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 * An entry in the lookup table in the WIM file.
32 * It is used to find data streams for files in the WIM.
34 * The lookup_table_entry for a given dentry in the WIM is found using the SHA1
35 * message digest field.
37 struct lookup_table_entry {
39 /* List of lookup table entries in this hash bucket */
40 struct hlist_node hash_list;
42 /* @resource_entry is read from the lookup table in the WIM
43 * file; it says where to find the file resource in the WIM
44 * file, and whether it is compressed or not. */
45 struct resource_entry resource_entry;
47 /* Currently ignored; set to 1 in new lookup table entries. */
50 /* If %true, this lookup table entry corresponds to a symbolic link
51 * reparse buffer. @symlink_reparse_data_buf will give the target of
52 * the symbolic link. */
54 RESOURCE_NONEXISTENT = 0,
56 RESOURCE_IN_FILE_ON_DISK,
57 RESOURCE_IN_STAGING_FILE,
58 RESOURCE_IN_ATTACHED_BUFFER,
61 /* Number of times this lookup table entry is referenced by dentries. */
65 /* SHA1 hash of the file resource pointed to by this lookup
67 u8 hash[SHA1_HASH_SIZE];
69 /* First 4 or 8 bytes of the SHA1 hash, used for inserting the
70 * entry into the hash table. Since the SHA1 hashes can be
71 * considered random, we don't really need the full 20 byte hash
72 * just to insert the entry in a hash table. */
76 /* If @file_on_disk != NULL, the file resource indicated by this lookup
77 * table entry is not in the WIM file, but rather a file on disk; this
78 * occurs for files that are added to the WIM. In that case,
79 * file_on_disk is the name of the file in the outside filesystem.
80 * It will not be compressed, and its size will be given by
81 * resource_entry.size and resource_entry.original_size. */
85 char *staging_file_name;
89 struct lookup_table_entry *next_lte_in_swm;
90 FILE *file_on_disk_fp;
93 /* File descriptors table for this data stream */
95 u16 num_allocated_fds;
96 struct wimlib_fd **fds;
99 /* When a WIM file is written, out_refcnt starts at 0 and is incremented
100 * whenever the file resource pointed to by this lookup table entry
101 * needs to be written. Naturally, the file resource only need to be
102 * written when out_refcnt is 0. Incrementing it further is needed to
103 * find the correct reference count to write to the lookup table in the
104 * output file, which may be less than the regular refcnt if not all
105 * images in the WIM file are written.
107 * output_resource_entry is the struct resource_entry for the position of the
108 * file resource when written to the output file. */
111 struct resource_entry output_resource_entry;
112 char *extracted_file;
115 /* Circular linked list of streams that share the same lookup table
118 * This list of streams may include streams from different hard link
119 * sets that happen to be the same. */
120 struct list_head lte_group_list;
122 /* List of lookup table entries that correspond to streams that have
123 * been extracted to the staging directory when modifying a read-write
125 struct list_head staging_list;
128 static inline u64 wim_resource_size(const struct lookup_table_entry *lte)
130 return lte->resource_entry.original_size;
134 wim_resource_compressed_size(const struct lookup_table_entry *lte)
136 return lte->resource_entry.size;
140 * XXX Probably should store the compression type directly in the lookup table
144 wim_resource_compression_type(const struct lookup_table_entry *lte)
146 if (!(lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
147 || lte->resource_location != RESOURCE_IN_WIM)
148 return WIM_COMPRESSION_TYPE_NONE;
149 return wimlib_get_compression_type(lte->wim);
153 extern struct lookup_table *new_lookup_table(size_t capacity);
155 extern void lookup_table_insert(struct lookup_table *table,
156 struct lookup_table_entry *lte);
158 /* Unlinks a lookup table entry from the table; does not free it. */
159 static inline void lookup_table_unlink(struct lookup_table *table,
160 struct lookup_table_entry *lte)
162 hlist_del(<e->hash_list);
163 table->num_entries--;
167 extern struct lookup_table_entry *
168 lookup_table_decrement_refcnt(struct lookup_table* table, const u8 hash[]);
170 extern struct lookup_table_entry *
171 lte_decrement_refcnt(struct lookup_table_entry *lte,
172 struct lookup_table *table);
175 extern struct lookup_table_entry *new_lookup_table_entry();
177 extern int for_lookup_table_entry(struct lookup_table *table,
178 int (*visitor)(struct lookup_table_entry *, void *),
181 extern struct lookup_table_entry *
182 __lookup_resource(const struct lookup_table *table, const u8 hash[]);
184 extern int lookup_resource(WIMStruct *w, const char *path,
185 int lookup_flags, struct dentry **dentry_ret,
186 struct lookup_table_entry **lte_ret,
187 unsigned *stream_idx_ret);
189 extern int zero_out_refcnts(struct lookup_table_entry *entry, void *ignore);
191 extern void print_lookup_table_entry(const struct lookup_table_entry *entry);
193 extern int read_lookup_table(WIMStruct *w);
195 extern void free_lookup_table(struct lookup_table *table);
197 extern int write_lookup_table_entry(struct lookup_table_entry *lte, void *__out);
199 extern void free_lookup_table_entry(struct lookup_table_entry *lte);
201 extern int dentry_resolve_ltes(struct dentry *dentry, void *__table);
203 /* Writes the lookup table to the output file. */
204 static inline int write_lookup_table(struct lookup_table *table, FILE *out)
206 return for_lookup_table_entry(table, write_lookup_table_entry, out);
209 /* Unlinks and frees an entry from a lookup table. */
210 static inline void lookup_table_remove(struct lookup_table *table,
211 struct lookup_table_entry *lte)
213 lookup_table_unlink(table, lte);
214 free_lookup_table_entry(lte);
217 static inline struct resource_entry* wim_metadata_resource_entry(WIMStruct *w)
219 return &w->image_metadata[
220 w->current_image - 1].metadata_lte->resource_entry;
223 static inline struct lookup_table_entry *
224 dentry_stream_lte_resolved(const struct dentry *dentry, unsigned stream_idx)
226 wimlib_assert(dentry->resolved);
227 wimlib_assert(stream_idx <= dentry->num_ads);
231 return dentry->ads_entries[stream_idx - 1].lte;
234 static inline struct lookup_table_entry *
235 dentry_stream_lte_unresolved(const struct dentry *dentry, unsigned stream_idx,
236 const struct lookup_table *table)
238 wimlib_assert(!dentry->resolved);
239 wimlib_assert(stream_idx <= dentry->num_ads);
243 return __lookup_resource(table, dentry->hash);
245 return __lookup_resource(table,
247 stream_idx - 1].hash);
250 * Returns the lookup table entry for stream @stream_idx of the dentry, where
251 * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
252 * corresponds to an alternate data stream.
254 * This works for both resolved and un-resolved dentries.
256 static inline struct lookup_table_entry *
257 dentry_stream_lte(const struct dentry *dentry, unsigned stream_idx,
258 const struct lookup_table *table)
260 if (dentry->resolved)
261 return dentry_stream_lte_resolved(dentry, stream_idx);
263 return dentry_stream_lte_unresolved(dentry, stream_idx, table);
267 static inline const u8 *dentry_stream_hash_unresolved(const struct dentry *dentry,
270 wimlib_assert(!dentry->resolved);
271 wimlib_assert(stream_idx <= dentry->num_ads);
275 return dentry->ads_entries[stream_idx - 1].hash;
278 static inline const u8 *dentry_stream_hash_resolved(const struct dentry *dentry,
281 struct lookup_table_entry *lte;
282 lte = dentry_stream_lte_resolved(dentry, stream_idx);
290 * Returns the hash for stream @stream_idx of the dentry, where stream_idx = 0
291 * means the default un-named file stream, and stream_idx >= 1 corresponds to an
292 * alternate data stream.
294 * This works for both resolved and un-resolved dentries.
296 static inline const u8 *dentry_stream_hash(const struct dentry *dentry,
299 if (dentry->resolved)
300 return dentry_stream_hash_resolved(dentry, stream_idx);
302 return dentry_stream_hash_unresolved(dentry, stream_idx);
305 static inline struct lookup_table_entry *
306 dentry_first_lte_resolved(const struct dentry *dentry)
308 struct lookup_table_entry *lte;
309 wimlib_assert(dentry->resolved);
311 for (unsigned i = 0; i <= dentry->num_ads; i++) {
312 lte = dentry_stream_lte_resolved(dentry, i);
319 static inline struct lookup_table_entry *
320 dentry_first_lte_unresolved(const struct dentry *dentry,
321 const struct lookup_table *table)
323 struct lookup_table_entry *lte;
324 wimlib_assert(!dentry->resolved);
326 for (unsigned i = 0; i <= dentry->num_ads; i++) {
327 lte = dentry_stream_lte_unresolved(dentry, i, table);
334 extern struct lookup_table_entry *
335 dentry_first_lte(const struct dentry *dentry, const struct lookup_table *table);