rev-list: check reflog_info before showing usage
[git] / reflog-walk.c
1 #include "cache.h"
2 #include "commit.h"
3 #include "refs.h"
4 #include "diff.h"
5 #include "revision.h"
6 #include "string-list.h"
7 #include "reflog-walk.h"
8
9 struct complete_reflogs {
10         char *ref;
11         const char *short_ref;
12         struct reflog_info {
13                 struct object_id ooid, noid;
14                 char *email;
15                 timestamp_t timestamp;
16                 int tz;
17                 char *message;
18         } *items;
19         int nr, alloc;
20 };
21
22 static int read_one_reflog(struct object_id *ooid, struct object_id *noid,
23                 const char *email, timestamp_t timestamp, int tz,
24                 const char *message, void *cb_data)
25 {
26         struct complete_reflogs *array = cb_data;
27         struct reflog_info *item;
28
29         ALLOC_GROW(array->items, array->nr + 1, array->alloc);
30         item = array->items + array->nr;
31         oidcpy(&item->ooid, ooid);
32         oidcpy(&item->noid, noid);
33         item->email = xstrdup(email);
34         item->timestamp = timestamp;
35         item->tz = tz;
36         item->message = xstrdup(message);
37         array->nr++;
38         return 0;
39 }
40
41 static void free_complete_reflog(struct complete_reflogs *array)
42 {
43         int i;
44
45         if (!array)
46                 return;
47
48         for (i = 0; i < array->nr; i++) {
49                 free(array->items[i].email);
50                 free(array->items[i].message);
51         }
52         free(array->items);
53         free(array->ref);
54         free(array);
55 }
56
57 static struct complete_reflogs *read_complete_reflog(const char *ref)
58 {
59         struct complete_reflogs *reflogs =
60                 xcalloc(1, sizeof(struct complete_reflogs));
61         reflogs->ref = xstrdup(ref);
62         for_each_reflog_ent(ref, read_one_reflog, reflogs);
63         if (reflogs->nr == 0) {
64                 struct object_id oid;
65                 const char *name;
66                 void *name_to_free;
67                 name = name_to_free = resolve_refdup(ref, RESOLVE_REF_READING,
68                                                      oid.hash, NULL);
69                 if (name) {
70                         for_each_reflog_ent(name, read_one_reflog, reflogs);
71                         free(name_to_free);
72                 }
73         }
74         if (reflogs->nr == 0) {
75                 char *refname = xstrfmt("refs/%s", ref);
76                 for_each_reflog_ent(refname, read_one_reflog, reflogs);
77                 if (reflogs->nr == 0) {
78                         free(refname);
79                         refname = xstrfmt("refs/heads/%s", ref);
80                         for_each_reflog_ent(refname, read_one_reflog, reflogs);
81                 }
82                 free(refname);
83         }
84         return reflogs;
85 }
86
87 static int get_reflog_recno_by_time(struct complete_reflogs *array,
88         timestamp_t timestamp)
89 {
90         int i;
91         for (i = array->nr - 1; i >= 0; i--)
92                 if (timestamp >= array->items[i].timestamp)
93                         return i;
94         return -1;
95 }
96
97 struct commit_info_lifo {
98         struct commit_info {
99                 struct commit *commit;
100                 void *util;
101         } *items;
102         int nr, alloc;
103 };
104
105 static struct commit_info *get_commit_info(struct commit *commit,
106                 struct commit_info_lifo *lifo, int pop)
107 {
108         int i;
109         for (i = 0; i < lifo->nr; i++)
110                 if (lifo->items[i].commit == commit) {
111                         struct commit_info *result = &lifo->items[i];
112                         if (pop) {
113                                 if (i + 1 < lifo->nr)
114                                         memmove(lifo->items + i,
115                                                 lifo->items + i + 1,
116                                                 (lifo->nr - i) *
117                                                 sizeof(struct commit_info));
118                                 lifo->nr--;
119                         }
120                         return result;
121                 }
122         return NULL;
123 }
124
125 static void add_commit_info(struct commit *commit, void *util,
126                 struct commit_info_lifo *lifo)
127 {
128         struct commit_info *info;
129         ALLOC_GROW(lifo->items, lifo->nr + 1, lifo->alloc);
130         info = lifo->items + lifo->nr;
131         info->commit = commit;
132         info->util = util;
133         lifo->nr++;
134 }
135
136 struct commit_reflog {
137         int recno;
138         enum selector_type {
139                 SELECTOR_NONE,
140                 SELECTOR_INDEX,
141                 SELECTOR_DATE
142         } selector;
143         struct complete_reflogs *reflogs;
144 };
145
146 struct reflog_walk_info {
147         struct commit_info_lifo reflogs;
148         struct string_list complete_reflogs;
149         struct commit_reflog *last_commit_reflog;
150 };
151
152 void init_reflog_walk(struct reflog_walk_info **info)
153 {
154         *info = xcalloc(1, sizeof(struct reflog_walk_info));
155         (*info)->complete_reflogs.strdup_strings = 1;
156 }
157
158 int add_reflog_for_walk(struct reflog_walk_info *info,
159                 struct commit *commit, const char *name)
160 {
161         timestamp_t timestamp = 0;
162         int recno = -1;
163         struct string_list_item *item;
164         struct complete_reflogs *reflogs;
165         char *branch, *at = strchr(name, '@');
166         struct commit_reflog *commit_reflog;
167         enum selector_type selector = SELECTOR_NONE;
168
169         if (commit->object.flags & UNINTERESTING)
170                 die ("Cannot walk reflogs for %s", name);
171
172         branch = xstrdup(name);
173         if (at && at[1] == '{') {
174                 char *ep;
175                 branch[at - name] = '\0';
176                 recno = strtoul(at + 2, &ep, 10);
177                 if (*ep != '}') {
178                         recno = -1;
179                         timestamp = approxidate(at + 2);
180                         selector = SELECTOR_DATE;
181                 }
182                 else
183                         selector = SELECTOR_INDEX;
184         } else
185                 recno = 0;
186
187         item = string_list_lookup(&info->complete_reflogs, branch);
188         if (item)
189                 reflogs = item->util;
190         else {
191                 if (*branch == '\0') {
192                         struct object_id oid;
193                         free(branch);
194                         branch = resolve_refdup("HEAD", 0, oid.hash, NULL);
195                         if (!branch)
196                                 die ("No current branch");
197
198                 }
199                 reflogs = read_complete_reflog(branch);
200                 if (!reflogs || reflogs->nr == 0) {
201                         struct object_id oid;
202                         char *b;
203                         int ret = dwim_log(branch, strlen(branch),
204                                            oid.hash, &b);
205                         if (ret > 1)
206                                 free(b);
207                         else if (ret == 1) {
208                                 free_complete_reflog(reflogs);
209                                 free(branch);
210                                 branch = b;
211                                 reflogs = read_complete_reflog(branch);
212                         }
213                 }
214                 if (!reflogs || reflogs->nr == 0) {
215                         free_complete_reflog(reflogs);
216                         free(branch);
217                         return -1;
218                 }
219                 string_list_insert(&info->complete_reflogs, branch)->util
220                         = reflogs;
221         }
222         free(branch);
223
224         commit_reflog = xcalloc(1, sizeof(struct commit_reflog));
225         if (recno < 0) {
226                 commit_reflog->recno = get_reflog_recno_by_time(reflogs, timestamp);
227                 if (commit_reflog->recno < 0) {
228                         free(commit_reflog);
229                         return -1;
230                 }
231         } else
232                 commit_reflog->recno = reflogs->nr - recno - 1;
233         commit_reflog->selector = selector;
234         commit_reflog->reflogs = reflogs;
235
236         add_commit_info(commit, commit_reflog, &info->reflogs);
237         return 0;
238 }
239
240 void fake_reflog_parent(struct reflog_walk_info *info, struct commit *commit)
241 {
242         struct commit_info *commit_info =
243                 get_commit_info(commit, &info->reflogs, 0);
244         struct commit_reflog *commit_reflog;
245         struct object *logobj;
246         struct reflog_info *reflog;
247
248         info->last_commit_reflog = NULL;
249         if (!commit_info)
250                 return;
251
252         commit_reflog = commit_info->util;
253         if (commit_reflog->recno < 0) {
254                 commit->parents = NULL;
255                 return;
256         }
257         info->last_commit_reflog = commit_reflog;
258
259         do {
260                 reflog = &commit_reflog->reflogs->items[commit_reflog->recno];
261                 commit_reflog->recno--;
262                 logobj = parse_object(&reflog->ooid);
263         } while (commit_reflog->recno && (logobj && logobj->type != OBJ_COMMIT));
264
265         if (!logobj && commit_reflog->recno >= 0 && is_null_oid(&reflog->ooid)) {
266                 /* a root commit, but there are still more entries to show */
267                 reflog = &commit_reflog->reflogs->items[commit_reflog->recno];
268                 logobj = parse_object(&reflog->noid);
269                 if (!logobj)
270                         logobj = parse_object(&reflog->ooid);
271         }
272
273         if (!logobj || logobj->type != OBJ_COMMIT) {
274                 commit_info->commit = NULL;
275                 commit->parents = NULL;
276                 return;
277         }
278         commit_info->commit = (struct commit *)logobj;
279
280         commit->parents = xcalloc(1, sizeof(struct commit_list));
281         commit->parents->item = commit_info->commit;
282 }
283
284 void get_reflog_selector(struct strbuf *sb,
285                          struct reflog_walk_info *reflog_info,
286                          const struct date_mode *dmode, int force_date,
287                          int shorten)
288 {
289         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
290         struct reflog_info *info;
291         const char *printed_ref;
292
293         if (!commit_reflog)
294                 return;
295
296         if (shorten) {
297                 if (!commit_reflog->reflogs->short_ref)
298                         commit_reflog->reflogs->short_ref
299                                 = shorten_unambiguous_ref(commit_reflog->reflogs->ref, 0);
300                 printed_ref = commit_reflog->reflogs->short_ref;
301         } else {
302                 printed_ref = commit_reflog->reflogs->ref;
303         }
304
305         strbuf_addf(sb, "%s@{", printed_ref);
306         if (commit_reflog->selector == SELECTOR_DATE ||
307             (commit_reflog->selector == SELECTOR_NONE && force_date)) {
308                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
309                 strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));
310         } else {
311                 strbuf_addf(sb, "%d", commit_reflog->reflogs->nr
312                             - 2 - commit_reflog->recno);
313         }
314
315         strbuf_addch(sb, '}');
316 }
317
318 void get_reflog_message(struct strbuf *sb,
319                         struct reflog_walk_info *reflog_info)
320 {
321         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
322         struct reflog_info *info;
323         size_t len;
324
325         if (!commit_reflog)
326                 return;
327
328         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
329         len = strlen(info->message);
330         if (len > 0)
331                 len--; /* strip away trailing newline */
332         strbuf_add(sb, info->message, len);
333 }
334
335 const char *get_reflog_ident(struct reflog_walk_info *reflog_info)
336 {
337         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
338         struct reflog_info *info;
339
340         if (!commit_reflog)
341                 return NULL;
342
343         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
344         return info->email;
345 }
346
347 void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,
348                          const struct date_mode *dmode, int force_date)
349 {
350         if (reflog_info && reflog_info->last_commit_reflog) {
351                 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
352                 struct reflog_info *info;
353                 struct strbuf selector = STRBUF_INIT;
354
355                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
356                 get_reflog_selector(&selector, reflog_info, dmode, force_date, 0);
357                 if (oneline) {
358                         printf("%s: %s", selector.buf, info->message);
359                 }
360                 else {
361                         printf("Reflog: %s (%s)\nReflog message: %s",
362                                selector.buf, info->email, info->message);
363                 }
364
365                 strbuf_release(&selector);
366         }
367 }
368
369 int reflog_walk_empty(struct reflog_walk_info *info)
370 {
371         return !info || !info->reflogs.nr;
372 }