Racy GIT (part #3)
[git] / builtin-rev-list.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "tag.h"
4 #include "commit.h"
5 #include "tree.h"
6 #include "blob.h"
7 #include "tree-walk.h"
8 #include "diff.h"
9 #include "revision.h"
10 #include "builtin.h"
11
12 /* bits #0-15 in revision.h */
13
14 #define COUNTED         (1u<<16)
15
16 static const char rev_list_usage[] =
17 "git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
18 "  limiting output:\n"
19 "    --max-count=nr\n"
20 "    --max-age=epoch\n"
21 "    --min-age=epoch\n"
22 "    --sparse\n"
23 "    --no-merges\n"
24 "    --remove-empty\n"
25 "    --all\n"
26 "  ordering output:\n"
27 "    --topo-order\n"
28 "    --date-order\n"
29 "  formatting output:\n"
30 "    --parents\n"
31 "    --objects | --objects-edge\n"
32 "    --unpacked\n"
33 "    --header | --pretty\n"
34 "    --abbrev=nr | --no-abbrev\n"
35 "    --abbrev-commit\n"
36 "  special purpose:\n"
37 "    --bisect"
38 ;
39
40 static struct rev_info revs;
41
42 static int bisect_list = 0;
43 static int show_timestamp = 0;
44 static int hdr_termination = 0;
45 static const char *header_prefix;
46
47 static void show_commit(struct commit *commit)
48 {
49         if (show_timestamp)
50                 printf("%lu ", commit->date);
51         if (header_prefix)
52                 fputs(header_prefix, stdout);
53         if (commit->object.flags & BOUNDARY)
54                 putchar('-');
55         if (revs.abbrev_commit && revs.abbrev)
56                 fputs(find_unique_abbrev(commit->object.sha1, revs.abbrev),
57                       stdout);
58         else
59                 fputs(sha1_to_hex(commit->object.sha1), stdout);
60         if (revs.parents) {
61                 struct commit_list *parents = commit->parents;
62                 while (parents) {
63                         struct object *o = &(parents->item->object);
64                         parents = parents->next;
65                         if (o->flags & TMP_MARK)
66                                 continue;
67                         printf(" %s", sha1_to_hex(o->sha1));
68                         o->flags |= TMP_MARK;
69                 }
70                 /* TMP_MARK is a general purpose flag that can
71                  * be used locally, but the user should clean
72                  * things up after it is done with them.
73                  */
74                 for (parents = commit->parents;
75                      parents;
76                      parents = parents->next)
77                         parents->item->object.flags &= ~TMP_MARK;
78         }
79         if (revs.commit_format == CMIT_FMT_ONELINE)
80                 putchar(' ');
81         else
82                 putchar('\n');
83
84         if (revs.verbose_header) {
85                 static char pretty_header[16384];
86                 pretty_print_commit(revs.commit_format, commit, ~0,
87                                     pretty_header, sizeof(pretty_header),
88                                     revs.abbrev, NULL, NULL);
89                 printf("%s%c", pretty_header, hdr_termination);
90         }
91         fflush(stdout);
92         if (commit->parents) {
93                 free_commit_list(commit->parents);
94                 commit->parents = NULL;
95         }
96         if (commit->buffer) {
97                 free(commit->buffer);
98                 commit->buffer = NULL;
99         }
100 }
101
102 static void process_blob(struct blob *blob,
103                          struct object_array *p,
104                          struct name_path *path,
105                          const char *name)
106 {
107         struct object *obj = &blob->object;
108
109         if (!revs.blob_objects)
110                 return;
111         if (obj->flags & (UNINTERESTING | SEEN))
112                 return;
113         obj->flags |= SEEN;
114         name = strdup(name);
115         add_object(obj, p, path, name);
116 }
117
118 static void process_tree(struct tree *tree,
119                          struct object_array *p,
120                          struct name_path *path,
121                          const char *name)
122 {
123         struct object *obj = &tree->object;
124         struct tree_desc desc;
125         struct name_entry entry;
126         struct name_path me;
127
128         if (!revs.tree_objects)
129                 return;
130         if (obj->flags & (UNINTERESTING | SEEN))
131                 return;
132         if (parse_tree(tree) < 0)
133                 die("bad tree object %s", sha1_to_hex(obj->sha1));
134         obj->flags |= SEEN;
135         name = strdup(name);
136         add_object(obj, p, path, name);
137         me.up = path;
138         me.elem = name;
139         me.elem_len = strlen(name);
140
141         desc.buf = tree->buffer;
142         desc.size = tree->size;
143
144         while (tree_entry(&desc, &entry)) {
145                 if (S_ISDIR(entry.mode))
146                         process_tree(lookup_tree(entry.sha1), p, &me, entry.path);
147                 else
148                         process_blob(lookup_blob(entry.sha1), p, &me, entry.path);
149         }
150         free(tree->buffer);
151         tree->buffer = NULL;
152 }
153
154 static void show_commit_list(struct rev_info *revs)
155 {
156         int i;
157         struct commit *commit;
158         struct object_array objects = { 0, 0, NULL };
159
160         while ((commit = get_revision(revs)) != NULL) {
161                 process_tree(commit->tree, &objects, NULL, "");
162                 show_commit(commit);
163         }
164         for (i = 0; i < revs->pending.nr; i++) {
165                 struct object_array_entry *pending = revs->pending.objects + i;
166                 struct object *obj = pending->item;
167                 const char *name = pending->name;
168                 if (obj->flags & (UNINTERESTING | SEEN))
169                         continue;
170                 if (obj->type == TYPE_TAG) {
171                         obj->flags |= SEEN;
172                         add_object_array(obj, name, &objects);
173                         continue;
174                 }
175                 if (obj->type == TYPE_TREE) {
176                         process_tree((struct tree *)obj, &objects, NULL, name);
177                         continue;
178                 }
179                 if (obj->type == TYPE_BLOB) {
180                         process_blob((struct blob *)obj, &objects, NULL, name);
181                         continue;
182                 }
183                 die("unknown pending object %s (%s)", sha1_to_hex(obj->sha1), name);
184         }
185         for (i = 0; i < objects.nr; i++) {
186                 struct object_array_entry *p = objects.objects + i;
187
188                 /* An object with name "foo\n0000000..." can be used to
189                  * confuse downstream git-pack-objects very badly.
190                  */
191                 const char *ep = strchr(p->name, '\n');
192                 if (ep) {
193                         printf("%s %.*s\n", sha1_to_hex(p->item->sha1),
194                                (int) (ep - p->name),
195                                p->name);
196                 }
197                 else
198                         printf("%s %s\n", sha1_to_hex(p->item->sha1), p->name);
199         }
200 }
201
202 /*
203  * This is a truly stupid algorithm, but it's only
204  * used for bisection, and we just don't care enough.
205  *
206  * We care just barely enough to avoid recursing for
207  * non-merge entries.
208  */
209 static int count_distance(struct commit_list *entry)
210 {
211         int nr = 0;
212
213         while (entry) {
214                 struct commit *commit = entry->item;
215                 struct commit_list *p;
216
217                 if (commit->object.flags & (UNINTERESTING | COUNTED))
218                         break;
219                 if (!revs.prune_fn || (commit->object.flags & TREECHANGE))
220                         nr++;
221                 commit->object.flags |= COUNTED;
222                 p = commit->parents;
223                 entry = p;
224                 if (p) {
225                         p = p->next;
226                         while (p) {
227                                 nr += count_distance(p);
228                                 p = p->next;
229                         }
230                 }
231         }
232
233         return nr;
234 }
235
236 static void clear_distance(struct commit_list *list)
237 {
238         while (list) {
239                 struct commit *commit = list->item;
240                 commit->object.flags &= ~COUNTED;
241                 list = list->next;
242         }
243 }
244
245 static struct commit_list *find_bisection(struct commit_list *list)
246 {
247         int nr, closest;
248         struct commit_list *p, *best;
249
250         nr = 0;
251         p = list;
252         while (p) {
253                 if (!revs.prune_fn || (p->item->object.flags & TREECHANGE))
254                         nr++;
255                 p = p->next;
256         }
257         closest = 0;
258         best = list;
259
260         for (p = list; p; p = p->next) {
261                 int distance;
262
263                 if (revs.prune_fn && !(p->item->object.flags & TREECHANGE))
264                         continue;
265
266                 distance = count_distance(p);
267                 clear_distance(list);
268                 if (nr - distance < distance)
269                         distance = nr - distance;
270                 if (distance > closest) {
271                         best = p;
272                         closest = distance;
273                 }
274         }
275         if (best)
276                 best->next = NULL;
277         return best;
278 }
279
280 static void mark_edge_parents_uninteresting(struct commit *commit)
281 {
282         struct commit_list *parents;
283
284         for (parents = commit->parents; parents; parents = parents->next) {
285                 struct commit *parent = parents->item;
286                 if (!(parent->object.flags & UNINTERESTING))
287                         continue;
288                 mark_tree_uninteresting(parent->tree);
289                 if (revs.edge_hint && !(parent->object.flags & SHOWN)) {
290                         parent->object.flags |= SHOWN;
291                         printf("-%s\n", sha1_to_hex(parent->object.sha1));
292                 }
293         }
294 }
295
296 static void mark_edges_uninteresting(struct commit_list *list)
297 {
298         for ( ; list; list = list->next) {
299                 struct commit *commit = list->item;
300
301                 if (commit->object.flags & UNINTERESTING) {
302                         mark_tree_uninteresting(commit->tree);
303                         continue;
304                 }
305                 mark_edge_parents_uninteresting(commit);
306         }
307 }
308
309 int cmd_rev_list(int argc, const char **argv, char **envp)
310 {
311         struct commit_list *list;
312         int i;
313
314         init_revisions(&revs);
315         revs.abbrev = 0;
316         revs.commit_format = CMIT_FMT_UNSPECIFIED;
317         argc = setup_revisions(argc, argv, &revs, NULL);
318
319         for (i = 1 ; i < argc; i++) {
320                 const char *arg = argv[i];
321
322                 if (!strcmp(arg, "--header")) {
323                         revs.verbose_header = 1;
324                         continue;
325                 }
326                 if (!strcmp(arg, "--timestamp")) {
327                         show_timestamp = 1;
328                         continue;
329                 }
330                 if (!strcmp(arg, "--bisect")) {
331                         bisect_list = 1;
332                         continue;
333                 }
334                 usage(rev_list_usage);
335
336         }
337         if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
338                 /* The command line has a --pretty  */
339                 hdr_termination = '\n';
340                 if (revs.commit_format == CMIT_FMT_ONELINE)
341                         header_prefix = "";
342                 else
343                         header_prefix = "commit ";
344         }
345         else if (revs.verbose_header)
346                 /* Only --header was specified */
347                 revs.commit_format = CMIT_FMT_RAW;
348
349         list = revs.commits;
350
351         if ((!list &&
352              (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) &&
353               !revs.pending.nr)) ||
354             revs.diff)
355                 usage(rev_list_usage);
356
357         save_commit_buffer = revs.verbose_header;
358         track_object_refs = 0;
359         if (bisect_list)
360                 revs.limited = 1;
361
362         prepare_revision_walk(&revs);
363         if (revs.tree_objects)
364                 mark_edges_uninteresting(revs.commits);
365
366         if (bisect_list)
367                 revs.commits = find_bisection(revs.commits);
368
369         show_commit_list(&revs);
370
371         return 0;
372 }