jsinterp.c

来自「java script test programing source code」· C语言 代码 · 共 1,863 行 · 第 1/5 页

     * parameters.
     */
    if (JSVAL_IS_PRIMITIVE(v)) {
#if JS_HAS_NO_SUCH_METHOD
        if (fp->script && !(flags & JSINVOKE_INTERNAL)) {
            ok = NoSuchMethod(cx, fp, vp, flags, argc);
            if (ok)
                frame.rval = *vp;
            goto out2;
        }
#endif
        goto bad;
    }

    /* Load thisv after potentially calling NoSuchMethod, which may set it. */
    thisv = vp[1];

    funobj = JSVAL_TO_OBJECT(v);
    parent = OBJ_GET_PARENT(cx, funobj);
    clasp = OBJ_GET_CLASS(cx, funobj);
    if (clasp != &js_FunctionClass) {
        /* Function is inlined, all other classes use object ops. */
        ops = funobj->map->ops;

        /*
         * XXX this makes no sense -- why convert to function if clasp->call?
         * XXX better to call that hook without converting
         * XXX the only thing that needs fixing is liveconnect
         *
         * Try converting to function, for closure and API compatibility.
         * We attempt the conversion under all circumstances for 1.2, but
         * only if there is a call op defined otherwise.
         */
        if ((ops == &js_ObjectOps) ? clasp->call : ops->call) {
            ok = clasp->convert(cx, funobj, JSTYPE_FUNCTION, &v);
            if (!ok)
                goto out2;

            if (VALUE_IS_FUNCTION(cx, v)) {
                /* Make vp refer to funobj to keep it available as argv[-2]. */
                *vp = v;
                funobj = JSVAL_TO_OBJECT(v);
                parent = OBJ_GET_PARENT(cx, funobj);
                goto have_fun;
            }
        }
        fun = NULL;
        script = NULL;
        nslots = nvars = 0;

        /* Try a call or construct native object op. */
        native = (flags & JSINVOKE_CONSTRUCT) ? ops->construct : ops->call;
        if (!native)
            goto bad;

        if (JSVAL_IS_OBJECT(thisv)) {
            thisp = JSVAL_TO_OBJECT(thisv);
        } else {
            PRIMITIVE_TO_OBJECT(cx, thisv, thisp);
            if (!thisp)
                goto out2;
            vp[1] = thisv = OBJECT_TO_JSVAL(thisp);
        }
    } else {
have_fun:
        /* Get private data and set derived locals from it. */
        fun = (JSFunction *) JS_GetPrivate(cx, funobj);
        nslots = (fun->nargs > argc) ? fun->nargs - argc : 0;
        if (FUN_INTERPRETED(fun)) {
            native = NULL;
            script = fun->u.i.script;
            nvars = fun->u.i.nvars;
        } else {
            native = fun->u.n.native;
            script = NULL;
            nvars = 0;
            nslots += fun->u.n.extra;
        }

        if (JSFUN_BOUND_METHOD_TEST(fun->flags)) {
            /* Handle bound method special case. */
            thisp = parent;
        } else if (JSVAL_IS_OBJECT(thisv)) {
            thisp = JSVAL_TO_OBJECT(thisv);
        } else {
            uintN thispflags = JSFUN_THISP_FLAGS(fun->flags);

            JS_ASSERT(!(flags & JSINVOKE_CONSTRUCT));
            if (JSVAL_IS_STRING(thisv)) {
                if (JSFUN_THISP_TEST(thispflags, JSFUN_THISP_STRING)) {
                    thisp = (JSObject *) thisv;
                    goto init_frame;
                }
                thisp = js_StringToObject(cx, JSVAL_TO_STRING(thisv));
            } else if (JSVAL_IS_INT(thisv)) {
                if (JSFUN_THISP_TEST(thispflags, JSFUN_THISP_NUMBER)) {
                    thisp = (JSObject *) thisv;
                    goto init_frame;
                }
                thisp = js_NumberToObject(cx, (jsdouble)JSVAL_TO_INT(thisv));
            } else if (JSVAL_IS_DOUBLE(thisv)) {
                if (JSFUN_THISP_TEST(thispflags, JSFUN_THISP_NUMBER)) {
                    thisp = (JSObject *) thisv;
                    goto init_frame;
                }
                thisp = js_NumberToObject(cx, *JSVAL_TO_DOUBLE(thisv));
            } else {
                JS_ASSERT(JSVAL_IS_BOOLEAN(thisv));
                if (JSFUN_THISP_TEST(thispflags, JSFUN_THISP_BOOLEAN)) {
                    thisp = (JSObject *) thisv;
                    goto init_frame;
                }
                thisp = js_BooleanToObject(cx, JSVAL_TO_BOOLEAN(thisv));
            }
            if (!thisp) {
                ok = JS_FALSE;
                goto out2;
            }
            goto init_frame;
        }
    }

    if (flags & JSINVOKE_CONSTRUCT) {
        /* Default return value for a constructor is the new object. */
        frame.rval = OBJECT_TO_JSVAL(thisp);
    } else {
        thisp = js_ComputeThis(cx, thisp, vp + 2);
        if (!thisp) {
            ok = JS_FALSE;
            goto out2;
        }
    }

  init_frame:
    /* Initialize the rest of frame, except for sp (set by SAVE_SP later). */
    frame.thisp = thisp;
    frame.varobj = NULL;
    frame.callobj = frame.argsobj = NULL;
    frame.script = script;
    frame.fun = fun;
    frame.argc = argc;
    frame.argv = sp - argc;
    frame.nvars = nvars;
    frame.vars = sp;
    frame.down = fp;
    frame.annotation = NULL;
    frame.scopeChain = NULL;    /* set below for real, after cx->fp is set */
    frame.pc = NULL;
    frame.spbase = NULL;
    frame.sharpDepth = 0;
    frame.sharpArray = NULL;
    frame.flags = flags;
    frame.dormantNext = NULL;
    frame.xmlNamespace = NULL;
    frame.blockChain = NULL;

    /* From here on, control must flow through label out: to return. */
    cx->fp = &frame;

    /* Init these now in case we goto out before first hook call. */
    hook = cx->runtime->callHook;
    hookData = NULL;

    /* Check for argument slots required by the function. */
    if (nslots) {
        /* All arguments must be contiguous, so we may have to copy actuals. */
        nalloc = nslots;
        limit = (jsval *) cx->stackPool.current->limit;
        JS_ASSERT((jsval *) cx->stackPool.current->base <= sp && sp <= limit);
        if (sp + nslots > limit) {
            /* Hit end of arena: we have to copy argv[-2..(argc+nslots-1)]. */
            nalloc += 2 + argc;
        } else {
            /* Take advantage of surplus slots in the caller's frame depth. */
            JS_ASSERT((jsval *)mark >= sp);
            surplus = (jsval *)mark - sp;
            nalloc -= surplus;
        }

        /* Check whether we have enough space in the caller's frame. */
        if ((intN)nalloc > 0) {
            /* Need space for actuals plus missing formals minus surplus. */
            newsp = js_AllocRawStack(cx, nalloc, NULL);
            if (!newsp) {
                ok = JS_FALSE;
                goto out;
            }

            /* If we couldn't allocate contiguous args, copy actuals now. */
            if (newsp != mark) {
                JS_ASSERT(sp + nslots > limit);
                JS_ASSERT(2 + argc + nslots == nalloc);
                *newsp++ = vp[0];
                *newsp++ = vp[1];
                if (argc)
                    memcpy(newsp, frame.argv, argc * sizeof(jsval));
                frame.argv = newsp;
                sp = frame.vars = newsp + argc;
            }
        }

        /* Advance frame.vars to make room for the missing args. */
        frame.vars += nslots;

        /* Push void to initialize missing args. */
        do {
            PUSH(JSVAL_VOID);
        } while (--nslots != 0);
    }
    JS_ASSERT(nslots == 0);

    /* Now allocate stack space for local variables. */
    if (nvars) {
        JS_ASSERT((jsval *)cx->stackPool.current->avail >= frame.vars);
        surplus = (jsval *)cx->stackPool.current->avail - frame.vars;
        if (surplus < nvars) {
            newsp = js_AllocRawStack(cx, nvars, NULL);
            if (!newsp) {
                ok = JS_FALSE;
                goto out;
            }
            if (newsp != sp) {
                /* NB: Discontinuity between argv and vars. */
                sp = frame.vars = newsp;
            }
        }

        /* Push void to initialize local variables. */
        do {
            PUSH(JSVAL_VOID);
        } while (--nvars != 0);
    }
    JS_ASSERT(nvars == 0);

    /* Store the current sp in frame before calling fun. */
    SAVE_SP(&frame);

    /* call the hook if present */
    if (hook && (native || script))
        hookData = hook(cx, &frame, JS_TRUE, 0, cx->runtime->callHookData);

    /* Call the function, either a native method or an interpreted script. */
    if (native) {
#ifdef DEBUG_NOT_THROWING
        JSBool alreadyThrowing = cx->throwing;
#endif

#if JS_HAS_LVALUE_RETURN
        /* Set by JS_SetCallReturnValue2, used to return reference types. */
        cx->rval2set = JS_FALSE;
#endif

        /* If native, use caller varobj and scopeChain for eval. */
        frame.varobj = fp->varobj;
        frame.scopeChain = fp->scopeChain;
        ok = native(cx, frame.thisp, argc, frame.argv, &frame.rval);
        JS_RUNTIME_METER(cx->runtime, nativeCalls);
#ifdef DEBUG_NOT_THROWING
        if (ok && !alreadyThrowing)
            ASSERT_NOT_THROWING(cx);
#endif
    } else if (script) {
#ifdef DUMP_CALL_TABLE
        LogCall(cx, *vp, argc, frame.argv);
#endif
        /* Use parent scope so js_GetCallObject can find the right "Call". */
        frame.scopeChain = parent;
        if (JSFUN_HEAVYWEIGHT_TEST(fun->flags)) {
            /* Scope with a call object parented by the callee's parent. */
            if (!js_GetCallObject(cx, &frame, parent)) {
                ok = JS_FALSE;
                goto out;
            }
        }
        ok = js_Interpret(cx, script->code, &v);
    } else {
        /* fun might be onerror trying to report a syntax error in itself. */
        frame.scopeChain = NULL;
        ok = JS_TRUE;
    }

out:
    if (hookData) {
        hook = cx->runtime->callHook;
        if (hook)
            hook(cx, &frame, JS_FALSE, &ok, hookData);
    }

    /* If frame has a call object, sync values and clear back-pointer. */
    if (frame.callobj)
        ok &= js_PutCallObject(cx, &frame);

    /* If frame has an arguments object, sync values and clear back-pointer. */
    if (frame.argsobj)
        ok &= js_PutArgsObject(cx, &frame);

    /* Restore cx->fp now that we're done releasing frame objects. */
    cx->fp = fp;

out2:
    /* Pop everything we may have allocated off the stack. */
    JS_ARENA_RELEASE(&cx->stackPool, mark);

    /* Store the return value and restore sp just above it. */
    *vp = frame.rval;
    fp->sp = vp + 1;

    /*
     * Store the location of the JSOP_CALL or JSOP_EVAL that generated the
     * return value, but only if this is an external (compiled from script
     * source) call that has stack budget for the generating pc.
     */
    if (fp->script && !(flags & JSINVOKE_INTERNAL))
        vp[-(intN)fp->script->depth] = (jsval)fp->pc;
    return ok;

bad:
    js_ReportIsNotFunction(cx, vp, flags & JSINVOKE_FUNFLAGS);
    ok = JS_FALSE;
    goto out2;
}

JSBool
js_InternalInvoke(JSContext *cx, JSObject *obj, jsval fval, uintN flags,
                  uintN argc, jsval *argv, jsval *rval)
{
    JSStackFrame *fp, *oldfp, frame;
    jsval *oldsp, *sp;
    void *mark;
    uintN i;
    JSBool ok;

    fp = oldfp = cx->fp;
    if (!fp) {
        memset(&frame, 0, sizeof frame);
        cx->fp = fp = &frame;
    }
    oldsp = fp->sp;
    sp = js_AllocStack(cx, 2 + argc, &mark);
    if (!sp) {
        ok = JS_FALSE;
        goto out;
    }

    PUSH(fval);
    PUSH(OBJECT_TO_JSVAL(obj));
    for (i = 0; i < argc; i++)
        PUSH(argv[i]);
    SAVE_SP(fp);
    ok = js_Invoke(cx, argc, flags | JSINVOKE_INTERNAL);
    if (ok) {
        RESTORE_SP(fp);

        /*
         * Store *rval in the a scoped local root if a scope is open, else in
         * the lastInternalResult pigeon-hole GC root, solely so users of
         * js_InternalInvoke and its direct and indirect (js_ValueToString for
         * example) callers do not need to manage roots for local, temporary
         * references to such results.
         */
        *rval = POP_OPND();
        if (JSVAL_IS_GCTHING(*rval)) {
            if (cx->localRootStack) {
                if (js_PushLocalRoot(cx, cx->localRootStack, *rval) < 0)
                    ok = JS_FALSE;
            } else {
                cx->weakRoots.lastInternalResult = *rval;
            }
        }
    }

    js_FreeStack(cx, mark);
out: