libguile/stacks.h

   1 /* classes: h_files */
   2
   3 #ifndef STACKSH
   4 #define STACKSH
   5 /*      Copyright (C) 1995,1996 Free Software Foundation
   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  * The author can be reached at djurfeldt@nada.kth.se
  47  * Mikael Djurfeldt, SANS/NADA KTH, 10044 STOCKHOLM, SWEDEN */
  48
  49 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  50    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  51 \f
  52
  53 #include "libguile/__scm.h"
  54
  55 /* {Frames and stacks}
  56  */
  57
  58 typedef struct scm_info_frame {
  59   //SCM flags;
  60   scm_bits_t flags;
  61   SCM source;
  62   SCM proc;
  63   SCM args;
  64 } scm_info_frame;
  65 #define SCM_FRAME_N_SLOTS (sizeof (scm_info_frame) / sizeof (SCM))
  66
  67 #define SCM_STACK(obj) ((scm_stack *) SCM_STRUCT_DATA (obj))
  68 #define SCM_STACK_LAYOUT "pwuourpW"
  69 typedef struct scm_stack {
  70   SCM id;                       /* Stack id */
  71   scm_info_frame *frames;       /* Info frames */
  72   unsigned int length;          /* Stack length */
  73   unsigned int tail_length;
  74   scm_info_frame tail[1];
  75 } scm_stack;
  76
  77 extern SCM scm_stack_type;
  78
  79 #define SCM_STACKP(obj) (SCM_NIMP(obj) && \
  80                          SCM_STRUCTP (obj) && SCM_STRUCT_VTABLE (obj) == scm_stack_type)
  81 #define SCM_STACK_LENGTH(stack) (SCM_STACK (stack) -> length)
  82
  83 #define SCM_FRAMEP(obj) (SCM_CONSP (obj) \
  84                          && SCM_STACKP (SCM_CAR (obj)) \
  85                          && SCM_INUMP (SCM_CDR (obj))) \
  86
  87
  88 #define SCM_FRAME_REF(frame, slot) \
  89 (SCM_STACK (SCM_CAR (frame)) -> frames[SCM_INUM (SCM_CDR (frame))].slot) \
  90
  91 #define SCM_FRAME_NUMBER(frame) \
  92 (SCM_BACKWARDS_P \
  93  ? SCM_INUM (SCM_CDR (frame)) \
  94  : (SCM_STACK_LENGTH (SCM_CAR (frame)) \
  95     - SCM_INUM (SCM_CDR (frame)) \
  96     - 1)) \
  97
  98 #define SCM_FRAME_FLAGS(frame) SCM_FRAME_REF (frame, flags)
  99 #define SCM_FRAME_SOURCE(frame) SCM_FRAME_REF (frame, source)
 100 #define SCM_FRAME_PROC(frame) SCM_FRAME_REF (frame, proc)
 101 #define SCM_FRAME_ARGS(frame) SCM_FRAME_REF (frame, args)
 102 #define SCM_FRAME_PREV(frame) scm_frame_previous (frame)
 103 #define SCM_FRAME_NEXT(frame) scm_frame_next (frame)
 104
 105 #define SCM_FRAMEF_VOID         (1L << 2)
 106 #define SCM_FRAMEF_REAL         (1L << 3)
 107 #define SCM_FRAMEF_PROC         (1L << 4)
 108 #define SCM_FRAMEF_EVAL_ARGS    (1L << 5)
 109 #define SCM_FRAMEF_OVERFLOW     (1L << 6)
 110
 111 #define SCM_FRAME_VOID_P(frame) (SCM_UNPACK (SCM_FRAME_FLAGS (frame)) & SCM_FRAMEF_VOID)
 112 #define SCM_FRAME_REAL_P(frame) (SCM_UNPACK (SCM_FRAME_FLAGS (frame)) & SCM_FRAMEF_REAL)
 113 #define SCM_FRAME_PROC_P(frame) (SCM_UNPACK (SCM_FRAME_FLAGS (frame)) & SCM_FRAMEF_PROC)
 114 #define SCM_FRAME_EVAL_ARGS_P(frame) (SCM_UNPACK (SCM_FRAME_FLAGS (frame)) & SCM_FRAMEF_EVAL_ARGS)
 115 #define SCM_FRAME_OVERFLOW_P(frame) (SCM_UNPACK (SCM_FRAME_FLAGS (frame)) & SCM_FRAMEF_OVERFLOW)
 116
 117 \f
 118
 119 SCM scm_stack_p (SCM obj);
 120 SCM scm_make_stack (SCM args);
 121 SCM scm_stack_id (SCM stack);
 122 SCM scm_stack_ref (SCM stack, SCM i);
 123 SCM scm_stack_length (SCM stack);
 124
 125 SCM scm_frame_p (SCM obj);
 126 SCM scm_last_stack_frame (SCM obj);
 127 SCM scm_frame_number (SCM frame);
 128 SCM scm_frame_source (SCM frame);
 129 SCM scm_frame_procedure (SCM frame);
 130 SCM scm_frame_arguments (SCM frame);
 131 SCM scm_frame_previous (SCM frame);
 132 SCM scm_frame_next (SCM frame);
 133 SCM scm_frame_real_p (SCM frame);
 134 SCM scm_frame_procedure_p (SCM frame);
 135 SCM scm_frame_evaluating_args_p (SCM frame);
 136 SCM scm_frame_overflow_p (SCM frame);
 137
 138
 139 void scm_init_stacks (void);
 140
 141 #endif /* STACKSH */
 142
 143 /*
 144   Local Variables:
 145   c-file-style: "gnu"
 146   End:
 147 */