Fix null pointer dereference in process_debug_info()
[binutils-gdb.git] / gdb / remote-sim.c
blob5fccefe93a161f1cd4d0c706c685ff6baa304a98
1 /* Generic remote debugging interface for simulators.
3 Copyright (C) 1993-2024 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 "gdb_bfd.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 "process-stratum-target.h"
34 #include "gdbcore.h"
35 #include "sim/callback.h"
36 #include "sim/sim.h"
37 #include "command.h"
38 #include "regcache.h"
39 #include "sim-regno.h"
40 #include "arch-utils.h"
41 #include "readline/readline.h"
42 #include "gdbthread.h"
43 #include "gdbsupport/byte-vector.h"
44 #include "memory-map.h"
45 #include "remote.h"
46 #include "gdbsupport/buildargv.h"
48 /* Prototypes */
50 static void init_callbacks (void);
52 static void end_callbacks (void);
54 static int gdb_os_write_stdout (host_callback *, const char *, int);
56 static void gdb_os_flush_stdout (host_callback *);
58 static int gdb_os_write_stderr (host_callback *, const char *, int);
60 static void gdb_os_flush_stderr (host_callback *);
62 static int gdb_os_poll_quit (host_callback *);
64 /* gdb_printf is depreciated. */
65 static void gdb_os_printf_filtered (host_callback *, const char *, ...);
67 static void gdb_os_vprintf_filtered (host_callback *, const char *, va_list);
69 static void gdb_os_evprintf_filtered (host_callback *, const char *, va_list);
71 static void gdb_os_error (host_callback *, const char *, ...)
72 ATTRIBUTE_NORETURN;
74 /* Naming convention:
76 sim_* are the interface to the simulator (see remote-sim.h).
77 gdbsim_* are stuff which is internal to gdb. */
79 /* Value of the next pid to allocate for an inferior. As indicated
80 elsewhere, its initial value is somewhat arbitrary; it's critical
81 though that it's not zero or negative. */
82 static int next_pid;
83 #define INITIAL_PID 42000
85 /* Simulator-specific, per-inferior state. */
86 struct sim_inferior_data {
87 explicit sim_inferior_data (SIM_DESC desc)
88 : gdbsim_desc (desc),
89 remote_sim_ptid (next_pid, 0, next_pid)
91 gdb_assert (remote_sim_ptid != null_ptid);
92 ++next_pid;
95 ~sim_inferior_data ();
97 /* Flag which indicates whether or not the program has been loaded. */
98 bool program_loaded = false;
100 /* Simulator descriptor for this inferior. */
101 SIM_DESC gdbsim_desc;
103 /* This is the ptid we use for this particular simulator instance. Its
104 value is somewhat arbitrary, as the simulator target don't have a
105 notion of tasks or threads, but we need something non-null to place
106 in inferior_ptid. For simulators which permit multiple instances,
107 we also need a unique identifier to use for each inferior. */
108 ptid_t remote_sim_ptid;
110 /* Signal with which to resume. */
111 enum gdb_signal resume_siggnal = GDB_SIGNAL_0;
113 /* Flag which indicates whether resume should step or not. */
114 bool resume_step = false;
117 static const target_info gdbsim_target_info = {
118 "sim",
119 N_("simulator"),
120 N_("Use the compiled-in simulator.")
123 struct gdbsim_target final
124 : public memory_breakpoint_target<process_stratum_target>
126 gdbsim_target () = default;
128 const target_info &info () const override
129 { return gdbsim_target_info; }
131 void close () override;
133 void detach (inferior *inf, int) override;
135 void resume (ptid_t, int, enum gdb_signal) override;
136 ptid_t wait (ptid_t, struct target_waitstatus *, target_wait_flags) override;
138 void fetch_registers (struct regcache *, int) override;
139 void store_registers (struct regcache *, int) override;
140 void prepare_to_store (struct regcache *) override;
142 enum target_xfer_status xfer_partial (enum target_object object,
143 const char *annex,
144 gdb_byte *readbuf,
145 const gdb_byte *writebuf,
146 ULONGEST offset, ULONGEST len,
147 ULONGEST *xfered_len) override;
149 void files_info () override;
151 void kill () override;
153 void load (const char *, int) override;
155 bool can_create_inferior () override { return true; }
156 void create_inferior (const char *, const std::string &,
157 char **, int) override;
159 void mourn_inferior () override;
161 void interrupt () override;
163 bool thread_alive (ptid_t ptid) override;
165 std::string pid_to_str (ptid_t) override;
167 bool has_all_memory () override;
168 bool has_memory () override;
169 std::vector<mem_region> memory_map () override;
171 private:
172 sim_inferior_data *get_inferior_data_by_ptid (ptid_t ptid,
173 int sim_instance_needed);
174 void resume_one_inferior (inferior *inf, bool step, gdb_signal siggnal);
175 void close_one_inferior (inferior *inf);
178 static struct gdbsim_target gdbsim_ops;
180 static const registry<inferior>::key<sim_inferior_data> sim_inferior_data_key;
182 /* Flag indicating the "open" status of this module. It's set true
183 in gdbsim_open() and false in gdbsim_close(). */
184 static bool gdbsim_is_open = false;
186 /* Argument list to pass to sim_open(). It is allocated in gdbsim_open()
187 and deallocated in gdbsim_close(). The lifetime needs to extend beyond
188 the call to gdbsim_open() due to the fact that other sim instances other
189 than the first will be allocated after the gdbsim_open() call. */
190 static char **sim_argv = NULL;
192 /* OS-level callback functions for write, flush, etc. */
193 static host_callback gdb_callback;
194 static int callbacks_initialized = 0;
196 /* Flags indicating whether or not a sim instance is needed. One of these
197 flags should be passed to get_sim_inferior_data(). */
199 enum {SIM_INSTANCE_NOT_NEEDED = 0, SIM_INSTANCE_NEEDED = 1};
201 /* Obtain pointer to per-inferior simulator data, allocating it if necessary.
202 Attempt to open the sim if SIM_INSTANCE_NEEDED is true. */
204 static struct sim_inferior_data *
205 get_sim_inferior_data (struct inferior *inf, int sim_instance_needed)
207 SIM_DESC sim_desc = NULL;
208 struct sim_inferior_data *sim_data = sim_inferior_data_key.get (inf);
210 /* Try to allocate a new sim instance, if needed. We do this ahead of
211 a potential allocation of a sim_inferior_data struct in order to
212 avoid needlessly allocating that struct in the event that the sim
213 instance allocation fails. */
214 if (sim_instance_needed == SIM_INSTANCE_NEEDED
215 && (sim_data == NULL || sim_data->gdbsim_desc == NULL))
217 sim_desc = sim_open (SIM_OPEN_DEBUG, &gdb_callback,
218 current_program_space->exec_bfd (), sim_argv);
219 if (sim_desc == NULL)
220 error (_("Unable to create simulator instance for inferior %d."),
221 inf->num);
223 /* Check if the sim descriptor is the same as that of another
224 inferior. */
225 for (inferior *other_inf : all_inferiors ())
227 sim_inferior_data *other_sim_data
228 = sim_inferior_data_key.get (other_inf);
230 if (other_sim_data != NULL
231 && other_sim_data->gdbsim_desc == sim_desc)
233 /* We don't close the descriptor due to the fact that it's
234 shared with some other inferior. If we were to close it,
235 that might needlessly muck up the other inferior. Of
236 course, it's possible that the damage has already been
237 done... Note that it *will* ultimately be closed during
238 cleanup of the other inferior. */
239 sim_desc = NULL;
240 error (
241 _("Inferior %d and inferior %d would have identical simulator state.\n"
242 "(This simulator does not support the running of more than one inferior.)"),
243 inf->num, other_inf->num);
248 if (sim_data == NULL)
250 sim_data = sim_inferior_data_key.emplace (inf, sim_desc);
252 else if (sim_desc)
254 /* This handles the case where sim_data was allocated prior to
255 needing a sim instance. */
256 sim_data->gdbsim_desc = sim_desc;
260 return sim_data;
263 /* Return pointer to per-inferior simulator data using PTID to find the
264 inferior in question. Return NULL when no inferior is found or
265 when ptid has a zero or negative pid component. */
267 sim_inferior_data *
268 gdbsim_target::get_inferior_data_by_ptid (ptid_t ptid,
269 int sim_instance_needed)
271 struct inferior *inf;
272 int pid = ptid.pid ();
274 if (pid <= 0)
275 return NULL;
277 inf = find_inferior_pid (this, pid);
279 if (inf)
280 return get_sim_inferior_data (inf, sim_instance_needed);
281 else
282 return NULL;
285 /* Free the per-inferior simulator data. */
287 sim_inferior_data::~sim_inferior_data ()
289 if (gdbsim_desc)
290 sim_close (gdbsim_desc, 0);
293 static void
294 dump_mem (const gdb_byte *buf, int len)
296 gdb_puts ("\t", gdb_stdlog);
298 if (len == 8 || len == 4)
300 uint32_t l[2];
302 memcpy (l, buf, len);
303 gdb_printf (gdb_stdlog, "0x%08x", l[0]);
304 if (len == 8)
305 gdb_printf (gdb_stdlog, " 0x%08x", l[1]);
307 else
309 int i;
311 for (i = 0; i < len; i++)
312 gdb_printf (gdb_stdlog, "0x%02x ", buf[i]);
315 gdb_puts ("\n", gdb_stdlog);
318 /* Initialize gdb_callback. */
320 static void
321 init_callbacks (void)
323 if (!callbacks_initialized)
325 gdb_callback = default_callback;
326 gdb_callback.init (&gdb_callback);
327 gdb_callback.write_stdout = gdb_os_write_stdout;
328 gdb_callback.flush_stdout = gdb_os_flush_stdout;
329 gdb_callback.write_stderr = gdb_os_write_stderr;
330 gdb_callback.flush_stderr = gdb_os_flush_stderr;
331 gdb_callback.printf_filtered = gdb_os_printf_filtered;
332 gdb_callback.vprintf_filtered = gdb_os_vprintf_filtered;
333 gdb_callback.evprintf_filtered = gdb_os_evprintf_filtered;
334 gdb_callback.error = gdb_os_error;
335 gdb_callback.poll_quit = gdb_os_poll_quit;
336 gdb_callback.magic = HOST_CALLBACK_MAGIC;
337 callbacks_initialized = 1;
341 /* Release callbacks (free resources used by them). */
343 static void
344 end_callbacks (void)
346 if (callbacks_initialized)
348 gdb_callback.shutdown (&gdb_callback);
349 callbacks_initialized = 0;
353 /* GDB version of os_write_stdout callback. */
355 static int
356 gdb_os_write_stdout (host_callback *p, const char *buf, int len)
358 gdb_stdtarg->write (buf, len);
359 return len;
362 /* GDB version of os_flush_stdout callback. */
364 static void
365 gdb_os_flush_stdout (host_callback *p)
367 gdb_stdtarg->flush ();
370 /* GDB version of os_write_stderr callback. */
372 static int
373 gdb_os_write_stderr (host_callback *p, const char *buf, int len)
375 int i;
376 char b[2];
378 for (i = 0; i < len; i++)
380 b[0] = buf[i];
381 b[1] = 0;
382 gdb_stdtargerr->puts (b);
384 return len;
387 /* GDB version of os_flush_stderr callback. */
389 static void
390 gdb_os_flush_stderr (host_callback *p)
392 gdb_stdtargerr->flush ();
395 /* GDB version of gdb_printf callback. */
397 static void ATTRIBUTE_PRINTF (2, 3)
398 gdb_os_printf_filtered (host_callback * p, const char *format, ...)
400 va_list args;
402 va_start (args, format);
403 gdb_vprintf (gdb_stdout, format, args);
404 va_end (args);
407 /* GDB version of error gdb_vprintf. */
409 static void ATTRIBUTE_PRINTF (2, 0)
410 gdb_os_vprintf_filtered (host_callback * p, const char *format, va_list ap)
412 gdb_vprintf (gdb_stdout, format, ap);
415 /* GDB version of error evprintf_filtered. */
417 static void ATTRIBUTE_PRINTF (2, 0)
418 gdb_os_evprintf_filtered (host_callback * p, const char *format, va_list ap)
420 gdb_vprintf (gdb_stderr, format, ap);
423 /* GDB version of error callback. */
425 static void ATTRIBUTE_PRINTF (2, 3)
426 gdb_os_error (host_callback * p, const char *format, ...)
428 va_list args;
430 va_start (args, format);
431 verror (format, args);
432 va_end (args);
436 one2one_register_sim_regno (struct gdbarch *gdbarch, int regnum)
438 /* Only makes sense to supply raw registers. */
439 gdb_assert (regnum >= 0 && regnum < gdbarch_num_regs (gdbarch));
440 return regnum;
443 void
444 gdbsim_target::fetch_registers (struct regcache *regcache, int regno)
446 struct gdbarch *gdbarch = regcache->arch ();
447 struct inferior *inf = find_inferior_ptid (this, regcache->ptid ());
448 struct sim_inferior_data *sim_data
449 = get_sim_inferior_data (inf, SIM_INSTANCE_NEEDED);
451 if (regno == -1)
453 for (regno = 0; regno < gdbarch_num_regs (gdbarch); regno++)
454 fetch_registers (regcache, regno);
455 return;
458 switch (gdbarch_register_sim_regno (gdbarch, regno))
460 case LEGACY_SIM_REGNO_IGNORE:
461 break;
462 case SIM_REGNO_DOES_NOT_EXIST:
464 /* For moment treat a `does not exist' register the same way
465 as an ``unavailable'' register. */
466 regcache->raw_supply_zeroed (regno);
467 break;
470 default:
472 static int warn_user = 1;
473 int regsize = register_size (gdbarch, regno);
474 gdb::byte_vector buf (regsize, 0);
475 int nr_bytes;
477 gdb_assert (regno >= 0 && regno < gdbarch_num_regs (gdbarch));
478 nr_bytes = sim_fetch_register (sim_data->gdbsim_desc,
479 gdbarch_register_sim_regno
480 (gdbarch, regno),
481 buf.data (), regsize);
482 if (nr_bytes > 0 && nr_bytes != regsize && warn_user)
484 gdb_printf (gdb_stderr,
485 "Size of register %s (%d/%d) "
486 "incorrect (%d instead of %d))",
487 gdbarch_register_name (gdbarch, regno),
488 regno,
489 gdbarch_register_sim_regno (gdbarch, regno),
490 nr_bytes, regsize);
491 warn_user = 0;
493 /* FIXME: cagney/2002-05-27: Should check `nr_bytes == 0'
494 indicating that GDB and the SIM have different ideas about
495 which registers are fetchable. */
496 /* Else if (nr_bytes < 0): an old simulator, that doesn't
497 think to return the register size. Just assume all is ok. */
498 regcache->raw_supply (regno, buf.data ());
499 if (remote_debug)
501 gdb_printf (gdb_stdlog,
502 "gdbsim_fetch_register: %d", regno);
503 /* FIXME: We could print something more intelligible. */
504 dump_mem (buf.data (), regsize);
506 break;
512 void
513 gdbsim_target::store_registers (struct regcache *regcache, int regno)
515 struct gdbarch *gdbarch = regcache->arch ();
516 struct inferior *inf = find_inferior_ptid (this, regcache->ptid ());
517 struct sim_inferior_data *sim_data
518 = get_sim_inferior_data (inf, SIM_INSTANCE_NEEDED);
520 if (regno == -1)
522 for (regno = 0; regno < gdbarch_num_regs (gdbarch); regno++)
523 store_registers (regcache, regno);
524 return;
526 else if (gdbarch_register_sim_regno (gdbarch, regno) >= 0)
528 int regsize = register_size (gdbarch, regno);
529 gdb::byte_vector tmp (regsize);
530 int nr_bytes;
532 regcache->cooked_read (regno, tmp.data ());
533 nr_bytes = sim_store_register (sim_data->gdbsim_desc,
534 gdbarch_register_sim_regno
535 (gdbarch, regno),
536 tmp.data (), regsize);
538 if (nr_bytes > 0 && nr_bytes != regsize)
539 internal_error (_("Register size different to expected"));
540 if (nr_bytes < 0)
541 internal_error (_("Register %d not updated"), regno);
542 if (nr_bytes == 0)
543 warning (_("Register %s not updated"),
544 gdbarch_register_name (gdbarch, regno));
546 if (remote_debug)
548 gdb_printf (gdb_stdlog, "gdbsim_store_register: %d", regno);
549 /* FIXME: We could print something more intelligible. */
550 dump_mem (tmp.data (), regsize);
555 /* Kill the running program. This may involve closing any open files
556 and releasing other resources acquired by the simulated program. */
558 void
559 gdbsim_target::kill ()
561 if (remote_debug)
562 gdb_printf (gdb_stdlog, "gdbsim_kill\n");
564 /* There is no need to `kill' running simulator - the simulator is
565 not running. Mourning it is enough. */
566 target_mourn_inferior (inferior_ptid);
569 /* Load an executable file into the target process. This is expected to
570 not only bring new code into the target process, but also to update
571 GDB's symbol tables to match. */
573 void
574 gdbsim_target::load (const char *args, int fromtty)
576 const char *prog;
577 struct sim_inferior_data *sim_data
578 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);
580 if (args == NULL)
581 error_no_arg (_("program to load"));
583 gdb_argv argv (args);
585 prog = tilde_expand (argv[0]);
587 if (argv[1] != NULL)
588 error (_("GDB sim does not yet support a load offset."));
590 if (remote_debug)
591 gdb_printf (gdb_stdlog, "gdbsim_load: prog \"%s\"\n", prog);
593 /* FIXME: We will print two messages on error.
594 Need error to either not print anything if passed NULL or need
595 another routine that doesn't take any arguments. */
596 if (sim_load (sim_data->gdbsim_desc, prog, NULL, fromtty) == SIM_RC_FAIL)
597 error (_("unable to load program"));
599 /* FIXME: If a load command should reset the targets registers then
600 a call to sim_create_inferior() should go here. */
602 sim_data->program_loaded = true;
606 /* Start an inferior process and set inferior_ptid to its pid.
607 EXEC_FILE is the file to run.
608 ARGS is a string containing the arguments to the program.
609 ENV is the environment vector to pass. Errors reported with error().
610 On VxWorks and various standalone systems, we ignore exec_file. */
611 /* This is called not only when we first attach, but also when the
612 user types "run" after having attached. */
614 void
615 gdbsim_target::create_inferior (const char *exec_file,
616 const std::string &allargs,
617 char **env, int from_tty)
619 struct sim_inferior_data *sim_data
620 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);
621 int len;
622 char *arg_buf;
623 const char *args = allargs.c_str ();
625 if (exec_file == 0 || current_program_space->exec_bfd () == 0)
626 warning (_("No executable file specified."));
627 if (!sim_data->program_loaded)
628 warning (_("No program loaded."));
630 if (remote_debug)
631 gdb_printf (gdb_stdlog,
632 "gdbsim_create_inferior: exec_file \"%s\", args \"%s\"\n",
633 (exec_file ? exec_file : "(NULL)"),
634 args);
636 if (inferior_ptid == sim_data->remote_sim_ptid)
637 kill ();
638 remove_breakpoints ();
639 init_wait_for_inferior ();
641 gdb_argv built_argv;
642 if (exec_file != NULL)
644 len = strlen (exec_file) + 1 + allargs.size () + 1 + /*slop */ 10;
645 arg_buf = (char *) alloca (len);
646 arg_buf[0] = '\0';
647 strcat (arg_buf, exec_file);
648 strcat (arg_buf, " ");
649 strcat (arg_buf, args);
650 built_argv.reset (arg_buf);
653 if (sim_create_inferior (sim_data->gdbsim_desc,
654 current_program_space->exec_bfd (),
655 built_argv.get (), env)
656 != SIM_RC_OK)
657 error (_("Unable to create sim inferior."));
659 inferior_appeared (current_inferior (),
660 sim_data->remote_sim_ptid.pid ());
661 thread_info *thr = add_thread_silent (this, sim_data->remote_sim_ptid);
662 switch_to_thread (thr);
664 insert_breakpoints (); /* Needed to get correct instruction
665 in cache. */
667 clear_proceed_status (0);
670 /* The open routine takes the rest of the parameters from the command,
671 and (if successful) pushes a new target onto the stack.
672 Targets should supply this routine, if only to provide an error message. */
673 /* Called when selecting the simulator. E.g. (gdb) target sim name. */
675 static void
676 gdbsim_target_open (const char *args, int from_tty)
678 int len;
679 char *arg_buf;
680 struct sim_inferior_data *sim_data;
681 SIM_DESC gdbsim_desc;
683 const char *sysroot = gdb_sysroot.c_str ();
684 if (is_target_filename (sysroot))
685 sysroot += strlen (TARGET_SYSROOT_PREFIX);
687 if (remote_debug)
688 gdb_printf (gdb_stdlog,
689 "gdbsim_open: args \"%s\"\n", args ? args : "(null)");
691 /* Ensure that the sim target is not on the target stack. This is
692 necessary, because if it is on the target stack, the call to
693 push_target below will invoke sim_close(), thus freeing various
694 state (including a sim instance) that we allocate prior to
695 invoking push_target(). We want to delay the push_target()
696 operation until after we complete those operations which could
697 error out. */
698 if (gdbsim_is_open)
699 current_inferior ()->unpush_target (&gdbsim_ops);
701 len = (7 + 1 /* gdbsim */
702 + strlen (" -E little")
703 + strlen (" --architecture=xxxxxxxxxx")
704 + strlen (" --sysroot=") + strlen (sysroot) +
705 + (args ? strlen (args) : 0)
706 + 50) /* slack */ ;
707 arg_buf = (char *) alloca (len);
708 strcpy (arg_buf, "gdbsim"); /* 7 */
709 /* Specify the byte order for the target when it is explicitly
710 specified by the user (not auto detected). */
711 switch (selected_byte_order ())
713 case BFD_ENDIAN_BIG:
714 strcat (arg_buf, " -E big");
715 break;
716 case BFD_ENDIAN_LITTLE:
717 strcat (arg_buf, " -E little");
718 break;
719 case BFD_ENDIAN_UNKNOWN:
720 break;
722 /* Specify the architecture of the target when it has been
723 explicitly specified */
724 if (selected_architecture_name () != NULL)
726 strcat (arg_buf, " --architecture=");
727 strcat (arg_buf, selected_architecture_name ());
729 /* Pass along gdb's concept of the sysroot. */
730 strcat (arg_buf, " --sysroot=");
731 strcat (arg_buf, sysroot);
732 /* finally, any explicit args */
733 if (args)
735 strcat (arg_buf, " "); /* 1 */
736 strcat (arg_buf, args);
739 gdb_argv argv (arg_buf);
740 sim_argv = argv.release ();
742 init_callbacks ();
743 gdbsim_desc = sim_open (SIM_OPEN_DEBUG, &gdb_callback,
744 current_program_space->exec_bfd (), sim_argv);
746 if (gdbsim_desc == 0)
748 freeargv (sim_argv);
749 sim_argv = NULL;
750 error (_("unable to create simulator instance"));
753 /* Reset the pid numberings for this batch of sim instances. */
754 next_pid = INITIAL_PID;
756 /* Allocate the inferior data, but do not allocate a sim instance
757 since we've already just done that. */
758 sim_data = get_sim_inferior_data (current_inferior (),
759 SIM_INSTANCE_NOT_NEEDED);
761 sim_data->gdbsim_desc = gdbsim_desc;
763 current_inferior ()->push_target (&gdbsim_ops);
764 gdb_printf ("Connected to the simulator.\n");
766 /* There's nothing running after "target sim" or "load"; not until
767 "run". */
768 switch_to_no_thread ();
770 gdbsim_is_open = true;
773 /* Helper for gdbsim_target::close. */
775 void
776 gdbsim_target::close_one_inferior (inferior *inf)
778 struct sim_inferior_data *sim_data = sim_inferior_data_key.get (inf);
779 if (sim_data != NULL)
781 ptid_t ptid = sim_data->remote_sim_ptid;
783 sim_inferior_data_key.clear (inf);
785 /* Having a ptid allocated and stored in remote_sim_ptid does
786 not mean that a corresponding inferior was ever created.
787 Thus we need to verify the existence of an inferior using the
788 pid in question before setting inferior_ptid via
789 switch_to_thread() or mourning the inferior. */
790 if (find_inferior_ptid (this, ptid) != NULL)
792 switch_to_thread (this, ptid);
793 generic_mourn_inferior ();
798 /* Close out all files and local state before this target loses control. */
800 void
801 gdbsim_target::close ()
803 if (remote_debug)
804 gdb_printf (gdb_stdlog, "gdbsim_close\n");
806 for (inferior *inf : all_inferiors (this))
807 close_one_inferior (inf);
809 if (sim_argv != NULL)
811 freeargv (sim_argv);
812 sim_argv = NULL;
815 end_callbacks ();
817 gdbsim_is_open = false;
820 /* Takes a program previously attached to and detaches it.
821 The program may resume execution (some targets do, some don't) and will
822 no longer stop on signals, etc. We better not have left any breakpoints
823 in the program or it'll die when it hits one. FROM_TTY says whether to be
824 verbose or not. */
825 /* Terminate the open connection to the remote debugger.
826 Use this when you want to detach and do something else with your gdb. */
828 void
829 gdbsim_target::detach (inferior *inf, int from_tty)
831 if (remote_debug)
832 gdb_printf (gdb_stdlog, "gdbsim_detach\n");
834 inf->unpush_target (this); /* calls gdbsim_close to do the real work */
835 if (from_tty)
836 gdb_printf ("Ending simulator %s debugging\n", target_shortname ());
839 /* Resume execution of the target process. STEP says whether to single-step
840 or to run free; SIGGNAL is the signal value (e.g. SIGINT) to be given
841 to the target, or zero for no signal. */
843 void
844 gdbsim_target::resume_one_inferior (inferior *inf, bool step,
845 gdb_signal siggnal)
847 struct sim_inferior_data *sim_data
848 = get_sim_inferior_data (inf, SIM_INSTANCE_NOT_NEEDED);
850 if (sim_data)
852 sim_data->resume_siggnal = siggnal;
853 sim_data->resume_step = step;
855 if (remote_debug)
856 gdb_printf (gdb_stdlog,
857 _("gdbsim_resume: pid %d, step %d, signal %d\n"),
858 inf->pid, step, siggnal);
862 void
863 gdbsim_target::resume (ptid_t ptid, int step, enum gdb_signal siggnal)
865 struct sim_inferior_data *sim_data
866 = get_inferior_data_by_ptid (ptid, SIM_INSTANCE_NOT_NEEDED);
868 /* We don't access any sim_data members within this function.
869 What's of interest is whether or not the call to
870 get_sim_inferior_data_by_ptid(), above, is able to obtain a
871 non-NULL pointer. If it managed to obtain a non-NULL pointer, we
872 know we have a single inferior to consider. If it's NULL, we
873 either have multiple inferiors to resume or an error condition. */
875 if (sim_data)
876 resume_one_inferior (find_inferior_ptid (this, ptid), step, siggnal);
877 else if (ptid == minus_one_ptid)
879 for (inferior *inf : all_inferiors (this))
880 resume_one_inferior (inf, step, siggnal);
882 else
883 error (_("The program is not being run."));
886 /* Notify the simulator of an asynchronous request to interrupt.
888 The simulator shall ensure that the interrupt request is eventually
889 delivered to the simulator. If the call is made while the
890 simulator is not running then the interrupt request is processed when
891 the simulator is next resumed.
893 For simulators that do not support this operation, just abort. */
895 void
896 gdbsim_target::interrupt ()
898 for (inferior *inf : all_inferiors ())
900 sim_inferior_data *sim_data
901 = get_sim_inferior_data (inf, SIM_INSTANCE_NEEDED);
903 if (sim_data != nullptr && !sim_stop (sim_data->gdbsim_desc))
904 quit ();
908 /* GDB version of os_poll_quit callback.
909 Taken from gdb/util.c - should be in a library. */
911 static int
912 gdb_os_poll_quit (host_callback *p)
914 if (deprecated_ui_loop_hook != NULL)
915 deprecated_ui_loop_hook (0);
917 if (check_quit_flag ()) /* gdb's idea of quit */
918 return 1;
919 return 0;
922 /* Wait for inferior process to do something. Return pid of child,
923 or -1 in case of error; store status through argument pointer STATUS,
924 just as `wait' would. */
926 static void
927 gdbsim_cntrl_c (int signo)
929 gdbsim_ops.interrupt ();
932 ptid_t
933 gdbsim_target::wait (ptid_t ptid, struct target_waitstatus *status,
934 target_wait_flags options)
936 struct sim_inferior_data *sim_data;
937 static sighandler_t prev_sigint;
938 int sigrc = 0;
939 enum sim_stop reason = sim_running;
941 /* This target isn't able to (yet) resume more than one inferior at a time.
942 When ptid is minus_one_ptid, just use the current inferior. If we're
943 given an explicit pid, we'll try to find it and use that instead. */
944 if (ptid == minus_one_ptid)
945 sim_data = get_sim_inferior_data (current_inferior (),
946 SIM_INSTANCE_NEEDED);
947 else
949 sim_data = get_inferior_data_by_ptid (ptid, SIM_INSTANCE_NEEDED);
950 if (sim_data == NULL)
951 error (_("Unable to wait for pid %d. Inferior not found."),
952 ptid.pid ());
955 if (remote_debug)
956 gdb_printf (gdb_stdlog, "gdbsim_wait\n");
958 #if defined (HAVE_SIGACTION) && defined (SA_RESTART)
960 struct sigaction sa, osa;
961 sa.sa_handler = gdbsim_cntrl_c;
962 sigemptyset (&sa.sa_mask);
963 sa.sa_flags = 0;
964 sigaction (SIGINT, &sa, &osa);
965 prev_sigint = osa.sa_handler;
967 #else
968 prev_sigint = signal (SIGINT, gdbsim_cntrl_c);
969 #endif
970 sim_resume (sim_data->gdbsim_desc, sim_data->resume_step ? 1 : 0,
971 sim_data->resume_siggnal);
973 signal (SIGINT, prev_sigint);
974 sim_data->resume_step = false;
976 sim_stop_reason (sim_data->gdbsim_desc, &reason, &sigrc);
978 switch (reason)
980 case sim_exited:
981 status->set_exited (sigrc);
982 break;
983 case sim_stopped:
984 switch (sigrc)
986 case GDB_SIGNAL_ABRT:
987 quit ();
988 break;
989 case GDB_SIGNAL_INT:
990 case GDB_SIGNAL_TRAP:
991 default:
992 status->set_stopped ((gdb_signal) sigrc);
993 break;
995 break;
996 case sim_signalled:
997 status->set_signalled ((gdb_signal) sigrc);
998 break;
999 case sim_running:
1000 case sim_polling:
1001 /* FIXME: Is this correct? */
1002 break;
1005 return sim_data->remote_sim_ptid;
1008 /* Get ready to modify the registers array. On machines which store
1009 individual registers, this doesn't need to do anything. On machines
1010 which store all the registers in one fell swoop, this makes sure
1011 that registers contains all the registers from the program being
1012 debugged. */
1014 void
1015 gdbsim_target::prepare_to_store (struct regcache *regcache)
1017 /* Do nothing, since we can store individual regs. */
1020 /* Helper for gdbsim_xfer_partial that handles memory transfers.
1021 Arguments are like target_xfer_partial. */
1023 static enum target_xfer_status
1024 gdbsim_xfer_memory (struct target_ops *target,
1025 gdb_byte *readbuf, const gdb_byte *writebuf,
1026 ULONGEST memaddr, ULONGEST len, ULONGEST *xfered_len)
1028 struct sim_inferior_data *sim_data
1029 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);
1030 int l;
1032 /* If this target doesn't have memory yet, return 0 causing the
1033 request to be passed to a lower target, hopefully an exec
1034 file. */
1035 if (!target->has_memory ())
1036 return TARGET_XFER_EOF;
1038 if (!sim_data->program_loaded)
1039 error (_("No program loaded."));
1041 /* Note that we obtained the sim_data pointer above using
1042 SIM_INSTANCE_NOT_NEEDED. We do this so that we don't needlessly
1043 allocate a sim instance prior to loading a program. If we
1044 get to this point in the code though, gdbsim_desc should be
1045 non-NULL. (Note that a sim instance is needed in order to load
1046 the program...) */
1047 gdb_assert (sim_data->gdbsim_desc != NULL);
1049 if (remote_debug)
1050 gdb_printf (gdb_stdlog,
1051 "gdbsim_xfer_memory: readbuf %s, writebuf %s, "
1052 "memaddr %s, len %s\n",
1053 host_address_to_string (readbuf),
1054 host_address_to_string (writebuf),
1055 paddress (current_inferior ()->arch (), memaddr),
1056 pulongest (len));
1058 if (writebuf)
1060 if (remote_debug && len > 0)
1061 dump_mem (writebuf, len);
1062 l = sim_write (sim_data->gdbsim_desc, memaddr, writebuf, len);
1064 else
1066 l = sim_read (sim_data->gdbsim_desc, memaddr, readbuf, len);
1067 if (remote_debug && len > 0)
1068 dump_mem (readbuf, len);
1070 if (l > 0)
1072 *xfered_len = (ULONGEST) l;
1073 return TARGET_XFER_OK;
1075 else if (l == 0)
1076 return TARGET_XFER_EOF;
1077 else
1078 return TARGET_XFER_E_IO;
1081 /* Target to_xfer_partial implementation. */
1083 enum target_xfer_status
1084 gdbsim_target::xfer_partial (enum target_object object,
1085 const char *annex, gdb_byte *readbuf,
1086 const gdb_byte *writebuf, ULONGEST offset, ULONGEST len,
1087 ULONGEST *xfered_len)
1089 switch (object)
1091 case TARGET_OBJECT_MEMORY:
1092 return gdbsim_xfer_memory (this, readbuf, writebuf, offset, len,
1093 xfered_len);
1095 default:
1096 return TARGET_XFER_E_IO;
1100 void
1101 gdbsim_target::files_info ()
1103 struct sim_inferior_data *sim_data
1104 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);
1105 const char *file = "nothing";
1107 if (current_program_space->exec_bfd ())
1108 file = bfd_get_filename (current_program_space->exec_bfd ());
1110 if (remote_debug)
1111 gdb_printf (gdb_stdlog, "gdbsim_files_info: file \"%s\"\n", file);
1113 if (current_program_space->exec_bfd ())
1115 gdb_printf ("\tAttached to %s running program %s\n",
1116 target_shortname (), file);
1117 sim_info (sim_data->gdbsim_desc, 0);
1121 /* Clear the simulator's notion of what the break points are. */
1123 void
1124 gdbsim_target::mourn_inferior ()
1126 if (remote_debug)
1127 gdb_printf (gdb_stdlog, "gdbsim_mourn_inferior:\n");
1129 remove_breakpoints ();
1130 generic_mourn_inferior ();
1133 /* Pass the command argument through to the simulator verbatim. The
1134 simulator must do any command interpretation work. */
1136 static void
1137 simulator_command (const char *args, int from_tty)
1139 struct sim_inferior_data *sim_data;
1141 /* We use inferior_data() instead of get_sim_inferior_data() here in
1142 order to avoid attaching a sim_inferior_data struct to an
1143 inferior unnecessarily. The reason we take such care here is due
1144 to the fact that this function, simulator_command(), may be called
1145 even when the sim target is not active. If we were to use
1146 get_sim_inferior_data() here, it is possible that this call would
1147 be made either prior to gdbsim_open() or after gdbsim_close(),
1148 thus allocating memory that would not be garbage collected until
1149 the ultimate destruction of the associated inferior. */
1151 sim_data = sim_inferior_data_key.get (current_inferior ());
1152 if (sim_data == NULL || sim_data->gdbsim_desc == NULL)
1155 /* PREVIOUSLY: The user may give a command before the simulator
1156 is opened. [...] (??? assuming of course one wishes to
1157 continue to allow commands to be sent to unopened simulators,
1158 which isn't entirely unreasonable). */
1160 /* The simulator is a builtin abstraction of a remote target.
1161 Consistent with that model, access to the simulator, via sim
1162 commands, is restricted to the period when the channel to the
1163 simulator is open. */
1165 error (_("Not connected to the simulator target"));
1168 sim_do_command (sim_data->gdbsim_desc, args);
1170 /* Invalidate the register cache, in case the simulator command does
1171 something funny. */
1172 registers_changed ();
1175 static void
1176 sim_command_completer (struct cmd_list_element *ignore,
1177 completion_tracker &tracker,
1178 const char *text, const char *word)
1180 struct sim_inferior_data *sim_data;
1182 sim_data = sim_inferior_data_key.get (current_inferior ());
1183 if (sim_data == NULL || sim_data->gdbsim_desc == NULL)
1184 return;
1186 /* sim_complete_command returns a NULL-terminated malloc'ed array of
1187 malloc'ed strings. */
1188 struct sim_completions_deleter
1190 void operator() (char **ptr) const
1192 for (size_t i = 0; ptr[i] != NULL; i++)
1193 xfree (ptr[i]);
1194 xfree (ptr);
1198 std::unique_ptr<char *[], sim_completions_deleter> sim_completions
1199 (sim_complete_command (sim_data->gdbsim_desc, text, word));
1200 if (sim_completions == NULL)
1201 return;
1203 /* Count the elements and add completions from tail to head because
1204 below we'll swap elements out of the array in case add_completion
1205 throws and the deleter deletes until it finds a NULL element. */
1206 size_t count = 0;
1207 while (sim_completions[count] != NULL)
1208 count++;
1210 for (size_t i = count; i > 0; i--)
1212 gdb::unique_xmalloc_ptr<char> match (sim_completions[i - 1]);
1213 sim_completions[i - 1] = NULL;
1214 tracker.add_completion (std::move (match));
1218 /* Check to see if a thread is still alive. */
1220 bool
1221 gdbsim_target::thread_alive (ptid_t ptid)
1223 struct sim_inferior_data *sim_data
1224 = get_inferior_data_by_ptid (ptid, SIM_INSTANCE_NOT_NEEDED);
1226 if (sim_data == NULL)
1227 return false;
1229 if (ptid == sim_data->remote_sim_ptid)
1230 /* The simulators' task is always alive. */
1231 return true;
1233 return false;
1236 /* Convert a thread ID to a string. */
1238 std::string
1239 gdbsim_target::pid_to_str (ptid_t ptid)
1241 return normal_pid_to_str (ptid);
1244 /* Simulator memory may be accessed after the program has been loaded. */
1246 bool
1247 gdbsim_target::has_all_memory ()
1249 struct sim_inferior_data *sim_data
1250 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);
1252 if (!sim_data->program_loaded)
1253 return false;
1255 return true;
1258 bool
1259 gdbsim_target::has_memory ()
1261 struct sim_inferior_data *sim_data
1262 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NOT_NEEDED);
1264 if (!sim_data->program_loaded)
1265 return false;
1267 return true;
1270 /* Get memory map from the simulator. */
1272 std::vector<mem_region>
1273 gdbsim_target::memory_map ()
1275 struct sim_inferior_data *sim_data
1276 = get_sim_inferior_data (current_inferior (), SIM_INSTANCE_NEEDED);
1277 std::vector<mem_region> result;
1278 gdb::unique_xmalloc_ptr<char> text (sim_memory_map (sim_data->gdbsim_desc));
1280 if (text != nullptr)
1281 result = parse_memory_map (text.get ());
1283 return result;
1286 void _initialize_remote_sim ();
1287 void
1288 _initialize_remote_sim ()
1290 struct cmd_list_element *c;
1292 add_target (gdbsim_target_info, gdbsim_target_open);
1294 c = add_com ("sim", class_obscure, simulator_command,
1295 _("Send a command to the simulator."));
1296 set_cmd_completer (c, sim_command_completer);