pack-objects: further work on internal rev-list logic.
[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 "list-objects.h"
11 #include "builtin.h"
12
13 /* bits #0-15 in revision.h */
14
15 #define COUNTED         (1u<<16)
16
17 static const char rev_list_usage[] =
18 "git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
19 "  limiting output:\n"
20 "    --max-count=nr\n"
21 "    --max-age=epoch\n"
22 "    --min-age=epoch\n"
23 "    --sparse\n"
24 "    --no-merges\n"
25 "    --remove-empty\n"
26 "    --all\n"
27 "    --stdin\n"
28 "  ordering output:\n"
29 "    --topo-order\n"
30 "    --date-order\n"
31 "  formatting output:\n"
32 "    --parents\n"
33 "    --objects | --objects-edge\n"
34 "    --unpacked\n"
35 "    --header | --pretty\n"
36 "    --abbrev=nr | --no-abbrev\n"
37 "    --abbrev-commit\n"
38 "  special purpose:\n"
39 "    --bisect"
40 ;
41
42 static struct rev_info revs;
43
44 static int bisect_list;
45 static int show_timestamp;
46 static int hdr_termination;
47 static const char *header_prefix;
48
49 static void show_commit(struct commit *commit)
50 {
51         if (show_timestamp)
52                 printf("%lu ", commit->date);
53         if (header_prefix)
54                 fputs(header_prefix, stdout);
55         if (commit->object.flags & BOUNDARY)
56                 putchar('-');
57         if (revs.abbrev_commit && revs.abbrev)
58                 fputs(find_unique_abbrev(commit->object.sha1, revs.abbrev),
59                       stdout);
60         else
61                 fputs(sha1_to_hex(commit->object.sha1), stdout);
62         if (revs.parents) {
63                 struct commit_list *parents = commit->parents;
64                 while (parents) {
65                         struct object *o = &(parents->item->object);
66                         parents = parents->next;
67                         if (o->flags & TMP_MARK)
68                                 continue;
69                         printf(" %s", sha1_to_hex(o->sha1));
70                         o->flags |= TMP_MARK;
71                 }
72                 /* TMP_MARK is a general purpose flag that can
73                  * be used locally, but the user should clean
74                  * things up after it is done with them.
75                  */
76                 for (parents = commit->parents;
77                      parents;
78                      parents = parents->next)
79                         parents->item->object.flags &= ~TMP_MARK;
80         }
81         if (revs.commit_format == CMIT_FMT_ONELINE)
82                 putchar(' ');
83         else
84                 putchar('\n');
85
86         if (revs.verbose_header) {
87                 static char pretty_header[16384];
88                 pretty_print_commit(revs.commit_format, commit, ~0,
89                                     pretty_header, sizeof(pretty_header),
90                                     revs.abbrev, NULL, NULL, revs.relative_date);
91                 printf("%s%c", pretty_header, hdr_termination);
92         }
93         fflush(stdout);
94         if (commit->parents) {
95                 free_commit_list(commit->parents);
96                 commit->parents = NULL;
97         }
98         free(commit->buffer);
99         commit->buffer = NULL;
100 }
101
102 static void show_object(struct object_array_entry *p)
103 {
104         /* An object with name "foo\n0000000..." can be used to
105          * confuse downstream git-pack-objects very badly.
106          */
107         const char *ep = strchr(p->name, '\n');
108         if (ep) {
109                 printf("%s %.*s\n", sha1_to_hex(p->item->sha1),
110                        (int) (ep - p->name),
111                        p->name);
112         }
113         else
114                 printf("%s %s\n", sha1_to_hex(p->item->sha1), p->name);
115 }
116
117 static void show_edge(struct commit *commit)
118 {
119         printf("-%s\n", sha1_to_hex(commit->object.sha1));
120 }
121
122 /*
123  * This is a truly stupid algorithm, but it's only
124  * used for bisection, and we just don't care enough.
125  *
126  * We care just barely enough to avoid recursing for
127  * non-merge entries.
128  */
129 static int count_distance(struct commit_list *entry)
130 {
131         int nr = 0;
132
133         while (entry) {
134                 struct commit *commit = entry->item;
135                 struct commit_list *p;
136
137                 if (commit->object.flags & (UNINTERESTING | COUNTED))
138                         break;
139                 if (!revs.prune_fn || (commit->object.flags & TREECHANGE))
140                         nr++;
141                 commit->object.flags |= COUNTED;
142                 p = commit->parents;
143                 entry = p;
144                 if (p) {
145                         p = p->next;
146                         while (p) {
147                                 nr += count_distance(p);
148                                 p = p->next;
149                         }
150                 }
151         }
152
153         return nr;
154 }
155
156 static void clear_distance(struct commit_list *list)
157 {
158         while (list) {
159                 struct commit *commit = list->item;
160                 commit->object.flags &= ~COUNTED;
161                 list = list->next;
162         }
163 }
164
165 static struct commit_list *find_bisection(struct commit_list *list)
166 {
167         int nr, closest;
168         struct commit_list *p, *best;
169
170         nr = 0;
171         p = list;
172         while (p) {
173                 if (!revs.prune_fn || (p->item->object.flags & TREECHANGE))
174                         nr++;
175                 p = p->next;
176         }
177         closest = 0;
178         best = list;
179
180         for (p = list; p; p = p->next) {
181                 int distance;
182
183                 if (revs.prune_fn && !(p->item->object.flags & TREECHANGE))
184                         continue;
185
186                 distance = count_distance(p);
187                 clear_distance(list);
188                 if (nr - distance < distance)
189                         distance = nr - distance;
190                 if (distance > closest) {
191                         best = p;
192                         closest = distance;
193                 }
194         }
195         if (best)
196                 best->next = NULL;
197         return best;
198 }
199
200 static void read_revisions_from_stdin(struct rev_info *revs)
201 {
202         char line[1000];
203
204         while (fgets(line, sizeof(line), stdin) != NULL) {
205                 int len = strlen(line);
206                 if (line[len - 1] == '\n')
207                         line[--len] = 0;
208                 if (!len)
209                         break;
210                 if (line[0] == '-')
211                         die("options not supported in --stdin mode");
212                 if (handle_revision_arg(line, revs, 0, 1))
213                         die("bad revision '%s'", line);
214         }
215 }
216
217 int cmd_rev_list(int argc, const char **argv, const char *prefix)
218 {
219         struct commit_list *list;
220         int i;
221         int read_from_stdin = 0;
222
223         init_revisions(&revs, prefix);
224         revs.abbrev = 0;
225         revs.commit_format = CMIT_FMT_UNSPECIFIED;
226         argc = setup_revisions(argc, argv, &revs, NULL);
227
228         for (i = 1 ; i < argc; i++) {
229                 const char *arg = argv[i];
230
231                 if (!strcmp(arg, "--header")) {
232                         revs.verbose_header = 1;
233                         continue;
234                 }
235                 if (!strcmp(arg, "--timestamp")) {
236                         show_timestamp = 1;
237                         continue;
238                 }
239                 if (!strcmp(arg, "--bisect")) {
240                         bisect_list = 1;
241                         continue;
242                 }
243                 if (!strcmp(arg, "--stdin")) {
244                         if (read_from_stdin++)
245                                 die("--stdin given twice?");
246                         read_revisions_from_stdin(&revs);
247                         continue;
248                 }
249                 usage(rev_list_usage);
250
251         }
252         if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
253                 /* The command line has a --pretty  */
254                 hdr_termination = '\n';
255                 if (revs.commit_format == CMIT_FMT_ONELINE)
256                         header_prefix = "";
257                 else
258                         header_prefix = "commit ";
259         }
260         else if (revs.verbose_header)
261                 /* Only --header was specified */
262                 revs.commit_format = CMIT_FMT_RAW;
263
264         list = revs.commits;
265
266         if ((!list &&
267              (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) &&
268               !revs.pending.nr)) ||
269             revs.diff)
270                 usage(rev_list_usage);
271
272         save_commit_buffer = revs.verbose_header;
273         track_object_refs = 0;
274         if (bisect_list)
275                 revs.limited = 1;
276
277         prepare_revision_walk(&revs);
278         if (revs.tree_objects)
279                 mark_edges_uninteresting(revs.commits, &revs, show_edge);
280
281         if (bisect_list)
282                 revs.commits = find_bisection(revs.commits);
283
284         traverse_commit_list(&revs, show_commit, show_object);
285
286         return 0;
287 }