lily/context.cc

   1 /*
   2   context.cc -- implement Context
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2004--2007 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   (void) src;
  52   assert (false);
  53 }
  54
  55 Scheme_hash_table *
  56 Context::properties_dict () const
  57 {
  58   return Scheme_hash_table::unsmob (properties_scm_);
  59 }
  60
  61 void
  62 Context::add_context (Context *child)
  63 {
  64   context_list_ = ly_append2 (context_list_,
  65                               scm_cons (child->self_scm (), SCM_EOL));
  66
  67   child->daddy_context_ = this;
  68   this->events_below_->register_as_listener (child->events_below_);
  69 }
  70
  71
  72 Context::Context ()
  73 {
  74   daddy_context_ = 0;
  75   aliases_ = SCM_EOL;
  76   iterator_count_ = 0;
  77   implementation_ = 0;
  78   properties_scm_ = SCM_EOL;
  79   accepts_list_ = SCM_EOL;
  80   context_list_ = SCM_EOL;
  81   definition_ = SCM_EOL;
  82   definition_mods_ = SCM_EOL;
  83   event_source_ = 0;
  84   events_below_ = 0;
  85
  86   smobify_self ();
  87
  88   Scheme_hash_table *tab = new Scheme_hash_table;
  89   properties_scm_ = tab->unprotect ();
  90   event_source_ = new Dispatcher ();
  91   event_source_->unprotect ();
  92   events_below_ = new Dispatcher ();
  93   events_below_->unprotect ();
  94 }
  95
  96 /* TODO:  this shares code with find_create_context ().  */
  97 Context *
  98 Context::create_unique_context (SCM name, string id, SCM operations)
  99 {
 100   /*
 101     Don't create multiple score contexts.
 102   */
 103   Global_context *gthis = dynamic_cast<Global_context *> (this);
 104   if (gthis && gthis->get_score_context ())
 105     return gthis->get_score_context ()->create_unique_context (name, id, operations);
 106
 107   /*
 108     TODO: use accepts_list_.
 109   */
 110   vector<Context_def*> path
 111     = unsmob_context_def (definition_)->path_to_acceptable_context (name, get_output_def ());
 112
 113   if (path.size ())
 114     {
 115       Context *current = this;
 116
 117       // start at 1.  The first one (index 0) will be us.
 118       for (vsize i = 0; i < path.size (); i++)
 119         {
 120           SCM ops = SCM_EOL;
 121           string id_str = "\\new";
 122           if (i == path.size () - 1)
 123             {
 124               ops = operations;
 125               id_str = id;
 126             }
 127           current = current->create_context (path[i],
 128                                              id_str,
 129                                              ops);
 130         }
 131
 132       return current;
 133     }
 134
 135   /*
 136     Don't go up to Global_context, because global goes down to the
 137     Score context
 138   */
 139   Context *ret = 0;
 140   if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
 141     ret = daddy_context_->create_unique_context (name, id, operations);
 142   else
 143     {
 144       warning (_f ("cannot find or create new `%s'",
 145                    ly_symbol2string (name).c_str ()));
 146       ret = 0;
 147     }
 148   return ret;
 149 }
 150
 151 Context *
 152 Context::find_create_context (SCM n, string id, SCM operations)
 153 {
 154   /*
 155     Don't create multiple score contexts.
 156   */
 157   Global_context *gthis = dynamic_cast<Global_context *> (this);
 158   if (gthis && gthis->get_score_context ())
 159     return gthis->get_score_context ()->find_create_context (n, id, operations);
 160
 161   if (Context *existing = find_context_below (this, n, id))
 162     return existing;
 163
 164   if (n == ly_symbol2scm ("Bottom"))
 165     {
 166       Context *tg = get_default_interpreter ();
 167       return tg;
 168     }
 169
 170   /*
 171     TODO: use accepts_list_.
 172   */
 173   vector<Context_def*> path
 174     = unsmob_context_def (definition_)->path_to_acceptable_context (n, get_output_def ());
 175
 176   if (path.size ())
 177     {
 178       Context *current = this;
 179
 180       // start at 1.  The first one (index 0) will be us.
 181       for (vsize i = 0; i < path.size (); i++)
 182         {
 183           SCM ops = (i == path.size () -1) ? operations : SCM_EOL;
 184
 185           string this_id = "";
 186           if (i == path.size () -1)
 187             this_id = id;
 188
 189           current = current->create_context (path[i],
 190                                              this_id,
 191                                              ops);
 192         }
 193
 194       return current;
 195     }
 196
 197   /*
 198     Don't go up to Global_context, because global goes down to the
 199     Score context
 200   */
 201   Context *ret = 0;
 202   if (daddy_context_ && !dynamic_cast<Global_context *> (daddy_context_))
 203     ret = daddy_context_->find_create_context (n, id, operations);
 204   else
 205     {
 206       warning (_f ("cannot find or create `%s' called `%s'",
 207                    ly_symbol2string (n).c_str (), id));
 208       ret = 0;
 209     }
 210   return ret;
 211 }
 212
 213 IMPLEMENT_LISTENER (Context, acknowledge_infant);
 214 void
 215 Context::acknowledge_infant (SCM sev)
 216 {
 217   infant_event_ = unsmob_stream_event (sev);
 218 }
 219
 220 IMPLEMENT_LISTENER (Context, set_property_from_event);
 221 void
 222 Context::set_property_from_event (SCM sev)
 223 {
 224   Stream_event *ev = unsmob_stream_event (sev);
 225
 226   SCM sym = ev->get_property ("symbol");
 227   if (scm_is_symbol (sym))
 228     {
 229       SCM val = ev->get_property ("value");
 230       bool ok = true;
 231       if (val != SCM_EOL)
 232         ok = type_check_assignment (sym, val, ly_symbol2scm ("translation-type?"));
 233       if (ok)
 234         set_property (sym, val);
 235     }
 236 }
 237
 238 IMPLEMENT_LISTENER (Context, unset_property_from_event);
 239 void
 240 Context::unset_property_from_event (SCM sev)
 241 {
 242   Stream_event *ev = unsmob_stream_event (sev);
 243
 244   SCM sym = ev->get_property ("symbol");
 245   type_check_assignment (sym, SCM_EOL, ly_symbol2scm ("translation-type?"));
 246   unset_property (sym);
 247 }
 248
 249 /*
 250   Creates a new context from a CreateContext event, and sends an
 251   AnnounceNewContext event to this context.
 252 */
 253 IMPLEMENT_LISTENER (Context, create_context_from_event);
 254 void
 255 Context::create_context_from_event (SCM sev)
 256 {
 257   Stream_event *ev = unsmob_stream_event (sev);
 258
 259   string id = ly_scm2string (ev->get_property ("id"));
 260   SCM ops = ev->get_property ("ops");
 261   SCM type_scm = ev->get_property ("type");
 262   string type = ly_symbol2string (type_scm);
 263
 264   vector<Context_def*> path
 265     = unsmob_context_def (definition_)->path_to_acceptable_context (type_scm, get_output_def ());
 266   if (path.size () != 1)
 267     {
 268       programming_error (_f ("Invalid CreateContext event: Cannot create %s context", type.c_str ()));
 269       return;
 270     }
 271   Context_def *cdef = path[0];
 272
 273   Context *new_context = cdef->instantiate (ops);
 274
 275   new_context->id_string_ = id;
 276
 277   /* Register various listeners:
 278       - Make the new context hear events that universally affect contexts
 279       - connect events_below etc. properly */
 280   /* We want to be the first ones to hear our own events. Therefore, wait
 281      before registering events_below_ */
 282   new_context->event_source ()->
 283     add_listener (GET_LISTENER (new_context->create_context_from_event),
 284                   ly_symbol2scm ("CreateContext"));
 285   new_context->event_source ()->
 286     add_listener (GET_LISTENER (new_context->remove_context),
 287                   ly_symbol2scm ("RemoveContext"));
 288   new_context->event_source ()->
 289     add_listener (GET_LISTENER (new_context->change_parent),
 290                   ly_symbol2scm ("ChangeParent"));
 291   new_context->event_source ()->
 292     add_listener (GET_LISTENER (new_context->set_property_from_event),
 293                   ly_symbol2scm ("SetProperty"));
 294   new_context->event_source ()->
 295     add_listener (GET_LISTENER (new_context->unset_property_from_event),
 296                   ly_symbol2scm ("UnsetProperty"));
 297
 298   new_context->events_below_->register_as_listener (new_context->event_source_);
 299   this->add_context (new_context);
 300
 301   new_context->unprotect ();
 302
 303   Context_def *td = unsmob_context_def (new_context->definition_);
 304
 305   /* This cannot move before add_context (), because \override
 306      operations require that we are in the hierarchy.  */
 307   td->apply_default_property_operations (new_context);
 308   apply_property_operations (new_context, ops);
 309
 310   send_stream_event (this, "AnnounceNewContext", 0,
 311                      ly_symbol2scm ("context"), new_context->self_scm (),
 312                      ly_symbol2scm ("creator"), sev);
 313 }
 314
 315 Context *
 316 Context::create_context (Context_def *cdef,
 317                          string id,
 318                          SCM ops)
 319 {
 320   infant_event_ = 0;
 321   /* TODO: This is fairly misplaced. We can fix this when we have taken out all
 322      iterator specific stuff from the Context class */
 323   event_source_->
 324     add_listener (GET_LISTENER (acknowledge_infant),
 325                   ly_symbol2scm ("AnnounceNewContext"));
 326   /* The CreateContext creates a new context, and sends an announcement of the
 327      new context through another event. That event will be stored in
 328      infant_event_ to create a return value. */
 329   send_stream_event (this, "CreateContext", 0,
 330                      ly_symbol2scm ("ops"), ops,
 331                      ly_symbol2scm ("type"), cdef->get_context_name (),
 332                      ly_symbol2scm ("id"), ly_string2scm (id));
 333   event_source_->
 334     remove_listener (GET_LISTENER (acknowledge_infant),
 335                      ly_symbol2scm ("AnnounceNewContext"));
 336
 337   assert (infant_event_);
 338   SCM infant_scm = infant_event_->get_property ("context");
 339   Context *infant = unsmob_context (infant_scm);
 340
 341   if (!infant || infant->get_parent_context () != this)
 342     {
 343       programming_error ("create_context: can't locate newly created context");
 344       return 0;
 345     }
 346
 347   return infant;
 348 }
 349
 350 /*
 351   Default child context as a SCM string, or something else if there is
 352   none.
 353 */
 354 SCM
 355 Context::default_child_context_name () const
 356 {
 357   return scm_is_pair (accepts_list_)
 358     ? scm_car (accepts_list_)
 359     : SCM_EOL;
 360 }
 361
 362 bool
 363 Context::is_bottom_context () const
 364 {
 365   return !scm_is_symbol (default_child_context_name ());
 366 }
 367
 368 Context *
 369 Context::get_default_interpreter ()
 370 {
 371   if (!is_bottom_context ())
 372     {
 373       SCM nm = default_child_context_name ();
 374       SCM st = find_context_def (get_output_def (), nm);
 375
 376       string name = ly_symbol2string (nm);
 377       Context_def *t = unsmob_context_def (st);
 378       if (!t)
 379         {
 380           warning (_f ("cannot find or create: `%s'", name.c_str ()));
 381           t = unsmob_context_def (this->definition_);
 382         }
 383
 384       Context *tg = create_context (t, "", SCM_EOL);
 385       return tg->get_default_interpreter ();
 386     }
 387   return this;
 388 }
 389
 390 /*
 391   PROPERTIES
 392 */
 393 Context *
 394 Context::where_defined (SCM sym, SCM *value) const
 395 {
 396 #ifndef NDEBUG
 397   if (profile_property_accesses)
 398     note_property_access (&context_property_lookup_table, sym);
 399 #endif
 400
 401   if (properties_dict ()->try_retrieve (sym, value))
 402     return (Context *)this;
 403
 404   return (daddy_context_) ? daddy_context_->where_defined (sym, value) : 0;
 405 }
 406
 407 /*
 408   return SCM_EOL when not found.
 409 */
 410 SCM
 411 Context::internal_get_property (SCM sym) const
 412 {
 413 #ifndef NDEBUG
 414   if (profile_property_accesses)
 415     note_property_access (&context_property_lookup_table, sym);
 416 #endif
 417
 418   SCM val = SCM_EOL;
 419   if (properties_dict ()->try_retrieve (sym, &val))
 420     return val;
 421
 422   if (daddy_context_)
 423     return daddy_context_->internal_get_property (sym);
 424
 425   return val;
 426 }
 427
 428 /*
 429 Called by the send_stream_event macro. props is a 0-terminated array of
 430 properties and corresponding values, interleaved. This method should not
 431 be called from any other place than the send_stream_event macro.
 432 */
 433 void
 434 Context::internal_send_stream_event (SCM type, Input *origin, SCM props[])
 435 {
 436   Stream_event *e = new Stream_event (type, origin);
 437   for (int i = 0; props[i]; i += 2)
 438     {
 439       e->set_property (props[i], props[i+1]);
 440     }
 441   event_source_->broadcast (e);
 442   e->unprotect ();
 443 }
 444
 445 bool
 446 Context::is_alias (SCM sym) const
 447 {
 448   if (sym == ly_symbol2scm ("Bottom")
 449       && !scm_is_pair (accepts_list_))
 450     return true;
 451   if (sym == unsmob_context_def (definition_)->get_context_name ())
 452     return true;
 453
 454   return scm_c_memq (sym, aliases_) != SCM_BOOL_F;
 455 }
 456
 457 void
 458 Context::add_alias (SCM sym)
 459 {
 460   aliases_ = scm_cons (sym, aliases_);
 461 }
 462
 463 /* we don't (yet) instrument context properties */
 464 void
 465 Context::instrumented_set_property (SCM sym, SCM val, const char*, int, const char*)
 466 {
 467   internal_set_property (sym, val);
 468 }
 469
 470 void
 471 Context::internal_set_property (SCM sym, SCM val)
 472 {
 473   if (do_internal_type_checking_global)
 474     assert (type_check_assignment (sym, val, ly_symbol2scm ("translation-type?")));
 475
 476   properties_dict ()->set (sym, val);
 477 }
 478
 479 /*
 480   TODO: look up to check whether we have inherited var?
 481 */
 482 void
 483 Context::unset_property (SCM sym)
 484 {
 485   properties_dict ()->remove (sym);
 486 }
 487
 488 IMPLEMENT_LISTENER (Context, change_parent);
 489 void
 490 Context::change_parent (SCM sev)
 491 {
 492   Stream_event *ev = unsmob_stream_event (sev);
 493   Context *to = unsmob_context (ev->get_property ("context"));
 494
 495   disconnect_from_parent ();
 496   to->add_context (this);
 497 }
 498
 499 /*
 500   Die. The next GC sweep should take care of the actual death.
 501  */
 502 IMPLEMENT_LISTENER (Context, remove_context);
 503 void
 504 Context::remove_context (SCM)
 505 {
 506   /* ugh, the translator group should listen to RemoveContext events by itself */
 507   Translator_group *impl = implementation ();
 508   if (impl)
 509     impl->disconnect_from_context ();
 510   disconnect_from_parent ();
 511 }
 512
 513 void
 514 Context::disconnect_from_parent ()
 515 {
 516   daddy_context_->events_below_->unregister_as_listener (this->events_below_);
 517   daddy_context_->context_list_ = scm_delq_x (this->self_scm (), daddy_context_->context_list_);
 518   daddy_context_ = 0;
 519 }
 520
 521 /*
 522   ID == "" means accept any ID.
 523 */
 524 Context *
 525 find_context_below (Context *where,
 526                     SCM type, string id)
 527 {
 528   if (where->is_alias (type))
 529     {
 530       if (id == "" || where->id_string () == id)
 531         return where;
 532     }
 533
 534   Context *found = 0;
 535   for (SCM s = where->children_contexts ();
 536        !found && scm_is_pair (s); s = scm_cdr (s))
 537     {
 538       Context *tr = unsmob_context (scm_car (s));
 539
 540       found = find_context_below (tr, type, id);
 541     }
 542
 543   return found;
 544 }
 545
 546 SCM
 547 Context::properties_as_alist () const
 548 {
 549   return properties_dict ()->to_alist ();
 550 }
 551
 552 SCM
 553 Context::context_name_symbol () const
 554 {
 555   Context_def *td = unsmob_context_def (definition_);
 556   return td->get_context_name ();
 557 }
 558
 559 string
 560 Context::context_name () const
 561 {
 562   return ly_symbol2string (context_name_symbol ());
 563 }
 564
 565 Context *
 566 Context::get_score_context () const
 567 {
 568   if (daddy_context_)
 569     return daddy_context_->get_score_context ();
 570   else
 571     return 0;
 572 }
 573
 574 Output_def *
 575 Context::get_output_def () const
 576 {
 577   return daddy_context_ ? daddy_context_->get_output_def () : 0;
 578 }
 579
 580 Context::~Context ()
 581 {
 582 }
 583
 584 Moment
 585 Context::now_mom () const
 586 {
 587   Context const *p = this;
 588   while (p->daddy_context_)
 589     p = p->daddy_context_;
 590
 591   return p->now_mom ();
 592 }
 593
 594 int
 595 Context::print_smob (SCM s, SCM port, scm_print_state *)
 596 {
 597   Context *sc = (Context *) SCM_CELL_WORD_1 (s);
 598
 599   scm_puts ("#<", port);
 600   scm_puts (sc->class_name (), port);
 601   if (Context_def *d = unsmob_context_def (sc->definition_))
 602     {
 603       scm_puts (" ", port);
 604       scm_display (d->get_context_name (), port);
 605     }
 606
 607   if (!sc->id_string_.empty ())
 608     {
 609       scm_puts ("=", port);
 610       scm_puts (sc->id_string_.c_str (), port);
 611     }
 612
 613   scm_puts (" ", port);
 614
 615   scm_display (sc->context_list_, port);
 616   scm_puts (" >", port);
 617
 618   return 1;
 619 }
 620
 621 SCM
 622 Context::mark_smob (SCM sm)
 623 {
 624   Context *me = (Context *) SCM_CELL_WORD_1 (sm);
 625
 626   scm_gc_mark (me->context_list_);
 627   scm_gc_mark (me->aliases_);
 628   scm_gc_mark (me->definition_);
 629   scm_gc_mark (me->definition_mods_);
 630   scm_gc_mark (me->properties_scm_);
 631   scm_gc_mark (me->accepts_list_);
 632
 633   if (me->implementation_)
 634     scm_gc_mark (me->implementation_->self_scm ());
 635
 636   if (me->event_source_)
 637     scm_gc_mark (me->event_source_->self_scm ());
 638
 639   if (me->events_below_)
 640     scm_gc_mark (me->events_below_->self_scm ());
 641
 642   return me->properties_scm_;
 643 }
 644
 645 IMPLEMENT_SMOBS (Context);
 646 IMPLEMENT_DEFAULT_EQUAL_P (Context);
 647 IMPLEMENT_TYPE_P (Context, "ly:context?");
 648
 649 Global_context *
 650 Context::get_global_context () const
 651 {
 652   if (dynamic_cast<Global_context *> ((Context *) this))
 653     return dynamic_cast<Global_context *> ((Context *) this);
 654
 655   if (daddy_context_)
 656     return daddy_context_->get_global_context ();
 657
 658   programming_error ("no Global context");
 659   return 0;
 660 }
 661
 662 Context *
 663 Context::get_parent_context () const
 664 {
 665   return daddy_context_;
 666 }
 667
 668 /*
 669   Ugh. Where to put this?
 670 */
 671 Rational
 672 measure_length (Context const *context)
 673 {
 674   SCM l = context->get_property ("measureLength");
 675   Rational length (1);
 676   if (unsmob_moment (l))
 677     length = unsmob_moment (l)->main_part_;
 678   return length;
 679 }
 680
 681 Moment
 682 measure_position (Context const *context)
 683 {
 684   SCM sm = context->get_property ("measurePosition");
 685
 686   Moment m = 0;
 687   if (unsmob_moment (sm))
 688     {
 689       m = *unsmob_moment (sm);
 690
 691       if (m.main_part_ < Rational (0))
 692         {
 693           Rational length (measure_length (context));
 694           while (m.main_part_ < Rational (0))
 695             m.main_part_ += length;
 696         }
 697     }
 698
 699   return m;
 700 }
 701
 702
 703 void
 704 set_context_property_on_children (Context *trans, SCM sym, SCM val)
 705 {
 706   trans->set_property (sym, ly_deep_copy (val));
 707   for (SCM p = trans->children_contexts (); scm_is_pair (p); p = scm_cdr (p))
 708     {
 709       Context *trg = unsmob_context (scm_car (p));
 710       set_context_property_on_children (trg, sym, ly_deep_copy (val));
 711     }
 712 }
 713
 714 bool
 715 melisma_busy (Context *tr)
 716 {
 717   SCM melisma_properties = tr->get_property ("melismaBusyProperties");
 718   bool busy = false;
 719
 720   for (; !busy && scm_is_pair (melisma_properties);
 721        melisma_properties = scm_cdr (melisma_properties))
 722     busy = busy || to_boolean (tr->internal_get_property (scm_car (melisma_properties)));
 723
 724   return busy;
 725 }