struct sim_inferior_data *sim_data
  1167.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);

  1169.   if (remote_debug)
  1170.     fprintf_unfiltered (gdb_stdlog, "gdbsim_mourn_inferior:\n");

  1172.   remove_breakpoints ();
  1173.   generic_mourn_inferior ();
  1174.   delete_thread_silent (sim_data->remote_sim_ptid);
  1175. }

  1177. /* Pass the command argument through to the simulator verbatim.  The
  1178.    simulator must do any command interpretation work.  */

  1180. void
  1181. ‌simulator_command (char *args, int from_tty)
  1182. {
  1183.   struct sim_inferior_data *sim_data;

  1185.   /* We use inferior_data() instead of get_sim_inferior_data() here in
  1186.      order to avoid attaching a sim_inferior_data struct to an
  1187.      inferior unnecessarily.  The reason we take such care here is due
  1188.      to the fact that this function, simulator_command(), may be called
  1189.      even when the sim target is not active.  If we were to use
  1190.      get_sim_inferior_data() here, it is possible that this call would
  1191.      be made either prior to gdbsim_open() or after gdbsim_close(),
  1192.      thus allocating memory that would not be garbage collected until
  1193.      the ultimate destruction of the associated inferior.  */

  1195.   sim_data  = inferior_data (current_inferior (), sim_inferior_data_key);
  1196.   if (sim_data == NULL || sim_data->gdbsim_desc == NULL)
  1197.     {

  1199.       /* PREVIOUSLY: The user may give a command before the simulator
  1200.          is opened. [...] (??? assuming of course one wishes to
  1201.          continue to allow commands to be sent to unopened simulators,
  1202.          which isn't entirely unreasonable).  */

  1204.       /* The simulator is a builtin abstraction of a remote target.
  1205.          Consistent with that model, access to the simulator, via sim
  1206.          commands, is restricted to the period when the channel to the
  1207.          simulator is open.  */

  1209.       error (_("Not connected to the simulator target"));
  1210.     }

  1212.   sim_do_command (sim_data->gdbsim_desc, args);

  1214.   /* Invalidate the register cache, in case the simulator command does
  1215.      something funny.  */
  1216.   registers_changed ();
  1217. }

  1219. ‌static VEC (char_ptr) *
  1220. sim_command_completer (struct cmd_list_element *ignore, const char *text,
  1221.                        const char *word)
  1222. {
  1223.   struct sim_inferior_data *sim_data;
  1224.   char **tmp;
  1225.   int i;
  1226.   VEC (char_ptr) *result = NULL;

  1228.   sim_data = inferior_data (current_inferior (), sim_inferior_data_key);
  1229.   if (sim_data == NULL || sim_data->gdbsim_desc == NULL)
  1230.     return NULL;

  1232.   tmp = sim_complete_command (sim_data->gdbsim_desc, text, word);
  1233.   if (tmp == NULL)
  1234.     return NULL;

  1236.   /* Transform the array into a VEC, and then free the array.  */
  1237.   for (i = 0; tmp[i] != NULL; i++)
  1238.     VEC_safe_push (char_ptr, result, tmp[i]);
  1239.   xfree (tmp);

  1241.   return result;
  1242. }

  1244. /* Check to see if a thread is still alive.  */

  1246. static int
  1247. ‌gdbsim_thread_alive (struct target_ops *ops, ptid_t ptid)
  1248. {
  1249.   struct sim_inferior_data *sim_data
  1250.     = get_sim_inferior_data_by_ptid (ptid, SIM_INSTANCE_NOT_NEEDED);

  1252.   if (sim_data == NULL)
  1253.     return 0;

  1255.   if (ptid_equal (ptid, sim_data->remote_sim_ptid))
  1256.     /* The simulators' task is always alive.  */
  1257.     return 1;

  1259.   return 0;
  1260. }

  1262. /* Convert a thread ID to a string.  Returns the string in a static
  1263.    buffer.  */

  1265. static char *
  1266. ‌gdbsim_pid_to_str (struct target_ops *ops, ptid_t ptid)
  1267. {
  1268.   return normal_pid_to_str (ptid);
  1269. }

  1271. /* Simulator memory may be accessed after the program has been loaded.  */

  1273. static int
  1274. ‌gdbsim_has_all_memory (struct target_ops *ops)
  1275. {
  1276.   struct sim_inferior_data *sim_data
  1277.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);

  1279.   if (!sim_data->program_loaded)
  1280.     return 0;

  1282.   return 1;
  1283. }

  1285. static int
  1286. ‌gdbsim_has_memory (struct target_ops *ops)
  1287. {
  1288.   struct sim_inferior_data *sim_data
  1289.     = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);

  1291.   if (!sim_data->program_loaded)
  1292.     return 0;

  1294.   return 1;
  1295. }

  1297. /* Define the target subroutine names.  */

  1299. ‌struct target_ops gdbsim_ops;

  1301. static void
  1302. ‌init_gdbsim_ops (void)
  1303. {
  1304.   gdbsim_ops.to_shortname = "sim";
  1305.   gdbsim_ops.to_longname = "simulator";
  1306.   gdbsim_ops.to_doc = "Use the compiled-in simulator.";
  1307.   gdbsim_ops.to_open = gdbsim_open;
  1308.   gdbsim_ops.to_close = gdbsim_close;
  1309.   gdbsim_ops.to_detach = gdbsim_detach;
  1310.   gdbsim_ops.to_resume = gdbsim_resume;
  1311.   gdbsim_ops.to_wait = gdbsim_wait;
  1312.   gdbsim_ops.to_fetch_registers = gdbsim_fetch_register;
  1313.   gdbsim_ops.to_store_registers = gdbsim_store_register;
  1314.   gdbsim_ops.to_prepare_to_store = gdbsim_prepare_to_store;
  1315.   gdbsim_ops.to_xfer_partial = gdbsim_xfer_partial;
  1316.   gdbsim_ops.to_files_info = gdbsim_files_info;
  1317.   gdbsim_ops.to_insert_breakpoint = memory_insert_breakpoint;
  1318.   gdbsim_ops.to_remove_breakpoint = memory_remove_breakpoint;
  1319.   gdbsim_ops.to_kill = gdbsim_kill;
  1320.   gdbsim_ops.to_load = gdbsim_load;
  1321.   gdbsim_ops.to_create_inferior = gdbsim_create_inferior;
  1322.   gdbsim_ops.to_mourn_inferior = gdbsim_mourn_inferior;
  1323.   gdbsim_ops.to_stop = gdbsim_stop;
  1324.   gdbsim_ops.to_thread_alive = gdbsim_thread_alive;
  1325.   gdbsim_ops.to_pid_to_str = gdbsim_pid_to_str;
  1326.   gdbsim_ops.to_stratum = process_stratum;
  1327.   gdbsim_ops.to_has_all_memory = gdbsim_has_all_memory;
  1328.   gdbsim_ops.to_has_memory = gdbsim_has_memory;
  1329.   gdbsim_ops.to_has_stack = default_child_has_stack;
  1330.   gdbsim_ops.to_has_registers = default_child_has_registers;
  1331.   gdbsim_ops.to_has_execution = default_child_has_execution;
  1332.   gdbsim_ops.to_magic = OPS_MAGIC;
  1333. }

  1335. void
  1336. ‌_initialize_remote_sim (void)
  1337. {
  1338.   struct cmd_list_element *c;

  1340.   init_gdbsim_ops ();
  1341.   add_target (&gdbsim_ops);

  1343.   c = add_com ("sim", class_obscure, simulator_command,
  1344.                _("Send a command to the simulator."));
  1345.   set_cmd_completer (c, sim_command_completer);

  1347.   sim_inferior_data_key
  1348.     = register_inferior_data_with_cleanup (NULL, sim_inferior_data_cleanup);
  1349. }