diff: test precedence of external diff drivers
[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         if (array->nr >= array->alloc) {
30                 array->alloc = alloc_nr(array->nr + 1);
31                 array->items = xrealloc(array->items, array->alloc *
32                         sizeof(struct reflog_info));
33         }
34         item = array->items + array->nr;
35         memcpy(item->osha1, osha1, 20);
36         memcpy(item->nsha1, nsha1, 20);
37         item->email = xstrdup(email);
38         item->timestamp = timestamp;
39         item->tz = tz;
40         item->message = xstrdup(message);
41         array->nr++;
42         return 0;
43 }
44
45 static struct complete_reflogs *read_complete_reflog(const char *ref)
46 {
47         struct complete_reflogs *reflogs =
48                 xcalloc(sizeof(struct complete_reflogs), 1);
49         reflogs->ref = xstrdup(ref);
50         for_each_reflog_ent(ref, read_one_reflog, reflogs);
51         if (reflogs->nr == 0) {
52                 unsigned char sha1[20];
53                 const char *name;
54                 void *name_to_free;
55                 name = name_to_free = resolve_refdup(ref, sha1, 1, NULL);
56                 if (name) {
57                         for_each_reflog_ent(name, read_one_reflog, reflogs);
58                         free(name_to_free);
59                 }
60         }
61         if (reflogs->nr == 0) {
62                 int len = strlen(ref);
63                 char *refname = xmalloc(len + 12);
64                 sprintf(refname, "refs/%s", ref);
65                 for_each_reflog_ent(refname, read_one_reflog, reflogs);
66                 if (reflogs->nr == 0) {
67                         sprintf(refname, "refs/heads/%s", ref);
68                         for_each_reflog_ent(refname, read_one_reflog, reflogs);
69                 }
70                 free(refname);
71         }
72         return reflogs;
73 }
74
75 static int get_reflog_recno_by_time(struct complete_reflogs *array,
76         unsigned long timestamp)
77 {
78         int i;
79         for (i = array->nr - 1; i >= 0; i--)
80                 if (timestamp >= array->items[i].timestamp)
81                         return i;
82         return -1;
83 }
84
85 struct commit_info_lifo {
86         struct commit_info {
87                 struct commit *commit;
88                 void *util;
89         } *items;
90         int nr, alloc;
91 };
92
93 static struct commit_info *get_commit_info(struct commit *commit,
94                 struct commit_info_lifo *lifo, int pop)
95 {
96         int i;
97         for (i = 0; i < lifo->nr; i++)
98                 if (lifo->items[i].commit == commit) {
99                         struct commit_info *result = &lifo->items[i];
100                         if (pop) {
101                                 if (i + 1 < lifo->nr)
102                                         memmove(lifo->items + i,
103                                                 lifo->items + i + 1,
104                                                 (lifo->nr - i) *
105                                                 sizeof(struct commit_info));
106                                 lifo->nr--;
107                         }
108                         return result;
109                 }
110         return NULL;
111 }
112
113 static void add_commit_info(struct commit *commit, void *util,
114                 struct commit_info_lifo *lifo)
115 {
116         struct commit_info *info;
117         if (lifo->nr >= lifo->alloc) {
118                 lifo->alloc = alloc_nr(lifo->nr + 1);
119                 lifo->items = xrealloc(lifo->items,
120                         lifo->alloc * sizeof(struct commit_info));
121         }
122         info = lifo->items + lifo->nr;
123         info->commit = commit;
124         info->util = util;
125         lifo->nr++;
126 }
127
128 struct commit_reflog {
129         int flag, recno;
130         struct complete_reflogs *reflogs;
131 };
132
133 struct reflog_walk_info {
134         struct commit_info_lifo reflogs;
135         struct string_list complete_reflogs;
136         struct commit_reflog *last_commit_reflog;
137 };
138
139 void init_reflog_walk(struct reflog_walk_info** info)
140 {
141         *info = xcalloc(sizeof(struct reflog_walk_info), 1);
142 }
143
144 int add_reflog_for_walk(struct reflog_walk_info *info,
145                 struct commit *commit, const char *name)
146 {
147         unsigned long timestamp = 0;
148         int recno = -1;
149         struct string_list_item *item;
150         struct complete_reflogs *reflogs;
151         char *branch, *at = strchr(name, '@');
152         struct commit_reflog *commit_reflog;
153
154         if (commit->object.flags & UNINTERESTING)
155                 die ("Cannot walk reflogs for %s", name);
156
157         branch = xstrdup(name);
158         if (at && at[1] == '{') {
159                 char *ep;
160                 branch[at - name] = '\0';
161                 recno = strtoul(at + 2, &ep, 10);
162                 if (*ep != '}') {
163                         recno = -1;
164                         timestamp = approxidate(at + 2);
165                 }
166         } else
167                 recno = 0;
168
169         item = string_list_lookup(&info->complete_reflogs, branch);
170         if (item)
171                 reflogs = item->util;
172         else {
173                 if (*branch == '\0') {
174                         unsigned char sha1[20];
175                         free(branch);
176                         branch = resolve_refdup("HEAD", sha1, 0, NULL);
177                         if (!branch)
178                                 die ("No current branch");
179
180                 }
181                 reflogs = read_complete_reflog(branch);
182                 if (!reflogs || reflogs->nr == 0) {
183                         unsigned char sha1[20];
184                         char *b;
185                         if (dwim_log(branch, strlen(branch), sha1, &b) == 1) {
186                                 if (reflogs) {
187                                         free(reflogs->ref);
188                                         free(reflogs);
189                                 }
190                                 free(branch);
191                                 branch = b;
192                                 reflogs = read_complete_reflog(branch);
193                         }
194                 }
195                 if (!reflogs || reflogs->nr == 0)
196                         return -1;
197                 string_list_insert(&info->complete_reflogs, branch)->util
198                         = reflogs;
199         }
200
201         commit_reflog = xcalloc(sizeof(struct commit_reflog), 1);
202         if (recno < 0) {
203                 commit_reflog->flag = 1;
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->reflogs = reflogs;
213
214         add_commit_info(commit, commit_reflog, &info->reflogs);
215         return 0;
216 }
217
218 void fake_reflog_parent(struct reflog_walk_info *info, struct commit *commit)
219 {
220         struct commit_info *commit_info =
221                 get_commit_info(commit, &info->reflogs, 0);
222         struct commit_reflog *commit_reflog;
223         struct reflog_info *reflog;
224
225         info->last_commit_reflog = NULL;
226         if (!commit_info)
227                 return;
228
229         commit_reflog = commit_info->util;
230         if (commit_reflog->recno < 0) {
231                 commit->parents = NULL;
232                 return;
233         }
234
235         reflog = &commit_reflog->reflogs->items[commit_reflog->recno];
236         info->last_commit_reflog = commit_reflog;
237         commit_reflog->recno--;
238         commit_info->commit = (struct commit *)parse_object(reflog->osha1);
239         if (!commit_info->commit) {
240                 commit->parents = NULL;
241                 return;
242         }
243
244         commit->parents = xcalloc(sizeof(struct commit_list), 1);
245         commit->parents->item = commit_info->commit;
246 }
247
248 void get_reflog_selector(struct strbuf *sb,
249                          struct reflog_walk_info *reflog_info,
250                          enum date_mode dmode,
251                          int shorten)
252 {
253         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
254         struct reflog_info *info;
255         const char *printed_ref;
256
257         if (!commit_reflog)
258                 return;
259
260         if (shorten) {
261                 if (!commit_reflog->reflogs->short_ref)
262                         commit_reflog->reflogs->short_ref
263                                 = shorten_unambiguous_ref(commit_reflog->reflogs->ref, 0);
264                 printed_ref = commit_reflog->reflogs->short_ref;
265         } else {
266                 printed_ref = commit_reflog->reflogs->ref;
267         }
268
269         strbuf_addf(sb, "%s@{", printed_ref);
270         if (commit_reflog->flag || dmode) {
271                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
272                 strbuf_addstr(sb, show_date(info->timestamp, info->tz, dmode));
273         } else {
274                 strbuf_addf(sb, "%d", commit_reflog->reflogs->nr
275                             - 2 - commit_reflog->recno);
276         }
277
278         strbuf_addch(sb, '}');
279 }
280
281 void get_reflog_message(struct strbuf *sb,
282                         struct reflog_walk_info *reflog_info)
283 {
284         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
285         struct reflog_info *info;
286         size_t len;
287
288         if (!commit_reflog)
289                 return;
290
291         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
292         len = strlen(info->message);
293         if (len > 0)
294                 len--; /* strip away trailing newline */
295         strbuf_add(sb, info->message, len);
296 }
297
298 const char *get_reflog_ident(struct reflog_walk_info *reflog_info)
299 {
300         struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
301         struct reflog_info *info;
302
303         if (!commit_reflog)
304                 return NULL;
305
306         info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
307         return info->email;
308 }
309
310 void show_reflog_message(struct reflog_walk_info *reflog_info, int oneline,
311         enum date_mode dmode)
312 {
313         if (reflog_info && reflog_info->last_commit_reflog) {
314                 struct commit_reflog *commit_reflog = reflog_info->last_commit_reflog;
315                 struct reflog_info *info;
316                 struct strbuf selector = STRBUF_INIT;
317
318                 info = &commit_reflog->reflogs->items[commit_reflog->recno+1];
319                 get_reflog_selector(&selector, reflog_info, dmode, 0);
320                 if (oneline) {
321                         printf("%s: %s", selector.buf, info->message);
322                 }
323                 else {
324                         printf("Reflog: %s (%s)\nReflog message: %s",
325                                selector.buf, info->email, info->message);
326                 }
327
328                 strbuf_release(&selector);
329         }
330 }