lily/context.cc

   1 /*
   2   context.cc -- implement Context
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2004--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "context.hh"
  10
  11 #include "context-def.hh"
  12 #include "dispatcher.hh"
  13 #include "global-context.hh"
  14 #include "international.hh"
  15 #include "ly-smobs.icc"
  16 #include "main.hh"
  17 #include "output-def.hh"
  18 #include "profile.hh"
  19 #include "program-option.hh"
  20 #include "scm-hash.hh"
  21 #include "translator-group.hh"
  22 #include "warn.hh"
  23
  24 bool
  25 Context::is_removable () const
  26 {
  27   return context_list_ == SCM_EOL && ! iterator_count_
  28     && !dynamic_cast<Global_context const *> (daddy_context_);
  29 }
  30
  31 void
  32 Context::check_removal ()
  33 {
  34   for (SCM p = context_list_; scm_is_pair (p); p = scm_cdr (p))
  35     {
  36       Context *ctx = unsmob_context (scm_car (p));
  37
  38       ctx->check_removal ();
  39       if (ctx->is_removable ())
  40         {
  41           recurse_over_translators (ctx, &Translator::finalize,
  42                                     &Translator_group::finalize,
  43                                     UP);
  44           send_stream_event (ctx, "RemoveContext", 0, 0);
  45         }
  46     }
  47 }
  48
  49 Context::Context (Context const & /* src */)
  50 {
  51   assert (false);
  52 }
  53
  54 Scheme_hash_table *
  55 Context::properties_dict () const
  56 {
  57   return Scheme_hash_table::unsmob (properties_scm_);
  58 }
  59
  60 void
  61 Context::add_context (Context *child)
  62 {
  63   context_list_ = ly_append2 (context_list_,
  64                               scm_cons (child->self_scm (), SCM_EOL));
  65
  66   child->daddy_context_ = this;
  67   this->events_below_->register_as_listener (child->events_below_);
  68 }
  69
  70
  71 Context::Context ()
  72 {
  73   daddy_context_ = 0;
  74   aliases_ = SCM_EOL;
  75   iterator_count_ = 0;
  76   implementation_ = 0;
  77   properties_scm_ = SCM_EOL;
  78   accepts_list_ = SCM_EOL;
  79   context_list_ = SCM_EOL;
  80   definition_ = SCM_EOL;
  81   definition_mods_ = SCM_EOL;
  82   event_source_ = 0;
  83   events_below_ = 0;
  84
  85   smobify_self ();
  86
  87   Scheme_hash_table *tab = new Scheme_hash_table;
  88   properties_scm_ = tab->unprotect ();
  89   event_source_ = new Dispatcher ();
  90   event_source_->unprotect ();
  91   events_below_ = new Dispatcher ();
  92   events_below_->unprotect ();
  93 }
  94
  95 /* TODO:  this shares code with find_create_context ().  */
  96 Context *
  97 Context::create_unique_context (SCM name, string id, SCM operations)
  98 {
  99   /*
 100     Don't create multiple score contexts.
 101   */
 102   Global_context *gthis = dynamic_cast<Global_context *> (this);
 103   if (gthis && gthis->get_score_context ())
 104     return gthis->get_score_context ()->create_unique_context (name, id, operations);
 105
 106   vector<Context_def*> path = path_to_acceptable_context (name);
 107   if (path.size ())
 108     {
 109       Context *current = this;
 110
 111       // Iterate through the path and create all of the implicit contexts.
 112       for (vsize i = 0; i < path.size (); i++)
 113         {
 114           SCM ops = SCM_EOL;
 115           string id_str = "\\new";
 116           if (i == path.size () - 1)
 117             {
 118               ops = operations;
 119               id_str = id;
 120             }
 121           current = current->create_context (path[i],
 122                                              id_str,
 123                                              ops);
 124         }
 125
 126       return current;
 127     }
 128
 129   /*
 130     Don't go up to Global_context, because global goes down to the
 131     Score context
 132   */
 133   Context *ret = 0;
 134   if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
 135     ret = daddy_context_->create_unique_context (name, id, operations);
 136   else
 137     {
 138       warning (_f ("cannot find or create new `%s'",
 139                    ly_symbol2string (name).c_str ()));
 140       ret = 0;
 141     }
 142   return ret;
 143 }
 144
 145 Context *
 146 Context::find_create_context (SCM n, string id, SCM operations)
 147 {
 148   /*
 149     Don't create multiple score contexts.
 150   */
 151   Global_context *gthis = dynamic_cast<Global_context *> (this);
 152   if (gthis && gthis->get_score_context ())
 153     return gthis->get_score_context ()->find_create_context (n, id, operations);
 154
 155   if (Context *existing = find_context_below (this, n, id))
 156     return existing;
 157
 158   if (n == ly_symbol2scm ("Bottom"))
 159     {
 160       Context *tg = get_default_interpreter ();
 161       return tg;
 162     }
 163
 164   vector<Context_def*> path = path_to_acceptable_context (n);
 165
 166   if (path.size ())
 167     {
 168       Context *current = this;
 169
 170       // start at 1.  The first one (index 0) will be us.
 171       for (vsize i = 0; i < path.size (); i++)
 172         {
 173           SCM ops = (i == path.size () -1) ? operations : SCM_EOL;
 174
 175           string this_id = "";
 176           if (i == path.size () -1)
 177             this_id = id;
 178
 179           current = current->create_context (path[i],
 180                                              this_id,
 181                                              ops);
 182         }
 183
 184       return current;
 185     }
 186
 187   /*
 188     Don't go up to Global_context, because global goes down to the
 189     Score context
 190   */
 191   Context *ret = 0;
 192   if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
 193     ret = daddy_context_->find_create_context (n, id, operations);
 194   else
 195     {
 196       warning (_f ("cannot find or create `%s' called `%s'",
 197                    ly_symbol2string (n).c_str (), id));
 198       ret = 0;
 199     }
 200   return ret;
 201 }
 202
 203 IMPLEMENT_LISTENER (Context, acknowledge_infant);
 204 void
 205 Context::acknowledge_infant (SCM sev)
 206 {
 207   infant_event_ = unsmob_stream_event (sev);
 208 }
 209
 210 IMPLEMENT_LISTENER (Context, set_property_from_event);
 211 void
 212 Context::set_property_from_event (SCM sev)
 213 {
 214   Stream_event *ev = unsmob_stream_event (sev);
 215
 216   SCM sym = ev->get_property ("symbol");
 217   if (scm_is_symbol (sym))
 218     {
 219       SCM val = ev->get_property ("value");
 220       bool ok = true;
 221       if (val != SCM_EOL)
 222         ok = type_check_assignment (sym, val, ly_symbol2scm ("translation-type?"));
 223       if (ok)
 224         set_property (sym, val);
 225     }
 226 }
 227
 228 IMPLEMENT_LISTENER (Context, unset_property_from_event);
 229 void
 230 Context::unset_property_from_event (SCM sev)
 231 {
 232   Stream_event *ev = unsmob_stream_event (sev);
 233
 234   SCM sym = ev->get_property ("symbol");
 235   type_check_assignment (sym, SCM_EOL, ly_symbol2scm ("translation-type?"));
 236   unset_property (sym);
 237 }
 238
 239 /*
 240   Creates a new context from a CreateContext event, and sends an
 241   AnnounceNewContext event to this context.
 242 */
 243 IMPLEMENT_LISTENER (Context, create_context_from_event);
 244 void
 245 Context::create_context_from_event (SCM sev)
 246 {
 247   Stream_event *ev = unsmob_stream_event (sev);
 248
 249   string id = ly_scm2string (ev->get_property ("id"));
 250   SCM ops = ev->get_property ("ops");
 251   SCM type_scm = ev->get_property ("type");
 252   string type = ly_symbol2string (type_scm);
 253
 254   vector<Context_def*> path = path_to_acceptable_context (type_scm);
 255
 256   if (path.size () != 1)
 257     {
 258       programming_error (_f ("Invalid CreateContext event: Cannot create %s context", type.c_str ()));
 259       return;
 260     }
 261   Context_def *cdef = path[0];
 262
 263   Context *new_context = cdef->instantiate (ops);
 264
 265   new_context->id_string_ = id;
 266
 267   /* Register various listeners:
 268       - Make the new context hear events that universally affect contexts
 269       - connect events_below etc. properly */
 270   /* We want to be the first ones to hear our own events. Therefore, wait
 271      before registering events_below_ */
 272   new_context->event_source ()->
 273     add_listener (GET_LISTENER (new_context->create_context_from_event),
 274                   ly_symbol2scm ("CreateContext"));
 275   new_context->event_source ()->
 276     add_listener (GET_LISTENER (new_context->remove_context),
 277                   ly_symbol2scm ("RemoveContext"));
 278   new_context->event_source ()->
 279     add_listener (GET_LISTENER (new_context->change_parent),
 280                   ly_symbol2scm ("ChangeParent"));
 281   new_context->event_source ()->
 282     add_listener (GET_LISTENER (new_context->set_property_from_event),
 283                   ly_symbol2scm ("SetProperty"));
 284   new_context->event_source ()->
 285     add_listener (GET_LISTENER (new_context->unset_property_from_event),
 286                   ly_symbol2scm ("UnsetProperty"));
 287
 288   new_context->events_below_->register_as_listener (new_context->event_source_);
 289   this->add_context (new_context);
 290
 291   new_context->unprotect ();
 292
 293   Context_def *td = unsmob_context_def (new_context->definition_);
 294
 295   /* This cannot move before add_context (), because \override
 296      operations require that we are in the hierarchy.  */
 297   td->apply_default_property_operations (new_context);
 298   apply_property_operations (new_context, ops);
 299
 300   send_stream_event (this, "AnnounceNewContext", 0,
 301                      ly_symbol2scm ("context"), new_context->self_scm (),
 302                      ly_symbol2scm ("creator"), sev);
 303 }
 304
 305 vector<Context_def*>
 306 Context::path_to_acceptable_context (SCM name) const
 307 {
 308   // The 'accepts elements in definition_mods_ is a list of ('accepts string),
 309   // but the Context_def expects to see elements of the form ('accepts symbol).
 310   SCM accepts = SCM_EOL;
 311   for (SCM s = scm_reverse (definition_mods_); scm_is_pair (s); s = scm_cdr (s))
 312     if (scm_caar (s) == ly_symbol2scm ("accepts"))
 313       {
 314         SCM elt = scm_list_2 (scm_caar (s), scm_string_to_symbol (scm_cadar (s)));
 315         accepts = scm_cons (elt, accepts);
 316       }
 317
 318   return unsmob_context_def (definition_)->path_to_acceptable_context (name,
 319                                                                        get_output_def (),
 320                                                                        accepts);
 321
 322 }
 323
 324 Context *
 325 Context::create_context (Context_def *cdef,
 326                          string id,
 327                          SCM ops)
 328 {
 329   infant_event_ = 0;
 330   /* TODO: This is fairly misplaced. We can fix this when we have taken out all
 331      iterator specific stuff from the Context class */
 332   event_source_->
 333     add_listener (GET_LISTENER (acknowledge_infant),
 334                   ly_symbol2scm ("AnnounceNewContext"));
 335   /* The CreateContext creates a new context, and sends an announcement of the
 336      new context through another event. That event will be stored in
 337      infant_event_ to create a return value. */
 338   send_stream_event (this, "CreateContext", 0,
 339                      ly_symbol2scm ("ops"), ops,
 340                      ly_symbol2scm ("type"), cdef->get_context_name (),
 341                      ly_symbol2scm ("id"), ly_string2scm (id));
 342   event_source_->
 343     remove_listener (GET_LISTENER (acknowledge_infant),
 344                      ly_symbol2scm ("AnnounceNewContext"));
 345
 346   assert (infant_event_);
 347   SCM infant_scm = infant_event_->get_property ("context");
 348   Context *infant = unsmob_context (infant_scm);
 349
 350   if (!infant || infant->get_parent_context () != this)
 351     {
 352       programming_error ("create_context: can't locate newly created context");
 353       return 0;
 354     }
 355
 356   return infant;
 357 }
 358
 359 /*
 360   Default child context as a SCM string, or something else if there is
 361   none.
 362 */
 363 SCM
 364 Context::default_child_context_name () const
 365 {
 366   return scm_is_pair (accepts_list_)
 367     ? scm_car (accepts_list_)
 368     : SCM_EOL;
 369 }
 370
 371 bool
 372 Context::is_bottom_context () const
 373 {
 374   return !scm_is_symbol (default_child_context_name ());
 375 }
 376
 377 Context *
 378 Context::get_default_interpreter ()
 379 {
 380   if (!is_bottom_context ())
 381     {
 382       SCM nm = default_child_context_name ();
 383       SCM st = find_context_def (get_output_def (), nm);
 384
 385       string name = ly_symbol2string (nm);
 386       Context_def *t = unsmob_context_def (st);
 387       if (!t)
 388         {
 389           warning (_f ("cannot find or create: `%s'", name.c_str ()));
 390           t = unsmob_context_def (this->definition_);
 391         }
 392
 393       Context *tg = create_context (t, "", SCM_EOL);
 394       return tg->get_default_interpreter ();
 395     }
 396   return this;
 397 }
 398
 399 /*
 400   PROPERTIES
 401 */
 402 Context *
 403 Context::where_defined (SCM sym, SCM *value) const
 404 {
 405 #ifndef NDEBUG
 406   if (profile_property_accesses)
 407     note_property_access (&context_property_lookup_table, sym);
 408 #endif
 409
 410   if (properties_dict ()->try_retrieve (sym, value))
 411     return (Context *)this;
 412
 413   return (daddy_context_) ? daddy_context_->where_defined (sym, value) : 0;
 414 }
 415
 416 /*
 417   return SCM_EOL when not found.
 418 */
 419 SCM
 420 Context::internal_get_property (SCM sym) const
 421 {
 422 #ifndef NDEBUG
 423   if (profile_property_accesses)
 424     note_property_access (&context_property_lookup_table, sym);
 425 #endif
 426
 427   SCM val = SCM_EOL;
 428   if (properties_dict ()->try_retrieve (sym, &val))
 429     return val;
 430
 431   if (daddy_context_)
 432     return daddy_context_->internal_get_property (sym);
 433
 434   return val;
 435 }
 436
 437 /*
 438 Called by the send_stream_event macro. props is a 0-terminated array of
 439 properties and corresponding values, interleaved. This method should not
 440 be called from any other place than the send_stream_event macro.
 441 */
 442 void
 443 Context::internal_send_stream_event (SCM type, Input *origin, SCM props[])
 444 {
 445   Stream_event *e = new Stream_event (type, origin);
 446   for (int i = 0; props[i]; i += 2)
 447     {
 448       e->set_property (props[i], props[i+1]);
 449     }
 450   event_source_->broadcast (e);
 451   e->unprotect ();
 452 }
 453
 454 bool
 455 Context::is_alias (SCM sym) const
 456 {
 457   if (sym == ly_symbol2scm ("Bottom")
 458       && !scm_is_pair (accepts_list_))
 459     return true;
 460   if (sym == unsmob_context_def (definition_)->get_context_name ())
 461     return true;
 462
 463   return scm_c_memq (sym, aliases_) != SCM_BOOL_F;
 464 }
 465
 466 void
 467 Context::add_alias (SCM sym)
 468 {
 469   aliases_ = scm_cons (sym, aliases_);
 470 }
 471
 472 /* we don't (yet) instrument context properties */
 473 void
 474 Context::instrumented_set_property (SCM sym, SCM val, const char*, int, const char*)
 475 {
 476   internal_set_property (sym, val);
 477 }
 478
 479 void
 480 Context::internal_set_property (SCM sym, SCM val)
 481 {
 482   if (do_internal_type_checking_global)
 483     assert (type_check_assignment (sym, val, ly_symbol2scm ("translation-type?")));
 484
 485   properties_dict ()->set (sym, val);
 486 }
 487
 488 /*
 489   TODO: look up to check whether we have inherited var?
 490 */
 491 void
 492 Context::unset_property (SCM sym)
 493 {
 494   properties_dict ()->remove (sym);
 495 }
 496
 497 IMPLEMENT_LISTENER (Context, change_parent);
 498 void
 499 Context::change_parent (SCM sev)
 500 {
 501   Stream_event *ev = unsmob_stream_event (sev);
 502   Context *to = unsmob_context (ev->get_property ("context"));
 503
 504   disconnect_from_parent ();
 505   to->add_context (this);
 506 }
 507
 508 /*
 509   Die. The next GC sweep should take care of the actual death.
 510  */
 511 IMPLEMENT_LISTENER (Context, remove_context);
 512 void
 513 Context::remove_context (SCM)
 514 {
 515   /* ugh, the translator group should listen to RemoveContext events by itself */
 516   Translator_group *impl = implementation ();
 517   if (impl)
 518     impl->disconnect_from_context ();
 519   disconnect_from_parent ();
 520 }
 521
 522 void
 523 Context::disconnect_from_parent ()
 524 {
 525   daddy_context_->events_below_->unregister_as_listener (this->events_below_);
 526   daddy_context_->context_list_ = scm_delq_x (this->self_scm (), daddy_context_->context_list_);
 527   daddy_context_ = 0;
 528 }
 529
 530 /*
 531   ID == "" means accept any ID.
 532 */
 533 Context *
 534 find_context_below (Context *where,
 535                     SCM type, string id)
 536 {
 537   if (where->is_alias (type))
 538     {
 539       if (id == "" || where->id_string () == id)
 540         return where;
 541     }
 542
 543   Context *found = 0;
 544   for (SCM s = where->children_contexts ();
 545        !found && scm_is_pair (s); s = scm_cdr (s))
 546     {
 547       Context *tr = unsmob_context (scm_car (s));
 548
 549       found = find_context_below (tr, type, id);
 550     }
 551
 552   return found;
 553 }
 554
 555 SCM
 556 Context::properties_as_alist () const
 557 {
 558   return properties_dict ()->to_alist ();
 559 }
 560
 561 SCM
 562 Context::context_name_symbol () const
 563 {
 564   Context_def *td = unsmob_context_def (definition_);
 565   return td->get_context_name ();
 566 }
 567
 568 string
 569 Context::context_name () const
 570 {
 571   return ly_symbol2string (context_name_symbol ());
 572 }
 573
 574 Context *
 575 Context::get_score_context () const
 576 {
 577   if (daddy_context_)
 578     return daddy_context_->get_score_context ();
 579   else
 580     return 0;
 581 }
 582
 583 Output_def *
 584 Context::get_output_def () const
 585 {
 586   return daddy_context_ ? daddy_context_->get_output_def () : 0;
 587 }
 588
 589 Context::~Context ()
 590 {
 591 }
 592
 593 Moment
 594 Context::now_mom () const
 595 {
 596   Context const *p = this;
 597   while (p->daddy_context_)
 598     p = p->daddy_context_;
 599
 600   return p->now_mom ();
 601 }
 602
 603 int
 604 Context::print_smob (SCM s, SCM port, scm_print_state *)
 605 {
 606   Context *sc = (Context *) SCM_CELL_WORD_1 (s);
 607
 608   scm_puts ("#<", port);
 609   scm_puts (sc->class_name (), port);
 610   if (Context_def *d = unsmob_context_def (sc->definition_))
 611     {
 612       scm_puts (" ", port);
 613       scm_display (d->get_context_name (), port);
 614     }
 615
 616   if (!sc->id_string_.empty ())
 617     {
 618       scm_puts ("=", port);
 619       scm_puts (sc->id_string_.c_str (), port);
 620     }
 621
 622   scm_puts (" ", port);
 623
 624   scm_display (sc->context_list_, port);
 625   scm_puts (" >", port);
 626
 627   return 1;
 628 }
 629
 630 SCM
 631 Context::mark_smob (SCM sm)
 632 {
 633   Context *me = (Context *) SCM_CELL_WORD_1 (sm);
 634
 635   scm_gc_mark (me->context_list_);
 636   scm_gc_mark (me->aliases_);
 637   scm_gc_mark (me->definition_);
 638   scm_gc_mark (me->definition_mods_);
 639   scm_gc_mark (me->properties_scm_);
 640   scm_gc_mark (me->accepts_list_);
 641
 642   if (me->implementation_)
 643     scm_gc_mark (me->implementation_->self_scm ());
 644
 645   if (me->event_source_)
 646     scm_gc_mark (me->event_source_->self_scm ());
 647
 648   if (me->events_below_)
 649     scm_gc_mark (me->events_below_->self_scm ());
 650
 651   return me->properties_scm_;
 652 }
 653
 654 IMPLEMENT_SMOBS (Context);
 655 IMPLEMENT_DEFAULT_EQUAL_P (Context);
 656 IMPLEMENT_TYPE_P (Context, "ly:context?");
 657
 658 Global_context *
 659 Context::get_global_context () const
 660 {
 661   if (dynamic_cast<Global_context *> ((Context *) this))
 662     return dynamic_cast<Global_context *> ((Context *) this);
 663
 664   if (daddy_context_)
 665     return daddy_context_->get_global_context ();
 666
 667   programming_error ("no Global context");
 668   return 0;
 669 }
 670
 671 Context *
 672 Context::get_parent_context () const
 673 {
 674   return daddy_context_;
 675 }
 676
 677 /*
 678   Ugh. Where to put this?
 679 */
 680 Rational
 681 measure_length (Context const *context)
 682 {
 683   SCM l = context->get_property ("measureLength");
 684   Rational length (1);
 685   if (unsmob_moment (l))
 686     length = unsmob_moment (l)->main_part_;
 687   return length;
 688 }
 689
 690 Moment
 691 measure_position (Context const *context)
 692 {
 693   SCM sm = context->get_property ("measurePosition");
 694
 695   Moment m = 0;
 696   if (unsmob_moment (sm))
 697     {
 698       m = *unsmob_moment (sm);
 699
 700       if (m.main_part_ < Rational (0))
 701         {
 702           Rational length (measure_length (context));
 703           while (m.main_part_ < Rational (0))
 704             m.main_part_ += length;
 705         }
 706     }
 707
 708   return m;
 709 }
 710
 711 /* Finds the measure position after a note of length DUR that
 712    begins at the current measure position. */
 713 Moment
 714 measure_position (Context const *context, Duration const *dur)
 715 {
 716   Moment pos = measure_position (context);
 717   Rational dur_length = dur ? dur->get_length () : Rational (0);
 718
 719   Moment end_pos = pos.grace_part_ < Rational(0)
 720     ? Moment(pos.main_part_, pos.grace_part_ + dur_length)
 721     : Moment(pos.main_part_ + dur_length, 0);
 722
 723   return end_pos;
 724 }
 725
 726 int
 727 measure_number (Context const *context)
 728 {
 729   SCM barnum = context->get_property ("internalBarNumber");
 730   SCM smp = context->get_property ("measurePosition");
 731
 732   int bn = robust_scm2int (barnum, 0);
 733   Moment mp = robust_scm2moment (smp, Moment (0));
 734   if (mp.main_part_ < Rational (0))
 735     bn--;
 736
 737   return bn;
 738 }
 739
 740
 741 void
 742 set_context_property_on_children (Context *trans, SCM sym, SCM val)
 743 {
 744   trans->set_property (sym, ly_deep_copy (val));
 745   for (SCM p = trans->children_contexts (); scm_is_pair (p); p = scm_cdr (p))
 746     {
 747       Context *trg = unsmob_context (scm_car (p));
 748       set_context_property_on_children (trg, sym, ly_deep_copy (val));
 749     }
 750 }
 751
 752 bool
 753 melisma_busy (Context *tr)
 754 {
 755   SCM melisma_properties = tr->get_property ("melismaBusyProperties");
 756   bool busy = false;
 757
 758   for (; !busy && scm_is_pair (melisma_properties);
 759        melisma_properties = scm_cdr (melisma_properties))
 760     busy = busy || to_boolean (tr->internal_get_property (scm_car (melisma_properties)));
 761
 762   return busy;
 763 }