/*
* Copyright (c) 2020 Red Hat, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* $Id: //eng/uds-releases/jasper/src/uds/indexRouter.h#3 $
*/
#ifndef INDEX_ROUTER_H
#define INDEX_ROUTER_H
#include "compiler.h"
#include "index.h"
#include "indexSession.h"
#include "request.h"
/**
* Callback after a query, update or remove request completes and fills in
* select fields in the request: status for all requests, oldMetadata and
* hashExists for query and update requests.
*
* @param request request object.
**/
typedef void (*IndexRouterCallback)(Request *request);
struct indexRouter {
IndexRouterCallback callback;
unsigned int zoneCount;
bool needToSave;
Index *index;
RequestQueue *triageQueue;
RequestQueue *zoneQueues[];
};
/**
* Construct and initialize an IndexRouter instance.
*
* @param layout the IndexLayout that describes the stored index
* @param config the configuration to use
* @param userParams the index session parameters. If NULL, the default
* session parameters will be used.
* @param loadType selects whether to create, load, or rebuild the index
* @param loadContext the index load context to use
* @param callback the function to invoke when a request completes or fails
* @param routerPtr a pointer in which to store the new router
*
* @return UDS_SUCCESS or an error code
**/
int makeIndexRouter(IndexLayout *layout,
const Configuration *config,
const struct uds_parameters *userParams,
LoadType loadType,
IndexLoadContext *loadContext,
IndexRouterCallback callback,
IndexRouter **routerPtr)
__attribute__((warn_unused_result));
/**
* Executes the index operation for a UDS request and calls the callback upon
* completion.
*
* @param router The index router.
* @param request A pointer to the Request to process.
**/
void executeIndexRouterRequest(IndexRouter *router, Request *request);
/**
* Save the index router state to persistent storage.
*
* It is the responsibility of the caller to ensure that there are no other
* uses of the index during a call to this method. It is necessary that there
* be no index requests from any block context nor any other attempt to save
* the index until after a call to saveIndexRouter returns.
*
* @param router the index router to save
*
* @return UDS_SUCCESS if successful.
**/
int saveIndexRouter(IndexRouter *router) __attribute__((warn_unused_result));
/**
* Destroy the index router and free its memory.
*
* @param router the index router to destroy (may be NULL)
*
* @return UDS_SUCCESS if successful.
**/
void freeIndexRouter(IndexRouter *router);
/**
* Select and return the request queue responsible for executing the next
* index stage of a request, updating the request with any associated state
* (such as the zone number for UDS requests on a local index).
*
* @param router The index router.
* @param request The Request destined for the queue.
* @param nextStage The next request stage (STAGE_TRIAGE or STAGE_INDEX).
*
* @return the next index stage queue (the local triage queue, local zone
* queue, or remote RPC send queue)
**/
RequestQueue *selectIndexRouterQueue(IndexRouter *router,
Request *request,
RequestStage nextStage);
/**
* Wait for the index router to finish all operations that access a local
* storage device.
*
* @param router The index router.
**/
static INLINE void waitForIdleIndexRouter(IndexRouter *router)
{
waitForIdleChapterWriter(router->index->chapterWriter);
}
#endif /* INDEX_ROUTER_H */