dlls/jscript/jsval.h

   1 /*
   2  * Copyright 2012 Jacek Caban for CodeWeavers
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #ifndef JSVAL_H
  20 #define JSVAL_H
  21
  22 #include "jsstr.h"
  23
  24 /*
  25  * jsval_t structure is used to represent JavaScript dynamically-typed values.
  26  * It's a (type,value) pair, usually represented as a structure of enum (type)
  27  * and union (value of given type). For both memory and speed performance, we
  28  * use tricks allowing storing both values as a struct with size equal to
  29  * size of double (that is 64-bit) on 32-bit systems. For that, we use the fact
  30  * that NaN value representation has 52 (almost) free bits.
  31  */
  32
  33 #ifdef __i386__
  34 #define JSVAL_DOUBLE_LAYOUT_PTR32
  35 #endif
  36
  37 #ifdef JSVAL_DOUBLE_LAYOUT_PTR32
  38 /* NaN exponent, quiet bit 0x80000 and our 0x10000 marker */
  39 #define JSV_VAL(x) (0x7ff90000|x)
  40 #else
  41 #define JSV_VAL(x) x
  42 #endif
  43
  44 typedef enum {
  45     JSV_UNDEFINED = JSV_VAL(1),
  46     JSV_NULL      = JSV_VAL(2),
  47     JSV_OBJECT    = JSV_VAL(3),
  48     JSV_STRING    = JSV_VAL(4),
  49     JSV_NUMBER    = JSV_VAL(5),
  50     JSV_BOOL      = JSV_VAL(6),
  51     JSV_VARIANT   = JSV_VAL(7)
  52 } jsval_type_t;
  53
  54 struct _jsval_t {
  55 #ifdef JSVAL_DOUBLE_LAYOUT_PTR32
  56     union {
  57         double n;
  58         struct {
  59             union {
  60                 IDispatch *obj;
  61                 jsstr_t *str;
  62                 BOOL b;
  63                 VARIANT *v;
  64                 UINT_PTR as_uintptr;
  65             } u;
  66             jsval_type_t tag;
  67         } s;
  68     } u;
  69 #else
  70     jsval_type_t type;
  71     union {
  72         IDispatch *obj;
  73         jsstr_t *str;
  74         double n;
  75         BOOL b;
  76         VARIANT *v;
  77     } u;
  78 #endif
  79 };
  80
  81 #ifdef JSVAL_DOUBLE_LAYOUT_PTR32
  82
  83 C_ASSERT(sizeof(jsval_t) == sizeof(double));
  84
  85 #define __JSVAL_TYPE(x) ((x).u.s.tag)
  86 #define __JSVAL_BOOL(x) ((x).u.s.u.b)
  87 #define __JSVAL_STR(x)  ((x).u.s.u.str)
  88 #define __JSVAL_OBJ(x)  ((x).u.s.u.obj)
  89 #define __JSVAL_VAR(x)  ((x).u.s.u.v)
  90
  91 #else
  92
  93 #define __JSVAL_TYPE(x) ((x).type)
  94 #define __JSVAL_BOOL(x) ((x).u.b)
  95 #define __JSVAL_STR(x)  ((x).u.str)
  96 #define __JSVAL_OBJ(x)  ((x).u.obj)
  97 #define __JSVAL_VAR(x)  ((x).u.v)
  98
  99 #endif
 100
 101 static inline jsval_t jsval_bool(BOOL b)
 102 {
 103     jsval_t ret;
 104     __JSVAL_TYPE(ret) = JSV_BOOL;
 105     __JSVAL_BOOL(ret) = b;
 106     return ret;
 107 }
 108
 109 static inline jsval_t jsval_string(jsstr_t *str)
 110 {
 111     jsval_t ret;
 112     __JSVAL_TYPE(ret) = JSV_STRING;
 113     __JSVAL_STR(ret) = str;
 114     return ret;
 115 }
 116
 117 static inline jsval_t jsval_disp(IDispatch *obj)
 118 {
 119     jsval_t ret;
 120     __JSVAL_TYPE(ret) = JSV_OBJECT;
 121     __JSVAL_OBJ(ret) = obj;
 122     return ret;
 123 }
 124
 125 static inline jsval_t jsval_obj(jsdisp_t *obj)
 126 {
 127     return jsval_disp(to_disp(obj));
 128 }
 129
 130 static inline jsval_t jsval_null(void)
 131 {
 132     jsval_t ret;
 133     __JSVAL_TYPE(ret) = JSV_NULL;
 134     __JSVAL_BOOL(ret) = FALSE;
 135     return ret;
 136 }
 137
 138 static inline jsval_t jsval_null_disp(void)
 139 {
 140     jsval_t ret;
 141     __JSVAL_TYPE(ret) = JSV_NULL;
 142     __JSVAL_BOOL(ret) = TRUE;
 143     return ret;
 144 }
 145
 146 static inline jsval_t jsval_undefined(void)
 147 {
 148     jsval_t ret;
 149     __JSVAL_TYPE(ret) = JSV_UNDEFINED;
 150     return ret;
 151 }
 152
 153 static inline jsval_t jsval_number(double n)
 154 {
 155     jsval_t ret;
 156 #ifdef JSVAL_DOUBLE_LAYOUT_PTR32
 157     ret.u.n = n;
 158     /* normalize NaN value */
 159     if((ret.u.s.tag & 0x7ff00000) == 0x7ff00000) {
 160         /* isinf */
 161         if(ret.u.s.tag & 0xfffff) {
 162             ret.u.s.tag = 0x7ff80000;
 163             ret.u.s.u.as_uintptr = ~0;
 164         }else if(ret.u.s.u.as_uintptr) {
 165             ret.u.s.tag = 0x7ff80000;
 166         }
 167     }
 168 #else
 169     ret.type = JSV_NUMBER;
 170     ret.u.n = n;
 171 #endif
 172     return ret;
 173 }
 174
 175 static inline BOOL is_object_instance(jsval_t v)
 176 {
 177     return __JSVAL_TYPE(v) == JSV_OBJECT;
 178 }
 179
 180 static inline BOOL is_undefined(jsval_t v)
 181 {
 182     return __JSVAL_TYPE(v) == JSV_UNDEFINED;
 183 }
 184
 185 static inline BOOL is_null(jsval_t v)
 186 {
 187     return __JSVAL_TYPE(v) == JSV_NULL;
 188 }
 189
 190 static inline BOOL is_null_disp(jsval_t v)
 191 {
 192     return is_null(v) && __JSVAL_BOOL(v);
 193 }
 194
 195 static inline BOOL is_string(jsval_t v)
 196 {
 197     return __JSVAL_TYPE(v) == JSV_STRING;
 198 }
 199
 200 static inline BOOL is_number(jsval_t v)
 201 {
 202 #ifdef JSVAL_DOUBLE_LAYOUT_PTR32
 203     return (v.u.s.tag & 0x7ff10000) != 0x7ff10000;
 204 #else
 205     return v.type == JSV_NUMBER;
 206 #endif
 207 }
 208
 209 static inline BOOL is_variant(jsval_t v)
 210 {
 211     return __JSVAL_TYPE(v) == JSV_VARIANT;
 212 }
 213
 214 static inline BOOL is_bool(jsval_t v)
 215 {
 216     return __JSVAL_TYPE(v) == JSV_BOOL;
 217 }
 218
 219 static inline jsval_type_t jsval_type(jsval_t v)
 220 {
 221 #ifdef JSVAL_DOUBLE_LAYOUT_PTR32
 222     return is_number(v) ? JSV_NUMBER : v.u.s.tag;
 223 #else
 224     return v.type;
 225 #endif
 226 }
 227
 228 static inline IDispatch *get_object(jsval_t v)
 229 {
 230     return __JSVAL_OBJ(v);
 231 }
 232
 233 static inline double get_number(jsval_t v)
 234 {
 235     return v.u.n;
 236 }
 237
 238 static inline jsstr_t *get_string(jsval_t v)
 239 {
 240     return __JSVAL_STR(v);
 241 }
 242
 243 static inline VARIANT *get_variant(jsval_t v)
 244 {
 245     return __JSVAL_VAR(v);
 246 }
 247
 248 static inline BOOL get_bool(jsval_t v)
 249 {
 250     return __JSVAL_BOOL(v);
 251 }
 252
 253 HRESULT variant_to_jsval(script_ctx_t*,VARIANT*,jsval_t*);
 254 HRESULT jsval_to_variant(jsval_t,VARIANT*);
 255 void jsval_release(jsval_t);
 256 HRESULT jsval_copy(jsval_t,jsval_t*);
 257
 258 #endif