2 scheme-engraver.cc -- implement Scheme_engraver
4 source file of the GNU LilyPond music typesetter
6 Copyright (c) 2009--2015 Han-Wen Nienhuys <hanwen@lilypond.org>
8 LilyPond is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
13 LilyPond is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
22 #include "scheme-engraver.hh"
26 #include "translator.icc"
28 #include "scm-hash.hh"
30 Preinit_Scheme_engraver::Preinit_Scheme_engraver ()
32 initialize_function_ = SCM_EOL;
33 finalize_function_ = SCM_EOL;
35 interface_acknowledger_hash_.set (SCM_EOL, SCM_EOL);
37 per_instance_listeners_ = SCM_EOL;
38 for (int i = 0; i < TRANSLATOR_METHOD_PRECOMPUTE_COUNT; i++)
39 precomputable_methods_[i] = SCM_UNDEFINED;
42 Scheme_engraver::~Scheme_engraver ()
46 // Extracts the value if callable, if not return SCM_UNDEFINED;
48 callable (SCM symbol, SCM defn)
50 SCM val = ly_assoc_get (symbol, defn, SCM_BOOL_F);
51 return ly_is_procedure (val) ? val : SCM_UNDEFINED;
55 Scheme_engraver::must_be_last () const
61 Scheme_engraver::fetch_precomputable_methods (SCM ptrs[])
63 for (int i = 0; i < TRANSLATOR_METHOD_PRECOMPUTE_COUNT; i++)
64 ptrs[i] = precomputable_methods_[i];
67 Scheme_engraver::Scheme_engraver (SCM definition)
69 precomputable_methods_[START_TRANSLATION_TIMESTEP]
70 = callable (ly_symbol2scm ("start-translation-timestep"), definition);
71 precomputable_methods_[STOP_TRANSLATION_TIMESTEP]
72 = callable (ly_symbol2scm ("stop-translation-timestep"), definition);
73 precomputable_methods_[PROCESS_MUSIC]
74 = callable (ly_symbol2scm ("process-music"), definition);
75 precomputable_methods_[PROCESS_ACKNOWLEDGED]
76 = callable (ly_symbol2scm ("process-acknowledged"), definition);
77 initialize_function_ = callable (ly_symbol2scm ("initialize"), definition);
78 finalize_function_ = callable (ly_symbol2scm ("finalize"), definition);
80 SCM p = ly_assoc_get (ly_symbol2scm ("listeners"), definition, SCM_EOL);
81 SCM listeners = SCM_EOL;
83 must_be_last_ = to_boolean (ly_assoc_get (ly_symbol2scm ("must-be-last"),
87 for (; scm_is_pair (p); p = scm_cdr (p))
89 SCM event_class = scm_caar (p);
90 SCM proc = scm_cdar (p);
92 if (!(ly_is_procedure (proc) && ly_is_symbol (event_class)))
95 // We should check the arity of the function?
97 // Record for later lookup.
98 listeners = scm_acons (event_class, proc, listeners);
102 init_acknowledgers (ly_assoc_get (ly_symbol2scm ("acknowledgers"),
103 definition, SCM_EOL));
105 init_acknowledgers (ly_assoc_get (ly_symbol2scm ("end-acknowledgers"),
106 definition, SCM_EOL));
108 per_instance_listeners_ = listeners;
109 interface_acknowledger_hash_.set (hash1, hash2);
111 // It's not defined whether Scheme_engraver::derived_mark is already
112 // active while the construction is underway, so we make sure we
113 // keep a version of everything on the stack that is not still
114 // covered by `definition'.
116 scm_remember_upto_here_2 (definition, listeners);
117 scm_remember_upto_here_2 (hash1, hash2);
119 // TODO: hook up description, props read/written, grobs created
120 // etc. to provide automatic documentation.
124 Scheme_engraver::init_acknowledgers (SCM alist)
126 SCM hash = Scheme_hash_table::make_smob ();
127 for (SCM p = alist; scm_is_pair (p); p = scm_cdr (p))
129 SCM iface = scm_caar (p);
130 SCM proc = scm_cdar (p);
132 if (!(ly_is_procedure (proc) && ly_is_symbol (iface)))
135 unsmob<Scheme_hash_table>(hash)->set (iface, proc);
141 Scheme_engraver::get_listener_list () const
143 return per_instance_listeners_;
147 Scheme_engraver::initialize ()
149 if (!SCM_UNBNDP (initialize_function_))
150 scm_call_1 (initialize_function_, self_scm ());
154 Scheme_engraver::finalize ()
156 if (!SCM_UNBNDP (finalize_function_))
157 scm_call_1 (finalize_function_, self_scm ());
161 Scheme_engraver::derived_mark () const
163 for (int i = 0; i < TRANSLATOR_METHOD_PRECOMPUTE_COUNT; i++)
164 scm_gc_mark (precomputable_methods_[i]);
166 scm_gc_mark (initialize_function_);
167 scm_gc_mark (finalize_function_);
168 scm_gc_mark (per_instance_listeners_);
169 scm_gc_mark (interface_acknowledger_hash_[START]);
170 scm_gc_mark (interface_acknowledger_hash_[STOP]);