Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 934 insertions, 0 deletions

diff --git a/src/VBox/Runtime/r3/posix/fileio-posix.cpp b/src/VBox/Runtime/r3/posix/fileio-posix.cpp
new file mode 100644
index 00000000..cd7d238f
--- /dev/null
+++ b/src/VBox/Runtime/r3/posix/fileio-posix.cpp
@@ -0,0 +1,934 @@
+/* $Id: fileio-posix.cpp $ */
+/** @file
+ * IPRT - File I/O, POSIX, Part 1.
+ */
+
+/*
+ * Copyright (C) 2006-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * 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, in version 3 of the
+ * License.
+ *
+ * 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, see <https://www.gnu.org/licenses>.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
+ * in the VirtualBox 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.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#define LOG_GROUP RTLOGGROUP_FILE
+
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#ifdef _MSC_VER
+# include <io.h>
+# include <stdio.h>
+#else
+# include <unistd.h>
+# include <sys/time.h>
+#endif
+#ifdef RT_OS_LINUX
+# include <sys/file.h>
+#endif
+#if defined(RT_OS_OS2) && (!defined(__INNOTEK_LIBC__) || __INNOTEK_LIBC__ < 0x006)
+# include <io.h>
+#endif
+#if defined(RT_OS_DARWIN) || defined(RT_OS_FREEBSD)
+# include <sys/disk.h>
+#endif
+#ifdef RT_OS_SOLARIS
+# include <stropts.h>
+# include <sys/dkio.h>
+# include <sys/vtoc.h>
+#endif /* RT_OS_SOLARIS */
+
+#include <iprt/file.h>
+#include <iprt/path.h>
+#include <iprt/assert.h>
+#include <iprt/string.h>
+#include <iprt/err.h>
+#include <iprt/log.h>
+#include <iprt/thread.h>
+#include "internal/file.h"
+#include "internal/fs.h"
+#include "internal/path.h"
+
+
+
+/*********************************************************************************************************************************
+*   Defined Constants And Macros                                                                                                 *
+*********************************************************************************************************************************/
+/** Default file permissions for newly created files. */
+#if defined(S_IRUSR) && defined(S_IWUSR)
+# define RT_FILE_PERMISSION  (S_IRUSR | S_IWUSR)
+#else
+# define RT_FILE_PERMISSION  (00600)
+#endif
+
+
+/*********************************************************************************************************************************
+*   Defined Constants And Macros                                                                                                 *
+*********************************************************************************************************************************/
+#ifdef O_CLOEXEC
+static int volatile g_fHave_O_CLOEXEC = 0; /* {-1,0,1}; since Linux 2.6.23 */
+#endif
+
+
+
+RTDECL(bool) RTFileExists(const char *pszPath)
+{
+    bool fRc = false;
+    char const *pszNativePath;
+    int rc = rtPathToNative(&pszNativePath, pszPath, NULL);
+    if (RT_SUCCESS(rc))
+    {
+        struct stat s;
+        fRc = !stat(pszNativePath, &s)
+            && S_ISREG(s.st_mode);
+
+        rtPathFreeNative(pszNativePath, pszPath);
+    }
+
+    LogFlow(("RTFileExists(%p={%s}): returns %RTbool\n", pszPath, pszPath, fRc));
+    return fRc;
+}
+
+
+#ifdef O_CLOEXEC
+/** Worker for RTFileOpenEx that detects whether the kernel supports
+ *  O_CLOEXEC or not, setting g_fHave_O_CLOEXEC to 1 or -1 accordingly. */
+static int rtFileOpenExDetectCloExecSupport(void)
+{
+    /*
+     * Open /dev/null with O_CLOEXEC and see if FD_CLOEXEC is set or not.
+     */
+    int fHave_O_CLOEXEC = -1;
+    int fd = open("/dev/null", O_RDONLY | O_CLOEXEC, 0);
+    if (fd >= 0)
+    {
+        int fFlags = fcntl(fd, F_GETFD, 0);
+        fHave_O_CLOEXEC = fFlags > 0 && (fFlags & FD_CLOEXEC) ? 1 : -1;
+        close(fd);
+    }
+    else
+        AssertMsg(errno == EINVAL, ("%d\n", errno));
+    g_fHave_O_CLOEXEC = fHave_O_CLOEXEC;
+    return fHave_O_CLOEXEC;
+}
+#endif
+
+
+RTR3DECL(int) RTFileOpen(PRTFILE pFile, const char *pszFilename, uint64_t fOpen)
+{
+    return RTFileOpenEx(pszFilename, fOpen, pFile, NULL);
+}
+
+
+RTDECL(int)  RTFileOpenEx(const char *pszFilename, uint64_t fOpen, PRTFILE phFile, PRTFILEACTION penmActionTaken)
+{
+    /*
+     * Validate input.
+     */
+    AssertPtrReturn(phFile, VERR_INVALID_POINTER);
+    *phFile = NIL_RTFILE;
+    if (penmActionTaken)
+        *penmActionTaken = RTFILEACTION_INVALID;
+    AssertPtrReturn(pszFilename, VERR_INVALID_POINTER);
+
+    /*
+     * Merge forced open flags and validate them.
+     */
+    int rc = rtFileRecalcAndValidateFlags(&fOpen);
+    if (RT_FAILURE(rc))
+        return rc;
+#ifndef O_NONBLOCK
+    AssertReturn(!(fOpen & RTFILE_O_NON_BLOCK), VERR_INVALID_FLAGS);
+#endif
+#if defined(RT_OS_OS2) /* Cannot delete open files on OS/2. */
+    AssertReturn(!(fOpen & RTFILE_O_TEMP_AUTO_DELETE), VERR_NOT_SUPPORTED);
+#endif
+
+    /*
+     * Calculate open mode flags.
+     */
+    int fOpenMode = 0;
+#ifdef O_BINARY
+    fOpenMode |= O_BINARY;              /* (pc) */
+#endif
+#ifdef O_LARGEFILE
+    fOpenMode |= O_LARGEFILE;           /* (linux, solaris) */
+#endif
+#ifdef O_NOINHERIT
+    if (!(fOpen & RTFILE_O_INHERIT))
+        fOpenMode |= O_NOINHERIT;
+#endif
+#ifdef O_CLOEXEC
+    int fHave_O_CLOEXEC = g_fHave_O_CLOEXEC;
+    if (   !(fOpen & RTFILE_O_INHERIT)
+        && (   fHave_O_CLOEXEC > 0
+            || (   fHave_O_CLOEXEC == 0
+                && (fHave_O_CLOEXEC = rtFileOpenExDetectCloExecSupport()) > 0)))
+        fOpenMode |= O_CLOEXEC;
+#endif
+#ifdef O_NONBLOCK
+    if (fOpen & RTFILE_O_NON_BLOCK)
+        fOpenMode |= O_NONBLOCK;
+#endif
+#ifdef O_SYNC
+    if (fOpen & RTFILE_O_WRITE_THROUGH)
+        fOpenMode |= O_SYNC;
+#endif
+#if defined(O_DIRECT) && defined(RT_OS_LINUX)
+    /* O_DIRECT is mandatory to get async I/O working on Linux. */
+    if (fOpen & RTFILE_O_ASYNC_IO)
+        fOpenMode |= O_DIRECT;
+#endif
+#if defined(O_DIRECT) && (defined(RT_OS_LINUX) || defined(RT_OS_FREEBSD) || defined(RT_OS_NETBSD))
+    /* Disable the kernel cache. */
+    if (fOpen & RTFILE_O_NO_CACHE)
+        fOpenMode |= O_DIRECT;
+#endif
+
+    /* create/truncate file */
+    switch (fOpen & RTFILE_O_ACTION_MASK)
+    {
+        case RTFILE_O_OPEN:             break;
+        case RTFILE_O_OPEN_CREATE:      fOpenMode |= O_CREAT; break;
+        case RTFILE_O_CREATE:           fOpenMode |= O_CREAT | O_EXCL; break;
+        case RTFILE_O_CREATE_REPLACE:   fOpenMode |= O_CREAT | O_TRUNC; break; /** @todo replacing needs fixing, this is *not* a 1:1 mapping! */
+        default:
+            AssertMsgFailed(("fOpen=%#llx\n", fOpen));
+            fOpen = (fOpen & ~RTFILE_O_ACTION_MASK) | RTFILE_O_OPEN;
+            break;
+
+    }
+    if (   (fOpen & RTFILE_O_TRUNCATE)
+        && (fOpen & RTFILE_O_ACTION_MASK) != RTFILE_O_CREATE)
+        fOpenMode |= O_TRUNC;
+
+    switch (fOpen & RTFILE_O_ACCESS_MASK)
+    {
+        case RTFILE_O_READ:
+            fOpenMode |= O_RDONLY; /* RTFILE_O_APPEND is ignored. */
+            break;
+        case RTFILE_O_WRITE:
+            fOpenMode |= fOpen & RTFILE_O_APPEND ? O_APPEND | O_WRONLY : O_WRONLY;
+            break;
+        case RTFILE_O_READWRITE:
+            fOpenMode |= fOpen & RTFILE_O_APPEND ? O_APPEND | O_RDWR   : O_RDWR;
+            break;
+        default:
+            AssertMsgFailedReturn(("RTFileOpen received an invalid RW value, fOpen=%#llx\n", fOpen), VERR_INVALID_FLAGS);
+    }
+
+    /* File mode. */
+    int fMode = (fOpen & RTFILE_O_CREATE_MODE_MASK)
+              ? (fOpen & RTFILE_O_CREATE_MODE_MASK) >> RTFILE_O_CREATE_MODE_SHIFT
+              : RT_FILE_PERMISSION;
+
+    /** @todo sharing? */
+
+    /*
+     * Open/create the file.
+     */
+    char const *pszNativeFilename;
+    rc = rtPathToNative(&pszNativeFilename, pszFilename, NULL);
+    if (RT_FAILURE(rc))
+        return (rc);
+
+    int fh;
+    int iErr;
+    if (!penmActionTaken)
+    {
+        fh   = open(pszNativeFilename, fOpenMode, fMode);
+        iErr = errno;
+    }
+    else
+    {
+        /* We need to know exactly which action was taken by open, Windows &
+           OS/2 style.  Can be tedious and subject to races:  */
+        switch (fOpen & RTFILE_O_ACTION_MASK)
+        {
+            case RTFILE_O_OPEN:
+                Assert(!(fOpenMode & O_CREAT));
+                Assert(!(fOpenMode & O_EXCL));
+                fh   = open(pszNativeFilename, fOpenMode, fMode);
+                iErr = errno;
+                if (fh >= 0)
+                    *penmActionTaken = fOpenMode & O_TRUNC ? RTFILEACTION_TRUNCATED : RTFILEACTION_OPENED;
+                break;
+
+            case RTFILE_O_CREATE:
+                Assert(fOpenMode & O_CREAT);
+                Assert(fOpenMode & O_EXCL);
+                fh   = open(pszNativeFilename, fOpenMode, fMode);
+                iErr = errno;
+                if (fh >= 0)
+                    *penmActionTaken = RTFILEACTION_CREATED;
+                else if (iErr == EEXIST)
+                    *penmActionTaken = RTFILEACTION_ALREADY_EXISTS;
+                break;
+
+            case RTFILE_O_OPEN_CREATE:
+            case RTFILE_O_CREATE_REPLACE:
+            {
+                Assert(fOpenMode & O_CREAT);
+                Assert(!(fOpenMode & O_EXCL));
+                int iTries = 64;
+                while (iTries-- > 0)
+                {
+                    /* Yield the CPU if we've raced too long. */
+                    if (iTries < 4)
+                        RTThreadSleep(2 - (iTries & 1));
+
+                    /* Try exclusive creation first: */
+                    fh   = open(pszNativeFilename, fOpenMode | O_EXCL, fMode);
+                    iErr = errno;
+                    if (fh >= 0)
+                    {
+                        *penmActionTaken = RTFILEACTION_CREATED;
+                        break;
+                    }
+                    if (iErr != EEXIST)
+                        break;
+
+                    /* If the file exists, try open it: */
+                    fh   = open(pszNativeFilename, fOpenMode & ~O_CREAT, fMode);
+                    iErr = errno;
+                    if (fh >= 0)
+                    {
+                        if ((fOpen & RTFILE_O_ACTION_MASK) == RTFILE_O_OPEN_CREATE)
+                            *penmActionTaken = fOpenMode & O_TRUNC ? RTFILEACTION_TRUNCATED : RTFILEACTION_OPENED;
+                        else
+                            *penmActionTaken = RTFILEACTION_REPLACED;
+                        break;
+                    }
+                    if (iErr != ENOENT)
+                        break;
+                }
+                Assert(iTries >= 0);
+                if (iTries < 0)
+                {
+                    /* Thanks for the race, but we need to get on with things.  */
+                    fh   = open(pszNativeFilename, fOpenMode, fMode);
+                    iErr = errno;
+                    if (fh >= 0)
+                        *penmActionTaken = RTFILEACTION_OPENED;
+                }
+                break;
+            }
+
+            default:
+                AssertMsgFailed(("fOpen=%#llx fOpenMode=%#x\n", fOpen, fOpenMode));
+                iErr = EINVAL;
+                fh = -1;
+                break;
+        }
+    }
+
+    rtPathFreeNative(pszNativeFilename, pszFilename);
+    if (fh >= 0)
+    {
+        iErr = 0;
+
+        /*
+         * If temporary file, delete it.
+         */
+        if (fOpen & RTFILE_O_TEMP_AUTO_DELETE)
+        {
+            /** @todo Use funlinkat/funlink or similar here when available!  Or better,
+             *        use O_TMPFILE, only that may require fallback as not supported by
+             *        all file system on linux. */
+            iErr = unlink(pszNativeFilename);
+            Assert(iErr == 0);
+        }
+
+        /*
+         * Mark the file handle close on exec, unless inherit is specified.
+         */
+        if (    !(fOpen & RTFILE_O_INHERIT)
+#ifdef O_NOINHERIT
+            &&  !(fOpenMode & O_NOINHERIT)  /* Take care since it might be a zero value dummy. */
+#endif
+#ifdef O_CLOEXEC
+            &&  fHave_O_CLOEXEC <= 0
+#endif
+            )
+            iErr = fcntl(fh, F_SETFD, FD_CLOEXEC) >= 0 ? 0 : errno;
+
+        /*
+         * Switch direct I/O on now if requested and required.
+         */
+#if defined(RT_OS_DARWIN) \
+ || (defined(RT_OS_SOLARIS) && !defined(IN_GUEST))
+        if (iErr == 0 && (fOpen & RTFILE_O_NO_CACHE))
+        {
+# if defined(RT_OS_DARWIN)
+            iErr = fcntl(fh, F_NOCACHE, 1)        >= 0 ? 0 : errno;
+# else
+            iErr = directio(fh, DIRECTIO_ON)      >= 0 ? 0 : errno;
+# endif
+        }
+#endif
+
+        /*
+         * Implement / emulate file sharing.
+         *
+         * We need another mode which allows skipping this stuff completely
+         * and do things the UNIX way. So for the present this is just a debug
+         * aid that can be enabled by developers too lazy to test on Windows.
+         */
+#if 0 && defined(RT_OS_LINUX)
+        if (iErr == 0)
+        {
+            /* This approach doesn't work because only knfsd checks for these
+               buggers. :-( */
+            int iLockOp;
+            switch (fOpen & RTFILE_O_DENY_MASK)
+            {
+                default:
+                AssertFailed();
+                case RTFILE_O_DENY_NONE:
+                case RTFILE_O_DENY_NOT_DELETE:
+                    iLockOp = LOCK_MAND | LOCK_READ | LOCK_WRITE;
+                    break;
+                case RTFILE_O_DENY_READ:
+                case RTFILE_O_DENY_READ | RTFILE_O_DENY_NOT_DELETE:
+                    iLockOp = LOCK_MAND | LOCK_WRITE;
+                    break;
+                case RTFILE_O_DENY_WRITE:
+                case RTFILE_O_DENY_WRITE | RTFILE_O_DENY_NOT_DELETE:
+                    iLockOp = LOCK_MAND | LOCK_READ;
+                    break;
+                case RTFILE_O_DENY_WRITE | RTFILE_O_DENY_READ:
+                case RTFILE_O_DENY_WRITE | RTFILE_O_DENY_READ | RTFILE_O_DENY_NOT_DELETE:
+                    iLockOp = LOCK_MAND;
+                    break;
+            }
+            iErr = flock(fh, iLockOp | LOCK_NB);
+            if (iErr != 0)
+                iErr = errno == EAGAIN ? ETXTBSY : 0;
+        }
+#endif /* 0 && RT_OS_LINUX */
+#if defined(DEBUG_bird) && !defined(RT_OS_SOLARIS)
+        if (iErr == 0)
+        {
+            /* This emulation is incomplete but useful. */
+            switch (fOpen & RTFILE_O_DENY_MASK)
+            {
+                default:
+                AssertFailed();
+                case RTFILE_O_DENY_NONE:
+                case RTFILE_O_DENY_NOT_DELETE:
+                case RTFILE_O_DENY_READ:
+                case RTFILE_O_DENY_READ | RTFILE_O_DENY_NOT_DELETE:
+                    break;
+                case RTFILE_O_DENY_WRITE:
+                case RTFILE_O_DENY_WRITE | RTFILE_O_DENY_NOT_DELETE:
+                case RTFILE_O_DENY_WRITE | RTFILE_O_DENY_READ:
+                case RTFILE_O_DENY_WRITE | RTFILE_O_DENY_READ | RTFILE_O_DENY_NOT_DELETE:
+                    if (fOpen & RTFILE_O_WRITE)
+                    {
+                        iErr = flock(fh, LOCK_EX | LOCK_NB);
+                        if (iErr != 0)
+                            iErr = errno == EAGAIN ? ETXTBSY : 0;
+                    }
+                    break;
+            }
+        }
+#endif
+#ifdef RT_OS_SOLARIS
+        /** @todo Use fshare_t and associates, it's a perfect match. see sys/fcntl.h */
+#endif
+
+        /*
+         * We're done.
+         */
+        if (iErr == 0)
+        {
+            *phFile = (RTFILE)(uintptr_t)fh;
+            Assert((intptr_t)*phFile == fh);
+            LogFlow(("RTFileOpen(%p:{%RTfile}, %p:{%s}, %#llx): returns %Rrc\n",
+                     phFile, *phFile, pszFilename, pszFilename, fOpen, rc));
+            return VINF_SUCCESS;
+        }
+
+        close(fh);
+    }
+    return RTErrConvertFromErrno(iErr);
+}
+
+
+RTR3DECL(int)  RTFileOpenBitBucket(PRTFILE phFile, uint64_t fAccess)
+{
+    AssertReturn(   fAccess == RTFILE_O_READ
+                 || fAccess == RTFILE_O_WRITE
+                 || fAccess == RTFILE_O_READWRITE,
+                 VERR_INVALID_PARAMETER);
+    return RTFileOpen(phFile, "/dev/null", fAccess | RTFILE_O_DENY_NONE | RTFILE_O_OPEN);
+}
+
+
+RTR3DECL(int)  RTFileClose(RTFILE hFile)
+{
+    if (hFile == NIL_RTFILE)
+        return VINF_SUCCESS;
+    if (close(RTFileToNative(hFile)) == 0)
+        return VINF_SUCCESS;
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int) RTFileFromNative(PRTFILE pFile, RTHCINTPTR uNative)
+{
+    AssertCompile(sizeof(uNative) == sizeof(*pFile));
+    if (uNative < 0)
+    {
+        AssertMsgFailed(("%p\n", uNative));
+        *pFile = NIL_RTFILE;
+        return VERR_INVALID_HANDLE;
+    }
+    *pFile = (RTFILE)uNative;
+    return VINF_SUCCESS;
+}
+
+
+RTR3DECL(RTHCINTPTR) RTFileToNative(RTFILE hFile)
+{
+    AssertReturn(hFile != NIL_RTFILE, -1);
+    return (intptr_t)hFile;
+}
+
+
+RTFILE rtFileGetStandard(RTHANDLESTD enmStdHandle)
+{
+    int fd;
+    switch (enmStdHandle)
+    {
+        case RTHANDLESTD_INPUT:  fd = 0; break;
+        case RTHANDLESTD_OUTPUT: fd = 1; break;
+        case RTHANDLESTD_ERROR:  fd = 2; break;
+        default:
+            AssertFailedReturn(NIL_RTFILE);
+    }
+
+    struct stat st;
+    int rc = fstat(fd, &st);
+    if (rc == -1)
+        return NIL_RTFILE;
+    return (RTFILE)(intptr_t)fd;
+}
+
+
+RTR3DECL(int)  RTFileDelete(const char *pszFilename)
+{
+    char const *pszNativeFilename;
+    int rc = rtPathToNative(&pszNativeFilename, pszFilename, NULL);
+    if (RT_SUCCESS(rc))
+    {
+        if (unlink(pszNativeFilename) != 0)
+            rc = RTErrConvertFromErrno(errno);
+        rtPathFreeNative(pszNativeFilename, pszFilename);
+    }
+    return rc;
+}
+
+
+RTR3DECL(int)  RTFileSeek(RTFILE hFile, int64_t offSeek, unsigned uMethod, uint64_t *poffActual)
+{
+    static const unsigned aSeekRecode[] =
+    {
+        SEEK_SET,
+        SEEK_CUR,
+        SEEK_END,
+    };
+
+    /*
+     * Validate input.
+     */
+    if (uMethod > RTFILE_SEEK_END)
+    {
+        AssertMsgFailed(("Invalid uMethod=%d\n", uMethod));
+        return VERR_INVALID_PARAMETER;
+    }
+
+    /* check that within off_t range. */
+    if (    sizeof(off_t) < sizeof(offSeek)
+        && (    (offSeek > 0 && (unsigned)(offSeek >> 32) != 0)
+            ||  (offSeek < 0 && (unsigned)(-offSeek >> 32) != 0)))
+    {
+        AssertMsgFailed(("64-bit search not supported\n"));
+        return VERR_NOT_SUPPORTED;
+    }
+
+    off_t offCurrent = lseek(RTFileToNative(hFile), (off_t)offSeek, aSeekRecode[uMethod]);
+    if (offCurrent != ~0)
+    {
+        if (poffActual)
+            *poffActual = (uint64_t)offCurrent;
+        return VINF_SUCCESS;
+    }
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int)  RTFileRead(RTFILE hFile, void *pvBuf, size_t cbToRead, size_t *pcbRead)
+{
+    if (cbToRead <= 0)
+    {
+        if (pcbRead)
+            *pcbRead = 0;
+        return VINF_SUCCESS;
+    }
+
+    /*
+     * Attempt read.
+     */
+    ssize_t cbRead = read(RTFileToNative(hFile), pvBuf, cbToRead);
+    if (cbRead >= 0)
+    {
+        if (pcbRead)
+            /* caller can handle partial read. */
+            *pcbRead = cbRead;
+        else
+        {
+            /* Caller expects all to be read. */
+            while ((ssize_t)cbToRead > cbRead)
+            {
+                ssize_t cbReadPart = read(RTFileToNative(hFile), (char*)pvBuf + cbRead, cbToRead - cbRead);
+                if (cbReadPart <= 0)
+                {
+                    if (cbReadPart == 0)
+                        return VERR_EOF;
+                    return RTErrConvertFromErrno(errno);
+                }
+                cbRead += cbReadPart;
+            }
+        }
+        return VINF_SUCCESS;
+    }
+
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int)  RTFileWrite(RTFILE hFile, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten)
+{
+    if (cbToWrite <= 0)
+        return VINF_SUCCESS;
+
+    /*
+     * Attempt write.
+     */
+    ssize_t cbWritten = write(RTFileToNative(hFile), pvBuf, cbToWrite);
+    if (cbWritten >= 0)
+    {
+        if (pcbWritten)
+            /* caller can handle partial write. */
+            *pcbWritten = cbWritten;
+        else
+        {
+            /* Caller expects all to be write. */
+            while ((ssize_t)cbToWrite > cbWritten)
+            {
+                ssize_t cbWrittenPart = write(RTFileToNative(hFile), (const char *)pvBuf + cbWritten, cbToWrite - cbWritten);
+                if (cbWrittenPart <= 0)
+                    return cbWrittenPart < 0 ? RTErrConvertFromErrno(errno) : VERR_TRY_AGAIN;
+                cbWritten += cbWrittenPart;
+            }
+        }
+        return VINF_SUCCESS;
+    }
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int)  RTFileSetSize(RTFILE hFile, uint64_t cbSize)
+{
+    /*
+     * Validate offset.
+     */
+    if (    sizeof(off_t) < sizeof(cbSize)
+        &&  (cbSize >> 32) != 0)
+    {
+        AssertMsgFailed(("64-bit filesize not supported! cbSize=%lld\n", cbSize));
+        return VERR_NOT_SUPPORTED;
+    }
+
+#if defined(_MSC_VER) || (defined(RT_OS_OS2) && (!defined(__INNOTEK_LIBC__) || __INNOTEK_LIBC__ < 0x006))
+    if (chsize(RTFileToNative(hFile), (off_t)cbSize) == 0)
+#else
+    /* This relies on a non-standard feature of FreeBSD, Linux, and OS/2
+     * LIBC v0.6 and higher. (SuS doesn't define ftruncate() and size bigger
+     * than the file.)
+     */
+    if (ftruncate(RTFileToNative(hFile), (off_t)cbSize) == 0)
+#endif
+        return VINF_SUCCESS;
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int) RTFileQuerySize(RTFILE hFile, uint64_t *pcbSize)
+{
+    /*
+     * Ask fstat() first.
+     */
+    struct stat st;
+    if (!fstat(RTFileToNative(hFile), &st))
+    {
+        *pcbSize = st.st_size;
+        if (   st.st_size != 0
+#if defined(RT_OS_SOLARIS) || defined(RT_OS_DARWIN)
+            || (!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode))
+#elif defined(RT_OS_FREEBSD) || defined(RT_OS_NETBSD) || defined(RT_OS_DARWIN)
+            || !S_ISCHR(st.st_mode)
+#else
+            || !S_ISBLK(st.st_mode)
+#endif
+            )
+            return VINF_SUCCESS;
+
+        /*
+         * It could be a block device.  Try determin the size by I/O control
+         * query or seek.
+         */
+#ifdef RT_OS_DARWIN
+        uint64_t cBlocks;
+        if (!ioctl(RTFileToNative(hFile), DKIOCGETBLOCKCOUNT, &cBlocks))
+        {
+            uint32_t cbBlock;
+            if (!ioctl(RTFileToNative(hFile), DKIOCGETBLOCKSIZE, &cbBlock))
+            {
+                *pcbSize = cBlocks * cbBlock;
+                return VINF_SUCCESS;
+            }
+        }
+
+        /* Always fail block devices.  Character devices doesn't all need to be
+           /dev/rdisk* nodes, they should return ENOTTY but /dev/null returns ENODEV
+           and we include EINVAL just in case. */
+        if (!S_ISBLK(st.st_mode) && (errno == ENOTTY || errno == ENODEV || errno == EINVAL))
+            return VINF_SUCCESS;
+
+#elif defined(RT_OS_SOLARIS)
+        struct dk_minfo MediaInfo;
+        if (!ioctl(RTFileToNative(hFile), DKIOCGMEDIAINFO, &MediaInfo))
+        {
+            *pcbSize = MediaInfo.dki_capacity * MediaInfo.dki_lbsize;
+            return VINF_SUCCESS;
+        }
+        /* might not be a block device. */
+        if (errno == EINVAL || errno == ENOTTY)
+            return VINF_SUCCESS;
+
+#elif defined(RT_OS_FREEBSD)
+        off_t cbMedia = 0;
+        if (!ioctl(RTFileToNative(hFile), DIOCGMEDIASIZE, &cbMedia))
+        {
+            *pcbSize = cbMedia;
+            return VINF_SUCCESS;
+        }
+        /* might not be a block device. */
+        if (errno == EINVAL || errno == ENOTTY)
+            return VINF_SUCCESS;
+
+#else
+        /* PORTME! Avoid this path when possible. */
+        uint64_t offSaved = UINT64_MAX;
+        int rc = RTFileSeek(hFile, 0, RTFILE_SEEK_CURRENT, &offSaved);
+        if (RT_SUCCESS(rc))
+        {
+            rc = RTFileSeek(hFile, 0, RTFILE_SEEK_END, pcbSize);
+            int rc2 = RTFileSeek(hFile, offSaved, RTFILE_SEEK_BEGIN, NULL);
+            if (RT_SUCCESS(rc))
+                return rc2;
+        }
+#endif
+    }
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int) RTFileQueryMaxSizeEx(RTFILE hFile, PRTFOFF pcbMax)
+{
+    /*
+     * Save the current location
+     */
+    uint64_t offOld = UINT64_MAX;
+    int rc = RTFileSeek(hFile, 0, RTFILE_SEEK_CURRENT, &offOld);
+    if (RT_FAILURE(rc))
+        return rc;
+
+    uint64_t offLow  =       0;
+    uint64_t offHigh = INT64_MAX; /* we don't need bigger files */
+    /** @todo Unfortunately this does not work for certain file system types,
+     * for instance cifs mounts. Even worse, statvfs.f_fsid returns 0 for such
+     * file systems. */
+
+    /*
+     * Quickly guess the order of magnitude for offHigh and offLow.
+     */
+    {
+        uint64_t offHighPrev = offHigh;
+        while (offHigh >= INT32_MAX)
+        {
+            rc = RTFileSeek(hFile, offHigh, RTFILE_SEEK_BEGIN, NULL);
+            if (RT_SUCCESS(rc))
+            {
+                offLow = offHigh;
+                offHigh = offHighPrev;
+                break;
+            }
+            else
+            {
+                offHighPrev = offHigh;
+                offHigh >>= 8;
+            }
+        }
+    }
+
+    /*
+     * Sanity: if the seek to the initial offHigh (INT64_MAX) works, then
+     * this algorithm cannot possibly work. Declare defeat.
+     */
+    if (offLow == offHigh)
+    {
+        rc = RTFileSeek(hFile, offOld, RTFILE_SEEK_BEGIN, NULL);
+        if (RT_SUCCESS(rc))
+            rc = VERR_NOT_IMPLEMENTED;
+
+        return rc;
+    }
+
+    /*
+     * Perform a binary search for the max file size.
+     */
+    while (offLow <= offHigh)
+    {
+        uint64_t offMid = offLow + (offHigh - offLow) / 2;
+        rc = RTFileSeek(hFile, offMid, RTFILE_SEEK_BEGIN, NULL);
+        if (RT_FAILURE(rc))
+            offHigh = offMid - 1;
+        else
+            offLow  = offMid + 1;
+    }
+
+    if (pcbMax)
+        *pcbMax = RT_MIN(offLow, offHigh);
+    return RTFileSeek(hFile, offOld, RTFILE_SEEK_BEGIN, NULL);
+}
+
+
+RTR3DECL(bool) RTFileIsValid(RTFILE hFile)
+{
+    if (hFile != NIL_RTFILE)
+    {
+        int fFlags = fcntl(RTFileToNative(hFile), F_GETFD);
+        if (fFlags >= 0)
+            return true;
+    }
+    return false;
+}
+
+
+RTR3DECL(int) RTFileFlush(RTFILE hFile)
+{
+    if (!fsync(RTFileToNative(hFile)))
+        return VINF_SUCCESS;
+    /* Ignore EINVAL here as that's what returned for pseudo ttys
+       and other odd handles. */
+    if (errno == EINVAL)
+        return VINF_NOT_SUPPORTED;
+    return RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int) RTFileIoCtl(RTFILE hFile, unsigned long ulRequest, void *pvData, unsigned cbData, int *piRet)
+{
+    NOREF(cbData);
+    int rc = ioctl(RTFileToNative(hFile), ulRequest, pvData);
+    if (piRet)
+        *piRet = rc;
+    return rc >= 0 ? VINF_SUCCESS : RTErrConvertFromErrno(errno);
+}
+
+
+RTR3DECL(int) RTFileSetMode(RTFILE hFile, RTFMODE fMode)
+{
+    /*
+     * Normalize the mode and call the API.
+     */
+    fMode = rtFsModeNormalize(fMode, NULL, 0, RTFS_TYPE_FILE);
+    if (!rtFsModeIsValid(fMode))
+        return VERR_INVALID_PARAMETER;
+
+    if (fchmod(RTFileToNative(hFile), fMode & RTFS_UNIX_MASK))
+    {
+        int rc = RTErrConvertFromErrno(errno);
+        Log(("RTFileSetMode(%RTfile,%RTfmode): returns %Rrc\n", hFile, fMode, rc));
+        return rc;
+    }
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTFileSetOwner(RTFILE hFile, uint32_t uid, uint32_t gid)
+{
+    uid_t uidNative = uid != NIL_RTUID ? (uid_t)uid : (uid_t)-1;
+    AssertReturn(uid == uidNative, VERR_INVALID_PARAMETER);
+    gid_t gidNative = gid != NIL_RTGID ? (gid_t)gid : (gid_t)-1;
+    AssertReturn(gid == gidNative, VERR_INVALID_PARAMETER);
+
+    if (fchown(RTFileToNative(hFile), uidNative, gidNative))
+        return RTErrConvertFromErrno(errno);
+    return VINF_SUCCESS;
+}
+
+
+RTR3DECL(int) RTFileRename(const char *pszSrc, const char *pszDst, unsigned fRename)
+{
+    /*
+     * Validate input.
+     */
+    AssertPtrReturn(pszSrc, VERR_INVALID_POINTER);
+    AssertPtrReturn(pszDst, VERR_INVALID_POINTER);
+    AssertMsgReturn(*pszSrc, ("%p\n", pszSrc), VERR_INVALID_PARAMETER);
+    AssertMsgReturn(*pszDst, ("%p\n", pszDst), VERR_INVALID_PARAMETER);
+    AssertMsgReturn(!(fRename & ~RTPATHRENAME_FLAGS_REPLACE), ("%#x\n", fRename), VERR_INVALID_PARAMETER);
+
+    /*
+     * Take common cause with RTPathRename.
+     */
+    int rc = rtPathPosixRename(pszSrc, pszDst, fRename, RTFS_TYPE_FILE);
+
+    LogFlow(("RTDirRename(%p:{%s}, %p:{%s}, %#x): returns %Rrc\n",
+             pszSrc, pszSrc, pszDst, pszDst, fRename, rc));
+    return rc;
+}
+