lily/translator-group.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>,
   5                  Erik Sandberg <mandolaerik@gmail.com>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "translator-group.hh"
  22
  23 #include "context-def.hh"
  24 #include "context.hh"
  25 #include "dispatcher.hh"
  26 #include "engraver-group.hh"
  27 #include "international.hh"
  28 #include "main.hh"
  29 #include "music.hh"
  30 #include "output-def.hh"
  31 #include "performer-group.hh"
  32 #include "scheme-engraver.hh"
  33 #include "scm-hash.hh"
  34 #include "warn.hh"
  35
  36 void
  37 translator_each (SCM list, Translator_method method)
  38 {
  39   for (SCM p = list; scm_is_pair (p); p = scm_cdr (p))
  40     (unsmob_translator (scm_car (p))->*method) ();
  41 }
  42
  43 void
  44 Translator_group::initialize ()
  45 {
  46   precompute_method_bindings ();
  47 }
  48
  49 void
  50 Translator_group::connect_to_context (Context *c)
  51 {
  52   if (context_)
  53     {
  54       programming_error ("translator group is already connected to context "
  55                          +  context_->context_name ());
  56     }
  57
  58   context_ = c;
  59   c->event_source ()->add_listener (GET_LISTENER (create_child_translator),
  60                                     ly_symbol2scm ("AnnounceNewContext"));
  61   for (SCM tr_list = simple_trans_list_; scm_is_pair (tr_list); tr_list = scm_cdr (tr_list))
  62     {
  63       Translator *tr = unsmob_translator (scm_car (tr_list));
  64       tr->connect_to_context (c);
  65     }
  66 }
  67
  68 void
  69 Translator_group::disconnect_from_context ()
  70 {
  71   for (SCM tr_list = simple_trans_list_; scm_is_pair (tr_list); tr_list = scm_cdr (tr_list))
  72     {
  73       Translator *tr = unsmob_translator (scm_car (tr_list));
  74       tr->disconnect_from_context (context_);
  75     }
  76   context_->event_source ()->remove_listener (GET_LISTENER (create_child_translator),
  77                                               ly_symbol2scm ("AnnounceNewContext"));
  78   context_ = 0;
  79   protected_events_ = SCM_EOL;
  80 }
  81
  82 void
  83 Translator_group::finalize ()
  84 {
  85 }
  86
  87 SCM
  88 filter_performers (SCM ell)
  89 {
  90   SCM *tail = &ell;
  91   for (SCM p = ell; scm_is_pair (p); p = scm_cdr (p))
  92     {
  93       if (dynamic_cast<Performer *> (unsmob_translator (scm_car (*tail))))
  94         *tail = scm_cdr (*tail);
  95       else
  96         tail = SCM_CDRLOC (*tail);
  97     }
  98   return ell;
  99 }
 100
 101 SCM
 102 filter_engravers (SCM ell)
 103 {
 104   SCM *tail = &ell;
 105   for (SCM p = ell; scm_is_pair (p); p = scm_cdr (p))
 106     {
 107       if (dynamic_cast<Engraver *> (unsmob_translator (scm_car (*tail))))
 108         *tail = scm_cdr (*tail);
 109       else
 110         tail = SCM_CDRLOC (*tail);
 111     }
 112   return ell;
 113 }
 114
 115 /*
 116   Protects the parameter from being garbage collected. The object is
 117   protected until the next disconnect_from_context call.
 118
 119   Whenever a child translator hears an event, the event is added to
 120   this list. This eliminates the need for derived_mark methods in most
 121   translators; all incoming events are instead protected by the
 122   translator group.
 123
 124   TODO: Should the list also be flushed at the beginning of each new
 125   moment?
 126  */
 127 void
 128 Translator_group::protect_event (SCM ev)
 129 {
 130   protected_events_ = scm_cons (ev, protected_events_);
 131 }
 132
 133 /*
 134   Create a new translator for a newly created child context. Triggered
 135   by AnnounceNewContext events.
 136  */
 137 IMPLEMENT_LISTENER (Translator_group, create_child_translator);
 138 void
 139 Translator_group::create_child_translator (SCM sev)
 140 {
 141   Stream_event *ev = unsmob_stream_event (sev);
 142   // get from AnnounceNewContext
 143   SCM cs = ev->get_property ("context");
 144   Context *new_context = unsmob_context (cs);
 145   Context_def *def = unsmob_context_def (new_context->get_definition ());
 146   SCM ops = new_context->get_definition_mods ();
 147
 148   SCM trans_names = def->get_translator_names (ops);
 149
 150   Translator_group *g = get_translator_group (def->get_translator_group_type ());
 151   SCM trans_list = SCM_EOL;
 152
 153   for (SCM s = trans_names; scm_is_pair (s); s = scm_cdr (s))
 154     {
 155       SCM definition = scm_car (s);
 156       bool is_scheme = false;
 157
 158       Translator *type = 0;
 159       if (ly_is_symbol (definition))
 160         type = get_translator (definition);
 161       else if (ly_is_pair (definition))
 162         {
 163           type = get_translator (ly_symbol2scm ("Scheme_engraver"));
 164           is_scheme = true;
 165         }
 166       else if (ly_is_procedure (definition))
 167         {
 168           // `definition' is a procedure, which takes the context as
 169           // an argument and evaluates to an a-list scheme engraver
 170           // definition.
 171           definition = scm_call_1 (definition, cs);
 172           type = get_translator (ly_symbol2scm ("Scheme_engraver"));
 173           is_scheme = true;
 174         }
 175
 176       if (!type)
 177         warning (_f ("cannot find: `%s'", ly_symbol2string (scm_car (s)).c_str ()));
 178       else
 179         {
 180           Translator *instance = type->clone ();
 181           if (is_scheme)
 182             dynamic_cast<Scheme_engraver *> (instance)->init_from_scheme (definition);
 183
 184           SCM str = instance->self_scm ();
 185
 186           if (instance->must_be_last ())
 187             {
 188               SCM cons = scm_cons (str, SCM_EOL);
 189               if (scm_is_pair (trans_list))
 190                 scm_set_cdr_x (scm_last_pair (trans_list), cons);
 191               else
 192                 trans_list = cons;
 193             }
 194           else
 195             trans_list = scm_cons (str, trans_list);
 196
 197           instance->daddy_context_ = new_context;
 198           instance->unprotect ();
 199         }
 200     }
 201
 202   /* Filter unwanted translator types. Required to make
 203      \with { \consists "..." } work. */
 204   if (dynamic_cast<Engraver_group *> (g))
 205     g->simple_trans_list_ = filter_performers (trans_list);
 206   else if (dynamic_cast<Performer_group *> (g))
 207     g->simple_trans_list_ = filter_engravers (trans_list);
 208
 209   // TODO: scrap Context::implementation
 210   new_context->implementation_ = g;
 211
 212   g->connect_to_context (new_context);
 213   g->unprotect ();
 214
 215   recurse_over_translators (new_context,
 216                             &Translator::initialize,
 217                             &Translator_group::initialize,
 218                             DOWN);
 219 }
 220
 221 SCM
 222 Translator_group::get_simple_trans_list ()
 223 {
 224   return simple_trans_list_;
 225 }
 226
 227 void
 228 precomputed_recurse_over_translators (Context *c, Translator_precompute_index idx, Direction dir)
 229 {
 230   Translator_group *tg
 231     = dynamic_cast<Translator_group *> (c->implementation ());
 232
 233   if (tg && dir == DOWN)
 234     {
 235       tg->precomputed_translator_foreach (idx);
 236       tg->call_precomputed_self_method (idx);
 237     }
 238
 239   for (SCM s = c->children_contexts (); scm_is_pair (s);
 240        s = scm_cdr (s))
 241     precomputed_recurse_over_translators (unsmob_context (scm_car (s)), idx, dir);
 242
 243   if (tg && dir == UP)
 244     {
 245       tg->precomputed_translator_foreach (idx);
 246       tg->call_precomputed_self_method (idx);
 247     }
 248 }
 249
 250 void
 251 recurse_over_translators (Context *c, Translator_method ptr,
 252                           Translator_group_method tg_ptr, Direction dir)
 253 {
 254   Translator_group *tg
 255     = dynamic_cast<Translator_group *> (c->implementation ());
 256
 257   if (tg && dir == DOWN)
 258     {
 259       (tg->*tg_ptr) ();
 260       translator_each (tg->get_simple_trans_list (), ptr);
 261     }
 262
 263   for (SCM s = c->children_contexts (); scm_is_pair (s);
 264        s = scm_cdr (s))
 265     recurse_over_translators (unsmob_context (scm_car (s)), ptr, tg_ptr, dir);
 266
 267   if (tg && dir == UP)
 268     {
 269       translator_each (tg->get_simple_trans_list (),
 270                        ptr);
 271
 272       (tg->*tg_ptr) ();
 273     }
 274 }
 275
 276 Translator_group::Translator_group ()
 277 {
 278   simple_trans_list_ = SCM_EOL;
 279   protected_events_ = SCM_EOL;
 280   context_ = 0;
 281   smobify_self ();
 282 }
 283
 284 void
 285 Translator_group::derived_mark () const
 286 {
 287 }
 288
 289 void
 290 Translator_group::precompute_method_bindings ()
 291 {
 292   for (SCM s = simple_trans_list_; scm_is_pair (s); s = scm_cdr (s))
 293     {
 294       Translator *tr = unsmob_translator (scm_car (s));
 295       Translator_void_method_ptr ptrs[TRANSLATOR_METHOD_PRECOMPUTE_COUNT];
 296       tr->fetch_precomputable_methods (ptrs);
 297
 298       assert (tr);
 299       for (int i = 0; i < TRANSLATOR_METHOD_PRECOMPUTE_COUNT; i++)
 300         {
 301           if (ptrs[i])
 302             precomputed_method_bindings_[i].push_back (Translator_method_binding (tr, ptrs[i]));
 303         }
 304     }
 305
 306   fetch_precomputable_methods (precomputed_self_method_bindings_);
 307 }
 308
 309 void
 310 Translator_group::precomputed_translator_foreach (Translator_precompute_index idx)
 311 {
 312   vector<Translator_method_binding> &bindings (precomputed_method_bindings_[idx]);
 313   for (vsize i = 0; i < bindings.size (); i++)
 314     bindings[i].invoke ();
 315 }
 316
 317 void
 318 Translator_group::fetch_precomputable_methods (Translator_group_void_method ptrs[])
 319 {
 320   for (int i = 0; i < TRANSLATOR_METHOD_PRECOMPUTE_COUNT; i++)
 321     ptrs[i] = 0;
 322 }
 323
 324 void
 325 Translator_group::call_precomputed_self_method (Translator_precompute_index idx)
 326 {
 327   if (precomputed_self_method_bindings_[idx])
 328     (*precomputed_self_method_bindings_[idx]) (this);
 329 }
 330
 331 Translator_group::~Translator_group ()
 332 {
 333 }
 334
 335 #include "ly-smobs.icc"
 336
 337 IMPLEMENT_SMOBS (Translator_group);
 338 IMPLEMENT_DEFAULT_EQUAL_P (Translator_group);
 339 IMPLEMENT_TYPE_P (Translator_group, "ly:translator-group?");
 340
 341 int
 342 Translator_group::print_smob (SCM s, SCM port, scm_print_state *)
 343 {
 344   Translator_group *me = (Translator_group *) SCM_CELL_WORD_1 (s);
 345   scm_puts ("#<Translator_group ", port);
 346   scm_puts (me->class_name (), port);
 347   scm_display (me->simple_trans_list_, port);
 348   scm_puts (" >", port);
 349   return 1;
 350 }
 351
 352 SCM
 353 Translator_group::mark_smob (SCM smob)
 354 {
 355   Translator_group *me = (Translator_group *)SCM_CELL_WORD_1 (smob);
 356
 357   me->derived_mark ();
 358   scm_gc_mark (me->protected_events_);
 359   return me->simple_trans_list_;
 360 }