jsobj.c

来自「一个基于alice开发的机器人」· C语言 代码 · 共 2,081 行 · 第 1/5 页

        for (i = 0, length = ida->length; i < length; i++) {
            id = ida->vector[i];
#if JS_HAS_GETTER_SETTER
            ok = OBJ_LOOKUP_PROPERTY(cx, obj, id, &obj2, &prop);
            if (!ok)
                break;
            if (prop) {
                ok = OBJ_GET_ATTRIBUTES(cx, obj2, id, prop, &attrs);
                if (ok) {
                    if (OBJ_IS_NATIVE(obj2) &&
                        (attrs & (JSPROP_GETTER | JSPROP_SETTER))) {
                        val = JSVAL_NULL;
                        if (attrs & JSPROP_GETTER)
                            val = (jsval) ((JSScopeProperty*)prop)->getter;
                        if (attrs & JSPROP_SETTER) {
                            if (val != JSVAL_NULL) {
                                /* Mark the getter, then set val to setter. */
                                ok = (MarkSharpObjects(cx, JSVAL_TO_OBJECT(val),
                                                       NULL)
                                      != NULL);
                            }
                            val = (jsval) ((JSScopeProperty*)prop)->setter;
                        }
                    } else {
                        ok = OBJ_GET_PROPERTY(cx, obj, id, &val);
                    }
                }
                OBJ_DROP_PROPERTY(cx, obj2, prop);
            }
#else
            ok = OBJ_GET_PROPERTY(cx, obj, id, &val);
#endif
            if (!ok)
                break;
            if (!JSVAL_IS_PRIMITIVE(val) &&
                !MarkSharpObjects(cx, JSVAL_TO_OBJECT(val), NULL)) {
                ok = JS_FALSE;
                break;
            }
        }
        if (!ok || !idap)
            JS_DestroyIdArray(cx, ida);
        if (!ok)
            return NULL;
    } else {
        sharpid = (jsatomid) he->value;
        if (sharpid == 0) {
            sharpid = ++map->sharpgen << SHARP_ID_SHIFT;
            he->value = (void *) sharpid;
        }
        ida = NULL;
    }
    if (idap)
        *idap = ida;
    return he;
}

JSHashEntry *
js_EnterSharpObject(JSContext *cx, JSObject *obj, JSIdArray **idap,
                    jschar **sp)
{
    JSSharpObjectMap *map;
    JSHashTable *table;
    JSIdArray *ida;
    JSHashNumber hash;
    JSHashEntry *he, **hep;
    jsatomid sharpid;
    char buf[20];
    size_t len;

    /* Set to null in case we return an early error. */
    *sp = NULL;
    map = &cx->sharpObjectMap;
    table = map->table;
    if (!table) {
        table = JS_NewHashTable(8, js_hash_object, JS_CompareValues,
                                JS_CompareValues, NULL, NULL);
        if (!table) {
            JS_ReportOutOfMemory(cx);
            return NULL;
        }
        map->table = table;
    }

    ida = NULL;
    if (map->depth == 0) {
        he = MarkSharpObjects(cx, obj, &ida);
        if (!he)
            goto bad;
        JS_ASSERT((((jsatomid) he->value) & SHARP_BIT) == 0);
        if (!idap) {
            JS_DestroyIdArray(cx, ida);
            ida = NULL;
        }
    } else {
        hash = js_hash_object(obj);
        hep = JS_HashTableRawLookup(table, hash, obj);
        he = *hep;

        /*
         * It's possible that the value of a property has changed from the
         * first time the object's properties are traversed (when the property
         * ids are entered into the hash table) to the second (when they are
         * converted to strings), i.e., the OBJ_GET_PROPERTY() call is not
         * idempotent.
         */
        if (!he) {
            he = JS_HashTableRawAdd(table, hep, hash, obj, NULL);
            if (!he) {
                JS_ReportOutOfMemory(cx);
                goto bad;
            }
            *sp = NULL;
            sharpid = 0;
            goto out;
        }
    }

    sharpid = (jsatomid) he->value;
    if (sharpid == 0) {
        *sp = NULL;
    } else {
        len = JS_snprintf(buf, sizeof buf, "#%u%c",
                          sharpid >> SHARP_ID_SHIFT,
                          (sharpid & SHARP_BIT) ? '#' : '=');
        *sp = js_InflateString(cx, buf, len);
        if (!*sp) {
            if (ida)
                JS_DestroyIdArray(cx, ida);
            goto bad;
        }
    }

out:
    JS_ASSERT(he);
    if ((sharpid & SHARP_BIT) == 0) {
        if (idap && !ida) {
            ida = JS_Enumerate(cx, obj);
            if (!ida) {
                if (*sp) {
                    JS_free(cx, *sp);
                    *sp = NULL;
                }
                goto bad;
            }
        }
        map->depth++;
    }

    if (idap)
        *idap = ida;
    return he;

bad:
    /* Clean up the sharpObjectMap table on outermost error. */
    if (map->depth == 0) {
        map->sharpgen = 0;
        JS_HashTableDestroy(map->table);
        map->table = NULL;
    }
    return NULL;
}

void
js_LeaveSharpObject(JSContext *cx, JSIdArray **idap)
{
    JSSharpObjectMap *map;
    JSIdArray *ida;

    map = &cx->sharpObjectMap;
    JS_ASSERT(map->depth > 0);
    if (--map->depth == 0) {
        map->sharpgen = 0;
        JS_HashTableDestroy(map->table);
        map->table = NULL;
    }
    if (idap) {
        ida = *idap;
        if (ida) {
            JS_DestroyIdArray(cx, ida);
            *idap = NULL;
        }
    }
}

#define OBJ_TOSTRING_EXTRA      3       /* for 3 local GC roots */

#if JS_HAS_INITIALIZERS || JS_HAS_TOSOURCE
JSBool
js_obj_toSource(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
                jsval *rval)
{
    JSBool ok, outermost;
    JSHashEntry *he;
    JSIdArray *ida;
    jschar *chars, *ochars, *vsharp;
    const jschar *idstrchars, *vchars;
    size_t nchars, idstrlength, gsoplength, vlength, vsharplength;
    char *comma;
    jsint i, j, length, valcnt;
    jsid id;
#if JS_HAS_GETTER_SETTER
    JSObject *obj2;
    JSProperty *prop;
    uintN attrs;
#endif
    jsval val[2];
    JSString *gsop[2];
    JSAtom *atom;
    JSString *idstr, *valstr, *str;
    int stackDummy;

    if (!JS_CHECK_STACK_SIZE(cx, stackDummy)) {
        JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_OVER_RECURSED);
        return JS_FALSE;
    }

    /*
     * obj_toString for 1.2 calls toSource, and doesn't want the extra parens
     * on the outside.
     */
    outermost = (cx->version != JSVERSION_1_2 && cx->sharpObjectMap.depth == 0);
    he = js_EnterSharpObject(cx, obj, &ida, &chars);
    if (!he)
        return JS_FALSE;
    if (IS_SHARP(he)) {
        /*
         * We didn't enter -- obj is already "sharp", meaning we've visited it
         * already in our depth first search, and therefore chars contains a
         * string of the form "#n#".
         */
        JS_ASSERT(!ida);
#if JS_HAS_SHARP_VARS
        nchars = js_strlen(chars);
#else
        chars[0] = '{';
        chars[1] = '}';
        chars[2] = 0;
        nchars = 2;
#endif
        goto make_string;
    }
    JS_ASSERT(ida);
    ok = JS_TRUE;

    if (!chars) {
        /* If outermost, allocate 4 + 1 for "({})" and the terminator. */
        chars = (jschar *) malloc(((outermost ? 4 : 2) + 1) * sizeof(jschar));
        nchars = 0;
        if (!chars)
            goto error;
        if (outermost)
            chars[nchars++] = '(';
    } else {
        /* js_EnterSharpObject returned a string of the form "#n=" in chars. */
        MAKE_SHARP(he);
        nchars = js_strlen(chars);
        chars = (jschar *)
            realloc((ochars = chars), (nchars + 2 + 1) * sizeof(jschar));
        if (!chars) {
            free(ochars);
            goto error;
        }
        if (outermost) {
            /*
             * No need for parentheses around the whole shebang, because #n=
             * unambiguously begins an object initializer, and never a block
             * statement.
             */
            outermost = JS_FALSE;
        }
    }

    chars[nchars++] = '{';

    comma = NULL;

    for (i = 0, length = ida->length; i < length; i++) {
        /* Get strings for id and value and GC-root them via argv. */
        id = ida->vector[i];

#if JS_HAS_GETTER_SETTER

        ok = OBJ_LOOKUP_PROPERTY(cx, obj, id, &obj2, &prop);
        if (!ok)
            goto error;
        valcnt = 0;
        if (prop) {
            ok = OBJ_GET_ATTRIBUTES(cx, obj2, id, prop, &attrs);
            if (!ok) {
                OBJ_DROP_PROPERTY(cx, obj2, prop);
                goto error;
            }
            if (OBJ_IS_NATIVE(obj2) &&
                (attrs & (JSPROP_GETTER | JSPROP_SETTER))) {
                if (attrs & JSPROP_GETTER) {
                    val[valcnt] = (jsval) ((JSScopeProperty *)prop)->getter;
#ifdef OLD_GETTER_SETTER
                    gsop[valcnt] =
                        ATOM_TO_STRING(cx->runtime->atomState.getterAtom);
#else
                    gsop[valcnt] =
                        ATOM_TO_STRING(cx->runtime->atomState.getAtom);
#endif
                    valcnt++;
                }
                if (attrs & JSPROP_SETTER) {
                    val[valcnt] = (jsval) ((JSScopeProperty *)prop)->setter;
#ifdef OLD_GETTER_SETTER
                    gsop[valcnt] =
                        ATOM_TO_STRING(cx->runtime->atomState.setterAtom);
#else
                    gsop[valcnt] =
                        ATOM_TO_STRING(cx->runtime->atomState.setAtom);
#endif
                    valcnt++;
                }
            } else {
                valcnt = 1;
                gsop[0] = NULL;
                ok = OBJ_GET_PROPERTY(cx, obj, id, &val[0]);
            }
            OBJ_DROP_PROPERTY(cx, obj2, prop);
        }

#else  /* !JS_HAS_GETTER_SETTER */

        valcnt = 1;
        gsop[0] = NULL;
        ok = OBJ_GET_PROPERTY(cx, obj, id, &val[0]);

#endif /* !JS_HAS_GETTER_SETTER */

        if (!ok)
            goto error;

        /* Convert id to a jsval and then to a string. */
        atom = JSVAL_IS_INT(id) ? NULL : (JSAtom *)id;
        id = ID_TO_VALUE(id);
        idstr = js_ValueToString(cx, id);
        if (!idstr) {
            ok = JS_FALSE;
            goto error;
        }
        argv[0] = STRING_TO_JSVAL(idstr);

        /*
         * If id is a string that's a reserved identifier, or else id is not
         * an identifier at all, then it needs to be quoted.
         */
        if (atom && (ATOM_KEYWORD(atom) || !js_IsIdentifier(idstr))) {
            idstr = js_QuoteString(cx, idstr, (jschar)'\'');
            if (!idstr) {
                ok = JS_FALSE;
                goto error;
            }
            argv[0] = STRING_TO_JSVAL(idstr);
        }
        idstrchars = JSSTRING_CHARS(idstr);
        idstrlength = JSSTRING_LENGTH(idstr);

        for (j = 0; j < valcnt; j++) {
            /* Convert val[j] to its canonical source form. */
            valstr = js_ValueToSource(cx, val[j]);
            if (!valstr) {
                ok = JS_FALSE;
                goto error;
            }
            argv[1+j] = STRING_TO_JSVAL(valstr);
            vchars = JSSTRING_CHARS(valstr);
            vlength = JSSTRING_LENGTH(valstr);

#ifndef OLD_GETTER_SETTER
            /* Remove 'function ' from beginning of valstr. */
            if (gsop[j]) {
                int n = strlen(js_function_str) + 1;
                vchars += n;
                vlength -= n;
            }
#endif

            /* If val[j] is a non-sharp object, consider sharpening it. */
            vsharp = NULL;
            vsharplength = 0;
#if JS_HAS_SHARP_VARS
            if (!JSVAL_IS_PRIMITIVE(val[j]) && vchars[0] != '#') {
                he = js_EnterSharpObject(cx, JSVAL_TO_OBJECT(val[j]), NULL,
                                         &vsharp);
                if (!he) {
                    ok = JS_FALSE;
                    goto error;
                }
                if (IS_SHARP(he)) {
                    vchars = vsharp;
                    vlength = js_strlen(vchars);
                } else {
                    if (vsharp) {
                        vsharplength = js_strlen(vsharp);
                        MAKE_SHARP(he);
                    }
                    js_LeaveSharpObject(cx, NULL);
                }
            }
#endif

            /* Allocate 1 + 1 at end for closing brace and terminating 0. */
            chars = (jschar *)
                realloc((ochars = chars),
                        (nchars + (comma ? 2 : 0) +
                         idstrlength + 1 +
                         (gsop[j] ? 1 + JSSTRING_LENGTH(gsop[j]) : 0) +
                         vsharplength + vlength +
                         (outermost ? 2 : 1) + 1) * sizeof(jschar));
            if (!chars) {
                /* Save code space on error: let JS_free ignore null vsharp. */
                JS_free(cx, vsharp);
                free(ochars);