Fix documentation grammar typo
[git] / builtin-rev-list.c
1 #include "cache.h"
2 #include "commit.h"
3 #include "diff.h"
4 #include "revision.h"
5 #include "list-objects.h"
6 #include "builtin.h"
7 #include "log-tree.h"
8 #include "graph.h"
9 #include "bisect.h"
10
11 static const char rev_list_usage[] =
12 "git rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
13 "  limiting output:\n"
14 "    --max-count=nr\n"
15 "    --max-age=epoch\n"
16 "    --min-age=epoch\n"
17 "    --sparse\n"
18 "    --no-merges\n"
19 "    --remove-empty\n"
20 "    --all\n"
21 "    --branches\n"
22 "    --tags\n"
23 "    --remotes\n"
24 "    --stdin\n"
25 "    --quiet\n"
26 "  ordering output:\n"
27 "    --topo-order\n"
28 "    --date-order\n"
29 "    --reverse\n"
30 "  formatting output:\n"
31 "    --parents\n"
32 "    --children\n"
33 "    --objects | --objects-edge\n"
34 "    --unpacked\n"
35 "    --header | --pretty\n"
36 "    --abbrev=nr | --no-abbrev\n"
37 "    --abbrev-commit\n"
38 "    --left-right\n"
39 "  special purpose:\n"
40 "    --bisect\n"
41 "    --bisect-vars\n"
42 "    --bisect-all"
43 ;
44
45 static void finish_commit(struct commit *commit, void *data);
46 static void show_commit(struct commit *commit, void *data)
47 {
48         struct rev_list_info *info = data;
49         struct rev_info *revs = info->revs;
50
51         graph_show_commit(revs->graph);
52
53         if (info->show_timestamp)
54                 printf("%lu ", commit->date);
55         if (info->header_prefix)
56                 fputs(info->header_prefix, stdout);
57
58         if (!revs->graph) {
59                 if (commit->object.flags & BOUNDARY)
60                         putchar('-');
61                 else if (commit->object.flags & UNINTERESTING)
62                         putchar('^');
63                 else if (revs->left_right) {
64                         if (commit->object.flags & SYMMETRIC_LEFT)
65                                 putchar('<');
66                         else
67                                 putchar('>');
68                 }
69         }
70         if (revs->abbrev_commit && revs->abbrev)
71                 fputs(find_unique_abbrev(commit->object.sha1, revs->abbrev),
72                       stdout);
73         else
74                 fputs(sha1_to_hex(commit->object.sha1), stdout);
75         if (revs->print_parents) {
76                 struct commit_list *parents = commit->parents;
77                 while (parents) {
78                         printf(" %s", sha1_to_hex(parents->item->object.sha1));
79                         parents = parents->next;
80                 }
81         }
82         if (revs->children.name) {
83                 struct commit_list *children;
84
85                 children = lookup_decoration(&revs->children, &commit->object);
86                 while (children) {
87                         printf(" %s", sha1_to_hex(children->item->object.sha1));
88                         children = children->next;
89                 }
90         }
91         show_decorations(revs, commit);
92         if (revs->commit_format == CMIT_FMT_ONELINE)
93                 putchar(' ');
94         else
95                 putchar('\n');
96
97         if (revs->verbose_header && commit->buffer) {
98                 struct strbuf buf = STRBUF_INIT;
99                 pretty_print_commit(revs->commit_format, commit,
100                                     &buf, revs->abbrev, NULL, NULL,
101                                     revs->date_mode, 0);
102                 if (revs->graph) {
103                         if (buf.len) {
104                                 if (revs->commit_format != CMIT_FMT_ONELINE)
105                                         graph_show_oneline(revs->graph);
106
107                                 graph_show_commit_msg(revs->graph, &buf);
108
109                                 /*
110                                  * Add a newline after the commit message.
111                                  *
112                                  * Usually, this newline produces a blank
113                                  * padding line between entries, in which case
114                                  * we need to add graph padding on this line.
115                                  *
116                                  * However, the commit message may not end in a
117                                  * newline.  In this case the newline simply
118                                  * ends the last line of the commit message,
119                                  * and we don't need any graph output.  (This
120                                  * always happens with CMIT_FMT_ONELINE, and it
121                                  * happens with CMIT_FMT_USERFORMAT when the
122                                  * format doesn't explicitly end in a newline.)
123                                  */
124                                 if (buf.len && buf.buf[buf.len - 1] == '\n')
125                                         graph_show_padding(revs->graph);
126                                 putchar('\n');
127                         } else {
128                                 /*
129                                  * If the message buffer is empty, just show
130                                  * the rest of the graph output for this
131                                  * commit.
132                                  */
133                                 if (graph_show_remainder(revs->graph))
134                                         putchar('\n');
135                         }
136                 } else {
137                         if (buf.len)
138                                 printf("%s%c", buf.buf, info->hdr_termination);
139                 }
140                 strbuf_release(&buf);
141         } else {
142                 if (graph_show_remainder(revs->graph))
143                         putchar('\n');
144         }
145         maybe_flush_or_die(stdout, "stdout");
146         finish_commit(commit, data);
147 }
148
149 static void finish_commit(struct commit *commit, void *data)
150 {
151         if (commit->parents) {
152                 free_commit_list(commit->parents);
153                 commit->parents = NULL;
154         }
155         free(commit->buffer);
156         commit->buffer = NULL;
157 }
158
159 static void finish_object(struct object *obj, const struct name_path *path, const char *name)
160 {
161         if (obj->type == OBJ_BLOB && !has_sha1_file(obj->sha1))
162                 die("missing blob object '%s'", sha1_to_hex(obj->sha1));
163 }
164
165 static void show_object(struct object *obj, const struct name_path *path, const char *component)
166 {
167         char *name = path_name(path, component);
168         /* An object with name "foo\n0000000..." can be used to
169          * confuse downstream "git pack-objects" very badly.
170          */
171         const char *ep = strchr(name, '\n');
172
173         finish_object(obj, path, name);
174         if (ep) {
175                 printf("%s %.*s\n", sha1_to_hex(obj->sha1),
176                        (int) (ep - name),
177                        name);
178         }
179         else
180                 printf("%s %s\n", sha1_to_hex(obj->sha1), name);
181         free(name);
182 }
183
184 static void show_edge(struct commit *commit)
185 {
186         printf("-%s\n", sha1_to_hex(commit->object.sha1));
187 }
188
189 static inline int log2i(int n)
190 {
191         int log2 = 0;
192
193         for (; n > 1; n >>= 1)
194                 log2++;
195
196         return log2;
197 }
198
199 static inline int exp2i(int n)
200 {
201         return 1 << n;
202 }
203
204 /*
205  * Estimate the number of bisect steps left (after the current step)
206  *
207  * For any x between 0 included and 2^n excluded, the probability for
208  * n - 1 steps left looks like:
209  *
210  * P(2^n + x) == (2^n - x) / (2^n + x)
211  *
212  * and P(2^n + x) < 0.5 means 2^n < 3x
213  */
214 int estimate_bisect_steps(int all)
215 {
216         int n, x, e;
217
218         if (all < 3)
219                 return 0;
220
221         n = log2i(all);
222         e = exp2i(n);
223         x = all - e;
224
225         return (e < 3 * x) ? n : n - 1;
226 }
227
228 void print_commit_list(struct commit_list *list,
229                        const char *format_cur,
230                        const char *format_last)
231 {
232         for ( ; list; list = list->next) {
233                 const char *format = list->next ? format_cur : format_last;
234                 printf(format, sha1_to_hex(list->item->object.sha1));
235         }
236 }
237
238 static void show_tried_revs(struct commit_list *tried)
239 {
240         printf("bisect_tried='");
241         print_commit_list(tried, "%s|", "%s");
242         printf("'\n");
243 }
244
245 static void print_var_str(const char *var, const char *val)
246 {
247         printf("%s='%s'\n", var, val);
248 }
249
250 static void print_var_int(const char *var, int val)
251 {
252         printf("%s=%d\n", var, val);
253 }
254
255 int show_bisect_vars(struct rev_list_info *info, int reaches, int all)
256 {
257         int cnt, flags = info->bisect_show_flags;
258         char hex[41] = "";
259         struct commit_list *tried;
260         struct rev_info *revs = info->revs;
261
262         if (!revs->commits && !(flags & BISECT_SHOW_TRIED))
263                 return 1;
264
265         revs->commits = filter_skipped(revs->commits, &tried,
266                                        flags & BISECT_SHOW_ALL,
267                                        NULL, NULL);
268
269         /*
270          * revs->commits can reach "reaches" commits among
271          * "all" commits.  If it is good, then there are
272          * (all-reaches) commits left to be bisected.
273          * On the other hand, if it is bad, then the set
274          * to bisect is "reaches".
275          * A bisect set of size N has (N-1) commits further
276          * to test, as we already know one bad one.
277          */
278         cnt = all - reaches;
279         if (cnt < reaches)
280                 cnt = reaches;
281
282         if (revs->commits)
283                 strcpy(hex, sha1_to_hex(revs->commits->item->object.sha1));
284
285         if (flags & BISECT_SHOW_ALL) {
286                 traverse_commit_list(revs, show_commit, show_object, info);
287                 printf("------\n");
288         }
289
290         if (flags & BISECT_SHOW_TRIED)
291                 show_tried_revs(tried);
292
293         print_var_str("bisect_rev", hex);
294         print_var_int("bisect_nr", cnt - 1);
295         print_var_int("bisect_good", all - reaches - 1);
296         print_var_int("bisect_bad", reaches - 1);
297         print_var_int("bisect_all", all);
298         print_var_int("bisect_steps", estimate_bisect_steps(all));
299
300         return 0;
301 }
302
303 int cmd_rev_list(int argc, const char **argv, const char *prefix)
304 {
305         struct rev_info revs;
306         struct rev_list_info info;
307         int i;
308         int read_from_stdin = 0;
309         int bisect_list = 0;
310         int bisect_show_vars = 0;
311         int bisect_find_all = 0;
312         int quiet = 0;
313
314         git_config(git_default_config, NULL);
315         init_revisions(&revs, prefix);
316         revs.abbrev = 0;
317         revs.commit_format = CMIT_FMT_UNSPECIFIED;
318         argc = setup_revisions(argc, argv, &revs, NULL);
319
320         memset(&info, 0, sizeof(info));
321         info.revs = &revs;
322
323         quiet = DIFF_OPT_TST(&revs.diffopt, QUIET);
324         for (i = 1 ; i < argc; i++) {
325                 const char *arg = argv[i];
326
327                 if (!strcmp(arg, "--header")) {
328                         revs.verbose_header = 1;
329                         continue;
330                 }
331                 if (!strcmp(arg, "--timestamp")) {
332                         info.show_timestamp = 1;
333                         continue;
334                 }
335                 if (!strcmp(arg, "--bisect")) {
336                         bisect_list = 1;
337                         continue;
338                 }
339                 if (!strcmp(arg, "--bisect-all")) {
340                         bisect_list = 1;
341                         bisect_find_all = 1;
342                         info.bisect_show_flags = BISECT_SHOW_ALL;
343                         revs.show_decorations = 1;
344                         continue;
345                 }
346                 if (!strcmp(arg, "--bisect-vars")) {
347                         bisect_list = 1;
348                         bisect_show_vars = 1;
349                         continue;
350                 }
351                 if (!strcmp(arg, "--stdin")) {
352                         if (read_from_stdin++)
353                                 die("--stdin given twice?");
354                         read_revisions_from_stdin(&revs);
355                         continue;
356                 }
357                 usage(rev_list_usage);
358
359         }
360         if (revs.commit_format != CMIT_FMT_UNSPECIFIED) {
361                 /* The command line has a --pretty  */
362                 info.hdr_termination = '\n';
363                 if (revs.commit_format == CMIT_FMT_ONELINE)
364                         info.header_prefix = "";
365                 else
366                         info.header_prefix = "commit ";
367         }
368         else if (revs.verbose_header)
369                 /* Only --header was specified */
370                 revs.commit_format = CMIT_FMT_RAW;
371
372         if ((!revs.commits &&
373              (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) &&
374               !revs.pending.nr)) ||
375             revs.diff)
376                 usage(rev_list_usage);
377
378         save_commit_buffer = revs.verbose_header ||
379                 revs.grep_filter.pattern_list;
380         if (bisect_list)
381                 revs.limited = 1;
382
383         if (prepare_revision_walk(&revs))
384                 die("revision walk setup failed");
385         if (revs.tree_objects)
386                 mark_edges_uninteresting(revs.commits, &revs, show_edge);
387
388         if (bisect_list) {
389                 int reaches = reaches, all = all;
390
391                 revs.commits = find_bisection(revs.commits, &reaches, &all,
392                                               bisect_find_all);
393
394                 if (bisect_show_vars)
395                         return show_bisect_vars(&info, reaches, all);
396         }
397
398         traverse_commit_list(&revs,
399                              quiet ? finish_commit : show_commit,
400                              quiet ? finish_object : show_object,
401                              &info);
402
403         return 0;
404 }