gecko/js/src/jsiter.h

213 lines
7.1 KiB
C

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sw=4 et tw=78:
*
* ***** 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 jsiter_h___
#define jsiter_h___
/*
* JavaScript iterators.
*/
#include "jsprvtd.h"
#include "jspubtd.h"
#include "jsversion.h"
JS_BEGIN_EXTERN_C
/*
* NB: these flag bits are encoded into the bytecode stream in the immediate
* operand of JSOP_ITER, so don't change them without advancing jsxdrapi.h's
* JSXDR_BYTECODE_VERSION.
*/
#define JSITER_ENUMERATE 0x1 /* for-in compatible hidden default iterator */
#define JSITER_FOREACH 0x2 /* return [key, value] pair rather than key */
#define JSITER_KEYVALUE 0x4 /* destructuring for-in wants [key, value] */
#define JSITER_OWNONLY 0x8 /* iterate over obj's own properties only */
#define JSITER_HIDDEN 0x10 /* also enumerate non-enumerable properties */
struct NativeIterator {
JSObject *obj;
jsval *props_array;
jsval *props_cursor;
jsval *props_end;
uint32 *shapes_array;
uint32 shapes_length;
uint32 shapes_key;
uintN flags;
JSObject *next;
static NativeIterator *allocate(JSContext *cx, JSObject *obj, uintN flags,
uint32 *sarray, uint32 slength, uint32 key,
jsval *parray, uint32 plength);
void mark(JSTracer *trc);
};
/*
* Magic jsval that indicates that a custom enumerate hook forwarded
* to js_Enumerate, which really means the object can be enumerated like
* a native object.
*/
static const jsval JSVAL_NATIVE_ENUMERATE_COOKIE = SPECIAL_TO_JSVAL(0x220576);
bool
GetPropertyNames(JSContext *cx, JSObject *obj, uintN flags, JSIdArray **idap);
bool
GetIterator(JSContext *cx, JSObject *obj, uintN flags, jsval *vp);
bool
JSIdArrayToIterator(JSContext *cx, JSObject *obj, uintN flags, JSIdArray *ida, jsval *vp);
/*
* Convert the value stored in *vp to its iteration object. The flags should
* contain JSITER_ENUMERATE if js_ValueToIterator is called when enumerating
* for-in semantics are required, and when the caller can guarantee that the
* iterator will never be exposed to scripts.
*/
extern JS_FRIEND_API(JSBool)
js_ValueToIterator(JSContext *cx, uintN flags, jsval *vp);
extern JS_FRIEND_API(JSBool)
js_CloseIterator(JSContext *cx, jsval v);
bool
js_SuppressDeletedProperty(JSContext *cx, JSObject *obj, jsid id);
/*
* IteratorMore() indicates whether another value is available. It might
* internally call iterobj.next() and then cache the value until its
* picked up by IteratorNext(). The value is cached in the current context.
*/
extern JSBool
js_IteratorMore(JSContext *cx, JSObject *iterobj, jsval *rval);
extern JSBool
js_IteratorNext(JSContext *cx, JSObject *iterobj, jsval *rval);
extern JSBool
js_ThrowStopIteration(JSContext *cx);
#if JS_HAS_GENERATORS
/*
* Generator state codes.
*/
typedef enum JSGeneratorState {
JSGEN_NEWBORN, /* not yet started */
JSGEN_OPEN, /* started by a .next() or .send(undefined) call */
JSGEN_RUNNING, /* currently executing via .next(), etc., call */
JSGEN_CLOSING, /* close method is doing asynchronous return */
JSGEN_CLOSED /* closed, cannot be started or closed again */
} JSGeneratorState;
struct JSGenerator {
JSObject *obj;
JSGeneratorState state;
JSFrameRegs savedRegs;
uintN vplen;
JSStackFrame *liveFrame;
JSObject *enumerators;
jsval floatingStack[1];
JSStackFrame *getFloatingFrame() {
return reinterpret_cast<JSStackFrame *>(floatingStack + vplen);
}
JSStackFrame *getLiveFrame() {
JS_ASSERT((state == JSGEN_RUNNING || state == JSGEN_CLOSING) ==
(liveFrame != getFloatingFrame()));
return liveFrame;
}
};
extern JSObject *
js_NewGenerator(JSContext *cx);
/*
* Generator stack frames do not have stable pointers since they get copied to
* and from the generator object and the stack (see SendToGenerator). This is a
* problem for Block and With objects, which need to store a pointer to the
* enclosing stack frame. The solution is for Block and With objects to store
* a pointer to the "floating" stack frame stored in the generator object,
* since it is stable, and maintain, in the generator object, a pointer to the
* "live" stack frame (either a copy on the stack or the floating frame). Thus,
* Block and With objects must "normalize" to and from the floating/live frames
* in the case of generators using the following functions.
*/
inline JSStackFrame *
js_FloatingFrameIfGenerator(JSContext *cx, JSStackFrame *fp)
{
JS_ASSERT(cx->stack().contains(fp));
if (JS_UNLIKELY(fp->isGenerator()))
return cx->generatorFor(fp)->getFloatingFrame();
return fp;
}
/* Given a floating frame, given the JSGenerator containing it. */
extern JSGenerator *
js_FloatingFrameToGenerator(JSStackFrame *fp);
inline JSStackFrame *
js_LiveFrameIfGenerator(JSStackFrame *fp)
{
if (fp->flags & JSFRAME_GENERATOR)
return js_FloatingFrameToGenerator(fp)->getLiveFrame();
return fp;
}
#endif
extern JSExtendedClass js_GeneratorClass;
extern JSExtendedClass js_IteratorClass;
extern JSClass js_StopIterationClass;
static inline bool
js_ValueIsStopIteration(jsval v)
{
return !JSVAL_IS_PRIMITIVE(v) &&
JSVAL_TO_OBJECT(v)->getClass() == &js_StopIterationClass;
}
extern JSObject *
js_InitIteratorClasses(JSContext *cx, JSObject *obj);
JS_END_EXTERN_C
#endif /* jsiter_h___ */