/* $Id: fileio-posix.cpp 62477 2016-07-22 18:27:37Z vboxsync $ */ /** @file * IPRT - File I/O, POSIX, Part 1. */ /* * Copyright (C) 2006-2016 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 * *********************************************************************************************************************************/ #define LOG_GROUP RTLOGGROUP_FILE #include #include #include #include #include #ifdef _MSC_VER # include # include #else # include # include #endif #ifdef RT_OS_LINUX # include #endif #if defined(RT_OS_OS2) && (!defined(__INNOTEK_LIBC__) || __INNOTEK_LIBC__ < 0x006) # include #endif #if defined(RT_OS_DARWIN) || defined(RT_OS_FREEBSD) # include #endif #ifdef RT_OS_SOLARIS # include # include # include #endif /* RT_OS_SOLARIS */ #include #include #include #include #include #include #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 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; } RTR3DECL(int) RTFileOpen(PRTFILE pFile, const char *pszFilename, uint64_t fOpen) { /* * Validate input. */ AssertPtrReturn(pFile, VERR_INVALID_POINTER); *pFile = NIL_RTFILE; 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 if (fOpen & RTFILE_O_NON_BLOCK) { AssertMsgFailed(("Invalid parameters! fOpen=%#llx\n", fOpen)); return VERR_INVALID_PARAMETER; } #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 static int s_fHave_O_CLOEXEC = 0; /* {-1,0,1}; since Linux 2.6.23 */ if (!(fOpen & RTFILE_O_INHERIT) && s_fHave_O_CLOEXEC >= 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)) /* 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! */ } if (fOpen & RTFILE_O_TRUNCATE) 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: AssertMsgFailed(("RTFileOpen received an invalid RW value, fOpen=%#llx\n", fOpen)); return VERR_INVALID_PARAMETER; } /* 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 = open(pszNativeFilename, fOpenMode, fMode); int iErr = errno; #ifdef O_CLOEXEC if ( (fOpenMode & O_CLOEXEC) && s_fHave_O_CLOEXEC == 0) { if (fh < 0 && iErr == EINVAL) { s_fHave_O_CLOEXEC = -1; fh = open(pszNativeFilename, fOpenMode, fMode); iErr = errno; } else if (fh >= 0) s_fHave_O_CLOEXEC = fcntl(fh, F_GETFD, 0) > 0 ? 1 : -1; } #endif rtPathFreeNative(pszNativeFilename, pszFilename); if (fh >= 0) { 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 && s_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) { *pFile = (RTFILE)(uintptr_t)fh; Assert((intptr_t)*pFile == fh); LogFlow(("RTFileOpen(%p:{%RTfile}, %p:{%s}, %#llx): returns %Rrc\n", pFile, *pFile, 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) 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 RTErrConvertFromErrno(errno); 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) RTFileGetSize(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) || (!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) #elif defined(RT_OS_FREEBSD) || !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; } } /* must be a block device, fail on failure. */ #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; 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) RTFileGetMaxSizeEx(RTFILE hFile, PRTFOFF pcbMax) { /* * Save the current location */ uint64_t offOld; int rc = RTFileSeek(hFile, 0, RTFILE_SEEK_CURRENT, &offOld); if (RT_FAILURE(rc)) return rc; /* * Perform a binary search for the max file size. */ uint64_t offLow = 0; uint64_t offHigh = 8 * _1T; /* 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. */ //uint64_t offHigh = INT64_MAX; for (;;) { uint64_t cbInterval = (offHigh - offLow) >> 1; if (cbInterval == 0) { if (pcbMax) *pcbMax = offLow; return RTFileSeek(hFile, offOld, RTFILE_SEEK_BEGIN, NULL); } rc = RTFileSeek(hFile, offLow + cbInterval, RTFILE_SEEK_BEGIN, NULL); if (RT_FAILURE(rc)) offHigh = offLow + cbInterval; else offLow = offLow + cbInterval; } } 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 RTErrConvertFromErrno(errno); return VINF_SUCCESS; } 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); 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. */ AssertMsgReturn(VALID_PTR(pszSrc), ("%p\n", pszSrc), VERR_INVALID_POINTER); AssertMsgReturn(VALID_PTR(pszDst), ("%p\n", 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; }