1 #ifndef _WIMLIB_LOOKUP_TABLE_H
2 #define _WIMLIB_LOOKUP_TABLE_H
3 #include "wimlib_internal.h"
8 /* Size of each lookup table entry in the WIM file. */
9 #define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
11 #define LOOKUP_FLAG_ADS_OK 0x00000001
12 #define LOOKUP_FLAG_DIRECTORY_OK 0x00000002
15 //#define LOOKUP_FLAG_FOLLOW_SYMLINKS 0x00000004
18 /* A lookup table that is used to translate the hash codes of dentries into the
19 * offsets and sizes of uncompressed or compressed file resources. It is
20 * implemented as a hash table. */
22 struct hlist_head *array;
30 struct ntfs_location {
32 char *stream_name_utf16;
33 u16 stream_name_utf16_num_chars;
34 struct _ntfs_volume **ntfs_vol_p;
35 bool is_reparse_point;
39 /* An enumerated type that identifies where the stream corresponding to this
40 * lookup table entry is actually located.
42 * If we open a WIM and read its lookup table, the location is set to
43 * RESOURCE_IN_WIM since all the streams will initially be located in the WIM.
44 * However, to deal with problems such as image capture and image mount, we
45 * allow the actual location of the stream to be somewhere else, such as an
48 enum resource_location {
49 /* The lookup table entry does not correspond to a stream (this state
50 * should exist only temporarily) */
51 RESOURCE_NONEXISTENT = 0,
53 /* The stream resource is located in a WIM file. The WIMStruct for the
54 * WIM file will be pointed to by the @wim member. */
57 /* The stream resource is located in an external file. The name of the
58 * file will be provided by @file_on_disk member. In addition, if
59 * @file_on_disk_fp is not NULL, it will be an open FILE * to the file.
61 RESOURCE_IN_FILE_ON_DISK,
63 /* The stream resource is located in an external file in the staging
64 * directory for a read-write mount. */
65 RESOURCE_IN_STAGING_FILE,
67 /* The stream resource is directly attached in an in-memory buffer
68 * pointed to by @attached_buffer. */
69 RESOURCE_IN_ATTACHED_BUFFER,
71 /* The stream resource is located in an NTFS volume. It is identified
72 * by volume, filename, data stream name, and by whether it is a reparse
73 * point or not. @ntfs_loc points to a structure containing this
75 RESOURCE_IN_NTFS_VOLUME,
79 * An entry in the lookup table in the WIM file.
81 * It is used to find data streams for files in the WIM.
83 * Metadata resources and reparse point data buffers will also have lookup table
84 * entries associated with the data.
86 * The lookup_table_entry for a given dentry or alternate stream entry in the
87 * WIM is found using the SHA1 message digest field.
89 struct lookup_table_entry {
91 /* List of lookup table entries in this hash bucket */
92 struct hlist_node hash_list;
94 /* Location and size of the stream in the WIM, whether it is compressed
95 * or not, and whether it's a metadata resource or not. This is an
97 struct resource_entry resource_entry;
99 /* Specifies which part of the split WIM the resource is located in.
100 * This is on on-disk field.
102 * In stand-alone WIMs, this must be 1.
104 * In split WIMs, every split WIM part has its own lookup table, and in
105 * read_lookup_table() it's currently expected that the part number of
106 * each lookup table entry in a split WIM part's lookup table is the
107 * same as the part number of that split WIM part. So this makes this
108 * field redundant since we store a pointer to the corresponding
109 * WIMStruct in the lookup table entry anyway.
113 /* See enum resource_location above */
114 u16 resource_location;
117 * Number of times this lookup table entry is referenced by dentries.
118 * Unfortunately, this field is not always set correctly in Microsoft's
119 * WIMs, so we have no choice but to fix it if more references to the
120 * lookup table entry are found than stated here. */
124 /* (On-disk field) SHA1 message digest of the stream referenced
125 * by this lookup table entry */
126 u8 hash[SHA1_HASH_SIZE];
128 /* First 4 or 8 bytes of the SHA1 message digest, used for
129 * inserting the entry into the hash table. Since the SHA1
130 * message digest can be considered random, we don't really need
131 * the full 20 byte hash just to insert the entry in a hash
140 /* Pointers to somewhere where the stream is actually located. See the
141 * comments for the @resource_location field above. */
145 char *staging_file_name;
148 struct ntfs_location *ntfs_loc;
152 /* @file_on_disk_fp and @attr are both used to cache file/stream
153 * handles so we don't have re-open them on every read */
155 /* Valid iff resource_location == RESOURCE_IN_FILE_ON_DISK */
156 FILE *file_on_disk_fp;
158 /* Valid iff resource_location == RESOURCE_IN_NTFS_VOLUME */
159 struct _ntfs_attr *attr;
162 /* Pointer to inode that contains the opened file descriptors to
163 * this stream (valid iff resource_location ==
164 * RESOURCE_IN_STAGING_FILE) */
165 struct inode *lte_inode;
168 /* When a WIM file is written, out_refcnt starts at 0 and is incremented
169 * whenever the file resource pointed to by this lookup table entry
170 * needs to be written. The file resource only need to be written when
171 * out_refcnt is nonzero, since otherwise it is not referenced by any
178 /* When a WIM file is written, @output_resource_entry is filled
179 * in with the resource entry for the output WIM. This will not
180 * necessarily be the same as the @resource_entry since: - The
181 * stream may have a different offset in the new WIM - The
182 * stream may have a different compressed size in the new WIM if
183 * the compression type changed
185 struct resource_entry output_resource_entry;
187 struct list_head msg_list;
191 /* This field is used for the special hardlink or symlink image
192 * extraction mode. In these mode, all identical files are linked
193 * together, and @extracted_file will be set to the filename of the
194 * first extracted file containing this stream. */
195 char *extracted_file;
197 /* List of lookup table entries that correspond to streams that have
198 * been extracted to the staging directory when modifying a read-write
200 struct list_head staging_list;
204 static inline u64 wim_resource_size(const struct lookup_table_entry *lte)
206 return lte->resource_entry.original_size;
209 static inline u64 wim_resource_chunks(const struct lookup_table_entry *lte)
211 return (wim_resource_size(lte) + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE;
215 wim_resource_compressed_size(const struct lookup_table_entry *lte)
217 return lte->resource_entry.size;
221 * XXX Probably should store the compression type directly in the lookup table
225 wim_resource_compression_type(const struct lookup_table_entry *lte)
227 if (!(lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
228 || lte->resource_location != RESOURCE_IN_WIM)
229 return WIM_COMPRESSION_TYPE_NONE;
230 return wimlib_get_compression_type(lte->wim);
234 extern struct lookup_table *new_lookup_table(size_t capacity);
236 extern void lookup_table_insert(struct lookup_table *table,
237 struct lookup_table_entry *lte);
239 /* Unlinks a lookup table entry from the table; does not free it. */
240 static inline void lookup_table_unlink(struct lookup_table *table,
241 struct lookup_table_entry *lte)
243 hlist_del(<e->hash_list);
244 table->num_entries--;
247 extern struct lookup_table_entry *new_lookup_table_entry();
249 extern struct lookup_table_entry *
250 clone_lookup_table_entry(const struct lookup_table_entry *lte);
252 extern int for_lookup_table_entry(struct lookup_table *table,
253 int (*visitor)(struct lookup_table_entry *, void *),
256 extern struct lookup_table_entry *
257 __lookup_resource(const struct lookup_table *table, const u8 hash[]);
259 extern int lookup_resource(WIMStruct *w, const char *path,
260 int lookup_flags, struct dentry **dentry_ret,
261 struct lookup_table_entry **lte_ret,
262 u16 *stream_idx_ret);
264 extern void lte_decrement_refcnt(struct lookup_table_entry *lte,
265 struct lookup_table *table);
267 extern void lte_decrement_num_opened_fds(struct lookup_table_entry *lte);
270 extern int lte_zero_out_refcnt(struct lookup_table_entry *entry, void *ignore);
271 extern int lte_zero_real_refcnt(struct lookup_table_entry *entry, void *ignore);
272 extern int lte_zero_extracted_file(struct lookup_table_entry *lte, void *ignore);
273 extern int lte_free_extracted_file(struct lookup_table_entry *lte, void *ignore);
275 extern void print_lookup_table_entry(const struct lookup_table_entry *entry);
277 extern int read_lookup_table(WIMStruct *w);
279 extern void free_lookup_table(struct lookup_table *table);
281 extern int write_lookup_table_entry(struct lookup_table_entry *lte, void *__out);
283 extern void free_lookup_table_entry(struct lookup_table_entry *lte);
285 extern int dentry_resolve_ltes(struct dentry *dentry, void *__table);
286 extern int dentry_unresolve_ltes(struct dentry *dentry, void *ignore);
288 int write_lookup_table(struct lookup_table *table, FILE *out,
289 struct resource_entry *out_res_entry);
291 /* Unlinks and frees an entry from a lookup table. */
292 static inline void lookup_table_remove(struct lookup_table *table,
293 struct lookup_table_entry *lte)
295 lookup_table_unlink(table, lte);
296 free_lookup_table_entry(lte);
299 static inline struct resource_entry* wim_metadata_resource_entry(WIMStruct *w)
301 return &w->image_metadata[
302 w->current_image - 1].metadata_lte->resource_entry;
305 static inline struct lookup_table_entry *
306 inode_stream_lte_resolved(const struct inode *inode, unsigned stream_idx)
308 wimlib_assert(inode->resolved);
309 wimlib_assert(stream_idx <= inode->num_ads);
313 return inode->ads_entries[stream_idx - 1].lte;
316 static inline struct lookup_table_entry *
317 inode_stream_lte_unresolved(const struct inode *inode, unsigned stream_idx,
318 const struct lookup_table *table)
320 wimlib_assert(!inode->resolved);
321 wimlib_assert(stream_idx <= inode->num_ads);
325 return __lookup_resource(table, inode->hash);
327 return __lookup_resource(table,
329 stream_idx - 1].hash);
332 * Returns the lookup table entry for stream @stream_idx of the inode, where
333 * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
334 * corresponds to an alternate data stream.
336 * This works for both resolved and un-resolved dentries.
338 static inline struct lookup_table_entry *
339 inode_stream_lte(const struct inode *inode, unsigned stream_idx,
340 const struct lookup_table *table)
343 return inode_stream_lte_resolved(inode, stream_idx);
345 return inode_stream_lte_unresolved(inode, stream_idx, table);
349 static inline const u8 *inode_stream_hash_unresolved(const struct inode *inode,
352 wimlib_assert(!inode->resolved);
353 wimlib_assert(stream_idx <= inode->num_ads);
357 return inode->ads_entries[stream_idx - 1].hash;
361 static inline const u8 *inode_stream_hash_resolved(const struct inode *inode,
364 struct lookup_table_entry *lte;
365 lte = inode_stream_lte_resolved(inode, stream_idx);
373 * Returns the hash for stream @stream_idx of the inode, where stream_idx = 0
374 * means the default un-named file stream, and stream_idx >= 1 corresponds to an
375 * alternate data stream.
377 * This works for both resolved and un-resolved dentries.
379 static inline const u8 *inode_stream_hash(const struct inode *inode,
383 return inode_stream_hash_resolved(inode, stream_idx);
385 return inode_stream_hash_unresolved(inode, stream_idx);
388 static inline u16 inode_stream_name_len(const struct inode *inode,
391 wimlib_assert(stream_idx <= inode->num_ads);
395 return inode->ads_entries[stream_idx - 1].stream_name_len;
398 static inline struct lookup_table_entry *
399 inode_unnamed_lte_resolved(const struct inode *inode)
401 wimlib_assert(inode->resolved);
402 for (unsigned i = 0; i <= inode->num_ads; i++)
403 if (inode_stream_name_len(inode, i) == 0 &&
404 !is_zero_hash(inode_stream_hash_resolved(inode, i)))
405 return inode_stream_lte_resolved(inode, i);
409 static inline struct lookup_table_entry *
410 inode_unnamed_lte_unresolved(const struct inode *inode,
411 const struct lookup_table *table)
413 wimlib_assert(!inode->resolved);
414 for (unsigned i = 0; i <= inode->num_ads; i++)
415 if (inode_stream_name_len(inode, i) == 0 &&
416 !is_zero_hash(inode_stream_hash_unresolved(inode, i)))
417 return inode_stream_lte_unresolved(inode, i, table);
421 extern struct lookup_table_entry *
422 inode_unnamed_lte(const struct inode *inode,
423 const struct lookup_table *table);