t7004: move limited stack prereq to test-lib
[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_reflog {
98         int recno;
99         enum selector_type {
100                 SELECTOR_NONE,
101                 SELECTOR_INDEX,
102                 SELECTOR_DATE
103         } selector;
104         struct complete_reflogs *reflogs;
105 };
106
107 struct reflog_walk_info {
108         struct commit_reflog **logs;
109         size_t nr, alloc;
110         struct string_list complete_reflogs;
111         struct commit_reflog *last_commit_reflog;
112 };
113
114 void init_reflog_walk(struct reflog_walk_info **info)
115 {
116         *info = xcalloc(1, sizeof(struct reflog_walk_info));
117         (*info)->complete_reflogs.strdup_strings = 1;
118 }
119
120 int add_reflog_for_walk(struct reflog_walk_info *info,
121                 struct commit *commit, const char *name)
122 {
123         timestamp_t timestamp = 0;
124         int recno = -1;
125         struct string_list_item *item;
126         struct complete_reflogs *reflogs;
127         char *branch, *at = strchr(name, '@');
128         struct commit_reflog *commit_reflog;
129         enum selector_type selector = SELECTOR_NONE;
130
131         if (commit->object.flags & UNINTERESTING)
132                 die ("Cannot walk reflogs for %s", name);
133
134         branch = xstrdup(name);
135         if (at && at[1] == '{') {
136                 char *ep;
137                 branch[at - name] = '\0';
138                 recno = strtoul(at + 2, &ep, 10);
139                 if (*ep != '}') {
140                         recno = -1;
141                         timestamp = approxidate(at + 2);
142                         selector = SELECTOR_DATE;
143                 }
144                 else
145                         selector = SELECTOR_INDEX;
146         } else
147                 recno = 0;
148
149         item = string_list_lookup(&info->complete_reflogs, branch);
150         if (item)
151                 reflogs = item->util;
152         else {
153                 if (*branch == '\0') {
154                         struct object_id oid;
155                         free(branch);
156                         branch = resolve_refdup("HEAD", 0, oid.hash, NULL);
157                         if (!branch)
158                                 die ("No current branch");
159
160                 }
161                 reflogs = read_complete_reflog(branch);
162                 if (!reflogs || reflogs->nr == 0) {
163                         struct object_id oid;
164                         char *b;
165                         int ret = dwim_log(branch, strlen(branch),
166                                            oid.hash, &b);
167                         if (ret > 1)
168                                 free(b);
169                         else if (ret == 1) {
170                                 free_complete_reflog(reflogs);
171                                 free(branch);
172                                 branch = b;
173                                 reflogs = read_complete_reflog(branch);
174                         }
175                 }
176                 if (!reflogs || reflogs->nr == 0) {
177                         free_complete_reflog(reflogs);
178                         free(branch);
179                         return -1;
180                 }
181                 string_list_insert(&info->complete_reflogs, branch)->util
182                         = reflogs;
183         }
184         free(branch);
185
186         commit_reflog = xcalloc(1, sizeof(struct commit_reflog));
187         if (recno < 0) {
188                 commit_reflog->recno = get_reflog_recno_by_time(reflogs, timestamp);
189                 if (commit_reflog->recno < 0) {
190                         free(commit_reflog);
191                         return -1;
192                 }
193         } else
194                 commit_reflog->recno = reflogs->nr - recno - 1;
195         commit_reflog->selector = selector;
196         commit_reflog->reflogs = reflogs;
197
198         ALLOC_GROW(info->logs, info->nr + 1, info->alloc);
199         info->logs[info->nr++] = commit_reflog;
200
201         return 0;
202 }
203
204 void get_reflog_selector(struct strbuf *sb,
205                          struct reflog_walk_info *reflog_info,
206                          const struct date_mode *dmode, int force_date,
207                          int shorten)
208 {
209         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
210         struct reflog_info *info;
211         const char *printed_ref;
212
213         if (!commit_reflog)
214                 return;
215
216         if (shorten) {
217                 if (!commit_reflog->reflogs->short_ref)
218                         commit_reflog->reflogs->short_ref
219                                 = shorten_unambiguous_ref(commit_reflog->reflogs->ref, 0);
220                 printed_ref = commit_reflog->reflogs->short_ref;
221         } else {
222                 printed_ref = commit_reflog->reflogs->ref;
223         }
224
225         strbuf_addf(sb, "%s@{", printed_ref);
226         if (commit_reflog->selector == SELECTOR_DATE ||
227             (commit_reflog->selector == SELECTOR_NONE && force_date)) {
228                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
229                 strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));
230         } else {
231                 strbuf_addf(sb, "%d", commit_reflog->reflogs->nr
232                             - 2 - commit_reflog->recno);
233         }
234
235         strbuf_addch(sb, '}');
236 }
237
238 void get_reflog_message(struct strbuf *sb,
239                         struct reflog_walk_info *reflog_info)
240 {
241         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
242         struct reflog_info *info;
243         size_t len;
244
245         if (!commit_reflog)
246                 return;
247
248         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
249         len = strlen(info->message);
250         if (len > 0)
251                 len--; /* strip away trailing newline */
252         strbuf_add(sb, info->message, len);
253 }
254
255 const char *get_reflog_ident(struct reflog_walk_info *reflog_info)
256 {
257         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
258         struct reflog_info *info;
259
260         if (!commit_reflog)
261                 return NULL;
262
263         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
264         return info->email;
265 }
266
267 timestamp_t get_reflog_timestamp(struct reflog_walk_info *reflog_info)
268 {
269         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
270         struct reflog_info *info;
271
272         if (!commit_reflog)
273                 return 0;
274
275         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
276         return info->timestamp;
277 }
278
279 void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,
280                          const struct date_mode *dmode, int force_date)
281 {
282         if (reflog_info && reflog_info->last_commit_reflog) {
283                 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
284                 struct reflog_info *info;
285                 struct strbuf selector = STRBUF_INIT;
286
287                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
288                 get_reflog_selector(&selector, reflog_info, dmode, force_date, 0);
289                 if (oneline) {
290                         printf("%s: %s", selector.buf, info->message);
291                 }
292                 else {
293                         printf("Reflog: %s (%s)\nReflog message: %s",
294                                selector.buf, info->email, info->message);
295                 }
296
297                 strbuf_release(&selector);
298         }
299 }
300
301 int reflog_walk_empty(struct reflog_walk_info *info)
302 {
303         return !info || !info->nr;
304 }
305
306 static struct commit *next_reflog_commit(struct commit_reflog *log)
307 {
308         for (; log->recno >= 0; log->recno--) {
309                 struct reflog_info *entry = &log->reflogs->items[log->recno];
310                 struct object *obj = parse_object(&entry->noid);
311
312                 if (obj && obj->type == OBJ_COMMIT)
313                         return (struct commit *)obj;
314         }
315         return NULL;
316 }
317
318 static timestamp_t log_timestamp(struct commit_reflog *log)
319 {
320         return log->reflogs->items[log->recno].timestamp;
321 }
322
323 struct commit *next_reflog_entry(struct reflog_walk_info *walk)
324 {
325         struct commit_reflog *best = NULL;
326         struct commit *best_commit = NULL;
327         size_t i;
328
329         for (i = 0; i < walk->nr; i++) {
330                 struct commit_reflog *log = walk->logs[i];
331                 struct commit *commit = next_reflog_commit(log);
332
333                 if (!commit)
334                         continue;
335
336                 if (!best || log_timestamp(log) > log_timestamp(best)) {
337                         best = log;
338                         best_commit = commit;
339                 }
340         }
341
342         if (best) {
343                 best->recno--;
344                 walk->last_commit_reflog = best;
345                 return best_commit;
346         }
347
348         return NULL;
349 }