libguile/private-gc.h

   1 /*
   2  * private-gc.h - private declarations for garbage collection.
   3  *
   4  * Copyright (C) 2002, 03, 04, 05, 06, 07, 08, 09 Free Software Foundation, Inc.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public License
   8  * as published by the Free Software Foundation; either version 3 of
   9  * the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19  * 02110-1301 USA
  20  */
  21
  22 #ifndef SCM_PRIVATE_GC
  23 #define SCM_PRIVATE_GC
  24
  25 #include  "_scm.h"
  26
  27 /* {heap tuning parameters}
  28  *
  29  * These are parameters for controlling memory allocation.  The heap
  30  * is the area out of which scm_cons, and object headers are allocated.
  31  *
  32  * Each heap cell is 8 bytes on a 32 bit machine and 16 bytes on a
  33  * 64 bit machine.  The units of the _SIZE parameters are bytes.
  34  * Cons pairs and object headers occupy one heap cell.
  35  */
  36
  37
  38 #define SCM_DEFAULT_INIT_HEAP_SIZE_2 32*1024
  39
  40 #define SCM_DOUBLECELL_ALIGNED_P(x)  (((2 * sizeof (scm_t_cell) - 1) & SCM_UNPACK (x)) == 0)
  41
  42
  43 SCM_INTERNAL int scm_getenv_int (const char *var, int def);
  44
  45
  46 typedef enum { return_on_error, abort_on_error } policy_on_error;
  47
  48
  49 #define SCM_MAX(A, B) ((A) > (B) ? (A) : (B))
  50 #define SCM_MIN(A, B) ((A) < (B) ? (A) : (B))
  51
  52 /* CELL_P checks a random word whether it has the right form for a
  53    pointer to a cell.  Use scm_i_find_heap_segment_containing_object
  54    to find out whether it actually points to a real cell.
  55
  56    The right form for a cell pointer is this: the low three bits must
  57    be scm_tc3_cons, and when the scm_tc3_cons tag is stripped, the
  58    resulting pointer must be correctly aligned.
  59    scm_i_initialize_heap_segment_data guarantees that the test below
  60    works.
  61 */
  62 #define CELL_P(x)  ((SCM_UNPACK(x) & (sizeof(scm_t_cell)-1)) == scm_tc3_cons)
  63
  64 SCM_INTERNAL char const *scm_i_tag_name (scm_t_bits tag); /* MOVEME */
  65
  66 #endif