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-rw-r--r--src/VBox/Runtime/common/vfs/vfsmemory.cpp943
1 files changed, 943 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/vfs/vfsmemory.cpp b/src/VBox/Runtime/common/vfs/vfsmemory.cpp
new file mode 100644
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--- /dev/null
+++ b/src/VBox/Runtime/common/vfs/vfsmemory.cpp
@@ -0,0 +1,943 @@
+/* $Id: vfsmemory.cpp $ */
+/** @file
+ * IPRT - Virtual File System, Memory Backed VFS.
+ */
+
+/*
+ * Copyright (C) 2010-2019 Oracle Corporation
+ *
+ * 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.
+ */
+
+
+/*********************************************************************************************************************************
+* Header Files *
+*********************************************************************************************************************************/
+#include "internal/iprt.h"
+#include <iprt/vfs.h>
+
+#include <iprt/asm.h>
+#include <iprt/assert.h>
+#include <iprt/err.h>
+#include <iprt/file.h>
+#include <iprt/list.h>
+#include <iprt/poll.h>
+#include <iprt/string.h>
+#include <iprt/vfslowlevel.h>
+
+
+
+/*********************************************************************************************************************************
+* Header Files *
+*********************************************************************************************************************************/
+#include "internal/iprt.h"
+#include <iprt/vfs.h>
+
+#include <iprt/err.h>
+#include <iprt/mem.h>
+
+
+/*********************************************************************************************************************************
+* Defined Constants And Macros *
+*********************************************************************************************************************************/
+/** The max extent size. */
+#define RTVFSMEM_MAX_EXTENT_SIZE _2M
+
+
+/*********************************************************************************************************************************
+* Structures and Typedefs *
+*********************************************************************************************************************************/
+
+/**
+ * Memory base object info.
+ */
+typedef struct RTVFSMEMBASE
+{
+ /** The basic object info. */
+ RTFSOBJINFO ObjInfo;
+} RTVFSMEMBASE;
+
+
+/**
+ * Memory file extent.
+ *
+ * This stores part of the file content.
+ */
+typedef struct RTVFSMEMEXTENT
+{
+ /** Extent list entry. */
+ RTLISTNODE Entry;
+ /** The offset of this extent within the file. */
+ uint64_t off;
+ /** The size of the this extent. */
+ uint32_t cb;
+ /** The data. */
+ uint8_t abData[1];
+} RTVFSMEMEXTENT;
+/** Pointer to a memory file extent. */
+typedef RTVFSMEMEXTENT *PRTVFSMEMEXTENT;
+
+/**
+ * Memory file.
+ */
+typedef struct RTVFSMEMFILE
+{
+ /** The base info. */
+ RTVFSMEMBASE Base;
+ /** The current file position. */
+ uint64_t offCurPos;
+ /** Pointer to the current file extent. */
+ PRTVFSMEMEXTENT pCurExt;
+ /** Linked list of file extents - RTVFSMEMEXTENT. */
+ RTLISTANCHOR ExtentHead;
+ /** The current extent size.
+ * This is slowly grown to RTVFSMEM_MAX_EXTENT_SIZE as the file grows. */
+ uint32_t cbExtent;
+} RTVFSMEMFILE;
+/** Pointer to a memory file. */
+typedef RTVFSMEMFILE *PRTVFSMEMFILE;
+
+
+
+/**
+ * @interface_method_impl{RTVFSOBJOPS,pfnClose}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_Close(void *pvThis)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+
+ /*
+ * Free the extent list.
+ */
+ PRTVFSMEMEXTENT pCur, pNext;
+ RTListForEachSafe(&pThis->ExtentHead, pCur, pNext, RTVFSMEMEXTENT, Entry)
+ {
+ pCur->off = RTFOFF_MAX;
+ pCur->cb = UINT32_MAX;
+ RTListNodeRemove(&pCur->Entry);
+ RTMemFree(pCur);
+ }
+ pThis->pCurExt = NULL;
+
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSOBJOPS,pfnQueryInfo}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_QueryInfo(void *pvThis, PRTFSOBJINFO pObjInfo, RTFSOBJATTRADD enmAddAttr)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+ switch (enmAddAttr)
+ {
+ case RTFSOBJATTRADD_NOTHING:
+ case RTFSOBJATTRADD_UNIX:
+ *pObjInfo = pThis->Base.ObjInfo;
+ return VINF_SUCCESS;
+
+ default:
+ return VERR_NOT_SUPPORTED;
+ }
+}
+
+
+/**
+ * The slow paths of rtVfsMemFile_LocateExtent.
+ *
+ * @copydoc rtVfsMemFile_LocateExtent
+ */
+static PRTVFSMEMEXTENT rtVfsMemFile_LocateExtentSlow(PRTVFSMEMFILE pThis, uint64_t off, bool *pfHit)
+{
+ /*
+ * Search from the start or the previously used extent. The heuristics
+ * are very very simple, but whatever.
+ */
+ PRTVFSMEMEXTENT pExtent = pThis->pCurExt;
+ if (!pExtent || off < pExtent->off)
+ {
+ /* Consider the last entry first (for writes). */
+ pExtent = RTListGetLast(&pThis->ExtentHead, RTVFSMEMEXTENT, Entry);
+ if (!pExtent)
+ {
+ *pfHit = false;
+ return NULL;
+ }
+ if (off - pExtent->off < pExtent->cb)
+ {
+ *pfHit = true;
+ pThis->pCurExt = pExtent;
+ return pExtent;
+ }
+
+ /* Otherwise, start from the head. */
+ pExtent = RTListGetFirst(&pThis->ExtentHead, RTVFSMEMEXTENT, Entry);
+ }
+
+ while (off - pExtent->off >= pExtent->cb)
+ {
+ Assert(pExtent->off <= off);
+ PRTVFSMEMEXTENT pNext = RTListGetNext(&pThis->ExtentHead, pExtent, RTVFSMEMEXTENT, Entry);
+ if ( !pNext
+ || pNext->off > off)
+ {
+ *pfHit = false;
+ return pNext;
+ }
+
+ pExtent = pNext;
+ }
+
+ *pfHit = true;
+ pThis->pCurExt = pExtent;
+ return pExtent;
+}
+
+
+/**
+ * Locates the extent covering the specified offset, or the one after it.
+ *
+ * @returns The closest extent. NULL if off is 0 and there are no extent
+ * covering byte 0 yet.
+ * @param pThis The memory file.
+ * @param off The offset (0-positive).
+ * @param pfHit Where to indicate whether the extent is a
+ * direct hit (@c true) or just a closest match
+ * (@c false).
+ */
+DECLINLINE(PRTVFSMEMEXTENT) rtVfsMemFile_LocateExtent(PRTVFSMEMFILE pThis, uint64_t off, bool *pfHit)
+{
+ /*
+ * The most likely case is that we're hitting the extent we used in the
+ * previous access or the one immediately following it.
+ */
+ PRTVFSMEMEXTENT pExtent = pThis->pCurExt;
+ if (!pExtent)
+ return rtVfsMemFile_LocateExtentSlow(pThis, off, pfHit);
+
+ if (off - pExtent->off >= pExtent->cb)
+ {
+ pExtent = RTListGetNext(&pThis->ExtentHead, pExtent, RTVFSMEMEXTENT, Entry);
+ if ( !pExtent
+ || off - pExtent->off >= pExtent->cb)
+ return rtVfsMemFile_LocateExtentSlow(pThis, off, pfHit);
+ pThis->pCurExt = pExtent;
+ }
+
+ *pfHit = true;
+ return pExtent;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSIOSTREAMOPS,pfnRead}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_Read(void *pvThis, RTFOFF off, PCRTSGBUF pSgBuf, bool fBlocking, size_t *pcbRead)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+
+ Assert(pSgBuf->cSegs == 1);
+ NOREF(fBlocking);
+
+ /*
+ * Find the current position and check if it's within the file.
+ */
+ uint64_t offUnsigned = off < 0 ? pThis->offCurPos : (uint64_t)off;
+ if (offUnsigned >= (uint64_t)pThis->Base.ObjInfo.cbObject)
+ {
+ if (pcbRead)
+ {
+ *pcbRead = 0;
+ pThis->offCurPos = offUnsigned;
+ return VINF_EOF;
+ }
+ return VERR_EOF;
+ }
+
+ size_t cbLeftToRead;
+ if (offUnsigned + pSgBuf->paSegs[0].cbSeg > (uint64_t)pThis->Base.ObjInfo.cbObject)
+ {
+ if (!pcbRead)
+ return VERR_EOF;
+ *pcbRead = cbLeftToRead = (size_t)((uint64_t)pThis->Base.ObjInfo.cbObject - offUnsigned);
+ }
+ else
+ {
+ cbLeftToRead = pSgBuf->paSegs[0].cbSeg;
+ if (pcbRead)
+ *pcbRead = cbLeftToRead;
+ }
+
+ /*
+ * Ok, we've got a valid stretch within the file. Do the reading.
+ */
+ if (cbLeftToRead > 0)
+ {
+ uint8_t *pbDst = (uint8_t *)pSgBuf->paSegs[0].pvSeg;
+ bool fHit;
+ PRTVFSMEMEXTENT pExtent = rtVfsMemFile_LocateExtent(pThis, offUnsigned, &fHit);
+ for (;;)
+ {
+ size_t cbThisRead;
+
+ /*
+ * Do we hit an extent covering the current file surface?
+ */
+ if (fHit)
+ {
+ /* Yes, copy the data. */
+ Assert(offUnsigned - pExtent->off < pExtent->cb);
+ size_t const offExtent = (size_t)(offUnsigned - pExtent->off);
+ cbThisRead = pExtent->cb - offExtent;
+ if (cbThisRead >= cbLeftToRead)
+ cbThisRead = cbLeftToRead;
+
+ memcpy(pbDst, &pExtent->abData[offUnsigned - pExtent->off], cbThisRead);
+
+ offUnsigned += cbThisRead;
+ cbLeftToRead -= cbThisRead;
+ if (!cbLeftToRead)
+ break;
+ pbDst += cbThisRead;
+
+ /* Advance, looping immediately if not sparse. */
+ PRTVFSMEMEXTENT pNext = RTListGetNext(&pThis->ExtentHead, pExtent, RTVFSMEMEXTENT, Entry);
+ if ( pNext
+ && pNext->off == pExtent->off + pExtent->cb)
+ {
+ pExtent = pNext;
+ continue;
+ }
+
+ Assert(!pNext || pNext->off > pExtent->off);
+ pExtent = pNext;
+ fHit = false;
+ }
+ else
+ Assert(!pExtent || pExtent->off > offUnsigned);
+
+ /*
+ * No extent of this portion (sparse file) - Read zeros.
+ */
+ if ( !pExtent
+ || offUnsigned + cbLeftToRead <= pExtent->off)
+ cbThisRead = cbLeftToRead;
+ else
+ cbThisRead = (size_t)(pExtent->off - offUnsigned);
+
+ RT_BZERO(pbDst, cbThisRead);
+
+ offUnsigned += cbThisRead;
+ cbLeftToRead -= cbThisRead;
+ if (!cbLeftToRead)
+ break;
+ pbDst += cbThisRead;
+
+ /* Go on and read content from the next extent. */
+ fHit = true;
+ }
+ }
+
+ pThis->offCurPos = offUnsigned;
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * Allocates a new extent covering the ground at @a offUnsigned.
+ *
+ * @returns Pointer to the new extent on success, NULL if we're out of memory.
+ * @param pThis The memory file.
+ * @param offUnsigned The location to allocate the extent at.
+ * @param cbToWrite The number of bytes we're interested in writing
+ * starting at @a offUnsigned.
+ * @param pNext The extention after @a offUnsigned. NULL if
+ * none, i.e. we're allocating space at the end of
+ * the file.
+ */
+static PRTVFSMEMEXTENT rtVfsMemFile_AllocExtent(PRTVFSMEMFILE pThis, uint64_t offUnsigned, size_t cbToWrite,
+ PRTVFSMEMEXTENT pNext)
+{
+ /*
+ * Adjust the extent size if we haven't reached the max size yet.
+ */
+ if (pThis->cbExtent != RTVFSMEM_MAX_EXTENT_SIZE)
+ {
+ if (cbToWrite >= RTVFSMEM_MAX_EXTENT_SIZE)
+ pThis->cbExtent = RTVFSMEM_MAX_EXTENT_SIZE;
+ else if (!RTListIsEmpty(&pThis->ExtentHead))
+ {
+ uint32_t cbNextExtent = pThis->cbExtent;
+ if (RT_IS_POWER_OF_TWO(cbNextExtent))
+ cbNextExtent *= 2;
+ else
+ {
+ /* Make it a power of two (seeRTVfsMemorizeIoStreamAsFile). */
+ cbNextExtent = _4K;
+ while (cbNextExtent < pThis->cbExtent)
+ cbNextExtent *= 2;
+ }
+ if (((pThis->Base.ObjInfo.cbAllocated + cbNextExtent) & (cbNextExtent - 1)) == 0)
+ pThis->cbExtent = cbNextExtent;
+ }
+ }
+
+ /*
+ * Figure out the size and position of the extent we're adding.
+ */
+ uint64_t offExtent = offUnsigned & ~(uint64_t)(pThis->cbExtent - 1);
+ uint32_t cbExtent = pThis->cbExtent;
+
+ PRTVFSMEMEXTENT pPrev = pNext
+ ? RTListGetPrev(&pThis->ExtentHead, pNext, RTVFSMEMEXTENT, Entry)
+ : RTListGetLast(&pThis->ExtentHead, RTVFSMEMEXTENT, Entry);
+ uint64_t const offPrev = pPrev ? pPrev->off + pPrev->cb : 0;
+ if (offExtent < offPrev)
+ offExtent = offPrev;
+
+ if (pNext)
+ {
+ uint64_t cbMaxExtent = pNext->off - offExtent;
+ if (cbMaxExtent < cbExtent)
+ cbExtent = (uint32_t)cbMaxExtent;
+ }
+
+ /*
+ * Allocate, initialize and insert the new extent.
+ */
+ PRTVFSMEMEXTENT pNew = (PRTVFSMEMEXTENT)RTMemAllocZ(RT_UOFFSETOF_DYN(RTVFSMEMEXTENT, abData[cbExtent]));
+ if (pNew)
+ {
+ pNew->off = offExtent;
+ pNew->cb = cbExtent;
+ if (pPrev)
+ RTListNodeInsertAfter(&pPrev->Entry, &pNew->Entry);
+ else
+ RTListPrepend(&pThis->ExtentHead, &pNew->Entry);
+
+ pThis->Base.ObjInfo.cbAllocated += cbExtent;
+ }
+ /** @todo retry with minimum size. */
+
+ return pNew;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSIOSTREAMOPS,pfnWrite}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_Write(void *pvThis, RTFOFF off, PCRTSGBUF pSgBuf, bool fBlocking, size_t *pcbWritten)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+
+ Assert(pSgBuf->cSegs == 1);
+ NOREF(fBlocking);
+
+ /*
+ * Validate the write and set up the write loop.
+ */
+ size_t cbLeftToWrite = pSgBuf->paSegs[0].cbSeg;
+ if (!cbLeftToWrite)
+ return VINF_SUCCESS; /* pcbWritten is already 0. */
+ uint64_t offUnsigned = off < 0 ? pThis->offCurPos : (uint64_t)off;
+ if (offUnsigned + cbLeftToWrite >= (uint64_t)RTFOFF_MAX)
+ return VERR_OUT_OF_RANGE;
+
+ int rc = VINF_SUCCESS;
+ uint8_t const *pbSrc = (uint8_t const *)pSgBuf->paSegs[0].pvSeg;
+ bool fHit;
+ PRTVFSMEMEXTENT pExtent = rtVfsMemFile_LocateExtent(pThis, offUnsigned, &fHit);
+ for (;;)
+ {
+ /*
+ * If we didn't hit an extent, allocate one (unless it's all zeros).
+ */
+ if (!fHit)
+ {
+ Assert(!pExtent || pExtent->off > offUnsigned);
+
+ /* Skip leading zeros if there is a whole bunch of them. */
+ uint8_t const *pbSrcNZ = (uint8_t const *)ASMMemFirstNonZero(pbSrc, cbLeftToWrite);
+ size_t cbZeros = pbSrcNZ ? pbSrcNZ - pbSrc : cbLeftToWrite;
+ if (cbZeros)
+ {
+ uint64_t const cbToNext = pExtent ? pExtent->off - offUnsigned : UINT64_MAX;
+ if (cbZeros > cbToNext)
+ cbZeros = (size_t)cbToNext;
+ offUnsigned += cbZeros;
+ cbLeftToWrite -= cbZeros;
+ if (!cbLeftToWrite)
+ break;
+
+ Assert(!pExtent || offUnsigned <= pExtent->off);
+ if (pExtent && pExtent->off == offUnsigned)
+ {
+ fHit = true;
+ continue;
+ }
+ }
+
+ fHit = true;
+ pExtent = rtVfsMemFile_AllocExtent(pThis, offUnsigned, cbLeftToWrite, pExtent);
+ if (!pExtent)
+ {
+ rc = VERR_NO_MEMORY;
+ break;
+ }
+ }
+ Assert(offUnsigned - pExtent->off < pExtent->cb);
+
+ /*
+ * Copy the source data into the current extent.
+ */
+ uint32_t const offDst = (uint32_t)(offUnsigned - pExtent->off);
+ uint32_t cbThisWrite = pExtent->cb - offDst;
+ if (cbThisWrite > cbLeftToWrite)
+ cbThisWrite = (uint32_t)cbLeftToWrite;
+ memcpy(&pExtent->abData[offDst], pbSrc, cbThisWrite);
+
+ offUnsigned += cbThisWrite;
+ cbLeftToWrite -= cbThisWrite;
+ if (!cbLeftToWrite)
+ break;
+ pbSrc += cbThisWrite;
+ Assert(offUnsigned == pExtent->off + pExtent->cb);
+
+ /*
+ * Advance to the next extent (emulate the lookup).
+ */
+ pExtent = RTListGetNext(&pThis->ExtentHead, pExtent, RTVFSMEMEXTENT, Entry);
+ fHit = pExtent && (offUnsigned - pExtent->off < pExtent->cb);
+ }
+
+ /*
+ * Update the state, set return value and return.
+ * Note! There must be no alternative exit path from the loop above.
+ */
+ pThis->offCurPos = offUnsigned;
+ if ((uint64_t)pThis->Base.ObjInfo.cbObject < offUnsigned)
+ pThis->Base.ObjInfo.cbObject = offUnsigned;
+
+ if (pcbWritten)
+ *pcbWritten = pSgBuf->paSegs[0].cbSeg - cbLeftToWrite;
+ return rc;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSIOSTREAMOPS,pfnFlush}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_Flush(void *pvThis)
+{
+ NOREF(pvThis);
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSIOSTREAMOPS,pfnTell}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_Tell(void *pvThis, PRTFOFF poffActual)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+ *poffActual = pThis->offCurPos;
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSOBJSETOPS,pfnMode}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_SetMode(void *pvThis, RTFMODE fMode, RTFMODE fMask)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+ pThis->Base.ObjInfo.Attr.fMode = (pThis->Base.ObjInfo.Attr.fMode & ~fMask) | fMode;
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSOBJSETOPS,pfnSetTimes}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_SetTimes(void *pvThis, PCRTTIMESPEC pAccessTime, PCRTTIMESPEC pModificationTime,
+ PCRTTIMESPEC pChangeTime, PCRTTIMESPEC pBirthTime)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+
+ if (pAccessTime)
+ pThis->Base.ObjInfo.AccessTime = *pAccessTime;
+ if (pModificationTime)
+ pThis->Base.ObjInfo.ModificationTime = *pModificationTime;
+ if (pChangeTime)
+ pThis->Base.ObjInfo.ChangeTime = *pChangeTime;
+ if (pBirthTime)
+ pThis->Base.ObjInfo.BirthTime = *pBirthTime;
+
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSOBJSETOPS,pfnSetOwner}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_SetOwner(void *pvThis, RTUID uid, RTGID gid)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+
+ if (uid != NIL_RTUID)
+ pThis->Base.ObjInfo.Attr.u.Unix.uid = uid;
+ if (gid != NIL_RTUID)
+ pThis->Base.ObjInfo.Attr.u.Unix.gid = gid;
+
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSFILEOPS,pfnSeek}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_Seek(void *pvThis, RTFOFF offSeek, unsigned uMethod, PRTFOFF poffActual)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+
+ /*
+ * Seek relative to which position.
+ */
+ uint64_t offWrt;
+ switch (uMethod)
+ {
+ case RTFILE_SEEK_BEGIN:
+ offWrt = 0;
+ break;
+
+ case RTFILE_SEEK_CURRENT:
+ offWrt = pThis->offCurPos;
+ break;
+
+ case RTFILE_SEEK_END:
+ offWrt = pThis->Base.ObjInfo.cbObject;
+ break;
+
+ default:
+ return VERR_INTERNAL_ERROR_5;
+ }
+
+ /*
+ * Calc new position, take care to stay within RTFOFF type bounds.
+ */
+ uint64_t offNew;
+ if (offSeek == 0)
+ offNew = offWrt;
+ else if (offSeek > 0)
+ {
+ offNew = offWrt + offSeek;
+ if ( offNew < offWrt
+ || offNew > RTFOFF_MAX)
+ offNew = RTFOFF_MAX;
+ }
+ else if ((uint64_t)-offSeek < offWrt)
+ offNew = offWrt + offSeek;
+ else
+ offNew = 0;
+
+ /*
+ * Update the state and set return value.
+ */
+ if ( pThis->pCurExt
+ && pThis->pCurExt->off - offNew >= pThis->pCurExt->cb)
+ pThis->pCurExt = NULL;
+ pThis->offCurPos = offNew;
+
+ *poffActual = offNew;
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSFILEOPS,pfnQuerySize}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_QuerySize(void *pvThis, uint64_t *pcbFile)
+{
+ PRTVFSMEMFILE pThis = (PRTVFSMEMFILE)pvThis;
+ *pcbFile = pThis->Base.ObjInfo.cbObject;
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSFILEOPS,pfnSetSize}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_SetSize(void *pvThis, uint64_t cbFile, uint32_t fFlags)
+{
+ NOREF(pvThis); NOREF(cbFile); NOREF(fFlags);
+ AssertMsgFailed(("Lucky you! You get to implement this (or bug bird about it).\n"));
+ return VERR_NOT_IMPLEMENTED;
+}
+
+
+/**
+ * @interface_method_impl{RTVFSFILEOPS,pfnQueryMaxSize}
+ */
+static DECLCALLBACK(int) rtVfsMemFile_QueryMaxSize(void *pvThis, uint64_t *pcbMax)
+{
+ RT_NOREF(pvThis);
+ *pcbMax = ~(size_t)0 >> 1;
+ return VINF_SUCCESS;
+}
+
+
+/**
+ * Memory file operations.
+ */
+DECL_HIDDEN_CONST(const RTVFSFILEOPS) g_rtVfsMemFileOps =
+{
+ { /* Stream */
+ { /* Obj */
+ RTVFSOBJOPS_VERSION,
+ RTVFSOBJTYPE_FILE,
+ "MemFile",
+ rtVfsMemFile_Close,
+ rtVfsMemFile_QueryInfo,
+ RTVFSOBJOPS_VERSION
+ },
+ RTVFSIOSTREAMOPS_VERSION,
+ RTVFSIOSTREAMOPS_FEAT_NO_SG,
+ rtVfsMemFile_Read,
+ rtVfsMemFile_Write,
+ rtVfsMemFile_Flush,
+ NULL /*PollOne*/,
+ rtVfsMemFile_Tell,
+ NULL /*Skip*/,
+ NULL /*ZeroFill*/,
+ RTVFSIOSTREAMOPS_VERSION,
+ },
+ RTVFSFILEOPS_VERSION,
+ /*RTVFSIOFILEOPS_FEAT_NO_AT_OFFSET*/ 0,
+ { /* ObjSet */
+ RTVFSOBJSETOPS_VERSION,
+ RT_UOFFSETOF(RTVFSFILEOPS, ObjSet) - RT_UOFFSETOF(RTVFSFILEOPS, Stream.Obj),
+ rtVfsMemFile_SetMode,
+ rtVfsMemFile_SetTimes,
+ rtVfsMemFile_SetOwner,
+ RTVFSOBJSETOPS_VERSION
+ },
+ rtVfsMemFile_Seek,
+ rtVfsMemFile_QuerySize,
+ rtVfsMemFile_SetSize,
+ rtVfsMemFile_QueryMaxSize,
+ RTVFSFILEOPS_VERSION
+};
+
+
+/**
+ * Initialize the RTVFSMEMFILE::Base.ObjInfo specific members.
+ *
+ * @param pObjInfo The object info to init.
+ * @param cbObject The object size set.
+ */
+static void rtVfsMemInitObjInfo(PRTFSOBJINFO pObjInfo, uint64_t cbObject)
+{
+ pObjInfo->cbObject = cbObject;
+ pObjInfo->cbAllocated = cbObject;
+ pObjInfo->Attr.fMode = RTFS_DOS_NT_NORMAL | RTFS_TYPE_FILE | RTFS_UNIX_IRWXU;
+ pObjInfo->Attr.enmAdditional = RTFSOBJATTRADD_UNIX;
+ pObjInfo->Attr.u.Unix.uid = NIL_RTUID;
+ pObjInfo->Attr.u.Unix.gid = NIL_RTGID;
+ pObjInfo->Attr.u.Unix.cHardlinks = 1;
+ pObjInfo->Attr.u.Unix.INodeIdDevice = 0;
+ pObjInfo->Attr.u.Unix.INodeId = 0;
+ pObjInfo->Attr.u.Unix.fFlags = 0;
+ pObjInfo->Attr.u.Unix.GenerationId = 0;
+ pObjInfo->Attr.u.Unix.Device = 0;
+ RTTimeNow(&pObjInfo->AccessTime);
+ pObjInfo->ModificationTime = pObjInfo->AccessTime;
+ pObjInfo->ChangeTime = pObjInfo->AccessTime;
+ pObjInfo->BirthTime = pObjInfo->AccessTime;
+}
+
+
+/**
+ * Initialize the RTVFSMEMFILE specific members.
+ *
+ * @param pThis The memory file to initialize.
+ * @param cbObject The object size for estimating extent size.
+ * @param fFlags The user specified flags.
+ */
+static void rtVfsMemFileInit(PRTVFSMEMFILE pThis, RTFOFF cbObject, uint32_t fFlags)
+{
+ pThis->offCurPos = 0;
+ pThis->pCurExt = NULL;
+ RTListInit(&pThis->ExtentHead);
+ if (cbObject <= 0)
+ pThis->cbExtent = _4K;
+ else if (cbObject < RTVFSMEM_MAX_EXTENT_SIZE)
+ pThis->cbExtent = fFlags & RTFILE_O_WRITE ? _4K : cbObject;
+ else
+ pThis->cbExtent = RTVFSMEM_MAX_EXTENT_SIZE;
+}
+
+
+/**
+ * Rewinds the file to position 0 and clears the WRITE flag if necessary.
+ *
+ * @param pThis The memory file instance.
+ * @param fFlags The user specified flags.
+ */
+static void rtVfsMemFileResetAndFixWriteFlag(PRTVFSMEMFILE pThis, uint32_t fFlags)
+{
+ pThis->pCurExt = RTListGetFirst(&pThis->ExtentHead, RTVFSMEMEXTENT, Entry);
+ pThis->offCurPos = 0;
+
+ if (!(fFlags & RTFILE_O_WRITE))
+ {
+ /** @todo clear RTFILE_O_WRITE from the resulting. */
+ }
+}
+
+
+RTDECL(int) RTVfsMemFileCreate(RTVFSIOSTREAM hVfsIos, size_t cbEstimate, PRTVFSFILE phVfsFile)
+{
+ /*
+ * Create a memory file instance and set the extension size according to the
+ * buffer size. Add the WRITE flag so we can use normal write APIs for
+ * copying the buffer.
+ */
+ RTVFSFILE hVfsFile;
+ PRTVFSMEMFILE pThis;
+ int rc = RTVfsNewFile(&g_rtVfsMemFileOps, sizeof(*pThis), RTFILE_O_READ | RTFILE_O_WRITE, NIL_RTVFS, NIL_RTVFSLOCK,
+ &hVfsFile, (void **)&pThis);
+ if (RT_SUCCESS(rc))
+ {
+ rtVfsMemInitObjInfo(&pThis->Base.ObjInfo, 0);
+ rtVfsMemFileInit(pThis, cbEstimate, RTFILE_O_READ | RTFILE_O_WRITE);
+
+ if (hVfsIos != NIL_RTVFSIOSTREAM)
+ {
+ RTVFSIOSTREAM hVfsIosDst = RTVfsFileToIoStream(hVfsFile);
+ rc = RTVfsUtilPumpIoStreams(hVfsIos, hVfsIosDst, pThis->cbExtent);
+ RTVfsIoStrmRelease(hVfsIosDst);
+ }
+
+ if (RT_SUCCESS(rc))
+ {
+ *phVfsFile = hVfsFile;
+ return VINF_SUCCESS;
+ }
+
+ RTVfsFileRelease(hVfsFile);
+ }
+ return rc;
+}
+
+
+RTDECL(int) RTVfsMemIoStrmCreate(RTVFSIOSTREAM hVfsIos, size_t cbEstimate, PRTVFSIOSTREAM phVfsIos)
+{
+ RTVFSFILE hVfsFile;
+ int rc = RTVfsMemFileCreate(hVfsIos, cbEstimate, &hVfsFile);
+ if (RT_SUCCESS(rc))
+ {
+ *phVfsIos = RTVfsFileToIoStream(hVfsFile);
+ AssertStmt(*phVfsIos != NIL_RTVFSIOSTREAM, rc = VERR_INTERNAL_ERROR_2);
+ RTVfsFileRelease(hVfsFile);
+ }
+ return rc;
+}
+
+
+RTDECL(int) RTVfsFileFromBuffer(uint32_t fFlags, void const *pvBuf, size_t cbBuf, PRTVFSFILE phVfsFile)
+{
+ /*
+ * Create a memory file instance and set the extension size according to the
+ * buffer size. Add the WRITE flag so we can use normal write APIs for
+ * copying the buffer.
+ */
+ RTVFSFILE hVfsFile;
+ PRTVFSMEMFILE pThis;
+ int rc = RTVfsNewFile(&g_rtVfsMemFileOps, sizeof(*pThis), fFlags | RTFILE_O_WRITE, NIL_RTVFS, NIL_RTVFSLOCK,
+ &hVfsFile, (void **)&pThis);
+ if (RT_SUCCESS(rc))
+ {
+ rtVfsMemInitObjInfo(&pThis->Base.ObjInfo, cbBuf);
+ rtVfsMemFileInit(pThis, cbBuf, fFlags);
+
+ /*
+ * Copy the buffer and reposition the file pointer to the start.
+ */
+ rc = RTVfsFileWrite(hVfsFile, pvBuf, cbBuf, NULL);
+ if (RT_SUCCESS(rc))
+ {
+ rtVfsMemFileResetAndFixWriteFlag(pThis, fFlags);
+ *phVfsFile = hVfsFile;
+ return VINF_SUCCESS;
+ }
+ RTVfsFileRelease(hVfsFile);
+ }
+ return rc;
+}
+
+
+RTDECL(int) RTVfsIoStrmFromBuffer(uint32_t fFlags, void const *pvBuf, size_t cbBuf, PRTVFSIOSTREAM phVfsIos)
+{
+ RTVFSFILE hVfsFile;
+ int rc = RTVfsFileFromBuffer(fFlags, pvBuf, cbBuf, &hVfsFile);
+ if (RT_SUCCESS(rc))
+ {
+ *phVfsIos = RTVfsFileToIoStream(hVfsFile);
+ RTVfsFileRelease(hVfsFile);
+ }
+ return rc;
+}
+
+
+RTDECL(int) RTVfsMemorizeIoStreamAsFile(RTVFSIOSTREAM hVfsIos, uint32_t fFlags, PRTVFSFILE phVfsFile)
+{
+ /*
+ * Create a memory file instance and try set the extension size to match
+ * the length of the I/O stream.
+ */
+ RTFSOBJINFO ObjInfo;
+ int rc = RTVfsIoStrmQueryInfo(hVfsIos, &ObjInfo, RTFSOBJATTRADD_UNIX);
+ if (RT_SUCCESS(rc))
+ {
+ RTVFSFILE hVfsFile;
+ PRTVFSMEMFILE pThis;
+ rc = RTVfsNewFile(&g_rtVfsMemFileOps, sizeof(*pThis), fFlags | RTFILE_O_WRITE, NIL_RTVFS, NIL_RTVFSLOCK,
+ &hVfsFile, (void **)&pThis);
+ if (RT_SUCCESS(rc))
+ {
+ pThis->Base.ObjInfo = ObjInfo;
+ rtVfsMemFileInit(pThis, ObjInfo.cbObject, fFlags);
+
+ /*
+ * Copy the stream.
+ */
+ RTVFSIOSTREAM hVfsIosDst = RTVfsFileToIoStream(hVfsFile);
+ rc = RTVfsUtilPumpIoStreams(hVfsIos, hVfsIosDst, pThis->cbExtent);
+ RTVfsIoStrmRelease(hVfsIosDst);
+ if (RT_SUCCESS(rc))
+ {
+ rtVfsMemFileResetAndFixWriteFlag(pThis, fFlags);
+ *phVfsFile = hVfsFile;
+ return VINF_SUCCESS;
+ }
+ RTVfsFileRelease(hVfsFile);
+ }
+ }
+ return rc;
+}
+