/** @file * IPRT - Virtual Filesystem. */ /* * Copyright (C) 2010-2022 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 . * * 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 */ #ifndef IPRT_INCLUDED_vfslowlevel_h #define IPRT_INCLUDED_vfslowlevel_h #ifndef RT_WITHOUT_PRAGMA_ONCE # pragma once #endif #include #include #include #include RT_C_DECLS_BEGIN /** @defgroup grp_rt_vfs_lowlevel RTVfs - Low-level Interface. * @ingroup grp_rt_vfs * @{ */ /** @name VFS Lock Abstraction * @todo This should be moved somewhere else as it is of general use. * @{ */ /** * VFS lock types. */ typedef enum RTVFSLOCKTYPE { /** Invalid lock type. */ RTVFSLOCKTYPE_INVALID = 0, /** Read write semaphore. */ RTVFSLOCKTYPE_RW, /** Fast mutex semaphore (critical section in ring-3). */ RTVFSLOCKTYPE_FASTMUTEX, /** Full fledged mutex semaphore. */ RTVFSLOCKTYPE_MUTEX, /** The end of valid lock types. */ RTVFSLOCKTYPE_END, /** The customary 32-bit type hack. */ RTVFSLOCKTYPE_32BIT_HACK = 0x7fffffff } RTVFSLOCKTYPE; /** VFS lock handle. */ typedef struct RTVFSLOCKINTERNAL *RTVFSLOCK; /** Pointer to a VFS lock handle. */ typedef RTVFSLOCK *PRTVFSLOCK; /** Nil VFS lock handle. */ #define NIL_RTVFSLOCK ((RTVFSLOCK)~(uintptr_t)0) /** Special handle value for creating a new read/write semaphore based lock. */ #define RTVFSLOCK_CREATE_RW ((RTVFSLOCK)~(uintptr_t)1) /** Special handle value for creating a new fast mutex semaphore based lock. */ #define RTVFSLOCK_CREATE_FASTMUTEX ((RTVFSLOCK)~(uintptr_t)2) /** Special handle value for creating a new mutex semaphore based lock. */ #define RTVFSLOCK_CREATE_MUTEX ((RTVFSLOCK)~(uintptr_t)3) /** * Retains a reference to the VFS lock handle. * * @returns New reference count on success, UINT32_MAX on failure. * @param hLock The VFS lock handle. */ RTDECL(uint32_t) RTVfsLockRetain(RTVFSLOCK hLock); /** * Releases a reference to the VFS lock handle. * * @returns New reference count on success (0 if closed), UINT32_MAX on failure. * @param hLock The VFS lock handle. */ RTDECL(uint32_t) RTVfsLockRelease(RTVFSLOCK hLock); /** * Gets the lock type. * * @returns The lock type on success, RTVFSLOCKTYPE_INVALID if the handle is * not valid. * @param hLock The lock handle. */ RTDECL(RTVFSLOCKTYPE) RTVfsLockGetType(RTVFSLOCK hLock); RTDECL(void) RTVfsLockAcquireReadSlow(RTVFSLOCK hLock); RTDECL(void) RTVfsLockReleaseReadSlow(RTVFSLOCK hLock); RTDECL(void) RTVfsLockAcquireWriteSlow(RTVFSLOCK hLock); RTDECL(void) RTVfsLockReleaseWriteSlow(RTVFSLOCK hLock); /** * Acquire a read lock. * * @param hLock The lock handle, can be NIL. */ DECLINLINE(void) RTVfsLockAcquireRead(RTVFSLOCK hLock) { if (hLock != NIL_RTVFSLOCK) RTVfsLockAcquireReadSlow(hLock); } /** * Release a read lock. * * @param hLock The lock handle, can be NIL. */ DECLINLINE(void) RTVfsLockReleaseRead(RTVFSLOCK hLock) { if (hLock != NIL_RTVFSLOCK) RTVfsLockReleaseReadSlow(hLock); } /** * Acquire a write lock. * * @param hLock The lock handle, can be NIL. */ DECLINLINE(void) RTVfsLockAcquireWrite(RTVFSLOCK hLock) { if (hLock != NIL_RTVFSLOCK) RTVfsLockAcquireWriteSlow(hLock); } /** * Release a write lock. * * @param hLock The lock handle, can be NIL. */ DECLINLINE(void) RTVfsLockReleaseWrite(RTVFSLOCK hLock) { if (hLock != NIL_RTVFSLOCK) RTVfsLockReleaseWriteSlow(hLock); } /** @} */ /** * Info queried via RTVFSOBJOPS::pfnQueryInfoEx, ++. */ typedef enum RTVFSQIEX { /** Invalid zero value. */ RTVFSQIEX_INVALID = 0, /** Volume label. * Returns a UTF-8 string. */ RTVFSQIEX_VOL_LABEL, /** Alternative volume label, the primary one for ISOs, otherwise treated same * as RTVFSQIEX_VOL_LABEL. */ RTVFSQIEX_VOL_LABEL_ALT, /** Volume serial number. * Returns a uint32_t, uint64_t or RTUUID. */ RTVFSQIEX_VOL_SERIAL, /** End of valid queries. */ RTVFSQIEX_END, /** The usual 32-bit hack. */ RTVFSQIEX_32BIT_SIZE_HACK = 0x7fffffff } RTVFSQIEX; /** * The basis for all virtual file system objects. */ typedef struct RTVFSOBJOPS { /** The structure version (RTVFSOBJOPS_VERSION). */ uint32_t uVersion; /** The object type for type introspection. */ RTVFSOBJTYPE enmType; /** The name of the operations. */ const char *pszName; /** * Close the object. * * @returns IPRT status code. * @param pvThis The implementation specific file data. */ DECLCALLBACKMEMBER(int, pfnClose,(void *pvThis)); /** * Get information about the file. * * @returns IPRT status code. See RTVfsObjQueryInfo. * @retval VERR_WRONG_TYPE if file system or file system stream. * * @param pvThis The implementation specific file data. * @param pObjInfo Where to return the object info on success. * @param enmAddAttr Which set of additional attributes to request. * @sa RTVfsObjQueryInfo, RTFileQueryInfo, RTPathQueryInfo */ DECLCALLBACKMEMBER(int, pfnQueryInfo,(void *pvThis, PRTFSOBJINFO pObjInfo, RTFSOBJATTRADD enmAddAttr)); /** * Query arbritray information about the file, volume, or whatever. * * @returns IPRT status code. * @retval VERR_BUFFER_OVERFLOW sets pcbRet. * * @param pvThis The implementation specific file data. * @param enmInfo The information being queried. * @param pvInfo Where to return the info. * @param cbInfo The size of the @a pvInfo buffer. * @param pcbRet The size of the returned data. In case of * VERR_BUFFER_OVERFLOW this will be set to the required * buffer size. */ DECLCALLBACKMEMBER(int, pfnQueryInfoEx,(void *pvThis, RTVFSQIEX enmInfo, void *pvInfo, size_t cbInfo, size_t *pcbRet)); /** Marks the end of the structure (RTVFSOBJOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSOBJOPS; /** Pointer to constant VFS object operations. */ typedef RTVFSOBJOPS const *PCRTVFSOBJOPS; /** The RTVFSOBJOPS structure version. */ #define RTVFSOBJOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x1f,2,0) /** * The VFS operations. */ typedef struct RTVFSOPS { /** The basic object operation. */ RTVFSOBJOPS Obj; /** The structure version (RTVFSOPS_VERSION). */ uint32_t uVersion; /** The virtual file system feature mask. */ uint32_t fFeatures; /** * Opens the root directory. * * @returns IPRT status code. * @param pvThis The implementation specific data. * @param phVfsDir Where to return the handle to the root directory. */ DECLCALLBACKMEMBER(int, pfnOpenRoot,(void *pvThis, PRTVFSDIR phVfsDir)); /** * Query the status of the given storage range (optional). * * This can be used by the image compaction utilites to evict non-zero blocks * that aren't currently being used by the file system. * * @returns IPRT status code. * @param pvThis The implementation specific data. * @param off Start offset to check. * @param cb Number of bytes to check. * @param pfUsed Where to store whether the given range is in use. */ DECLCALLBACKMEMBER(int, pfnQueryRangeState,(void *pvThis, uint64_t off, size_t cb, bool *pfUsed)); /** @todo There will be more methods here to optimize opening and * querying. */ #if 0 /** * Optional entry point for optimizing path traversal within the file system. * * @returns IPRT status code. * @param pvThis The implementation specific data. * @param pszPath The path to resolve. * @param poffPath The current path offset on input, what we've * traversed to on successful return. * @param phVfs??? Return handle to what we've traversed. * @param p??? Return other stuff... */ DECLCALLBACKMEMBER(int, pfnTraverse,(void *pvThis, const char *pszPath, size_t *poffPath, PRTVFS??? phVfs?, ???* p???)); #endif /** @todo need rename API */ /** Marks the end of the structure (RTVFSOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSOPS; /** Pointer to constant VFS operations. */ typedef RTVFSOPS const *PCRTVFSOPS; /** The RTVFSOPS structure version. */ #define RTVFSOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x0f,1,0) /** @name RTVFSOPS::fFeatures * @{ */ /** The VFS supports attaching other systems. */ #define RTVFSOPS_FEAT_ATTACH RT_BIT_32(0) /** @} */ /** * Creates a new VFS handle. * * @returns IPRT status code * @param pVfsOps The VFS operations. * @param cbInstance The size of the instance data. * @param hVfs The VFS handle to associate this VFS with. * NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param phVfs Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNew(PCRTVFSOPS pVfsOps, size_t cbInstance, RTVFS hVfs, RTVFSLOCK hLock, PRTVFS phVfs, void **ppvInstance); /** * Creates a new VFS base object handle. * * @returns IPRT status code * @param pObjOps The base object operations. * @param cbInstance The size of the instance data. * @param hVfs The VFS handle to associate this base object * with. NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param phVfsObj Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNewBaseObj(PCRTVFSOBJOPS pObjOps, size_t cbInstance, RTVFS hVfs, RTVFSLOCK hLock, PRTVFSOBJ phVfsObj, void **ppvInstance); /** * Gets the private data of a base object. * * @returns Pointer to the private data. NULL if the handle is invalid in some * way. * @param hVfsObj The I/O base object handle. * @param pObjOps The base object operations. This servers as a * sort of password. */ RTDECL(void *) RTVfsObjToPrivate(RTVFSOBJ hVfsObj, PCRTVFSOBJOPS pObjOps); /** * Additional operations for setting object attributes. */ typedef struct RTVFSOBJSETOPS { /** The structure version (RTVFSOBJSETOPS_VERSION). */ uint32_t uVersion; /** The offset back to the RTVFSOBJOPS structure. */ uint32_t offObjOps; /** * Set the unix style owner and group. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param fMode The new mode bits. * @param fMask The mask indicating which bits we are * changing. * @note Optional, failing with VERR_WRITE_PROTECT if NULL. * @sa RTFileSetMode */ DECLCALLBACKMEMBER(int, pfnSetMode,(void *pvThis, RTFMODE fMode, RTFMODE fMask)); /** * Set the timestamps associated with the object. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param pAccessTime Pointer to the new access time. NULL if not * to be changed. * @param pModificationTime Pointer to the new modifcation time. NULL if * not to be changed. * @param pChangeTime Pointer to the new change time. NULL if not * to be changed. * @param pBirthTime Pointer to the new time of birth. NULL if * not to be changed. * @remarks See RTFileSetTimes for restrictions and behavior imposed by the * host OS or underlying VFS provider. * @note Optional, failing with VERR_WRITE_PROTECT if NULL. * @sa RTFileSetTimes */ DECLCALLBACKMEMBER(int, pfnSetTimes,(void *pvThis, PCRTTIMESPEC pAccessTime, PCRTTIMESPEC pModificationTime, PCRTTIMESPEC pChangeTime, PCRTTIMESPEC pBirthTime)); /** * Set the unix style owner and group. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param uid The user ID of the new owner. NIL_RTUID if * unchanged. * @param gid The group ID of the new owner group. NIL_RTGID if * unchanged. * @note Optional, failing with VERR_WRITE_PROTECT if NULL. * @sa RTFileSetOwner */ DECLCALLBACKMEMBER(int, pfnSetOwner,(void *pvThis, RTUID uid, RTGID gid)); /** Marks the end of the structure (RTVFSOBJSETOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSOBJSETOPS; /** Pointer to const object attribute setter operations. */ typedef RTVFSOBJSETOPS const *PCRTVFSOBJSETOPS; /** The RTVFSOBJSETOPS structure version. */ #define RTVFSOBJSETOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x2f,1,0) /** * The filesystem stream operations. * * @extends RTVFSOBJOPS */ typedef struct RTVFSFSSTREAMOPS { /** The basic object operation. */ RTVFSOBJOPS Obj; /** The structure version (RTVFSFSSTREAMOPS_VERSION). */ uint32_t uVersion; /** Reserved field, MBZ. */ uint32_t fReserved; /** * Gets the next object in the stream. * * Readable streams only. * * @returns IPRT status code. * @retval VINF_SUCCESS if a new object was retrieved. * @retval VERR_EOF when there are no more objects. * @param pvThis The implementation specific directory data. * @param ppszName Where to return the object name. Must be freed by * calling RTStrFree. * @param penmType Where to return the object type. * @param phVfsObj Where to return the object handle (referenced). This * must be cast to the desired type before use. * @sa RTVfsFsStrmNext * * @note Setting this member to NULL is okay for write-only streams. */ DECLCALLBACKMEMBER(int, pfnNext,(void *pvThis, char **ppszName, RTVFSOBJTYPE *penmType, PRTVFSOBJ phVfsObj)); /** * Adds another object into the stream. * * Writable streams only. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszPath The path to the object. * @param hVfsObj The object to add. * @param fFlags Reserved for the future, MBZ. * @sa RTVfsFsStrmAdd * * @note Setting this member to NULL is okay for read-only streams. */ DECLCALLBACKMEMBER(int, pfnAdd,(void *pvThis, const char *pszPath, RTVFSOBJ hVfsObj, uint32_t fFlags)); /** * Pushes an byte stream onto the stream (optional). * * Writable streams only. * * This differs from RTVFSFSSTREAMOPS::pfnAdd() in that it will create a regular * file in the output file system stream and provide the actual content bytes * via the returned I/O stream object. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszPath The path to the file. * @param cbFile The file size. This can also be set to UINT64_MAX if * the file system stream is backed by a file. * @param paObjInfo Array of zero or more RTFSOBJINFO structures containing * different pieces of information about the file. If any * provided, the first one should be a RTFSOBJATTRADD_UNIX * one, additional can be supplied if wanted. What exactly * is needed depends on the underlying FS stream * implementation. * @param cObjInfo Number of items in the array @a paObjInfo points at. * @param fFlags RTVFSFSSTRM_PUSH_F_XXX. * @param phVfsIos Where to return the I/O stream to feed the file content * to. If the FS stream is backed by a file, the returned * handle can be cast to a file if necessary. */ DECLCALLBACKMEMBER(int, pfnPushFile,(void *pvThis, const char *pszPath, uint64_t cbFile, PCRTFSOBJINFO paObjInfo, uint32_t cObjInfo, uint32_t fFlags, PRTVFSIOSTREAM phVfsIos)); /** * Marks the end of the stream. * * Writable streams only. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @sa RTVfsFsStrmEnd * * @note Setting this member to NULL is okay for read-only streams. */ DECLCALLBACKMEMBER(int, pfnEnd,(void *pvThis)); /** Marks the end of the structure (RTVFSFSSTREAMOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSFSSTREAMOPS; /** Pointer to const object attribute setter operations. */ typedef RTVFSFSSTREAMOPS const *PCRTVFSFSSTREAMOPS; /** The RTVFSFSSTREAMOPS structure version. */ #define RTVFSFSSTREAMOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x3f,2,0) /** * Creates a new VFS filesystem stream handle. * * @returns IPRT status code * @param pFsStreamOps The filesystem stream operations. * @param cbInstance The size of the instance data. * @param hVfs The VFS handle to associate this filesystem * stream with. NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param fAccess RTFILE_O_READ and/or RTFILE_O_WRITE. * @param phVfsFss Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNewFsStream(PCRTVFSFSSTREAMOPS pFsStreamOps, size_t cbInstance, RTVFS hVfs, RTVFSLOCK hLock, uint32_t fAccess, PRTVFSFSSTREAM phVfsFss, void **ppvInstance); /** * Gets the private data of an filesystem stream. * * @returns Pointer to the private data. NULL if the handle is invalid in some * way. * @param hVfsFss The FS stream handle. * @param pFsStreamOps The FS stream operations. This servers as a * sort of password. */ RTDECL(void *) RTVfsFsStreamToPrivate(RTVFSFSSTREAM hVfsFss, PCRTVFSFSSTREAMOPS pFsStreamOps); /** * The directory operations. * * @extends RTVFSOBJOPS * @extends RTVFSOBJSETOPS */ typedef struct RTVFSDIROPS { /** The basic object operation. */ RTVFSOBJOPS Obj; /** The structure version (RTVFSDIROPS_VERSION). */ uint32_t uVersion; /** Reserved field, MBZ. */ uint32_t fReserved; /** The object setter operations. */ RTVFSOBJSETOPS ObjSet; /** * Generic method for opening any kind of file system object. * * Can also create files and directories. Symbolic links, devices and such * needs to be created using special methods or this would end up being way more * complicated than it already is. * * There are optional specializations available. * * @returns IPRT status code. * @retval VERR_PATH_NOT_FOUND or VERR_FILE_NOT_FOUND if @a pszEntry was not * found. * @retval VERR_IS_A_FILE if @a pszEntry is a file or similar but @a fFlags * indicates that the type of object should not be opened. * @retval VERR_IS_A_DIRECTORY if @a pszEntry is a directory but @a fFlags * indicates that directories should not be opened. * @retval VERR_IS_A_SYMLINK if @a pszEntry is a symbolic link but @a fFlags * indicates that symbolic links should not be opened (or followed). * @retval VERR_IS_A_FIFO if @a pszEntry is a FIFO but @a fFlags indicates that * FIFOs should not be opened. * @retval VERR_IS_A_SOCKET if @a pszEntry is a socket but @a fFlags indicates * that sockets should not be opened. * @retval VERR_IS_A_BLOCK_DEVICE if @a pszEntry is a block device but * @a fFlags indicates that block devices should not be opened, or vice * versa. * * @param pvThis The implementation specific directory data. * @param pszEntry The name of the immediate file to open or create. * @param fOpenFile RTFILE_O_XXX combination. * @param fObjFlags More flags: RTVFSOBJ_F_XXX, RTPATH_F_XXX. * The meaning of RTPATH_F_FOLLOW_LINK differs here, if * @a pszEntry is a symlink it should be opened for * traversal rather than according to @a fOpenFile. * @param phVfsObj Where to return the handle to the opened object. * @sa RTFileOpen, RTDirOpen */ DECLCALLBACKMEMBER(int, pfnOpen,(void *pvThis, const char *pszEntry, uint64_t fOpenFile, uint32_t fObjFlags, PRTVFSOBJ phVfsObj)); /** * Optional method for symbolic link handling in the vfsstddir.cpp. * * This is really just a hack to make symbolic link handling work when working * with directory objects that doesn't have an associated VFS. It also helps * deal with drive letters in symbolic links on Windows and OS/2. * * @returns IPRT status code. * @retval VERR_PATH_IS_RELATIVE if @a pszPath isn't absolute and should be * handled using pfnOpen(). * * @param pvThis The implementation specific directory data. * @param pszRoot Path to the alleged root. * @param phVfsDir Where to return the handle to the specified root * directory (or may current dir on a drive letter). */ DECLCALLBACKMEMBER(int, pfnFollowAbsoluteSymlink,(void *pvThis, const char *pszRoot, PRTVFSDIR phVfsDir)); /** * Open or create a file. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszFilename The name of the immediate file to open or create. * @param fOpen The open flags (RTFILE_O_XXX). * @param phVfsFile Where to return the handle to the opened file. * @note Optional. RTVFSDIROPS::pfnOpenObj will be used if NULL. * @sa RTFileOpen. */ DECLCALLBACKMEMBER(int, pfnOpenFile,(void *pvThis, const char *pszFilename, uint64_t fOpen, PRTVFSFILE phVfsFile)); /** * Open an existing subdirectory. * * @returns IPRT status code. * @retval VERR_IS_A_SYMLINK if @a pszSubDir is a symbolic link. * @retval VERR_NOT_A_DIRECTORY is okay for symbolic links too. * * @param pvThis The implementation specific directory data. * @param pszSubDir The name of the immediate subdirectory to open. * @param fFlags RTDIR_F_XXX. * @param phVfsDir Where to return the handle to the opened directory. * Optional. * @note Optional. RTVFSDIROPS::pfnOpenObj will be used if NULL. * @sa RTDirOpen. */ DECLCALLBACKMEMBER(int, pfnOpenDir,(void *pvThis, const char *pszSubDir, uint32_t fFlags, PRTVFSDIR phVfsDir)); /** * Creates a new subdirectory. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszSubDir The name of the immediate subdirectory to create. * @param fMode The mode mask of the new directory. * @param phVfsDir Where to optionally return the handle to the newly * create directory. * @note Optional. RTVFSDIROPS::pfnOpenObj will be used if NULL. * @sa RTDirCreate. */ DECLCALLBACKMEMBER(int, pfnCreateDir,(void *pvThis, const char *pszSubDir, RTFMODE fMode, PRTVFSDIR phVfsDir)); /** * Opens an existing symbolic link. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszSymlink The name of the immediate symbolic link to open. * @param phVfsSymlink Where to optionally return the handle to the * newly create symbolic link. * @note Optional. RTVFSDIROPS::pfnOpenObj will be used if NULL. * @sa RTSymlinkCreate. */ DECLCALLBACKMEMBER(int, pfnOpenSymlink,(void *pvThis, const char *pszSymlink, PRTVFSSYMLINK phVfsSymlink)); /** * Creates a new symbolic link. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszSymlink The name of the immediate symbolic link to create. * @param pszTarget The symbolic link target. * @param enmType The symbolic link type. * @param phVfsSymlink Where to optionally return the handle to the * newly create symbolic link. * @sa RTSymlinkCreate. */ DECLCALLBACKMEMBER(int, pfnCreateSymlink,(void *pvThis, const char *pszSymlink, const char *pszTarget, RTSYMLINKTYPE enmType, PRTVFSSYMLINK phVfsSymlink)); /** * Query information about an entry. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszEntry The name of the directory entry to remove. * @param pObjInfo Where to return the info on success. * @param enmAddAttr Which set of additional attributes to request. * @note Optional. RTVFSDIROPS::pfnOpenObj and RTVFSOBJOPS::pfnQueryInfo * will be used if NULL. * @sa RTPathQueryInfo, RTVFSOBJOPS::pfnQueryInfo */ DECLCALLBACKMEMBER(int, pfnQueryEntryInfo,(void *pvThis, const char *pszEntry, PRTFSOBJINFO pObjInfo, RTFSOBJATTRADD enmAddAttr)); /** * Removes a directory entry. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszEntry The name of the directory entry to remove. * @param fType If non-zero, this restricts the type of the entry to * the object type indicated by the mask * (RTFS_TYPE_XXX). * @sa RTFileRemove, RTDirRemove, RTSymlinkRemove. */ DECLCALLBACKMEMBER(int, pfnUnlinkEntry,(void *pvThis, const char *pszEntry, RTFMODE fType)); /** * Renames a directory entry. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pszEntry The name of the directory entry to rename. * @param fType If non-zero, this restricts the type of the entry to * the object type indicated by the mask * (RTFS_TYPE_XXX). * @param pszNewName The new entry name. * @sa RTPathRename * * @todo This API is not flexible enough, must be able to rename between * directories within a file system. */ DECLCALLBACKMEMBER(int, pfnRenameEntry,(void *pvThis, const char *pszEntry, RTFMODE fType, const char *pszNewName)); /** * Rewind the directory stream so that the next read returns the first * entry. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. */ DECLCALLBACKMEMBER(int, pfnRewindDir,(void *pvThis)); /** * Rewind the directory stream so that the next read returns the first * entry. * * @returns IPRT status code. * @param pvThis The implementation specific directory data. * @param pDirEntry Output buffer. * @param pcbDirEntry Complicated, see RTDirReadEx. * @param enmAddAttr Which set of additional attributes to request. * @sa RTDirReadEx */ DECLCALLBACKMEMBER(int, pfnReadDir,(void *pvThis, PRTDIRENTRYEX pDirEntry, size_t *pcbDirEntry, RTFSOBJATTRADD enmAddAttr)); /** Marks the end of the structure (RTVFSDIROPS_VERSION). */ uintptr_t uEndMarker; } RTVFSDIROPS; /** Pointer to const directory operations. */ typedef RTVFSDIROPS const *PCRTVFSDIROPS; /** The RTVFSDIROPS structure version. */ #define RTVFSDIROPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x4f,1,0) /** * Creates a new VFS directory handle. * * @returns IPRT status code * @param pDirOps The directory operations. * @param cbInstance The size of the instance data. * @param fFlags RTVFSDIR_F_XXX * @param hVfs The VFS handle to associate this directory with. * NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param phVfsDir Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNewDir(PCRTVFSDIROPS pDirOps, size_t cbInstance, uint32_t fFlags, RTVFS hVfs, RTVFSLOCK hLock, PRTVFSDIR phVfsDir, void **ppvInstance); /** @name RTVFSDIR_F_XXX * @{ */ /** Don't reference the @a hVfs parameter passed to RTVfsNewDir. * This is a permanent root directory hack. */ #define RTVFSDIR_F_NO_VFS_REF RT_BIT_32(0) /** @} */ /** * Gets the private data of a directory. * * @returns Pointer to the private data. NULL if the handle is invalid in some * way. * @param hVfsDir The directory handle. * @param pDirOps The directory operations. This servers as a * sort of password. */ RTDECL(void *) RTVfsDirToPrivate(RTVFSDIR hVfsDir, PCRTVFSDIROPS pDirOps); /** * The symbolic link operations. * * @extends RTVFSOBJOPS * @extends RTVFSOBJSETOPS */ typedef struct RTVFSSYMLINKOPS { /** The basic object operation. */ RTVFSOBJOPS Obj; /** The structure version (RTVFSSYMLINKOPS_VERSION). */ uint32_t uVersion; /** Reserved field, MBZ. */ uint32_t fReserved; /** The object setter operations. */ RTVFSOBJSETOPS ObjSet; /** * Read the symbolic link target. * * @returns IPRT status code. * @param pvThis The implementation specific symbolic link data. * @param pszTarget The target buffer. * @param cbTarget The size of the target buffer. * @sa RTSymlinkRead */ DECLCALLBACKMEMBER(int, pfnRead,(void *pvThis, char *pszTarget, size_t cbTarget)); /** Marks the end of the structure (RTVFSSYMLINKOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSSYMLINKOPS; /** Pointer to const symbolic link operations. */ typedef RTVFSSYMLINKOPS const *PCRTVFSSYMLINKOPS; /** The RTVFSSYMLINKOPS structure version. */ #define RTVFSSYMLINKOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x5f,1,0) /** * Creates a new VFS symlink handle. * * @returns IPRT status code * @param pSymlinkOps The symlink operations. * @param cbInstance The size of the instance data. * @param hVfs The VFS handle to associate this symlink object * with. NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param phVfsSym Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNewSymlink(PCRTVFSSYMLINKOPS pSymlinkOps, size_t cbInstance, RTVFS hVfs, RTVFSLOCK hLock, PRTVFSSYMLINK phVfsSym, void **ppvInstance); /** * Gets the private data of a symbolic link. * * @returns Pointer to the private data. NULL if the handle is invalid in some * way. * @param hVfsSym The symlink handle. * @param pSymlinkOps The symlink operations. This servers as a sort * of password. */ RTDECL(void *) RTVfsSymlinkToPrivate(RTVFSSYMLINK hVfsSym, PCRTVFSSYMLINKOPS pSymlinkOps); /** * The basis for all I/O objects (files, pipes, sockets, devices, ++). * * @extends RTVFSOBJOPS */ typedef struct RTVFSIOSTREAMOPS { /** The basic object operation. */ RTVFSOBJOPS Obj; /** The structure version (RTVFSIOSTREAMOPS_VERSION). */ uint32_t uVersion; /** Feature field. */ uint32_t fFeatures; /** * Reads from the file/stream. * * @returns IPRT status code. See RTVfsIoStrmRead. * @param pvThis The implementation specific file data. * @param off Where to read at, -1 for the current position. * @param pSgBuf Gather buffer describing the bytes that are to be * written. * @param fBlocking If @c true, the call is blocking, if @c false it * should not block. * @param pcbRead Where return the number of bytes actually read. * This is set it 0 by the caller. If NULL, try read * all and fail if incomplete. * @sa RTVfsIoStrmRead, RTVfsIoStrmSgRead, RTVfsFileRead, * RTVfsFileReadAt, RTFileRead, RTFileReadAt. */ DECLCALLBACKMEMBER(int, pfnRead,(void *pvThis, RTFOFF off, PCRTSGBUF pSgBuf, bool fBlocking, size_t *pcbRead)); /** * Writes to the file/stream. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param off Where to start wrinting, -1 for the current * position. * @param pSgBuf Gather buffers describing the bytes that are to be * written. * @param fBlocking If @c true, the call is blocking, if @c false it * should not block. * @param pcbWritten Where to return the number of bytes actually * written. This is set it 0 by the caller. If * NULL, try write it all and fail if incomplete. * @note Optional, failing with VERR_WRITE_PROTECT if NULL. * @sa RTFileWrite, RTFileWriteAt. */ DECLCALLBACKMEMBER(int, pfnWrite,(void *pvThis, RTFOFF off, PCRTSGBUF pSgBuf, bool fBlocking, size_t *pcbWritten)); /** * Flushes any pending data writes to the stream. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @sa RTFileFlush. */ DECLCALLBACKMEMBER(int, pfnFlush,(void *pvThis)); /** * Poll for events. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param fEvents The events to poll for (RTPOLL_EVT_XXX). * @param cMillies How long to wait for event to eventuate. * @param fIntr Whether the wait is interruptible and can return * VERR_INTERRUPTED (@c true) or if this condition * should be hidden from the caller (@c false). * @param pfRetEvents Where to return the event mask. * @note Optional. If NULL, immediately return all requested non-error * events, waiting for errors works like sleep. * @sa RTPollSetAdd, RTPoll, RTPollNoResume. */ DECLCALLBACKMEMBER(int, pfnPollOne,(void *pvThis, uint32_t fEvents, RTMSINTERVAL cMillies, bool fIntr, uint32_t *pfRetEvents)); /** * Tells the current file/stream position. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param poffActual Where to return the actual offset. * @sa RTFileTell */ DECLCALLBACKMEMBER(int, pfnTell,(void *pvThis, PRTFOFF poffActual)); /** * Skips @a cb ahead in the stream. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param cb The number bytes to skip. * @remarks This is optional and can be NULL. */ DECLCALLBACKMEMBER(int, pfnSkip,(void *pvThis, RTFOFF cb)); /** * Fills the stream with @a cb zeros. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param cb The number of zero bytes to insert. * @remarks This is optional and can be NULL. */ DECLCALLBACKMEMBER(int, pfnZeroFill,(void *pvThis, RTFOFF cb)); /** Marks the end of the structure (RTVFSIOSTREAMOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSIOSTREAMOPS; /** Pointer to const I/O stream operations. */ typedef RTVFSIOSTREAMOPS const *PCRTVFSIOSTREAMOPS; /** The RTVFSIOSTREAMOPS structure version. */ #define RTVFSIOSTREAMOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x6f,1,0) /** @name RTVFSIOSTREAMOPS::fFeatures * @{ */ /** No scatter gather lists, thank you. */ #define RTVFSIOSTREAMOPS_FEAT_NO_SG RT_BIT_32(0) /** Mask of the valid I/O stream feature flags. */ #define RTVFSIOSTREAMOPS_FEAT_VALID_MASK UINT32_C(0x00000001) /** @} */ /** * Creates a new VFS I/O stream handle. * * @returns IPRT status code * @param pIoStreamOps The I/O stream operations. * @param cbInstance The size of the instance data. * @param fOpen The open flags. The minimum is the access mask. * @param hVfs The VFS handle to associate this I/O stream * with. NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param phVfsIos Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNewIoStream(PCRTVFSIOSTREAMOPS pIoStreamOps, size_t cbInstance, uint32_t fOpen, RTVFS hVfs, RTVFSLOCK hLock, PRTVFSIOSTREAM phVfsIos, void **ppvInstance); /** * Gets the private data of an I/O stream. * * @returns Pointer to the private data. NULL if the handle is invalid in some * way. * @param hVfsIos The I/O stream handle. * @param pIoStreamOps The I/O stream operations. This servers as a * sort of password. */ RTDECL(void *) RTVfsIoStreamToPrivate(RTVFSIOSTREAM hVfsIos, PCRTVFSIOSTREAMOPS pIoStreamOps); /** * The file operations. * * @extends RTVFSIOSTREAMOPS * @extends RTVFSOBJSETOPS */ typedef struct RTVFSFILEOPS { /** The I/O stream and basis object operations. */ RTVFSIOSTREAMOPS Stream; /** The structure version (RTVFSFILEOPS_VERSION). */ uint32_t uVersion; /** Reserved field, MBZ. */ uint32_t fReserved; /** The object setter operations. */ RTVFSOBJSETOPS ObjSet; /** * Changes the current file position. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param offSeek The offset to seek. * @param uMethod The seek method, i.e. what the seek is relative to. * @param poffActual Where to return the actual offset. * @sa RTFileSeek */ DECLCALLBACKMEMBER(int, pfnSeek,(void *pvThis, RTFOFF offSeek, unsigned uMethod, PRTFOFF poffActual)); /** * Get the current file size. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param pcbFile Where to store the current file size. * @sa RTFileQuerySize */ DECLCALLBACKMEMBER(int, pfnQuerySize,(void *pvThis, uint64_t *pcbFile)); /** * Change the file size. * * @returns IPRT status code. * @retval VERR_ACCESS_DENIED if handle isn't writable. * @retval VERR_WRITE_PROTECT if read-only file system. * @retval VERR_FILE_TOO_BIG if cbSize is larger than what the file system can * theoretically deal with. * @retval VERR_DISK_FULL if the file system if full. * @retval VERR_NOT_SUPPORTED if fFlags indicates some operation that's not * supported by the file system / host operating system. * * @param pvThis The implementation specific file data. * @param pcbFile Where to store the current file size. * @param fFlags RTVFSFILE_SET_SIZE_F_XXX. * @note Optional. If NULL, VERR_WRITE_PROTECT will be returned. * @sa RTFileSetSize, RTFileSetAllocationSize */ DECLCALLBACKMEMBER(int, pfnSetSize,(void *pvThis, uint64_t cbFile, uint32_t fFlags)); /** * Determine the maximum file size. * * This won't take amount of freespace into account, just the limitations of the * underlying file system / host operating system. * * @returns IPRT status code. * @param pvThis The implementation specific file data. * @param pcbMax Where to return the max file size. * @note Optional. If NULL, VERR_NOT_IMPLEMENTED will be returned. * @sa RTFileQueryMaxSizeEx */ DECLCALLBACKMEMBER(int, pfnQueryMaxSize,(void *pvThis, uint64_t *pcbMax)); /** @todo There will be more methods here. */ /** Marks the end of the structure (RTVFSFILEOPS_VERSION). */ uintptr_t uEndMarker; } RTVFSFILEOPS; /** Pointer to const file operations. */ typedef RTVFSFILEOPS const *PCRTVFSFILEOPS; /** The RTVFSFILEOPS structure version. */ #define RTVFSFILEOPS_VERSION RT_MAKE_U32_FROM_U8(0xff,0x7f,2,0) /** * Creates a new VFS file handle. * * @returns IPRT status code * @param pFileOps The file operations. * @param cbInstance The size of the instance data. * @param fOpen The open flags. The minimum is the access mask. * @param hVfs The VFS handle to associate this file with. * NIL_VFS is ok. * @param hLock Handle to a custom lock to be used with the new * object. The reference is consumed. NIL and * special lock handles are fine. * @param phVfsFile Where to return the new handle. * @param ppvInstance Where to return the pointer to the instance data * (size is @a cbInstance). */ RTDECL(int) RTVfsNewFile(PCRTVFSFILEOPS pFileOps, size_t cbInstance, uint32_t fOpen, RTVFS hVfs, RTVFSLOCK hLock, PRTVFSFILE phVfsFile, void **ppvInstance); /** @defgroup grp_rt_vfs_ll_util VFS Utility APIs * @{ */ /** * Parsed path. */ typedef struct RTVFSPARSEDPATH { /** The length of the path in szCopy. */ uint16_t cch; /** The number of path components. */ uint16_t cComponents; /** Set if the path ends with slash, indicating that it's a directory * reference and not a file reference. The slash has been removed from * the copy. */ bool fDirSlash; /** Set if absolute. */ bool fAbsolute; /** The offset where each path component starts, i.e. the char after the * slash. The array has cComponents + 1 entries, where the final one is * cch + 1 so that one can always terminate the current component by * szPath[aoffComponent[i] - 1] = '\0'. */ uint16_t aoffComponents[RTPATH_MAX / 2 + 1]; /** A normalized copy of the path. * Reserve some extra space so we can be more relaxed about overflow * checks and terminator paddings, especially when recursing. */ char szPath[RTPATH_MAX]; } RTVFSPARSEDPATH; /** Pointer to a parsed path. */ typedef RTVFSPARSEDPATH *PRTVFSPARSEDPATH; /** The max accepted path length. * This must be a few chars shorter than RTVFSPARSEDPATH::szPath because we * use two terminators and wish be a little bit lazy with checking. */ #define RTVFSPARSEDPATH_MAX (RTPATH_MAX - 4) /** * Appends @a pszPath (relative) to the already parsed path @a pPath. * * @retval VINF_SUCCESS * @retval VERR_FILENAME_TOO_LONG * @retval VERR_INTERNAL_ERROR_4 * @param pPath The parsed path to append @a pszPath onto. * This is both input and output. * @param pszPath The path to append. This must be relative. * @param piRestartComp The component to restart parsing at. This is * input/output. The input does not have to be * within the valid range. Optional. */ RTDECL(int) RTVfsParsePathAppend(PRTVFSPARSEDPATH pPath, const char *pszPath, uint16_t *piRestartComp); /** * Parses a path. * * @retval VINF_SUCCESS * @retval VERR_FILENAME_TOO_LONG * @param pPath Where to store the parsed path. * @param pszPath The path to parse. Absolute or relative to @a * pszCwd. * @param pszCwd The current working directory. Must be * absolute. */ RTDECL(int) RTVfsParsePath(PRTVFSPARSEDPATH pPath, const char *pszPath, const char *pszCwd); /** * Same as RTVfsParsePath except that it allocates a temporary buffer. * * @retval VINF_SUCCESS * @retval VERR_NO_TMP_MEMORY * @retval VERR_FILENAME_TOO_LONG * @param pszPath The path to parse. Absolute or relative to @a * pszCwd. * @param pszCwd The current working directory. Must be * absolute. * @param ppPath Where to store the pointer to the allocated * buffer containing the parsed path. This must * be freed by calling RTVfsParsePathFree. NULL * will be stored on failured. */ RTDECL(int) RTVfsParsePathA(const char *pszPath, const char *pszCwd, PRTVFSPARSEDPATH *ppPath); /** * Frees a buffer returned by RTVfsParsePathA. * * @param pPath The parsed path buffer to free. NULL is fine. */ RTDECL(void) RTVfsParsePathFree(PRTVFSPARSEDPATH pPath); /** * Dummy implementation of RTVFSIOSTREAMOPS::pfnPollOne. * * This handles the case where there is no chance any events my be raised and * all that is required is to wait according to the parameters. * * @returns IPRT status code. * @param fEvents The events to poll for (RTPOLL_EVT_XXX). * @param cMillies How long to wait for event to eventuate. * @param fIntr Whether the wait is interruptible and can return * VERR_INTERRUPTED (@c true) or if this condition * should be hidden from the caller (@c false). * @param pfRetEvents Where to return the event mask. * @sa RTVFSIOSTREAMOPS::pfnPollOne, RTPollSetAdd, RTPoll, RTPollNoResume. */ RTDECL(int) RTVfsUtilDummyPollOne(uint32_t fEvents, RTMSINTERVAL cMillies, bool fIntr, uint32_t *pfRetEvents); /** @} */ /** @defgroup grp_rt_vfs_lowlevel_chain VFS Chains (Low Level) * @ref grp_rt_vfs_chain * @{ */ /** Pointer to a VFS chain element registration record. */ typedef struct RTVFSCHAINELEMENTREG *PRTVFSCHAINELEMENTREG; /** Pointer to a const VFS chain element registration record. */ typedef struct RTVFSCHAINELEMENTREG const *PCRTVFSCHAINELEMENTREG; /** * VFS chain element argument. */ typedef struct RTVFSCHAINELEMENTARG { /** The string argument value. */ char *psz; /** The specification offset of this argument. */ uint16_t offSpec; /** Provider specific value. */ uint64_t uProvider; } RTVFSCHAINELEMENTARG; /** Pointer to a VFS chain element argument. */ typedef RTVFSCHAINELEMENTARG *PRTVFSCHAINELEMENTARG; /** * VFS chain element specification. */ typedef struct RTVFSCHAINELEMSPEC { /** The provider name. * This can be NULL if this is the final component and it's just a path. */ char *pszProvider; /** The input type, RTVFSOBJTYPE_INVALID if first. */ RTVFSOBJTYPE enmTypeIn; /** The element type. * RTVFSOBJTYPE_END if this is the final component and it's just a path. */ RTVFSOBJTYPE enmType; /** The input spec offset of this element. */ uint16_t offSpec; /** The length of the input spec. */ uint16_t cchSpec; /** The number of arguments. */ uint32_t cArgs; /** Arguments. */ PRTVFSCHAINELEMENTARG paArgs; /** The provider. */ PCRTVFSCHAINELEMENTREG pProvider; /** Provider specific value. */ uint64_t uProvider; /** The object (with reference). */ RTVFSOBJ hVfsObj; } RTVFSCHAINELEMSPEC; /** Pointer to a chain element specification. */ typedef RTVFSCHAINELEMSPEC *PRTVFSCHAINELEMSPEC; /** Pointer to a const chain element specification. */ typedef RTVFSCHAINELEMSPEC const *PCRTVFSCHAINELEMSPEC; /** * Parsed VFS chain specification. */ typedef struct RTVFSCHAINSPEC { /** Open directory flags (RTFILE_O_XXX). */ uint64_t fOpenFile; /** To be defined. */ uint32_t fOpenDir; /** The type desired by the caller. */ RTVFSOBJTYPE enmDesiredType; /** The number of elements. */ uint32_t cElements; /** The elements. */ PRTVFSCHAINELEMSPEC paElements; } RTVFSCHAINSPEC; /** Pointer to a parsed VFS chain specification. */ typedef RTVFSCHAINSPEC *PRTVFSCHAINSPEC; /** Pointer to a const, parsed VFS chain specification. */ typedef RTVFSCHAINSPEC const *PCRTVFSCHAINSPEC; /** * A chain element provider registration record. */ typedef struct RTVFSCHAINELEMENTREG { /** The version (RTVFSCHAINELEMENTREG_VERSION). */ uint32_t uVersion; /** Reserved, MBZ. */ uint32_t fReserved; /** The provider name (unique). */ const char *pszName; /** For chaining the providers. */ RTLISTNODE ListEntry; /** Help text. */ const char *pszHelp; /** * Checks the element specification. * * This is allowed to parse arguments and use pSpec->uProvider and * pElement->paArgs[].uProvider to store information that pfnInstantiate and * pfnCanReuseElement may use later on, thus avoiding duplicating work/code. * * @returns IPRT status code. * @param pProviderReg Pointer to the element provider registration. * @param pSpec The chain specification. * @param pElement The chain element specification to validate. * @param poffError Where to return error offset on failure. This is * set to the pElement->offSpec on input, so it only * needs to be adjusted if an argument is at fault. * @param pErrInfo Where to return additional error information, if * available. Optional. */ DECLCALLBACKMEMBER(int, pfnValidate,(PCRTVFSCHAINELEMENTREG pProviderReg, PRTVFSCHAINSPEC pSpec, PRTVFSCHAINELEMSPEC pElement, uint32_t *poffError, PRTERRINFO pErrInfo)); /** * Create a VFS object according to the element specification. * * @returns IPRT status code. * @param pProviderReg Pointer to the element provider registration. * @param pSpec The chain specification. * @param pElement The chain element specification to instantiate. * @param hPrevVfsObj Handle to the previous VFS object, NIL_RTVFSOBJ if * first. * @param phVfsObj Where to return the VFS object handle. * @param poffError Where to return error offset on failure. This is * set to the pElement->offSpec on input, so it only * needs to be adjusted if an argument is at fault. * @param pErrInfo Where to return additional error information, if * available. Optional. */ DECLCALLBACKMEMBER(int, pfnInstantiate,(PCRTVFSCHAINELEMENTREG pProviderReg, PCRTVFSCHAINSPEC pSpec, PCRTVFSCHAINELEMSPEC pElement, RTVFSOBJ hPrevVfsObj, PRTVFSOBJ phVfsObj, uint32_t *poffError, PRTERRINFO pErrInfo)); /** * Determins whether the element can be reused. * * This is for handling situations accessing the same file system twice, like * for both the source and destiation of a copy operation. This allows not only * sharing resources and avoid doing things twice, but also helps avoid file * sharing violations and inconsistencies araising from the image being updated * and read independently. * * @returns true if the element from @a pReuseSpec an be reused, false if not. * @param pProviderReg Pointer to the element provider registration. * @param pSpec The chain specification. * @param pElement The chain element specification. * @param pReuseSpec The chain specification of the existing chain. * @param pReuseElement The chain element specification of the existing * element that is being considered for reuse. */ DECLCALLBACKMEMBER(bool, pfnCanReuseElement,(PCRTVFSCHAINELEMENTREG pProviderReg, PCRTVFSCHAINSPEC pSpec, PCRTVFSCHAINELEMSPEC pElement, PCRTVFSCHAINSPEC pReuseSpec, PCRTVFSCHAINELEMSPEC pReuseElement)); /** End marker (RTVFSCHAINELEMENTREG_VERSION). */ uintptr_t uEndMarker; } RTVFSCHAINELEMENTREG; /** The VFS chain element registration record version number. */ #define RTVFSCHAINELEMENTREG_VERSION RT_MAKE_U32_FROM_U8(0xff, 0x7f, 1, 0) /** * Parses the specification. * * @returns IPRT status code. * @param pszSpec The specification string to parse. * @param fFlags Flags, see RTVFSCHAIN_PF_XXX. * @param enmDesiredType The object type the caller wants to interface with. * @param ppSpec Where to return the pointer to the parsed * specification. This must be freed by calling * RTVfsChainSpecFree. Will always be set (unless * invalid parameters.) * @param poffError Where to return the offset into the input * specification of what's causing trouble. Always * set, unless this argument causes an invalid pointer * error. */ RTDECL(int) RTVfsChainSpecParse(const char *pszSpec, uint32_t fFlags, RTVFSOBJTYPE enmDesiredType, PRTVFSCHAINSPEC *ppSpec, uint32_t *poffError); /** @name RTVfsChainSpecParse * @{ */ /** Mask of valid flags. */ #define RTVFSCHAIN_PF_VALID_MASK UINT32_C(0x00000000) /** @} */ /** * Checks and setups the chain. * * @returns IPRT status code. * @param pSpec The parsed specification. * @param pReuseSpec Spec to reuse if applicable. Optional. * @param phVfsObj Where to return the VFS object. * @param ppszFinalPath Where to return the pointer to the final path if * applicable. The caller needs to check whether this * is NULL or a path, in the former case nothing more * needs doing, whereas in the latter the caller must * perform the desired operation(s) on *phVfsObj using * the final path. * @param poffError Where to return the offset into the input * specification of what's causing trouble. Always * set, unless this argument causes an invalid pointer * error. * @param pErrInfo Where to return additional error information, if * available. Optional. */ RTDECL(int) RTVfsChainSpecCheckAndSetup(PRTVFSCHAINSPEC pSpec, PCRTVFSCHAINSPEC pReuseSpec, PRTVFSOBJ phVfsObj, const char **ppszFinalPath, uint32_t *poffError, PRTERRINFO pErrInfo); /** * Frees a parsed chain specification. * * @param pSpec What RTVfsChainSpecParse returned. NULL is * quietly ignored. */ RTDECL(void) RTVfsChainSpecFree(PRTVFSCHAINSPEC pSpec); /** * Registers a chain element provider. * * @returns IPRT status code * @param pRegRec The registration record. * @param fFromCtor Indicates where we're called from. */ RTDECL(int) RTVfsChainElementRegisterProvider(PRTVFSCHAINELEMENTREG pRegRec, bool fFromCtor); /** * Deregisters a chain element provider. * * @returns IPRT status code * @param pRegRec The registration record. * @param fFromDtor Indicates where we're called from. */ RTDECL(int) RTVfsChainElementDeregisterProvider(PRTVFSCHAINELEMENTREG pRegRec, bool fFromDtor); /** @def RTVFSCHAIN_AUTO_REGISTER_ELEMENT_PROVIDER * Automatically registers a chain element provider using a global constructor * and destructor hack. * * @param pRegRec Pointer to the registration record. * @param name Some unique variable name prefix. */ #ifdef __cplusplus /** * Class used for registering a VFS chain element provider. */ class RTVfsChainElementAutoRegisterHack { private: /** The registration record, NULL if registration failed. */ PRTVFSCHAINELEMENTREG m_pRegRec; public: RTVfsChainElementAutoRegisterHack(PRTVFSCHAINELEMENTREG a_pRegRec) : m_pRegRec(a_pRegRec) { int rc = RTVfsChainElementRegisterProvider(m_pRegRec, true); if (RT_FAILURE(rc)) m_pRegRec = NULL; } ~RTVfsChainElementAutoRegisterHack() { RTVfsChainElementDeregisterProvider(m_pRegRec, true); m_pRegRec = NULL; } }; # define RTVFSCHAIN_AUTO_REGISTER_ELEMENT_PROVIDER(pRegRec, name) \ static RTVfsChainElementAutoRegisterHack name ## AutoRegistrationHack(pRegRec) #else # define RTVFSCHAIN_AUTO_REGISTER_ELEMENT_PROVIDER(pRegRec, name) \ extern void *name ## AutoRegistrationHack = \ &Sorry_but_RTVFSCHAIN_AUTO_REGISTER_ELEMENT_PROVIDER_does_not_work_in_c_source_files #endif /** * Common worker for the 'stdfile' and 'open' providers for implementing * RTVFSCHAINELEMENTREG::pfnValidate. * * Stores the RTFILE_O_XXX flags in pSpec->uProvider. * * @returns IPRT status code. * @param pSpec The chain specification. * @param pElement The chain element specification to validate. * @param poffError Where to return error offset on failure. This is set to * the pElement->offSpec on input, so it only needs to be * adjusted if an argument is at fault. * @param pErrInfo Where to return additional error information, if * available. Optional. */ RTDECL(int) RTVfsChainValidateOpenFileOrIoStream(PRTVFSCHAINSPEC pSpec, PRTVFSCHAINELEMSPEC pElement, uint32_t *poffError, PRTERRINFO pErrInfo); /** @} */ /** @} */ RT_C_DECLS_END #endif /* !IPRT_INCLUDED_vfslowlevel_h */