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[git/git.git] / list-objects-filter.c
1 #include "cache.h"
2 #include "dir.h"
3 #include "tag.h"
4 #include "commit.h"
5 #include "tree.h"
6 #include "blob.h"
7 #include "diff.h"
8 #include "tree-walk.h"
9 #include "revision.h"
10 #include "list-objects.h"
11 #include "list-objects-filter.h"
12 #include "list-objects-filter-options.h"
13 #include "oidmap.h"
14 #include "oidset.h"
15 #include "object-store.h"
16
17 /* Remember to update object flag allocation in object.h */
18 /*
19 * FILTER_SHOWN_BUT_REVISIT -- we set this bit on tree objects
20 * that have been shown, but should be revisited if they appear
21 * in the traversal (until we mark it SEEN). This is a way to
22 * let us silently de-dup calls to show() in the caller. This
23 * is subtly different from the "revision.h:SHOWN" and the
24 * "sha1-name.c:ONELINE_SEEN" bits. And also different from
25 * the non-de-dup usage in pack-bitmap.c
26 */
27 #define FILTER_SHOWN_BUT_REVISIT (1<<21)
28
29 /*
30 * A filter for list-objects to omit ALL blobs from the traversal.
31 * And to OPTIONALLY collect a list of the omitted OIDs.
32 */
33 struct filter_blobs_none_data {
34 struct oidset *omits;
35 };
36
37 static enum list_objects_filter_result filter_blobs_none(
38 struct repository *r,
39 enum list_objects_filter_situation filter_situation,
40 struct object *obj,
41 const char *pathname,
42 const char *filename,
43 void *filter_data_)
44 {
45 struct filter_blobs_none_data *filter_data = filter_data_;
46
47 switch (filter_situation) {
48 default:
49 BUG("unknown filter_situation: %d", filter_situation);
50
51 case LOFS_BEGIN_TREE:
52 assert(obj->type == OBJ_TREE);
53 /* always include all tree objects */
54 return LOFR_MARK_SEEN | LOFR_DO_SHOW;
55
56 case LOFS_END_TREE:
57 assert(obj->type == OBJ_TREE);
58 return LOFR_ZERO;
59
60 case LOFS_BLOB:
61 assert(obj->type == OBJ_BLOB);
62 assert((obj->flags & SEEN) == 0);
63
64 if (filter_data->omits)
65 oidset_insert(filter_data->omits, &obj->oid);
66 return LOFR_MARK_SEEN; /* but not LOFR_DO_SHOW (hard omit) */
67 }
68 }
69
70 static void *filter_blobs_none__init(
71 struct oidset *omitted,
72 struct list_objects_filter_options *filter_options,
73 filter_object_fn *filter_fn,
74 filter_free_fn *filter_free_fn)
75 {
76 struct filter_blobs_none_data *d = xcalloc(1, sizeof(*d));
77 d->omits = omitted;
78
79 *filter_fn = filter_blobs_none;
80 *filter_free_fn = free;
81 return d;
82 }
83
84 /*
85 * A filter for list-objects to omit ALL trees and blobs from the traversal.
86 * Can OPTIONALLY collect a list of the omitted OIDs.
87 */
88 struct filter_trees_depth_data {
89 struct oidset *omits;
90
91 /*
92 * Maps trees to the minimum depth at which they were seen. It is not
93 * necessary to re-traverse a tree at deeper or equal depths than it has
94 * already been traversed.
95 *
96 * We can't use LOFR_MARK_SEEN for tree objects since this will prevent
97 * it from being traversed at shallower depths.
98 */
99 struct oidmap seen_at_depth;
100
101 unsigned long exclude_depth;
102 unsigned long current_depth;
103 };
104
105 struct seen_map_entry {
106 struct oidmap_entry base;
107 size_t depth;
108 };
109
110 /* Returns 1 if the oid was in the omits set before it was invoked. */
111 static int filter_trees_update_omits(
112 struct object *obj,
113 struct filter_trees_depth_data *filter_data,
114 int include_it)
115 {
116 if (!filter_data->omits)
117 return 0;
118
119 if (include_it)
120 return oidset_remove(filter_data->omits, &obj->oid);
121 else
122 return oidset_insert(filter_data->omits, &obj->oid);
123 }
124
125 static enum list_objects_filter_result filter_trees_depth(
126 struct repository *r,
127 enum list_objects_filter_situation filter_situation,
128 struct object *obj,
129 const char *pathname,
130 const char *filename,
131 void *filter_data_)
132 {
133 struct filter_trees_depth_data *filter_data = filter_data_;
134 struct seen_map_entry *seen_info;
135 int include_it = filter_data->current_depth <
136 filter_data->exclude_depth;
137 int filter_res;
138 int already_seen;
139
140 /*
141 * Note that we do not use _MARK_SEEN in order to allow re-traversal in
142 * case we encounter a tree or blob again at a shallower depth.
143 */
144
145 switch (filter_situation) {
146 default:
147 BUG("unknown filter_situation: %d", filter_situation);
148
149 case LOFS_END_TREE:
150 assert(obj->type == OBJ_TREE);
151 filter_data->current_depth--;
152 return LOFR_ZERO;
153
154 case LOFS_BLOB:
155 filter_trees_update_omits(obj, filter_data, include_it);
156 return include_it ? LOFR_MARK_SEEN | LOFR_DO_SHOW : LOFR_ZERO;
157
158 case LOFS_BEGIN_TREE:
159 seen_info = oidmap_get(
160 &filter_data->seen_at_depth, &obj->oid);
161 if (!seen_info) {
162 seen_info = xcalloc(1, sizeof(*seen_info));
163 oidcpy(&seen_info->base.oid, &obj->oid);
164 seen_info->depth = filter_data->current_depth;
165 oidmap_put(&filter_data->seen_at_depth, seen_info);
166 already_seen = 0;
167 } else {
168 already_seen =
169 filter_data->current_depth >= seen_info->depth;
170 }
171
172 if (already_seen) {
173 filter_res = LOFR_SKIP_TREE;
174 } else {
175 int been_omitted = filter_trees_update_omits(
176 obj, filter_data, include_it);
177 seen_info->depth = filter_data->current_depth;
178
179 if (include_it)
180 filter_res = LOFR_DO_SHOW;
181 else if (filter_data->omits && !been_omitted)
182 /*
183 * Must update omit information of children
184 * recursively; they have not been omitted yet.
185 */
186 filter_res = LOFR_ZERO;
187 else
188 filter_res = LOFR_SKIP_TREE;
189 }
190
191 filter_data->current_depth++;
192 return filter_res;
193 }
194 }
195
196 static void filter_trees_free(void *filter_data) {
197 struct filter_trees_depth_data *d = filter_data;
198 if (!d)
199 return;
200 oidmap_free(&d->seen_at_depth, 1);
201 free(d);
202 }
203
204 static void *filter_trees_depth__init(
205 struct oidset *omitted,
206 struct list_objects_filter_options *filter_options,
207 filter_object_fn *filter_fn,
208 filter_free_fn *filter_free_fn)
209 {
210 struct filter_trees_depth_data *d = xcalloc(1, sizeof(*d));
211 d->omits = omitted;
212 oidmap_init(&d->seen_at_depth, 0);
213 d->exclude_depth = filter_options->tree_exclude_depth;
214 d->current_depth = 0;
215
216 *filter_fn = filter_trees_depth;
217 *filter_free_fn = filter_trees_free;
218 return d;
219 }
220
221 /*
222 * A filter for list-objects to omit large blobs.
223 * And to OPTIONALLY collect a list of the omitted OIDs.
224 */
225 struct filter_blobs_limit_data {
226 struct oidset *omits;
227 unsigned long max_bytes;
228 };
229
230 static enum list_objects_filter_result filter_blobs_limit(
231 struct repository *r,
232 enum list_objects_filter_situation filter_situation,
233 struct object *obj,
234 const char *pathname,
235 const char *filename,
236 void *filter_data_)
237 {
238 struct filter_blobs_limit_data *filter_data = filter_data_;
239 unsigned long object_length;
240 enum object_type t;
241
242 switch (filter_situation) {
243 default:
244 BUG("unknown filter_situation: %d", filter_situation);
245
246 case LOFS_BEGIN_TREE:
247 assert(obj->type == OBJ_TREE);
248 /* always include all tree objects */
249 return LOFR_MARK_SEEN | LOFR_DO_SHOW;
250
251 case LOFS_END_TREE:
252 assert(obj->type == OBJ_TREE);
253 return LOFR_ZERO;
254
255 case LOFS_BLOB:
256 assert(obj->type == OBJ_BLOB);
257 assert((obj->flags & SEEN) == 0);
258
259 t = oid_object_info(r, &obj->oid, &object_length);
260 if (t != OBJ_BLOB) { /* probably OBJ_NONE */
261 /*
262 * We DO NOT have the blob locally, so we cannot
263 * apply the size filter criteria. Be conservative
264 * and force show it (and let the caller deal with
265 * the ambiguity).
266 */
267 goto include_it;
268 }
269
270 if (object_length < filter_data->max_bytes)
271 goto include_it;
272
273 if (filter_data->omits)
274 oidset_insert(filter_data->omits, &obj->oid);
275 return LOFR_MARK_SEEN; /* but not LOFR_DO_SHOW (hard omit) */
276 }
277
278 include_it:
279 if (filter_data->omits)
280 oidset_remove(filter_data->omits, &obj->oid);
281 return LOFR_MARK_SEEN | LOFR_DO_SHOW;
282 }
283
284 static void *filter_blobs_limit__init(
285 struct oidset *omitted,
286 struct list_objects_filter_options *filter_options,
287 filter_object_fn *filter_fn,
288 filter_free_fn *filter_free_fn)
289 {
290 struct filter_blobs_limit_data *d = xcalloc(1, sizeof(*d));
291 d->omits = omitted;
292 d->max_bytes = filter_options->blob_limit_value;
293
294 *filter_fn = filter_blobs_limit;
295 *filter_free_fn = free;
296 return d;
297 }
298
299 /*
300 * A filter driven by a sparse-checkout specification to only
301 * include blobs that a sparse checkout would populate.
302 *
303 * The sparse-checkout spec can be loaded from a blob with the
304 * given OID or from a local pathname. We allow an OID because
305 * the repo may be bare or we may be doing the filtering on the
306 * server.
307 */
308 struct frame {
309 /*
310 * defval is the usual default include/exclude value that
311 * should be inherited as we recurse into directories based
312 * upon pattern matching of the directory itself or of a
313 * containing directory.
314 */
315 int defval;
316
317 /*
318 * 1 if the directory (recursively) contains any provisionally
319 * omitted objects.
320 *
321 * 0 if everything (recursively) contained in this directory
322 * has been explicitly included (SHOWN) in the result and
323 * the directory may be short-cut later in the traversal.
324 */
325 unsigned child_prov_omit : 1;
326 };
327
328 struct filter_sparse_data {
329 struct oidset *omits;
330 struct exclude_list el;
331
332 size_t nr, alloc;
333 struct frame *array_frame;
334 };
335
336 static enum list_objects_filter_result filter_sparse(
337 struct repository *r,
338 enum list_objects_filter_situation filter_situation,
339 struct object *obj,
340 const char *pathname,
341 const char *filename,
342 void *filter_data_)
343 {
344 struct filter_sparse_data *filter_data = filter_data_;
345 int val, dtype;
346 struct frame *frame;
347
348 switch (filter_situation) {
349 default:
350 BUG("unknown filter_situation: %d", filter_situation);
351
352 case LOFS_BEGIN_TREE:
353 assert(obj->type == OBJ_TREE);
354 dtype = DT_DIR;
355 val = is_excluded_from_list(pathname, strlen(pathname),
356 filename, &dtype, &filter_data->el,
357 r->index);
358 if (val < 0)
359 val = filter_data->array_frame[filter_data->nr - 1].defval;
360
361 ALLOC_GROW(filter_data->array_frame, filter_data->nr + 1,
362 filter_data->alloc);
363 filter_data->array_frame[filter_data->nr].defval = val;
364 filter_data->array_frame[filter_data->nr].child_prov_omit = 0;
365 filter_data->nr++;
366
367 /*
368 * A directory with this tree OID may appear in multiple
369 * places in the tree. (Think of a directory move or copy,
370 * with no other changes, so the OID is the same, but the
371 * full pathnames of objects within this directory are new
372 * and may match is_excluded() patterns differently.)
373 * So we cannot mark this directory as SEEN (yet), since
374 * that will prevent process_tree() from revisiting this
375 * tree object with other pathname prefixes.
376 *
377 * Only _DO_SHOW the tree object the first time we visit
378 * this tree object.
379 *
380 * We always show all tree objects. A future optimization
381 * may want to attempt to narrow this.
382 */
383 if (obj->flags & FILTER_SHOWN_BUT_REVISIT)
384 return LOFR_ZERO;
385 obj->flags |= FILTER_SHOWN_BUT_REVISIT;
386 return LOFR_DO_SHOW;
387
388 case LOFS_END_TREE:
389 assert(obj->type == OBJ_TREE);
390 assert(filter_data->nr > 1);
391
392 frame = &filter_data->array_frame[--filter_data->nr];
393
394 /*
395 * Tell our parent directory if any of our children were
396 * provisionally omitted.
397 */
398 filter_data->array_frame[filter_data->nr - 1].child_prov_omit |=
399 frame->child_prov_omit;
400
401 /*
402 * If there are NO provisionally omitted child objects (ALL child
403 * objects in this folder were INCLUDED), then we can mark the
404 * folder as SEEN (so we will not have to revisit it again).
405 */
406 if (!frame->child_prov_omit)
407 return LOFR_MARK_SEEN;
408 return LOFR_ZERO;
409
410 case LOFS_BLOB:
411 assert(obj->type == OBJ_BLOB);
412 assert((obj->flags & SEEN) == 0);
413
414 frame = &filter_data->array_frame[filter_data->nr - 1];
415
416 dtype = DT_REG;
417 val = is_excluded_from_list(pathname, strlen(pathname),
418 filename, &dtype, &filter_data->el,
419 r->index);
420 if (val < 0)
421 val = frame->defval;
422 if (val > 0) {
423 if (filter_data->omits)
424 oidset_remove(filter_data->omits, &obj->oid);
425 return LOFR_MARK_SEEN | LOFR_DO_SHOW;
426 }
427
428 /*
429 * Provisionally omit it. We've already established that
430 * this pathname is not in the sparse-checkout specification
431 * with the CURRENT pathname, so we *WANT* to omit this blob.
432 *
433 * However, a pathname elsewhere in the tree may also
434 * reference this same blob, so we cannot reject it yet.
435 * Leave the LOFR_ bits unset so that if the blob appears
436 * again in the traversal, we will be asked again.
437 */
438 if (filter_data->omits)
439 oidset_insert(filter_data->omits, &obj->oid);
440
441 /*
442 * Remember that at least 1 blob in this tree was
443 * provisionally omitted. This prevents us from short
444 * cutting the tree in future iterations.
445 */
446 frame->child_prov_omit = 1;
447 return LOFR_ZERO;
448 }
449 }
450
451
452 static void filter_sparse_free(void *filter_data)
453 {
454 struct filter_sparse_data *d = filter_data;
455 free(d->array_frame);
456 free(d);
457 }
458
459 static void *filter_sparse_oid__init(
460 struct oidset *omitted,
461 struct list_objects_filter_options *filter_options,
462 filter_object_fn *filter_fn,
463 filter_free_fn *filter_free_fn)
464 {
465 struct filter_sparse_data *d = xcalloc(1, sizeof(*d));
466 d->omits = omitted;
467 if (add_excludes_from_blob_to_list(filter_options->sparse_oid_value,
468 NULL, 0, &d->el) < 0)
469 die("could not load filter specification");
470
471 ALLOC_GROW(d->array_frame, d->nr + 1, d->alloc);
472 d->array_frame[d->nr].defval = 0; /* default to include */
473 d->array_frame[d->nr].child_prov_omit = 0;
474 d->nr++;
475
476 *filter_fn = filter_sparse;
477 *filter_free_fn = filter_sparse_free;
478 return d;
479 }
480
481 typedef void *(*filter_init_fn)(
482 struct oidset *omitted,
483 struct list_objects_filter_options *filter_options,
484 filter_object_fn *filter_fn,
485 filter_free_fn *filter_free_fn);
486
487 /*
488 * Must match "enum list_objects_filter_choice".
489 */
490 static filter_init_fn s_filters[] = {
491 NULL,
492 filter_blobs_none__init,
493 filter_blobs_limit__init,
494 filter_trees_depth__init,
495 filter_sparse_oid__init,
496 };
497
498 void *list_objects_filter__init(
499 struct oidset *omitted,
500 struct list_objects_filter_options *filter_options,
501 filter_object_fn *filter_fn,
502 filter_free_fn *filter_free_fn)
503 {
504 filter_init_fn init_fn;
505
506 assert((sizeof(s_filters) / sizeof(s_filters[0])) == LOFC__COUNT);
507
508 if (filter_options->choice >= LOFC__COUNT)
509 BUG("invalid list-objects filter choice: %d",
510 filter_options->choice);
511
512 init_fn = s_filters[filter_options->choice];
513 if (init_fn)
514 return init_fn(omitted, filter_options,
515 filter_fn, filter_free_fn);
516 *filter_fn = NULL;
517 *filter_free_fn = NULL;
518 return NULL;
519 }