jsj_javaobject.c

caffeine-monkey java实现的js模拟引擎

    JSJPropertyInfo prop_info;
    JSBool result;

    /* printf("In JavaObject_setProperty\n"); */

    /* Get the Java per-thread environment pointer for this JSContext */
    jsj_env = jsj_EnterJava(cx, &jEnv);
    if (!jEnv)
        return JS_FALSE;

    prop_info.wantProp = JS_FALSE;
    if (!lookup_member_by_id(cx, jEnv, obj, &java_wrapper, id, &member_descriptor, NULL,
                             &proto_chain, &prop_info)) {
        jsj_ExitJava(jsj_env);
        return JS_FALSE;
    }

    /* Could be assignment to magic JS __proto__ property rather than a Java field */
    if (!member_descriptor) {
        if (proto_chain && (prop_info.attributes & JSPROP_SHARED)) {
            JS_SetProperty(cx, proto_chain, prop_info.name, vp);
        } else {
            JS_IdToValue(cx, id, &idval);
            if (!JSVAL_IS_STRING(idval))
                goto no_such_field;
            member_name = JS_GetStringBytes(JSVAL_TO_STRING(idval));
            if (strcmp(member_name, "__proto__"))
                goto no_such_field;
            if (!JSVAL_IS_OBJECT(*vp)) {
                JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                                     JSJMSG_BAD_PROTO_ASSIGNMENT);
                jsj_ExitJava(jsj_env);
                return JS_FALSE;
            }
            JS_SetPrototype(cx, obj, JSVAL_TO_OBJECT(*vp));
        }
        jsj_ExitJava(jsj_env);
        return JS_TRUE;
    }

    /* Check for the case where there is a method with the given name, but no field
       with that name */
    if (!member_descriptor->field)
        goto no_such_field;

    /* Silently fail if field value is final (immutable), as required by ECMA spec */
    if (member_descriptor->field->modifiers & ACC_FINAL) {
        jsj_ExitJava(jsj_env);
        return JS_TRUE;
    }

    java_obj = java_wrapper->java_obj;

    if (jaApplet && (*jEnv)->IsInstanceOf(jEnv, java_obj, jaApplet)) {
        jsj_JSIsCallingApplet = JS_TRUE;
    }

    result = jsj_SetJavaFieldValue(cx, jEnv, member_descriptor->field, java_obj, *vp);
    jsj_ExitJava(jsj_env);
    return result;

no_such_field:
    JS_IdToValue(cx, id, &idval);
    member_name = JS_GetStringBytes(JSVAL_TO_STRING(idval));
    class_descriptor = java_wrapper->class_descriptor;
    JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                         JSJMSG_NO_NAME_IN_CLASS,
                         member_name, class_descriptor->name);
    jsj_ExitJava(jsj_env);
    return JS_FALSE;
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_lookupProperty(JSContext *cx, JSObject *obj, jsid id,
                         JSObject **objp, JSProperty **propp)
{
    JNIEnv *jEnv;
    JSErrorReporter old_reporter;
    jsval dummy_val;
    JSObject *proto_chain;
    JSJPropertyInfo prop_info;
    JSJavaThreadState *jsj_env;

    /* printf("In JavaObject_lookupProperty()\n"); */

    /* Get the Java per-thread environment pointer for this JSContext */
    jsj_env = jsj_EnterJava(cx, &jEnv);
    if (!jEnv)
        return JS_FALSE;

    old_reporter = JS_SetErrorReporter(cx, NULL);
    prop_info.wantProp = JS_TRUE;
    if (lookup_member_by_id(cx, jEnv, obj, NULL, id, NULL, &dummy_val,
                            &proto_chain, &prop_info)) {
        /* signify that the property is in the prototype chain or the object itself. */
        if (proto_chain) {
            *objp = proto_chain;
            *propp = prop_info.prop;
        } else {
            *objp = obj;
            *propp = (JSProperty*)1;
        }
    } else {
        *objp = NULL;
        *propp = NULL;
    }

    JS_SetErrorReporter(cx, old_reporter);
    jsj_ExitJava(jsj_env);
    return JS_TRUE;
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_defineProperty(JSContext *cx, JSObject *obj, jsid id, jsval value,
                         JSPropertyOp getter, JSPropertyOp setter,
                         uintN attrs, JSProperty **propp)
{
    JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                         JSJMSG_JOBJECT_PROP_DEFINE);
    return JS_FALSE;
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_getAttributes(JSContext *cx, JSObject *obj, jsid id,
                        JSProperty *prop, uintN *attrsp)
{
    /* We don't maintain JS property attributes for Java class members */
    *attrsp = JSPROP_PERMANENT|JSPROP_ENUMERATE;
    return JS_TRUE;
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_setAttributes(JSContext *cx, JSObject *obj, jsid id,
                        JSProperty *prop, uintN *attrsp)
{
    /* We don't maintain JS property attributes for Java class members */
    if (*attrsp != (JSPROP_PERMANENT|JSPROP_ENUMERATE)) {
        JS_ASSERT(0);
        return JS_FALSE;
    }

    /* Silently ignore all setAttribute attempts */
    return JS_TRUE;
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_deleteProperty(JSContext *cx, JSObject *obj, jsid id, jsval *vp)
{
    JSVersion version = JS_GetVersion(cx);

    *vp = JSVAL_FALSE;

    if (!JSVERSION_IS_ECMA(version)) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                                        JSJMSG_JOBJECT_PROP_DELETE);
        return JS_FALSE;
    } else {
        /* Attempts to delete permanent properties are silently ignored
           by ECMAScript. */
        return JS_TRUE;
    }
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_defaultValue(JSContext *cx, JSObject *obj, JSType type, jsval *vp)
{
    /* printf("In JavaObject_defaultValue()\n"); */
    return JavaObject_convert(cx, obj, type, vp);
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_newEnumerate(JSContext *cx, JSObject *obj, JSIterateOp enum_op,
                        jsval *statep, jsid *idp)
{
    JavaObjectWrapper *java_wrapper;
    JavaMemberDescriptor *member_descriptor;
    JavaClassDescriptor *class_descriptor;
    JNIEnv *jEnv;
    JSJavaThreadState *jsj_env;

    java_wrapper = JS_GetPrivate(cx, obj);
    /* Check for prototype object */
    if (!java_wrapper) {
        *statep = JSVAL_NULL;
        if (idp)
            *idp = INT_TO_JSVAL(0);
        return JS_TRUE;
    }

    class_descriptor = java_wrapper->class_descriptor;

    switch(enum_op) {
    case JSENUMERATE_INIT:

        /* Get the Java per-thread environment pointer for this JSContext */
        jsj_env = jsj_EnterJava(cx, &jEnv);
        if (!jEnv)
            return JS_FALSE;

        member_descriptor = jsj_GetClassInstanceMembers(cx, jEnv, class_descriptor);
        *statep = PRIVATE_TO_JSVAL(member_descriptor);
        if (idp)
            *idp = INT_TO_JSVAL(class_descriptor->num_instance_members);
        jsj_ExitJava(jsj_env);
        return JS_TRUE;

    case JSENUMERATE_NEXT:
        member_descriptor = JSVAL_TO_PRIVATE(*statep);
        if (member_descriptor) {

            /* Don't enumerate explicit-signature methods, i.e. enumerate toValue,
               but not toValue(int), toValue(double), etc. */
            while (member_descriptor->methods && member_descriptor->methods->is_alias) {
                member_descriptor = member_descriptor->next;
                if (!member_descriptor) {
                    *statep = JSVAL_NULL;
                    return JS_TRUE;
                }
            }

            *idp = member_descriptor->id;
            *statep = PRIVATE_TO_JSVAL(member_descriptor->next);
            return JS_TRUE;
        }

        /* Fall through ... */

    case JSENUMERATE_DESTROY:
        *statep = JSVAL_NULL;
        return JS_TRUE;

    default:
        JS_ASSERT(0);
        return JS_FALSE;
    }
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaObject_checkAccess(JSContext *cx, JSObject *obj, jsid id,
                      JSAccessMode mode, jsval *vp, uintN *attrsp)
{
    switch (mode) {
    case JSACC_WATCH:
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                             JSJMSG_JOBJECT_PROP_WATCH);
        return JS_FALSE;

    case JSACC_IMPORT:
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                             JSJMSG_JOBJECT_PROP_EXPORT);
        return JS_FALSE;

    default:
        return JS_TRUE;
    }
}

#define JSJ_SLOT_COUNT (JSSLOT_PRIVATE+1)

JSObjectMap * JS_DLL_CALLBACK
jsj_wrapper_newObjectMap(JSContext *cx, jsrefcount nrefs, JSObjectOps *ops,
                         JSClass *clasp, JSObject *obj)
{
    JSObjectMap * map;

    map = (JSObjectMap *) JS_malloc(cx, sizeof(JSObjectMap));
    if (map) {
        map->nrefs = nrefs;
        map->ops = ops;
        map->nslots = JSJ_SLOT_COUNT;
        map->freeslot = JSJ_SLOT_COUNT;
    }
    return map;
}

void JS_DLL_CALLBACK
jsj_wrapper_destroyObjectMap(JSContext *cx, JSObjectMap *map)
{
    JS_free(cx, map);
}

jsval JS_DLL_CALLBACK
jsj_wrapper_getRequiredSlot(JSContext *cx, JSObject *obj, uint32 slot)
{
    JS_ASSERT(slot < JSJ_SLOT_COUNT);
    JS_ASSERT(obj->slots);
    JS_ASSERT(obj->map->nslots == JSJ_SLOT_COUNT);
    JS_ASSERT(obj->map->freeslot == JSJ_SLOT_COUNT);
    return obj->slots[slot];
}

JSBool JS_DLL_CALLBACK
jsj_wrapper_setRequiredSlot(JSContext *cx, JSObject *obj, uint32 slot, jsval v)
{
    JS_ASSERT(slot < JSJ_SLOT_COUNT);
    JS_ASSERT(obj->slots);
    JS_ASSERT(obj->map->nslots == JSJ_SLOT_COUNT);
    JS_ASSERT(obj->map->freeslot == JSJ_SLOT_COUNT);
    obj->slots[slot] = v;
    return JS_TRUE;
}

JSObjectOps JavaObject_ops = {
    /* Mandatory non-null function pointer members. */
    jsj_wrapper_newObjectMap,       /* newObjectMap */
    jsj_wrapper_destroyObjectMap,   /* destroyObjectMap */
    JavaObject_lookupProperty,
    JavaObject_defineProperty,
    JavaObject_getPropertyById,     /* getProperty */
    JavaObject_setPropertyById,     /* setProperty */
    JavaObject_getAttributes,
    JavaObject_setAttributes,
    JavaObject_deleteProperty,
    JavaObject_defaultValue,
    JavaObject_newEnumerate,
    JavaObject_checkAccess,

    /* Optionally non-null members start here. */
    NULL,                           /* thisObject */
    NULL,                           /* dropProperty */
    NULL,                           /* call */
    NULL,                           /* construct */
    NULL,                           /* xdrObject */
    NULL,                           /* hasInstance */
    NULL,                           /* setProto */
    NULL,                           /* setParent */
    NULL,                           /* mark */
    NULL,                           /* clear */
    jsj_wrapper_getRequiredSlot,    /* getRequiredSlot */
    jsj_wrapper_setRequiredSlot     /* setRequiredSlot */
};

JS_STATIC_DLL_CALLBACK(JSObjectOps *)
JavaObject_getObjectOps(JSContext *cx, JSClass *clazz)
{
    return &JavaObject_ops;
}

JSClass JavaObject_class = {
    "JavaObject", JSCLASS_HAS_PRIVATE,
    NULL, NULL, NULL, NULL,
    NULL, NULL, JavaObject_convert, JavaObject_finalize,

    /* Optionally non-null members start here. */
    JavaObject_getObjectOps,
    NULL,                       /* checkAccess */
    NULL,                       /* call */
    NULL,                       /* construct */
    NULL,                       /* xdrObject */
    NULL,                       /* hasInstance */
    NULL,                       /* mark */
    0,                          /* spare */
};

extern JS_IMPORT_DATA(JSObjectOps) js_ObjectOps;

JSBool
jsj_init_JavaObject(JSContext *cx, JSObject *global_obj)
{
    return JS_InitClass(cx, global_obj,
                        0, &JavaObject_class, 0, 0,
                        0, 0,
                        0, 0) != 0;
}