req.h revision 36411046d85fccaa66061120a064225fd1b5ae01
/** @file
* IPRT - Request Queue & Pool.
*/
/*
* Copyright (C) 2006-2011 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
* VirtualBox OSE distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*/
#ifndef ___iprt_req_h
#define ___iprt_req_h
/** @defgroup grp_rt_req RTReq - Request Queue & Pool.
* @ingroup grp_rt
* @{
*/
/** Request queue handle. */
typedef struct RTREQQUEUEINT *RTREQQUEUE;
/** Pointer to a request queue handle. */
typedef RTREQQUEUE *PRTREQQUEUE;
/** NIL request queue handle. */
#define NIL_RTREQQUEUE ((RTREQQUEUE)0)
/** Request thread pool handle. */
typedef struct RTREQPOOLINT *RTREQPOOL;
/** Poiner to a request thread pool handle. */
typedef RTREQPOOL *PRTREQPOOL;
/** NIL request pool handle. */
#define NIL_RTREQPOOL ((RTREQPOOL)0)
/**
* Request type.
*/
typedef enum RTREQTYPE
{
/** Invalid request. */
RTREQTYPE_INVALID = 0,
/** RT: Internal. */
/** Maximum request type (exclusive). Used for validation. */
} RTREQTYPE;
/**
* Request state.
*/
typedef enum RTREQSTATE
{
/** The state is invalid. */
RTREQSTATE_INVALID = 0,
/** The request have been allocated and is in the process of being filed. */
/** The request is queued by the requester. */
/** The request is begin processed. */
/** The request is completed, the requester is begin notified. */
/** The request packet is in the free chain. (The requester */
} RTREQSTATE;
/**
* Request flags.
*/
typedef enum RTREQFLAGS
{
/** The request returns a iprt status code. */
/** The request is a void request and have no status code. */
RTREQFLAGS_VOID = 1,
/** Return type mask. */
/** Caller does not wait on the packet, Queue process thread will free it. */
} RTREQFLAGS;
/**
* RT Request packet.
*
* This is used to request an action in the queue handler thread.
*/
typedef struct RTREQ
{
/** Pointer to the next request in the chain. */
/** Pointer to the queue this packet belongs to. */
/** Request state. */
volatile RTREQSTATE enmState;
/** iprt status code for the completed request. */
volatile int iStatus;
/** Requester event sem.
* of the request.
*/
/** Set if the event semaphore is clear. */
volatile bool fEventSemClear;
/** Flags, RTREQ_FLAGS_*. */
unsigned fFlags;
/** Request type. */
/** Request specific data. */
union RTREQ_U
{
/** RTREQTYPE_INTERNAL. */
struct
{
/** Pointer to the function to be called. */
/** Number of arguments. */
unsigned cArgs;
/** Array of arguments. */
} Internal;
} u;
} RTREQ;
/** Pointer to an RT request packet. */
#ifdef IN_RING3
/**
* Create a request packet queue
*
* @returns iprt status code.
* @param phQueue Where to store the request queue handle.
*/
/**
* Destroy a request packet queue
*
* @returns iprt status code.
* @param hQueue The request queue.
*/
/**
* Process one or more request packets
*
* @returns iprt status code.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being added.
*
* @param hQueue The request queue.
* @param cMillies Number of milliseconds to wait for a pending request.
* Use RT_INDEFINITE_WAIT to only wait till one is added.
*/
/**
* Allocate and queue a call request.
*
* If it's desired to poll on the completion of the request set cMillies
* to 0 and use RTReqWait() to check for completion. In the other case
* use RT_INDEFINITE_WAIT.
* The returned request packet must be freed using RTReqFree().
*
* @returns iprt statuscode.
* Will not return VERR_INTERRUPTED.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being completed.
*
* @param hQueue The request queue.
* @param ppReq Where to store the pointer to the request.
* This will be NULL or a valid request pointer not matter what happens.
* @param cMillies Number of milliseconds to wait for the request to
* be completed. Use RT_INDEFINITE_WAIT to only
* wait till it's completed.
* @param pfnFunction Pointer to the function to call.
* @param cArgs Number of arguments following in the ellipsis.
* @param ... Function arguments.
*
* @remarks See remarks on RTReqQueueCallV.
*/
RTDECL(int) RTReqQueueCall(RTREQQUEUE hQueue, PRTREQ *ppReq, RTMSINTERVAL cMillies, PFNRT pfnFunction, unsigned cArgs, ...);
/**
* Allocate and queue a call request to a void function.
*
* If it's desired to poll on the completion of the request set cMillies
* to 0 and use RTReqWait() to check for completion. In the other case
* use RT_INDEFINITE_WAIT.
* The returned request packet must be freed using RTReqFree().
*
* @returns iprt status code.
* Will not return VERR_INTERRUPTED.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being completed.
*
* @param hQueue The request queue.
* @param ppReq Where to store the pointer to the request.
* This will be NULL or a valid request pointer not matter what happens.
* @param cMillies Number of milliseconds to wait for the request to
* be completed. Use RT_INDEFINITE_WAIT to only
* wait till it's completed.
* @param pfnFunction Pointer to the function to call.
* @param cArgs Number of arguments following in the ellipsis.
* @param ... Function arguments.
*
* @remarks See remarks on RTReqQueueCallV.
*/
RTDECL(int) RTReqQueueCallVoid(RTREQQUEUE hQueue, PRTREQ *ppReq, RTMSINTERVAL cMillies, PFNRT pfnFunction, unsigned cArgs, ...);
/**
* Allocate and queue a call request to a void function.
*
* If it's desired to poll on the completion of the request set cMillies
* to 0 and use RTReqWait() to check for completion. In the other case
* use RT_INDEFINITE_WAIT.
* The returned request packet must be freed using RTReqFree().
*
* @returns iprt status code.
* Will not return VERR_INTERRUPTED.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being completed.
*
* @param hQueue The request queue.
* @param ppReq Where to store the pointer to the request.
* This will be NULL or a valid request pointer not matter what happens, unless fFlags
* contains RTREQFLAGS_NO_WAIT when it will be optional and always NULL.
* @param cMillies Number of milliseconds to wait for the request to
* be completed. Use RT_INDEFINITE_WAIT to only
* wait till it's completed.
* @param fFlags A combination of the RTREQFLAGS values.
* @param pfnFunction Pointer to the function to call.
* @param cArgs Number of arguments following in the ellipsis.
* @param ... Function arguments.
*
* @remarks See remarks on RTReqQueueCallV.
*/
RTDECL(int) RTReqQueueCallEx(RTREQQUEUE hQueue, PRTREQ *ppReq, RTMSINTERVAL cMillies, unsigned fFlags, PFNRT pfnFunction, unsigned cArgs, ...);
/**
* Allocate and queue a call request.
*
* If it's desired to poll on the completion of the request set cMillies
* to 0 and use RTReqWait() to check for completion. In the other case
* use RT_INDEFINITE_WAIT.
* The returned request packet must be freed using RTReqFree().
*
* @returns iprt status code.
* Will not return VERR_INTERRUPTED.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being completed.
*
* @param hQueue The request queue.
* @param ppReq Where to store the pointer to the request.
* This will be NULL or a valid request pointer not matter what happens, unless fFlags
* contains RTREQFLAGS_NO_WAIT when it will be optional and always NULL.
* @param cMillies Number of milliseconds to wait for the request to
* be completed. Use RT_INDEFINITE_WAIT to only
* wait till it's completed.
* @param fFlags A combination of the RTREQFLAGS values.
* @param pfnFunction Pointer to the function to call.
* @param cArgs Number of arguments following in the ellipsis.
* @param Args Variable argument vector.
*
* @remarks Caveats:
* - Do not pass anything which is larger than an uintptr_t.
* - 64-bit integers are larger than uintptr_t on 32-bit hosts.
* Pass integers > 32-bit by reference (pointers).
* - Don't use NULL since it should be the integer 0 in C++ and may
* therefore end up with garbage in the bits 63:32 on 64-bit
* hosts because 'int' is 32-bit.
* Use (void *)NULL or (uintptr_t)0 instead of NULL.
*/
RTDECL(int) RTReqQueueCallV(RTREQQUEUE hQueue, PRTREQ *ppReq, RTMSINTERVAL cMillies, unsigned fFlags, PFNRT pfnFunction, unsigned cArgs, va_list Args);
/**
* Checks if the queue is busy or not.
*
* The caller is responsible for dealing with any concurrent submitts.
*
* @returns true if busy, false if idle.
* @param hQueue The queue.
*/
/**
* Allocates a request packet.
*
* The caller allocates a request packet, fills in the request data
* union and queues the request.
*
* @returns iprt status code.
*
* @param hQueue The request queue.
* @param ppReq Where to store the pointer to the allocated packet.
* @param enmType Package type.
*/
/**
* Free a request packet.
*
* @returns iprt status code.
*
* @param pReq Package to free.
* @remark The request packet must be in allocated or completed state!
*/
/**
* Queue a request.
*
* The quest must be allocated using RTReqQueueAlloc() or RTReqPoolAlloc() and
* contain all the required data.
*
* If it's desired to poll on the completion of the request set cMillies
* to 0 and use RTReqWait() to check for completion. In the other case
* use RT_INDEFINITE_WAIT.
*
* @returns iprt status code.
* Will not return VERR_INTERRUPTED.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being completed.
*
* @param pReq The request to queue.
* @param cMillies Number of milliseconds to wait for the request to
* be completed. Use RT_INDEFINITE_WAIT to only
* wait till it's completed.
*/
/**
* Wait for a request to be completed.
*
* @returns iprt status code.
* Will not return VERR_INTERRUPTED.
* @returns VERR_TIMEOUT if cMillies was reached without the packet being completed.
*
* @param pReq The request to wait for.
* @param cMillies Number of milliseconds to wait.
* Use RT_INDEFINITE_WAIT to only wait till it's completed.
*/
#endif /* IN_RING3 */
/** @} */
#endif