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
13 #define LOOKUP_FLAG_FOLLOW_SYMLINKS 0x00000004
16 /* A lookup table that is used to translate the hash codes of dentries into the
17 * offsets and sizes of uncompressed or compressed file resources. It is
18 * implemented as a hash table. */
20 struct hlist_head *array;
28 * An entry in the lookup table in the WIM file.
30 * It is used to find data streams for files in the WIM.
32 * The lookup_table_entry for a given dentry in the WIM is found using the SHA1
33 * message digest field.
35 struct lookup_table_entry {
37 /* List of lookup table entries in this hash bucket */
38 struct hlist_node hash_list;
40 /* @resource_entry is read from the lookup table in the WIM
41 * file; it says where to find the file resource in the WIM
42 * file, and whether it is compressed or not. */
43 struct resource_entry resource_entry;
45 /* Currently ignored; set to 1 in new lookup table entries. */
48 /* If %true, this lookup table entry corresponds to a symbolic link
49 * reparse buffer. @symlink_reparse_data_buf will give the target of
50 * the symbolic link. */
52 RESOURCE_NONEXISTENT = 0,
54 RESOURCE_IN_FILE_ON_DISK,
55 RESOURCE_IN_STAGING_FILE,
56 RESOURCE_IN_ATTACHED_BUFFER,
59 /* Number of times this lookup table entry is referenced by dentries. */
63 /* SHA1 hash of the file resource pointed to by this lookup
65 u8 hash[SHA1_HASH_SIZE];
67 /* First 4 or 8 bytes of the SHA1 hash, used for inserting the
68 * entry into the hash table. Since the SHA1 hashes can be
69 * considered random, we don't really need the full 20 byte hash
70 * just to insert the entry in a hash table. */
74 /* If @file_on_disk != NULL, the file resource indicated by this lookup
75 * table entry is not in the WIM file, but rather a file on disk; this
76 * occurs for files that are added to the WIM. In that case,
77 * file_on_disk is the name of the file in the outside filesystem.
78 * It will not be compressed, and its size will be given by
79 * resource_entry.size and resource_entry.original_size. */
83 char *staging_file_name;
87 struct lookup_table_entry *next_lte_in_swm;
88 FILE *file_on_disk_fp;
91 /* File descriptors table for this data stream */
93 u16 num_allocated_fds;
94 struct wimlib_fd **fds;
97 /* When a WIM file is written, out_refcnt starts at 0 and is incremented
98 * whenever the file resource pointed to by this lookup table entry
99 * needs to be written. Naturally, the file resource only need to be
100 * written when out_refcnt is 0. Incrementing it further is needed to
101 * find the correct reference count to write to the lookup table in the
102 * output file, which may be less than the regular refcnt if not all
103 * images in the WIM file are written.
105 * output_resource_entry is the struct resource_entry for the position of the
106 * file resource when written to the output file. */
109 struct resource_entry output_resource_entry;
110 char *extracted_file;
113 /* Circular linked list of streams that share the same lookup table
116 * This list of streams may include streams from different hard link
117 * sets that happen to be the same. */
118 struct list_head lte_group_list;
120 /* List of lookup table entries that correspond to streams that have
121 * been extracted to the staging directory when modifying a read-write
123 struct list_head staging_list;
126 static inline u64 wim_resource_size(const struct lookup_table_entry *lte)
128 return lte->resource_entry.original_size;
132 wim_resource_compressed_size(const struct lookup_table_entry *lte)
134 return lte->resource_entry.size;
138 * XXX Probably should store the compression type directly in the lookup table
142 wim_resource_compression_type(const struct lookup_table_entry *lte)
144 if (!(lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
145 || lte->resource_location != RESOURCE_IN_WIM)
146 return WIM_COMPRESSION_TYPE_NONE;
147 return wimlib_get_compression_type(lte->wim);
151 extern struct lookup_table *new_lookup_table(size_t capacity);
153 extern void lookup_table_insert(struct lookup_table *table,
154 struct lookup_table_entry *lte);
156 /* Unlinks a lookup table entry from the table; does not free it. */
157 static inline void lookup_table_unlink(struct lookup_table *table,
158 struct lookup_table_entry *lte)
160 hlist_del(<e->hash_list);
161 table->num_entries--;
165 extern struct lookup_table_entry *
166 lookup_table_decrement_refcnt(struct lookup_table* table, const u8 hash[]);
168 extern struct lookup_table_entry *
169 lte_decrement_refcnt(struct lookup_table_entry *lte,
170 struct lookup_table *table);
173 extern struct lookup_table_entry *new_lookup_table_entry();
175 extern int for_lookup_table_entry(struct lookup_table *table,
176 int (*visitor)(struct lookup_table_entry *, void *),
179 extern struct lookup_table_entry *
180 __lookup_resource(const struct lookup_table *table, const u8 hash[]);
182 extern int lookup_resource(WIMStruct *w, const char *path,
183 int lookup_flags, struct dentry **dentry_ret,
184 struct lookup_table_entry **lte_ret,
185 unsigned *stream_idx_ret);
187 extern int zero_out_refcnts(struct lookup_table_entry *entry, void *ignore);
189 extern void print_lookup_table_entry(const struct lookup_table_entry *entry);
191 extern int read_lookup_table(WIMStruct *w);
193 extern void free_lookup_table(struct lookup_table *table);
195 extern int write_lookup_table_entry(struct lookup_table_entry *lte, void *__out);
197 extern void free_lookup_table_entry(struct lookup_table_entry *lte);
199 extern int dentry_resolve_ltes(struct dentry *dentry, void *__table);
201 /* Writes the lookup table to the output file. */
202 static inline int write_lookup_table(struct lookup_table *table, FILE *out)
204 return for_lookup_table_entry(table, write_lookup_table_entry, out);
207 /* Unlinks and frees an entry from a lookup table. */
208 static inline void lookup_table_remove(struct lookup_table *table,
209 struct lookup_table_entry *lte)
211 lookup_table_unlink(table, lte);
212 free_lookup_table_entry(lte);
215 static inline struct resource_entry* wim_metadata_resource_entry(WIMStruct *w)
217 return &w->image_metadata[
218 w->current_image - 1].metadata_lte->resource_entry;
221 static inline struct lookup_table_entry *
222 dentry_stream_lte_resolved(const struct dentry *dentry, unsigned stream_idx)
224 wimlib_assert(dentry->resolved);
225 wimlib_assert(stream_idx <= dentry->num_ads);
229 return dentry->ads_entries[stream_idx - 1].lte;
232 static inline struct lookup_table_entry *
233 dentry_stream_lte_unresolved(const struct dentry *dentry, unsigned stream_idx,
234 const struct lookup_table *table)
236 wimlib_assert(!dentry->resolved);
237 wimlib_assert(stream_idx <= dentry->num_ads);
241 return __lookup_resource(table, dentry->hash);
243 return __lookup_resource(table,
245 stream_idx - 1].hash);
248 * Returns the lookup table entry for stream @stream_idx of the dentry, where
249 * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
250 * corresponds to an alternate data stream.
252 * This works for both resolved and un-resolved dentries.
254 static inline struct lookup_table_entry *
255 dentry_stream_lte(const struct dentry *dentry, unsigned stream_idx,
256 const struct lookup_table *table)
258 if (dentry->resolved)
259 return dentry_stream_lte_resolved(dentry, stream_idx);
261 return dentry_stream_lte_unresolved(dentry, stream_idx, table);
265 static inline const u8 *dentry_stream_hash_unresolved(const struct dentry *dentry,
268 wimlib_assert(!dentry->resolved);
269 wimlib_assert(stream_idx <= dentry->num_ads);
273 return dentry->ads_entries[stream_idx - 1].hash;
276 static inline const u8 *dentry_stream_hash_resolved(const struct dentry *dentry,
279 struct lookup_table_entry *lte;
280 lte = dentry_stream_lte_resolved(dentry, stream_idx);
288 * Returns the hash for stream @stream_idx of the dentry, where stream_idx = 0
289 * means the default un-named file stream, and stream_idx >= 1 corresponds to an
290 * alternate data stream.
292 * This works for both resolved and un-resolved dentries.
294 static inline const u8 *dentry_stream_hash(const struct dentry *dentry,
297 if (dentry->resolved)
298 return dentry_stream_hash_resolved(dentry, stream_idx);
300 return dentry_stream_hash_unresolved(dentry, stream_idx);
303 static inline struct lookup_table_entry *
304 dentry_first_lte_resolved(const struct dentry *dentry)
306 struct lookup_table_entry *lte;
307 wimlib_assert(dentry->resolved);
309 for (unsigned i = 0; i <= dentry->num_ads; i++) {
310 lte = dentry_stream_lte_resolved(dentry, i);
317 static inline struct lookup_table_entry *
318 dentry_first_lte_unresolved(const struct dentry *dentry,
319 const struct lookup_table *table)
321 struct lookup_table_entry *lte;
322 wimlib_assert(!dentry->resolved);
324 for (unsigned i = 0; i <= dentry->num_ads; i++) {
325 lte = dentry_stream_lte_unresolved(dentry, i, table);
332 extern struct lookup_table_entry *
333 dentry_first_lte(const struct dentry *dentry, const struct lookup_table *table);