*
* After creating or modifying a WIM file, you can write it to a file using
* wimlib_write(). Alternatively, if the WIM was originally read from a file,
- * you can use wimlib_overwrite() to overwrite the original file. In some
- * cases, wimlib_overwrite_xml_and_header() can be used instead.
+ * you can use wimlib_overwrite() to overwrite the original file.
+ *
+ * Please not: merely by calling wimlib_add_image() or many of the other
+ * functions in this library that operate on ::WIMStruct's, you are @b not
+ * modifing the WIM file on disk. Changes are not saved until you explicitly
+ * call wimlib_write() or wimlib_overwrite().
*
* After you are done with the WIM file, use wimlib_free() to free all memory
* associated with a ::WIMStruct and close all files associated with it.
*
- * To see an example of how to use wimlib, see the file
- * @c programs/imagex.c in wimlib's source tree.
+ * To see an example of how to use wimlib, see the file @c programs/imagex.c in
+ * wimlib's source tree.
*
* wimlib supports custom memory allocators; use wimlib_set_memory_allocator()
* for this. However, if wimlib calls into @c libntfs-3g, the custom memory
/** Include an integrity table in the new WIM file. */
#define WIMLIB_WRITE_FLAG_CHECK_INTEGRITY 0x00000001
-/** Print progress information when writing the integrity table. */
+/** Print progress information when writing streams and when writing the
+ * integrity table. */
#define WIMLIB_WRITE_FLAG_SHOW_PROGRESS 0x00000002
/** Print file paths as we write then */
#define WIMLIB_WRITE_FLAG_VERBOSE 0x00000004
+/** Call fsync() when the WIM file is closed */
+#define WIMLIB_WRITE_FLAG_FSYNC 0x00000008
+
+/** Re-build the entire WIM file rather than appending data to it, if possible.
+ * (Applies to wimlib_overwrite(), not wimlib_write()). */
+#define WIMLIB_WRITE_FLAG_REBUILD 0x00000010
+
/** Mark the image being added as the bootable image of the WIM. */
#define WIMLIB_ADD_IMAGE_FLAG_BOOT 0x00000001
/** Follow symlinks; archive and dump the files they point to. */
#define WIMLIB_ADD_IMAGE_FLAG_DEREFERENCE 0x00000004
+/** Show progress information when scanning a directory tree */
+#define WIMLIB_ADD_IMAGE_FLAG_SHOW_PROGRESS 0x00000008
+
/** See documentation for wimlib_export_image(). */
#define WIMLIB_EXPORT_FLAG_BOOT 0x00000001
WIMLIB_ERR_READLINK,
WIMLIB_ERR_READ,
WIMLIB_ERR_RENAME,
+ WIMLIB_ERR_REOPEN,
WIMLIB_ERR_RESOURCE_ORDER,
WIMLIB_ERR_SPECIAL_FILE,
WIMLIB_ERR_SPLIT_INVALID,
* printed as it is scanned or captured. If
* ::WIMLIB_ADD_IMAGE_FLAG_DEREFERENCE is specified, the files or
* directories pointed to by symbolic links are archived rather than the
- * symbolic links themselves.
+ * symbolic links themselves. If ::WIMLIB_ADD_IMAGE_FLAG_SHOW_PROGRESS is
+ * specified, progress information will be printed (distinct from the
+ * verbose information).
*
* @return 0 on success; nonzero on error. On error, changes to @a wim are
* discarded so that it appears to be in the same state as when this function
* was not the case for versions of this library 1.0.3 and earlier.)
*
* wimlib_mount() cannot be used on an image that was exported with
- * wimlib_export() while the dentry trees for both images are still in memory.
+ * wimlib_export_image() while the dentry trees for both images are still in
+ * memory. In addition, wimlib_mount() may not be used to mount an image that
+ * has just been added with wimlib_add_image() or
+ * wimlib_add_image_from_ntfs_volume(), unless the WIM has been written and read
+ * into a new ::WIMStruct.
*
* @param wim
* Pointer to the ::WIMStruct for the WIM file to be mounted.
* @a image does not specify an existing, single image in @a wim.
* @retval ::WIMLIB_ERR_INVALID_PARAM
* @a image is shared among multiple ::WIMStruct's as a result of a call to
- * wimlib_export().
+ * wimlib_export_image(), or @a image has been added with
+ * wimlib_add_image() or wimlib_add_image_from_ntfs_volume().
* @retval ::WIMLIB_ERR_INVALID_RESOURCE_SIZE
* The metadata resource for @a image in @a wim is invalid.
* @retval ::WIMLIB_ERR_INVALID_SECURITY_DATA
* If ::WIMLIB_OPEN_FLAG_SHOW_PROGRESS is given, progress information will
* be shown if the integrity of the WIM is checked.
* If ::WIMLIB_OPEN_FLAG_SPLIT_OK is given, no error will be issued if the
- * WIM is part of a split WIM; otherwise WIMLIB_ERR_SPLIT_UNSUPPORTED is
+ * WIM is part of a split WIM; otherwise ::WIMLIB_ERR_SPLIT_UNSUPPORTED is
* returned. (This flag may be removed in the future, in which case no
* error will be issued when opening a split WIM.)
*
/**
* Overwrites the file that the WIM was originally read from, with changes made.
*
- * The new WIM is written to a temporary file and then renamed to the original
- * file after it is has been completely written. The temporary file currently
- * is made in the same directory as the original WIM file.
- *
- * After this function returns, @a wim must be freed using wimlib_free(). Any
- * further actions on @a wim before doing this are undefined.
+ * There are two ways that a WIM may be overwritten. The first is to do a full
+ * rebuild: the new WIM is written to a temporary file and then renamed to the
+ * original file after it is has been completely written. The temporary file
+ * currently is made in the same directory as the original WIM file. A full
+ * rebuild may take a while, but can be used even if images have been modified
+ * or deleted, will produce a WIM with no holes, and has little chance of
+ * unintentional data loss because the temporary WIM is fsync()ed before being
+ * renamed to the original WIM.
+ *
+ * The second way to overwrite a WIM is by appending to the end of it. This can
+ * be much faster than a full rebuild, but it only works if the only operations
+ * on the WIM have been to change the header or XML data, or to add new images.
+ * Writing a WIM in this mode begins with writing any new file resources *after*
+ * everything in the old WIM, even though this will leave a hole where the old
+ * lookup table, XML data, and integrity were. This is done so that the WIM
+ * remains valid even if the operation is aborted mid-write.
+ *
+ * By default, the overwrite mode is chosen based on the past operations
+ * performed on the WIM. Use the flag ::WIMLIB_WRITE_FLAG_REBUILD to explicitly
+ * request a full rebuild.
+ *
+ * In the temporary-file overwrite mode, no changes are made to the WIM on
+ * failure, and the temporary file is deleted (if possible). Abnormal
+ * termination of the program will result in the temporary file being orphaned.
+ * In the direct append mode, the WIM is truncated to the original length on
+ * failure, while abnormal termination of the program will result in extra data
+ * appended to the original WIM, but it will still be a valid WIM.
*
* @param wim
* Pointer to the ::WIMStruct for the WIM file to write. There may have
* been in-memory changes made to it, which are then reflected in the
* output file.
- * @param flags
+ * @param write_flags
* Bitwise OR of ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY and/or
* ::WIMLIB_WRITE_FLAG_SHOW_PROGRESS.
+ * @param num_threads
+ * Number of threads to use for compression (see wimlib_write()).
*
* @return 0 on success; nonzero on error. This function may return any value
* returned by wimlib_write() as well as the following error codes:
* @retval ::WIMLIB_ERR_RENAME
* The temporary file that the WIM was written to could not be renamed to
* the original filename of @a wim.
+ * @retval ::WIMLIB_ERR_REOPEN
+ * The WIM was overwritten successfully, but it could not be re-opened
+ * read-only. Therefore, the resources in the WIM can no longer be
+ * accessed, so this limits the functions that can be called on @a wim
+ * before calling wimlib_free().
*/
-extern int wimlib_overwrite(WIMStruct *wim, int flags);
+extern int wimlib_overwrite(WIMStruct *wim, int write_flags,
+ unsigned num_threads);
/**
- * Updates the header and XML data of the WIM file, without the need to write
- * out the entire WIM to a temporary file as in wimlib_write().
- *
- * This function must only be used if no files, directories, or images have been
- * added, removed, or changed in the WIM. It must be used when only the boot
- * index or the name or description of image(s) has been changed.
- *
- * After this function returns, @a wim must be freed using wimlib_free(). Any
- * further actions on @a wim before doing this are undefined.
- *
- * @param wim
- * Pointer to the ::WIMStruct for the WIM file to overwrite.
- * @param flags
- * Bitwise OR of ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY and/or
- * ::WIMLIB_WRITE_FLAG_SHOW_PROGRESS.
- *
- * @return 0 on success; nonzero on error.
- *
- * @retval ::WIMLIB_ERR_NO_FILENAME
- * @a wim corresponds to a WIM created with wimlib_create_new_wim() rather
- * than a WIM read with wimlib_open_wim().
- * @retval ::WIMLIB_ERR_NOMEM
- * Failed to allocate needed memory.
- * @retval ::WIMLIB_ERR_OPEN
- * The WIM file associated with @a wim could not be re-opened read-write.
- * @retval ::WIMLIB_ERR_READ
- * ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY was specified in @a flags, but data
- * from the WIM file associated with @a wim could not be read to compute
- * the SHA1 message digests, or the old integrity table (if it existed)
- * could not be read.
- * @retval ::WIMLIB_ERR_RESOURCE_ORDER
- * Stream resources appeared in the WIM after the XML data or integrity
- * table, so we could not safely overwrite the XML data and integrity
- * table. Note: this error should never be received from WIMs that were
- * written by this library.
- * @retval ::WIMLIB_ERR_WRITE
- * Failed to write the WIM header, the XML data, or the integrity table to
- * the WIM file associated with @a wim.
+ * This function is deprecated; call wimlib_overwrite() without the
+ * WIMLIB_WRITE_FLAG_REBUILD flag instead.
*/
-extern int wimlib_overwrite_xml_and_header(WIMStruct *wim, int flags);
+extern int wimlib_overwrite_xml_and_header(WIMStruct *wim, int write_flags);
/**
* Prints information about one image, or all images, contained in a WIM.
* @param image
* The image inside the WIM to write. Use ::WIM_ALL_IMAGES to include all
* images.
- * @param flags
+ * @param write_flags
* Bitwise OR of ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY and/or
* ::WIMLIB_WRITE_FLAG_SHOW_PROGRESS. If
* ::WIMLIB_WRITE_FLAG_CHECK_INTEGRITY is given, an integrity table is
* included in the WIM being written. If ::WIMLIB_WRITE_FLAG_SHOW_PROGRESS
* is given, the progress of the calculation of the integrity table is
* shown.
+ * @param num_threads
+ * Number of threads to use for compressing data. Autodetected if set to
+ * 0. Note: if no data compression needs to be done, no threads will be
+ * created regardless of this parameter (e.g. if writing an uncompressed
+ * WIM, or exporting an image from a compressed WIM to another WIM of the
+ * same compression type).
*
* @return 0 on success; nonzero on error.
* @retval ::WIMLIB_ERR_DECOMPRESSION
* An error occurred when trying to write data to the new WIM file at @a
* path.
*/
-extern int wimlib_write(WIMStruct *wim, const char *path, int image, int flags);
+extern int wimlib_write(WIMStruct *wim, const char *path, int image,
+ int write_flags, unsigned num_threads);