user-manual: add "quick start" as chapter 1
[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
8 static const char *fmt_merge_msg_usage =
9         "git-fmt-merge-msg [--summary] [--no-summary] [--file <file>]";
10
11 static int merge_summary;
12
13 static int fmt_merge_msg_config(const char *key, const char *value)
14 {
15         if (!strcmp("merge.summary", key))
16                 merge_summary = git_config_bool(key, value);
17         return 0;
18 }
19
20 struct list {
21         char **list;
22         void **payload;
23         unsigned nr, alloc;
24 };
25
26 static void append_to_list(struct list *list, char *value, void *payload)
27 {
28         if (list->nr == list->alloc) {
29                 list->alloc += 32;
30                 list->list = xrealloc(list->list, sizeof(char *) * list->alloc);
31                 list->payload = xrealloc(list->payload,
32                                 sizeof(char *) * list->alloc);
33         }
34         list->payload[list->nr] = payload;
35         list->list[list->nr++] = value;
36 }
37
38 static int find_in_list(struct list *list, char *value)
39 {
40         int i;
41
42         for (i = 0; i < list->nr; i++)
43                 if (!strcmp(list->list[i], value))
44                         return i;
45
46         return -1;
47 }
48
49 static void free_list(struct list *list)
50 {
51         int i;
52
53         if (list->alloc == 0)
54                 return;
55
56         for (i = 0; i < list->nr; i++) {
57                 free(list->list[i]);
58                 free(list->payload[i]);
59         }
60         free(list->list);
61         free(list->payload);
62         list->nr = list->alloc = 0;
63 }
64
65 struct src_data {
66         struct list branch, tag, r_branch, generic;
67         int head_status;
68 };
69
70 static struct list srcs = { NULL, NULL, 0, 0};
71 static struct list origins = { NULL, NULL, 0, 0};
72
73 static int handle_line(char *line)
74 {
75         int i, len = strlen(line);
76         unsigned char *sha1;
77         char *src, *origin;
78         struct src_data *src_data;
79         int pulling_head = 0;
80
81         if (len < 43 || line[40] != '\t')
82                 return 1;
83
84         if (!strncmp(line + 41, "not-for-merge", 13))
85                 return 0;
86
87         if (line[41] != '\t')
88                 return 2;
89
90         line[40] = 0;
91         sha1 = xmalloc(20);
92         i = get_sha1(line, sha1);
93         line[40] = '\t';
94         if (i)
95                 return 3;
96
97         if (line[len - 1] == '\n')
98                 line[len - 1] = 0;
99         line += 42;
100
101         src = strstr(line, " of ");
102         if (src) {
103                 *src = 0;
104                 src += 4;
105                 pulling_head = 0;
106         } else {
107                 src = line;
108                 pulling_head = 1;
109         }
110
111         i = find_in_list(&srcs, src);
112         if (i < 0) {
113                 i = srcs.nr;
114                 append_to_list(&srcs, xstrdup(src),
115                                 xcalloc(1, sizeof(struct src_data)));
116         }
117         src_data = srcs.payload[i];
118
119         if (pulling_head) {
120                 origin = xstrdup(src);
121                 src_data->head_status |= 1;
122         } else if (!strncmp(line, "branch ", 7)) {
123                 origin = xstrdup(line + 7);
124                 append_to_list(&src_data->branch, origin, NULL);
125                 src_data->head_status |= 2;
126         } else if (!strncmp(line, "tag ", 4)) {
127                 origin = line;
128                 append_to_list(&src_data->tag, xstrdup(origin + 4), NULL);
129                 src_data->head_status |= 2;
130         } else if (!strncmp(line, "remote branch ", 14)) {
131                 origin = xstrdup(line + 14);
132                 append_to_list(&src_data->r_branch, origin, NULL);
133                 src_data->head_status |= 2;
134         } else {
135                 origin = xstrdup(src);
136                 append_to_list(&src_data->generic, xstrdup(line), NULL);
137                 src_data->head_status |= 2;
138         }
139
140         if (!strcmp(".", src) || !strcmp(src, origin)) {
141                 int len = strlen(origin);
142                 if (origin[0] == '\'' && origin[len - 1] == '\'') {
143                         char *new_origin = xmalloc(len - 1);
144                         memcpy(new_origin, origin + 1, len - 2);
145                         new_origin[len - 2] = 0;
146                         origin = new_origin;
147                 } else
148                         origin = xstrdup(origin);
149         } else {
150                 char *new_origin = xmalloc(strlen(origin) + strlen(src) + 5);
151                 sprintf(new_origin, "%s of %s", origin, src);
152                 origin = new_origin;
153         }
154         append_to_list(&origins, origin, sha1);
155         return 0;
156 }
157
158 static void print_joined(const char *singular, const char *plural,
159                 struct list *list)
160 {
161         if (list->nr == 0)
162                 return;
163         if (list->nr == 1) {
164                 printf("%s%s", singular, list->list[0]);
165         } else {
166                 int i;
167                 printf("%s", plural);
168                 for (i = 0; i < list->nr - 1; i++)
169                         printf("%s%s", i > 0 ? ", " : "", list->list[i]);
170                 printf(" and %s", list->list[list->nr - 1]);
171         }
172 }
173
174 static void shortlog(const char *name, unsigned char *sha1,
175                 struct commit *head, struct rev_info *rev, int limit)
176 {
177         int i, count = 0;
178         struct commit *commit;
179         struct object *branch;
180         struct list subjects = { NULL, NULL, 0, 0 };
181         int flags = UNINTERESTING | TREECHANGE | SEEN | SHOWN | ADDED;
182
183         branch = deref_tag(parse_object(sha1), sha1_to_hex(sha1), 40);
184         if (!branch || branch->type != OBJ_COMMIT)
185                 return;
186
187         setup_revisions(0, NULL, rev, NULL);
188         rev->ignore_merges = 1;
189         add_pending_object(rev, branch, name);
190         add_pending_object(rev, &head->object, "^HEAD");
191         head->object.flags |= UNINTERESTING;
192         prepare_revision_walk(rev);
193         while ((commit = get_revision(rev)) != NULL) {
194                 char *oneline, *bol, *eol;
195
196                 /* ignore merges */
197                 if (commit->parents && commit->parents->next)
198                         continue;
199
200                 count++;
201                 if (subjects.nr > limit)
202                         continue;
203
204                 bol = strstr(commit->buffer, "\n\n");
205                 if (!bol) {
206                         append_to_list(&subjects, xstrdup(sha1_to_hex(
207                                                         commit->object.sha1)),
208                                         NULL);
209                         continue;
210                 }
211
212                 bol += 2;
213                 eol = strchr(bol, '\n');
214
215                 if (eol) {
216                         int len = eol - bol;
217                         oneline = xmalloc(len + 1);
218                         memcpy(oneline, bol, len);
219                         oneline[len] = 0;
220                 } else
221                         oneline = xstrdup(bol);
222                 append_to_list(&subjects, oneline, NULL);
223         }
224
225         if (count > limit)
226                 printf("\n* %s: (%d commits)\n", name, count);
227         else
228                 printf("\n* %s:\n", name);
229
230         for (i = 0; i < subjects.nr; i++)
231                 if (i >= limit)
232                         printf("  ...\n");
233                 else
234                         printf("  %s\n", subjects.list[i]);
235
236         clear_commit_marks((struct commit *)branch, flags);
237         clear_commit_marks(head, flags);
238         free_commit_list(rev->commits);
239         rev->commits = NULL;
240         rev->pending.nr = 0;
241
242         free_list(&subjects);
243 }
244
245 int cmd_fmt_merge_msg(int argc, const char **argv, const char *prefix)
246 {
247         int limit = 20, i = 0;
248         char line[1024];
249         FILE *in = stdin;
250         const char *sep = "";
251         unsigned char head_sha1[20];
252         const char *current_branch;
253
254         git_config(fmt_merge_msg_config);
255
256         while (argc > 1) {
257                 if (!strcmp(argv[1], "--summary"))
258                         merge_summary = 1;
259                 else if (!strcmp(argv[1], "--no-summary"))
260                         merge_summary = 0;
261                 else if (!strcmp(argv[1], "-F") || !strcmp(argv[1], "--file")) {
262                         if (argc < 2)
263                                 die ("Which file?");
264                         if (!strcmp(argv[2], "-"))
265                                 in = stdin;
266                         else {
267                                 fclose(in);
268                                 in = fopen(argv[2], "r");
269                         }
270                         argc--; argv++;
271                 } else
272                         break;
273                 argc--; argv++;
274         }
275
276         if (argc > 1)
277                 usage(fmt_merge_msg_usage);
278
279         /* get current branch */
280         current_branch = resolve_ref("HEAD", head_sha1, 1, NULL);
281         if (!current_branch)
282                 die("No current branch");
283         if (!strncmp(current_branch, "refs/heads/", 11))
284                 current_branch += 11;
285
286         while (fgets(line, sizeof(line), in)) {
287                 i++;
288                 if (line[0] == 0)
289                         continue;
290                 if (handle_line(line))
291                         die ("Error in line %d: %s", i, line);
292         }
293
294         printf("Merge ");
295         for (i = 0; i < srcs.nr; i++) {
296                 struct src_data *src_data = srcs.payload[i];
297                 const char *subsep = "";
298
299                 printf(sep);
300                 sep = "; ";
301
302                 if (src_data->head_status == 1) {
303                         printf(srcs.list[i]);
304                         continue;
305                 }
306                 if (src_data->head_status == 3) {
307                         subsep = ", ";
308                         printf("HEAD");
309                 }
310                 if (src_data->branch.nr) {
311                         printf(subsep);
312                         subsep = ", ";
313                         print_joined("branch ", "branches ", &src_data->branch);
314                 }
315                 if (src_data->r_branch.nr) {
316                         printf(subsep);
317                         subsep = ", ";
318                         print_joined("remote branch ", "remote branches ",
319                                         &src_data->r_branch);
320                 }
321                 if (src_data->tag.nr) {
322                         printf(subsep);
323                         subsep = ", ";
324                         print_joined("tag ", "tags ", &src_data->tag);
325                 }
326                 if (src_data->generic.nr) {
327                         printf(subsep);
328                         print_joined("commit ", "commits ", &src_data->generic);
329                 }
330                 if (strcmp(".", srcs.list[i]))
331                         printf(" of %s", srcs.list[i]);
332         }
333
334         if (!strcmp("master", current_branch))
335                 putchar('\n');
336         else
337                 printf(" into %s\n", current_branch);
338
339         if (merge_summary) {
340                 struct commit *head;
341                 struct rev_info rev;
342
343                 head = lookup_commit(head_sha1);
344                 init_revisions(&rev, prefix);
345                 rev.commit_format = CMIT_FMT_ONELINE;
346                 rev.ignore_merges = 1;
347                 rev.limited = 1;
348
349                 for (i = 0; i < origins.nr; i++)
350                         shortlog(origins.list[i], origins.payload[i],
351                                         head, &rev, limit);
352         }
353
354         /* No cleanup yet; is standalone anyway */
355
356         return 0;
357 }
358