lib/nit_common.h

   1 #ifndef NIT_COMMON_H
   2 #define NIT_COMMON_H
   3
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7
   8 /* *** Types *** */
   9 typedef int (*fun_t)(int);                                      /* generic function pointer */
  10 typedef unsigned int cid_t;                                     /* class identifier */
  11 typedef unsigned long int val_t;        /* value (everything is a val_t) */
  12 typedef union obj_tu {union classtable_elt_tu * vft; val_t attr;} *obj_t; /* standard object */
  13 typedef union classtable_elt_tu { int i; fun_t f; cid_t cid;} classtable_elt_t; /* classtable element */
  14
  15 typedef classtable_elt_t * classtable_t;                        /* classtable */
  16
  17 /*****************************************************************************
  18  * Types macros (primitive and less primitives) ******************************
  19  *****************************************************************************
  20  *
  21  * ** types are: **
  22  *
  23  * OBJ  (obj_t) : standard object representation (including boxes + NIL)
  24  * Int  (int)   : integers
  25  * Char (car)   : characters
  26  * Bool (int)   : booleans (true or false)
  27  *
  28  * X    (x_t)   : generic representatio of the previous four types
  29  *
  30  * ** macros are: **
  31  *
  32  * int ISX(val_t v)             : true if v is a X
  33  * x_t VAL2X(val_t v)           : convert a val_t to a primitive type (you should check ISX before)
  34  * val_t X2VAL(x_t x)           : convert a type to a val_t
  35  * int XTAG                     : numeric identifier of a type
  36  * int TAG(val_t v)             : return the XTAG (ie TAG(Char2VAL('e')) == CharTag)
  37  *
  38  * classtable_t VAL2VFT(val_t v): the virtual function table of a value
  39  *
  40  * val_t NIT_NULL               : the instance of the None class
  41  *****************************************************************************/
  42
  43 #define TAG(x) ((int)(x) & 3)
  44 #ifndef IntTAG
  45 #       define IntTAG 1
  46 #endif
  47 #define TAG_Int(x) ((val_t)(((x)<<2)|IntTAG))
  48 #define UNTAG_Int(x) ((int)(x)>>2)
  49 #ifndef CharTAG
  50 #       define CharTAG 2
  51 #endif
  52 #define TAG_Char(x) ((val_t)((((int)(x))<<2)|CharTAG))
  53 #define UNTAG_Char(x) ((char)((int)(x)>>2))
  54 #ifndef BoolTAG
  55 #       define BoolTAG 3
  56 #endif
  57 #define TAG_Bool(x) ((val_t)(((x)<<2)|BoolTAG))
  58 #define UNTAG_Bool(x) ((int)(x)>>2)
  59 #ifndef OBJTAG
  60 #       define OBJTAG 0
  61 #endif
  62
  63 #define ISOBJ(x) (TAG((x)) == OBJTAG)
  64 #define VAL2OBJ(x) ((obj_t)(x))
  65 #define OBJ2VAL(o) ((val_t)(o))
  66 #define VAL2VFT(x) (ISOBJ(x) ? VAL2OBJ(x)->vft : TAG2VFT[TAG(x)])
  67 /*#define VAL2CID(x) (ISOBJ(x) ? (VAL2OBJ(x)->vft->cid) : (-TAG(x)))*/
  68 #define VAL2CID(x) (VAL2OBJ(x)->vft->cid)
  69
  70 #define NIT_NULL ((val_t)0)
  71 #define ISNULL(x) ((x)==NIT_NULL)
  72
  73 /* Equal comparaison */
  74 /* O = Non nil object ; N = Object or nil ; P = Primitive */
  75 #define OBJ_IS_BOX(x) ((VAL2OBJ(x)->vft->i) < 0)
  76 #define IS_BOX(x) (ISOBJ(x) && OBJ_IS_BOX(x))
  77 #define IS_EQUAL_BOX(x, y) (ISOBJ(y) && (VAL2OBJ(x)[1].vft==VAL2OBJ(y)[1].vft) && (VAL2OBJ(x)->vft==VAL2OBJ(y)->vft))
  78 #define IS_EQUAL_OO(x, y) ((x)==(y) || (IS_BOX(x) && IS_EQUAL_BOX((x), (y))))
  79 #define IS_EQUAL_ON(x, y) ((x)==(y) || (IS_BOX(x) && !ISNULL(y) && IS_EQUAL_BOX((x), (y))))
  80 #define IS_EQUAL_NN(x, y) ((x)==(y) || (!ISNULL(x) && IS_BOX(x) && !ISNULL(y) && IS_EQUAL_BOX((x), (y))))
  81
  82 /* Subclass comparaison */
  83 /* check is e is a subtype of c2 */
  84 /* Warning, only subclasse comparaison is performed, not subtype */
  85 /* e is a val (not nil) */
  86 /* c a class name (eg: Int) */
  87 #define VALISA(e, c) (VAL2VFT(e)[COLOR_ ## c].cid == (cid_t) ID_ ## c)
  88 #define OBJISA(e, c) (VAL2OBJ(e)->vft[COLOR_ ## c].cid == (cid_t) ID_ ## c)
  89
  90 #define VAL_ISA(e, c, i) (VAL2VFT((e))[(c)].cid == (cid_t)(i))
  91
  92 void * alloc(size_t);
  93 extern val_t G_args;
  94 extern val_t G_stdin;
  95 extern val_t G_stdout;
  96 extern val_t G_stderr;
  97 extern val_t G_sys;
  98
  99 extern int glob_argc;
 100 extern char ** glob_argv;
 101
 102 struct trace_t {
 103         struct trace_t *prev;
 104         const char *text;
 105 };
 106 extern struct trace_t *tracehead;
 107 typedef enum {true = (1==1),false = (0==1)} bool;
 108
 109 void nit_exit(int);
 110
 111 #define CALL(r,c) ((VAL2VFT(r)[c].f))
 112 #define ATTR(r,c) (*(val_t*)(VAL2OBJ(r)+c))
 113 #define ATTRS(r,c,o) ((VAL2OBJ(r)+VAL2VFT(r)[c].i)[o].attr)
 114
 115 void prepare_signals(void);
 116 extern classtable_t TAG2VFT[4];
 117 #endif