msvc: add pragmas for common warnings
[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].defval;
360
361                 ALLOC_GROW(filter_data->array_frame, filter_data->nr + 1,
362                            filter_data->alloc);
363                 filter_data->nr++;
364                 filter_data->array_frame[filter_data->nr].defval = val;
365                 filter_data->array_frame[filter_data->nr].child_prov_omit = 0;
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 > 0);
391
392                 frame = &filter_data->array_frame[filter_data->nr];
393                 filter_data->nr--;
394
395                 /*
396                  * Tell our parent directory if any of our children were
397                  * provisionally omitted.
398                  */
399                 filter_data->array_frame[filter_data->nr].child_prov_omit |=
400                         frame->child_prov_omit;
401
402                 /*
403                  * If there are NO provisionally omitted child objects (ALL child
404                  * objects in this folder were INCLUDED), then we can mark the
405                  * folder as SEEN (so we will not have to revisit it again).
406                  */
407                 if (!frame->child_prov_omit)
408                         return LOFR_MARK_SEEN;
409                 return LOFR_ZERO;
410
411         case LOFS_BLOB:
412                 assert(obj->type == OBJ_BLOB);
413                 assert((obj->flags & SEEN) == 0);
414
415                 frame = &filter_data->array_frame[filter_data->nr];
416
417                 dtype = DT_REG;
418                 val = is_excluded_from_list(pathname, strlen(pathname),
419                                             filename, &dtype, &filter_data->el,
420                                             r->index);
421                 if (val < 0)
422                         val = frame->defval;
423                 if (val > 0) {
424                         if (filter_data->omits)
425                                 oidset_remove(filter_data->omits, &obj->oid);
426                         return LOFR_MARK_SEEN | LOFR_DO_SHOW;
427                 }
428
429                 /*
430                  * Provisionally omit it.  We've already established that
431                  * this pathname is not in the sparse-checkout specification
432                  * with the CURRENT pathname, so we *WANT* to omit this blob.
433                  *
434                  * However, a pathname elsewhere in the tree may also
435                  * reference this same blob, so we cannot reject it yet.
436                  * Leave the LOFR_ bits unset so that if the blob appears
437                  * again in the traversal, we will be asked again.
438                  */
439                 if (filter_data->omits)
440                         oidset_insert(filter_data->omits, &obj->oid);
441
442                 /*
443                  * Remember that at least 1 blob in this tree was
444                  * provisionally omitted.  This prevents us from short
445                  * cutting the tree in future iterations.
446                  */
447                 frame->child_prov_omit = 1;
448                 return LOFR_ZERO;
449         }
450 }
451
452
453 static void filter_sparse_free(void *filter_data)
454 {
455         struct filter_sparse_data *d = filter_data;
456         /* TODO free contents of 'd' */
457         free(d);
458 }
459
460 static void *filter_sparse_oid__init(
461         struct oidset *omitted,
462         struct list_objects_filter_options *filter_options,
463         filter_object_fn *filter_fn,
464         filter_free_fn *filter_free_fn)
465 {
466         struct filter_sparse_data *d = xcalloc(1, sizeof(*d));
467         d->omits = omitted;
468         if (add_excludes_from_blob_to_list(filter_options->sparse_oid_value,
469                                            NULL, 0, &d->el) < 0)
470                 die("could not load filter specification");
471
472         ALLOC_GROW(d->array_frame, d->nr + 1, d->alloc);
473         d->array_frame[d->nr].defval = 0; /* default to include */
474         d->array_frame[d->nr].child_prov_omit = 0;
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 }