lily/smobs.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2005--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "smobs.hh"
  21
  22 /*
  23   The CDR contains the actual protected list.
  24  */
  25 static SCM smob_protection_list = SCM_EOL;
  26
  27 void
  28 init_smob_protection ()
  29 {
  30   smob_protection_list = scm_cons (SCM_BOOL_F, SCM_EOL);
  31   scm_gc_protect_object (smob_protection_list);
  32 }
  33 ADD_SCM_INIT_FUNC (init_smob_protection, init_smob_protection);
  34
  35 LY_DEFINE (ly_smob_protects, "ly:smob-protects",
  36           0, 0, 0, (),
  37           "Return LilyPond's internal smob protection list.")
  38 {
  39   return scm_is_pair (smob_protection_list)
  40     ? scm_cdr (smob_protection_list)
  41     : SCM_EOL;
  42 }
  43
  44 void
  45 protect_smob (SCM smob, SCM *prot_cons)
  46 {
  47 #if 0
  48   SCM s = scm_cdr (smob_protection_list);
  49   while (scm_is_pair (s) && scm_car (s) == SCM_BOOL_F)
  50     {
  51       s = scm_cdr (s);
  52     }
  53   SCM prot = scm_cons (smob, s);
  54   scm_set_cdr_x (smob_protection_list,
  55                  prot);
  56   *prot_cons = prot;
  57 #else
  58   (void) prot_cons;
  59   scm_gc_protect_object (smob);
  60 #endif
  61 }
  62
  63 void
  64 unprotect_smob (SCM smob, SCM *prot_cons)
  65 {
  66 #if 1
  67   (void) prot_cons;
  68   scm_gc_unprotect_object (smob);
  69 #else
  70   SCM next = scm_cdr (*prot_cons);
  71
  72   if (next == SCM_EOL)
  73     scm_set_car_x (*prot_cons, SCM_BOOL_F);
  74   else
  75     {
  76       scm_set_car_x (*prot_cons, SCM_BOOL_F);
  77       while (scm_is_pair (next)
  78              && scm_car (next) == SCM_BOOL_F)
  79
  80         next = scm_cdr (next);
  81
  82       scm_set_cdr_x (*prot_cons, next);
  83     }
  84
  85   *prot_cons = SCM_EOL;
  86 #endif
  87 }