/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at
http://mozilla.org/MPL/2.0/. */
#include "nsISupports.idl"
/**
* Utilities for running nested event loops, asking them to return, and
* keeping track of which ones are still running.
*/
[scriptable, uuid(6758d0d7-e96a-4c5c-bca8-3bcbe5a15943)]
interface nsIJSInspector : nsISupports
{
/**
* Process the current thread's event queue, calling event handlers until
* a call to exitNestedEventLoop, below, asks us to return.
*
* The name 'enterNestedEventLoop' may be misleading if read too literally.
* This method loops calling event handlers until one asks it to stop, and
* then returns. So by that point, the nested event loop has been not only
* entered, but also run and exited.
*
* When enterNestedEventLoop calls an event handler, that handler may itself
* call enterNestedEventLoop, and so on, so that there may be arbitrarily
* many such calls on the stack at the same time.
*
* We say an enterNestedEventLoop call is "running" if it has not yet been
* asked to return, or "stopped" if it has been asked to return once it has
* finished processing the current event.
*
* @param requestor A token of the caller's choice to identify this event
* loop.
*
* @return depth The number of running enterNestedEventLoop calls
* remaining, now that this one has returned.
*
* (Note that not all calls still on the stack are
* necessary running; exitNestedEventLoop can ask any
* number of enterNestedEventLoop calls to return.)
*/
unsigned long enterNestedEventLoop(in jsval requestor);
/**
* Stop the youngest running enterNestedEventLoop call, asking it to return
* once it has finished processing the current event.
*
* The name 'exitNestedEventLoop' may be misleading if read too literally.
* The affected event loop does not return immediately when this method is
* called. Rather, this method simply returns to its caller; the affected
* loop's current event handler is allowed to run to completion; and then
* that loop returns without processing any more events.
*
* This method ignores loops that have already been stopped, and operates on
* the youngest loop that is still running. Each call to this method stops
* another running loop.
*
* @return depth The number of running enterNestedEventLoop calls
* remaining, now that one has been stopped.
*
* @throws NS_ERROR_FAILURE if there are no running enterNestedEventLoop calls.
*/
unsigned long exitNestedEventLoop();
/**
* The number of running enterNestedEventLoop calls on the stack.
* This count does not include stopped enterNestedEventLoop calls.
*/
readonly attribute unsigned long eventLoopNestLevel;
/**
* The |requestor| value that was passed to the youngest running
* enterNestedEventLoop call.
*/
readonly attribute jsval lastNestRequestor;
};
