From: Eric Biggers Date: Sat, 24 May 2014 02:43:19 +0000 (-0500) Subject: Update mount implementation X-Git-Tag: v1.7.0~109 X-Git-Url: https://wimlib.net/git/?p=wimlib;a=commitdiff_plain;h=d444f2e5ddee51e7d9d0401cffcf88477c180422 Update mount implementation - Improve comments and documentation - Speed up fd allocation by tracking lower bound on next available slot - Open staging files by directory-relative names - Simplify, and hopefully improve, how unmounting images works. --- diff --git a/doc/man1/imagex-mount.1.in b/doc/man1/imagex-mount.1.in index f475527c..2f3e0618 100644 --- a/doc/man1/imagex-mount.1.in +++ b/doc/man1/imagex-mount.1.in @@ -6,7 +6,7 @@ .br \fB@IMAGEX_PROGNAME@ mountrw\fR \fIWIMFILE\fR [\fIIMAGE\fR] \fIDIRECTORY\fR [\fIOPTION\fR...] .br -\fB@IMAGEX_PROGNAME@ unmount\fR \fIDIRECTORY\fR [--commit] [--check] [--rebuild] +\fB@IMAGEX_PROGNAME@ unmount\fR \fIDIRECTORY\fR [\fIOPTION\fR...] .SH DESCRIPTION The \fB@IMAGEX_PROGNAME@ mount\fR and \fB@IMAGEX_PROGNAME@ mountrw\fR commands will mount the image in the Windows Imaging (WIM) file \fIWIMFILE\fR specified @@ -21,9 +21,9 @@ be the name of an image in the WIM. Use the \fB@IMAGEX_PROGNAME@ info\fR (1) command to see the available images in the WIM. \fIIMAGE\fR may be omitted if \fIWIMFILE\fR contains only one image. .PP -The WIM image can be unmounted using the \fB@IMAGEX_PROGNAME@ unmount\fR command. Changes -made to a WIM mounted read-write will be discarded unless the \fB--commit\fR -flag is provided to \fB@IMAGEX_PROGNAME@ unmount\fR. +The WIM image can be unmounted using the \fB@IMAGEX_PROGNAME@ unmount\fR +command. Changes made to a WIM mounted read-write will be discarded unless the +\fB--commit\fR flag is provided to \fB@IMAGEX_PROGNAME@ unmount\fR. .SH SPLIT WIMS You may use \fB@IMAGEX_PROGNAME@ mount\fR to mount an image from a split WIM read-only. However, you may not mount an image from a split WIM read-write. @@ -62,16 +62,16 @@ All files in the mounted WIM will be accessible regardless of whether there is a security descriptor in the WIM associated with the file or not. New files or directories created in a read-write mounted WIM will be created with no security descriptor. Although there is support for accessing named data streams (see the -\fB--streams-interface\fR option), it is currently not possible -to set or get DOS names, file attributes, or security -descriptors in a mounted WIM. +\fB--streams-interface\fR option), it is currently not possible to set or get +DOS names, file attributes, or security descriptors in a mounted WIM. .PP By default, changes to a read-write WIM are made in-place by appending to the WIM. This is nice for big WIM files, since the entire file doesn't have to be rebuilt to make a small change. But, if you are making many changes to a read-write mounted WIM, especially deleting large files, it is suggested to -provide the \fB--rebuild\fR option to \fB@IMAGEX_PROGNAME@ unmount\fR to force the WIM to -be rebuilt, or else run \fB@IMAGEX_PROGNAME@ optimize\fR on the WIM afterwards. +provide the \fB--rebuild\fR option to \fB@IMAGEX_PROGNAME@ unmount\fR to force +the WIM to be rebuilt, or else run \fB@IMAGEX_PROGNAME@ optimize\fR on the WIM +afterwards. .PP wimlib v1.6.0 and later can mount version 3584 WIMs, which usually use packed, LZMS-compressed streams and may carry the \fI.esd\fR file extension rather than @@ -148,6 +148,15 @@ specified in /etc/fuse.conf (with the FUSE implementation on Linux, at least). Update the WIM file with the changes that have been made. Has no effect if the mount is read-only. .TP +\fB--force\fR +In combination with \fB--commit\fR, force the WIM image to be committed even if +there are open file descriptors to the WIM image. Any such file descriptors +will be immediately closed, and the WIM image will be committed and unmounted. +.IP +\fB--lazy\fR is a deprecated alias for \fB--force\fR. (Unmounts are now "lazy" +by default with regards to the kernel-level mountpoint, except in the case with +\fB--commit\fR described above.) +.TP \fB--check\fR When writing \fIWIMFILE\fR, include an integrity table. Has no effect if the mount is read-only or if \fB--commit\fR was not specified. The default behavior @@ -159,28 +168,23 @@ Rebuilding the WIM is slower, but will save a little bit of space that would otherwise be left as a hole in the WIM. Even more space will be saved if the read-write mount resulted in streams being deleted from the WIM. Also see .TP -\fB--lazy\fR -Pass the \fB-z\fR option to \fBfusermount\fR, which performs a "lazy" unmount -where the filesystem is detached immediately even if it is still busy. However, -even with this option, \fB@IMAGEX_PROGNAME@ unmount\fR still waits for the -filesystem to become unbusy; \fB--lazy\fR will only stop the unmount from -immediately failing. -.TP \fB--new-image\fR In combination with \fB--commit\fR for a read-write mounted image, causes the modified image to be committed as a new, unnamed image appended to the WIM archive. The original image will be unmodified. .SH IMPLEMENTATION DETAILS -Since a WIM is an archive and not a filesystem, \fB@IMAGEX_PROGNAME@ mountrw\fR creates a -temporary staging directory to contain files that are created or modified. This -directory is located in the same directory as \fIWIMFILE\fR by default, but the -location can be set using the \fB--staging-dir\fR option. When the filesystem -is unmounted with \fB--commit\fR, the WIM is modified in-place (or rebuild -completely with \fB--rebuild\fR), merging in the staging files as needed. Then, -the temporary staging directory is deleted. +Since a WIM is an archive and not a filesystem, \fB@IMAGEX_PROGNAME@ mountrw\fR +creates a temporary staging directory to contain files that are created or +modified. This directory is located in the same directory as \fIWIMFILE\fR by +default, but the location can be set using the \fB--staging-dir\fR option. When +the filesystem is unmounted with \fB--commit\fR, the WIM is modified in-place +(or rebuilt completely with \fB--rebuild\fR), merging in the staging files as +needed. Then, the temporary staging directory is deleted. .PP -\fB@IMAGEX_PROGNAME@ unmount\fR runs in a separate process from the process that previously -ran \fB@IMAGEX_PROGNAME@ mount\fR, and these two processes communicate using POSIX message -queues. See \fIsrc/mount_image.c\fR in the sources for details. +\fB@IMAGEX_PROGNAME@ unmount\fR runs in a separate process from the process that +previously ran \fB@IMAGEX_PROGNAME@ mount\fR. When unmounting a read-write +mounted WIM image with \fB--commit\fR, these two processes communicate using a +POSIX message queue so that the unmount process can track the progress of the +mount process. See \fIsrc/mount_image.c\fR in the sources for details. .SH SEE ALSO .BR @IMAGEX_PROGNAME@ (1) diff --git a/include/wimlib.h b/include/wimlib.h index ea15d8e7..ea48aaef 100644 --- a/include/wimlib.h +++ b/include/wimlib.h @@ -572,9 +572,13 @@ enum wimlib_progress_msg { * a file is being extracted normally (not as a WIMBoot "pointer file") * due to it matching a pattern in the [PrepopulateList] section of the * configuration file \Windows\System32\WimBootCompress.ini in the WIM - * image. @info will point to ::wimlib_progress_info.wimboot_exclude. + * image. @p info will point to ::wimlib_progress_info.wimboot_exclude. */ WIMLIB_PROGRESS_MSG_WIMBOOT_EXCLUDE = 24, + + /** Starting to unmount a WIM image. @p info will point to + * ::wimlib_progress_info.unmount. */ + WIMLIB_PROGRESS_MSG_UNMOUNT_BEGIN = 25, }; /** Valid return values from user-provided progress functions @@ -961,6 +965,25 @@ union wimlib_progress_info { /** Path to which the file is being extracted */ const wimlib_tchar *extraction_path; } wimboot_exclude; + + /** Valid on messages ::WIMLIB_PROGRESS_MSG_UNMOUNT_BEGIN. */ + struct wimlib_progress_info_unmount { + /** Path to directory being unmounted */ + const wimlib_tchar *mountpoint; + + /** Path to WIM file being unmounted */ + const wimlib_tchar *mounted_wim; + + /** 1-based index of image being unmounted. */ + uint32_t mounted_image; + + /** Flags that were passed to wimlib_mount_image() when the + * mountpoint was set up. */ + uint32_t mount_flags; + + /** Flags passed to wimlib_unmount_image(). */ + uint32_t unmount_flags; + } unmount; }; /** @@ -1604,23 +1627,24 @@ typedef int (*wimlib_iterate_lookup_table_callback_t)(const struct wimlib_resour /** Enable FUSE debugging by passing the @c -d flag to @c fuse_main().*/ #define WIMLIB_MOUNT_FLAG_DEBUG 0x00000002 -/** Do not allow accessing alternate data streams in the mounted WIM image. */ +/** Do not allow accessing named data streams in the mounted WIM image. */ #define WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_NONE 0x00000004 -/** Access alternate data streams in the mounted WIM image through extended file - * attributes. This is the default mode. */ +/** Access named data streams in the mounted WIM image through extended file + * attributes named "user.X", where X is the name of a data stream. This is the + * default mode. */ #define WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR 0x00000008 -/** Access alternate data streams in the mounted WIM image by specifying the - * file name, a colon, then the alternate file stream name. */ +/** Access named data streams in the mounted WIM image by specifying the file + * name, a colon, then the name of the data stream. */ #define WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS 0x00000010 -/** Use UNIX file owners, groups, and modes if available in the WIM (see - * ::WIMLIB_ADD_FLAG_UNIX_DATA). */ +/** Use UNIX metadata if available in the WIM image. See + * ::WIMLIB_ADD_FLAG_UNIX_DATA. */ #define WIMLIB_MOUNT_FLAG_UNIX_DATA 0x00000020 -/** Allow other users to see the mounted filesystem. (this passes the @c - * allow_other option to FUSE mount) */ +/** Allow other users to see the mounted filesystem. This passes the @c + * allow_other option to the FUSE mount. */ #define WIMLIB_MOUNT_FLAG_ALLOW_OTHER 0x00000040 /** @} */ @@ -1652,25 +1676,36 @@ typedef int (*wimlib_iterate_lookup_table_callback_t)(const struct wimlib_resour /** @ingroup G_mounting_wim_images * @{ */ -/** See ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY. */ +/** Provide ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY when committing the WIM image. + * Ignored if ::WIMLIB_UNMOUNT_FLAG_COMMIT not also specified. */ #define WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY 0x00000001 -/** Unless this flag is given, changes to a read-write mounted WIM are - * discarded. Ignored for read-only mounts. */ +/** Commit changes to the read-write mounted WIM image. + * If this flag is not specified, changes will be discarded. */ #define WIMLIB_UNMOUNT_FLAG_COMMIT 0x00000002 -/** See ::WIMLIB_WRITE_FLAG_REBUILD. */ +/** Provide ::WIMLIB_WRITE_FLAG_REBUILD when committing the WIM image. + * Ignored if ::WIMLIB_UNMOUNT_FLAG_COMMIT not also specified. */ #define WIMLIB_UNMOUNT_FLAG_REBUILD 0x00000004 -/** See ::WIMLIB_WRITE_FLAG_RECOMPRESS */ +/** Provide ::WIMLIB_WRITE_FLAG_RECOMPRESS when committing the WIM image. + * Ignored if ::WIMLIB_UNMOUNT_FLAG_COMMIT not also specified. */ #define WIMLIB_UNMOUNT_FLAG_RECOMPRESS 0x00000008 -/** Do a "lazy" unmount (detach filesystem immediately, even if busy). */ -#define WIMLIB_UNMOUNT_FLAG_LAZY 0x00000010 +/** + * In combination with ::WIMLIB_UNMOUNT_FLAG_COMMIT for a read-write mounted WIM + * image, forces all file descriptors to the open WIM image to be closed before + * committing it. + * + * Without ::WIMLIB_UNMOUNT_FLAG_COMMIT or with a read-only mounted WIM image, + * this flag has no effect. + */ +#define WIMLIB_UNMOUNT_FLAG_FORCE 0x00000010 /** In combination with ::WIMLIB_UNMOUNT_FLAG_COMMIT for a read-write mounted - * image, causes the modified image to be committed as a new, unnamed image - * appended to the archive. The original image will be unmodified. */ + * WIM image, causes the modified image to be committed to the WIM file as a + * new, unnamed image appended to the archive. The original image in the WIM + * file will be unmodified. */ #define WIMLIB_UNMOUNT_FLAG_NEW_IMAGE 0x00000020 /** @} */ @@ -2076,6 +2111,9 @@ enum wimlib_error_code { WIMLIB_ERR_ABORTED_BY_PROGRESS, WIMLIB_ERR_UNKNOWN_PROGRESS_STATUS, WIMLIB_ERR_MKNOD, + WIMLIB_ERR_MOUNTED_IMAGE_IS_BUSY, + WIMLIB_ERR_NOT_A_MOUNTPOINT, + WIMLIB_ERR_NOT_PERMITTED_TO_UNMOUNT, }; @@ -3062,82 +3100,75 @@ wimlib_join_with_progress(const wimlib_tchar * const *swms, /** * @ingroup G_mounting_wim_images * - * Mounts an image in a WIM file on a directory read-only or read-write. - * - * As this is implemented using FUSE (Filesystme in UserSpacE), this is not - * supported if wimlib was configured with @c --without-fuse. This includes - * Windows builds of wimlib; ::WIMLIB_ERR_UNSUPPORTED will be returned in such - * cases. - * - * Calling this function daemonizes the process, unless - * ::WIMLIB_MOUNT_FLAG_DEBUG was specified or an early occur occurs. If the - * mount is read-write (::WIMLIB_MOUNT_FLAG_READWRITE specified), modifications - * to the WIM are staged in a temporary directory. - * - * It is safe to mount multiple images from the same underlying WIM file - * read-only at the same time, but only if different ::WIMStruct's are used. It - * is @b not safe to mount multiple images from the same WIM file read-write at - * the same time. - * - * wimlib_mount_image() cannot be used on an image that was exported with - * wimlib_export_image() while the dentry trees for both images are still in - * memory. In addition, wimlib_mount_image() may not be used to mount an image - * that already has modifications pending (e.g. an image added with - * wimlib_add_image()). + * Mounts an image from a WIM file on a directory read-only or read-write. * * @param wim * Pointer to the ::WIMStruct containing the image to be mounted. * @param image - * The number of the image to mount, indexed starting from it. It must be - * an existing, single image. + * The 1-based index of the image to mount. * @param dir - * The path to an existing empty directory to mount the image on. + * The path to an existing empty directory on which to mount the WIM image. * @param mount_flags - * Bitwise OR of flags prefixed with WIMLIB_MOUNT_FLAG. + * Bitwise OR of flags prefixed with WIMLIB_MOUNT_FLAG. Use + * ::WIMLIB_MOUNT_FLAG_READWRITE to request a read-write mount instead of a + * read-only mount. * @param staging_dir - * If non-NULL, the name of a directory in which the staging directory will - * be created. Ignored if ::WIMLIB_MOUNT_FLAG_READWRITE is not specified - * in @p mount_flags. If left @c NULL, the staging directory is created in - * the same directory as the WIM file that @p wim was originally read from. + * If non-NULL, the name of a directory in which a temporary directory for + * storing modified or added files will be created. Ignored if + * ::WIMLIB_MOUNT_FLAG_READWRITE is not specified in @p mount_flags. If + * left @c NULL, the staging directory is created in the same directory as + * the WIM file that @p wim was originally read from. The staging + * directory is deleted when the image is unmounted. * - * @return 0 on success; nonzero on error. + * @return 0 on success; nonzero on error. The possible error codes include: * * @retval ::WIMLIB_ERR_ALREADY_LOCKED - * A read-write mount was requested, but an exclusive advisory lock on - * the on-disk WIM file could not be acquired because another thread or - * process has mounted an image from the WIM read-write or is currently - * modifying the WIM in-place. + * An image from the WIM file is already mounted read-write, or another + * process is currently appending data to the WIM file. * @retval ::WIMLIB_ERR_FUSE - * A non-zero status was returned by @c fuse_main(). + * A non-zero status code was returned by @c fuse_main(). * @retval ::WIMLIB_ERR_INVALID_IMAGE * @p image does not specify an existing, single image in @p wim. * @retval ::WIMLIB_ERR_INVALID_PARAM - * @p image is shared among multiple ::WIMStruct's as a result of a call to - * wimlib_export_image(), or @p image has been added with - * wimlib_add_image(). + * @p wim was @c NULL; or @p dir was NULL or the empty string; or an + * unrecognized flag was specified in @p mount_flags; or the WIM image has + * already been modified in memory (e.g. by wimlib_update_image()). * @retval ::WIMLIB_ERR_MKDIR * ::WIMLIB_MOUNT_FLAG_READWRITE was specified in @p mount_flags, but the * staging directory could not be created. - * @retval ::WIMLIB_ERR_NOTDIR - * Could not determine the current working directory. - * @retval ::WIMLIB_ERR_RESOURCE_NOT_FOUND - * One of the dentries in the image referenced a stream not present in the - * WIM's lookup table (or in any of the lookup tables of the split WIM - * parts). * @retval ::WIMLIB_ERR_WIM_IS_READONLY - * ::WIMLIB_MOUNT_FLAG_READWRITE was specified in @p mount_flags, but @p - * wim is considered read-only because of any of the reasons mentioned in - * the documentation for the ::WIMLIB_OPEN_FLAG_WRITE_ACCESS flag. + * ::WIMLIB_MOUNT_FLAG_READWRITE was specified in @p mount_flags, but the + * WIM file is considered read-only because of any of the reasons mentioned + * in the documentation for the ::WIMLIB_OPEN_FLAG_WRITE_ACCESS flag. * @retval ::WIMLIB_ERR_UNSUPPORTED * Mounting is not supported, either because the platform is Windows, or - * because the platform is UNIX-like and wimlib was compiled with @c - * --without-fuse. + * because the platform is UNIX-like and wimlib was compiled using + * --without-fuse. * * This function can additionally return ::WIMLIB_ERR_DECOMPRESSION, * ::WIMLIB_ERR_INVALID_METADATA_RESOURCE, ::WIMLIB_ERR_METADATA_NOT_FOUND, * ::WIMLIB_ERR_NOMEM, ::WIMLIB_ERR_READ, or * ::WIMLIB_ERR_UNEXPECTED_END_OF_FILE, all of which indicate failure (for * different reasons) to read the metadata resource for the image to mount. + * + * The ability to mount WIM image is implemented using FUSE (Filesystem in + * UserSpacE). Depending on how FUSE is set up on your system, this function + * may work as normal users in addition to the root user. + * + * Mounting WIM images is not supported if wimlib was configured + * --without-fuse. This includes Windows builds of wimlib; + * ::WIMLIB_ERR_UNSUPPORTED will be returned in such cases. + * + * Calling this function daemonizes the process, unless + * ::WIMLIB_MOUNT_FLAG_DEBUG was specified or an early error occurs. + * + * It is safe to mount multiple images from the same underlying WIM file + * read-only at the same time, but only if different ::WIMStruct's are used. It + * is @b not safe to mount multiple images from the same WIM file read-write at + * the same time. + * + * To unmount the image, call wimlib_unmount_image(). This may be done in a + * different process. */ extern int wimlib_mount_image(WIMStruct *wim, @@ -3861,64 +3892,38 @@ wimlib_split(WIMStruct *wim, * * Unmounts a WIM image that was mounted using wimlib_mount_image(). * - * The image to unmount is specified by the path to the mountpoint, not the - * original ::WIMStruct passed to wimlib_mount_image(), which should not be - * touched and also may have been allocated in a different process. - * - * To unmount the image, the process calling this function communicates with the - * process that is managing the mounted WIM image. This function blocks until it - * is known whether the unmount succeeded or failed. In the case of a - * read-write mounted WIM, the unmount is not considered to have succeeded until - * all changes have been saved to the underlying WIM file. + * When unmounting a read-write mounted image, the default behavior is to + * discard changes to the image. Use ::WIMLIB_UNMOUNT_FLAG_COMMIT to cause the + * WIM image to be committed. * * @param dir - * The directory that the WIM image was mounted on. + * The directory the WIM image was mounted on. * @param unmount_flags - * Bitwise OR of the flags ::WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY, - * ::WIMLIB_UNMOUNT_FLAG_COMMIT, ::WIMLIB_UNMOUNT_FLAG_REBUILD, and/or - * ::WIMLIB_UNMOUNT_FLAG_RECOMPRESS. None of these flags affect read-only - * mounts. + * Bitwise OR of flags prefixed with @p WIMLIB_UNMOUNT_FLAG. * - * @return 0 on success; nonzero on error. + * @return 0 on success; nonzero on error. The possible error codes include: * - * @retval ::WIMLIB_ERR_DELETE_STAGING_DIR - * The filesystem daemon was unable to remove the staging directory and the - * temporary files that it contains. - * @retval ::WIMLIB_ERR_FILESYSTEM_DAEMON_CRASHED - * The filesystem daemon appears to have terminated before sending an exit - * status. - * @retval ::WIMLIB_ERR_FORK - * Could not @c fork() the process. - * @retval ::WIMLIB_ERR_FUSERMOUNT - * The @b fusermount program could not be executed or exited with a failure - * status. + * @retval ::WIMLIB_ERR_NOT_A_MOUNTPOINT + * There is no WIM image mounted on the specified directory. + * @retval ::WIMLIB_ERR_MOUNTED_IMAGE_IS_BUSY + * The read-write mounted WIM image cannot be committed because there are + * file descriptors open to it, and ::WIMLIB_UNMOUNT_FLAG_FORCE was not + * specified. * @retval ::WIMLIB_ERR_MQUEUE - * Could not open a POSIX message queue to communicate with the filesystem - * daemon servicing the mounted filesystem, could not send a message - * through the queue, or could not receive a message through the queue. - * @retval ::WIMLIB_ERR_NOMEM - * Failed to allocate needed memory. - * @retval ::WIMLIB_ERR_OPEN - * The filesystem daemon could not open a temporary file for writing the - * new WIM. - * @retval ::WIMLIB_ERR_READ - * A read error occurred when the filesystem daemon tried to a file from - * the staging directory - * @retval ::WIMLIB_ERR_RENAME - * The filesystem daemon failed to rename the newly written WIM file to the - * original WIM file. + * Could not create a POSIX message queue. + * @retval ::WIMLIB_ERR_NOT_PERMITTED_TO_UNMOUNT + * The WIM image was mounted by a different user. * @retval ::WIMLIB_ERR_UNSUPPORTED * Mounting is not supported, either because the platform is Windows, or - * because the platform is UNIX-like and wimlib was compiled with @c + * because the platform is UNIX-like and wimlib was compiled using @c * --without-fuse. - * @retval ::WIMLIB_ERR_WRITE - * A write error occurred when the filesystem daemon was writing to the new - * WIM file, or the filesystem daemon was unable to flush changes that had - * been made to files in the staging directory. + * + * Note: you can also unmount the image by using the @c umount() system call, or + * by using the @c umount or @c fusermount programs. However, you need to call + * this function if you want changes to be committed. */ extern int -wimlib_unmount_image(const wimlib_tchar *dir, - int unmount_flags); +wimlib_unmount_image(const wimlib_tchar *dir, int unmount_flags); /** * @ingroup G_mounting_wim_images diff --git a/include/wimlib/inode.h b/include/wimlib/inode.h index 8c6aa95f..84b49590 100644 --- a/include/wimlib/inode.h +++ b/include/wimlib/inode.h @@ -177,10 +177,17 @@ struct wim_inode { }; #ifdef WITH_FUSE - /* Used only during image mount: Table of file descriptors that - * have been opened to this inode. The table is automatically - * freed when the last file descriptor is closed. */ - struct wimfs_fd **i_fds; + struct { + /* Used only during image mount: Table of file + * descriptors that have been opened to this inode. + * This table is freed when the last file descriptor is + * closed. */ + struct wimfs_fd **i_fds; + + /* Lower bound on the index of the next available entry + * in 'i_fds'. */ + u16 i_next_fd; + }; #endif }; @@ -316,8 +323,7 @@ free_inode(struct wim_inode *inode); dentry_full_path(inode_first_dentry(inode)) extern struct wim_ads_entry * -inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name, - u16 *idx_ret); +inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name); extern struct wim_ads_entry * inode_add_ads_utf16le(struct wim_inode *inode, @@ -327,7 +333,7 @@ inode_add_ads_utf16le(struct wim_inode *inode, extern struct wim_ads_entry * inode_add_ads(struct wim_inode *dentry, const tchar *stream_name); -extern int +extern struct wim_ads_entry * inode_add_ads_with_data(struct wim_inode *inode, const tchar *name, const void *value, size_t size, struct wim_lookup_table *lookup_table); @@ -340,7 +346,7 @@ inode_set_unnamed_stream(struct wim_inode *inode, const void *data, size_t len, struct wim_lookup_table *lookup_table); extern void -inode_remove_ads(struct wim_inode *inode, u16 idx, +inode_remove_ads(struct wim_inode *inode, struct wim_ads_entry *entry, struct wim_lookup_table *lookup_table); static inline bool @@ -481,6 +487,15 @@ inode_stream_name_nbytes(const struct wim_inode *inode, unsigned stream_idx) return inode->i_ads_entries[stream_idx - 1].stream_name_nbytes; } +static inline u32 +inode_stream_idx_to_id(const struct wim_inode *inode, unsigned stream_idx) +{ + if (stream_idx == 0) + return 0; + else + return inode->i_ads_entries[stream_idx - 1].stream_id; +} + extern struct wim_lookup_table_entry * inode_unnamed_stream_resolved(const struct wim_inode *inode, u16 *stream_idx_ret); diff --git a/include/wimlib/lookup_table.h b/include/wimlib/lookup_table.h index 216565e1..f26a6573 100644 --- a/include/wimlib/lookup_table.h +++ b/include/wimlib/lookup_table.h @@ -169,7 +169,10 @@ struct wim_lookup_table_entry { tchar *file_on_disk; void *attached_buffer; #ifdef WITH_FUSE - tchar *staging_file_name; + struct { + char *staging_file_name; + int staging_dir_fd; + }; #endif #ifdef WITH_NTFS_3G struct ntfs_location *ntfs_loc; diff --git a/include/wimlib/wim.h b/include/wimlib/wim.h index 86926d89..c78fe905 100644 --- a/include/wimlib/wim.h +++ b/include/wimlib/wim.h @@ -66,7 +66,8 @@ struct WIMStruct { * generates WIMs with invalid reference counts.) */ u8 refcnts_ok : 1; - u8 wim_locked : 1; + /* Has the underlying WIM file been locked for appending? */ + u8 locked_for_append : 1; /* One of WIMLIB_COMPRESSION_TYPE_*, cached from the header flags. */ u8 compression_type; diff --git a/include/wimlib/write.h b/include/wimlib/write.h index 68ada298..c15e6ced 100644 --- a/include/wimlib/write.h +++ b/include/wimlib/write.h @@ -32,10 +32,17 @@ #if defined(HAVE_SYS_FILE_H) && defined(HAVE_FLOCK) extern int -lock_wim(WIMStruct *wim, int fd); +lock_wim_for_append(WIMStruct *wim, int fd); +extern void +unlock_wim_for_append(WIMStruct *wim, int fd); #else static inline int -lock_wim(WIMStruct *wim, int fd) +lock_wim_for_append(WIMStruct *wim, int fd) +{ + return 0; +} +static inline void +unlock_wim_for_append(WIMStruct *wim, int fd) { return 0; } diff --git a/programs/imagex.c b/programs/imagex.c index 6351475f..233e1f82 100644 --- a/programs/imagex.c +++ b/programs/imagex.c @@ -365,6 +365,7 @@ static const struct option unmount_options[] = { {T("check"), no_argument, NULL, IMAGEX_CHECK_OPTION}, {T("rebuild"), no_argument, NULL, IMAGEX_REBUILD_OPTION}, {T("lazy"), no_argument, NULL, IMAGEX_LAZY_OPTION}, + {T("force"), no_argument, NULL, IMAGEX_FORCE_OPTION}, {T("new-image"), no_argument, NULL, IMAGEX_NEW_IMAGE_OPTION}, {NULL, 0, NULL, 0}, }; @@ -1216,6 +1217,20 @@ imagex_progress_func(enum wimlib_progress_msg msg, imagex_printf(T("\nExtracting \"%"TS"\" as normal file (not WIMBoot pointer)\n"), info->wimboot_exclude.path_in_wim); break; + case WIMLIB_PROGRESS_MSG_UNMOUNT_BEGIN: + if (info->unmount.mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { + if (info->unmount.unmount_flags & WIMLIB_UNMOUNT_FLAG_COMMIT) { + imagex_printf(T("Committing changes to %"TS" (image %d)\n"), + info->unmount.mounted_wim, + info->unmount.mounted_image); + } else { + imagex_printf(T("Discarding changes to %"TS" (image %d)\n"), + info->unmount.mounted_wim, + info->unmount.mounted_image); + imagex_printf(T("\t(Use --commit to keep changes.)\n")); + } + } + break; default: break; } @@ -3673,7 +3688,14 @@ imagex_unmount(int argc, tchar **argv, int cmd) unmount_flags |= WIMLIB_UNMOUNT_FLAG_REBUILD; break; case IMAGEX_LAZY_OPTION: - unmount_flags |= WIMLIB_UNMOUNT_FLAG_LAZY; + case IMAGEX_FORCE_OPTION: + /* Now, unmount is lazy by default. However, committing + * the image will fail with + * WIMLIB_ERR_MOUNTED_IMAGE_IS_BUSY if there are open + * file descriptors on the WIM image. The + * WIMLIB_UNMOUNT_FLAG_FORCE option forces these file + * descriptors to be closed. */ + unmount_flags |= WIMLIB_UNMOUNT_FLAG_FORCE; break; case IMAGEX_NEW_IMAGE_OPTION: unmount_flags |= WIMLIB_UNMOUNT_FLAG_NEW_IMAGE; @@ -3693,13 +3715,19 @@ imagex_unmount(int argc, tchar **argv, int cmd) "without --commit also specified!")); goto out_err; } - imagex_printf(T("Committing changes as new image...\n")); } ret = wimlib_unmount_image_with_progress(argv[0], unmount_flags, imagex_progress_func, NULL); - if (ret) + if (ret) { imagex_error(T("Failed to unmount \"%"TS"\""), argv[0]); + if (ret == WIMLIB_ERR_MOUNTED_IMAGE_IS_BUSY) { + imagex_printf(T( + "\tNote: Use --commit --force to force changes " + "to be committed, regardless\n" + "\t of open files.\n")); + } + } out: return ret; @@ -4049,8 +4077,8 @@ T( #if WIM_MOUNTING_SUPPORTED [CMD_UNMOUNT] = T( -" %"TS" DIRECTORY [--commit] [--check] [--rebuild] [--lazy]\n" -" [--new-image]\n" +" %"TS" DIRECTORY [--commit] [--force] [--new-image]\n" +" [--check] [--rebuild]\n" ), #endif [CMD_UPDATE] = diff --git a/src/dentry.c b/src/dentry.c index 2dcc6167..763198d1 100644 --- a/src/dentry.c +++ b/src/dentry.c @@ -840,15 +840,13 @@ wim_pathname_to_stream(WIMStruct *wim, if (stream_name) { struct wim_ads_entry *ads_entry; - u16 ads_idx; - ads_entry = inode_get_ads_entry(inode, stream_name, - &ads_idx); - if (ads_entry) { - stream_idx = ads_idx + 1; - lte = ads_entry->lte; - } else { - return -ENOENT; - } + + ads_entry = inode_get_ads_entry(inode, stream_name); + if (!ads_entry) + return -errno; + + stream_idx = ads_entry - inode->i_ads_entries + 1; + lte = ads_entry->lte; } else { lte = inode_unnamed_stream_resolved(inode, &stream_idx); } diff --git a/src/inode.c b/src/inode.c index 57d92fb2..ae971d83 100644 --- a/src/inode.c +++ b/src/inode.c @@ -39,6 +39,8 @@ #include "wimlib/security.h" #include "wimlib/timestamp.h" +#include + /* Allocate a new inode. Set the timestamps to the current time. */ struct wim_inode * new_inode(void) @@ -138,10 +140,11 @@ ads_entry_has_name(const struct wim_ads_entry *entry, * * If @p stream_name is the empty string, NULL is returned --- that is, this * function will not return "unnamed" alternate data stream entries. + * + * If NULL is returned, errno is set. */ struct wim_ads_entry * -inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name, - u16 *idx_ret) +inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name) { int ret; const utf16lechar *stream_name_utf16le; @@ -149,11 +152,15 @@ inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name, u16 i; struct wim_ads_entry *result; - if (inode->i_num_ads == 0) + if (inode->i_num_ads == 0) { + errno = ENOENT; return NULL; + } - if (stream_name[0] == T('\0')) + if (stream_name[0] == T('\0')) { + errno = ENOENT; return NULL; + } ret = tstr_get_utf16le_and_len(stream_name, &stream_name_utf16le, &stream_name_utf16le_nbytes); @@ -168,8 +175,6 @@ inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name, stream_name_utf16le_nbytes, default_ignore_case)) { - if (idx_ret) - *idx_ret = i; result = &inode->i_ads_entries[i]; break; } @@ -177,6 +182,8 @@ inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name, tstr_put_utf16le(stream_name_utf16le); + if (!result) + errno = ENOENT; return result; } @@ -190,6 +197,7 @@ do_inode_add_ads(struct wim_inode *inode, if (inode->i_num_ads >= 0xfffe) { ERROR("Too many alternate data streams in one inode!"); + errno = EFBIG; return NULL; } num_ads = inode->i_num_ads + 1; @@ -232,24 +240,21 @@ inode_add_ads_utf16le(struct wim_inode *inode, /* * Add an alternate stream entry to a WIM inode. On success, returns a pointer - * to the new entry; on failure, returns NULL. + * to the new entry; on failure, returns NULL and sets errno. */ struct wim_ads_entry * inode_add_ads(struct wim_inode *inode, const tchar *stream_name) { utf16lechar *stream_name_utf16le = NULL; size_t stream_name_utf16le_nbytes = 0; - int ret; struct wim_ads_entry *result; - if (stream_name && *stream_name) { - ret = tstr_to_utf16le(stream_name, - tstrlen(stream_name) * sizeof(tchar), - &stream_name_utf16le, - &stream_name_utf16le_nbytes); - if (ret) + if (stream_name && *stream_name) + if (tstr_to_utf16le(stream_name, + tstrlen(stream_name) * sizeof(tchar), + &stream_name_utf16le, + &stream_name_utf16le_nbytes)) return NULL; - } result = do_inode_add_ads(inode, stream_name_utf16le, stream_name_utf16le_nbytes); @@ -258,27 +263,25 @@ inode_add_ads(struct wim_inode *inode, const tchar *stream_name) return result; } -int +struct wim_ads_entry * inode_add_ads_with_data(struct wim_inode *inode, const tchar *name, const void *value, size_t size, struct wim_lookup_table *lookup_table) { - struct wim_ads_entry *new_ads_entry; + struct wim_ads_entry *new_entry; wimlib_assert(inode->i_resolved); - new_ads_entry = inode_add_ads(inode, name); - if (new_ads_entry == NULL) - return WIMLIB_ERR_NOMEM; + new_entry = inode_add_ads(inode, name); + if (!new_entry) + return NULL; - new_ads_entry->lte = new_stream_from_data_buffer(value, size, - lookup_table); - if (new_ads_entry->lte == NULL) { - inode_remove_ads(inode, new_ads_entry - inode->i_ads_entries, - lookup_table); - return WIMLIB_ERR_NOMEM; + new_entry->lte = new_stream_from_data_buffer(value, size, lookup_table); + if (!new_entry->lte) { + inode_remove_ads(inode, new_entry, lookup_table); + return NULL; } - return 0; + return new_entry; } bool @@ -305,22 +308,20 @@ inode_set_unnamed_stream(struct wim_inode *inode, const void *data, size_t len, /* Remove an alternate data stream from a WIM inode */ void -inode_remove_ads(struct wim_inode *inode, u16 idx, +inode_remove_ads(struct wim_inode *inode, struct wim_ads_entry *entry, struct wim_lookup_table *lookup_table) { - struct wim_ads_entry *ads_entry; struct wim_lookup_table_entry *lte; + unsigned idx = entry - inode->i_ads_entries; wimlib_assert(idx < inode->i_num_ads); wimlib_assert(inode->i_resolved); - ads_entry = &inode->i_ads_entries[idx]; - - lte = ads_entry->lte; + lte = entry->lte; if (lte) lte_decrement_refcnt(lte, lookup_table); - destroy_ads_entry(ads_entry); + destroy_ads_entry(entry); memmove(&inode->i_ads_entries[idx], &inode->i_ads_entries[idx + 1], diff --git a/src/lookup_table.c b/src/lookup_table.c index 1950ab21..0e4f96a3 100644 --- a/src/lookup_table.c +++ b/src/lookup_table.c @@ -269,7 +269,8 @@ lte_decrement_refcnt(struct wim_lookup_table_entry *lte, * that there still may be open file descriptors to it.) * */ if (lte->resource_location == RESOURCE_IN_STAGING_FILE) - unlink(lte->staging_file_name); + unlinkat(lte->staging_dir_fd, + lte->staging_file_name, 0); #endif } else { if (!should_retain_lte(lte)) diff --git a/src/mount_image.c b/src/mount_image.c index 168ee852..86cc8153 100644 --- a/src/mount_image.c +++ b/src/mount_image.c @@ -31,129 +31,164 @@ #endif #include "wimlib.h" -#include "wimlib/error.h" #ifdef WITH_FUSE #ifdef __WIN32__ -# error "FUSE mount not supported on Win32! Please configure --without-fuse" +# error "FUSE mount not supported on Windows! Please configure --without-fuse" #endif -#include "wimlib/encoding.h" -#include "wimlib/file_io.h" #include "wimlib/dentry.h" -#include "wimlib/inode.h" -#include "wimlib/lookup_table.h" +#include "wimlib/encoding.h" #include "wimlib/metadata.h" #include "wimlib/paths.h" #include "wimlib/progress.h" #include "wimlib/reparse.h" -#include "wimlib/resource.h" #include "wimlib/timestamp.h" #include "wimlib/unix_data.h" -#include "wimlib/version.h" #include "wimlib/write.h" #include "wimlib/xml.h" +#include #include -#include #include #include -#include +#include #include #include #include #include #include -#include #include #include #define FUSE_USE_VERSION 26 #include - -#ifdef ENABLE_XATTR #include + +#ifndef O_NOFOLLOW +# define O_NOFOLLOW 0 /* Security only... */ #endif -#define MSG_VERSION_TOO_HIGH -1 -#define MSG_BREAK_LOOP -2 +#define WIMFS_MQUEUE_NAME_LEN 32 + +#define WIMLIB_UNMOUNT_FLAG_SEND_PROGRESS 0x80000000 + +struct wimfs_unmount_info { + unsigned unmount_flags; + char mq_name[WIMFS_MQUEUE_NAME_LEN + 1]; +}; + +struct commit_progress_report { + enum wimlib_progress_msg msg; + union wimlib_progress_info info; +}; -/* File descriptor to a file open on the WIM filesystem. */ +/* Description of an open file on a mounted WIM image. Actually, this + * represents the open state of a particular data stream of an inode, rather + * than the inode itself. (An inode might have multiple named data streams in + * addition to the default, unnamed data stream.) At a given time, an inode in + * the WIM image might have multiple file descriptors open to it, each to any + * one of its data streams. */ struct wimfs_fd { + + /* Pointer to the inode of this open file. + * 'i_num_opened_fds' of the inode tracks the number of file descriptors + * that reference it. */ struct wim_inode *f_inode; + + /* Pointer to the lookup table entry for the data stream that has been + * opened. 'num_opened_fds' of the lookup table entry tracks the number + * of file descriptors that reference it. Or, this value may be NULL, + * which indicates that the opened stream is empty and consequently does + * not have a lookup table entry. */ struct wim_lookup_table_entry *f_lte; - struct filedes staging_fd; - u16 idx; - u32 stream_id; + + /* If valid (filedes_valid(&f_staging_fd)), this contains the + * corresponding native file descriptor for the staging file that has + * been created for reading from and/or writing to this open stream. A + * single staging file might have multiple file descriptors open to it + * simultaneously, each used by a different 'struct wimfs_fd'. + * + * Or, if invalid (!filedes_valid(&f_staging_fd)), this 'struct + * wimfs_fd' is not associated with a staging file. This is permissible + * only if this 'struct wimfs_fd' was opened read-only and the stream + * has not yet been extracted to a staging file. */ + struct filedes f_staging_fd; + + /* 0-based index of this file descriptor in the file descriptor table of + * its inode. */ + u16 f_idx; + + /* Unique ID of the opened stream in the inode. This will stay the same + * even if the indices of the inode's alternate data streams are changed + * by a deletion. */ + u32 f_stream_id; }; +#define WIMFS_FD(fi) ((struct wimfs_fd *)(uintptr_t)((fi)->fh)) + +/* Context structure for a mounted WIM image. */ struct wimfs_context { - /* The WIMStruct for the mounted WIM. */ + /* The WIMStruct containing the mounted image. The mounted image is the + * currently selected image (wim->current_image). */ WIMStruct *wim; - /* Name of the staging directory for a read-write mount. Whenever a new file is - * created, it is done so in the staging directory. Furthermore, whenever a - * file in the WIM is modified, it is extracted to the staging directory. If - * changes are commited when the WIM is unmounted, the file resources are merged - * in from the staging directory when writing the new WIM. */ - char *staging_dir_name; - size_t staging_dir_name_len; - - /* Flags passed to wimlib_mount(). */ + /* Flags passed to wimlib_mount_image() (WIMLIB_MOUNT_FLAG_*). */ int mount_flags; - /* Default flags to use when looking up a WIM dentry (depends on whether - * the Windows interface to alternate data streams is being used or - * not). */ + /* Default flags for path lookup in the WIM image. */ int default_lookup_flags; - /* Next inode number to be assigned. Note: I didn't bother with a - * bitmap of free inode numbers since this isn't even a "real" - * filesystem anyway. */ - u64 next_ino; - - /* List of inodes in the mounted image */ - struct list_head *image_inode_list; + /* Information about the user who has mounted the WIM image */ + uid_t owner_uid; + gid_t owner_gid; - /* Original list of streams in the mounted image, linked by - * mount_orig_stream_list. */ - struct list_head orig_stream_list; + /* Information about the staging directory for a read-write mount. */ + int parent_dir_fd; + int staging_dir_fd; + char *staging_dir_name; - /* Name and message queue descriptors for message queues between the - * filesystem daemon process and the unmount process. These are used - * when the filesystem is unmounted and the process running - * wimlib_unmount_image() needs to communicate with the filesystem - * daemon running fuse_main() (i.e. the process created by a call to - * wimlib_mount_image(). */ - char *unmount_to_daemon_mq_name; - char *daemon_to_unmount_mq_name; - mqd_t unmount_to_daemon_mq; - mqd_t daemon_to_unmount_mq; + /* For read-write mounts, the inode number to be assigned to the next + * created file. Note: since this isn't a persistent filesystem and we + * can re-assign the inode numbers just before mounting the image, it's + * good enough to just generate inode numbers sequentially. */ + u64 next_ino; - uid_t default_uid; - gid_t default_gid; + /* Number of file descriptors open to the mounted WIM image. */ + unsigned long num_open_fds; - int status; - bool have_status; + /* Original list of single-instance streams in the mounted image, linked + * by 'struct wim_lookup_table_entry'.orig_stream_list. */ + struct list_head orig_stream_list; }; -static void -init_wimfs_context(struct wimfs_context *ctx) -{ - memset(ctx, 0, sizeof(*ctx)); - ctx->unmount_to_daemon_mq = (mqd_t)-1; - ctx->daemon_to_unmount_mq = (mqd_t)-1; -} - #define WIMFS_CTX(fuse_ctx) ((struct wimfs_context*)(fuse_ctx)->private_data) +/* Retrieve the context structure for the currently mounted WIM image. + * + * Note: this is a per-thread variable. It is possible for different threads to + * mount different images at the same time in the same process, although they + * must use different WIMStructs! */ static inline struct wimfs_context * wimfs_get_context(void) { return WIMFS_CTX(fuse_get_context()); } +static void +wimfs_inc_num_open_fds(void) +{ + wimfs_get_context()->num_open_fds++; +} + +static void +wimfs_dec_num_open_fds(void) +{ + wimfs_get_context()->num_open_fds--; +} + +/* Retrieve the WIMStruct for the currently mounted WIM image. */ static inline WIMStruct * wimfs_get_WIMStruct(void) { @@ -166,23 +201,37 @@ get_lookup_flags(const struct wimfs_context *ctx) return ctx->default_lookup_flags; } -/* Returns nonzero if write permission is requested on the file open flags */ -static inline int +/* Is write permission requested on the file? */ +static inline bool flags_writable(int open_flags) { int accmode = (open_flags & O_ACCMODE); return (accmode == O_RDWR || accmode == O_WRONLY); } +static mode_t +fuse_mask_mode(mode_t mode, const struct fuse_context *fuse_ctx) +{ +#if FUSE_MAJOR_VERSION > 2 || (FUSE_MAJOR_VERSION == 2 && FUSE_MINOR_VERSION >= 8) + mode &= ~fuse_ctx->umask; +#endif + return mode; +} + /* - * Allocate a file descriptor for a stream. + * Allocate a file descriptor to a data stream in the mounted WIM image. * - * @inode: inode containing the stream we're opening - * @stream_id: ID of the stream we're opening - * @lte: Lookup table entry for the stream (may be NULL) - * @fd_ret: Return the allocated file descriptor if successful. + * @inode + * A pointer to the inode containing the stream being opened. + * @stream_id + * The ID of the data stream being opened within the inode. + * @lte + * A pointer to the lookup table entry for the stream data. Or, for a + * 0-byte stream, this may be NULL. + * @fd_ret + * On success, a pointer to the new file descriptor will be stored here. * - * Return 0 iff successful or negative error code if unsuccessful. + * Returns 0 or a -errno code. */ static int alloc_wimfs_fd(struct wim_inode *inode, @@ -190,27 +239,29 @@ alloc_wimfs_fd(struct wim_inode *inode, struct wim_lookup_table_entry *lte, struct wimfs_fd **fd_ret) { - static const u16 fds_per_alloc = 8; + static const u16 min_fds_per_alloc = 8; static const u16 max_fds = 0xffff; - - DEBUG("Allocating fd for stream ID %u from inode %#"PRIx64" " - "(open = %u, allocated = %u)", - stream_id, inode->i_ino, inode->i_num_opened_fds, - inode->i_num_allocated_fds); + u16 i; + struct wimfs_fd *fd; if (inode->i_num_opened_fds == inode->i_num_allocated_fds) { - struct wimfs_fd **fds; u16 num_new_fds; + struct wimfs_fd **fds; - if (inode->i_num_allocated_fds == max_fds) - return -EMFILE; + /* Expand this inode's file descriptor table. */ + + num_new_fds = max(min_fds_per_alloc, + inode->i_num_allocated_fds / 4); - num_new_fds = min(fds_per_alloc, + num_new_fds = min(num_new_fds, max_fds - inode->i_num_allocated_fds); + if (num_new_fds == 0) + return -EMFILE; + fds = REALLOC(inode->i_fds, (inode->i_num_allocated_fds + num_new_fds) * - sizeof(inode->i_fds[0])); + sizeof(fds[0])); if (!fds) return -ENOMEM; @@ -218,111 +269,127 @@ alloc_wimfs_fd(struct wim_inode *inode, num_new_fds * sizeof(fds[0])); inode->i_fds = fds; inode->i_num_allocated_fds += num_new_fds; + inode->i_next_fd = inode->i_num_opened_fds; } - for (u16 i = 0; ; i++) { - if (!inode->i_fds[i]) { - struct wimfs_fd *fd = CALLOC(1, sizeof(*fd)); - if (!fd) - return -ENOMEM; - - fd->f_inode = inode; - fd->f_lte = lte; - filedes_invalidate(&fd->staging_fd); - fd->idx = i; - fd->stream_id = stream_id; - *fd_ret = fd; - inode->i_fds[i] = fd; - inode->i_num_opened_fds++; - if (lte) - lte->num_opened_fds++; - DEBUG("Allocated fd (idx = %u)", fd->idx); - return 0; - } - } + + /* Allocate the file descriptor in the first available space in the + * inode's file descriptor table. + * + * i_next_fd is the lower bound on the next open slot. */ + for (i = inode->i_next_fd; inode->i_fds[i]; i++) + ; + + fd = MALLOC(sizeof(*fd)); + if (!fd) + return -ENOMEM; + + fd->f_inode = inode; + fd->f_lte = lte; + filedes_invalidate(&fd->f_staging_fd); + fd->f_idx = i; + fd->f_stream_id = stream_id; + *fd_ret = fd; + inode->i_fds[i] = fd; + inode->i_num_opened_fds++; + if (lte) + lte->num_opened_fds++; + wimfs_inc_num_open_fds(); + inode->i_next_fd = i + 1; + return 0; } -static void -inode_put_fd(struct wim_inode *inode, struct wimfs_fd *fd) +/* + * Close a file descriptor to a data stream in the mounted WIM image. + * + * Returns 0 or a -errno code. The file descriptor is always closed. + */ +static int +close_wimfs_fd(struct wimfs_fd *fd) { - wimlib_assert(inode != NULL); - wimlib_assert(fd->f_inode == inode); - wimlib_assert(inode->i_num_opened_fds != 0); - wimlib_assert(fd->idx < inode->i_num_allocated_fds); - wimlib_assert(inode->i_fds[fd->idx] == fd); + int ret = 0; + struct wim_inode *inode; + + /* Close the staging file if open. */ + if (filedes_valid(&fd->f_staging_fd)) + if (filedes_close(&fd->f_staging_fd)) + ret = -errno; + + /* Release this file descriptor from its lookup table entry. */ + if (fd->f_lte) + lte_decrement_num_opened_fds(fd->f_lte); + + wimfs_dec_num_open_fds(); - inode->i_fds[fd->idx] = NULL; + /* Release this file descriptor from its inode. */ + inode = fd->f_inode; + inode->i_fds[fd->f_idx] = NULL; + if (fd->f_idx < inode->i_next_fd) + inode->i_next_fd = fd->f_idx; FREE(fd); if (--inode->i_num_opened_fds == 0) { + /* The last file descriptor to this inode was closed. */ FREE(inode->i_fds); inode->i_fds = NULL; inode->i_num_allocated_fds = 0; if (inode->i_nlink == 0) + /* No links to this inode remain. Get rid of it. */ free_inode(inode); } + return ret; } -static int -lte_put_fd(struct wim_lookup_table_entry *lte, struct wimfs_fd *fd) -{ - wimlib_assert(fd->f_lte == lte); - - if (!lte) /* Empty stream with no lookup table entry */ - return 0; - - /* Close staging file descriptor if needed. */ - - if (lte->resource_location == RESOURCE_IN_STAGING_FILE - && filedes_valid(&fd->staging_fd)) - { - if (filedes_close(&fd->staging_fd)) { - ERROR_WITH_ERRNO("Failed to close staging file"); - return -errno; - } - } - lte_decrement_num_opened_fds(lte); - return 0; -} - -/* Close a file descriptor. */ -static int -close_wimfs_fd(struct wimfs_fd *fd) +/* + * Translate a path into the corresponding inode in the mounted WIM image. + * + * See get_dentry() for more information. + * + * Returns a pointer to the resulting inode, or NULL with errno set. + */ +static struct wim_inode * +wim_pathname_to_inode(WIMStruct *wim, const char *path) { - int ret; - DEBUG("Closing fd (ino = %#"PRIx64", opened = %u, allocated = %u)", - fd->f_inode->i_ino, fd->f_inode->i_num_opened_fds, - fd->f_inode->i_num_allocated_fds); - ret = lte_put_fd(fd->f_lte, fd); - if (ret) - return ret; - - inode_put_fd(fd->f_inode, fd); - return 0; -} + struct wim_dentry *dentry; -static mode_t -fuse_mask_mode(mode_t mode, struct fuse_context *fuse_ctx) -{ -#if FUSE_MAJOR_VERSION > 2 || (FUSE_MAJOR_VERSION == 2 && FUSE_MINOR_VERSION >= 8) - mode &= ~fuse_ctx->umask; -#endif - return mode; + dentry = get_dentry(wim, path, WIMLIB_CASE_SENSITIVE); + if (!dentry) + return NULL; + return dentry->d_inode; } /* - * Add a new dentry with a new inode to a WIM image. + * Create a new file in the mounted WIM image. * - * Returns 0 on success, or negative error number on failure. + * @fuse_ctx + * The FUSE context for the mounted image. + * @path + * The path at which to create the first link to the new file. If a file + * already exists at this path, -EEXIST is returned. + * @mode + * The UNIX mode for the new file. This is only honored if + * WIMLIB_MOUNT_FLAG_UNIX_DATA was passed to wimlib_mount_image(). + * @rdev + * The device ID for the new file, encoding the major and minor device + * numbers. This is only honored if WIMLIB_MOUNT_FLAG_UNIX_DATA was passed + * to wimlib_mount_image(). + * @attributes + * Windows file attributes to use for the new file. + * @dentry_ret + * On success, a pointer to the new dentry is returned here. Its d_inode + * member will point to the new inode that was created for it and added to + * the mounted WIM image. + * + * Returns 0 or a -errno code. */ static int create_dentry(struct fuse_context *fuse_ctx, const char *path, - mode_t mode, dev_t rdev, int attributes, + mode_t mode, dev_t rdev, u32 attributes, struct wim_dentry **dentry_ret) { + struct wimfs_context *wimfs_ctx = WIMFS_CTX(fuse_ctx); struct wim_dentry *parent; - struct wim_dentry *new; const char *basename; - struct wimfs_context *wimfs_ctx = WIMFS_CTX(fuse_ctx); - int ret; + struct wim_dentry *new_dentry; + struct wim_inode *new_inode; parent = get_parent_dentry(wimfs_ctx->wim, path, WIMLIB_CASE_SENSITIVE); if (!parent) @@ -332,16 +399,18 @@ create_dentry(struct fuse_context *fuse_ctx, const char *path, return -ENOTDIR; basename = path_basename(path); + if (get_dentry_child_with_name(parent, basename, WIMLIB_CASE_SENSITIVE)) return -EEXIST; - ret = new_dentry_with_inode(basename, &new); - if (ret) + if (new_dentry_with_inode(basename, &new_dentry)) return -ENOMEM; - new->d_inode->i_resolved = 1; - new->d_inode->i_ino = wimfs_ctx->next_ino++; - new->d_inode->i_attributes = attributes; + new_inode = new_dentry->d_inode; + + new_inode->i_resolved = 1; + new_inode->i_ino = wimfs_ctx->next_ino++; + new_inode->i_attributes = attributes; if (wimfs_ctx->mount_flags & WIMLIB_MOUNT_FLAG_UNIX_DATA) { struct wimlib_unix_data unix_data; @@ -350,50 +419,44 @@ create_dentry(struct fuse_context *fuse_ctx, const char *path, unix_data.gid = fuse_ctx->gid; unix_data.mode = fuse_mask_mode(mode, fuse_ctx); unix_data.rdev = rdev; - - if (!inode_set_unix_data(new->d_inode, &unix_data, - UNIX_DATA_ALL)) + if (!inode_set_unix_data(new_inode, &unix_data, UNIX_DATA_ALL)) { - free_dentry(new); + free_dentry(new_dentry); return -ENOMEM; } } - dentry_add_child(parent, new); - list_add_tail(&new->d_inode->i_list, wimfs_ctx->image_inode_list); + + list_add_tail(&new_inode->i_list, + &wim_get_current_image_metadata(wimfs_ctx->wim)->inode_list); + + dentry_add_child(parent, new_dentry); + if (dentry_ret) - *dentry_ret = new; + *dentry_ret = new_dentry; return 0; } -static struct wim_inode * -wim_pathname_to_inode(WIMStruct *wim, const tchar *path) -{ - struct wim_dentry *dentry; - dentry = get_dentry(wim, path, WIMLIB_CASE_SENSITIVE); - if (dentry) - return dentry->d_inode; - else - return NULL; -} - /* - * Remove a dentry from a mounted WIM image; i.e. remove an alias for an inode. + * Remove a dentry from the mounted WIM image; i.e. remove an alias for an + * inode. */ static void remove_dentry(struct wim_dentry *dentry, struct wim_lookup_table *lookup_table) { - /* Put a reference to each stream the inode contains. */ + /* Drop the reference to each stream the inode contains. */ inode_unref_streams(dentry->d_inode, lookup_table); /* Unlink the dentry from the image's dentry tree. */ unlink_dentry(dentry); /* Delete the dentry. This will also decrement the link count of the - * corresponding inode. */ + * corresponding inode, and possibly cause it to be deleted as well. */ free_dentry(dentry); } +/* Generate UNIX filetype mode bits for the specified WIM inode, based on its + * Windows file attributes. */ static mode_t inode_unix_file_type(const struct wim_inode *inode) { @@ -405,17 +468,22 @@ inode_unix_file_type(const struct wim_inode *inode) return S_IFREG; } +/* Generate a default UNIX mode for the specified WIM inode. */ static mode_t inode_default_unix_mode(const struct wim_inode *inode) { return inode_unix_file_type(inode) | 0777; } -/* Transfers file attributes from a struct wim_inode to a `stat' buffer. +/* + * Retrieve standard UNIX metadata ('struct stat') for a WIM inode. * - * The lookup table entry tells us which stream in the inode we are statting. - * For a named data stream, everything returned is the same as the unnamed data - * stream except possibly the size and block count. */ + * @lte specifies the stream of the inode that is being queried. We mostly + * return the same information for all streams, but st_size and st_blocks may be + * different for different streams. + * + * This always returns 0. + */ static int inode_to_stbuf(const struct wim_inode *inode, const struct wim_lookup_table_entry *lte, @@ -428,22 +496,25 @@ inode_to_stbuf(const struct wim_inode *inode, if ((ctx->mount_flags & WIMLIB_MOUNT_FLAG_UNIX_DATA) && inode_get_unix_data(inode, &unix_data)) { + /* Use the user ID, group ID, mode, and device ID from the + * inode's extra UNIX metadata information. */ stbuf->st_uid = unix_data.uid; stbuf->st_gid = unix_data.gid; stbuf->st_mode = unix_data.mode; stbuf->st_rdev = unix_data.rdev; } else { - stbuf->st_uid = ctx->default_uid; - stbuf->st_gid = ctx->default_gid; + /* Generate default values for the user ID, group ID, and mode. + * + * Note: in the case of an allow_other mount, fuse_context.uid + * may not be the same as wimfs_context.owner_uid! */ + stbuf->st_uid = ctx->owner_uid; + stbuf->st_gid = ctx->owner_gid; stbuf->st_mode = inode_default_unix_mode(inode); - stbuf->st_rdev = 0; } - stbuf->st_ino = (ino_t)inode->i_ino; + stbuf->st_ino = inode->i_ino; stbuf->st_nlink = inode->i_nlink; if (lte) stbuf->st_size = lte->size; - else - stbuf->st_size = 0; #ifdef HAVE_STAT_NANOSECOND_PRECISION stbuf->st_atim = wim_timestamp_to_timespec(inode->i_last_access_time); stbuf->st_mtim = wim_timestamp_to_timespec(inode->i_last_write_time); @@ -457,6 +528,7 @@ inode_to_stbuf(const struct wim_inode *inode, return 0; } +/* Update the last access and last write timestamps of a WIM inode. */ static void touch_inode(struct wim_inode *inode) { @@ -465,61 +537,37 @@ touch_inode(struct wim_inode *inode) inode->i_last_write_time = now; } -/* Creates a new staging file and returns its file descriptor opened for - * writing. - * - * @name_ret: A location into which the a pointer to the newly allocated name of - * the staging file is stored. +/* + * Create a new file in the staging directory for a read-write mounted image. * - * @ctx: Context for the WIM filesystem; this provides the name of the - * staging directory. + * On success, returns the file descriptor for the new staging file, opened for + * writing. In addition, stores the allocated name of the staging file in + * @name_ret. * - * On success, returns the file descriptor for the staging file, opened for - * writing. On failure, returns -1 and sets errno. + * On failure, returns -1 and sets errno. */ static int -create_staging_file(char **name_ret, struct wimfs_context *ctx) +create_staging_file(const struct wimfs_context *ctx, char **name_ret) { - size_t name_len; - char *name; - struct stat stbuf; - int fd; - int errno_save; static const size_t STAGING_FILE_NAME_LEN = 20; + char *name; + int fd; - name_len = ctx->staging_dir_name_len + 1 + STAGING_FILE_NAME_LEN; - name = MALLOC(name_len + 1); - if (!name) { - errno = ENOMEM; - return -1; - } - - do { - - memcpy(name, ctx->staging_dir_name, ctx->staging_dir_name_len); - name[ctx->staging_dir_name_len] = '/'; - randomize_char_array_with_alnum(name + ctx->staging_dir_name_len + 1, - STAGING_FILE_NAME_LEN); - name[name_len] = '\0'; - - - /* Just in case, verify that the randomly generated name doesn't name an - * existing file, and try again if so */ - } while (stat(name, &stbuf) == 0); - - if (errno != ENOENT) /* other error?! */ + name = MALLOC(STAGING_FILE_NAME_LEN + 1); + if (!name) return -1; - - /* doesn't exist--- ok */ - - DEBUG("Creating staging file `%s'", name); - - fd = open(name, O_WRONLY | O_CREAT | O_EXCL, 0600); - if (fd == -1) { - errno_save = errno; + name[STAGING_FILE_NAME_LEN] = '\0'; + +retry: + randomize_char_array_with_alnum(name, STAGING_FILE_NAME_LEN); + fd = openat(ctx->staging_dir_fd, name, + O_WRONLY | O_CREAT | O_EXCL | O_NOFOLLOW, 0600); + if (unlikely(fd < 0)) { + if (unlikely(errno == EEXIST)) + /* Try again with another name. */ + goto retry; FREE(name); - errno = errno_save; } else { *name_ret = name; } @@ -528,104 +576,105 @@ create_staging_file(char **name_ret, struct wimfs_context *ctx) /* * Extract a WIM resource to the staging directory. + * This is necessary if a stream using the resource is being opened for writing. * - * @inode: Inode that contains the stream we are extracting + * @inode + * The inode containing the stream being opened for writing. * - * @stream_id: Identifier for the stream (it stays constant even if the indices - * of the stream entries are changed) + * @stream_idx + * The index of the stream in @inode being opened for writing. * - * @lte: Pointer to pointer to the lookup table entry for the stream we need to - * extract, or NULL if there was no lookup table entry present for the stream + * @lte_ptr + * *lte_ptr is the lookup table entry for the stream being extracted, or + * NULL if the stream does not have a lookup table entry (which is possible + * if the stream is empty). On success, *lte_ptr will be set to point to a + * lookup table entry that represents the resource in its new location in a + * staging file. This may be the same as the old entry in the case that it + * was reused, or it may be a new entry. * - * @size: Number of bytes of the stream we want to extract (this supports the - * wimfs_truncate() function). It may be more than the actual stream length, in - * which case the extra space is filled with zeroes. + * @size + * Number of bytes of the stream to extract and include in the staging file + * resource. It may be less than the actual stream length, in which case + * only a prefix of the resource will be extracted. It may also be more + * than the actual stream length, in which case the extra space will be + * zero-filled. * - * @ctx: Context for the WIM filesystem. - * - * Returns 0 on success or a negative error code on failure. + * Returns 0 or a -errno code. */ static int extract_resource_to_staging_dir(struct wim_inode *inode, - u32 stream_id, - struct wim_lookup_table_entry **lte, + u16 stream_idx, + struct wim_lookup_table_entry **lte_ptr, off_t size, - struct wimfs_context *ctx) + const struct wimfs_context *ctx) { + struct wim_lookup_table_entry *old_lte; + struct wim_lookup_table_entry *new_lte; char *staging_file_name; - int ret; - int fd; - struct wim_lookup_table_entry *old_lte, *new_lte; + int staging_fd; off_t extract_size; + int result; + u32 stream_id; + int ret; - DEBUG("Extracting resource to staging dir: inode %"PRIu64", " - "stream id %"PRIu32, inode->i_ino, stream_id); - - old_lte = *lte; - - wimlib_assert(old_lte == NULL || - old_lte->resource_location != RESOURCE_IN_STAGING_FILE); + old_lte = *lte_ptr; - /* Create the staging file */ - fd = create_staging_file(&staging_file_name, ctx); - if (fd == -1) + /* Create the staging file. */ + staging_fd = create_staging_file(ctx, &staging_file_name); + if (unlikely(staging_fd < 0)) return -errno; - /* Extract the stream to the staging file (possibly truncated) */ + /* Extract the stream to the staging file (possibly truncated). */ if (old_lte) { - struct filedes wimlib_fd; - filedes_init(&wimlib_fd, fd); + struct filedes fd; + + filedes_init(&fd, staging_fd); + errno = 0; extract_size = min(old_lte->size, size); - ret = extract_stream_to_fd(old_lte, &wimlib_fd, extract_size); + result = extract_stream_to_fd(old_lte, &fd, extract_size); } else { - ret = 0; extract_size = 0; + result = 0; } /* In the case of truncate() to more than the file length, extend the - * file with zeroes by calling ftruncate() on the underlying staging - * file */ - if (ret == 0 && size > extract_size) - ret = ftruncate(fd, size); - - /* Close the staging file descriptor and check for errors. If there's - * an error, unlink the staging file. */ - if (ret != 0 || close(fd) != 0) { - if (errno != 0) - ret = -errno; - else - ret = -EIO; - close(fd); + * staging file with zeroes by calling ftruncate(). */ + if (!result && size > extract_size) + result = ftruncate(staging_fd, size); + + /* Close the staging file. */ + if (close(staging_fd)) + result = -1; + + /* If an error occurred, unlink the staging file. */ + if (unlikely(result)) { + /* extract_stream_to_fd() should set errno, but if it didn't, + * set a default value. */ + ret = errno ? -errno : -EIO; goto out_delete_staging_file; } /* Now deal with the lookup table entries. We may be able to re-use the - * existing entry, but we may have to create a new one instead. */ + * existing entry, but we may have to create a new one instead. */ + + stream_id = inode_stream_idx_to_id(inode, stream_idx); if (old_lte && inode->i_nlink == old_lte->refcnt) { /* The reference count of the existing lookup table entry is the * same as the link count of the inode that contains the stream - * we're opening. Therefore, ALL the references to the lookup + * we're opening. Therefore, all the references to the lookup * table entry correspond to the stream we're trying to extract, * so the lookup table entry can be re-used. */ - DEBUG("Re-using lookup table entry"); lookup_table_unlink(ctx->wim->lookup_table, old_lte); + lte_put_resource(old_lte); new_lte = old_lte; } else { - if (old_lte) { - /* There's an existing lookup table entry, but its - * reference count is greater than the link count for - * the inode containing a stream we're opening. - * Therefore, we need to split the lookup table entry. - */ - wimlib_assert(old_lte->refcnt > inode->i_nlink); - DEBUG("Splitting lookup table entry " - "(inode->i_nlink = %u, old_lte->refcnt = %u)", - inode->i_nlink, old_lte->refcnt); - } + /* We need to split the old lookup table entry because it also + * has other references. Or, there was no old lookup table + * entry, so we need to create a new one anyway. */ new_lte = new_lookup_table_entry(); - if (!new_lte) { + if (unlikely(!new_lte)) { ret = -ENOMEM; goto out_delete_staging_file; } @@ -640,568 +689,268 @@ extract_resource_to_staging_dir(struct wim_inode *inode, * At the same time, we need to count the number of these opened * file descriptors to the new lookup table entry. If there's * an old lookup table entry, this number needs to be subtracted - * from the fd's opened to the old entry. */ + * from the fd's opened to the old entry. */ for (u16 i = 0, j = 0; j < inode->i_num_opened_fds; i++) { - struct wimfs_fd *fd = inode->i_fds[i]; - if (fd) { - if (fd->stream_id == stream_id) { - int raw_fd; - - wimlib_assert(fd->f_lte == old_lte); - wimlib_assert(!filedes_valid(&fd->staging_fd)); - fd->f_lte = new_lte; - new_lte->num_opened_fds++; - raw_fd = open(staging_file_name, O_RDONLY); - if (raw_fd < 0) { - ret = -errno; - goto out_revert_fd_changes; - } - filedes_init(&fd->staging_fd, raw_fd); - } - j++; + struct wimfs_fd *fd; + int raw_fd; + + fd = inode->i_fds[i]; + if (!fd) + continue; + + j++; + + if (fd->f_stream_id != stream_id) + continue; + + /* This is a readonly fd for the same stream. */ + fd->f_lte = new_lte; + new_lte->num_opened_fds++; + raw_fd = openat(ctx->staging_dir_fd, staging_file_name, + O_RDONLY | O_NOFOLLOW); + if (unlikely(raw_fd < 0)) { + ret = -errno; + goto out_revert_fd_changes; } + filedes_init(&fd->f_staging_fd, raw_fd); } - DEBUG("%hu fd's were already opened to the file we extracted", - new_lte->num_opened_fds); if (old_lte) { old_lte->num_opened_fds -= new_lte->num_opened_fds; old_lte->refcnt -= inode->i_nlink; } } - lte_put_resource(new_lte); - new_lte->refcnt = inode->i_nlink; - new_lte->resource_location = RESOURCE_IN_STAGING_FILE; - new_lte->staging_file_name = staging_file_name; - new_lte->size = size; + new_lte->refcnt = inode->i_nlink; + new_lte->resource_location = RESOURCE_IN_STAGING_FILE; + new_lte->staging_file_name = staging_file_name; + new_lte->staging_dir_fd = ctx->staging_dir_fd; + new_lte->size = size; add_unhashed_stream(new_lte, inode, stream_id, &wim_get_current_image_metadata(ctx->wim)->unhashed_streams); - *retrieve_lte_pointer(new_lte) = new_lte; - *lte = new_lte; + if (stream_idx == 0) + inode->i_lte = new_lte; + else + inode->i_ads_entries[stream_idx - 1].lte = new_lte; + *lte_ptr = new_lte; return 0; + out_revert_fd_changes: - for (u16 i = 0, j = 0; j < new_lte->num_opened_fds; i++) { + for (u16 i = 0; new_lte->num_opened_fds; i++) { struct wimfs_fd *fd = inode->i_fds[i]; - if (fd && fd->stream_id == stream_id && fd->f_lte == new_lte) { + if (fd && fd->f_stream_id == stream_id) { fd->f_lte = old_lte; - if (filedes_valid(&fd->staging_fd)) { - filedes_close(&fd->staging_fd); - filedes_invalidate(&fd->staging_fd); + if (filedes_valid(&fd->f_staging_fd)) { + filedes_close(&fd->f_staging_fd); + filedes_invalidate(&fd->f_staging_fd); } - j++; + new_lte->num_opened_fds--; } } free_lookup_table_entry(new_lte); out_delete_staging_file: - unlink(staging_file_name); + unlinkat(ctx->staging_dir_fd, staging_file_name, 0); FREE(staging_file_name); return ret; } /* - * Creates a randomly named staging directory and saves its name in the - * filesystem context structure. + * Create the staging directory for the WIM file. + * + * The staging directory will be created in the directory specified by the open + * file descriptor @parent_dir_fd. It will be given a randomly generated name + * based on @wim_basename, the name of the WIM file. + * + * On success, returns a file descriptor to the open staging directory with + * O_RDONLY access. In addition, stores the allocated name of the staging + * directory (relative to @parent_dir_fd) in @staging_dir_name_ret. + * On failure, returns -1 and sets errno. */ static int -make_staging_dir(struct wimfs_context *ctx, const char *user_prefix) +make_staging_dir_at(int parent_dir_fd, const char *wim_basename, + char **staging_dir_name_ret) { + static const char common_suffix[8] = ".staging"; static const size_t random_suffix_len = 10; - static const char *common_suffix = ".staging"; - static const size_t common_suffix_len = 8; - - char *staging_dir_name = NULL; + size_t wim_basename_len; size_t staging_dir_name_len; - size_t prefix_len; - const char *wim_basename; - char *real_user_prefix = NULL; - int ret; - - if (user_prefix) { - real_user_prefix = realpath(user_prefix, NULL); - if (!real_user_prefix) { - ERROR_WITH_ERRNO("Could not resolve `%s'", - real_user_prefix); - ret = WIMLIB_ERR_NOTDIR; - goto out; - } - wim_basename = path_basename(ctx->wim->filename); - prefix_len = strlen(real_user_prefix) + 1 + strlen(wim_basename); - } else { - prefix_len = strlen(ctx->wim->filename); - } - - staging_dir_name_len = prefix_len + common_suffix_len + random_suffix_len; + char *staging_dir_name; + char *p; + int fd; + wim_basename_len = strlen(wim_basename); + staging_dir_name_len = wim_basename_len + sizeof(common_suffix) + + random_suffix_len; staging_dir_name = MALLOC(staging_dir_name_len + 1); - if (!staging_dir_name) { - ret = WIMLIB_ERR_NOMEM; - goto out; - } - - if (real_user_prefix) - sprintf(staging_dir_name, "%s/%s", real_user_prefix, wim_basename); - else - strcpy(staging_dir_name, ctx->wim->filename); + if (!staging_dir_name) + return -1; - strcat(staging_dir_name, common_suffix); + p = staging_dir_name; + p = mempcpy(p, wim_basename, wim_basename_len); + p = mempcpy(p, common_suffix, sizeof(common_suffix)); + randomize_char_array_with_alnum(p, random_suffix_len); + p += random_suffix_len; + *p = '\0'; - randomize_char_array_with_alnum(staging_dir_name + prefix_len + common_suffix_len, - random_suffix_len); + if (mkdirat(parent_dir_fd, staging_dir_name, 0700)) + goto err1; - staging_dir_name[staging_dir_name_len] = '\0'; + fd = openat(parent_dir_fd, staging_dir_name, + O_RDONLY | O_DIRECTORY | O_NOFOLLOW); + if (fd < 0) + goto err2; - if (mkdir(staging_dir_name, 0700) != 0) { - ERROR_WITH_ERRNO("Failed to create temporary directory `%s'", - staging_dir_name); - ret = WIMLIB_ERR_MKDIR; - } else { - ret = 0; - } -out: - FREE(real_user_prefix); - if (ret == 0) { - ctx->staging_dir_name = staging_dir_name; - ctx->staging_dir_name_len = staging_dir_name_len; - } else { - FREE(staging_dir_name); - } - return ret; -} + *staging_dir_name_ret = staging_dir_name; + return fd; -static int -remove_file_or_directory(const char *fpath, const struct stat *sb, - int typeflag, struct FTW *ftwbuf) -{ - if (remove(fpath) == 0) - return 0; - else { - ERROR_WITH_ERRNO("Cannot remove `%s'", fpath); - return WIMLIB_ERR_DELETE_STAGING_DIR; - } +err2: + unlinkat(parent_dir_fd, staging_dir_name, AT_REMOVEDIR); +err1: + FREE(staging_dir_name); + return -1; } /* - * Deletes the staging directory and all the files contained in it. + * Create the staging directory and set ctx->staging_dir_fd, + * ctx->staging_dir_name, and ctx->parent_dir_fd. */ static int -delete_staging_dir(struct wimfs_context *ctx) +make_staging_dir(struct wimfs_context *ctx, const char *parent_dir_path) { + const char *wim_basename; + char *end = NULL; int ret; - ret = nftw(ctx->staging_dir_name, remove_file_or_directory, - 10, FTW_DEPTH); - FREE(ctx->staging_dir_name); - ctx->staging_dir_name = NULL; - return ret; -} -static int -inode_close_fds(struct wim_inode *inode) -{ - u16 num_opened_fds = inode->i_num_opened_fds; - for (u16 i = 0, j = 0; j < num_opened_fds; i++) { - struct wimfs_fd *fd = inode->i_fds[i]; - if (fd) { - wimlib_assert(fd->f_inode == inode); - int ret = close_wimfs_fd(fd); - if (ret != 0) - return ret; - j++; + wim_basename = path_basename(ctx->wim->filename); + + if (!parent_dir_path) { + /* The user did not specify a directory. Default to creating + * the staging directory alongside the WIM file. */ + if (wim_basename > ctx->wim->filename) { + parent_dir_path = ctx->wim->filename; + end = (char *)(wim_basename - 1); + /* *end must be a slash. Temporarily overwrite it so we + * can open the parent directory. */ + *end = '\0'; + } else { + parent_dir_path = "."; } } - return 0; -} - -/* Overwrites the WIM file, with changes saved. */ -static int -rebuild_wim(struct wimfs_context *ctx, int write_flags) -{ - int ret; - struct wim_lookup_table_entry *lte, *tmp; - WIMStruct *wim = ctx->wim; - struct wim_image_metadata *imd = wim_get_current_image_metadata(ctx->wim); - DEBUG("Closing all staging file descriptors."); - image_for_each_unhashed_stream_safe(lte, tmp, imd) { - ret = inode_close_fds(lte->back_inode); - if (ret) - return ret; + /* Open the parent directory (in which we'll create our staging + * directory). */ + ctx->parent_dir_fd = open(parent_dir_path, O_RDONLY | O_DIRECTORY); + if (ctx->parent_dir_fd < 0) { + ERROR_WITH_ERRNO("Can't open directory \"%s\"", + parent_dir_path); + ret = WIMLIB_ERR_OPENDIR; + goto out_restore_wim_filename; } - DEBUG("Freeing entries for zero-length streams"); - image_for_each_unhashed_stream_safe(lte, tmp, imd) { - wimlib_assert(lte->unhashed); - if (lte->size == 0) { - struct wim_lookup_table_entry **back_ptr; - back_ptr = retrieve_lte_pointer(lte); - *back_ptr = NULL; - list_del(<e->unhashed_list); - free_lookup_table_entry(lte); - } + ctx->staging_dir_fd = make_staging_dir_at(ctx->parent_dir_fd, + wim_basename, + &ctx->staging_dir_name); + if (ctx->staging_dir_fd < 0) { + ERROR_WITH_ERRNO("Can't create staging directory in \"%s\"", + parent_dir_path); + close(ctx->parent_dir_fd); + ret = WIMLIB_ERR_MKDIR; + goto out_restore_wim_filename; } - - xml_update_image_info(wim, wim->current_image); - ret = wimlib_overwrite(wim, write_flags, 0); - if (ret) - ERROR("Failed to commit changes to mounted WIM image"); + ret = 0; +out_restore_wim_filename: + if (end) + *end = '/'; return ret; } -/* Simple function that returns the concatenation of 2 strings. */ -static char * -strcat_dup(const char *s1, const char *s2, size_t max_len) +/* Deletes the staging directory, undoing the effects of a succesful call to + * make_staging_dir(). */ +static void +delete_staging_dir(struct wimfs_context *ctx) { - size_t len = strlen(s1) + strlen(s2); - if (len > max_len) - len = max_len; - char *p = MALLOC(len + 1); - if (!p) - return NULL; - snprintf(p, len + 1, "%s%s", s1, s2); - return p; + DIR *dir; + struct dirent *ent; + + dir = fdopendir(ctx->staging_dir_fd); + if (dir) { + while ((ent = readdir(dir))) + unlinkat(ctx->staging_dir_fd, ent->d_name, 0); + closedir(dir); + } else { + close(ctx->staging_dir_fd); + } + if (unlinkat(ctx->parent_dir_fd, ctx->staging_dir_name, AT_REMOVEDIR)) + WARNING_WITH_ERRNO("Could not delete staging directory"); + FREE(ctx->staging_dir_name); + close(ctx->parent_dir_fd); } -static int -set_message_queue_names(struct wimfs_context *ctx, const char *mount_dir) +static void +reassign_inode_numbers(struct wimfs_context *ctx) { - static const char *u2d_prefix = "/wimlib-unmount-to-daemon-mq"; - static const char *d2u_prefix = "/wimlib-daemon-to-unmount-mq"; - char *dir_path; - char *p; - int ret; - - dir_path = realpath(mount_dir, NULL); - if (!dir_path) { - ERROR_WITH_ERRNO("Failed to resolve path \"%s\"", mount_dir); - if (errno == ENOMEM) - return WIMLIB_ERR_NOMEM; - else - return WIMLIB_ERR_NOTDIR; - } + struct wim_image_metadata *imd; + struct wim_inode *inode; - for (p = dir_path; *p; p++) - if (*p == '/') - *p = 0xff; - - ctx->unmount_to_daemon_mq_name = strcat_dup(u2d_prefix, dir_path, - NAME_MAX); - if (!ctx->unmount_to_daemon_mq_name) { - ret = WIMLIB_ERR_NOMEM; - goto out_free_dir_path; - } - ctx->daemon_to_unmount_mq_name = strcat_dup(d2u_prefix, dir_path, - NAME_MAX); - if (!ctx->daemon_to_unmount_mq_name) { - ret = WIMLIB_ERR_NOMEM; - goto out_free_unmount_to_daemon_mq_name; - } - - ret = 0; - goto out_free_dir_path; -out_free_unmount_to_daemon_mq_name: - FREE(ctx->unmount_to_daemon_mq_name); - ctx->unmount_to_daemon_mq_name = NULL; -out_free_dir_path: - FREE(dir_path); - return ret; -} + ctx->next_ino = 1; + imd = wim_get_current_image_metadata(ctx->wim); + image_for_each_inode(inode, imd) + inode->i_ino = ctx->next_ino++; +} static void -free_message_queue_names(struct wimfs_context *ctx) -{ - FREE(ctx->unmount_to_daemon_mq_name); - FREE(ctx->daemon_to_unmount_mq_name); - ctx->unmount_to_daemon_mq_name = NULL; - ctx->daemon_to_unmount_mq_name = NULL; -} - -/* - * Opens two POSIX message queue: one for sending messages from the unmount - * process to the daemon process, and one to go the other way. The names of the - * message queues, which must be system-wide unique, are be based on the mount - * point. - * - * @daemon specifies whether the calling process is the filesystem daemon or the - * unmount process. - */ -static int -open_message_queues(struct wimfs_context *ctx, bool daemon) -{ - int unmount_to_daemon_mq_flags = O_WRONLY | O_CREAT; - int daemon_to_unmount_mq_flags = O_RDONLY | O_CREAT; - mode_t mode; - mode_t orig_umask; - int ret; - - if (daemon) { - swap(unmount_to_daemon_mq_flags, daemon_to_unmount_mq_flags); - mode = 0600; - } else { - mode = 0666; - } - - orig_umask = umask(0000); - DEBUG("Opening message queue \"%s\"", ctx->unmount_to_daemon_mq_name); - ctx->unmount_to_daemon_mq = mq_open(ctx->unmount_to_daemon_mq_name, - unmount_to_daemon_mq_flags, mode, NULL); - - if (ctx->unmount_to_daemon_mq == (mqd_t)-1) { - ERROR_WITH_ERRNO("mq_open()"); - ret = WIMLIB_ERR_MQUEUE; - goto out; - } - - DEBUG("Opening message queue \"%s\"", ctx->daemon_to_unmount_mq_name); - ctx->daemon_to_unmount_mq = mq_open(ctx->daemon_to_unmount_mq_name, - daemon_to_unmount_mq_flags, mode, NULL); - - if (ctx->daemon_to_unmount_mq == (mqd_t)-1) { - ERROR_WITH_ERRNO("mq_open()"); - mq_close(ctx->unmount_to_daemon_mq); - mq_unlink(ctx->unmount_to_daemon_mq_name); - ctx->unmount_to_daemon_mq = (mqd_t)-1; - ret = WIMLIB_ERR_MQUEUE; - goto out; - } - ret = 0; -out: - umask(orig_umask); - return ret; -} - -/* Try to determine the maximum message size of a message queue. The return - * value is the maximum message size, or a guess of 8192 bytes if it cannot be - * determined. */ -static long -mq_get_msgsize(mqd_t mq) -{ - static const char *msgsize_max_file = "/proc/sys/fs/mqueue/msgsize_max"; - FILE *fp; - struct mq_attr attr; - long msgsize; - - if (mq_getattr(mq, &attr) == 0) { - msgsize = attr.mq_msgsize; - } else { - ERROR_WITH_ERRNO("mq_getattr()"); - ERROR("Attempting to read %s", msgsize_max_file); - fp = fopen(msgsize_max_file, "rb"); - if (fp) { - if (fscanf(fp, "%ld", &msgsize) != 1) { - ERROR("Assuming message size of 8192"); - msgsize = 8192; - } - fclose(fp); - } else { - ERROR_WITH_ERRNO("Failed to open the file `%s'", - msgsize_max_file); - ERROR("Assuming message size of 8192"); - msgsize = 8192; - } - } - return msgsize; -} - -static int -get_mailbox(mqd_t mq, long needed_msgsize, long *msgsize_ret, - void **mailbox_ret) +release_extra_refcnts(struct wimfs_context *ctx) { - long msgsize; - void *mailbox; - - msgsize = mq_get_msgsize(mq); - - if (msgsize < needed_msgsize) { - ERROR("Message queue max size must be at least %ld!", - needed_msgsize); - return WIMLIB_ERR_MQUEUE; - } + struct list_head *list = &ctx->orig_stream_list; + struct wim_lookup_table *lookup_table = ctx->wim->lookup_table; + struct wim_lookup_table_entry *lte, *tmp; - mailbox = MALLOC(msgsize); - if (!mailbox) { - ERROR("Failed to allocate %ld bytes for mailbox", msgsize); - return WIMLIB_ERR_NOMEM; + list_for_each_entry_safe(lte, tmp, list, orig_stream_list) { + u32 n = lte->out_refcnt; + while (n--) + lte_decrement_refcnt(lte, lookup_table); } - *msgsize_ret = msgsize; - *mailbox_ret = mailbox; - return 0; } static void -unlink_message_queues(struct wimfs_context *ctx) +delete_empty_streams(struct wimfs_context *ctx) { - mq_unlink(ctx->unmount_to_daemon_mq_name); - mq_unlink(ctx->daemon_to_unmount_mq_name); -} - -/* Closes the message queues, which are allocated in static variables */ -static void -close_message_queues(struct wimfs_context *ctx) -{ - DEBUG("Closing message queues"); - mq_close(ctx->unmount_to_daemon_mq); - ctx->unmount_to_daemon_mq = (mqd_t)(-1); - mq_close(ctx->daemon_to_unmount_mq); - ctx->daemon_to_unmount_mq = (mqd_t)(-1); - unlink_message_queues(ctx); -} - - -struct unmount_msg_hdr { - u32 min_version; - u32 cur_version; - u32 msg_type; - u32 msg_size; -} _packed_attribute; - -struct msg_unmount_request { - struct unmount_msg_hdr hdr; - u32 unmount_flags; - u8 want_progress_messages; -} _packed_attribute; - -struct msg_daemon_info { - struct unmount_msg_hdr hdr; - pid_t daemon_pid; - u32 mount_flags; -} _packed_attribute; - -struct msg_unmount_finished { - struct unmount_msg_hdr hdr; - s32 status; -} _packed_attribute; - -struct msg_write_streams_progress { - struct unmount_msg_hdr hdr; - union wimlib_progress_info info; -} _packed_attribute; - -enum { - MSG_TYPE_UNMOUNT_REQUEST, - MSG_TYPE_DAEMON_INFO, - MSG_TYPE_WRITE_STREAMS_PROGRESS, - MSG_TYPE_UNMOUNT_FINISHED, - MSG_TYPE_MAX, -}; - -struct msg_handler_context_hdr { - int timeout_seconds; -}; - -struct unmount_msg_handler_context { - struct msg_handler_context_hdr hdr; - pid_t daemon_pid; - int mount_flags; - int status; - wimlib_progress_func_t progfunc; - void *progctx; -}; - -struct daemon_msg_handler_context { - struct msg_handler_context_hdr hdr; - struct wimfs_context *wimfs_ctx; -}; + struct wim_lookup_table_entry *lte, *tmp; + struct wim_image_metadata *imd; -static int -send_unmount_request_msg(mqd_t mq, int unmount_flags, u8 want_progress_messages) -{ - DEBUG("Sending unmount request msg"); - struct msg_unmount_request msg = { - .hdr = { - .min_version = ((unmount_flags & WIMLIB_UNMOUNT_FLAG_NEW_IMAGE) ? - WIMLIB_MAKEVERSION(1, 6, 2) : - WIMLIB_MAKEVERSION(1, 2, 1)), - .cur_version = WIMLIB_VERSION_CODE, - .msg_type = MSG_TYPE_UNMOUNT_REQUEST, - .msg_size = sizeof(msg), - }, - .unmount_flags = unmount_flags, - .want_progress_messages = want_progress_messages, - }; - - if (mq_send(mq, (void*)&msg, sizeof(msg), 1)) { - ERROR_WITH_ERRNO("Failed to communicate with filesystem daemon"); - return WIMLIB_ERR_MQUEUE; - } - return 0; -} + imd = wim_get_current_image_metadata(ctx->wim); -static int -send_daemon_info_msg(mqd_t mq, pid_t pid, int mount_flags) -{ - DEBUG("Sending daemon info msg (pid = %d, mount_flags=%x)", - pid, mount_flags); - - struct msg_daemon_info msg = { - .hdr = { - .min_version = WIMLIB_MAKEVERSION(1, 2, 1), - .cur_version = WIMLIB_VERSION_CODE, - .msg_type = MSG_TYPE_DAEMON_INFO, - .msg_size = sizeof(msg), - }, - .daemon_pid = pid, - .mount_flags = mount_flags, - }; - if (mq_send(mq, (void*)&msg, sizeof(msg), 1)) { - ERROR_WITH_ERRNO("Failed to send daemon info to unmount process"); - return WIMLIB_ERR_MQUEUE; - } - return 0; + image_for_each_unhashed_stream_safe(lte, tmp, imd) { + if (!lte->size) { + *retrieve_lte_pointer(lte) = NULL; + list_del(<e->unhashed_list); + free_lookup_table_entry(lte); + } + } } static void -send_unmount_finished_msg(mqd_t mq, int status) -{ - DEBUG("Sending unmount finished msg"); - struct msg_unmount_finished msg = { - .hdr = { - .min_version = WIMLIB_MAKEVERSION(1, 2, 1), - .cur_version = WIMLIB_VERSION_CODE, - .msg_type = MSG_TYPE_UNMOUNT_FINISHED, - .msg_size = sizeof(msg), - }, - .status = status, - }; - if (mq_send(mq, (void*)&msg, sizeof(msg), 1)) - ERROR_WITH_ERRNO("Failed to send status to unmount process"); -} - -static enum wimlib_progress_status -unmount_progress_func(enum wimlib_progress_msg msg, - union wimlib_progress_info *info, void *_ignored_context) -{ - if (msg == WIMLIB_PROGRESS_MSG_WRITE_STREAMS) { - struct msg_write_streams_progress msg = { - .hdr = { - .min_version = WIMLIB_MAKEVERSION(1, 2, 1), - .cur_version = WIMLIB_VERSION_CODE, - .msg_type = MSG_TYPE_WRITE_STREAMS_PROGRESS, - .msg_size = sizeof(msg), - }, - .info = *info, - }; - if (mq_send(wimfs_get_context()->daemon_to_unmount_mq, - (void*)&msg, sizeof(msg), 1)) - { - ERROR_WITH_ERRNO("Failed to send progress information " - "to unmount process"); +inode_close_fds(struct wim_inode *inode) +{ + u16 num_open_fds = inode->i_num_opened_fds; + for (u16 i = 0; num_open_fds; i++) { + if (inode->i_fds[i]) { + close_wimfs_fd(inode->i_fds[i]); + num_open_fds--; } } - return WIMLIB_PROGRESS_STATUS_CONTINUE; } static void -release_extra_refcnts(struct wimfs_context *ctx) +close_all_fds(struct wimfs_context *ctx) { - struct list_head *list = &ctx->orig_stream_list; - struct wim_lookup_table *lookup_table = ctx->wim->lookup_table; - struct wim_lookup_table_entry *lte, *tmp; + struct wim_inode *inode, *tmp; + struct wim_image_metadata *imd; - list_for_each_entry_safe(lte, tmp, list, orig_stream_list) { - u32 n = lte->out_refcnt; - while (n--) - lte_decrement_refcnt(lte, lookup_table); - } + imd = wim_get_current_image_metadata(ctx->wim); + + list_for_each_entry_safe(inode, tmp, &imd->inode_list, i_list) + inode_close_fds(inode); } /* Moves the currently selected image, which may have been modified, to a new @@ -1211,23 +960,18 @@ static int renew_current_image(struct wimfs_context *ctx) { WIMStruct *wim = ctx->wim; - int ret; int idx = wim->current_image - 1; struct wim_image_metadata *imd = wim->image_metadata[idx]; struct wim_image_metadata *replace_imd; struct wim_lookup_table_entry *new_lte; - - if (imd->metadata_lte->resource_location != RESOURCE_IN_WIM) { - ERROR("Can't reset modified image that doesn't yet " - "exist in the on-disk WIM file!"); - return WIMLIB_ERR_METADATA_NOT_FOUND; - } + int ret; /* Create 'replace_imd' structure to use for the reset original, * unmodified image. */ + ret = WIMLIB_ERR_NOMEM; replace_imd = new_image_metadata(); if (!replace_imd) - return WIMLIB_ERR_NOMEM; + goto err; /* Create new stream reference for the modified image's metadata * resource, which doesn't exist yet. */ @@ -1261,386 +1005,124 @@ err_free_new_lte: free_lookup_table_entry(new_lte); err_put_replace_imd: put_image_metadata(replace_imd, NULL); +err: return ret; } -static int -msg_unmount_request_handler(const void *_msg, void *_handler_ctx) -{ - const struct msg_unmount_request *msg = _msg; - struct daemon_msg_handler_context *handler_ctx = _handler_ctx; - struct wimfs_context *wimfs_ctx; - int status = 0; - int ret; - int unmount_flags; - - DEBUG("Handling unmount request msg"); - - wimfs_ctx = handler_ctx->wimfs_ctx; - if (msg->hdr.msg_size < sizeof(*msg)) { - status = WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; - goto out; - } - - unmount_flags = msg->unmount_flags; - - wimlib_register_progress_function(wimfs_ctx->wim, - (msg->want_progress_messages ? - unmount_progress_func : NULL), - NULL); - - ret = send_daemon_info_msg(wimfs_ctx->daemon_to_unmount_mq, getpid(), - wimfs_ctx->mount_flags); - if (ret != 0) { - status = ret; - goto out; - } - - if (wimfs_ctx->mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { - if (unmount_flags & WIMLIB_UNMOUNT_FLAG_COMMIT) { - - if (unmount_flags & WIMLIB_UNMOUNT_FLAG_NEW_IMAGE) { - ret = renew_current_image(wimfs_ctx); - if (ret) { - status = ret; - goto out; - } - } else { - release_extra_refcnts(wimfs_ctx); - } - INIT_LIST_HEAD(&wimfs_ctx->orig_stream_list); - - int write_flags = 0; - if (unmount_flags & WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY) - write_flags |= WIMLIB_WRITE_FLAG_CHECK_INTEGRITY; - if (unmount_flags & WIMLIB_UNMOUNT_FLAG_REBUILD) - write_flags |= WIMLIB_WRITE_FLAG_REBUILD; - if (unmount_flags & WIMLIB_UNMOUNT_FLAG_RECOMPRESS) - write_flags |= WIMLIB_WRITE_FLAG_RECOMPRESS; - status = rebuild_wim(wimfs_ctx, write_flags); - } - } else { - DEBUG("Read-only mount"); - status = 0; - } - -out: - if (wimfs_ctx->mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { - ret = delete_staging_dir(wimfs_ctx); - if (ret != 0) { - ERROR("Failed to delete the staging directory"); - if (status == 0) - status = ret; - } - } - wimfs_ctx->status = status; - wimfs_ctx->have_status = true; - return MSG_BREAK_LOOP; -} - -static int -msg_daemon_info_handler(const void *_msg, void *_handler_ctx) -{ - const struct msg_daemon_info *msg = _msg; - struct unmount_msg_handler_context *handler_ctx = _handler_ctx; - - DEBUG("Handling daemon info msg"); - if (msg->hdr.msg_size < sizeof(*msg)) - return WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; - handler_ctx->daemon_pid = msg->daemon_pid; - handler_ctx->mount_flags = msg->mount_flags; - handler_ctx->hdr.timeout_seconds = 1; - DEBUG("pid of daemon is %d; mount flags were %#x", - handler_ctx->daemon_pid, - handler_ctx->mount_flags); - return 0; -} - -static int -msg_write_streams_progress_handler(const void *_msg, void *_handler_ctx) -{ - const struct msg_write_streams_progress *msg = _msg; - struct unmount_msg_handler_context *handler_ctx = _handler_ctx; - - if (msg->hdr.msg_size < sizeof(*msg)) - return WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; - return call_progress(handler_ctx->progfunc, - WIMLIB_PROGRESS_MSG_WRITE_STREAMS, - (union wimlib_progress_info *)&msg->info, - handler_ctx->progctx); -} - -static int -msg_unmount_finished_handler(const void *_msg, void *_handler_ctx) -{ - const struct msg_unmount_finished *msg = _msg; - struct unmount_msg_handler_context *handler_ctx = _handler_ctx; - - DEBUG("Handling unmount finished message"); - if (msg->hdr.msg_size < sizeof(*msg)) - return WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; - handler_ctx->status = msg->status; - DEBUG("status is %d", handler_ctx->status); - return MSG_BREAK_LOOP; -} - -static int -unmount_timed_out_cb(void *_handler_ctx) +static enum wimlib_progress_status +commit_progress_func(enum wimlib_progress_msg msg, + union wimlib_progress_info *info, void *progctx) { - const struct unmount_msg_handler_context *handler_ctx = _handler_ctx; + mqd_t mq = *(mqd_t *)progctx; + struct commit_progress_report report; - if (handler_ctx->daemon_pid == 0 || - (kill(handler_ctx->daemon_pid, 0) != 0 && errno == ESRCH)) - { - ERROR("The filesystem daemon has crashed! Changes to the " - "WIM may not have been commited."); - return WIMLIB_ERR_FILESYSTEM_DAEMON_CRASHED; - } - - DEBUG("Filesystem daemon is still alive... " - "Waiting another %d seconds", handler_ctx->hdr.timeout_seconds); - return 0; + memset(&report, 0, sizeof(report)); + report.msg = msg; + if (info) + report.info = *info; + mq_send(mq, (const char *)&report, sizeof(report), 1); + return WIMLIB_PROGRESS_STATUS_CONTINUE; } +/* Commit the mounted image to the underlying WIM file. */ static int -daemon_timed_out_cb(void *_handler_ctx) +commit_image(struct wimfs_context *ctx, int unmount_flags, mqd_t mq) { - ERROR("Timed out waiting for unmount request! " - "Changes to the mounted WIM will not be committed."); - return WIMLIB_ERR_TIMEOUT; -} - -typedef int (*msg_handler_t)(const void *_msg, void *_handler_ctx); - -struct msg_handler_callbacks { - int (*timed_out)(void * _handler_ctx); - msg_handler_t msg_handlers[MSG_TYPE_MAX]; -}; - -static const struct msg_handler_callbacks unmount_msg_handler_callbacks = { - .timed_out = unmount_timed_out_cb, - .msg_handlers = { - [MSG_TYPE_DAEMON_INFO] = msg_daemon_info_handler, - [MSG_TYPE_WRITE_STREAMS_PROGRESS] = msg_write_streams_progress_handler, - [MSG_TYPE_UNMOUNT_FINISHED] = msg_unmount_finished_handler, - }, -}; - -static const struct msg_handler_callbacks daemon_msg_handler_callbacks = { - .timed_out = daemon_timed_out_cb, - .msg_handlers = { - [MSG_TYPE_UNMOUNT_REQUEST] = msg_unmount_request_handler, - }, -}; - -static int -receive_message(mqd_t mq, - struct msg_handler_context_hdr *handler_ctx, - const msg_handler_t msg_handlers[], - long mailbox_size, void *mailbox) -{ - struct timeval now; - struct timespec timeout; - ssize_t bytes_received; - struct unmount_msg_hdr *hdr; - int ret; + int write_flags; - gettimeofday(&now, NULL); - timeout.tv_sec = now.tv_sec + handler_ctx->timeout_seconds; - timeout.tv_nsec = now.tv_usec * 1000; + if (unmount_flags & WIMLIB_UNMOUNT_FLAG_SEND_PROGRESS) + wimlib_register_progress_function(ctx->wim, + commit_progress_func, &mq); + else + wimlib_register_progress_function(ctx->wim, NULL, NULL); - bytes_received = mq_timedreceive(mq, mailbox, - mailbox_size, NULL, &timeout); - hdr = mailbox; - if (bytes_received == -1) { - if (errno == ETIMEDOUT) { - ret = WIMLIB_ERR_TIMEOUT; - } else { - ERROR_WITH_ERRNO("mq_timedreceive()"); - ret = WIMLIB_ERR_MQUEUE; - } - } else if (bytes_received < sizeof(*hdr) || - bytes_received != hdr->msg_size) { - ret = WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; - } else if (WIMLIB_VERSION_CODE < hdr->min_version) { - /*ERROR("Cannot understand the received message. "*/ - /*"Please upgrade wimlib to at least v%d.%d.%d",*/ - /*WIMLIB_GET_MAJOR_VERSION(hdr->min_version),*/ - /*WIMLIB_GET_MINOR_VERSION(hdr->min_version),*/ - /*WIMLIB_GET_PATCH_VERSION(hdr->min_version));*/ - ret = MSG_VERSION_TOO_HIGH; - } else if (hdr->msg_type >= MSG_TYPE_MAX) { - ret = WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; - } else if (msg_handlers[hdr->msg_type] == NULL) { - ret = WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE; + if (unmount_flags & WIMLIB_UNMOUNT_FLAG_NEW_IMAGE) { + int ret = renew_current_image(ctx); + if (ret) + return ret; } else { - ret = msg_handlers[hdr->msg_type](mailbox, handler_ctx); + release_extra_refcnts(ctx); } - return ret; -} - -static int -message_loop(mqd_t mq, - const struct msg_handler_callbacks *callbacks, - struct msg_handler_context_hdr *handler_ctx) -{ - static const size_t MAX_MSG_SIZE = 512; - long msgsize; - void *mailbox; - int ret; - - DEBUG("Entering message loop"); + INIT_LIST_HEAD(&ctx->orig_stream_list); + delete_empty_streams(ctx); + xml_update_image_info(ctx->wim, ctx->wim->current_image); - ret = get_mailbox(mq, MAX_MSG_SIZE, &msgsize, &mailbox); - if (ret != 0) - return ret; - while (1) { - ret = receive_message(mq, handler_ctx, - callbacks->msg_handlers, - msgsize, mailbox); - if (ret == 0 || ret == MSG_VERSION_TOO_HIGH) { - continue; - } else if (ret == MSG_BREAK_LOOP) { - ret = 0; - break; - } else if (ret == WIMLIB_ERR_TIMEOUT) { - if (callbacks->timed_out) - ret = callbacks->timed_out(handler_ctx); - if (ret == 0) - continue; - else - break; - } else { - ERROR_WITH_ERRNO("Error communicating with " - "filesystem daemon"); - break; - } - } - FREE(mailbox); - DEBUG("Exiting message loop"); - return ret; + write_flags = 0; + if (unmount_flags & WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY) + write_flags |= WIMLIB_WRITE_FLAG_CHECK_INTEGRITY; + if (unmount_flags & WIMLIB_UNMOUNT_FLAG_REBUILD) + write_flags |= WIMLIB_WRITE_FLAG_REBUILD; + if (unmount_flags & WIMLIB_UNMOUNT_FLAG_RECOMPRESS) + write_flags |= WIMLIB_WRITE_FLAG_RECOMPRESS; + return wimlib_overwrite(ctx->wim, write_flags, 0); } -/* Execute `fusermount -u', which is installed setuid root, to unmount the WIM. - * - * FUSE does not yet implement synchronous unmounts. This means that fusermount - * -u will return before the filesystem daemon returns from wimfs_destroy(). - * This is partly what we want, because we need to send a message from this - * process to the filesystem daemon telling whether --commit was specified or - * not. However, after that, the unmount process must wait for the filesystem - * daemon to finish writing the WIM file. - */ static int -execute_fusermount(const char *dir, bool lazy) +unmount_wimfs(const struct wimfs_unmount_info *info) { - pid_t pid; - int ret; + struct fuse_context *fuse_ctx = fuse_get_context(); + struct wimfs_context *wimfs_ctx = WIMFS_CTX(fuse_ctx); + int unmount_flags = info->unmount_flags; + mqd_t mq = (mqd_t)-1; int status; - pid = fork(); - if (pid == -1) { - ERROR_WITH_ERRNO("Failed to fork()"); - return WIMLIB_ERR_FORK; - } - if (pid == 0) { - /* Child */ - char *argv[10]; - char **argp = argv; - *argp++ = "fusermount"; - if (lazy) - *argp++ = "-z"; - *argp++ = "-u"; - *argp++ = (char*)dir; - *argp = NULL; - execvp("fusermount", argv); - ERROR_WITH_ERRNO("Failed to execute `fusermount'"); - exit(WIMLIB_ERR_FUSERMOUNT); - } - - /* Parent */ - ret = waitpid(pid, &status, 0); - if (ret == -1) { - ERROR_WITH_ERRNO("Failed to wait for fusermount process to " - "terminate"); - return WIMLIB_ERR_FUSERMOUNT; - } + if (fuse_ctx->uid != wimfs_ctx->owner_uid && + fuse_ctx->uid != 0) + return -EPERM; - if (!WIFEXITED(status)) { - ERROR("'fusermount' did not terminate normally!"); - return WIMLIB_ERR_FUSERMOUNT; + if (info->mq_name[0]) { + mq = mq_open(info->mq_name, O_WRONLY | O_NONBLOCK); + if (mq == (mqd_t)-1) + return -errno; } - status = WEXITSTATUS(status); - - if (status == 0) - return 0; - - if (status != WIMLIB_ERR_FUSERMOUNT) - return WIMLIB_ERR_FUSERMOUNT; - - /* Try again, but with the `umount' program. This is required on other - * FUSE implementations such as FreeBSD's that do not have a - * `fusermount' program. */ - ERROR("Falling back to 'umount'. Note: you may need to be " - "root for this to work"); - pid = fork(); - if (pid == -1) { - ERROR_WITH_ERRNO("Failed to fork()"); - return WIMLIB_ERR_FORK; - } - if (pid == 0) { - /* Child */ - char *argv[10]; - char **argp = argv; - *argp++ = "umount"; - if (lazy) - *argp++ = "-l"; - *argp++ = (char*)dir; - *argp = NULL; - execvp("umount", argv); - ERROR_WITH_ERRNO("Failed to execute `umount'"); - exit(WIMLIB_ERR_FUSERMOUNT); - } + /* Ignore COMMIT if the image is mounted read-only. */ + if (!(wimfs_ctx->mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)) + unmount_flags &= ~WIMLIB_UNMOUNT_FLAG_COMMIT; - /* Parent */ - ret = waitpid(pid, &status, 0); - if (ret == -1) { - ERROR_WITH_ERRNO("Failed to wait for `umount' process to " - "terminate"); - return WIMLIB_ERR_FUSERMOUNT; + if (wimfs_ctx->num_open_fds) { + if ((unmount_flags & (WIMLIB_UNMOUNT_FLAG_COMMIT | + WIMLIB_UNMOUNT_FLAG_FORCE)) + == WIMLIB_UNMOUNT_FLAG_COMMIT) + { + status = WIMLIB_ERR_MOUNTED_IMAGE_IS_BUSY; + goto out_send_status; + } + close_all_fds(wimfs_ctx); } - if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { - ERROR("`umount' did not successfully complete"); - return WIMLIB_ERR_FUSERMOUNT; + if (unmount_flags & WIMLIB_UNMOUNT_FLAG_COMMIT) + status = commit_image(wimfs_ctx, unmount_flags, mq); + else + status = 0; + fuse_exit(fuse_ctx->fuse); +out_send_status: + if (mq != (mqd_t)-1) { + mq_send(mq, (const char *)&status, sizeof(int), 1); + mq_close(mq); } - return 0; } static int wimfs_chmod(const char *path, mode_t mask) { - struct wim_dentry *dentry; + const struct wimfs_context *ctx = wimfs_get_context(); struct wim_inode *inode; - struct wimfs_context *ctx = wimfs_get_context(); struct wimlib_unix_data unix_data; - int ret; if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_UNIX_DATA)) - return -EPERM; - - ret = wim_pathname_to_stream(ctx->wim, path, LOOKUP_FLAG_DIRECTORY_OK, - &dentry, NULL, NULL); - if (ret) - return ret; + return -EOPNOTSUPP; - inode = dentry->d_inode; + inode = wim_pathname_to_inode(ctx->wim, path); + if (!inode) + return -errno; - unix_data.uid = ctx->default_uid; - unix_data.gid = ctx->default_gid; + unix_data.uid = ctx->owner_uid; + unix_data.gid = ctx->owner_gid; unix_data.mode = mask; unix_data.rdev = 0; + if (!inode_set_unix_data(inode, &unix_data, UNIX_DATA_MODE)) return -ENOMEM; @@ -1650,163 +1132,173 @@ wimfs_chmod(const char *path, mode_t mask) static int wimfs_chown(const char *path, uid_t uid, gid_t gid) { - struct wim_dentry *dentry; + const struct wimfs_context *ctx = wimfs_get_context(); struct wim_inode *inode; - struct wimfs_context *ctx = wimfs_get_context(); - int which; struct wimlib_unix_data unix_data; - int ret; + int which; if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_UNIX_DATA)) - return -EPERM; - - ret = wim_pathname_to_stream(ctx->wim, path, LOOKUP_FLAG_DIRECTORY_OK, - &dentry, NULL, NULL); - if (ret) - return ret; + return -EOPNOTSUPP; - inode = dentry->d_inode; + inode = wim_pathname_to_inode(ctx->wim, path); + if (!inode) + return -errno; which = 0; if (uid != (uid_t)-1) which |= UNIX_DATA_UID; else - uid = ctx->default_uid; + uid = ctx->owner_uid; if (gid != (gid_t)-1) which |= UNIX_DATA_GID; else - gid = ctx->default_gid; - + gid = ctx->owner_gid; unix_data.uid = uid; unix_data.gid = gid; unix_data.mode = inode_default_unix_mode(inode); unix_data.rdev = 0; + if (!inode_set_unix_data(inode, &unix_data, which)) return -ENOMEM; return 0; } -/* Called when the filesystem is unmounted. */ -static void -wimfs_destroy(void *p) -{ - struct wimfs_context *wimfs_ctx = wimfs_get_context(); - if (open_message_queues(wimfs_ctx, true) == 0) { - struct daemon_msg_handler_context handler_ctx = { - .hdr = { - .timeout_seconds = 5, - }, - .wimfs_ctx = wimfs_ctx, - }; - message_loop(wimfs_ctx->unmount_to_daemon_mq, - &daemon_msg_handler_callbacks, - &handler_ctx.hdr); - } -} - static int -wimfs_fgetattr(const char *path, struct stat *stbuf, - struct fuse_file_info *fi) +wimfs_fgetattr(const char *path, struct stat *stbuf, struct fuse_file_info *fi) { - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; + struct wimfs_fd *fd = WIMFS_FD(fi); return inode_to_stbuf(fd->f_inode, fd->f_lte, stbuf); } static int wimfs_ftruncate(const char *path, off_t size, struct fuse_file_info *fi) { - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; - int ret = ftruncate(fd->staging_fd.fd, size); - if (ret) + struct wimfs_fd *fd = WIMFS_FD(fi); + if (ftruncate(fd->f_staging_fd.fd, size)) return -errno; touch_inode(fd->f_inode); fd->f_lte->size = size; return 0; } -/* - * Fills in a `struct stat' that corresponds to a file or directory in the WIM. - */ static int wimfs_getattr(const char *path, struct stat *stbuf) { + const struct wimfs_context *ctx = wimfs_get_context(); struct wim_dentry *dentry; struct wim_lookup_table_entry *lte; int ret; - struct wimfs_context *ctx = wimfs_get_context(); ret = wim_pathname_to_stream(ctx->wim, path, get_lookup_flags(ctx) | LOOKUP_FLAG_DIRECTORY_OK, &dentry, <e, NULL); - if (ret != 0) + if (ret) return ret; return inode_to_stbuf(dentry->d_inode, lte, stbuf); } -#ifdef ENABLE_XATTR -/* Read an alternate data stream through the XATTR interface, or get its size */ +static int +copy_xattr(char *dest, size_t destsize, const void *src, size_t srcsize) +{ + if (!destsize) + return srcsize; + if (destsize < srcsize) + return -ERANGE; + memcpy(dest, src, srcsize); + return srcsize; +} + static int wimfs_getxattr(const char *path, const char *name, char *value, size_t size) { - int ret; + struct fuse_context *fuse_ctx = fuse_get_context(); + const struct wimfs_context *ctx = WIMFS_CTX(fuse_ctx); struct wim_inode *inode; struct wim_ads_entry *ads_entry; - u64 stream_size; struct wim_lookup_table_entry *lte; - struct wimfs_context *ctx = wimfs_get_context(); + + if (!strncmp(name, "wimfs.", 6)) { + /* Handle some magical extended attributes. These really should + * be ioctls, but directory ioctls aren't supported until + * libfuse 2.9, and even then they are broken. */ + name += 6; + if (!strcmp(name, "wim_filename")) { + return copy_xattr(value, size, ctx->wim->filename, + strlen(ctx->wim->filename)); + } + if (!strcmp(name, "wim_info")) { + struct wimlib_wim_info info; + + wimlib_get_wim_info(ctx->wim, &info); + + return copy_xattr(value, size, &info, sizeof(info)); + } + if (!strcmp(name, "mounted_image")) { + return copy_xattr(value, size, + &ctx->wim->current_image, sizeof(int)); + } + if (!strcmp(name, "mount_flags")) { + return copy_xattr(value, size, + &ctx->mount_flags, sizeof(int)); + } + if (!strcmp(name, "unmount")) { + struct wimfs_unmount_info info; + memset(&info, 0, sizeof(info)); + return unmount_wimfs(&info); + } + return -ENOATTR; + } if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; - if (strlen(name) <= 5 || memcmp(name, "user.", 5) != 0) + if (strncmp(name, "user.", 5)) return -ENOATTR; name += 5; + /* Querying a named data stream */ + inode = wim_pathname_to_inode(ctx->wim, path); if (!inode) return -errno; - ads_entry = inode_get_ads_entry(inode, name, NULL); + ads_entry = inode_get_ads_entry(inode, name); if (!ads_entry) - return -ENOATTR; + return (errno == ENOENT) ? -ENOATTR : -errno; lte = ads_entry->lte; - stream_size = lte->size; + if (!lte) + return 0; - if (size == 0) - return stream_size; + if (unlikely(lte->size > INT_MAX)) + return -EFBIG; - if (stream_size > size) - return -ERANGE; + if (size) { + if (lte->size > size) + return -ERANGE; - ret = read_full_stream_into_buf(lte, value); - if (ret) { - if (errno) + if (read_full_stream_into_buf(lte, value)) return -errno; - else - return -EIO; } - return stream_size; + return lte->size; } -#endif -/* Create a hard link */ static int -wimfs_link(const char *to, const char *from) +wimfs_link(const char *existing_path, const char *new_path) { - struct wim_dentry *from_dentry, *from_dentry_parent; - const char *link_name; - struct wim_inode *inode; WIMStruct *wim = wimfs_get_WIMStruct(); - int ret; + const char *new_name; + struct wim_inode *inode; + struct wim_dentry *dir; + struct wim_dentry *new_alias; - inode = wim_pathname_to_inode(wim, to); + inode = wim_pathname_to_inode(wim, existing_path); if (!inode) return -errno; @@ -1814,149 +1306,156 @@ wimfs_link(const char *to, const char *from) FILE_ATTRIBUTE_REPARSE_POINT)) return -EPERM; - from_dentry_parent = get_parent_dentry(wim, from, WIMLIB_CASE_SENSITIVE); - if (!from_dentry_parent) + new_name = path_basename(new_path); + + dir = get_parent_dentry(wim, new_path, WIMLIB_CASE_SENSITIVE); + if (!dir) return -errno; - if (!dentry_is_directory(from_dentry_parent)) + + if (!dentry_is_directory(dir)) return -ENOTDIR; - link_name = path_basename(from); - if (get_dentry_child_with_name(from_dentry_parent, link_name, - WIMLIB_CASE_SENSITIVE)) + if (get_dentry_child_with_name(dir, new_name, WIMLIB_CASE_SENSITIVE)) return -EEXIST; - ret = new_dentry(link_name, &from_dentry); - if (ret) + if (new_dentry(new_name, &new_alias)) return -ENOMEM; + new_alias->d_inode = inode; + inode_add_dentry(new_alias, inode); + dentry_add_child(dir, new_alias); inode->i_nlink++; inode_ref_streams(inode); - from_dentry->d_inode = inode; - inode_add_dentry(from_dentry, inode); - dentry_add_child(from_dentry_parent, from_dentry); return 0; } -#ifdef ENABLE_XATTR static int wimfs_listxattr(const char *path, char *list, size_t size) { - size_t needed_size; - struct wim_inode *inode; - struct wimfs_context *ctx = wimfs_get_context(); - u16 i; - char *p; - bool size_only = (size == 0); + const struct wimfs_context *ctx = wimfs_get_context(); + const struct wim_inode *inode; + char *p = list; + char *end = list + size; + int total_size = 0; if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; - /* List alternate data streams, or get the list size */ + /* List named data streams, or get the list size. We report each named + * data stream "X" as an extended attribute "user.X". */ inode = wim_pathname_to_inode(ctx->wim, path); if (!inode) return -errno; - p = list; - for (i = 0; i < inode->i_num_ads; i++) { - - if (!ads_entry_is_named_stream(&inode->i_ads_entries[i])) - continue; - + for (u16 i = 0; i < inode->i_num_ads; i++) { + const struct wim_ads_entry *entry; char *stream_name_mbs; size_t stream_name_mbs_nbytes; - int ret; - ret = utf16le_to_tstr(inode->i_ads_entries[i].stream_name, - inode->i_ads_entries[i].stream_name_nbytes, - &stream_name_mbs, - &stream_name_mbs_nbytes); - if (ret) + entry = &inode->i_ads_entries[i]; + + if (!entry->stream_name_nbytes) + continue; + + if (utf16le_to_tstr(entry->stream_name, + entry->stream_name_nbytes, + &stream_name_mbs, + &stream_name_mbs_nbytes)) return -errno; - needed_size = stream_name_mbs_nbytes + 6; - if (!size_only) { - if (needed_size > size) { + if (unlikely(INT_MAX - total_size < stream_name_mbs_nbytes + 6)) { + FREE(stream_name_mbs); + return -EFBIG; + } + + total_size += stream_name_mbs_nbytes + 6; + if (size) { + if (end - p < stream_name_mbs_nbytes + 6) { FREE(stream_name_mbs); return -ERANGE; } - sprintf(p, "user.%s", stream_name_mbs); - size -= needed_size; + p = mempcpy(p, "user.", 5); + p = mempcpy(p, stream_name_mbs, stream_name_mbs_nbytes); + *p++ = '\0'; } - p += needed_size; FREE(stream_name_mbs); } - return p - list; + return total_size; } -#endif - -/* Create a directory in the WIM image. */ static int wimfs_mkdir(const char *path, mode_t mode) { + /* Note: according to fuse.h, mode may not include S_IFDIR */ return create_dentry(fuse_get_context(), path, mode | S_IFDIR, 0, FILE_ATTRIBUTE_DIRECTORY, NULL); } -/* Create a non-directory, non-symbolic-link file or alternate data stream in - * the WIM image. */ static int wimfs_mknod(const char *path, mode_t mode, dev_t rdev) { - const char *stream_name; struct fuse_context *fuse_ctx = fuse_get_context(); struct wimfs_context *wimfs_ctx = WIMFS_CTX(fuse_ctx); + const char *stream_name; if ((wimfs_ctx->mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS) - && (stream_name = path_stream_name(path))) { + && (stream_name = path_stream_name(path))) + { + struct wim_ads_entry *old_entry; + struct wim_ads_entry *new_entry; + struct wim_inode *inode; + char *p; + + /* Create a named data stream. */ if (!S_ISREG(mode)) - return -EPERM; + return -EOPNOTSUPP; - /* Make an alternate data stream */ - struct wim_ads_entry *new_entry; - struct wim_inode *inode; + p = (char *)stream_name - 1; - char *p = (char*)stream_name - 1; - wimlib_assert(*p == ':'); *p = '\0'; - inode = wim_pathname_to_inode(wimfs_ctx->wim, path); + *p = ':'; if (!inode) return -errno; - if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) - return -ENOENT; - if (inode_get_ads_entry(inode, stream_name, NULL)) + + old_entry = inode_get_ads_entry(inode, stream_name); + if (old_entry) return -EEXIST; + if (errno != ENOENT) + return -errno; + new_entry = inode_add_ads(inode, stream_name); if (!new_entry) - return -ENOMEM; + return -errno; return 0; } else { + /* Create a regular file, device node, named pipe, or socket. + */ + if (!S_ISREG(mode) && !(wimfs_ctx->mount_flags & WIMLIB_MOUNT_FLAG_UNIX_DATA)) return -EPERM; - /* Make a regular file, device node, named pipe, or socket. */ + /* Note: we still use FILE_ATTRIBUTE_NORMAL for device nodes, + * named pipes, and sockets. The real mode is in the UNIX + * metadata. */ return create_dentry(fuse_ctx, path, mode, rdev, FILE_ATTRIBUTE_NORMAL, NULL); } } -/* Open a file. */ static int wimfs_open(const char *path, struct fuse_file_info *fi) { + struct wimfs_context *ctx = wimfs_get_context(); struct wim_dentry *dentry; - struct wim_lookup_table_entry *lte; - int ret; - struct wimfs_fd *fd; struct wim_inode *inode; + struct wim_lookup_table_entry *lte; u16 stream_idx; - u32 stream_id; - struct wimfs_context *ctx = wimfs_get_context(); - struct wim_lookup_table_entry **back_ptr; + struct wimfs_fd *fd; + int ret; ret = wim_pathname_to_stream(ctx->wim, path, get_lookup_flags(ctx), &dentry, <e, &stream_idx); @@ -1965,59 +1464,51 @@ wimfs_open(const char *path, struct fuse_file_info *fi) inode = dentry->d_inode; - if (stream_idx == 0) { - stream_id = 0; - back_ptr = &inode->i_lte; - } else { - stream_id = inode->i_ads_entries[stream_idx - 1].stream_id; - back_ptr = &inode->i_ads_entries[stream_idx - 1].lte; - } - /* The file resource may be in the staging directory (read-write mounts * only) or in the WIM. If it's in the staging directory, we need to * open a native file descriptor for the corresponding file. Otherwise, * we can read the file resource directly from the WIM file if we are * opening it read-only, but we need to extract the resource to the - * staging directory if we are opening it writable. */ + * staging directory if we are opening it writable. */ if (flags_writable(fi->flags) && (!lte || lte->resource_location != RESOURCE_IN_STAGING_FILE)) { - u64 size = (lte) ? lte->size : 0; - ret = extract_resource_to_staging_dir(inode, stream_id, - <e, size, ctx); + ret = extract_resource_to_staging_dir(inode, + stream_idx, + <e, + lte ? lte->size : 0, + ctx); if (ret) return ret; - *back_ptr = lte; } - ret = alloc_wimfs_fd(inode, stream_id, lte, &fd); + ret = alloc_wimfs_fd(inode, inode_stream_idx_to_id(inode, stream_idx), + lte, &fd); if (ret) return ret; if (lte && lte->resource_location == RESOURCE_IN_STAGING_FILE) { int raw_fd; - raw_fd = open(lte->staging_file_name, fi->flags); + raw_fd = openat(lte->staging_dir_fd, lte->staging_file_name, + (fi->flags & O_ACCMODE) | O_NOFOLLOW); if (raw_fd < 0) { - int errno_save = errno; close_wimfs_fd(fd); - return -errno_save; + return -errno; } - filedes_init(&fd->staging_fd, raw_fd); + filedes_init(&fd->f_staging_fd, raw_fd); } fi->fh = (uintptr_t)fd; return 0; } -/* Opens a directory. */ static int wimfs_opendir(const char *path, struct fuse_file_info *fi) { + WIMStruct *wim = wimfs_get_WIMStruct(); struct wim_inode *inode; + struct wimfs_fd *fd; int ret; - struct wimfs_fd *fd = NULL; - struct wimfs_context *ctx = wimfs_get_context(); - WIMStruct *wim = ctx->wim; inode = wim_pathname_to_inode(wim, path); if (!inode) @@ -2025,79 +1516,65 @@ wimfs_opendir(const char *path, struct fuse_file_info *fi) if (!inode_is_directory(inode)) return -ENOTDIR; ret = alloc_wimfs_fd(inode, 0, NULL, &fd); + if (ret) + return ret; fi->fh = (uintptr_t)fd; - return ret; + return 0; } - -/* - * Read data from a file in the WIM or in the staging directory. - */ static int wimfs_read(const char *path, char *buf, size_t size, off_t offset, struct fuse_file_info *fi) { - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; + struct wimfs_fd *fd = WIMFS_FD(fi); + const struct wim_lookup_table_entry *lte; ssize_t ret; - u64 stream_size; - if (!fd) - return -EBADF; - - if (size == 0) + lte = fd->f_lte; + if (!lte) return 0; - if (fd->f_lte) - stream_size = fd->f_lte->size; - else - stream_size = 0; + if (offset >= lte->size) + return 0; - if (offset > stream_size) - return -EOVERFLOW; + if (size > lte->size - offset) + size = lte->size - offset; - size = min(size, stream_size - offset); - if (size == 0) + if (!size) return 0; - switch (fd->f_lte->resource_location) { - case RESOURCE_IN_STAGING_FILE: - ret = raw_pread(&fd->staging_fd, buf, size, offset); - if (ret == -1) - ret = -errno; - break; + switch (lte->resource_location) { case RESOURCE_IN_WIM: - if (read_partial_wim_stream_into_buf(fd->f_lte, size, - offset, buf)) - ret = errno ? -errno : -EIO; + if (read_partial_wim_stream_into_buf(lte, size, offset, buf)) + ret = -errno; else ret = size; break; + case RESOURCE_IN_STAGING_FILE: + ret = raw_pread(&fd->f_staging_fd, buf, size, offset); + if (ret < 0) + ret = -errno; + break; case RESOURCE_IN_ATTACHED_BUFFER: - memcpy(buf, fd->f_lte->attached_buffer + offset, size); + memcpy(buf, lte->attached_buffer + offset, size); ret = size; break; default: - ERROR("Invalid resource location"); - ret = -EIO; + ret = -EINVAL; break; } return ret; } -/* Fills in the entries of the directory specified by @path using the - * FUSE-provided function @filler. */ static int wimfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, struct fuse_file_info *fi) { - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; - struct wim_inode *inode; - struct wim_dentry *child; + struct wimfs_fd *fd = WIMFS_FD(fi); + const struct wim_inode *inode; + const struct wim_dentry *child; int ret; - if (!fd) - return -EBADF; - inode = fd->f_inode; ret = filler(buf, ".", NULL, 0); @@ -2126,13 +1603,14 @@ wimfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler, return 0; } - static int wimfs_readlink(const char *path, char *buf, size_t buf_len) { - struct wimfs_context *ctx = wimfs_get_context(); - struct wim_inode *inode = wim_pathname_to_inode(ctx->wim, path); - int ret; + WIMStruct *wim = wimfs_get_WIMStruct(); + const struct wim_inode *inode; + ssize_t ret; + + inode = wim_pathname_to_inode(wim, path); if (!inode) return -errno; if (!inode_is_symlink(inode)) @@ -2141,7 +1619,6 @@ wimfs_readlink(const char *path, char *buf, size_t buf_len) return -EINVAL; ret = wim_inode_readlink(inode, buf, buf_len - 1, NULL); if (ret >= 0) { - wimlib_assert(ret <= buf_len - 1); buf[ret] = '\0'; ret = 0; } else if (ret == -ENAMETOOLONG) { @@ -2150,52 +1627,42 @@ wimfs_readlink(const char *path, char *buf, size_t buf_len) return ret; } -/* Close a file. */ +/* We use this for both release() and releasedir(), since in both cases we + * simply need to close the file descriptor. */ static int wimfs_release(const char *path, struct fuse_file_info *fi) { - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; - return close_wimfs_fd(fd); -} - -/* Close a directory */ -static int -wimfs_releasedir(const char *path, struct fuse_file_info *fi) -{ - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; - return close_wimfs_fd(fd); + return close_wimfs_fd(WIMFS_FD(fi)); } -#ifdef ENABLE_XATTR -/* Remove an alternate data stream through the XATTR interface */ static int wimfs_removexattr(const char *path, const char *name) { + struct wimfs_context *ctx = wimfs_get_context(); struct wim_inode *inode; struct wim_ads_entry *ads_entry; - u16 ads_idx; - struct wimfs_context *ctx = wimfs_get_context(); if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; - if (strlen(name) < 5 || memcmp(name, "user.", 5) != 0) + if (strncmp(name, "user.", 5)) return -ENOATTR; name += 5; + /* Removing a named data stream. */ + inode = wim_pathname_to_inode(ctx->wim, path); if (!inode) return -errno; - ads_entry = inode_get_ads_entry(inode, name, &ads_idx); + ads_entry = inode_get_ads_entry(inode, name); if (!ads_entry) - return -ENOATTR; - inode_remove_ads(inode, ads_idx, ctx->wim->lookup_table); + return (errno == ENOENT) ? -ENOATTR : -errno; + + inode_remove_ads(inode, ads_entry, ctx->wim->lookup_table); return 0; } -#endif -/* Renames a file or directory. See rename (3) */ static int wimfs_rename(const char *from, const char *to) { @@ -2203,12 +1670,11 @@ wimfs_rename(const char *from, const char *to) WIMLIB_CASE_SENSITIVE, NULL); } -/* Remove a directory */ static int wimfs_rmdir(const char *path) { - struct wim_dentry *dentry; WIMStruct *wim = wimfs_get_WIMStruct(); + struct wim_dentry *dentry; dentry = get_dentry(wim, path, WIMLIB_CASE_SENSITIVE); if (!dentry) @@ -2224,49 +1690,58 @@ wimfs_rmdir(const char *path) return 0; } -#ifdef ENABLE_XATTR -/* Write an alternate data stream through the XATTR interface */ static int wimfs_setxattr(const char *path, const char *name, const char *value, size_t size, int flags) { - struct wim_ads_entry *existing_ads_entry; - struct wim_inode *inode; - u16 ads_idx; struct wimfs_context *ctx = wimfs_get_context(); - int ret; + struct wim_inode *inode; + struct wim_ads_entry *existing_entry; + + if (!strncmp(name, "wimfs.", 6)) { + /* Handle some magical extended attributes. These really should + * be ioctls, but directory ioctls aren't supported until + * libfuse 2.9, and even then they are broken. */ + name += 6; + if (!strcmp(name, "unmount")) { + if (size < sizeof(struct wimfs_unmount_info)) + return -EINVAL; + return unmount_wimfs((const void *)value); + } + return -ENOATTR; + } if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; - if (strlen(name) <= 5 || memcmp(name, "user.", 5) != 0) + if (strncmp(name, "user.", 5)) return -ENOATTR; name += 5; + /* Setting the contents of a named data stream. */ + inode = wim_pathname_to_inode(ctx->wim, path); if (!inode) return -errno; - existing_ads_entry = inode_get_ads_entry(inode, name, &ads_idx); - if (existing_ads_entry) { + existing_entry = inode_get_ads_entry(inode, name); + if (existing_entry) { if (flags & XATTR_CREATE) return -EEXIST; } else { + if (errno != ENOENT) + return -errno; if (flags & XATTR_REPLACE) return -ENOATTR; } - ret = inode_add_ads_with_data(inode, name, value, - size, ctx->wim->lookup_table); - if (ret == 0) { - if (existing_ads_entry) - inode_remove_ads(inode, ads_idx, ctx->wim->lookup_table); - } else { - ret = -ENOMEM; - } - return ret; + if (!inode_add_ads_with_data(inode, name, value, + size, ctx->wim->lookup_table)) + return -errno; + if (existing_entry) + inode_remove_ads(inode, existing_entry, ctx->wim->lookup_table); + return 0; } -#endif static int wimfs_symlink(const char *to, const char *from) @@ -2278,89 +1753,77 @@ wimfs_symlink(const char *to, const char *from) ret = create_dentry(fuse_ctx, from, S_IFLNK | 0777, 0, FILE_ATTRIBUTE_REPARSE_POINT, &dentry); - if (ret == 0) { - dentry->d_inode->i_reparse_tag = WIM_IO_REPARSE_TAG_SYMLINK; - ret = wim_inode_set_symlink(dentry->d_inode, to, - wimfs_ctx->wim->lookup_table); - if (ret) { - remove_dentry(dentry, wimfs_ctx->wim->lookup_table); - if (ret == WIMLIB_ERR_NOMEM) - ret = -ENOMEM; - else - ret = -EIO; - } + if (ret) + return ret; + dentry->d_inode->i_reparse_tag = WIM_IO_REPARSE_TAG_SYMLINK; + ret = wim_inode_set_symlink(dentry->d_inode, to, + wimfs_ctx->wim->lookup_table); + if (ret) { + remove_dentry(dentry, wimfs_ctx->wim->lookup_table); + if (ret == WIMLIB_ERR_NOMEM) + ret = -ENOMEM; + else + ret = -EINVAL; } return ret; } - -/* Reduce the size of a file */ static int wimfs_truncate(const char *path, off_t size) { + const struct wimfs_context *ctx = wimfs_get_context(); struct wim_dentry *dentry; struct wim_lookup_table_entry *lte; - int ret; u16 stream_idx; - u32 stream_id; - struct wim_inode *inode; - struct wimfs_context *ctx = wimfs_get_context(); + int ret; + int fd; ret = wim_pathname_to_stream(ctx->wim, path, get_lookup_flags(ctx), &dentry, <e, &stream_idx); - if (ret != 0) + if (ret) return ret; - if (lte == NULL && size == 0) + if (!lte && !size) return 0; - if (lte != NULL && lte->resource_location == RESOURCE_IN_STAGING_FILE) { - ret = truncate(lte->staging_file_name, size); - if (ret) - ret = -errno; - else - lte->size = size; - } else { - /* File in WIM. Extract it to the staging directory, but only - * the first @size bytes of it. */ - struct wim_lookup_table_entry **back_ptr; - - inode = dentry->d_inode; - if (stream_idx == 0) { - stream_id = 0; - back_ptr = &inode->i_lte; - } else { - stream_id = inode->i_ads_entries[stream_idx - 1].stream_id; - back_ptr = &inode->i_ads_entries[stream_idx - 1].lte; - } - ret = extract_resource_to_staging_dir(inode, stream_id, - <e, size, ctx); - *back_ptr = lte; + if (!lte || lte->resource_location != RESOURCE_IN_STAGING_FILE) { + return extract_resource_to_staging_dir(dentry->d_inode, + stream_idx, <e, + size, ctx); } - return ret; + + /* Truncate the staging file. */ + fd = openat(lte->staging_dir_fd, lte->staging_file_name, + O_WRONLY | O_NOFOLLOW); + if (fd < 0) + return -errno; + ret = ftruncate(fd, size); + if (close(fd) || ret) + return -errno; + lte->size = size; + return 0; } -/* Unlink a non-directory or alternate data stream */ static int wimfs_unlink(const char *path) { + const struct wimfs_context *ctx = wimfs_get_context(); struct wim_dentry *dentry; - struct wim_lookup_table_entry *lte; - int ret; u16 stream_idx; - struct wimfs_context *ctx = wimfs_get_context(); + int ret; ret = wim_pathname_to_stream(ctx->wim, path, get_lookup_flags(ctx), - &dentry, <e, &stream_idx); + &dentry, NULL, &stream_idx); - if (ret != 0) + if (ret) return ret; if (inode_stream_name_nbytes(dentry->d_inode, stream_idx) == 0) remove_dentry(dentry, ctx->wim->lookup_table); else - inode_remove_ads(dentry->d_inode, stream_idx - 1, + inode_remove_ads(dentry->d_inode, + &dentry->d_inode->i_ads_entries[stream_idx - 1], ctx->wim->lookup_table); return 0; } @@ -2374,8 +1837,8 @@ wimfs_unlink(const char *path) static int wimfs_utimens(const char *path, const struct timespec tv[2]) { - struct wim_inode *inode; WIMStruct *wim = wimfs_get_WIMStruct(); + struct wim_inode *inode; inode = wim_pathname_to_inode(wim, path); if (!inode) @@ -2399,50 +1862,33 @@ wimfs_utimens(const char *path, const struct timespec tv[2]) static int wimfs_utime(const char *path, struct utimbuf *times) { - struct wim_inode *inode; WIMStruct *wim = wimfs_get_WIMStruct(); + struct wim_inode *inode; inode = wim_pathname_to_inode(wim, path); if (!inode) return -errno; - inode->i_last_write_time = unix_timestamp_to_wim(times->modtime); inode->i_last_access_time = unix_timestamp_to_wim(times->actime); + inode->i_last_write_time = unix_timestamp_to_wim(times->modtime); return 0; } #endif /* !HAVE_UTIMENSAT */ -/* Writes to a file in the WIM filesystem. - * It may be an alternate data stream, but here we don't even notice because we - * just get a lookup table entry. */ static int wimfs_write(const char *path, const char *buf, size_t size, off_t offset, struct fuse_file_info *fi) { - struct wimfs_fd *fd = (struct wimfs_fd*)(uintptr_t)fi->fh; - int ret; - - if (!fd) - return -EBADF; - - wimlib_assert(fd->f_lte != NULL); - wimlib_assert(fd->f_lte->staging_file_name != NULL); - wimlib_assert(filedes_valid(&fd->staging_fd)); - wimlib_assert(fd->f_inode != NULL); + struct wimfs_fd *fd = WIMFS_FD(fi); + ssize_t ret; - /* Write the data. */ - ret = raw_pwrite(&fd->staging_fd, buf, size, offset); - if (ret == -1) + ret = raw_pwrite(&fd->f_staging_fd, buf, size, offset); + if (ret < 0) return -errno; - /* Update file size */ - if (offset + size > fd->f_lte->size) { - DEBUG("Update file size %"PRIu64 " => %"PRIu64"", - fd->f_lte->size, offset + size); + if (offset + size > fd->f_lte->size) fd->f_lte->size = offset + size; - } - /* Update timestamps */ touch_inode(fd->f_inode); return ret; } @@ -2450,17 +1896,12 @@ wimfs_write(const char *path, const char *buf, size_t size, static struct fuse_operations wimfs_operations = { .chmod = wimfs_chmod, .chown = wimfs_chown, - .destroy = wimfs_destroy, .fgetattr = wimfs_fgetattr, .ftruncate = wimfs_ftruncate, .getattr = wimfs_getattr, -#ifdef ENABLE_XATTR .getxattr = wimfs_getxattr, -#endif .link = wimfs_link, -#ifdef ENABLE_XATTR .listxattr = wimfs_listxattr, -#endif .mkdir = wimfs_mkdir, .mknod = wimfs_mknod, .open = wimfs_open, @@ -2469,15 +1910,11 @@ static struct fuse_operations wimfs_operations = { .readdir = wimfs_readdir, .readlink = wimfs_readlink, .release = wimfs_release, - .releasedir = wimfs_releasedir, -#ifdef ENABLE_XATTR + .releasedir = wimfs_release, .removexattr = wimfs_removexattr, -#endif .rename = wimfs_rename, .rmdir = wimfs_rmdir, -#ifdef ENABLE_XATTR .setxattr = wimfs_setxattr, -#endif .symlink = wimfs_symlink, .truncate = wimfs_truncate, .unlink = wimfs_unlink, @@ -2488,9 +1925,9 @@ static struct fuse_operations wimfs_operations = { #endif .write = wimfs_write, - /* wimfs keeps file descriptor structures (struct wimfs_fd), so there is - * no need to have the file path provided on operations such as read() - * where only the file descriptor is needed. */ + /* We keep track of file descriptor structures (struct wimfs_fd), so + * there is no need to have the file path provided on operations such as + * read(). */ #if FUSE_MAJOR_VERSION > 2 || (FUSE_MAJOR_VERSION == 2 && FUSE_MINOR_VERSION >= 8) .flag_nullpath_ok = 1, #endif @@ -2500,24 +1937,18 @@ static struct fuse_operations wimfs_operations = { #endif }; - /* API function documented in wimlib.h */ WIMLIBAPI int wimlib_mount_image(WIMStruct *wim, int image, const char *dir, int mount_flags, const char *staging_dir) { - int argc; - char *argv[16]; int ret; - char *dir_copy; struct wim_image_metadata *imd; struct wimfs_context ctx; - struct wim_inode *inode; + char *fuse_argv[16]; + int fuse_argc; - DEBUG("Mount: wim = %p, image = %d, dir = %s, flags = %d, ", - wim, image, dir, mount_flags); - - if (!wim || !dir) + if (!wim || !dir || !*dir) return WIMLIB_ERR_INVALID_PARAM; if (mount_flags & ~(WIMLIB_MOUNT_FLAG_READWRITE | @@ -2529,247 +1960,423 @@ wimlib_mount_image(WIMStruct *wim, int image, const char *dir, WIMLIB_MOUNT_FLAG_ALLOW_OTHER)) return WIMLIB_ERR_INVALID_PARAM; + /* For read-write mount, check for write access to the WIM. */ if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { ret = can_delete_from_wim(wim); if (ret) return ret; } + /* Select the image to mount. */ ret = select_wim_image(wim, image); if (ret) return ret; - DEBUG("Selected image %d", image); - + /* Get the metadata for the image to mount. */ imd = wim_get_current_image_metadata(wim); if (imd->modified) { - /* wimfs_read() only supports a limited number of stream - * locations, not including RESOURCE_IN_FILE_ON_DISK, - * RESOURCE_IN_NTFS_VOLUME, etc. that might appear if files were - * added to the WIM image. */ - ERROR("Cannot mount an image with newly added files!"); + /* To avoid complicating things, we don't support mounting + * images to which in-memory modifications have already been + * made. */ + ERROR("Cannot mount a modified WIM image!"); return WIMLIB_ERR_INVALID_PARAM; } - if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { - ret = lock_wim(wim, wim->in_fd.fd); - if (ret) - return ret; - } + ret = lock_wim_for_append(wim, wim->in_fd.fd); + if (ret) + return ret; - /* Use default stream interface if one was not specified */ + /* If the user did not specify an interface for accessing named + * data streams, use the default (extended attributes). */ if (!(mount_flags & (WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_NONE | - WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR | - WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS))) + WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR | + WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS))) mount_flags |= WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR; - DEBUG("Initializing struct wimfs_context"); - init_wimfs_context(&ctx); + /* Start initializing the wimfs_context. */ + memset(&ctx, 0, sizeof(struct wimfs_context)); ctx.wim = wim; ctx.mount_flags = mount_flags; - ctx.image_inode_list = &imd->inode_list; - ctx.default_uid = getuid(); - ctx.default_gid = getgid(); - wimlib_assert(list_empty(&imd->unhashed_streams)); if (mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS) ctx.default_lookup_flags = LOOKUP_FLAG_ADS_OK; + /* For read-write mount, create the staging directory. */ + if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { + ret = make_staging_dir(&ctx, staging_dir); + if (ret) + goto out_unlock; + } + ctx.owner_uid = getuid(); + ctx.owner_gid = getgid(); - DEBUG("Unlinking message queues in case they already exist"); - ret = set_message_queue_names(&ctx, dir); - if (ret) - goto out_unlock; - unlink_message_queues(&ctx); + /* Add each stream referenced by files in the image to a list and + * preemptively double the number of references to each. The latter is + * done to allow implementing the WIMLIB_UNMOUNT_FLAG_NEW_IMAGE + * semantics. */ + INIT_LIST_HEAD(&ctx.orig_stream_list); + if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { + unsigned i; + struct wim_inode *inode; + struct wim_lookup_table_entry *lte; - DEBUG("Preparing arguments to fuse_main()"); + image_for_each_inode(inode, imd) { + for (i = 0; i <= inode->i_num_ads; i++) { + lte = inode_stream_lte(inode, i, + wim->lookup_table); + if (lte) + lte->out_refcnt = 0; + } + } - dir_copy = STRDUP(dir); - if (!dir_copy) { - ret = WIMLIB_ERR_NOMEM; - goto out_free_message_queue_names; + image_for_each_inode(inode, imd) { + for (i = 0; i <= inode->i_num_ads; i++) { + lte = inode_stream_lte(inode, i, + wim->lookup_table); + if (lte) { + if (lte->out_refcnt == 0) + list_add(<e->orig_stream_list, + &ctx.orig_stream_list); + lte->out_refcnt += inode->i_nlink; + lte->refcnt += inode->i_nlink; + } + } + } } - argc = 0; - argv[argc++] = "wimlib"; - argv[argc++] = dir_copy; + /* Assign new inode numbers. */ + reassign_inode_numbers(&ctx); + + /* If a read-write mount, mark the image as modified. */ + if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) + imd->modified = 1; + + /* Build the FUSE command line. */ - /* disable multi-threaded operation */ - argv[argc++] = "-s"; + fuse_argc = 0; + fuse_argv[fuse_argc++] = "wimlib"; + fuse_argv[fuse_argc++] = (char *)dir; + /* Disable multi-threaded operation. */ + fuse_argv[fuse_argc++] = "-s"; + + /* Enable FUSE debug mode (don't fork) if requested by the user. */ if (mount_flags & WIMLIB_MOUNT_FLAG_DEBUG) - argv[argc++] = "-d"; + fuse_argv[fuse_argc++] = "-d"; /* - * We provide the use_ino option to the FUSE mount because we are going - * to assign inode numbers ourselves. */ + * Build the FUSE mount options: + * + * use_ino + * FUSE will use the inode numbers we provide. We want this, + * because we have inodes and will number them ourselves. + * + * subtype=wimfs + * Name for our filesystem (main type is "fuse"). + * + * hard_remove + * If an open file is unlinked, unlink it for real rather than + * renaming it to a hidden file. Our code supports this; an + * unlinked inode is retained until all its file descriptors have + * been closed. + * + * default_permissions + * FUSE will perform permission checking. Useful when + * WIMLIB_MOUNT_FLAG_UNIX_DATA is provided and the WIM image + * contains the UNIX permissions for each file. + * + * kernel_cache + * Cache the contents of files. This will speed up repeated access + * to files on a mounted WIM image, since they won't need to be + * decompressed repeatedly. This option is valid because data in + * the WIM image should never be changed externally. (Although, if + * someone really wanted to they could modify the WIM file or mess + * with the staging directory; but then they're asking for + * trouble.) + * + * entry_timeout=1000000000 + * Cache positive name lookups indefinitely, since names can only + * be added, removed, or modified through the mounted filesystem + * itself. + * + * negative_timeout=1000000000 + * Cache negative name lookups indefinitely, since names can only + * be added, removed, or modified through the mounted filesystem + * itself. + * + * attr_timeout=0 + * Don't cache file/directory attributes. This is needed as a + * workaround for the fact that when caching attributes, the high + * level interface to libfuse considers a file which has several + * hard-linked names as several different files. (Otherwise, we + * could cache our file/directory attributes indefinitely, since + * they can only be changed through the mounted filesystem itself.) + */ char optstring[256] = "use_ino" ",subtype=wimfs" ",attr_timeout=0" -#if FUSE_MAJOR_VERSION > 2 || (FUSE_MAJOR_VERSION == 2 && FUSE_MINOR_VERSION >= 8) ",hard_remove" -#endif ",default_permissions" + ",kernel_cache" + ",entry_timeout=1000000000" + ",negative_timeout=1000000000" + ",attr_timeout=0" ; - argv[argc++] = "-o"; - argv[argc++] = optstring; - if ((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)) { - /* Read-write mount. Make the staging directory */ - ret = make_staging_dir(&ctx, staging_dir); - if (ret) - goto out_free_dir_copy; - } else { - /* Read-only mount */ + fuse_argv[fuse_argc++] = "-o"; + fuse_argv[fuse_argc++] = optstring; + if (!(mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)) strcat(optstring, ",ro"); - } if (mount_flags & WIMLIB_MOUNT_FLAG_ALLOW_OTHER) strcat(optstring, ",allow_other"); - argv[argc] = NULL; + fuse_argv[fuse_argc] = NULL; -#ifdef ENABLE_DEBUG - { - int i; - DEBUG("FUSE command line (argc = %d): ", argc); - for (i = 0; i < argc; i++) { - fputs(argv[i], stdout); - putchar(' '); + /* Mount our filesystem. */ + ret = fuse_main(fuse_argc, fuse_argv, &wimfs_operations, &ctx); + + /* Cleanup and return. */ + if (ret) + ret = WIMLIB_ERR_FUSE; + release_extra_refcnts(&ctx); + if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) + delete_staging_dir(&ctx); +out_unlock: + unlock_wim_for_append(wim, wim->in_fd.fd); + return ret; +} + +struct commit_progress_thread_args { + mqd_t mq; + wimlib_progress_func_t progfunc; + void *progctx; + int status; +}; + +static void * +commit_progress_thread_proc(void *_args) +{ + struct commit_progress_thread_args *args = _args; + struct commit_progress_report report; + ssize_t ret; + + args->status = WIMLIB_ERR_NOT_A_MOUNTPOINT; + for (;;) { + ret = mq_receive(args->mq, + (char *)&report, sizeof(report), NULL); + if (ret < 0) { + if (errno == EINTR) + continue; + break; + } + if (ret == sizeof(int)) { + args->status = *(int *)&report; + break; } - putchar('\n'); - fflush(stdout); + if (ret < sizeof(report)) + continue; + call_progress(args->progfunc, report.msg, + &report.info, args->progctx); } -#endif + return NULL; +} - /* Assign inode numbers. Also, if a read-write mount was requested, - * mark the dentry tree as modified, and add each stream referenced by - * files in the image to a list and preemptively double the number of - * references to each. The latter is done to allow implementing the - * WIMLIB_UNMOUNT_FLAG_NEW_IMAGE semantics. */ - ctx.next_ino = 1; - INIT_LIST_HEAD(&ctx.orig_stream_list); - if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { - imd->modified = 1; - image_for_each_inode(inode, imd) { - inode->i_ino = ctx.next_ino++; - for (unsigned i = 0; i <= inode->i_num_ads; i++) { - struct wim_lookup_table_entry *lte; +static void +generate_message_queue_name(char name[WIMFS_MQUEUE_NAME_LEN + 1]) +{ + name[0] = '/'; + memcpy(name + 1, "wimfs-", 6); + randomize_char_array_with_alnum(name + 7, WIMFS_MQUEUE_NAME_LEN - 7); + name[WIMFS_MQUEUE_NAME_LEN] = '\0'; +} - lte = inode_stream_lte(inode, i, wim->lookup_table); - if (lte) - lte->out_refcnt = 0; - } - } - image_for_each_inode(inode, imd) { - for (unsigned i = 0; i <= inode->i_num_ads; i++) { - struct wim_lookup_table_entry *lte; +static mqd_t +create_message_queue(const char *name, bool have_progfunc) +{ + bool am_root = (getuid() == 0); + mode_t umask_save = 0; + mode_t mode = 0600; + struct mq_attr attr; + mqd_t mq; - lte = inode_stream_lte(inode, i, - wim->lookup_table); - if (lte) { - if (lte->out_refcnt == 0) - list_add(<e->orig_stream_list, - &ctx.orig_stream_list); - lte->out_refcnt += inode->i_nlink; - lte->refcnt += inode->i_nlink; - } - } + memset(&attr, 0, sizeof(attr)); + attr.mq_maxmsg = 8; + if (have_progfunc) + attr.mq_msgsize = sizeof(struct commit_progress_report); + else + attr.mq_msgsize = sizeof(int); + + if (am_root) { + /* Filesystem mounted as normal user with --allow-other should + * be able to send messages to root user, if they're doing the + * unmount. */ + umask_save = umask(0); + mode = 0666; + } + mq = mq_open(name, O_RDWR | O_CREAT | O_EXCL, mode, &attr); + if (am_root) + umask(umask_save); + return mq; +} + +/* Unmount a read-write mounted WIM image, committing the changes. */ +static int +do_unmount_commit(const char *dir, int unmount_flags, + wimlib_progress_func_t progfunc, void *progctx) +{ + struct wimfs_unmount_info unmount_info; + mqd_t mq; + struct commit_progress_thread_args args; + pthread_t commit_progress_tid; + int ret; + + memset(&unmount_info, 0, sizeof(unmount_info)); + unmount_info.unmount_flags = unmount_flags; + generate_message_queue_name(unmount_info.mq_name); + + mq = create_message_queue(unmount_info.mq_name, progfunc != NULL); + if (mq == (mqd_t)-1) { + ERROR_WITH_ERRNO("Can't create POSIX message queue"); + return WIMLIB_ERR_MQUEUE; + } + + /* The current thread will be stuck in setxattr() until the image is + * committed. Create a thread to handle the progress messages. */ + if (progfunc) { + args.mq = mq; + args.progfunc = progfunc; + args.progctx = progctx; + ret = pthread_create(&commit_progress_tid, NULL, + commit_progress_thread_proc, &args); + if (ret) { + errno = ret; + ERROR_WITH_ERRNO("Can't create thread"); + ret = WIMLIB_ERR_NOMEM; + goto out_delete_mq; } - } else { - image_for_each_inode(inode, imd) - inode->i_ino = ctx.next_ino++; + unmount_info.unmount_flags |= WIMLIB_UNMOUNT_FLAG_SEND_PROGRESS; } - DEBUG("(next_ino = %"PRIu64")", ctx.next_ino); + if (!setxattr(dir, "wimfs.unmount", + (const char *)&unmount_info, sizeof(unmount_info), 0)) + ret = 0; + else if (errno == EACCES || errno == EPERM) + ret = WIMLIB_ERR_NOT_PERMITTED_TO_UNMOUNT; + else + ret = WIMLIB_ERR_NOT_A_MOUNTPOINT; + + if (progfunc) { + /* Terminate the progress thread and retrieve final unmount + * status. */ - DEBUG("Calling fuse_main()"); + int tmp = -1; + mq_send(mq, (const char *)&tmp, sizeof(int), 1); - ret = fuse_main(argc, argv, &wimfs_operations, &ctx); + pthread_join(commit_progress_tid, NULL); + if (!ret && args.status != -1) + ret = args.status; + } else if (!ret) { + /* Retrieve the final unmount status. */ - DEBUG("Returned from fuse_main() (ret = %d)", ret); + int tmp = -1; + int len; - if (ret) { - ret = WIMLIB_ERR_FUSE; - } else { - if (ctx.have_status) - ret = ctx.status; + mq_send(mq, (const char *)&tmp, sizeof(int), 1); + len = mq_receive(mq, (char *)&tmp, sizeof(int), NULL); + + if (len == 4 && tmp != -1) + ret = tmp; else - ret = WIMLIB_ERR_TIMEOUT; - } - if (ctx.daemon_to_unmount_mq != (mqd_t)(-1)) { - send_unmount_finished_msg(ctx.daemon_to_unmount_mq, ret); - close_message_queues(&ctx); + ret = WIMLIB_ERR_NOT_A_MOUNTPOINT; } +out_delete_mq: + mq_close(mq); + mq_unlink(unmount_info.mq_name); + return ret; +} - release_extra_refcnts(&ctx); +/* Unmount a read-only or read-write mounted WIM image, discarding any changes. + */ +static int +do_unmount_discard(const char *dir) +{ + if (!getxattr(dir, "wimfs.unmount", NULL, 0)) + return 0; + else if (errno == EACCES || errno == EPERM) + return WIMLIB_ERR_NOT_PERMITTED_TO_UNMOUNT; + else + return WIMLIB_ERR_NOT_A_MOUNTPOINT; +} - /* Try to delete the staging directory if a deletion wasn't yet - * attempted due to an earlier error */ - if (ctx.staging_dir_name) - delete_staging_dir(&ctx); -out_free_dir_copy: - FREE(dir_copy); -out_unlock: - wim->wim_locked = 0; -out_free_message_queue_names: - free_message_queue_names(&ctx); - return ret; +static int +begin_unmount(const char *dir, int unmount_flags, int *mount_flags_ret, + wimlib_progress_func_t progfunc, void *progctx) +{ + int mount_flags; + int mounted_image; + int wim_filename_len; + union wimlib_progress_info progress; + + if (getxattr(dir, "wimfs.mount_flags", + &mount_flags, sizeof(int)) != sizeof(int)) + return WIMLIB_ERR_NOT_A_MOUNTPOINT; + + *mount_flags_ret = mount_flags; + + if (!progfunc) + return 0; + + if (getxattr(dir, "wimfs.mounted_image", + &mounted_image, sizeof(int)) != sizeof(int)) + return WIMLIB_ERR_NOT_A_MOUNTPOINT; + + wim_filename_len = getxattr(dir, "wimfs.wim_filename", NULL, 0); + if (wim_filename_len < 0) + return WIMLIB_ERR_NOT_A_MOUNTPOINT; + + char wim_filename[wim_filename_len + 1]; + if (getxattr(dir, "wimfs.wim_filename", + wim_filename, wim_filename_len) != wim_filename_len) + return WIMLIB_ERR_NOT_A_MOUNTPOINT; + wim_filename[wim_filename_len] = '\0'; + + progress.unmount.mountpoint = dir; + progress.unmount.mounted_wim = wim_filename; + progress.unmount.mounted_image = mounted_image; + progress.unmount.mount_flags = mount_flags; + progress.unmount.unmount_flags = unmount_flags; + + return call_progress(progfunc, WIMLIB_PROGRESS_MSG_UNMOUNT_BEGIN, + &progress, progctx); } /* API function documented in wimlib.h */ WIMLIBAPI int -wimlib_unmount_image_with_progress(const tchar *dir, int unmount_flags, +wimlib_unmount_image_with_progress(const char *dir, int unmount_flags, wimlib_progress_func_t progfunc, void *progctx) { + int mount_flags; int ret; - struct wimfs_context wimfs_ctx; + + wimlib_global_init(WIMLIB_INIT_FLAG_ASSUME_UTF8); if (unmount_flags & ~(WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY | WIMLIB_UNMOUNT_FLAG_COMMIT | WIMLIB_UNMOUNT_FLAG_REBUILD | WIMLIB_UNMOUNT_FLAG_RECOMPRESS | - WIMLIB_UNMOUNT_FLAG_LAZY | + WIMLIB_UNMOUNT_FLAG_FORCE | WIMLIB_UNMOUNT_FLAG_NEW_IMAGE)) return WIMLIB_ERR_INVALID_PARAM; - init_wimfs_context(&wimfs_ctx); - - ret = set_message_queue_names(&wimfs_ctx, dir); - if (ret != 0) - goto out; - - ret = open_message_queues(&wimfs_ctx, false); - if (ret != 0) - goto out_free_message_queue_names; - - ret = send_unmount_request_msg(wimfs_ctx.unmount_to_daemon_mq, - unmount_flags, - progfunc != NULL); - if (ret != 0) - goto out_close_message_queues; - - ret = execute_fusermount(dir, (unmount_flags & WIMLIB_UNMOUNT_FLAG_LAZY) != 0); - if (ret != 0) - goto out_close_message_queues; - - struct unmount_msg_handler_context handler_ctx = { - .hdr = { - .timeout_seconds = 5, - }, - .daemon_pid = 0, - .progfunc = progfunc, - .progctx = progctx, - }; - - ret = message_loop(wimfs_ctx.daemon_to_unmount_mq, - &unmount_msg_handler_callbacks, - &handler_ctx.hdr); - if (ret == 0) - ret = handler_ctx.status; -out_close_message_queues: - close_message_queues(&wimfs_ctx); -out_free_message_queue_names: - free_message_queue_names(&wimfs_ctx); -out: - return ret; + ret = begin_unmount(dir, unmount_flags, &mount_flags, + progfunc, progctx); + if (ret) + return ret; + + if ((unmount_flags & WIMLIB_UNMOUNT_FLAG_COMMIT) && + (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)) + return do_unmount_commit(dir, unmount_flags, + progfunc, progctx); + else + return do_unmount_discard(dir); } #else /* WITH_FUSE */ @@ -2803,7 +2410,6 @@ wimlib_mount_image(WIMStruct *wim, int image, const tchar *dir, #endif /* !WITH_FUSE */ - WIMLIBAPI int wimlib_unmount_image(const tchar *dir, int unmount_flags) { diff --git a/src/resource.c b/src/resource.c index 7631dd49..5c0225ab 100644 --- a/src/resource.c +++ b/src/resource.c @@ -193,6 +193,7 @@ read_compressed_wim_resource(const struct wim_resource_spec * const rspec, "expected power-of-2 chunk size (got %"PRIu32")", chunk_size); ret = WIMLIB_ERR_INVALID_CHUNK_SIZE; + errno = EINVAL; goto out_free_memory; } @@ -207,8 +208,11 @@ read_compressed_wim_resource(const struct wim_resource_spec * const rspec, } else { ret = wimlib_create_decompressor(ctype, chunk_size, NULL, &decompressor); - if (ret) + if (ret) { + if (ret != WIMLIB_ERR_NOMEM) + errno = EINVAL; goto out_free_memory; + } } const u32 chunk_order = bsr32(chunk_size); @@ -789,6 +793,34 @@ read_file_on_disk_prefix(const struct wim_lookup_table_entry *lte, u64 size, return ret; } +#ifdef WITH_FUSE +static int +read_staging_file_prefix(const struct wim_lookup_table_entry *lte, u64 size, + consume_data_callback_t cb, void *cb_ctx) +{ + int raw_fd; + struct filedes fd; + int ret; + + wimlib_assert(size <= lte->size); + + DEBUG("Reading %"PRIu64" bytes from staging file \"%s\"", + size, lte->staging_file_name); + + raw_fd = openat(lte->staging_dir_fd, lte->staging_file_name, + O_RDONLY | O_NOFOLLOW); + if (raw_fd < 0) { + ERROR_WITH_ERRNO("Can't open staging file \"%s\"", + lte->staging_file_name); + return WIMLIB_ERR_OPEN; + } + filedes_init(&fd, raw_fd); + ret = read_raw_file_data(&fd, 0, size, cb, cb_ctx); + filedes_close(&fd); + return ret; +} +#endif + /* This function handles the trivial case of reading stream data that is, in * fact, already located in an in-memory buffer. */ static int @@ -828,7 +860,7 @@ read_stream_prefix(const struct wim_lookup_table_entry *lte, u64 size, [RESOURCE_IN_FILE_ON_DISK] = read_file_on_disk_prefix, [RESOURCE_IN_ATTACHED_BUFFER] = read_buffer_prefix, #ifdef WITH_FUSE - [RESOURCE_IN_STAGING_FILE] = read_file_on_disk_prefix, + [RESOURCE_IN_STAGING_FILE] = read_staging_file_prefix, #endif #ifdef WITH_NTFS_3G [RESOURCE_IN_NTFS_VOLUME] = read_ntfs_file_prefix, diff --git a/src/util.c b/src/util.c index 7916f40a..f6d3253d 100644 --- a/src/util.c +++ b/src/util.c @@ -352,6 +352,12 @@ static const tchar *error_strings[] = { = T("The user-provided progress function returned an unrecognized value"), [WIMLIB_ERR_MKNOD] = T("Unable to create a special file (e.g. device node or socket)"), + [WIMLIB_ERR_MOUNTED_IMAGE_IS_BUSY] + = T("There are still files open on the mounted WIM image"), + [WIMLIB_ERR_NOT_A_MOUNTPOINT] + = T("There is not a WIM image mounted on the directory"), + [WIMLIB_ERR_NOT_PERMITTED_TO_UNMOUNT] + = T("The current user does not have permission to unmount the WIM image"), }; /* API function documented in wimlib.h */ diff --git a/src/wim.c b/src/wim.c index ff4ac29b..2942863c 100644 --- a/src/wim.c +++ b/src/wim.c @@ -328,8 +328,22 @@ new_image_metadata_array(unsigned num_images) } -/* Load the metadata for the specified WIM image into memory and set it as the - * WIMStruct's currently selected WIM image. */ +/* + * Load the metadata for the specified WIM image into memory and set it + * as the WIMStruct's currently selected image. + * + * @wim + * The WIMStruct for the WIM. + * @image + * The 1-based index of the image in the WIM to select. + * + * On success, 0 will be returned, wim->current_image will be set to + * @image, and wim_get_current_image_metadata() can be used to retrieve + * metadata information for the image. + * + * On failure, WIMLIB_ERR_INVALID_IMAGE, WIMLIB_ERR_METADATA_NOT_FOUND, + * or another error code will be returned. + */ int select_wim_image(WIMStruct *wim, int image) { diff --git a/src/write.c b/src/write.c index 27463d90..0114618f 100644 --- a/src/write.c +++ b/src/write.c @@ -2401,27 +2401,25 @@ finish_write(WIMStruct *wim, int image, int write_flags, #if defined(HAVE_SYS_FILE_H) && defined(HAVE_FLOCK) int -lock_wim(WIMStruct *wim, int fd) +lock_wim_for_append(WIMStruct *wim, int fd) { - int ret = 0; - if (fd != -1 && !wim->wim_locked) { - ret = flock(fd, LOCK_EX | LOCK_NB); - if (ret != 0) { - if (errno == EWOULDBLOCK) { - ERROR("`%"TS"' is already being modified or has been " - "mounted read-write\n" - " by another process!", wim->filename); - ret = WIMLIB_ERR_ALREADY_LOCKED; - } else { - WARNING_WITH_ERRNO("Failed to lock `%"TS"'", - wim->filename); - ret = 0; - } - } else { - wim->wim_locked = 1; - } + if (wim->locked_for_append) + return 0; + if (!flock(fd, LOCK_EX | LOCK_NB)) { + wim->locked_for_append = 1; + return 0; + } + if (errno != EWOULDBLOCK) + return 0; + return WIMLIB_ERR_ALREADY_LOCKED; +} +void +unlock_wim_for_append(WIMStruct *wim, int fd) +{ + if (wim->locked_for_append) { + flock(fd, LOCK_UN); + wim->locked_for_append = 0; } - return ret; } #endif @@ -3062,7 +3060,7 @@ overwrite_wim_inplace(WIMStruct *wim, int write_flags, unsigned num_threads) if (ret) goto out_restore_memory_hdr; - ret = lock_wim(wim, wim->out_fd.fd); + ret = lock_wim_for_append(wim, wim->out_fd.fd); if (ret) goto out_close_wim; @@ -3098,7 +3096,8 @@ overwrite_wim_inplace(WIMStruct *wim, int write_flags, unsigned num_threads) if (ret) goto out_truncate; - wim->wim_locked = 0; + /* lock was dropped when file descriptor was closed */ + wim->locked_for_append = 0; return 0; out_truncate: @@ -3112,7 +3111,8 @@ out_truncate: out_restore_physical_hdr: (void)write_wim_header_flags(hdr_save.flags, &wim->out_fd); out_unlock_wim: - wim->wim_locked = 0; + /* lock is dropped when close_wim_writable() closes the file */ + wim->locked_for_append = 0; out_close_wim: (void)close_wim_writable(wim, write_flags); out_restore_memory_hdr: