libguile/weaks.h

   1 /* classes: h_files */
   2
   3 #ifndef SCM_WEAKS_H
   4 #define SCM_WEAKS_H
   5
   6 /* Copyright (C) 1995,1996,2000,2001, 2003, 2006, 2008, 2009 Free Software Foundation, Inc.
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * as published by the Free Software Foundation; either version 3 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21  * 02110-1301 USA
  22  */
  23
  24 \f
  25
  26 #include "libguile/__scm.h"
  27
  28 \f
  29
  30 #define SCM_WVECTF_WEAK_KEY   1
  31 #define SCM_WVECTF_WEAK_VALUE 2
  32
  33 #define SCM_WVECT_WEAK_KEY_P(x) (SCM_I_WVECT_EXTRA(x) & SCM_WVECTF_WEAK_KEY)
  34 #define SCM_WVECT_WEAK_VALUE_P(x) (SCM_I_WVECT_EXTRA(x) & SCM_WVECTF_WEAK_VALUE)
  35
  36 #define SCM_I_WVECT_TYPE(x)       (SCM_I_WVECT_EXTRA(x) & 7)
  37 #define SCM_I_SET_WVECT_TYPE(x,t) (SCM_I_SET_WVECT_EXTRA                \
  38                                    ((x), (SCM_I_WVECT_EXTRA (x) & ~7) | (t)))
  39 #define SCM_IS_WHVEC(X)           (SCM_I_WVECT_TYPE (X) == 1)
  40 #define SCM_IS_WHVEC_V(X)         (SCM_I_WVECT_TYPE (X) == 2)
  41 #define SCM_IS_WHVEC_B(X)         (SCM_I_WVECT_TYPE (X) == 3)
  42 #define SCM_IS_WHVEC_ANY(X)       (SCM_I_WVECT_TYPE (X) != 0)
  43
  44 \f
  45 /* Weak pairs.  */
  46
  47 SCM_INTERNAL SCM scm_weak_car_pair (SCM car, SCM cdr);
  48 SCM_INTERNAL SCM scm_weak_cdr_pair (SCM car, SCM cdr);
  49 SCM_INTERNAL SCM scm_doubly_weak_pair (SCM car, SCM cdr);
  50
  51 /* Testing the weak component(s) of a cell for reachability.  */
  52 #define SCM_WEAK_PAIR_WORD_DELETED_P(_cell, _word)              \
  53   (SCM_CELL_OBJECT ((_cell), (_word)) == SCM_PACK (NULL))
  54 #define SCM_WEAK_PAIR_CAR_DELETED_P(_cell)      \
  55   (SCM_WEAK_PAIR_WORD_DELETED_P ((_cell), 0))
  56 #define SCM_WEAK_PAIR_CDR_DELETED_P(_cell)      \
  57   (SCM_WEAK_PAIR_WORD_DELETED_P ((_cell), 1))
  58
  59 #define SCM_WEAK_PAIR_DELETED_P(_cell)          \
  60   ((SCM_WEAK_PAIR_CAR_DELETED_P (_cell))        \
  61    || (SCM_WEAK_PAIR_CDR_DELETED_P (_cell)))
  62
  63 /* Accessing the components of a weak cell.  These return `SCM_UNDEFINED' if
  64    the car/cdr has been collected.  */
  65 #define SCM_WEAK_PAIR_WORD(_cell, _word)                \
  66   (SCM_WEAK_PAIR_WORD_DELETED_P ((_cell), (_word))      \
  67    ? SCM_UNDEFINED                                      \
  68    : SCM_CELL_OBJECT ((_cell), (_word)))
  69 #define SCM_WEAK_PAIR_CAR(_cell)  (SCM_WEAK_PAIR_WORD ((_cell), 0))
  70 #define SCM_WEAK_PAIR_CDR(_cell)  (SCM_WEAK_PAIR_WORD ((_cell), 1))
  71
  72
  73 \f
  74 /* Weak vectors and weak hash tables.  */
  75
  76 SCM_API SCM scm_make_weak_vector (SCM k, SCM fill);
  77 SCM_API SCM scm_weak_vector (SCM l);
  78 SCM_API SCM scm_weak_vector_p (SCM x);
  79 SCM_API SCM scm_make_weak_key_alist_vector (SCM k);
  80 SCM_API SCM scm_make_weak_value_alist_vector (SCM k);
  81 SCM_API SCM scm_make_doubly_weak_alist_vector (SCM k);
  82 SCM_API SCM scm_weak_key_alist_vector_p (SCM x);
  83 SCM_API SCM scm_weak_value_alist_vector_p (SCM x);
  84 SCM_API SCM scm_doubly_weak_alist_vector_p (SCM x);
  85 SCM_INTERNAL SCM scm_init_weaks_builtins (void);
  86 SCM_INTERNAL void scm_weaks_prehistory (void);
  87 SCM_INTERNAL void scm_init_weaks (void);
  88
  89 SCM_INTERNAL void scm_i_init_weak_vectors_for_gc (void);
  90 SCM_INTERNAL void scm_i_mark_weak_vector (SCM w);
  91 SCM_INTERNAL int scm_i_mark_weak_vectors_non_weaks (void);
  92 SCM_INTERNAL void scm_i_remove_weaks_from_weak_vectors (void);
  93
  94
  95 #endif  /* SCM_WEAKS_H */
  96
  97 /*
  98   Local Variables:
  99   c-file-style: "gnu"
 100   End:
 101 */