lily/context.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2004--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "context.hh"
  21
  22 #include "context-def.hh"
  23 #include "dispatcher.hh"
  24 #include "global-context.hh"
  25 #include "international.hh"
  26 #include "ly-smobs.icc"
  27 #include "main.hh"
  28 #include "output-def.hh"
  29 #include "profile.hh"
  30 #include "program-option.hh"
  31 #include "scm-hash.hh"
  32 #include "translator-group.hh"
  33 #include "warn.hh"
  34
  35 bool
  36 Context::is_removable () const
  37 {
  38   return context_list_ == SCM_EOL && ! iterator_count_
  39     && !dynamic_cast<Global_context const *> (daddy_context_);
  40 }
  41
  42 void
  43 Context::check_removal ()
  44 {
  45   for (SCM p = context_list_; scm_is_pair (p); p = scm_cdr (p))
  46     {
  47       Context *ctx = unsmob_context (scm_car (p));
  48
  49       ctx->check_removal ();
  50       if (ctx->is_removable ())
  51         {
  52           recurse_over_translators (ctx, &Translator::finalize,
  53                                     &Translator_group::finalize,
  54                                     UP);
  55           send_stream_event (ctx, "RemoveContext", 0, 0);
  56         }
  57     }
  58 }
  59
  60 Context::Context (Context const & /* src */)
  61 {
  62   assert (false);
  63 }
  64
  65 Scheme_hash_table *
  66 Context::properties_dict () const
  67 {
  68   return Scheme_hash_table::unsmob (properties_scm_);
  69 }
  70
  71 void
  72 Context::add_context (Context *child)
  73 {
  74   context_list_ = ly_append2 (context_list_,
  75                               scm_cons (child->self_scm (), SCM_EOL));
  76
  77   child->daddy_context_ = this;
  78   this->events_below_->register_as_listener (child->events_below_);
  79 }
  80
  81
  82 Context::Context ()
  83 {
  84   daddy_context_ = 0;
  85   aliases_ = SCM_EOL;
  86   iterator_count_ = 0;
  87   implementation_ = 0;
  88   properties_scm_ = SCM_EOL;
  89   accepts_list_ = SCM_EOL;
  90   context_list_ = SCM_EOL;
  91   definition_ = SCM_EOL;
  92   definition_mods_ = SCM_EOL;
  93   event_source_ = 0;
  94   events_below_ = 0;
  95
  96   smobify_self ();
  97
  98   Scheme_hash_table *tab = new Scheme_hash_table;
  99   properties_scm_ = tab->unprotect ();
 100   event_source_ = new Dispatcher ();
 101   event_source_->unprotect ();
 102   events_below_ = new Dispatcher ();
 103   events_below_->unprotect ();
 104 }
 105
 106 /* TODO:  this shares code with find_create_context ().  */
 107 Context *
 108 Context::create_unique_context (SCM name, string id, SCM operations)
 109 {
 110   /*
 111     Don't create multiple score contexts.
 112   */
 113   Global_context *gthis = dynamic_cast<Global_context *> (this);
 114   if (gthis && gthis->get_score_context ())
 115     return gthis->get_score_context ()->create_unique_context (name, id, operations);
 116
 117   vector<Context_def *> path = path_to_acceptable_context (name);
 118   if (path.size ())
 119     {
 120       Context *current = this;
 121
 122       // Iterate through the path and create all of the implicit contexts.
 123       for (vsize i = 0; i < path.size (); i++)
 124         {
 125           SCM ops = SCM_EOL;
 126           string id_str = "\\new";
 127           if (i == path.size () - 1)
 128             {
 129               ops = operations;
 130               id_str = id;
 131             }
 132           current = current->create_context (path[i],
 133                                              id_str,
 134                                              ops);
 135         }
 136
 137       return current;
 138     }
 139
 140   /*
 141     Don't go up to Global_context, because global goes down to the
 142     Score context
 143   */
 144   Context *ret = 0;
 145   if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
 146     ret = daddy_context_->create_unique_context (name, id, operations);
 147   else
 148     {
 149       warning (_f ("cannot find or create new `%s'",
 150                    ly_symbol2string (name).c_str ()));
 151       ret = 0;
 152     }
 153   return ret;
 154 }
 155
 156 Context *
 157 Context::find_create_context (SCM n, string id, SCM operations)
 158 {
 159   /*
 160     Don't create multiple score contexts.
 161   */
 162   Global_context *gthis = dynamic_cast<Global_context *> (this);
 163   if (gthis && gthis->get_score_context ())
 164     return gthis->get_score_context ()->find_create_context (n, id, operations);
 165
 166   if (Context *existing = find_context_below (this, n, id))
 167     return existing;
 168
 169   if (n == ly_symbol2scm ("Bottom"))
 170     {
 171       Context *tg = get_default_interpreter (id);
 172       return tg;
 173     }
 174
 175   vector<Context_def*> path = path_to_acceptable_context (n);
 176
 177   if (path.size ())
 178     {
 179       Context *current = this;
 180
 181       // start at 1.  The first one (index 0) will be us.
 182       for (vsize i = 0; i < path.size (); i++)
 183         {
 184           SCM ops = (i == path.size () -1) ? operations : SCM_EOL;
 185
 186           string this_id = "";
 187           if (i == path.size () -1)
 188             this_id = id;
 189
 190           current = current->create_context (path[i],
 191                                              this_id,
 192                                              ops);
 193         }
 194
 195       return current;
 196     }
 197
 198   /*
 199     Don't go up to Global_context, because global goes down to the
 200     Score context
 201   */
 202   Context *ret = 0;
 203   if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
 204     ret = daddy_context_->find_create_context (n, id, operations);
 205   else
 206     {
 207       warning (_f ("cannot find or create `%s' called `%s'",
 208                    ly_symbol2string (n).c_str (), id));
 209       ret = 0;
 210     }
 211   return ret;
 212 }
 213
 214 IMPLEMENT_LISTENER (Context, acknowledge_infant);
 215 void
 216 Context::acknowledge_infant (SCM sev)
 217 {
 218   infant_event_ = unsmob_stream_event (sev);
 219 }
 220
 221 IMPLEMENT_LISTENER (Context, set_property_from_event);
 222 void
 223 Context::set_property_from_event (SCM sev)
 224 {
 225   Stream_event *ev = unsmob_stream_event (sev);
 226
 227   SCM sym = ev->get_property ("symbol");
 228   if (scm_is_symbol (sym))
 229     {
 230       SCM val = ev->get_property ("value");
 231       bool ok = true;
 232       if (val != SCM_EOL)
 233         ok = type_check_assignment (sym, val, ly_symbol2scm ("translation-type?"));
 234       if (ok)
 235         set_property (sym, val);
 236     }
 237 }
 238
 239 IMPLEMENT_LISTENER (Context, unset_property_from_event);
 240 void
 241 Context::unset_property_from_event (SCM sev)
 242 {
 243   Stream_event *ev = unsmob_stream_event (sev);
 244
 245   SCM sym = ev->get_property ("symbol");
 246   type_check_assignment (sym, SCM_EOL, ly_symbol2scm ("translation-type?"));
 247   unset_property (sym);
 248 }
 249
 250 /*
 251   Creates a new context from a CreateContext event, and sends an
 252   AnnounceNewContext event to this context.
 253 */
 254 IMPLEMENT_LISTENER (Context, create_context_from_event);
 255 void
 256 Context::create_context_from_event (SCM sev)
 257 {
 258   Stream_event *ev = unsmob_stream_event (sev);
 259
 260   string id = ly_scm2string (ev->get_property ("id"));
 261   SCM ops = ev->get_property ("ops");
 262   SCM type_scm = ev->get_property ("type");
 263   string type = ly_symbol2string (type_scm);
 264
 265   vector<Context_def*> path = path_to_acceptable_context (type_scm);
 266
 267   if (path.size () != 1)
 268     {
 269       programming_error (_f ("Invalid CreateContext event: Cannot create %s context", type.c_str ()));
 270       return;
 271     }
 272   Context_def *cdef = path[0];
 273
 274   Context *new_context = cdef->instantiate (ops);
 275
 276   new_context->id_string_ = id;
 277
 278   /* Register various listeners:
 279       - Make the new context hear events that universally affect contexts
 280       - connect events_below etc. properly */
 281   /* We want to be the first ones to hear our own events. Therefore, wait
 282      before registering events_below_ */
 283   new_context->event_source ()->
 284     add_listener (GET_LISTENER (new_context->create_context_from_event),
 285                   ly_symbol2scm ("CreateContext"));
 286   new_context->event_source ()->
 287     add_listener (GET_LISTENER (new_context->remove_context),
 288                   ly_symbol2scm ("RemoveContext"));
 289   new_context->event_source ()->
 290     add_listener (GET_LISTENER (new_context->change_parent),
 291                   ly_symbol2scm ("ChangeParent"));
 292   new_context->event_source ()->
 293     add_listener (GET_LISTENER (new_context->set_property_from_event),
 294                   ly_symbol2scm ("SetProperty"));
 295   new_context->event_source ()->
 296     add_listener (GET_LISTENER (new_context->unset_property_from_event),
 297                   ly_symbol2scm ("UnsetProperty"));
 298
 299   new_context->events_below_->register_as_listener (new_context->event_source_);
 300   this->add_context (new_context);
 301
 302   new_context->unprotect ();
 303
 304   Context_def *td = unsmob_context_def (new_context->definition_);
 305
 306   /* This cannot move before add_context (), because \override
 307      operations require that we are in the hierarchy.  */
 308   td->apply_default_property_operations (new_context);
 309   apply_property_operations (new_context, ops);
 310
 311   send_stream_event (this, "AnnounceNewContext", 0,
 312                      ly_symbol2scm ("context"), new_context->self_scm (),
 313                      ly_symbol2scm ("creator"), sev);
 314 }
 315
 316 vector<Context_def*>
 317 Context::path_to_acceptable_context (SCM name) const
 318 {
 319   // The 'accepts elements in definition_mods_ is a list of ('accepts string),
 320   // but the Context_def expects to see elements of the form ('accepts symbol).
 321   SCM accepts = SCM_EOL;
 322   for (SCM s = scm_reverse (definition_mods_); scm_is_pair (s); s = scm_cdr (s))
 323     if (scm_caar (s) == ly_symbol2scm ("accepts"))
 324       {
 325         SCM elt = scm_list_2 (scm_caar (s), scm_string_to_symbol (scm_cadar (s)));
 326         accepts = scm_cons (elt, accepts);
 327       }
 328
 329   return unsmob_context_def (definition_)->path_to_acceptable_context (name,
 330                                                                        get_output_def (),
 331                                                                        accepts);
 332
 333 }
 334
 335 Context *
 336 Context::create_context (Context_def *cdef,
 337                          string id,
 338                          SCM ops)
 339 {
 340   infant_event_ = 0;
 341   /* TODO: This is fairly misplaced. We can fix this when we have taken out all
 342      iterator specific stuff from the Context class */
 343   event_source_->
 344     add_listener (GET_LISTENER (acknowledge_infant),
 345                   ly_symbol2scm ("AnnounceNewContext"));
 346   /* The CreateContext creates a new context, and sends an announcement of the
 347      new context through another event. That event will be stored in
 348      infant_event_ to create a return value. */
 349   send_stream_event (this, "CreateContext", 0,
 350                      ly_symbol2scm ("ops"), ops,
 351                      ly_symbol2scm ("type"), cdef->get_context_name (),
 352                      ly_symbol2scm ("id"), ly_string2scm (id));
 353   event_source_->
 354     remove_listener (GET_LISTENER (acknowledge_infant),
 355                      ly_symbol2scm ("AnnounceNewContext"));
 356
 357   assert (infant_event_);
 358   SCM infant_scm = infant_event_->get_property ("context");
 359   Context *infant = unsmob_context (infant_scm);
 360
 361   if (!infant || infant->get_parent_context () != this)
 362     {
 363       programming_error ("create_context: can't locate newly created context");
 364       return 0;
 365     }
 366
 367   return infant;
 368 }
 369
 370 /*
 371   Default child context as a SCM string, or something else if there is
 372   none.
 373 */
 374 SCM
 375 Context::default_child_context_name () const
 376 {
 377   return scm_is_pair (accepts_list_)
 378     ? scm_car (accepts_list_)
 379     : SCM_EOL;
 380 }
 381
 382 bool
 383 Context::is_bottom_context () const
 384 {
 385   return !scm_is_symbol (default_child_context_name ());
 386 }
 387
 388 Context *
 389 Context::get_default_interpreter (string context_id)
 390 {
 391   if (!is_bottom_context ())
 392     {
 393       SCM nm = default_child_context_name ();
 394       SCM st = find_context_def (get_output_def (), nm);
 395
 396       string name = ly_symbol2string (nm);
 397       Context_def *t = unsmob_context_def (st);
 398       if (!t)
 399         {
 400           warning (_f ("cannot find or create: `%s'", name.c_str ()));
 401           t = unsmob_context_def (this->definition_);
 402         }
 403
 404       Context *tg = create_context (t, context_id, SCM_EOL);
 405       return tg->get_default_interpreter (context_id);
 406     }
 407   return this;
 408 }
 409
 410 /*
 411   PROPERTIES
 412 */
 413 Context *
 414 Context::where_defined (SCM sym, SCM *value) const
 415 {
 416 #ifndef NDEBUG
 417   if (profile_property_accesses)
 418     note_property_access (&context_property_lookup_table, sym);
 419 #endif
 420
 421   if (properties_dict ()->try_retrieve (sym, value))
 422     return (Context *)this;
 423
 424   return (daddy_context_) ? daddy_context_->where_defined (sym, value) : 0;
 425 }
 426
 427 /*
 428   return SCM_EOL when not found.
 429 */
 430 SCM
 431 Context::internal_get_property (SCM sym) const
 432 {
 433 #ifndef NDEBUG
 434   if (profile_property_accesses)
 435     note_property_access (&context_property_lookup_table, sym);
 436 #endif
 437
 438   SCM val = SCM_EOL;
 439   if (properties_dict ()->try_retrieve (sym, &val))
 440     return val;
 441
 442   if (daddy_context_)
 443     return daddy_context_->internal_get_property (sym);
 444
 445   return val;
 446 }
 447
 448 /*
 449 Called by the send_stream_event macro. props is a 0-terminated array of
 450 properties and corresponding values, interleaved. This method should not
 451 be called from any other place than the send_stream_event macro.
 452 */
 453 void
 454 Context::internal_send_stream_event (SCM type, Input *origin, SCM props[])
 455 {
 456   Stream_event *e = new Stream_event (type, origin);
 457   for (int i = 0; props[i]; i += 2)
 458     {
 459       e->set_property (props[i], props[i+1]);
 460     }
 461   event_source_->broadcast (e);
 462   e->unprotect ();
 463 }
 464
 465 bool
 466 Context::is_alias (SCM sym) const
 467 {
 468   if (sym == ly_symbol2scm ("Bottom")
 469       && !scm_is_pair (accepts_list_))
 470     return true;
 471   if (sym == unsmob_context_def (definition_)->get_context_name ())
 472     return true;
 473
 474   return scm_c_memq (sym, aliases_) != SCM_BOOL_F;
 475 }
 476
 477 void
 478 Context::add_alias (SCM sym)
 479 {
 480   aliases_ = scm_cons (sym, aliases_);
 481 }
 482
 483 /* we don't (yet) instrument context properties */
 484 void
 485 Context::instrumented_set_property (SCM sym, SCM val, const char*, int, const char*)
 486 {
 487   internal_set_property (sym, val);
 488 }
 489
 490 void
 491 Context::internal_set_property (SCM sym, SCM val)
 492 {
 493   if (do_internal_type_checking_global)
 494     assert (type_check_assignment (sym, val, ly_symbol2scm ("translation-type?")));
 495
 496   properties_dict ()->set (sym, val);
 497 }
 498
 499 /*
 500   TODO: look up to check whether we have inherited var?
 501 */
 502 void
 503 Context::unset_property (SCM sym)
 504 {
 505   properties_dict ()->remove (sym);
 506 }
 507
 508 IMPLEMENT_LISTENER (Context, change_parent);
 509 void
 510 Context::change_parent (SCM sev)
 511 {
 512   Stream_event *ev = unsmob_stream_event (sev);
 513   Context *to = unsmob_context (ev->get_property ("context"));
 514
 515   disconnect_from_parent ();
 516   to->add_context (this);
 517 }
 518
 519 /*
 520   Die. The next GC sweep should take care of the actual death.
 521  */
 522 IMPLEMENT_LISTENER (Context, remove_context);
 523 void
 524 Context::remove_context (SCM)
 525 {
 526   /* ugh, the translator group should listen to RemoveContext events by itself */
 527   Translator_group *impl = implementation ();
 528   if (impl)
 529     impl->disconnect_from_context ();
 530   disconnect_from_parent ();
 531 }
 532
 533 void
 534 Context::disconnect_from_parent ()
 535 {
 536   daddy_context_->events_below_->unregister_as_listener (this->events_below_);
 537   daddy_context_->context_list_ = scm_delq_x (this->self_scm (), daddy_context_->context_list_);
 538   daddy_context_ = 0;
 539 }
 540
 541 /*
 542   ID == "" means accept any ID.
 543 */
 544 Context *
 545 find_context_below (Context *where,
 546                     SCM type, string id)
 547 {
 548   if (where->is_alias (type))
 549     {
 550       if (id == "" || where->id_string () == id)
 551         return where;
 552     }
 553
 554   Context *found = 0;
 555   for (SCM s = where->children_contexts ();
 556        !found && scm_is_pair (s); s = scm_cdr (s))
 557     {
 558       Context *tr = unsmob_context (scm_car (s));
 559
 560       found = find_context_below (tr, type, id);
 561     }
 562
 563   return found;
 564 }
 565
 566 SCM
 567 Context::properties_as_alist () const
 568 {
 569   return properties_dict ()->to_alist ();
 570 }
 571
 572 SCM
 573 Context::context_name_symbol () const
 574 {
 575   Context_def *td = unsmob_context_def (definition_);
 576   return td->get_context_name ();
 577 }
 578
 579 string
 580 Context::context_name () const
 581 {
 582   return ly_symbol2string (context_name_symbol ());
 583 }
 584
 585 Context *
 586 Context::get_score_context () const
 587 {
 588   if (daddy_context_)
 589     return daddy_context_->get_score_context ();
 590   else
 591     return 0;
 592 }
 593
 594 Output_def *
 595 Context::get_output_def () const
 596 {
 597   return daddy_context_ ? daddy_context_->get_output_def () : 0;
 598 }
 599
 600 Context::~Context ()
 601 {
 602 }
 603
 604 Moment
 605 Context::now_mom () const
 606 {
 607   Context const *p = this;
 608   while (p->daddy_context_)
 609     p = p->daddy_context_;
 610
 611   return p->now_mom ();
 612 }
 613
 614 int
 615 Context::print_smob (SCM s, SCM port, scm_print_state *)
 616 {
 617   Context *sc = (Context *) SCM_CELL_WORD_1 (s);
 618
 619   scm_puts ("#<", port);
 620   scm_puts (sc->class_name (), port);
 621   if (Context_def *d = unsmob_context_def (sc->definition_))
 622     {
 623       scm_puts (" ", port);
 624       scm_display (d->get_context_name (), port);
 625     }
 626
 627   if (!sc->id_string_.empty ())
 628     {
 629       scm_puts ("=", port);
 630       scm_puts (sc->id_string_.c_str (), port);
 631     }
 632
 633   scm_puts (" ", port);
 634
 635   scm_display (sc->context_list_, port);
 636   scm_puts (" >", port);
 637
 638   return 1;
 639 }
 640
 641 SCM
 642 Context::mark_smob (SCM sm)
 643 {
 644   Context *me = (Context *) SCM_CELL_WORD_1 (sm);
 645
 646   scm_gc_mark (me->context_list_);
 647   scm_gc_mark (me->aliases_);
 648   scm_gc_mark (me->definition_);
 649   scm_gc_mark (me->definition_mods_);
 650   scm_gc_mark (me->properties_scm_);
 651   scm_gc_mark (me->accepts_list_);
 652
 653   if (me->implementation_)
 654     scm_gc_mark (me->implementation_->self_scm ());
 655
 656   if (me->event_source_)
 657     scm_gc_mark (me->event_source_->self_scm ());
 658
 659   if (me->events_below_)
 660     scm_gc_mark (me->events_below_->self_scm ());
 661
 662   return me->properties_scm_;
 663 }
 664
 665 IMPLEMENT_SMOBS (Context);
 666 IMPLEMENT_DEFAULT_EQUAL_P (Context);
 667 IMPLEMENT_TYPE_P (Context, "ly:context?");
 668
 669 Global_context *
 670 Context::get_global_context () const
 671 {
 672   if (dynamic_cast<Global_context *> ((Context *) this))
 673     return dynamic_cast<Global_context *> ((Context *) this);
 674
 675   if (daddy_context_)
 676     return daddy_context_->get_global_context ();
 677
 678   programming_error ("no Global context");
 679   return 0;
 680 }
 681
 682 Context *
 683 Context::get_parent_context () const
 684 {
 685   return daddy_context_;
 686 }
 687
 688 /*
 689   Ugh. Where to put this?
 690 */
 691 Rational
 692 measure_length (Context const *context)
 693 {
 694   SCM l = context->get_property ("measureLength");
 695   Rational length (1);
 696   if (unsmob_moment (l))
 697     length = unsmob_moment (l)->main_part_;
 698   return length;
 699 }
 700
 701 Moment
 702 measure_position (Context const *context)
 703 {
 704   SCM sm = context->get_property ("measurePosition");
 705
 706   Moment m = 0;
 707   if (unsmob_moment (sm))
 708     {
 709       m = *unsmob_moment (sm);
 710
 711       if (m.main_part_ < Rational (0))
 712         {
 713           Rational length (measure_length (context));
 714           while (m.main_part_ < Rational (0))
 715             m.main_part_ += length;
 716         }
 717     }
 718
 719   return m;
 720 }
 721
 722 /* Finds the measure position after a note of length DUR that
 723    begins at the current measure position. */
 724 Moment
 725 measure_position (Context const *context, Duration const *dur)
 726 {
 727   Moment pos = measure_position (context);
 728   Rational dur_length = dur ? dur->get_length () : Rational (0);
 729
 730   Moment end_pos = pos.grace_part_ < Rational(0)
 731     ? Moment(pos.main_part_, pos.grace_part_ + dur_length)
 732     : Moment(pos.main_part_ + dur_length, 0);
 733
 734   return end_pos;
 735 }
 736
 737 int
 738 measure_number (Context const *context)
 739 {
 740   SCM barnum = context->get_property ("internalBarNumber");
 741   SCM smp = context->get_property ("measurePosition");
 742
 743   int bn = robust_scm2int (barnum, 0);
 744   Moment mp = robust_scm2moment (smp, Moment (0));
 745   if (mp.main_part_ < Rational (0))
 746     bn--;
 747
 748   return bn;
 749 }
 750
 751
 752 void
 753 set_context_property_on_children (Context *trans, SCM sym, SCM val)
 754 {
 755   trans->set_property (sym, ly_deep_copy (val));
 756   for (SCM p = trans->children_contexts (); scm_is_pair (p); p = scm_cdr (p))
 757     {
 758       Context *trg = unsmob_context (scm_car (p));
 759       set_context_property_on_children (trg, sym, ly_deep_copy (val));
 760     }
 761 }
 762
 763 bool
 764 melisma_busy (Context *tr)
 765 {
 766   SCM melisma_properties = tr->get_property ("melismaBusyProperties");
 767   bool busy = false;
 768
 769   for (; !busy && scm_is_pair (melisma_properties);
 770        melisma_properties = scm_cdr (melisma_properties))
 771     busy = busy || to_boolean (tr->internal_get_property (scm_car (melisma_properties)));
 772
 773   return busy;
 774 }