trunk/js/jsarray.h

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code, released
 * March 31, 1998.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef jsarray_h___
#define jsarray_h___
/*
 * JS Array interface.
 */
#include "jsprvtd.h"
#include "jspubtd.h"
#include "jsobj.h"

JS_BEGIN_EXTERN_C

#define ARRAY_CAPACITY_MIN      7

/* Generous sanity-bound on length (in elements) of array initialiser. */
#define ARRAY_INIT_LIMIT        JS_BIT(24)

extern JSBool
js_IdIsIndex(jsval id, jsuint *indexp);

extern JSClass js_ArrayClass, js_SlowArrayClass;

#define OBJ_IS_DENSE_ARRAY(cx,obj)  (OBJ_GET_CLASS(cx, obj) == &js_ArrayClass)

#define OBJ_IS_ARRAY(cx,obj)    (OBJ_IS_DENSE_ARRAY(cx, obj) ||               \
                                 OBJ_GET_CLASS(cx, obj) == &js_SlowArrayClass)

/*
 * Dense arrays are not native (OBJ_IS_NATIVE(cx, aobj) for a dense array aobj
 * results in false, meaning aobj->map does not point to a JSScope).
 *
 * But Array methods are called via aobj.sort(), e.g., and the interpreter and
 * the trace recorder must consult the property cache in order to perform well.
 * The cache works only for native objects.
 *
 * Therefore the interpreter (js_Interpret in JSOP_GETPROP and JSOP_CALLPROP)
 * and js_GetPropertyHelper use this inline function to skip up one link in the
 * prototype chain when obj is a dense array, in order to find a native object
 * (to wit, Array.prototype) in which to probe for cached methods.
 *
 * Note that setting aobj.__proto__ for a dense array aobj turns aobj into a
 * slow array, avoiding the neede to skip.
 *
 * Callers of js_GetProtoIfDenseArray must take care to use the original object
 * (obj) for the |this| value of a getter, setter, or method call (bug 476447).
 */
static JS_INLINE JSObject *
js_GetProtoIfDenseArray(JSContext *cx, JSObject *obj)
{
    return OBJ_IS_DENSE_ARRAY(cx, obj) ? OBJ_GET_PROTO(cx, obj) : obj;
}

extern JSObject *
js_InitArrayClass(JSContext *cx, JSObject *obj);

extern JSObject *
js_NewArrayObject(JSContext *cx, jsuint length, jsval *vector,
                  JSBool holey = JS_FALSE);

/* Create an array object that starts out already made slow/sparse. */
extern JSObject *
js_NewSlowArrayObject(JSContext *cx);

extern JSBool
js_MakeArraySlow(JSContext *cx, JSObject *obj);

#define JSSLOT_ARRAY_LENGTH            JSSLOT_PRIVATE
#define JSSLOT_ARRAY_COUNT             (JSSLOT_ARRAY_LENGTH + 1)
#define JSSLOT_ARRAY_UNUSED            (JSSLOT_ARRAY_COUNT + 1)

static JS_INLINE uint32
js_DenseArrayCapacity(JSObject *obj)
{
    JS_ASSERT(OBJ_IS_DENSE_ARRAY(BOGUS_CX, obj));
    return obj->dslots ? (uint32) obj->dslots[-1] : 0;
}

static JS_INLINE void
js_SetDenseArrayCapacity(JSObject *obj, uint32 capacity)
{
    JS_ASSERT(OBJ_IS_DENSE_ARRAY(BOGUS_CX, obj));
    JS_ASSERT(obj->dslots);
    obj->dslots[-1] = (jsval) capacity;
}

extern JSBool
js_GetLengthProperty(JSContext *cx, JSObject *obj, jsuint *lengthp);

extern JSBool
js_SetLengthProperty(JSContext *cx, JSObject *obj, jsdouble length);

extern JSBool
js_HasLengthProperty(JSContext *cx, JSObject *obj, jsuint *lengthp);

extern JSBool JS_FASTCALL
js_IndexToId(JSContext *cx, jsuint index, jsid *idp);

/*
 * Test whether an object is "array-like".  Currently this means whether obj
 * is an Array or an arguments object.  We would like an API, and probably a
 * way in the language, to bless other objects as array-like: having indexed
 * properties, and a 'length' property of uint32 value equal to one more than
 * the greatest index.
 */
extern JSBool
js_IsArrayLike(JSContext *cx, JSObject *obj, JSBool *answerp, jsuint *lengthp);

/*
 * JS-specific merge sort function.
 */
typedef JSBool (*JSComparator)(void *arg, const void *a, const void *b,
                               int *result);
/*
 * NB: vec is the array to be sorted, tmp is temporary space at least as big
 * as vec. Both should be GC-rooted if appropriate.
 *
 * The sorted result is in vec. vec may be in an inconsistent state if the
 * comparator function cmp returns an error inside a comparison, so remember
 * to check the return value of this function.
 */
extern JS_REQUIRES_STACK JSBool
js_MergeSort(void *vec, size_t nel, size_t elsize, JSComparator cmp,
             void *arg, void *tmp);

#ifdef DEBUG_ARRAYS
extern JSBool
js_ArrayInfo(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval);
#endif

extern JSBool JS_FASTCALL
js_ArrayCompPush(JSContext *cx, JSObject *obj, jsval v);

/*
 * Fast dense-array-to-buffer conversions.
 *
 * If the array is a dense array, fill [offset..offset+count] values
 * into destination, assuming that types are consistent.  Return
 * JS_TRUE if successful, otherwise JS_FALSE -- note that the
 * destination buffer may be modified even if JS_FALSE is returned
 * (e.g. due to finding an inappropriate type later on in the array).
 * If JS_FALSE is returned, no error conditions or exceptions are set
 * on the context.
 *
 * For ArrayToJSUint8, ArrayToJSUint16, and ArrayToJSUint32, each element
 * in the array a) must be an integer; b) must be >= 0.  Integers
 * are clamped to fit in the destination size.  Only JSVAL_IS_INT values
 * are considered to be valid, so for JSUint32, the maximum value that
 * can be fast-converted is less than the full unsigned 32-bit range.
 *
 * For ArrayToJSInt8, ArrayToJSInt16, ArrayToJSInt32, each element in
 * the array must be an integer.  Integers are clamped to fit in the
 * destination size.  Only JSVAL_IS_INT values are considered to be
 * valid, so for JSInt32, the maximum value that can be
 * fast-converted is less than the full signed 32-bit range.
 * 
 * For ArrayToJSDouble, each element in the array must be an
 * integer -or- a double (JSVAL_IS_NUMBER).
 */

JS_FRIEND_API(JSBool)
js_ArrayToJSUint8Buffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                        JSUint8 *dest);

JS_FRIEND_API(JSBool)
js_ArrayToJSUint16Buffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                         JSUint16 *dest);

JS_FRIEND_API(JSBool)
js_ArrayToJSUint32Buffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                         JSUint32 *dest);

JS_FRIEND_API(JSBool)
js_ArrayToJSInt8Buffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                       JSInt8 *dest);

JS_FRIEND_API(JSBool)
js_ArrayToJSInt16Buffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                        JSInt16 *dest);

JS_FRIEND_API(JSBool)
js_ArrayToJSInt32Buffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                        JSInt32 *dest);

JS_FRIEND_API(JSBool)
js_ArrayToJSDoubleBuffer(JSContext *cx, JSObject *obj, jsuint offset, jsuint count,
                         jsdouble *dest);

JSBool
js_PrototypeHasIndexedProperties(JSContext *cx, JSObject *obj);

/*
 * Utility to access the value from the id returned by array_lookupProperty.
 */
JSBool
js_GetDenseArrayElementValue(JSContext *cx, JSObject *obj, JSProperty *prop,
                             jsval *vp);

JS_END_EXTERN_C

#endif /* jsarray_h___ */
1	/* -- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 --
2	*
3	* *** BEGIN LICENSE BLOCK ***
4	* Version: MPL 1.1/GPL 2.0/LGPL 2.1
5	*
6	* The contents of this file are subject to the Mozilla Public License Version
7	* 1.1 (the "License"); you may not use this file except in compliance with
8	* the License. You may obtain a copy of the License at
9	* http://www.mozilla.org/MPL/
10	*
11	* Software distributed under the License is distributed on an "AS IS" basis,
12	* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13	* for the specific language governing rights and limitations under the
14	* License.
15	*
16	* The Original Code is Mozilla Communicator client code, released
17	* March 31, 1998.
18	*
19	* The Initial Developer of the Original Code is
20	* Netscape Communications Corporation.
21	* Portions created by the Initial Developer are Copyright (C) 1998
22	* the Initial Developer. All Rights Reserved.
23	*
24	* Contributor(s):
25	*
26	* Alternatively, the contents of this file may be used under the terms of
27	* either of the GNU General Public License Version 2 or later (the "GPL"),
28	* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
29	* in which case the provisions of the GPL or the LGPL are applicable instead
30	* of those above. If you wish to allow use of your version of this file only
31	* under the terms of either the GPL or the LGPL, and not to allow others to
32	* use your version of this file under the terms of the MPL, indicate your
33	* decision by deleting the provisions above and replace them with the notice
34	* and other provisions required by the GPL or the LGPL. If you do not delete
35	* the provisions above, a recipient may use your version of this file under
36	* the terms of any one of the MPL, the GPL or the LGPL.
37	*
38	* *** END LICENSE BLOCK *** */
39
40	#ifndef jsarray_h___
41	#define jsarray_h___
42	/*
43	* JS Array interface.
44	*/
45	#include "jsprvtd.h"
46	#include "jspubtd.h"
47	#include "jsobj.h"
48
49	JS_BEGIN_EXTERN_C
50
51	#define ARRAY_CAPACITY_MIN 7
52
53	/* Generous sanity-bound on length (in elements) of array initialiser. */
54	#define ARRAY_INIT_LIMIT JS_BIT(24)
55
56	extern JSBool
57	js_IdIsIndex(jsval id, jsuint *indexp);
58
59	extern JSClass js_ArrayClass, js_SlowArrayClass;
60
61	#define OBJ_IS_DENSE_ARRAY(cx,obj) (OBJ_GET_CLASS(cx, obj) == &js_ArrayClass)
62
63	#define OBJ_IS_ARRAY(cx,obj) (OBJ_IS_DENSE_ARRAY(cx, obj) \|\| \
64	OBJ_GET_CLASS(cx, obj) == &js_SlowArrayClass)
65
66	/*
67	* Dense arrays are not native (OBJ_IS_NATIVE(cx, aobj) for a dense array aobj
68	* results in false, meaning aobj->map does not point to a JSScope).
69	*
70	* But Array methods are called via aobj.sort(), e.g., and the interpreter and
71	* the trace recorder must consult the property cache in order to perform well.
72	* The cache works only for native objects.
73	*
74	* Therefore the interpreter (js_Interpret in JSOP_GETPROP and JSOP_CALLPROP)
75	* and js_GetPropertyHelper use this inline function to skip up one link in the
76	* prototype chain when obj is a dense array, in order to find a native object
77	* (to wit, Array.prototype) in which to probe for cached methods.
78	*
79	* Note that setting aobj.__proto__ for a dense array aobj turns aobj into a
80	* slow array, avoiding the neede to skip.
81	*
82	* Callers of js_GetProtoIfDenseArray must take care to use the original object
83	* (obj) for the \|this\| value of a getter, setter, or method call (bug 476447).
84	*/
85	static JS_INLINE JSObject *
86	js_GetProtoIfDenseArray(JSContext cx, JSObject obj)
87	{
88	return OBJ_IS_DENSE_ARRAY(cx, obj) ? OBJ_GET_PROTO(cx, obj) : obj;
89	}
90
91	extern JSObject *
92	js_InitArrayClass(JSContext cx, JSObject obj);
93
94	extern JSObject *
95	js_NewArrayObject(JSContext cx, jsuint length, jsval vector,
96	JSBool holey = JS_FALSE);
97
98	/* Create an array object that starts out already made slow/sparse. */
99	extern JSObject *
100	js_NewSlowArrayObject(JSContext *cx);
101
102	extern JSBool
103	js_MakeArraySlow(JSContext cx, JSObject obj);
104
105	#define JSSLOT_ARRAY_LENGTH JSSLOT_PRIVATE
106	#define JSSLOT_ARRAY_COUNT (JSSLOT_ARRAY_LENGTH + 1)
107	#define JSSLOT_ARRAY_UNUSED (JSSLOT_ARRAY_COUNT + 1)
108
109	static JS_INLINE uint32
110	js_DenseArrayCapacity(JSObject *obj)
111	{
112	JS_ASSERT(OBJ_IS_DENSE_ARRAY(BOGUS_CX, obj));
113	return obj->dslots ? (uint32) obj->dslots[-1] : 0;
114	}
115
116	static JS_INLINE void
117	js_SetDenseArrayCapacity(JSObject *obj, uint32 capacity)
118	{
119	JS_ASSERT(OBJ_IS_DENSE_ARRAY(BOGUS_CX, obj));
120	JS_ASSERT(obj->dslots);
121	obj->dslots[-1] = (jsval) capacity;
122	}
123
124	extern JSBool
125	js_GetLengthProperty(JSContext cx, JSObject obj, jsuint *lengthp);
126
127	extern JSBool
128	js_SetLengthProperty(JSContext cx, JSObject obj, jsdouble length);
129
130	extern JSBool
131	js_HasLengthProperty(JSContext cx, JSObject obj, jsuint *lengthp);
132
133	extern JSBool JS_FASTCALL
134	js_IndexToId(JSContext cx, jsuint index, jsid idp);
135
136	/*
137	* Test whether an object is "array-like". Currently this means whether obj
138	* is an Array or an arguments object. We would like an API, and probably a
139	* way in the language, to bless other objects as array-like: having indexed
140	* properties, and a 'length' property of uint32 value equal to one more than
141	* the greatest index.
142	*/
143	extern JSBool
144	js_IsArrayLike(JSContext cx, JSObject obj, JSBool answerp, jsuint lengthp);
145
146	/*
147	* JS-specific merge sort function.
148	*/
149	typedef JSBool (JSComparator)(void arg, const void a, const void b,
150	int *result);
151	/*
152	* NB: vec is the array to be sorted, tmp is temporary space at least as big
153	* as vec. Both should be GC-rooted if appropriate.
154	*
155	* The sorted result is in vec. vec may be in an inconsistent state if the
156	* comparator function cmp returns an error inside a comparison, so remember
157	* to check the return value of this function.
158	*/
159	extern JS_REQUIRES_STACK JSBool
160	js_MergeSort(void *vec, size_t nel, size_t elsize, JSComparator cmp,
161	void arg, void tmp);
162
163	#ifdef DEBUG_ARRAYS
164	extern JSBool
165	js_ArrayInfo(JSContext cx, JSObject obj, uintN argc, jsval argv, jsval rval);
166	#endif
167
168	extern JSBool JS_FASTCALL
169	js_ArrayCompPush(JSContext cx, JSObject obj, jsval v);
170
171	/*
172	* Fast dense-array-to-buffer conversions.
173	*
174	* If the array is a dense array, fill [offset..offset+count] values
175	* into destination, assuming that types are consistent. Return
176	* JS_TRUE if successful, otherwise JS_FALSE -- note that the
177	* destination buffer may be modified even if JS_FALSE is returned
178	* (e.g. due to finding an inappropriate type later on in the array).
179	* If JS_FALSE is returned, no error conditions or exceptions are set
180	* on the context.
181	*
182	* For ArrayToJSUint8, ArrayToJSUint16, and ArrayToJSUint32, each element
183	* in the array a) must be an integer; b) must be >= 0. Integers
184	* are clamped to fit in the destination size. Only JSVAL_IS_INT values
185	* are considered to be valid, so for JSUint32, the maximum value that
186	* can be fast-converted is less than the full unsigned 32-bit range.
187	*
188	* For ArrayToJSInt8, ArrayToJSInt16, ArrayToJSInt32, each element in
189	* the array must be an integer. Integers are clamped to fit in the
190	* destination size. Only JSVAL_IS_INT values are considered to be
191	* valid, so for JSInt32, the maximum value that can be
192	* fast-converted is less than the full signed 32-bit range.
193	*
194	* For ArrayToJSDouble, each element in the array must be an
195	* integer -or- a double (JSVAL_IS_NUMBER).
196	*/
197
198	JS_FRIEND_API(JSBool)
199	js_ArrayToJSUint8Buffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
200	JSUint8 *dest);
201
202	JS_FRIEND_API(JSBool)
203	js_ArrayToJSUint16Buffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
204	JSUint16 *dest);
205
206	JS_FRIEND_API(JSBool)
207	js_ArrayToJSUint32Buffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
208	JSUint32 *dest);
209
210	JS_FRIEND_API(JSBool)
211	js_ArrayToJSInt8Buffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
212	JSInt8 *dest);
213
214	JS_FRIEND_API(JSBool)
215	js_ArrayToJSInt16Buffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
216	JSInt16 *dest);
217
218	JS_FRIEND_API(JSBool)
219	js_ArrayToJSInt32Buffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
220	JSInt32 *dest);
221
222	JS_FRIEND_API(JSBool)
223	js_ArrayToJSDoubleBuffer(JSContext cx, JSObject obj, jsuint offset, jsuint count,
224	jsdouble *dest);
225
226	JSBool
227	js_PrototypeHasIndexedProperties(JSContext cx, JSObject obj);
228
229	/*
230	* Utility to access the value from the id returned by array_lookupProperty.
231	*/
232	JSBool
233	js_GetDenseArrayElementValue(JSContext cx, JSObject obj, JSProperty *prop,
234	jsval *vp);
235
236	JS_END_EXTERN_C
237
238	#endif /* jsarray_h___ */