poll.h revision 46f5824f3e233b92bad1626932d5ce9522886f54
/** @file
* IPRT - Polling I/O Handles.
*/
/*
* Copyright (C) 2010 Sun Microsystems, Inc.
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* 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.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 USA or visit http://www.sun.com if you need
* additional information or have any questions.
*/
#ifndef ___iprt_poll_h
#define ___iprt_poll_h
#include <iprt/cdefs.h>
#include <iprt/types.h>
RT_C_DECLS_BEGIN
/** @defgroup grp_rt_poll RTPoll - Polling I/O Handles
* @ingroup grp_rt
* @{
*/
/** @name Poll events
* @{ */
/** Readable without blocking. */
#define RTPOLL_EVT_READ RT_BIT_32(0)
/** Writable without blocking. */
#define RTPOLL_EVT_WRITE RT_BIT_32(1)
/** Error condition, hangup, exception or similar. */
#define RTPOLL_EVT_ERROR RT_BIT_32(2)
/** Mask of the valid bits. */
#define RTPOLL_EVT_VALID_MASK UINT32_C(0x00000007)
/** @} */
/**
* Polls on the specified poll set until an event occures on one of the handles
* or the timeout expires.
*
* @returns IPRT status code.
* @retval VINF_SUCCESS if an event occured on a handle. Note that these
* @retval VERR_INVALID_HANDLE if @a hPollSet is invalid.
* @retval VERR_WRONG_ORDER if another thread is already accessing the set. The
* user is responsible for ensuring single threaded access.
* @retval VERR_TIMEOUT if @a cMillies ellapsed without any events.
* @retval VERR_DEADLOCK if @a cMillies is set to RT_INDEFINITE_WAIT and there
* are no valid handles in the set.
*
* @param hPollSet The set to poll on.
* @param cMillies Number of milliseconds to wait. Use
* RT_INDEFINITE_WAIT to wait for ever.
* @param pfEvents Where to return details about the events that
* occured. Optional.
* @param pid Where to return the ID associated with the
* handle when calling RTPollSetAdd. Optional.
*
* @sa RTPollNoResume
*
* @remarks The caller is responsible for ensuring
*/
RTDECL(int) RTPoll(RTPOLLSET hPollSet, RTMSINTERVAL cMillies, uint32_t *pfEvents, uint32_t *pid);
/**
* Same as RTPoll except that it will return when interrupted.
*
* @returns IPRT status code.
* @retval VINF_SUCCESS if an event occured on a handle. Note that these
* @retval VERR_INVALID_HANDLE if @a hPollSet is invalid.
* @retval VERR_WRONG_ORDER if another thread is already accessing the set. The
* user is responsible for ensuring single threaded access.
* @retval VERR_TIMEOUT if @a cMillies ellapsed without any events.
* @retval VERR_DEADLOCK if @a cMillies is set to RT_INDEFINITE_WAIT and there
* are no valid handles in the set.
* @retval VERR_INTERRUPTED if a signal or other asynchronous event interrupted
* the polling.
*
* @param hPollSet The set to poll on.
* @param cMillies Number of milliseconds to wait. Use
* RT_INDEFINITE_WAIT to wait for ever.
* @param pfEvents Where to return details about the events that
* occured. Optional.
* @param pid Where to return the ID associated with the
* handle when calling RTPollSetAdd. Optional.
*/
RTDECL(int) RTPollNoResume(RTPOLLSET hPollSet, RTMSINTERVAL cMillies, uint32_t *pfEvents, uint32_t *pid);
/**
* Creates a poll set with no members.
*
* @returns IPRT status code.
* @param phPollSet Where to return the poll set handle.
*/
RTDECL(int) RTPollSetCreate(PRTPOLLSET phPollSet);
/**
* Destroys a poll set.
*
* @returns IPRT status code.
* @param hPollSet The poll set to destroy. NIL_POLLSET is quietly
* ignored (VINF_SUCCESS).
*/
RTDECL(int) RTPollSetDestroy(RTPOLLSET hPollSet);
/**
* Adds a generic handle to the poll set.
*
* @returns IPRT status code
* @retval VERR_WRONG_ORDER if another thread is already accessing the set. The
* user is responsible for ensuring single threaded access.
* @retval VERR_POLL_HANDLE_NOT_POLLABLE if the specified handle is not
* pollable.
* @retval VERR_POLL_HANDLE_ID_EXISTS if the handle ID is already in use in the
* set.
*
* @param hPollSet The poll set to modify.
* @param pHandle The handle to add. NIL handles are quitely
* ignored.
* @param fEvents Which events to poll for.
* @param id The handle ID.
*/
RTDECL(int) RTPollSetAdd(RTPOLLSET hPollSet, PCRTHANDLE pHandle, uint32_t fEvents, uint32_t id);
/**
* Removes a generic handle from the poll set.
*
* @returns IPRT status code
* @retval VERR_INVALID_HANDLE if @a hPollSet not valid.
* @retval VERR_WRONG_ORDER if another thread is already accessing the set. The
* user is responsible for ensuring single threaded access.
* @retval VERR_POLL_HANDLE_ID_NOT_FOUND if @a id doesn't resolve to a valid
* handle.
*
* @param hPollSet The poll set to modify.
* @param id The handle ID of the handle that should be
* removed.
*/
RTDECL(int) RTPollSetRemove(RTPOLLSET hPollSet, uint32_t id);
/**
* Query a handle in the poll set by it's ID.
*
* @returns IPRT status code
* @retval VINF_SUCCESS if the handle was found. @a *pHandle is set.
* @retval VERR_INVALID_HANDLE if @a hPollSet is invalid.
* @retval VERR_WRONG_ORDER if another thread is already accessing the set. The
* user is responsible for ensuring single threaded access.
* @retval VERR_POLL_HANDLE_ID_NOT_FOUND if there is no handle with that ID.
*
* @param hPollSet The poll set to query.
* @param id The ID of the handle.
* @param pHandle Where to return the handle details. Optional.
*/
RTDECL(int) RTPollSetQueryHandle(RTPOLLSET hPollSet, uint32_t id, PRTHANDLE pHandle);
/**
* Gets the number of handles in the set.
*
* @retval The handle count.
* @retval UINT32_MAX if @a hPollSet is invalid or there is concurrent access.
*
* @param hPollSet The poll set.
*/
RTDECL(uint32_t) RTPollSetCount(RTPOLLSET hPollSet);
/**
* Adds a pipe handle to the set.
*
* @returns See RTPollSetAdd.
*
* @param hPollSet The poll set.
* @param hPipe The pipe handle.
* @param fEvents Which events to poll for.
* @param id The handle ID.
*
* @todo Maybe we could figure out what to poll for depending on the kind of
* pipe we're dealing with.
*/
DECLINLINE(int) RTPollSetAddPipe(RTPOLLSET hPollSet, RTPIPE hPipe, uint32_t fEvents, uint32_t id)
{
RTHANDLE Handle;
Handle.enmType = RTHANDLETYPE_PIPE;
Handle.u.hPipe = hPipe;
return RTPollSetAdd(hPollSet, &Handle, fEvents, id);
}
/**
* Adds a socket handle to the set.
*
* @returns See RTPollSetAdd.
*
* @param hPollSet The poll set.
* @param hSocket The socket handle.
* @param fEvents Which events to poll for.
* @param id The handle ID.
*/
DECLINLINE(int) RTPollSetAddSocket(RTPOLLSET hPollSet, RTSOCKET hSocket, uint32_t fEvents, uint32_t id)
{
RTHANDLE Handle;
Handle.enmType = RTHANDLETYPE_SOCKET;
Handle.u.hSocket = hSocket;
return RTPollSetAdd(hPollSet, &Handle, fEvents, id);
}
/** @} */
RT_C_DECLS_END
#endif