Merge branch 'cb/do-not-pretend-to-hijack-long-help'
[git] / builtin / fmt-merge-msg.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "commit.h"
4 #include "diff.h"
5 #include "revision.h"
6 #include "tag.h"
7 #include "string-list.h"
8
9 static const char * const fmt_merge_msg_usage[] = {
10         "git fmt-merge-msg [-m <message>] [--log[=<n>]|--no-log] [--file <file>]",
11         NULL
12 };
13
14 static int shortlog_len;
15
16 static int fmt_merge_msg_config(const char *key, const char *value, void *cb)
17 {
18         if (!strcmp(key, "merge.log") || !strcmp(key, "merge.summary")) {
19                 int is_bool;
20                 shortlog_len = git_config_bool_or_int(key, value, &is_bool);
21                 if (!is_bool && shortlog_len < 0)
22                         return error("%s: negative length %s", key, value);
23                 if (is_bool && shortlog_len)
24                         shortlog_len = DEFAULT_MERGE_LOG_LEN;
25         }
26         return 0;
27 }
28
29 struct src_data {
30         struct string_list branch, tag, r_branch, generic;
31         int head_status;
32 };
33
34 static void init_src_data(struct src_data *data)
35 {
36         data->branch.strdup_strings = 1;
37         data->tag.strdup_strings = 1;
38         data->r_branch.strdup_strings = 1;
39         data->generic.strdup_strings = 1;
40 }
41
42 static struct string_list srcs = STRING_LIST_INIT_DUP;
43 static struct string_list origins = STRING_LIST_INIT_DUP;
44
45 static int handle_line(char *line)
46 {
47         int i, len = strlen(line);
48         unsigned char *sha1;
49         char *src, *origin;
50         struct src_data *src_data;
51         struct string_list_item *item;
52         int pulling_head = 0;
53
54         if (len < 43 || line[40] != '\t')
55                 return 1;
56
57         if (!prefixcmp(line + 41, "not-for-merge"))
58                 return 0;
59
60         if (line[41] != '\t')
61                 return 2;
62
63         line[40] = 0;
64         sha1 = xmalloc(20);
65         i = get_sha1(line, sha1);
66         line[40] = '\t';
67         if (i)
68                 return 3;
69
70         if (line[len - 1] == '\n')
71                 line[len - 1] = 0;
72         line += 42;
73
74         src = strstr(line, " of ");
75         if (src) {
76                 *src = 0;
77                 src += 4;
78                 pulling_head = 0;
79         } else {
80                 src = line;
81                 pulling_head = 1;
82         }
83
84         item = unsorted_string_list_lookup(&srcs, src);
85         if (!item) {
86                 item = string_list_append(&srcs, src);
87                 item->util = xcalloc(1, sizeof(struct src_data));
88                 init_src_data(item->util);
89         }
90         src_data = item->util;
91
92         if (pulling_head) {
93                 origin = src;
94                 src_data->head_status |= 1;
95         } else if (!prefixcmp(line, "branch ")) {
96                 origin = line + 7;
97                 string_list_append(&src_data->branch, origin);
98                 src_data->head_status |= 2;
99         } else if (!prefixcmp(line, "tag ")) {
100                 origin = line;
101                 string_list_append(&src_data->tag, origin + 4);
102                 src_data->head_status |= 2;
103         } else if (!prefixcmp(line, "remote-tracking branch ")) {
104                 origin = line + strlen("remote-tracking branch ");
105                 string_list_append(&src_data->r_branch, origin);
106                 src_data->head_status |= 2;
107         } else {
108                 origin = src;
109                 string_list_append(&src_data->generic, line);
110                 src_data->head_status |= 2;
111         }
112
113         if (!strcmp(".", src) || !strcmp(src, origin)) {
114                 int len = strlen(origin);
115                 if (origin[0] == '\'' && origin[len - 1] == '\'')
116                         origin = xmemdupz(origin + 1, len - 2);
117         } else {
118                 char *new_origin = xmalloc(strlen(origin) + strlen(src) + 5);
119                 sprintf(new_origin, "%s of %s", origin, src);
120                 origin = new_origin;
121         }
122         string_list_append(&origins, origin)->util = sha1;
123         return 0;
124 }
125
126 static void print_joined(const char *singular, const char *plural,
127                 struct string_list *list, struct strbuf *out)
128 {
129         if (list->nr == 0)
130                 return;
131         if (list->nr == 1) {
132                 strbuf_addf(out, "%s%s", singular, list->items[0].string);
133         } else {
134                 int i;
135                 strbuf_addstr(out, plural);
136                 for (i = 0; i < list->nr - 1; i++)
137                         strbuf_addf(out, "%s%s", i > 0 ? ", " : "",
138                                     list->items[i].string);
139                 strbuf_addf(out, " and %s", list->items[list->nr - 1].string);
140         }
141 }
142
143 static void shortlog(const char *name, unsigned char *sha1,
144                 struct commit *head, struct rev_info *rev, int limit,
145                 struct strbuf *out)
146 {
147         int i, count = 0;
148         struct commit *commit;
149         struct object *branch;
150         struct string_list subjects = STRING_LIST_INIT_DUP;
151         int flags = UNINTERESTING | TREESAME | SEEN | SHOWN | ADDED;
152         struct strbuf sb = STRBUF_INIT;
153
154         branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
155         if (!branch || branch->type != OBJ_COMMIT)
156                 return;
157
158         setup_revisions(0, NULL, rev, NULL);
159         rev->ignore_merges = 1;
160         add_pending_object(rev, branch, name);
161         add_pending_object(rev, &head->object, "^HEAD");
162         head->object.flags |= UNINTERESTING;
163         if (prepare_revision_walk(rev))
164                 die("revision walk setup failed");
165         while ((commit = get_revision(rev)) != NULL) {
166                 struct pretty_print_context ctx = {0};
167
168                 /* ignore merges */
169                 if (commit->parents && commit->parents->next)
170                         continue;
171
172                 count++;
173                 if (subjects.nr > limit)
174                         continue;
175
176                 format_commit_message(commit, "%s", &sb, &ctx);
177                 strbuf_ltrim(&sb);
178
179                 if (!sb.len)
180                         string_list_append(&subjects,
181                                            sha1_to_hex(commit->object.sha1));
182                 else
183                         string_list_append(&subjects, strbuf_detach(&sb, NULL));
184         }
185
186         if (count > limit)
187                 strbuf_addf(out, "\n* %s: (%d commits)\n", name, count);
188         else
189                 strbuf_addf(out, "\n* %s:\n", name);
190
191         for (i = 0; i < subjects.nr; i++)
192                 if (i >= limit)
193                         strbuf_addf(out, "  ...\n");
194                 else
195                         strbuf_addf(out, "  %s\n", subjects.items[i].string);
196
197         clear_commit_marks((struct commit *)branch, flags);
198         clear_commit_marks(head, flags);
199         free_commit_list(rev->commits);
200         rev->commits = NULL;
201         rev->pending.nr = 0;
202
203         string_list_clear(&subjects, 0);
204 }
205
206 static void do_fmt_merge_msg_title(struct strbuf *out,
207         const char *current_branch) {
208         int i = 0;
209         char *sep = "";
210
211         strbuf_addstr(out, "Merge ");
212         for (i = 0; i < srcs.nr; i++) {
213                 struct src_data *src_data = srcs.items[i].util;
214                 const char *subsep = "";
215
216                 strbuf_addstr(out, sep);
217                 sep = "; ";
218
219                 if (src_data->head_status == 1) {
220                         strbuf_addstr(out, srcs.items[i].string);
221                         continue;
222                 }
223                 if (src_data->head_status == 3) {
224                         subsep = ", ";
225                         strbuf_addstr(out, "HEAD");
226                 }
227                 if (src_data->branch.nr) {
228                         strbuf_addstr(out, subsep);
229                         subsep = ", ";
230                         print_joined("branch ", "branches ", &src_data->branch,
231                                         out);
232                 }
233                 if (src_data->r_branch.nr) {
234                         strbuf_addstr(out, subsep);
235                         subsep = ", ";
236                         print_joined("remote-tracking branch ", "remote-tracking branches ",
237                                         &src_data->r_branch, out);
238                 }
239                 if (src_data->tag.nr) {
240                         strbuf_addstr(out, subsep);
241                         subsep = ", ";
242                         print_joined("tag ", "tags ", &src_data->tag, out);
243                 }
244                 if (src_data->generic.nr) {
245                         strbuf_addstr(out, subsep);
246                         print_joined("commit ", "commits ", &src_data->generic,
247                                         out);
248                 }
249                 if (strcmp(".", srcs.items[i].string))
250                         strbuf_addf(out, " of %s", srcs.items[i].string);
251         }
252
253         if (!strcmp("master", current_branch))
254                 strbuf_addch(out, '\n');
255         else
256                 strbuf_addf(out, " into %s\n", current_branch);
257 }
258
259 static int do_fmt_merge_msg(int merge_title, struct strbuf *in,
260         struct strbuf *out, int shortlog_len) {
261         int i = 0, pos = 0;
262         unsigned char head_sha1[20];
263         const char *current_branch;
264
265         /* get current branch */
266         current_branch = resolve_ref("HEAD", head_sha1, 1, NULL);
267         if (!current_branch)
268                 die("No current branch");
269         if (!prefixcmp(current_branch, "refs/heads/"))
270                 current_branch += 11;
271
272         /* get a line */
273         while (pos < in->len) {
274                 int len;
275                 char *newline, *p = in->buf + pos;
276
277                 newline = strchr(p, '\n');
278                 len = newline ? newline - p : strlen(p);
279                 pos += len + !!newline;
280                 i++;
281                 p[len] = 0;
282                 if (handle_line(p))
283                         die ("Error in line %d: %.*s", i, len, p);
284         }
285
286         if (!srcs.nr)
287                 return 0;
288
289         if (merge_title)
290                 do_fmt_merge_msg_title(out, current_branch);
291
292         if (shortlog_len) {
293                 struct commit *head;
294                 struct rev_info rev;
295
296                 head = lookup_commit(head_sha1);
297                 init_revisions(&rev, NULL);
298                 rev.commit_format = CMIT_FMT_ONELINE;
299                 rev.ignore_merges = 1;
300                 rev.limited = 1;
301
302                 if (suffixcmp(out->buf, "\n"))
303                         strbuf_addch(out, '\n');
304
305                 for (i = 0; i < origins.nr; i++)
306                         shortlog(origins.items[i].string, origins.items[i].util,
307                                         head, &rev, shortlog_len, out);
308         }
309         return 0;
310 }
311
312 int fmt_merge_msg(struct strbuf *in, struct strbuf *out,
313                   int merge_title, int shortlog_len) {
314         return do_fmt_merge_msg(merge_title, in, out, shortlog_len);
315 }
316
317 int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
318 {
319         const char *inpath = NULL;
320         const char *message = NULL;
321         struct option options[] = {
322                 { OPTION_INTEGER, 0, "log", &shortlog_len, "n",
323                   "populate log with at most <n> entries from shortlog",
324                   PARSE_OPT_OPTARG, NULL, DEFAULT_MERGE_LOG_LEN },
325                 { OPTION_INTEGER, 0, "summary", &shortlog_len, "n",
326                   "alias for --log (deprecated)",
327                   PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, NULL,
328                   DEFAULT_MERGE_LOG_LEN },
329                 OPT_STRING('m', "message", &message, "text",
330                         "use <text> as start of message"),
331                 OPT_FILENAME('F', "file", &inpath, "file to read from"),
332                 OPT_END()
333         };
334
335         FILE *in = stdin;
336         struct strbuf input = STRBUF_INIT, output = STRBUF_INIT;
337         int ret;
338
339         git_config(fmt_merge_msg_config, NULL);
340         argc = parse_options(argc, argv, prefix, options, fmt_merge_msg_usage,
341                              0);
342         if (argc > 0)
343                 usage_with_options(fmt_merge_msg_usage, options);
344         if (message && !shortlog_len) {
345                 char nl = '\n';
346                 write_in_full(STDOUT_FILENO, message, strlen(message));
347                 write_in_full(STDOUT_FILENO, &nl, 1);
348                 return 0;
349         }
350         if (shortlog_len < 0)
351                 die("Negative --log=%d", shortlog_len);
352
353         if (inpath && strcmp(inpath, "-")) {
354                 in = fopen(inpath, "r");
355                 if (!in)
356                         die_errno("cannot open '%s'", inpath);
357         }
358
359         if (strbuf_read(&input, fileno(in), 0) < 0)
360                 die_errno("could not read input file");
361
362         if (message)
363                 strbuf_addstr(&output, message);
364         ret = fmt_merge_msg(&input, &output,
365                             message ? 0 : 1,
366                             shortlog_len);
367
368         if (ret)
369                 return ret;
370         write_in_full(STDOUT_FILENO, output.buf, output.len);
371         return 0;
372 }