strbuf_read(): skip unnecessary strbuf_grow() at eof
[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                 unsigned char osha1[20], nsha1[20];
14                 char *email;
15                 unsigned long timestamp;
16                 int tz;
17                 char *message;
18         } *items;
19         int nr, alloc;
20 };
21
22 static int read_one_reflog(unsigned char *osha1, unsigned char *nsha1,
23                 const char *email, unsigned long 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         hashcpy(item->osha1, osha1);
32         hashcpy(item->nsha1, nsha1);
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 struct complete_reflogs *read_complete_reflog(const char *ref)
42 {
43         struct complete_reflogs *reflogs =
44                 xcalloc(1, sizeof(struct complete_reflogs));
45         reflogs->ref = xstrdup(ref);
46         for_each_reflog_ent(ref, read_one_reflog, reflogs);
47         if (reflogs->nr == 0) {
48                 unsigned char sha1[20];
49                 const char *name;
50                 void *name_to_free;
51                 name = name_to_free = resolve_refdup(ref, sha1, 1, NULL);
52                 if (name) {
53                         for_each_reflog_ent(name, read_one_reflog, reflogs);
54                         free(name_to_free);
55                 }
56         }
57         if (reflogs->nr == 0) {
58                 int len = strlen(ref);
59                 char *refname = xmalloc(len + 12);
60                 sprintf(refname, "refs/%s", ref);
61                 for_each_reflog_ent(refname, read_one_reflog, reflogs);
62                 if (reflogs->nr == 0) {
63                         sprintf(refname, "refs/heads/%s", ref);
64                         for_each_reflog_ent(refname, read_one_reflog, reflogs);
65                 }
66                 free(refname);
67         }
68         return reflogs;
69 }
70
71 static int get_reflog_recno_by_time(struct complete_reflogs *array,
72         unsigned long timestamp)
73 {
74         int i;
75         for (i = array->nr - 1; i >= 0; i--)
76                 if (timestamp >= array->items[i].timestamp)
77                         return i;
78         return -1;
79 }
80
81 struct commit_info_lifo {
82         struct commit_info {
83                 struct commit *commit;
84                 void *util;
85         } *items;
86         int nr, alloc;
87 };
88
89 static struct commit_info *get_commit_info(struct commit *commit,
90                 struct commit_info_lifo *lifo, int pop)
91 {
92         int i;
93         for (i = 0; i < lifo->nr; i++)
94                 if (lifo->items[i].commit == commit) {
95                         struct commit_info *result = &lifo->items[i];
96                         if (pop) {
97                                 if (i + 1 < lifo->nr)
98                                         memmove(lifo->items + i,
99                                                 lifo->items + i + 1,
100                                                 (lifo->nr - i) *
101                                                 sizeof(struct commit_info));
102                                 lifo->nr--;
103                         }
104                         return result;
105                 }
106         return NULL;
107 }
108
109 static void add_commit_info(struct commit *commit, void *util,
110                 struct commit_info_lifo *lifo)
111 {
112         struct commit_info *info;
113         ALLOC_GROW(lifo->items, lifo->nr + 1, lifo->alloc);
114         info = lifo->items + lifo->nr;
115         info->commit = commit;
116         info->util = util;
117         lifo->nr++;
118 }
119
120 struct commit_reflog {
121         int recno;
122         enum selector_type {
123                 SELECTOR_NONE,
124                 SELECTOR_INDEX,
125                 SELECTOR_DATE
126         } selector;
127         struct complete_reflogs *reflogs;
128 };
129
130 struct reflog_walk_info {
131         struct commit_info_lifo reflogs;
132         struct string_list complete_reflogs;
133         struct commit_reflog *last_commit_reflog;
134 };
135
136 void init_reflog_walk(struct reflog_walk_info** info)
137 {
138         *info = xcalloc(1, sizeof(struct reflog_walk_info));
139 }
140
141 int add_reflog_for_walk(struct reflog_walk_info *info,
142                 struct commit *commit, const char *name)
143 {
144         unsigned long timestamp = 0;
145         int recno = -1;
146         struct string_list_item *item;
147         struct complete_reflogs *reflogs;
148         char *branch, *at = strchr(name, '@');
149         struct commit_reflog *commit_reflog;
150         enum selector_type selector = SELECTOR_NONE;
151
152         if (commit->object.flags & UNINTERESTING)
153                 die ("Cannot walk reflogs for %s", name);
154
155         branch = xstrdup(name);
156         if (at && at[1] == '{') {
157                 char *ep;
158                 branch[at - name] = '\0';
159                 recno = strtoul(at + 2, &ep, 10);
160                 if (*ep != '}') {
161                         recno = -1;
162                         timestamp = approxidate(at + 2);
163                         selector = SELECTOR_DATE;
164                 }
165                 else
166                         selector = SELECTOR_INDEX;
167         } else
168                 recno = 0;
169
170         item = string_list_lookup(&info->complete_reflogs, branch);
171         if (item)
172                 reflogs = item->util;
173         else {
174                 if (*branch == '\0') {
175                         unsigned char sha1[20];
176                         free(branch);
177                         branch = resolve_refdup("HEAD", sha1, 0, NULL);
178                         if (!branch)
179                                 die ("No current branch");
180
181                 }
182                 reflogs = read_complete_reflog(branch);
183                 if (!reflogs || reflogs->nr == 0) {
184                         unsigned char sha1[20];
185                         char *b;
186                         if (dwim_log(branch, strlen(branch), sha1, &b) == 1) {
187                                 if (reflogs) {
188                                         free(reflogs->ref);
189                                         free(reflogs);
190                                 }
191                                 free(branch);
192                                 branch = b;
193                                 reflogs = read_complete_reflog(branch);
194                         }
195                 }
196                 if (!reflogs || reflogs->nr == 0)
197                         return -1;
198                 string_list_insert(&info->complete_reflogs, branch)->util
199                         = reflogs;
200         }
201
202         commit_reflog = xcalloc(1, sizeof(struct commit_reflog));
203         if (recno < 0) {
204                 commit_reflog->recno = get_reflog_recno_by_time(reflogs, timestamp);
205                 if (commit_reflog->recno < 0) {
206                         free(branch);
207                         free(commit_reflog);
208                         return -1;
209                 }
210         } else
211                 commit_reflog->recno = reflogs->nr - recno - 1;
212         commit_reflog->selector = selector;
213         commit_reflog->reflogs = reflogs;
214
215         add_commit_info(commit, commit_reflog, &info->reflogs);
216         return 0;
217 }
218
219 void fake_reflog_parent(struct reflog_walk_info *info, struct commit *commit)
220 {
221         struct commit_info *commit_info =
222                 get_commit_info(commit, &info->reflogs, 0);
223         struct commit_reflog *commit_reflog;
224         struct reflog_info *reflog;
225
226         info->last_commit_reflog = NULL;
227         if (!commit_info)
228                 return;
229
230         commit_reflog = commit_info->util;
231         if (commit_reflog->recno < 0) {
232                 commit->parents = NULL;
233                 return;
234         }
235
236         reflog = &commit_reflog->reflogs->items[commit_reflog->recno];
237         info->last_commit_reflog = commit_reflog;
238         commit_reflog->recno--;
239         commit_info->commit = (struct commit *)parse_object(reflog->osha1);
240         if (!commit_info->commit) {
241                 commit->parents = NULL;
242                 return;
243         }
244
245         commit->parents = xcalloc(1, sizeof(struct commit_list));
246         commit->parents->item = commit_info->commit;
247 }
248
249 void get_reflog_selector(struct strbuf *sb,
250                          struct reflog_walk_info *reflog_info,
251                          enum date_mode dmode, int force_date,
252                          int shorten)
253 {
254         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
255         struct reflog_info *info;
256         const char *printed_ref;
257
258         if (!commit_reflog)
259                 return;
260
261         if (shorten) {
262                 if (!commit_reflog->reflogs->short_ref)
263                         commit_reflog->reflogs->short_ref
264                                 = shorten_unambiguous_ref(commit_reflog->reflogs->ref, 0);
265                 printed_ref = commit_reflog->reflogs->short_ref;
266         } else {
267                 printed_ref = commit_reflog->reflogs->ref;
268         }
269
270         strbuf_addf(sb, "%s@{", printed_ref);
271         if (commit_reflog->selector == SELECTOR_DATE ||
272             (commit_reflog->selector == SELECTOR_NONE && force_date)) {
273                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
274                 strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));
275         } else {
276                 strbuf_addf(sb, "%d", commit_reflog->reflogs->nr
277                             - 2 - commit_reflog->recno);
278         }
279
280         strbuf_addch(sb, '}');
281 }
282
283 void get_reflog_message(struct strbuf *sb,
284                         struct reflog_walk_info *reflog_info)
285 {
286         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
287         struct reflog_info *info;
288         size_t len;
289
290         if (!commit_reflog)
291                 return;
292
293         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
294         len = strlen(info->message);
295         if (len > 0)
296                 len--; /* strip away trailing newline */
297         strbuf_add(sb, info->message, len);
298 }
299
300 const char *get_reflog_ident(struct reflog_walk_info *reflog_info)
301 {
302         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
303         struct reflog_info *info;
304
305         if (!commit_reflog)
306                 return NULL;
307
308         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
309         return info->email;
310 }
311
312 void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,
313                          enum date_mode dmode, int force_date)
314 {
315         if (reflog_info && reflog_info->last_commit_reflog) {
316                 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
317                 struct reflog_info *info;
318                 struct strbuf selector = STRBUF_INIT;
319
320                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
321                 get_reflog_selector(&selector, reflog_info, dmode, force_date, 0);
322                 if (oneline) {
323                         printf("%s: %s", selector.buf, info->message);
324                 }
325                 else {
326                         printf("Reflog: %s (%s)\nReflog message: %s",
327                                selector.buf, info->email, info->message);
328                 }
329
330                 strbuf_release(&selector);
331         }
332 }