jsexn.c

java script test programing source code

    if (!name)
        return JS_FALSE;
    *rval = STRING_TO_JSVAL(name);

    if (!JS_GetProperty(cx, obj, js_message_str, &vp[0]) ||
        !(message = js_ValueToSource(cx, vp[0]))) {
        return JS_FALSE;
    }
    vp[0] = STRING_TO_JSVAL(message);

    if (!JS_GetProperty(cx, obj, js_fileName_str, &vp[1]) ||
        !(filename = js_ValueToSource(cx, vp[1]))) {
        return JS_FALSE;
    }
    vp[1] = STRING_TO_JSVAL(filename);

    if (!JS_GetProperty(cx, obj, js_lineNumber_str, &vp[2]) ||
        !js_ValueToECMAUint32 (cx, vp[2], &lineno)) {
        return JS_FALSE;
    }

    if (lineno != 0) {
        lineno_as_str = js_ValueToString(cx, vp[2]);
        if (!lineno_as_str)
            return JS_FALSE;
        lineno_length = JSSTRING_LENGTH(lineno_as_str);
    } else {
        lineno_as_str = NULL;
        lineno_length = 0;
    }

    /* Magic 8, for the characters in ``(new ())''. */
    name_length = JSSTRING_LENGTH(name);
    message_length = JSSTRING_LENGTH(message);
    length = 8 + name_length + message_length;

    filename_length = JSSTRING_LENGTH(filename);
    if (filename_length != 0) {
        /* append filename as ``, {filename}'' */
        length += 2 + filename_length;
        if (lineno_as_str) {
            /* append lineno as ``, {lineno_as_str}'' */
            length += 2 + lineno_length;
        }
    } else {
        if (lineno_as_str) {
            /*
             * no filename, but have line number,
             * need to append ``, "", {lineno_as_str}''
             */
            length += 6 + lineno_length;
        }
    }

    cp = chars = (jschar*) JS_malloc(cx, (length + 1) * sizeof(jschar));
    if (!chars)
        return JS_FALSE;

    *cp++ = '('; *cp++ = 'n'; *cp++ = 'e'; *cp++ = 'w'; *cp++ = ' ';
    js_strncpy(cp, JSSTRING_CHARS(name), name_length);
    cp += name_length;
    *cp++ = '(';
    if (message_length != 0) {
        js_strncpy(cp, JSSTRING_CHARS(message), message_length);
        cp += message_length;
    }

    if (filename_length != 0) {
        /* append filename as ``, {filename}'' */
        *cp++ = ','; *cp++ = ' ';
        js_strncpy(cp, JSSTRING_CHARS(filename), filename_length);
        cp += filename_length;
    } else {
        if (lineno_as_str) {
            /*
             * no filename, but have line number,
             * need to append ``, "", {lineno_as_str}''
             */
            *cp++ = ','; *cp++ = ' '; *cp++ = '"'; *cp++ = '"';
        }
    }
    if (lineno_as_str) {
        /* append lineno as ``, {lineno_as_str}'' */
        *cp++ = ','; *cp++ = ' ';
        js_strncpy(cp, JSSTRING_CHARS(lineno_as_str), lineno_length);
        cp += lineno_length;
    }

    *cp++ = ')'; *cp++ = ')'; *cp = 0;

    result = js_NewString(cx, chars, length, 0);
    if (!result) {
        JS_free(cx, chars);
        return JS_FALSE;
    }
    *rval = STRING_TO_JSVAL(result);
    return JS_TRUE;
}
#endif

static JSFunctionSpec exception_methods[] = {
#if JS_HAS_TOSOURCE
    {js_toSource_str,   exn_toSource,           0,0,3},
#endif
    {js_toString_str,   exn_toString,           0,0,0},
    {0,0,0,0,0}
};

JSObject *
js_InitExceptionClasses(JSContext *cx, JSObject *obj)
{
    JSObject *obj_proto, *protos[JSEXN_LIMIT];
    int i;

    /*
     * If lazy class initialization occurs for any Error subclass, then all
     * classes are initialized, starting with Error.  To avoid reentry and
     * redundant initialization, we must not pass a null proto parameter to
     * js_NewObject below, when called for the Error superclass.  We need to
     * ensure that Object.prototype is the proto of Error.prototype.
     *
     * See the equivalent code to ensure that parent_proto is non-null when
     * JS_InitClass calls js_NewObject, in jsapi.c.
     */
    if (!js_GetClassPrototype(cx, obj, INT_TO_JSID(JSProto_Object),
                              &obj_proto)) {
        return NULL;
    }

    if (!js_EnterLocalRootScope(cx))
        return NULL;

    /* Initialize the prototypes first. */
    for (i = 0; exceptions[i].name != 0; i++) {
        JSAtom *atom;
        JSFunction *fun;
        JSObject *funobj;
        JSString *nameString;
        int protoIndex = exceptions[i].protoIndex;

        /* Make the prototype for the current constructor name. */
        protos[i] = js_NewObject(cx, &js_ErrorClass,
                                 (protoIndex != JSEXN_NONE)
                                 ? protos[protoIndex]
                                 : obj_proto,
                                 obj);
        if (!protos[i])
            break;

        /* So exn_finalize knows whether to destroy private data. */
        OBJ_SET_SLOT(cx, protos[i], JSSLOT_PRIVATE, JSVAL_VOID);

        /* Make a constructor function for the current name. */
        atom = cx->runtime->atomState.classAtoms[exceptions[i].key];
        fun = js_DefineFunction(cx, obj, atom, exceptions[i].native, 3, 0);
        if (!fun)
            break;

        /* Make this constructor make objects of class Exception. */
        fun->clasp = &js_ErrorClass;

        /* Extract the constructor object. */
        funobj = fun->object;

        /* Make the prototype and constructor links. */
        if (!js_SetClassPrototype(cx, funobj, protos[i],
                                  JSPROP_READONLY | JSPROP_PERMANENT)) {
            break;
        }

        /* proto bootstrap bit from JS_InitClass omitted. */
        nameString = JS_NewStringCopyZ(cx, exceptions[i].name);
        if (!nameString)
            break;

        /* Add the name property to the prototype. */
        if (!JS_DefineProperty(cx, protos[i], js_name_str,
                               STRING_TO_JSVAL(nameString),
                               NULL, NULL,
                               JSPROP_ENUMERATE)) {
            break;
        }

        /* Finally, stash the constructor for later uses. */
        if (!js_SetClassObject(cx, obj, exceptions[i].key, funobj))
            break;
    }

    js_LeaveLocalRootScope(cx);
    if (exceptions[i].name)
        return NULL;

    /*
     * Add an empty message property.  (To Exception.prototype only,
     * because this property will be the same for all the exception
     * protos.)
     */
    if (!JS_DefineProperty(cx, protos[0], js_message_str,
                           STRING_TO_JSVAL(cx->runtime->emptyString),
                           NULL, NULL, JSPROP_ENUMERATE)) {
        return NULL;
    }
    if (!JS_DefineProperty(cx, protos[0], js_fileName_str,
                           STRING_TO_JSVAL(cx->runtime->emptyString),
                           NULL, NULL, JSPROP_ENUMERATE)) {
        return NULL;
    }
    if (!JS_DefineProperty(cx, protos[0], js_lineNumber_str,
                           INT_TO_JSVAL(0),
                           NULL, NULL, JSPROP_ENUMERATE)) {
        return NULL;
    }

    /*
     * Add methods only to Exception.prototype, because ostensibly all
     * exception types delegate to that.
     */
    if (!JS_DefineFunctions(cx, protos[0], exception_methods))
        return NULL;

    return protos[0];
}

const JSErrorFormatString*
js_GetLocalizedErrorMessage(JSContext* cx, void *userRef, const char *locale, const uintN errorNumber)
{
    const JSErrorFormatString *errorString = NULL;

    if (cx->localeCallbacks && cx->localeCallbacks->localeGetErrorMessage) {
        errorString = cx->localeCallbacks
                        ->localeGetErrorMessage(userRef, locale, errorNumber);
    }
    if (!errorString)
        errorString = js_GetErrorMessage(userRef, locale, errorNumber);
    return errorString;
}

#if defined ( DEBUG_mccabe ) && defined ( PRINTNAMES )
/* For use below... get character strings for error name and exception name */
static struct exnname { char *name; char *exception; } errortoexnname[] = {
#define MSG_DEF(name, number, count, exception, format) \
    {#name, #exception},
#include "js.msg"
#undef MSG_DEF
};
#endif /* DEBUG */

JSBool
js_ErrorToException(JSContext *cx, const char *message, JSErrorReport *reportp)
{
    JSErrNum errorNumber;
    const JSErrorFormatString *errorString;
    JSExnType exn;
    jsval tv[4];
    JSTempValueRooter tvr;
    JSBool ok;
    JSObject *errProto, *errObject;
    JSString *messageStr, *filenameStr;

    /*
     * Tell our caller to report immediately if cx has no active frames, or if
     * this report is just a warning.
     */
    JS_ASSERT(reportp);
    if (!cx->fp || JSREPORT_IS_WARNING(reportp->flags))
        return JS_FALSE;

    /* Find the exception index associated with this error. */
    errorNumber = (JSErrNum) reportp->errorNumber;
    errorString = js_GetLocalizedErrorMessage(cx, NULL, NULL, errorNumber);
    exn = errorString ? errorString->exnType : JSEXN_NONE;
    JS_ASSERT(exn < JSEXN_LIMIT);

#if defined( DEBUG_mccabe ) && defined ( PRINTNAMES )
    /* Print the error name and the associated exception name to stderr */
    fprintf(stderr, "%s\t%s\n",
            errortoexnname[errorNumber].name,
            errortoexnname[errorNumber].exception);
#endif

    /*
     * Return false (no exception raised) if no exception is associated
     * with the given error number.
     */
    if (exn == JSEXN_NONE)
        return JS_FALSE;

    /*
     * Prevent runaway recursion, just as the Exception native constructor
     * must do, via cx->creatingException.  If an out-of-memory error occurs,
     * no exception object will be created, but we don't assume that OOM is
     * the only kind of error that subroutines of this function called below
     * might raise.
     */
    if (cx->creatingException)
        return JS_FALSE;

    /* After this point the control must flow through the label out. */
    cx->creatingException = JS_TRUE;

    /* Protect the newly-created strings below from nesting GCs. */
    memset(tv, 0, sizeof tv);
    JS_PUSH_TEMP_ROOT(cx, sizeof tv / sizeof tv[0], tv, &tvr);

    /*
     * Try to get an appropriate prototype by looking up the corresponding
     * exception constructor name in the scope chain of the current context's
     * top stack frame, or in the global object if no frame is active.
     */
    ok = js_GetClassPrototype(cx, NULL, INT_TO_JSID(exceptions[exn].key),
                              &errProto);
    if (!ok)
        goto out;
    tv[0] = OBJECT_TO_JSVAL(errProto);

    errObject = js_NewObject(cx, &js_ErrorClass, errProto, NULL);
    if (!errObject) {
        ok = JS_FALSE;
        goto out;
    }
    tv[1] = OBJECT_TO_JSVAL(errObject);

    messageStr = JS_NewStringCopyZ(cx, message);
    if (!messageStr) {
        ok = JS_FALSE;
        goto out;
    }
    tv[2] = STRING_TO_JSVAL(messageStr);

    filenameStr = JS_NewStringCopyZ(cx, reportp->filename);
    if (!filenameStr) {
        ok = JS_FALSE;
        goto out;
    }
    tv[3] = STRING_TO_JSVAL(filenameStr);

    ok = InitExnPrivate(cx, errObject, messageStr, filenameStr,
                        reportp->lineno, reportp);
    if (!ok)
        goto out;

    JS_SetPendingException(cx, OBJECT_TO_JSVAL(errObject));

    /* Flag the error report passed in to indicate an exception was raised. */
    reportp->flags |= JSREPORT_EXCEPTION;

out:
    JS_POP_TEMP_ROOT(cx, &tvr);
    cx->creatingException = JS_FALSE;
    return ok;
}

JSBool
js_ReportUncaughtException(JSContext *cx)
{
    jsval exn;
    JSObject *exnObject;
    jsval vp[5];
    JSTempValueRooter tvr;
    JSErrorReport *reportp, report;
    JSString *str;
    const char *bytes;
    JSBool ok;

    if (!JS_IsExceptionPending(cx))
        return JS_TRUE;

    if (!JS_GetPendingException(cx, &exn))
        return JS_FALSE;

    /*
     * Because js_ValueToString below could error and an exception object
     * could become unrooted, we must root exnObject.  Later, if exnObject is
     * non-null, we need to root other intermediates, so allocate an operand
     * stack segment to protect all of these values.
     */
    if (JSVAL_IS_PRIMITIVE(exn)) {
        exnObject = NULL;
    } else {
        exnObject = JSVAL_TO_OBJECT(exn);
        vp[0] = exn;
        memset(vp + 1, 0, sizeof vp - sizeof vp[0]);
        JS_PUSH_TEMP_ROOT(cx, JS_ARRAY_LENGTH(vp), vp, &tvr);
    }

    JS_ClearPendingException(cx);
    reportp = js_ErrorFromException(cx, exn);

    /* XXX L10N angels cry once again (see also jsemit.c, /L10N gaffes/) */
    str = js_ValueToString(cx, exn);
    if (!str) {
        bytes = "unknown (can't convert to string)";
    } else {
        if (exnObject)
            vp[1] = STRING_TO_JSVAL(str);
        bytes = js_GetStringBytes(cx->runtime, str);
    }
    ok = JS_TRUE;

    if (!reportp &&
        exnObject &&
        OBJ_GET_CLASS(cx, exnObject) == &js_ErrorClass) {
        const char *filename;
        uint32 lineno;

        ok = JS_GetProperty(cx, exnObject, js_message_str, &vp[2]);
        if (!ok)
            goto out;
        if (JSVAL_IS_STRING(vp[2]))
            bytes = JS_GetStringBytes(JSVAL_TO_STRING(vp[2]));

        ok = JS_GetProperty(cx, exnObject, js_fileName_str, &vp[3]);
        if (!ok)
            goto out;
        str = js_ValueToString(cx, vp[3]);
        if (!str) {
            ok = JS_FALSE;
            goto out;
        }
        filename = StringToFilename(cx, str);

        ok = JS_GetProperty(cx, exnObject, js_lineNumber_str, &vp[4]);
        if (!ok)
            goto out;
        ok = js_ValueToECMAUint32 (cx, vp[4], &lineno);
        if (!ok)
            goto out;

        reportp = &report;
        memset(&report, 0, sizeof report);
        report.filename = filename;
        report.lineno = (uintN) lineno;
    }

    if (!reportp) {
        JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
                             JSMSG_UNCAUGHT_EXCEPTION, bytes);
    } else {
        /* Flag the error as an exception. */
        reportp->flags |= JSREPORT_EXCEPTION;
        js_ReportErrorAgain(cx, bytes, reportp);
    }

out:
    if (exnObject)
        JS_POP_TEMP_ROOT(cx, &tvr);
    return ok;
}