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