static char* FormatJSStackDump(JSContext* cx, char* buf,
                               JSBool showArgs, JSBool showLocals,
                               JSBool showThisProps)
{
    JSStackFrame* fp;
    JSStackFrame* iter = nsnull;
    int num = 0;

    while (nsnull != (fp = JS_FrameIterator(cx, &iter))) {
        buf = FormatJSFrame(cx, fp, buf, num, showArgs, showLocals, showThisProps);
        num++;
    }

    if (!num)
        buf = JS_sprintf_append(buf, "JavaScript stack is empty\n");

    return buf;
}
Exemple #2
0
static char* FormatJSFrame(JSContext* cx, JSStackFrame* fp,
                           char* buf, int num,
                           JSBool showArgs, JSBool showLocals, JSBool showThisProps)
{
    JSPropertyDescArray callProps = {0, nsnull};
    JSPropertyDescArray thisProps = {0, nsnull};
    JSBool gotThisVal = JS_FALSE;
    jsval thisVal;
    JSObject* callObj = nsnull;
    JSString* funname = nsnull;
    JSAutoByteString funbytes;
    const char* filename = nsnull;
    PRInt32 lineno = 0;
    JSFunction* fun = nsnull;
    uint32 namedArgCount = 0;
    jsval val;
    JSBool isString;

    // get the info for this stack frame

    JSScript* script = JS_GetFrameScript(cx, fp);
    jsbytecode* pc = JS_GetFramePC(cx, fp);

    JSAutoRequest ar(cx);
    JSAutoEnterCompartment ac;
    if(!ac.enter(cx, JS_GetFrameScopeChain(cx, fp)))
        return buf;

    if(script && pc)
    {
        filename = JS_GetScriptFilename(cx, script);
        lineno =  (PRInt32) JS_PCToLineNumber(cx, script, pc);
        fun = JS_GetFrameFunction(cx, fp);
        if(fun)
            funname = JS_GetFunctionId(fun);

        if(showArgs || showLocals)
        {
            callObj = JS_GetFrameCallObject(cx, fp);
            if(callObj)
                if(!JS_GetPropertyDescArray(cx, callObj, &callProps))
                    callProps.array = nsnull;  // just to be sure
        }

        gotThisVal = JS_GetFrameThis(cx, fp, &thisVal);
        if (!gotThisVal ||
            !showThisProps ||
            JSVAL_IS_PRIMITIVE(thisVal) ||
            !JS_GetPropertyDescArray(cx, JSVAL_TO_OBJECT(thisVal),
                                     &thisProps))
        {
            thisProps.array = nsnull;  // just to be sure
        }
    }

    // print the frame number and function name

    if(funname)
        buf = JS_sprintf_append(buf, "%d %s(", num, funbytes.encode(cx, funname));
    else if(fun)
        buf = JS_sprintf_append(buf, "%d anonymous(", num);
    else
        buf = JS_sprintf_append(buf, "%d <TOP LEVEL>", num);
    if(!buf) goto out;

    // print the function arguments

    if(showArgs && callObj)
    {
        for(uint32 i = 0; i < callProps.length; i++)
        {
            JSPropertyDesc* desc = &callProps.array[i];
            if(desc->flags & JSPD_ARGUMENT)
            {
                JSAutoByteString nameBytes;
                const char* name = JSVAL2String(cx, desc->id, &isString, &nameBytes);
                if(!isString)
                    name = nsnull;
                JSAutoByteString valueBytes;
                const char* value = JSVAL2String(cx, desc->value, &isString, &valueBytes);
                
                buf = JS_sprintf_append(buf, "%s%s%s%s%s%s",
                                        namedArgCount ? ", " : "",
                                        name ? name :"",
                                        name ? " = " : "",
                                        isString ? "\"" : "",
                                        value ? value : "?unknown?",
                                        isString ? "\"" : "");
                if(!buf) goto out;
                namedArgCount++;
            }
        }

        // print any unnamed trailing args (found in 'arguments' object)

        if(JS_GetProperty(cx, callObj, "arguments", &val) &&
           JSVAL_IS_OBJECT(val))
        {
            uint32 argCount;
            JSObject* argsObj = JSVAL_TO_OBJECT(val);
            if(JS_GetProperty(cx, argsObj, "length", &val) &&
               JS_ValueToECMAUint32(cx, val, &argCount) &&
               argCount > namedArgCount)
            {
                for(uint32 k = namedArgCount; k < argCount; k++)
                {
                    char number[8];
                    JS_snprintf(number, 8, "%d", (int) k);

                    if(JS_GetProperty(cx, argsObj, number, &val))
                    {
                        JSAutoByteString valueBytes;
                        const char *value = JSVAL2String(cx, val, &isString, &valueBytes);
                        buf = JS_sprintf_append(buf, "%s%s%s%s",
                                        k ? ", " : "",
                                        isString ? "\"" : "",
                                        value ? value : "?unknown?",
                                        isString ? "\"" : "");
                        if(!buf) goto out;
                    }
                }
            }
        }
    }

    // print filename and line number

    buf = JS_sprintf_append(buf, "%s [\"%s\":%d]\n",
                            fun ? ")" : "",
                            filename ? filename : "<unknown>",
                            lineno);
    if(!buf) goto out;

    // print local variables

    if(showLocals && callProps.array)
    {
        for(uint32 i = 0; i < callProps.length; i++)
        {
            JSPropertyDesc* desc = &callProps.array[i];
            if(desc->flags & JSPD_VARIABLE)
            {
                JSAutoByteString nameBytes;
                JSAutoByteString valueBytes;
                const char *name = JSVAL2String(cx, desc->id, nsnull, &nameBytes);
                const char *value = JSVAL2String(cx, desc->value, &isString, &valueBytes);

                if(name && value)
                {
                    buf = JS_sprintf_append(buf, TAB "%s = %s%s%s\n",
                                            name,
                                            isString ? "\"" : "",
                                            value,
                                            isString ? "\"" : "");
                    if(!buf) goto out;
                }
            }
        }
    }

    // print the value of 'this'

    if(showLocals)
    {
        if(gotThisVal)
        {
            JSString* thisValStr;
            JSAutoByteString thisValBytes;

            if(nsnull != (thisValStr = JS_ValueToString(cx, thisVal)) &&
               thisValBytes.encode(cx, thisValStr))
            {
                buf = JS_sprintf_append(buf, TAB "this = %s\n", thisValBytes.ptr());
                if(!buf) goto out;
            }
        }
        else
            buf = JS_sprintf_append(buf, TAB "<failed to get 'this' value>\n");
    }

    // print the properties of 'this', if it is an object

    if(showThisProps && thisProps.array)
    {

        for(uint32 i = 0; i < thisProps.length; i++)
        {
            JSPropertyDesc* desc = &thisProps.array[i];
            if(desc->flags & JSPD_ENUMERATE)
            {
                JSAutoByteString nameBytes;
                JSAutoByteString valueBytes;
                const char *name = JSVAL2String(cx, desc->id, nsnull, &nameBytes);
                const char *value = JSVAL2String(cx, desc->value, &isString, &valueBytes);
                if(name && value)
                {
                    buf = JS_sprintf_append(buf, TAB "this.%s = %s%s%s\n",
                                            name,
                                            isString ? "\"" : "",
                                            value,
                                            isString ? "\"" : "");
                    if(!buf) goto out;
                }
            }
        }
    }

out:
    if(callProps.array)
        JS_PutPropertyDescArray(cx, &callProps);
    if(thisProps.array)
        JS_PutPropertyDescArray(cx, &thisProps);
    return buf;
}