libguile/struct.h

   1 /* classes: h_files */
   2
   3 #ifndef STRUCTH
   4 #define STRUCTH
   5 /*      Copyright (C) 1995, 1997, 1999, 2000 Free Software Foundation, Inc.
   6  *
   7  * This program 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 2, or (at your option)
  10  * any later version.
  11  *
  12  * This program 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 this software; see the file COPYING.  If not, write to
  19  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  20  * Boston, MA 02111-1307 USA
  21  *
  22  * As a special exception, the Free Software Foundation gives permission
  23  * for additional uses of the text contained in its release of GUILE.
  24  *
  25  * The exception is that, if you link the GUILE library with other files
  26  * to produce an executable, this does not by itself cause the
  27  * resulting executable to be covered by the GNU General Public License.
  28  * Your use of that executable is in no way restricted on account of
  29  * linking the GUILE library code into it.
  30  *
  31  * This exception does not however invalidate any other reasons why
  32  * the executable file might be covered by the GNU General Public License.
  33  *
  34  * This exception applies only to the code released by the
  35  * Free Software Foundation under the name GUILE.  If you copy
  36  * code from other Free Software Foundation releases into a copy of
  37  * GUILE, as the General Public License permits, the exception does
  38  * not apply to the code that you add in this way.  To avoid misleading
  39  * anyone as to the status of such modified files, you must delete
  40  * this exception notice from them.
  41  *
  42  * If you write modifications of your own for GUILE, it is your choice
  43  * whether to permit this exception to apply to your modifications.
  44  * If you do not wish that, delete this exception notice.  */
  45
  46 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  47    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  48 \f
  49
  50 #include "libguile/__scm.h"
  51 #include "libguile/print.h"
  52
  53 \f
  54
  55 /* Number of words with negative index */
  56 #define scm_struct_n_extra_words 4
  57 #define scm_struct_entity_n_extra_words 6
  58
  59 /* These are how the initial words of a vtable are allocated. */
  60 #define scm_struct_i_setter     -6 /* Setter */
  61 #define scm_struct_i_procedure  -5 /* Optional procedure slot */
  62 #define scm_struct_i_free       -4 /* Destructor */
  63 #define scm_struct_i_ptr        -3 /* Start of block (see alloc_struct) */
  64 #define scm_struct_i_n_words    -2 /* How many words allocated to this struct? */
  65 #define scm_struct_i_size       -1 /* Instance size */
  66 #define scm_struct_i_flags      -1 /* Upper 12 bits used as flags */
  67 #define scm_vtable_index_layout  0 /* A symbol describing the physical arrangement of this type. */
  68 #define scm_vtable_index_vcell   1 /* An opaque word, managed by the garbage collector.  */
  69 #define scm_vtable_index_vtable  2 /* A pointer to the handle for this vtable. */
  70 #define scm_vtable_index_printer 3 /* A printer for this struct type. */
  71 #define scm_vtable_offset_user   4 /* Where do user fields start? */
  72
  73 typedef scm_sizet (*scm_struct_free_t) (SCM *vtable, SCM *data);
  74
  75 #define SCM_STRUCTF_MASK   (0xFFF << 20)
  76 #define SCM_STRUCTF_ENTITY (1L << 30) /* Indicates presence of proc slots */
  77 #define SCM_STRUCTF_LIGHT  (1L << 31) /* Light representation
  78                                          (no hidden words) */
  79
  80 #define SCM_STRUCTP(X)                  (SCM_NIMP(X) && (SCM_TYP3(X) == scm_tc3_cons_gloc))
  81 #define SCM_STRUCT_DATA(X)              ((scm_bits_t *) SCM_CELL_WORD_1 (X))
  82 #define SCM_STRUCT_VTABLE_DATA(X)       ((scm_bits_t *) (SCM_CELL_WORD_0 (X) - 1))
  83
  84 #define SCM_STRUCT_LAYOUT(X)            (SCM_PACK (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_layout]))
  85 #define SCM_SET_STRUCT_LAYOUT(X, v)     (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_layout] = SCM_UNPACK (v))
  86
  87 #define SCM_STRUCT_VTABLE(X)            (SCM_PACK (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_vtable]))
  88 #define SCM_STRUCT_PRINTER(X)           (SCM_PACK (SCM_STRUCT_VTABLE_DATA (X) [scm_vtable_index_printer]))
  89 #define SCM_SET_VTABLE_DESTRUCTOR(X, D) (SCM_STRUCT_DATA(X)[scm_struct_i_free] = (SCM) D)
  90 /* Efficiency is important in the following macro, since it's used in GC */
  91 #define SCM_LAYOUT_TAILP(X)             (((X) & 32) == 0) /* R, W or O */
  92
  93 #define SCM_STRUCT_TABLE_NAME(X) SCM_CAR (X)
  94 #define SCM_SET_STRUCT_TABLE_NAME(X, NAME) SCM_SETCAR (X, NAME)
  95 #define SCM_STRUCT_TABLE_CLASS(X) SCM_CDR (X)
  96 #define SCM_SET_STRUCT_TABLE_CLASS(X, CLASS) SCM_SETCDR (X, CLASS)
  97 extern SCM scm_struct_table;
  98
  99 \f
 100
 101 extern SCM *scm_alloc_struct (int n_words,
 102                               int n_extra,
 103                               char *who);
 104 extern scm_sizet scm_struct_free_0 (SCM *vtable, SCM *data);
 105 extern scm_sizet scm_struct_free_light (SCM *vtable, SCM *data);
 106 extern scm_sizet scm_struct_free_standard (SCM *vtable, SCM *data);
 107 extern scm_sizet scm_struct_free_entity (SCM *vtable, SCM *data);
 108 extern void scm_struct_init (SCM handle, int tail_elts, SCM inits);
 109 extern SCM scm_make_struct_layout (SCM fields);
 110 extern SCM scm_struct_p (SCM x);
 111 extern SCM scm_struct_vtable_p (SCM x);
 112 extern SCM scm_make_struct (SCM vtable, SCM tail_array_size, SCM init);
 113 extern SCM scm_make_vtable_vtable (SCM extra_fields, SCM tail_array_size, SCM init);
 114 extern SCM scm_struct_ref (SCM handle, SCM pos);
 115 extern SCM scm_struct_set_x (SCM handle, SCM pos, SCM val);
 116 extern SCM scm_struct_vtable (SCM handle);
 117 extern SCM scm_struct_vtable_tag (SCM handle);
 118 extern unsigned int scm_struct_ihashq (SCM obj, unsigned int n);
 119 extern SCM scm_struct_create_handle (SCM obj);
 120 extern SCM scm_struct_vtable_name (SCM vtable);
 121 extern SCM scm_set_struct_vtable_name_x (SCM vtable, SCM name);
 122 extern void scm_print_struct (SCM exp, SCM port, scm_print_state *);
 123 extern void scm_init_struct (void);
 124
 125 #endif  /* STRUCTH */
 126
 127 /*
 128   Local Variables:
 129   c-file-style: "gnu"
 130   End:
 131 */