1 #ifndef _WIMLIB_APPLY_H
2 #define _WIMLIB_APPLY_H
3
4 #include "wimlib/compiler.h"
5 #include "wimlib/file_io.h"
6 #include "wimlib/list.h"
7 #include "wimlib/progress.h"
8 #include "wimlib/types.h"
9 #include "wimlib.h"
10
11 /* These can be treated as counts (for required_features) or booleans (for
12 * supported_features). */
13 struct wim_features {
14 unsigned long readonly_files;
15 unsigned long hidden_files;
16 unsigned long system_files;
17 unsigned long archive_files;
18 unsigned long compressed_files;
19 unsigned long encrypted_files;
20 unsigned long encrypted_directories;
21 unsigned long not_context_indexed_files;
22 unsigned long sparse_files;
23 unsigned long named_data_streams;
24 unsigned long hard_links;
25 unsigned long reparse_points;
26 unsigned long symlink_reparse_points;
27 unsigned long other_reparse_points;
28 unsigned long security_descriptors;
29 unsigned long short_names;
30 unsigned long unix_data;
31 unsigned long object_ids;
32 unsigned long timestamps;
33 unsigned long case_sensitive_filenames;
34 unsigned long xattrs;
35 };
36
37 struct blob_descriptor;
38 struct read_blob_callbacks;
39 struct apply_operations;
40 struct wim_dentry;
41
42 struct apply_ctx {
43 /* The WIMStruct from which files are being extracted from the currently
44 * selected image. */
45 WIMStruct *wim;
46
47 /* The target of the extraction, usually the path to a directory. */
48 const tchar *target;
49
50 /* Length of @target in tchars. */
51 size_t target_nchars;
52
53 /* Extraction flags (WIMLIB_EXTRACT_FLAG_*) */
54 int extract_flags;
55
56 /* User-provided progress function, or NULL if not specified. */
57 wimlib_progress_func_t progfunc;
58 void *progctx;
59
60 /* Progress data buffer, with progress.extract initialized. */
61 union wimlib_progress_info progress;
62
63 /* Features required to extract the files (with counts) */
64 struct wim_features required_features;
65
66 /* Features supported by the extraction mode (with booleans) */
67 struct wim_features supported_features;
68
69 /* The members below should not be used outside of extract.c */
70 const struct apply_operations *apply_ops;
71 u64 next_progress;
72 unsigned long invalid_sequence;
73 unsigned long num_blobs_remaining;
74 struct list_head blob_list;
75 const struct read_blob_callbacks *saved_cbs;
76 struct filedes tmpfile_fd;
77 tchar *tmpfile_name;
78 unsigned int count_until_file_progress;
79 };
80
81 /* Maximum number of UNIX file descriptors, NTFS attributes, or Windows file
82 * handles that can be opened simultaneously to extract a blob to multiple
83 * destinations. */
84 #define MAX_OPEN_FILES 512
85
86 static inline int
extract_progress(struct apply_ctx * ctx,enum wimlib_progress_msg msg)87 extract_progress(struct apply_ctx *ctx, enum wimlib_progress_msg msg)
88 {
89 return call_progress(ctx->progfunc, msg, &ctx->progress, ctx->progctx);
90 }
91
92 extern int
93 do_file_extract_progress(struct apply_ctx *ctx, enum wimlib_progress_msg msg);
94
95 #define COUNT_PER_FILE_PROGRESS 256
96
97 static inline int
maybe_do_file_progress(struct apply_ctx * ctx,enum wimlib_progress_msg msg)98 maybe_do_file_progress(struct apply_ctx *ctx, enum wimlib_progress_msg msg)
99 {
100 ctx->progress.extract.current_file_count++;
101 if (unlikely(!--ctx->count_until_file_progress))
102 return do_file_extract_progress(ctx, msg);
103 return 0;
104 }
105
106 extern int
107 start_file_structure_phase(struct apply_ctx *ctx, u64 end_file_count);
108
109 extern int
110 start_file_metadata_phase(struct apply_ctx *ctx, u64 end_file_count);
111
112 /* Report that a file was created, prior to blob extraction. */
113 static inline int
report_file_created(struct apply_ctx * ctx)114 report_file_created(struct apply_ctx *ctx)
115 {
116 return maybe_do_file_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_FILE_STRUCTURE);
117 }
118
119 /* Report that file metadata was applied, after blob extraction. */
120 static inline int
report_file_metadata_applied(struct apply_ctx * ctx)121 report_file_metadata_applied(struct apply_ctx *ctx)
122 {
123 return maybe_do_file_progress(ctx, WIMLIB_PROGRESS_MSG_EXTRACT_METADATA);
124 }
125
126 extern int
127 end_file_structure_phase(struct apply_ctx *ctx);
128
129 extern int
130 end_file_metadata_phase(struct apply_ctx *ctx);
131
132 static inline int
report_apply_error(struct apply_ctx * ctx,int error_code,const tchar * path)133 report_apply_error(struct apply_ctx *ctx, int error_code, const tchar *path)
134 {
135 return report_error(ctx->progfunc, ctx->progctx, error_code, path);
136 }
137
138 extern bool
139 detect_sparse_region(const void *data, size_t size, size_t *len_ret);
140
141 static inline bool
maybe_detect_sparse_region(const void * data,size_t size,size_t * len_ret,bool enabled)142 maybe_detect_sparse_region(const void *data, size_t size, size_t *len_ret,
143 bool enabled)
144 {
145 if (!enabled) {
146 /* Force non-sparse without checking */
147 *len_ret = size;
148 return false;
149 }
150 return detect_sparse_region(data, size, len_ret);
151 }
152
153 #define inode_first_extraction_dentry(inode) \
154 ((inode)->i_first_extraction_alias)
155
156 #define inode_for_each_extraction_alias(dentry, inode) \
157 for (dentry = inode_first_extraction_dentry(inode); \
158 dentry != NULL; \
159 dentry = dentry->d_next_extraction_alias)
160
161 extern int
162 extract_blob_list(struct apply_ctx *ctx, const struct read_blob_callbacks *cbs);
163
164 /*
165 * Represents an extraction backend.
166 */
167 struct apply_operations {
168
169 /* Name of the extraction backend. */
170 const char *name;
171
172 /*
173 * Query the features supported by the extraction backend.
174 *
175 * @target
176 * The target string that was provided by the user. (Often a
177 * directory, but extraction backends are free to interpret this
178 * differently.)
179 *
180 * @supported_features
181 * A structure, each of whose members represents a feature that may
182 * be supported by the extraction backend. For each feature that
183 * the extraction backend supports, this routine must set the
184 * corresponding member to a nonzero value.
185 *
186 * Return 0 if successful; otherwise a positive wimlib error code.
187 */
188 int (*get_supported_features)(const tchar *target,
189 struct wim_features *supported_features);
190
191 /*
192 * Main extraction routine.
193 *
194 * The extraction backend is provided a list of dentries that have been
195 * prepared for extraction. It is free to extract them in any way that
196 * it chooses. Ideally, it should choose a method that maximizes
197 * performance.
198 *
199 * The target string will be provided in ctx->common.target. This might
200 * be a directory, although extraction backends are free to interpret it
201 * as they wish. TODO: in some cases, the common extraction code also
202 * interprets the target string. This should be completely isolated to
203 * extraction backends.
204 *
205 * The extraction flags will be provided in ctx->common.extract_flags.
206 * Extraction backends should examine them and implement the behaviors
207 * for as many flags as possible. Some flags are already handled by the
208 * common extraction code. TODO: this needs to be better formalized.
209 *
210 * @dentry_list, the list of dentries, will be ordered such that the
211 * ancestor of any dentry always precedes any descendents. Unless
212 * @single_tree_only is set, it's possible that the dentries consist of
213 * multiple disconnected trees.
214 *
215 * 'd_extraction_name' and 'd_extraction_name_nchars' of each dentry
216 * will be set to indicate the actual name with which the dentry should
217 * be extracted. This may or may not be the same as 'd_name'. TODO:
218 * really, the extraction backends should be responsible for generating
219 * 'd_extraction_name'.
220 *
221 * Each dentry will refer to a valid inode in 'd_inode'. Each inode
222 * will contain a list of dentries of that inode being extracted; this
223 * list may be shorter than the inode's full dentry list.
224 *
225 * The blobs required to be extracted will already be prepared in
226 * 'apply_ctx'. The extraction backend should call extract_blob_list()
227 * to extract them.
228 *
229 * The will_extract_dentry() utility function, given an arbitrary dentry
230 * in the WIM image (which may not be in the extraction list), can be
231 * used to determine if that dentry is in the extraction list.
232 *
233 * Return 0 if successful; otherwise a positive wimlib error code.
234 */
235 int (*extract)(struct list_head *dentry_list, struct apply_ctx *ctx);
236
237 /*
238 * Query whether the unnamed data stream of the specified file will be
239 * extracted as "externally backed" from the WIM archive itself. If so,
240 * then the extraction backend is assumed to handle this separately, and
241 * the common extraction code will not register a usage of the unnamed
242 * data stream's blob.
243 *
244 * This routine is optional.
245 *
246 * Return:
247 * < 0 if the file will *not* be externally backed.
248 * = 0 if the file will be externally backed.
249 * > 0 (wimlib error code) if another error occurred.
250 */
251 int (*will_back_from_wim)(struct wim_dentry *dentry, struct apply_ctx *ctx);
252
253 /*
254 * Size of the backend-specific extraction context. It must contain
255 * 'struct apply_ctx' as its first member.
256 */
257 size_t context_size;
258
259 /*
260 * Set this if the extraction backend only supports extracting dentries
261 * that form a single tree, not multiple trees.
262 */
263 bool single_tree_only;
264 };
265
266 #ifdef __WIN32__
267 extern const struct apply_operations win32_apply_ops;
268 #else
269 extern const struct apply_operations unix_apply_ops;
270 #endif
271
272 #ifdef WITH_NTFS_3G
273 extern const struct apply_operations ntfs_3g_apply_ops;
274 #endif
275
276 #endif /* _WIMLIB_APPLY_H */
277