libguile/stacks.h

   1 /* classes: h_files */
   2
   3 #ifndef SCM_STACKS_H
   4 #define SCM_STACKS_H
   5
   6 /* Copyright (C) 1995,1996,2000,2001 Free Software Foundation, Inc.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this software; see the file COPYING.  If not, write to
  20  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  21  * Boston, MA 02111-1307 USA
  22  *
  23  * As a special exception, the Free Software Foundation gives permission
  24  * for additional uses of the text contained in its release of GUILE.
  25  *
  26  * The exception is that, if you link the GUILE library with other files
  27  * to produce an executable, this does not by itself cause the
  28  * resulting executable to be covered by the GNU General Public License.
  29  * Your use of that executable is in no way restricted on account of
  30  * linking the GUILE library code into it.
  31  *
  32  * This exception does not however invalidate any other reasons why
  33  * the executable file might be covered by the GNU General Public License.
  34  *
  35  * This exception applies only to the code released by the
  36  * Free Software Foundation under the name GUILE.  If you copy
  37  * code from other Free Software Foundation releases into a copy of
  38  * GUILE, as the General Public License permits, the exception does
  39  * not apply to the code that you add in this way.  To avoid misleading
  40  * anyone as to the status of such modified files, you must delete
  41  * this exception notice from them.
  42  *
  43  * If you write modifications of your own for GUILE, it is your choice
  44  * whether to permit this exception to apply to your modifications.
  45  * If you do not wish that, delete this exception notice.
  46  *
  47  * The author can be reached at djurfeldt@nada.kth.se
  48  * Mikael Djurfeldt, SANS/NADA KTH, 10044 STOCKHOLM, SWEDEN */
  49
  50 \f
  51
  52 #include "libguile/__scm.h"
  53
  54 /* {Frames and stacks}
  55  */
  56
  57 typedef struct scm_t_info_frame {
  58   /* SCM flags; */
  59   scm_t_bits flags;
  60   SCM source;
  61   SCM proc;
  62   SCM args;
  63 } scm_t_info_frame;
  64 #define SCM_FRAME_N_SLOTS (sizeof (scm_t_info_frame) / sizeof (SCM))
  65
  66 #define SCM_STACK(obj) ((scm_t_stack *) SCM_STRUCT_DATA (obj))
  67 #define SCM_STACK_LAYOUT "pwuourpW"
  68 typedef struct scm_t_stack {
  69   SCM id;                       /* Stack id */
  70   scm_t_info_frame *frames;     /* Info frames */
  71   unsigned long length;         /* Stack length */
  72   unsigned long tail_length;
  73   scm_t_info_frame tail[1];
  74 } scm_t_stack;
  75
  76 extern SCM scm_t_stackype;
  77
  78 #define SCM_STACKP(obj) (SCM_STRUCTP (obj) && SCM_EQ_P (SCM_STRUCT_VTABLE (obj), scm_t_stackype))
  79 #define SCM_STACK_LENGTH(stack) (SCM_STACK (stack) -> length)
  80
  81 #define SCM_FRAMEP(obj) \
  82   (SCM_CONSP (obj) && SCM_STACKP (SCM_CAR (obj)) \
  83    && SCM_INUMP (SCM_CDR (obj)) && SCM_INUM (SCM_CDR (obj)) >= 0 \
  84    && ((unsigned long int) SCM_INUM (SCM_CDR (obj)) \
  85        < SCM_STACK_LENGTH (SCM_CAR (obj))))
  86
  87 #define SCM_FRAME_REF(frame, slot) \
  88 (SCM_STACK (SCM_CAR (frame)) -> frames[SCM_INUM (SCM_CDR (frame))].slot) \
  89
  90 #define SCM_FRAME_NUMBER(frame) \
  91 (SCM_BACKWARDS_P \
  92  ? SCM_INUM (SCM_CDR (frame)) \
  93  : (SCM_STACK_LENGTH (SCM_CAR (frame)) \
  94     - SCM_INUM (SCM_CDR (frame)) \
  95     - 1)) \
  96
  97 #define SCM_FRAME_FLAGS(frame) SCM_FRAME_REF (frame, flags)
  98 #define SCM_FRAME_SOURCE(frame) SCM_FRAME_REF (frame, source)
  99 #define SCM_FRAME_PROC(frame) SCM_FRAME_REF (frame, proc)
 100 #define SCM_FRAME_ARGS(frame) SCM_FRAME_REF (frame, args)
 101 #define SCM_FRAME_PREV(frame) scm_frame_previous (frame)
 102 #define SCM_FRAME_NEXT(frame) scm_frame_next (frame)
 103
 104 #define SCM_FRAMEF_VOID         (1L << 2)
 105 #define SCM_FRAMEF_REAL         (1L << 3)
 106 #define SCM_FRAMEF_PROC         (1L << 4)
 107 #define SCM_FRAMEF_EVAL_ARGS    (1L << 5)
 108 #define SCM_FRAMEF_OVERFLOW     (1L << 6)
 109
 110 #define SCM_FRAME_VOID_P(f)       (SCM_FRAME_FLAGS (f) & SCM_FRAMEF_VOID)
 111 #define SCM_FRAME_REAL_P(f)       (SCM_FRAME_FLAGS (f) & SCM_FRAMEF_REAL)
 112 #define SCM_FRAME_PROC_P(f)       (SCM_FRAME_FLAGS (f) & SCM_FRAMEF_PROC)
 113 #define SCM_FRAME_EVAL_ARGS_P(f)  (SCM_FRAME_FLAGS (f) & SCM_FRAMEF_EVAL_ARGS)
 114 #define SCM_FRAME_OVERFLOW_P(f)   (SCM_FRAME_FLAGS (f) & SCM_FRAMEF_OVERFLOW)
 115
 116 \f
 117
 118 SCM scm_stack_p (SCM obj);
 119 SCM scm_make_stack (SCM obj, SCM args);
 120 SCM scm_stack_id (SCM stack);
 121 SCM scm_stack_ref (SCM stack, SCM i);
 122 SCM scm_stack_length (SCM stack);
 123
 124 SCM scm_frame_p (SCM obj);
 125 SCM scm_last_stack_frame (SCM obj);
 126 SCM scm_frame_number (SCM frame);
 127 SCM scm_frame_source (SCM frame);
 128 SCM scm_frame_procedure (SCM frame);
 129 SCM scm_frame_arguments (SCM frame);
 130 SCM scm_frame_previous (SCM frame);
 131 SCM scm_frame_next (SCM frame);
 132 SCM scm_frame_real_p (SCM frame);
 133 SCM scm_frame_procedure_p (SCM frame);
 134 SCM scm_frame_evaluating_args_p (SCM frame);
 135 SCM scm_frame_overflow_p (SCM frame);
 136
 137 void scm_init_stacks (void);
 138
 139 #endif  /* SCM_STACKS_H */
 140
 141 /*
 142   Local Variables:
 143   c-file-style: "gnu"
 144   End:
 145 */