common/misc/handletablectx.cpp

	handletablectx.cpp revision cc66247640b520463f925a5533fc9e5de06aa982
cc66247640b520463f925a5533fc9e5de06aa982vboxsync/* $Id$ */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync/** @file
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * IPRT - Handle Tables.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync/*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * Copyright (C) 2008 Sun Microsystems, Inc.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync *
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * This file is part of VirtualBox Open Source Edition (OSE), as
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * available from http://www.virtualbox.org. This file is free software;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * you can redistribute it and/or modify it under the terms of the GNU
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * General Public License (GPL) as published by the Free Software
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * Foundation, in version 2 as it comes in the "COPYING" file of the
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync *
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * The contents of this file may alternatively be used under the terms
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * of the Common Development and Distribution License Version 1.0
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * VirtualBox OSE distribution, in which case the provisions of the
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * CDDL are applicable instead of those of the GPL.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync *
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * You may elect to license modified versions of this file under the
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * terms and conditions of either the GPL or the CDDL or both.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync *
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * Clara, CA 95054 USA or visit http://www.sun.com if you need
cc66247640b520463f925a5533fc9e5de06aa982vboxsync * additional information or have any questions.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync/*******************************************************************************
cc66247640b520463f925a5533fc9e5de06aa982vboxsync*   Header Files                                                               *
cc66247640b520463f925a5533fc9e5de06aa982vboxsync*******************************************************************************/
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/handletable.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/mem.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/spinlock.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/err.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/assert.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/param.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/string.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include <iprt/asm.h>
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include "internal/magics.h"
cc66247640b520463f925a5533fc9e5de06aa982vboxsync#include "handletable.h"
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsyncRTDECL(int)     RTHandleTableAllocWithCtx(RTHANDLETABLE hHandleTable, void *pvObj, void *pvCtx, uint32_t *ph)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync{
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* validate the input */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    PRTHANDLETABLEINT pThis = (PRTHANDLETABLEINT)hHandleTable;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(pThis->u32Magic == RTHANDLETABLE_MAGIC, VERR_INVALID_HANDLE);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(pThis->fFlags & RTHANDLETABLE_FLAGS_CONTEXT, VERR_INVALID_FUNCTION);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(!RTHT_IS_FREE(pvObj), VERR_INVALID_PARAMETER);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertPtrReturn(ph, VERR_INVALID_POINTER);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    *ph = pThis->uBase - 1;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync     * Allocation loop.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync     */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    RTSPINLOCKTMP Tmp;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    rtHandleTableLock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    int rc;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    do
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync         * Try grab a free entry from the head of the free list.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync         */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        uint32_t i = pThis->iFreeHead;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        if (i != NIL_RTHT_INDEX)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            PRTHTENTRYFREE pFree = (PRTHTENTRYFREE)rtHandleTableLookupWithCtxIdx(pThis, i);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            Assert(pFree);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (i == pThis->iFreeTail)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pThis->iFreeTail = pThis->iFreeHead = NIL_RTHT_INDEX;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pThis->iFreeHead = RTHT_GET_FREE_IDX(pFree);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            pThis->cCurAllocated++;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            Assert(pThis->cCurAllocated <= pThis->cCur);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             * Setup the entry and return.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            PRTHTENTRYCTX pEntry = (PRTHTENTRYCTX)pFree;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            pEntry->pvObj = pvObj;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            pEntry->pvCtx = pvCtx;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            *ph = i + pThis->uBase;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            rc = VINF_SUCCESS;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync         * Must expand the handle table, unless it's full.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync         */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        else if (pThis->cCur >= pThis->cMax)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            rc = VERR_NO_MORE_HANDLES;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            Assert(pThis->cCur == pThis->cCurAllocated);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             * Do we have to expand the 1st level table too?
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            uint32_t const iLevel1 = pThis->cCur / RTHT_LEVEL2_ENTRIES;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            uint32_t cLevel1 = iLevel1 >= pThis->cLevel1
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                             ? pThis->cLevel1 + PAGE_SIZE / sizeof(void *)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                             : 0;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (cLevel1 > pThis->cMax / RTHT_LEVEL2_ENTRIES)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                cLevel1 = pThis->cMax / RTHT_LEVEL2_ENTRIES;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            Assert(!cLevel1 || pThis->cMax / RTHT_LEVEL2_ENTRIES >= RTHT_LEVEL1_DYN_ALLOC_THRESHOLD);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /* leave the lock (never do fancy stuff from behind a spinlock). */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            rtHandleTableUnlock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             * Do the allocation(s).
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            rc = VERR_TRY_AGAIN;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            void **papvLevel1 = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (cLevel1)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                papvLevel1 = (void **)RTMemAlloc(sizeof(void *) * cLevel1);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                if (!papvLevel1)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    return VERR_NO_MEMORY;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            PRTHTENTRYCTX paTable = (PRTHTENTRYCTX)RTMemAlloc(sizeof(*paTable) * RTHT_LEVEL2_ENTRIES);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (!paTable)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                RTMemFree(papvLevel1);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                return VERR_NO_MEMORY;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /* re-enter the lock. */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            rtHandleTableLock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             * Insert the new bits, but be a bit careful as someone might have
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             * raced us expanding the table.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /* deal with the 1st level lookup expansion first */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (cLevel1)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                Assert(papvLevel1);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                if (cLevel1 > pThis->cLevel1)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    /* Replace the 1st level table. */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    memcpy(papvLevel1, pThis->papvLevel1, sizeof(void *) * pThis->cLevel1);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    memset(&papvLevel1[pThis->cLevel1], 0, sizeof(void *) * (cLevel1 - pThis->cLevel1));
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pThis->cLevel1 = cLevel1;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    void **papvTmp = pThis->papvLevel1;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pThis->papvLevel1 = papvLevel1;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    papvLevel1 = papvTmp;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                /* free the obsolete one (outside the lock of course) */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                rtHandleTableUnlock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                RTMemFree(papvLevel1);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                rtHandleTableLock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /* insert the table we allocated */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (pThis->cCur < pThis->cMax)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                uint32_t iLevel1New = pThis->cCur / RTHT_LEVEL2_ENTRIES;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pThis->papvLevel1[iLevel1New] = paTable;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                /* link all entries into a free list. */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                Assert(!(pThis->cCur % RTHT_LEVEL2_ENTRIES));
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                for (uint32_t i = 0; i < RTHT_LEVEL2_ENTRIES - 1; i++)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    RTHT_SET_FREE_IDX((PRTHTENTRYFREE)&paTable[i], i + 1 + pThis->cCur);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    paTable[i].pvCtx = (void *)~(uintptr_t)7;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                RTHT_SET_FREE_IDX((PRTHTENTRYFREE)&paTable[RTHT_LEVEL2_ENTRIES - 1], NIL_RTHT_INDEX);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                paTable[RTHT_LEVEL2_ENTRIES - 1].pvCtx = (void *)~(uintptr_t)7;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                /* join the free list with the other. */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                if (pThis->iFreeTail == NIL_RTHT_INDEX)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pThis->iFreeHead = pThis->cCur;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    PRTHTENTRYFREE pPrev = (PRTHTENTRYFREE)rtHandleTableLookupWithCtxIdx(pThis, pThis->iFreeTail);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    Assert(pPrev);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    RTHT_SET_FREE_IDX(pPrev, pThis->cCur);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pThis->iFreeTail = pThis->cCur + RTHT_LEVEL2_ENTRIES - 1;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pThis->cCur += RTHT_LEVEL2_ENTRIES;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                /* free the table (raced someone, and we lost). */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                rtHandleTableUnlock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                RTMemFree(paTable);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                rtHandleTableLock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            rc = VERR_TRY_AGAIN;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    } while (rc == VERR_TRY_AGAIN);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    rtHandleTableUnlock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    return rc;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync}
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsyncRTDECL(void *)  RTHandleTableLookupWithCtx(RTHANDLETABLE hHandleTable, uint32_t h, void *pvCtx)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync{
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* validate the input */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    PRTHANDLETABLEINT pThis = (PRTHANDLETABLEINT)hHandleTable;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertPtrReturn(pThis, NULL);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(pThis->u32Magic == RTHANDLETABLE_MAGIC, NULL);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(pThis->fFlags & RTHANDLETABLE_FLAGS_CONTEXT, NULL);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    void *pvObj = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* acquire the lock */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    RTSPINLOCKTMP Tmp;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    rtHandleTableLock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync     * Perform the lookup and retaining.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync     */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    PRTHTENTRYCTX pEntry = rtHandleTableLookupWithCtx(pThis, h);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    if (pEntry && pEntry->pvCtx == pvCtx)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        pvObj = pEntry->pvObj;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        if (!RTHT_IS_FREE(pvObj))
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (pThis->pfnRetain)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                int rc = pThis->pfnRetain(hHandleTable, pEntry->pvObj, pvCtx, pThis->pvRetainUser);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                if (RT_FAILURE(rc))
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pvObj = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            pvObj = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* release the lock */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    rtHandleTableUnlock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    return pvObj;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync}
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsyncRTDECL(void *)  RTHandleTableFreeWithCtx(RTHANDLETABLE hHandleTable, uint32_t h, void *pvCtx)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync{
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* validate the input */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    PRTHANDLETABLEINT pThis = (PRTHANDLETABLEINT)hHandleTable;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertPtrReturn(pThis, NULL);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(pThis->u32Magic == RTHANDLETABLE_MAGIC, NULL);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    AssertReturn(pThis->fFlags & RTHANDLETABLE_FLAGS_CONTEXT, NULL);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    void *pvObj = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* acquire the lock */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    RTSPINLOCKTMP Tmp;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    rtHandleTableLock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync     * Perform the lookup and retaining.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync     */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    PRTHTENTRYCTX pEntry = rtHandleTableLookupWithCtx(pThis, h);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    if (pEntry && pEntry->pvCtx == pvCtx)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        pvObj = pEntry->pvObj;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        if (!RTHT_IS_FREE(pvObj))
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (pThis->pfnRetain)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                int rc = pThis->pfnRetain(hHandleTable, pEntry->pvObj, pvCtx, pThis->pvRetainUser);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                if (RT_FAILURE(rc))
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pvObj = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            /*
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             * Link it into the free list.
cc66247640b520463f925a5533fc9e5de06aa982vboxsync             */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            if (pvObj)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pEntry->pvCtx = (void *)~(uintptr_t)7;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                PRTHTENTRYFREE pFree = (PRTHTENTRYFREE)pEntry;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                RTHT_SET_FREE_IDX(pFree, NIL_RTHT_INDEX);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                uint32_t const i = h - pThis->uBase;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                if (pThis->iFreeTail == NIL_RTHT_INDEX)
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pThis->iFreeHead = pThis->iFreeTail = i;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                {
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    PRTHTENTRYFREE pPrev = (PRTHTENTRYFREE)rtHandleTableLookupWithCtxIdx(pThis, pThis->iFreeTail);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    Assert(pPrev);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    RTHT_SET_FREE_IDX(pPrev, i);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                    pThis->iFreeTail = i;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                Assert(pThis->cCurAllocated > 0);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync                pThis->cCurAllocated--;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync        else
cc66247640b520463f925a5533fc9e5de06aa982vboxsync            pvObj = NULL;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    }
cc66247640b520463f925a5533fc9e5de06aa982vboxsync
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    /* release the lock */
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    rtHandleTableUnlock(pThis, &Tmp);
cc66247640b520463f925a5533fc9e5de06aa982vboxsync    return pvObj;
cc66247640b520463f925a5533fc9e5de06aa982vboxsync}
cc66247640b520463f925a5533fc9e5de06aa982vboxsync