gdb/interps.c

   1 /* Manages interpreters for GDB, the GNU debugger.
   2
   3    Copyright (C) 2000-2024 Free Software Foundation, Inc.
   4
   5    Written by Jim Ingham <jingham@apple.com> of Apple Computer, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 /* This is just a first cut at separating out the "interpreter"
  23    functions of gdb into self-contained modules.  There are a couple
  24    of open areas that need to be sorted out:
  25
  26    1) The interpreter explicitly contains a UI_OUT, and can insert itself
  27    into the event loop, but it doesn't explicitly contain hooks for readline.
  28    I did this because it seems to me many interpreters won't want to use
  29    the readline command interface, and it is probably simpler to just let
  30    them take over the input in their resume proc.  */
  31
  32 #include "gdbcmd.h"
  33 #include "ui-out.h"
  34 #include "gdbsupport/event-loop.h"
  35 #include "event-top.h"
  36 #include "interps.h"
  37 #include "completer.h"
  38 #include "ui.h"
  39 #include "main.h"
  40 #include "gdbsupport/buildargv.h"
  41 #include "gdbsupport/scope-exit.h"
  42
  43 /* The magic initialization routine for this module.  */
  44
  45 static struct interp *interp_lookup_existing (struct ui *ui,
  46                                               const char *name);
  47
  48 interp::interp (const char *name)
  49   : m_name (name)
  50 {
  51 }
  52
  53 interp::~interp () = default;
  54
  55 /* An interpreter factory.  Maps an interpreter name to the factory
  56    function that instantiates an interpreter by that name.  */
  57
  58 struct interp_factory
  59 {
  60   interp_factory (const char *name_, interp_factory_func func_)
  61   : name (name_), func (func_)
  62   {}
  63
  64   /* This is the name in "-i=INTERP" and "interpreter-exec INTERP".  */
  65   const char *name;
  66
  67   /* The function that creates the interpreter.  */
  68   interp_factory_func func;
  69 };
  70
  71 /* The registered interpreter factories.  */
  72 static std::vector<interp_factory> interpreter_factories;
  73
  74 /* See interps.h.  */
  75
  76 void
  77 interp_factory_register (const char *name, interp_factory_func func)
  78 {
  79   /* Assert that no factory for NAME is already registered.  */
  80   for (const interp_factory &f : interpreter_factories)
  81     if (strcmp (f.name, name) == 0)
  82       {
  83         internal_error (_("interpreter factory already registered: \"%s\"\n"),
  84                         name);
  85       }
  86
  87   interpreter_factories.emplace_back (name, func);
  88 }
  89
  90 /* Add interpreter INTERP to the gdb interpreter list.  The
  91    interpreter must not have previously been added.  */
  92 static void
  93 interp_add (struct ui *ui, struct interp *interp)
  94 {
  95   gdb_assert (interp_lookup_existing (ui, interp->name ()) == NULL);
  96
  97   ui->interp_list.push_back (*interp);
  98 }
  99
 100 /* This sets the current interpreter to be INTERP.  If INTERP has not
 101    been initialized, then this will also run the init method.
 102
 103    The TOP_LEVEL parameter tells if this new interpreter is
 104    the top-level one.  The top-level is what is requested
 105    on the command line, and is responsible for reporting general
 106    notification about target state changes.  For example, if
 107    MI is the top-level interpreter, then it will always report
 108    events such as target stops and new thread creation, even if they
 109    are caused by CLI commands.  */
 110
 111 static void
 112 interp_set (struct interp *interp, bool top_level)
 113 {
 114   struct interp *old_interp = current_ui->current_interpreter;
 115
 116   /* If we already have an interpreter, then trying to
 117      set top level interpreter is kinda pointless.  */
 118   gdb_assert (!top_level || !current_ui->current_interpreter);
 119   gdb_assert (!top_level || !current_ui->top_level_interpreter);
 120
 121   if (old_interp != NULL)
 122     {
 123       current_uiout->flush ();
 124       old_interp->suspend ();
 125     }
 126
 127   current_ui->current_interpreter = interp;
 128   if (top_level)
 129     current_ui->top_level_interpreter = interp;
 130
 131   if (interpreter_p != interp->name ())
 132     interpreter_p = interp->name ();
 133
 134   /* Run the init proc.  */
 135   if (!interp->inited)
 136     {
 137       interp->init (top_level);
 138       interp->inited = true;
 139     }
 140
 141   /* Do this only after the interpreter is initialized.  */
 142   current_uiout = interp->interp_ui_out ();
 143
 144   /* Clear out any installed interpreter hooks/event handlers.  */
 145   clear_interpreter_hooks ();
 146
 147   interp->resume ();
 148 }
 149
 150 /* Look up the interpreter for NAME.  If no such interpreter exists,
 151    return NULL, otherwise return a pointer to the interpreter.  */
 152
 153 static struct interp *
 154 interp_lookup_existing (struct ui *ui, const char *name)
 155 {
 156   for (interp &interp : ui->interp_list)
 157     if (strcmp (interp.name (), name) == 0)
 158       return &interp;
 159
 160   return nullptr;
 161 }
 162
 163 /* See interps.h.  */
 164
 165 struct interp *
 166 interp_lookup (struct ui *ui, const char *name)
 167 {
 168   if (name == NULL || strlen (name) == 0)
 169     return NULL;
 170
 171   /* Only create each interpreter once per top level.  */
 172   struct interp *interp = interp_lookup_existing (ui, name);
 173   if (interp != NULL)
 174     return interp;
 175
 176   for (const interp_factory &factory : interpreter_factories)
 177     if (strcmp (factory.name, name) == 0)
 178       {
 179         interp = factory.func (factory.name);
 180         interp_add (ui, interp);
 181         return interp;
 182       }
 183
 184   return NULL;
 185 }
 186
 187 /* See interps.h.  */
 188
 189 void
 190 set_top_level_interpreter (const char *name)
 191 {
 192   /* Find it.  */
 193   struct interp *interp = interp_lookup (current_ui, name);
 194
 195   if (interp == NULL)
 196     error (_("Interpreter `%s' unrecognized"), name);
 197   /* Install it.  */
 198   interp_set (interp, true);
 199 }
 200
 201 void
 202 current_interp_set_logging (ui_file_up logfile, bool logging_redirect,
 203                             bool debug_redirect)
 204 {
 205   struct interp *interp = current_ui->current_interpreter;
 206
 207   interp->set_logging (std::move (logfile), logging_redirect, debug_redirect);
 208 }
 209
 210 /* Temporarily overrides the current interpreter.  */
 211 struct interp *
 212 scoped_restore_interp::set_interp (const char *name)
 213 {
 214   struct interp *interp = interp_lookup (current_ui, name);
 215   struct interp *old_interp = current_ui->current_interpreter;
 216
 217   if (interp)
 218     current_ui->current_interpreter = interp;
 219
 220   return old_interp;
 221 }
 222
 223 /* Returns true if the current interp is the passed in name.  */
 224 int
 225 current_interp_named_p (const char *interp_name)
 226 {
 227   interp *interp = current_ui->current_interpreter;
 228
 229   if (interp != NULL)
 230     return (strcmp (interp->name (), interp_name) == 0);
 231
 232   return 0;
 233 }
 234
 235 /* The interpreter that was active when a command was executed.
 236    Normally that'd always be CURRENT_INTERPRETER, except that MI's
 237    -interpreter-exec command doesn't actually flip the current
 238    interpreter when running its sub-command.  The
 239    `command_interpreter' global tracks when interp_exec is called
 240    (IOW, when -interpreter-exec is called).  If that is set, it is
 241    INTERP in '-interpreter-exec INTERP "CMD"' or in 'interpreter-exec
 242    INTERP "CMD".  Otherwise, interp_exec isn't active, and so the
 243    interpreter running the command is the current interpreter.  */
 244
 245 struct interp *
 246 command_interp (void)
 247 {
 248   if (current_ui->command_interpreter != nullptr)
 249     return current_ui->command_interpreter;
 250   else
 251     return current_ui->current_interpreter;
 252 }
 253
 254 /* interp_exec - This executes COMMAND_STR in the current
 255    interpreter.  */
 256
 257 void
 258 interp_exec (struct interp *interp, const char *command_str)
 259 {
 260   /* See `command_interp' for why we do this.  */
 261   scoped_restore save_command_interp
 262     = make_scoped_restore (&current_ui->command_interpreter, interp);
 263
 264   interp->exec (command_str);
 265 }
 266
 267 /* A convenience routine that nulls out all the common command hooks.
 268    Use it when removing your interpreter in its suspend proc.  */
 269 void
 270 clear_interpreter_hooks (void)
 271 {
 272   deprecated_print_frame_info_listing_hook = 0;
 273   /*print_frame_more_info_hook = 0; */
 274   deprecated_query_hook = 0;
 275   deprecated_readline_begin_hook = 0;
 276   deprecated_readline_hook = 0;
 277   deprecated_readline_end_hook = 0;
 278   deprecated_context_hook = 0;
 279   deprecated_call_command_hook = 0;
 280   deprecated_error_begin_hook = 0;
 281 }
 282
 283 static void
 284 interpreter_exec_cmd (const char *args, int from_tty)
 285 {
 286   struct interp *interp_to_use;
 287   unsigned int nrules;
 288   unsigned int i;
 289
 290   /* Interpreters may clobber stdout/stderr (e.g.  in mi_interp::resume at time
 291      of writing), preserve their state here.  */
 292   scoped_restore save_stdout = make_scoped_restore (&gdb_stdout);
 293   scoped_restore save_stderr = make_scoped_restore (&gdb_stderr);
 294   scoped_restore save_stdlog = make_scoped_restore (&gdb_stdlog);
 295   scoped_restore save_stdtarg = make_scoped_restore (&gdb_stdtarg);
 296   scoped_restore save_stdtargerr = make_scoped_restore (&gdb_stdtargerr);
 297
 298   if (args == NULL)
 299     error_no_arg (_("interpreter-exec command"));
 300
 301   gdb_argv prules (args);
 302   nrules = prules.count ();
 303
 304   if (nrules < 2)
 305     error (_("Usage: interpreter-exec INTERPRETER COMMAND..."));
 306
 307   interp *old_interp = current_ui->current_interpreter;
 308
 309   interp_to_use = interp_lookup (current_ui, prules[0]);
 310   if (interp_to_use == NULL)
 311     error (_("Could not find interpreter \"%s\"."), prules[0]);
 312
 313   interp_set (interp_to_use, false);
 314   SCOPE_EXIT
 315     {
 316       interp_set (old_interp, false);
 317     };
 318
 319   for (i = 1; i < nrules; i++)
 320     interp_exec (interp_to_use, prules[i]);
 321 }
 322
 323 /* See interps.h.  */
 324
 325 void
 326 interpreter_completer (struct cmd_list_element *ignore,
 327                        completion_tracker &tracker,
 328                        const char *text, const char *word)
 329 {
 330   int textlen = strlen (text);
 331
 332   for (const interp_factory &interp : interpreter_factories)
 333     {
 334       if (strncmp (interp.name, text, textlen) == 0)
 335         {
 336           tracker.add_completion
 337             (make_completion_match_str (interp.name, text, word));
 338         }
 339     }
 340 }
 341
 342 struct interp *
 343 top_level_interpreter (void)
 344 {
 345   return current_ui->top_level_interpreter;
 346 }
 347
 348 /* See interps.h.  */
 349
 350 struct interp *
 351 current_interpreter (void)
 352 {
 353   return current_ui->current_interpreter;
 354 }
 355
 356 /* Helper interps_notify_* functions.  Call METHOD on the top-level interpreter
 357    of all UIs.  */
 358
 359 template <typename MethodType, typename ...Args>
 360 void
 361 interps_notify (MethodType method, Args&&... args)
 362 {
 363   SWITCH_THRU_ALL_UIS ()
 364     {
 365       interp *tli = top_level_interpreter ();
 366       if (tli != nullptr)
 367         (tli->*method) (std::forward<Args> (args)...);
 368     }
 369 }
 370
 371 /* See interps.h.  */
 372
 373 void
 374 interps_notify_signal_received (gdb_signal sig)
 375 {
 376   interps_notify (&interp::on_signal_received, sig);
 377 }
 378
 379 /* See interps.h.  */
 380
 381 void
 382 interps_notify_signal_exited (gdb_signal sig)
 383 {
 384   interps_notify (&interp::on_signal_exited, sig);
 385 }
 386
 387 /* See interps.h.  */
 388
 389 void
 390 interps_notify_no_history ()
 391 {
 392   interps_notify (&interp::on_no_history);
 393 }
 394
 395 /* See interps.h.  */
 396
 397 void
 398 interps_notify_normal_stop (bpstat *bs, int print_frame)
 399 {
 400   interps_notify (&interp::on_normal_stop, bs, print_frame);
 401 }
 402
 403 /* See interps.h.  */
 404
 405 void
 406 interps_notify_exited (int status)
 407 {
 408   interps_notify (&interp::on_exited, status);
 409 }
 410
 411 /* See interps.h.  */
 412
 413 void
 414 interps_notify_user_selected_context_changed (user_selected_what selection)
 415 {
 416   interps_notify (&interp::on_user_selected_context_changed, selection);
 417 }
 418
 419 /* See interps.h.  */
 420
 421 void
 422 interps_notify_new_thread (thread_info *t)
 423 {
 424   interps_notify (&interp::on_new_thread, t);
 425 }
 426
 427 /* See interps.h.  */
 428
 429 void
 430 interps_notify_thread_exited (thread_info *t,
 431                               std::optional<ULONGEST> exit_code,
 432                               int silent)
 433 {
 434   interps_notify (&interp::on_thread_exited, t, exit_code, silent);
 435 }
 436
 437 /* See interps.h.  */
 438
 439 void
 440 interps_notify_inferior_added (inferior *inf)
 441 {
 442   interps_notify (&interp::on_inferior_added, inf);
 443 }
 444
 445 /* See interps.h.  */
 446
 447 void
 448 interps_notify_inferior_appeared (inferior *inf)
 449 {
 450   interps_notify (&interp::on_inferior_appeared, inf);
 451 }
 452
 453 /* See interps.h.  */
 454
 455 void
 456 interps_notify_inferior_disappeared (inferior *inf)
 457 {
 458   interps_notify (&interp::on_inferior_disappeared, inf);
 459 }
 460
 461 /* See interps.h.  */
 462
 463 void
 464 interps_notify_inferior_removed (inferior *inf)
 465 {
 466   interps_notify (&interp::on_inferior_removed, inf);
 467 }
 468
 469 /* See interps.h.  */
 470
 471 void
 472 interps_notify_record_changed (inferior *inf, int started, const char *method,
 473                                const char *format)
 474 {
 475   interps_notify (&interp::on_record_changed, inf, started, method, format);
 476 }
 477
 478 /* See interps.h.  */
 479
 480 void
 481 interps_notify_target_resumed (ptid_t ptid)
 482 {
 483   interps_notify (&interp::on_target_resumed, ptid);
 484 }
 485
 486 /* See interps.h.  */
 487
 488 void
 489 interps_notify_solib_loaded (const solib &so)
 490 {
 491   interps_notify (&interp::on_solib_loaded, so);
 492 }
 493
 494 /* See interps.h.  */
 495
 496 void
 497 interps_notify_solib_unloaded (const solib &so)
 498 {
 499   interps_notify (&interp::on_solib_unloaded, so);
 500 }
 501
 502 /* See interps.h.  */
 503
 504 void
 505 interps_notify_traceframe_changed (int tfnum, int tpnum)
 506 {
 507   interps_notify (&interp::on_traceframe_changed, tfnum, tpnum);
 508 }
 509
 510 /* See interps.h.  */
 511
 512 void
 513 interps_notify_tsv_created (const trace_state_variable *tsv)
 514 {
 515   interps_notify (&interp::on_tsv_created, tsv);
 516 }
 517
 518 /* See interps.h.  */
 519
 520 void
 521 interps_notify_tsv_deleted (const trace_state_variable *tsv)
 522 {
 523   interps_notify (&interp::on_tsv_deleted, tsv);
 524 }
 525
 526 /* See interps.h.  */
 527
 528 void
 529 interps_notify_tsv_modified (const trace_state_variable *tsv)
 530 {
 531   interps_notify (&interp::on_tsv_modified, tsv);
 532 }
 533
 534 /* See interps.h.  */
 535
 536 void
 537 interps_notify_breakpoint_created (breakpoint *b)
 538 {
 539   interps_notify (&interp::on_breakpoint_created, b);
 540 }
 541
 542 /* See interps.h.  */
 543
 544 void
 545 interps_notify_breakpoint_deleted (breakpoint *b)
 546 {
 547   interps_notify (&interp::on_breakpoint_deleted, b);
 548 }
 549
 550 /* See interps.h.  */
 551
 552 void
 553 interps_notify_breakpoint_modified (breakpoint *b)
 554 {
 555   interps_notify (&interp::on_breakpoint_modified, b);
 556 }
 557
 558 /* See interps.h.  */
 559
 560 void
 561 interps_notify_param_changed (const char *param, const char *value)
 562 {
 563   interps_notify (&interp::on_param_changed, param, value);
 564 }
 565
 566 /* See interps.h.  */
 567
 568 void
 569 interps_notify_memory_changed (inferior *inf, CORE_ADDR addr, ssize_t len,
 570                                const bfd_byte *data)
 571 {
 572   interps_notify (&interp::on_memory_changed, inf, addr, len, data);
 573 }
 574
 575 /* This just adds the "interpreter-exec" command.  */
 576 void _initialize_interpreter ();
 577 void
 578 _initialize_interpreter ()
 579 {
 580   struct cmd_list_element *c;
 581
 582   c = add_cmd ("interpreter-exec", class_support,
 583                interpreter_exec_cmd, _("\
 584 Execute a command in an interpreter.\n\
 585 Usage: interpreter-exec INTERPRETER COMMAND...\n\
 586 The first argument is the name of the interpreter to use.\n\
 587 The following arguments are the commands to execute.\n\
 588 A command can have arguments, separated by spaces.\n\
 589 These spaces must be escaped using \\ or the command\n\
 590 and its arguments must be enclosed in double quotes."), &cmdlist);
 591   set_cmd_completer (c, interpreter_completer);
 592 }