1 #ifndef _WIMLIB_RESOURCE_H
2 #define _WIMLIB_RESOURCE_H
4 #include "wimlib/callback.h"
5 #include "wimlib/file_io.h"
6 #include "wimlib/list.h"
7 #include "wimlib/sha1.h"
8 #include "wimlib/types.h"
10 struct wim_lookup_table_entry;
11 struct wim_image_metadata;
13 /* Specification of a resource in a WIM file.
15 * If a `struct wim_lookup_table_entry' lte has
16 * (lte->resource_location == RESOURCE_IN_WIM), then lte->wim_res_spec points to
17 * an instance of this structure.
19 * Normally, there is a one-to-one correspondence between WIM lookup table
20 * entries ("streams", each of which may be the contents of a file, for example)
21 * and WIM resources. However, WIM resources with the
22 * WIM_RESHDR_FLAG_PACKED_STREAMS flag set may actually contain multiple streams
23 * compressed together. */
24 struct wim_resource_spec {
25 /* The WIM containing this resource. @wim->in_fd is expected to be a
26 * file descriptor to the underlying WIM file, opened for reading. */
29 /* The offset, in bytes, from the start of WIM file at which this
33 /* The size of this resource in the WIM file. For compressed resources
34 * this is the compressed size. */
37 /* The number of bytes of uncompressed data this resource decompresses
39 u64 uncompressed_size;
41 /* The list of streams this resource contains. */
42 struct list_head stream_list;
44 /* Flags for this resource (WIM_RESHDR_FLAG_*) */
47 /* This flag will be set if the WIM is pipable. In such cases, the
48 * resource will be in a slightly different format if it is compressed.
49 * This is a wimlib extension. */
56 /* On-disk version of a WIM resource header. */
57 struct wim_reshdr_disk {
58 /* Size of the resource as it appears in the WIM file (possibly
62 /* Zero or more of the WIM_RESHDR_FLAG_* flags. These indicate, for
63 * example, whether the resource is compressed or not. */
66 /* Offset of the resource from the start of the WIM file, in bytes. */
69 /* Uncompressed size of the resource, in bytes. */
70 le64 uncompressed_size;
73 /* In-memory version of a WIM resource header. */
78 u64 uncompressed_size;
81 /* Flags for the `flags' field of WIM resource headers. */
83 /* Unknown meaning; may be intended to indicate spaces in the WIM that are free
84 * to overwrite. Currently ignored by wimlib. */
85 #define WIM_RESHDR_FLAG_FREE 0x01
87 /* The resource is a metadata resource for a WIM image, or is the lookup table
88 * or XML data for the WIM. */
89 #define WIM_RESHDR_FLAG_METADATA 0x02
91 /* The resource is compressed using the WIM's default compression type and uses
92 * the regular chunk table format. */
93 #define WIM_RESHDR_FLAG_COMPRESSED 0x04
95 /* Unknown meaning; may be intended to indicate a partial stream. Currently
96 * ignored by wimlib. */
97 #define WIM_RESHDR_FLAG_SPANNED 0x08
99 /* The resource is packed in a special format that may contain multiple
100 * underlying streams, or this resource entry represents a stream packed into
101 * one such resource. When resources have this flag set, the WIM version number
102 * should be WIM_VERSION_PACKED_STREAMS. */
103 #define WIM_RESHDR_FLAG_PACKED_STREAMS 0x10
105 /* Magic number in the 'uncompressed_size' field of the resource header that
106 * identifies the main entry for a pack. */
107 #define WIM_PACK_MAGIC_NUMBER 0x100000000ULL
109 /* Returns true if the specified WIM resource is compressed, using either the
110 * original chunk table layout or the alternate layout for resources that may
111 * contain multiple packed streams. */
113 resource_is_compressed(const struct wim_resource_spec *rspec)
115 return (rspec->flags & (WIM_RESHDR_FLAG_COMPRESSED |
116 WIM_RESHDR_FLAG_PACKED_STREAMS));
120 copy_reshdr(struct wim_reshdr *dest, const struct wim_reshdr *src)
122 memcpy(dest, src, sizeof(struct wim_reshdr));
126 zero_reshdr(struct wim_reshdr *reshdr)
128 memset(reshdr, 0, sizeof(struct wim_reshdr));
132 wim_res_hdr_to_spec(const struct wim_reshdr *reshdr, WIMStruct *wim,
133 struct wim_resource_spec *rspec);
136 wim_res_spec_to_hdr(const struct wim_resource_spec *rspec,
137 struct wim_reshdr *reshdr);
140 get_wim_reshdr(const struct wim_reshdr_disk *disk_reshdr,
141 struct wim_reshdr *reshdr);
144 put_wim_reshdr(const struct wim_reshdr *reshdr,
145 struct wim_reshdr_disk *disk_reshdr);
147 /* Alternate chunk table format for resources with
148 * WIM_RESHDR_FLAG_PACKED_STREAMS set. */
149 struct alt_chunk_table_header_disk {
150 /* Uncompressed size of the resource in bytes. */
153 /* Number of bytes each compressed chunk decompresses into, except
154 * possibly the last which decompresses into the remainder. */
157 /* Compression format used for compressed chunks:
162 le32 compression_format;
164 /* This header is directly followed by a table of compressed sizes of
168 /* wimlib internal flags used when writing resources. */
169 #define WIMLIB_WRITE_RESOURCE_FLAG_RECOMPRESS 0x00000001
170 #define WIMLIB_WRITE_RESOURCE_FLAG_PIPABLE 0x00000002
171 #define WIMLIB_WRITE_RESOURCE_FLAG_PACK_STREAMS 0x00000004
173 /* Functions to read streams */
176 read_partial_wim_stream_into_buf(const struct wim_lookup_table_entry *lte,
177 size_t size, u64 offset, void *buf);
180 read_full_stream_into_buf(const struct wim_lookup_table_entry *lte, void *buf);
183 read_full_stream_into_alloc_buf(const struct wim_lookup_table_entry *lte,
187 wim_reshdr_to_data(const struct wim_reshdr *reshdr,
188 WIMStruct *wim, void **buf_ret);
191 skip_wim_stream(struct wim_lookup_table_entry *lte);
194 read_stream_prefix(const struct wim_lookup_table_entry *lte,
195 u64 size, consume_data_callback_t cb,
198 typedef int (*read_stream_list_begin_stream_t)(struct wim_lookup_table_entry *lte,
201 typedef int (*read_stream_list_end_stream_t)(struct wim_lookup_table_entry *lte,
205 #define VERIFY_STREAM_HASHES 0x1
206 #define COMPUTE_MISSING_STREAM_HASHES 0x2
207 #define STREAM_LIST_ALREADY_SORTED 0x4
208 #define BEGIN_STREAM_STATUS_SKIP_STREAM -1
210 /* Callback functions and contexts for read_stream_list(). */
211 struct read_stream_list_callbacks {
213 /* Called when a stream is about to be read. */
214 read_stream_list_begin_stream_t begin_stream;
216 /* Called when a chunk of data has been read. */
217 consume_data_callback_t consume_chunk;
219 /* Called when a stream has been fully read. */
220 read_stream_list_end_stream_t end_stream;
222 /* Parameter passed to @begin_stream. */
223 void *begin_stream_ctx;
225 /* Parameter passed to @consume_chunk. */
226 void *consume_chunk_ctx;
228 /* Parameter passed to @end_stream. */
229 void *end_stream_ctx;
233 read_stream_list(struct list_head *stream_list,
234 size_t list_head_offset,
235 const struct read_stream_list_callbacks *cbs,
238 /* Functions to extract streams. */
241 extract_stream(struct wim_lookup_table_entry *lte,
243 consume_data_callback_t extract_chunk,
244 void *extract_chunk_arg);
247 extract_stream_to_fd(struct wim_lookup_table_entry *lte,
248 struct filedes *fd, u64 size);
251 extract_chunk_to_fd(const void *chunk, size_t size, void *_fd_p);
253 /* Miscellaneous stream functions. */
256 sha1_stream(struct wim_lookup_table_entry *lte);
258 /* Functions to read/write metadata resources. */
261 read_metadata_resource(WIMStruct *wim,
262 struct wim_image_metadata *image_metadata);
265 write_metadata_resource(WIMStruct *wim, int image, int write_resource_flags);
267 /* Definitions specific to pipable WIM resources. */
269 /* Arbitrary number to begin each stream in the pipable WIM, used for sanity
271 #define PWM_STREAM_MAGIC 0x2b9b9ba2443db9d8ULL
273 /* Header that precedes each resource in a pipable WIM. */
274 struct pwm_stream_hdr {
276 le64 uncompressed_size; /* +8 */
277 u8 hash[SHA1_HASH_SIZE]; /* +16 */
278 le32 flags; /* +36 */
282 /* Extra flag for the @flags field in `struct pipable_wim_stream_hdr': Indicates
283 * that the SHA1 message digest of the stream has not been calculated.
284 * Currently only used for the XML data. */
285 #define PWM_RESHDR_FLAG_UNHASHED 0x100
287 /* Header that precedes each chunk of a compressed resource in a pipable WIM.
289 struct pwm_chunk_hdr {
290 le32 compressed_size;
293 #endif /* _WIMLIB_RESOURCE_H */