hex: add functions to parse hex object IDs in any algorithm
[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                 const char *name;
65                 void *name_to_free;
66                 name = name_to_free = resolve_refdup(ref, RESOLVE_REF_READING,
67                                                      NULL, NULL);
68                 if (name) {
69                         for_each_reflog_ent(name, read_one_reflog, reflogs);
70                         free(name_to_free);
71                 }
72         }
73         if (reflogs->nr == 0) {
74                 char *refname = xstrfmt("refs/%s", ref);
75                 for_each_reflog_ent(refname, read_one_reflog, reflogs);
76                 if (reflogs->nr == 0) {
77                         free(refname);
78                         refname = xstrfmt("refs/heads/%s", ref);
79                         for_each_reflog_ent(refname, read_one_reflog, reflogs);
80                 }
81                 free(refname);
82         }
83         return reflogs;
84 }
85
86 static int get_reflog_recno_by_time(struct complete_reflogs *array,
87         timestamp_t timestamp)
88 {
89         int i;
90         for (i = array->nr - 1; i >= 0; i--)
91                 if (timestamp >= array->items[i].timestamp)
92                         return i;
93         return -1;
94 }
95
96 struct commit_reflog {
97         int recno;
98         enum selector_type {
99                 SELECTOR_NONE,
100                 SELECTOR_INDEX,
101                 SELECTOR_DATE
102         } selector;
103         struct complete_reflogs *reflogs;
104 };
105
106 struct reflog_walk_info {
107         struct commit_reflog **logs;
108         size_t nr, alloc;
109         struct string_list complete_reflogs;
110         struct commit_reflog *last_commit_reflog;
111 };
112
113 void init_reflog_walk(struct reflog_walk_info **info)
114 {
115         *info = xcalloc(1, sizeof(struct reflog_walk_info));
116         (*info)->complete_reflogs.strdup_strings = 1;
117 }
118
119 int add_reflog_for_walk(struct reflog_walk_info *info,
120                 struct commit *commit, const char *name)
121 {
122         timestamp_t timestamp = 0;
123         int recno = -1;
124         struct string_list_item *item;
125         struct complete_reflogs *reflogs;
126         char *branch, *at = strchr(name, '@');
127         struct commit_reflog *commit_reflog;
128         enum selector_type selector = SELECTOR_NONE;
129
130         if (commit->object.flags & UNINTERESTING)
131                 die("cannot walk reflogs for %s", name);
132
133         branch = xstrdup(name);
134         if (at && at[1] == '{') {
135                 char *ep;
136                 branch[at - name] = '\0';
137                 recno = strtoul(at + 2, &ep, 10);
138                 if (*ep != '}') {
139                         recno = -1;
140                         timestamp = approxidate(at + 2);
141                         selector = SELECTOR_DATE;
142                 }
143                 else
144                         selector = SELECTOR_INDEX;
145         } else
146                 recno = 0;
147
148         item = string_list_lookup(&info->complete_reflogs, branch);
149         if (item)
150                 reflogs = item->util;
151         else {
152                 if (*branch == '\0') {
153                         free(branch);
154                         branch = resolve_refdup("HEAD", 0, NULL, NULL);
155                         if (!branch)
156                                 die("no current branch");
157
158                 }
159                 reflogs = read_complete_reflog(branch);
160                 if (!reflogs || reflogs->nr == 0) {
161                         struct object_id oid;
162                         char *b;
163                         int ret = dwim_log(branch, strlen(branch),
164                                            &oid, &b);
165                         if (ret > 1)
166                                 free(b);
167                         else if (ret == 1) {
168                                 free_complete_reflog(reflogs);
169                                 free(branch);
170                                 branch = b;
171                                 reflogs = read_complete_reflog(branch);
172                         }
173                 }
174                 if (!reflogs || reflogs->nr == 0) {
175                         free_complete_reflog(reflogs);
176                         free(branch);
177                         return -1;
178                 }
179                 string_list_insert(&info->complete_reflogs, branch)->util
180                         = reflogs;
181         }
182         free(branch);
183
184         commit_reflog = xcalloc(1, sizeof(struct commit_reflog));
185         if (recno < 0) {
186                 commit_reflog->recno = get_reflog_recno_by_time(reflogs, timestamp);
187                 if (commit_reflog->recno < 0) {
188                         free(commit_reflog);
189                         return -1;
190                 }
191         } else
192                 commit_reflog->recno = reflogs->nr - recno - 1;
193         commit_reflog->selector = selector;
194         commit_reflog->reflogs = reflogs;
195
196         ALLOC_GROW(info->logs, info->nr + 1, info->alloc);
197         info->logs[info->nr++] = commit_reflog;
198
199         return 0;
200 }
201
202 void get_reflog_selector(struct strbuf *sb,
203                          struct reflog_walk_info *reflog_info,
204                          const struct date_mode *dmode, int force_date,
205                          int shorten)
206 {
207         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
208         struct reflog_info *info;
209         const char *printed_ref;
210
211         if (!commit_reflog)
212                 return;
213
214         if (shorten) {
215                 if (!commit_reflog->reflogs->short_ref)
216                         commit_reflog->reflogs->short_ref
217                                 = shorten_unambiguous_ref(commit_reflog->reflogs->ref, 0);
218                 printed_ref = commit_reflog->reflogs->short_ref;
219         } else {
220                 printed_ref = commit_reflog->reflogs->ref;
221         }
222
223         strbuf_addf(sb, "%s@{", printed_ref);
224         if (commit_reflog->selector == SELECTOR_DATE ||
225             (commit_reflog->selector == SELECTOR_NONE && force_date)) {
226                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
227                 strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));
228         } else {
229                 strbuf_addf(sb, "%d", commit_reflog->reflogs->nr
230                             - 2 - commit_reflog->recno);
231         }
232
233         strbuf_addch(sb, '}');
234 }
235
236 void get_reflog_message(struct strbuf *sb,
237                         struct reflog_walk_info *reflog_info)
238 {
239         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
240         struct reflog_info *info;
241         size_t len;
242
243         if (!commit_reflog)
244                 return;
245
246         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
247         len = strlen(info->message);
248         if (len > 0)
249                 len--; /* strip away trailing newline */
250         strbuf_add(sb, info->message, len);
251 }
252
253 const char *get_reflog_ident(struct reflog_walk_info *reflog_info)
254 {
255         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
256         struct reflog_info *info;
257
258         if (!commit_reflog)
259                 return NULL;
260
261         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
262         return info->email;
263 }
264
265 timestamp_t get_reflog_timestamp(struct reflog_walk_info *reflog_info)
266 {
267         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
268         struct reflog_info *info;
269
270         if (!commit_reflog)
271                 return 0;
272
273         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
274         return info->timestamp;
275 }
276
277 void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,
278                          const struct date_mode *dmode, int force_date)
279 {
280         if (reflog_info && reflog_info->last_commit_reflog) {
281                 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
282                 struct reflog_info *info;
283                 struct strbuf selector = STRBUF_INIT;
284
285                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
286                 get_reflog_selector(&selector, reflog_info, dmode, force_date, 0);
287                 if (oneline) {
288                         printf("%s: %s", selector.buf, info->message);
289                 }
290                 else {
291                         printf("Reflog: %s (%s)\nReflog message: %s",
292                                selector.buf, info->email, info->message);
293                 }
294
295                 strbuf_release(&selector);
296         }
297 }
298
299 int reflog_walk_empty(struct reflog_walk_info *info)
300 {
301         return !info || !info->nr;
302 }
303
304 static struct commit *next_reflog_commit(struct commit_reflog *log)
305 {
306         for (; log->recno >= 0; log->recno--) {
307                 struct reflog_info *entry = &log->reflogs->items[log->recno];
308                 struct object *obj = parse_object(the_repository,
309                                                   &entry->noid);
310
311                 if (obj && obj->type == OBJ_COMMIT)
312                         return (struct commit *)obj;
313         }
314         return NULL;
315 }
316
317 static timestamp_t log_timestamp(struct commit_reflog *log)
318 {
319         return log->reflogs->items[log->recno].timestamp;
320 }
321
322 struct commit *next_reflog_entry(struct reflog_walk_info *walk)
323 {
324         struct commit_reflog *best = NULL;
325         struct commit *best_commit = NULL;
326         size_t i;
327
328         for (i = 0; i < walk->nr; i++) {
329                 struct commit_reflog *log = walk->logs[i];
330                 struct commit *commit = next_reflog_commit(log);
331
332                 if (!commit)
333                         continue;
334
335                 if (!best || log_timestamp(log) > log_timestamp(best)) {
336                         best = log;
337                         best_commit = commit;
338                 }
339         }
340
341         if (best) {
342                 best->recno--;
343                 walk->last_commit_reflog = best;
344                 return best_commit;
345         }
346
347         return NULL;
348 }