Merge branch 'bc/send-email-auto-cte'
[git] / walker.c
1 #include "cache.h"
2 #include "walker.h"
3 #include "object-store.h"
4 #include "commit.h"
5 #include "tree.h"
6 #include "tree-walk.h"
7 #include "tag.h"
8 #include "blob.h"
9 #include "refs.h"
10
11 static struct object_id current_commit_oid;
12
13 void walker_say(struct walker *walker, const char *fmt, ...)
14 {
15         if (walker->get_verbosely) {
16                 va_list ap;
17                 va_start(ap, fmt);
18                 vfprintf(stderr, fmt, ap);
19                 va_end(ap);
20         }
21 }
22
23 static void report_missing(const struct object *obj)
24 {
25         fprintf(stderr, "Cannot obtain needed %s %s\n",
26                 obj->type ? type_name(obj->type): "object",
27                 oid_to_hex(&obj->oid));
28         if (!is_null_oid(&current_commit_oid))
29                 fprintf(stderr, "while processing commit %s.\n",
30                         oid_to_hex(&current_commit_oid));
31 }
32
33 static int process(struct walker *walker, struct object *obj);
34
35 static int process_tree(struct walker *walker, struct tree *tree)
36 {
37         struct tree_desc desc;
38         struct name_entry entry;
39
40         if (parse_tree(tree))
41                 return -1;
42
43         init_tree_desc(&desc, tree->buffer, tree->size);
44         while (tree_entry(&desc, &entry)) {
45                 struct object *obj = NULL;
46
47                 /* submodule commits are not stored in the superproject */
48                 if (S_ISGITLINK(entry.mode))
49                         continue;
50                 if (S_ISDIR(entry.mode)) {
51                         struct tree *tree = lookup_tree(entry.oid);
52                         if (tree)
53                                 obj = &tree->object;
54                 }
55                 else {
56                         struct blob *blob = lookup_blob(entry.oid);
57                         if (blob)
58                                 obj = &blob->object;
59                 }
60                 if (!obj || process(walker, obj))
61                         return -1;
62         }
63         free_tree_buffer(tree);
64         return 0;
65 }
66
67 /* Remember to update object flag allocation in object.h */
68 #define COMPLETE        (1U << 0)
69 #define SEEN            (1U << 1)
70 #define TO_SCAN         (1U << 2)
71
72 static struct commit_list *complete = NULL;
73
74 static int process_commit(struct walker *walker, struct commit *commit)
75 {
76         struct commit_list *parents;
77
78         if (parse_commit(commit))
79                 return -1;
80
81         while (complete && complete->item->date >= commit->date) {
82                 pop_most_recent_commit(&complete, COMPLETE);
83         }
84
85         if (commit->object.flags & COMPLETE)
86                 return 0;
87
88         oidcpy(&current_commit_oid, &commit->object.oid);
89
90         walker_say(walker, "walk %s\n", oid_to_hex(&commit->object.oid));
91
92         if (process(walker, &get_commit_tree(commit)->object))
93                 return -1;
94
95         for (parents = commit->parents; parents; parents = parents->next) {
96                 if (process(walker, &parents->item->object))
97                         return -1;
98         }
99
100         return 0;
101 }
102
103 static int process_tag(struct walker *walker, struct tag *tag)
104 {
105         if (parse_tag(tag))
106                 return -1;
107         return process(walker, tag->tagged);
108 }
109
110 static struct object_list *process_queue = NULL;
111 static struct object_list **process_queue_end = &process_queue;
112
113 static int process_object(struct walker *walker, struct object *obj)
114 {
115         if (obj->type == OBJ_COMMIT) {
116                 if (process_commit(walker, (struct commit *)obj))
117                         return -1;
118                 return 0;
119         }
120         if (obj->type == OBJ_TREE) {
121                 if (process_tree(walker, (struct tree *)obj))
122                         return -1;
123                 return 0;
124         }
125         if (obj->type == OBJ_BLOB) {
126                 return 0;
127         }
128         if (obj->type == OBJ_TAG) {
129                 if (process_tag(walker, (struct tag *)obj))
130                         return -1;
131                 return 0;
132         }
133         return error("Unable to determine requirements "
134                      "of type %s for %s",
135                      type_name(obj->type), oid_to_hex(&obj->oid));
136 }
137
138 static int process(struct walker *walker, struct object *obj)
139 {
140         if (obj->flags & SEEN)
141                 return 0;
142         obj->flags |= SEEN;
143
144         if (has_object_file(&obj->oid)) {
145                 /* We already have it, so we should scan it now. */
146                 obj->flags |= TO_SCAN;
147         }
148         else {
149                 if (obj->flags & COMPLETE)
150                         return 0;
151                 walker->prefetch(walker, obj->oid.hash);
152         }
153
154         object_list_insert(obj, process_queue_end);
155         process_queue_end = &(*process_queue_end)->next;
156         return 0;
157 }
158
159 static int loop(struct walker *walker)
160 {
161         struct object_list *elem;
162
163         while (process_queue) {
164                 struct object *obj = process_queue->item;
165                 elem = process_queue;
166                 process_queue = elem->next;
167                 free(elem);
168                 if (!process_queue)
169                         process_queue_end = &process_queue;
170
171                 /* If we are not scanning this object, we placed it in
172                  * the queue because we needed to fetch it first.
173                  */
174                 if (! (obj->flags & TO_SCAN)) {
175                         if (walker->fetch(walker, obj->oid.hash)) {
176                                 report_missing(obj);
177                                 return -1;
178                         }
179                 }
180                 if (!obj->type)
181                         parse_object(&obj->oid);
182                 if (process_object(walker, obj))
183                         return -1;
184         }
185         return 0;
186 }
187
188 static int interpret_target(struct walker *walker, char *target, struct object_id *oid)
189 {
190         if (!get_oid_hex(target, oid))
191                 return 0;
192         if (!check_refname_format(target, 0)) {
193                 struct ref *ref = alloc_ref(target);
194                 if (!walker->fetch_ref(walker, ref)) {
195                         oidcpy(oid, &ref->old_oid);
196                         free(ref);
197                         return 0;
198                 }
199                 free(ref);
200         }
201         return -1;
202 }
203
204 static int mark_complete(const char *path, const struct object_id *oid,
205                          int flag, void *cb_data)
206 {
207         struct commit *commit = lookup_commit_reference_gently(oid, 1);
208
209         if (commit) {
210                 commit->object.flags |= COMPLETE;
211                 commit_list_insert(commit, &complete);
212         }
213         return 0;
214 }
215
216 int walker_targets_stdin(char ***target, const char ***write_ref)
217 {
218         int targets = 0, targets_alloc = 0;
219         struct strbuf buf = STRBUF_INIT;
220         *target = NULL; *write_ref = NULL;
221         while (1) {
222                 char *rf_one = NULL;
223                 char *tg_one;
224
225                 if (strbuf_getline_lf(&buf, stdin) == EOF)
226                         break;
227                 tg_one = buf.buf;
228                 rf_one = strchr(tg_one, '\t');
229                 if (rf_one)
230                         *rf_one++ = 0;
231
232                 if (targets >= targets_alloc) {
233                         targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
234                         REALLOC_ARRAY(*target, targets_alloc);
235                         REALLOC_ARRAY(*write_ref, targets_alloc);
236                 }
237                 (*target)[targets] = xstrdup(tg_one);
238                 (*write_ref)[targets] = xstrdup_or_null(rf_one);
239                 targets++;
240         }
241         strbuf_release(&buf);
242         return targets;
243 }
244
245 void walker_targets_free(int targets, char **target, const char **write_ref)
246 {
247         while (targets--) {
248                 free(target[targets]);
249                 if (write_ref)
250                         free((char *) write_ref[targets]);
251         }
252 }
253
254 int walker_fetch(struct walker *walker, int targets, char **target,
255                  const char **write_ref, const char *write_ref_log_details)
256 {
257         struct strbuf refname = STRBUF_INIT;
258         struct strbuf err = STRBUF_INIT;
259         struct ref_transaction *transaction = NULL;
260         struct object_id *oids = xmalloc(targets * sizeof(struct object_id));
261         char *msg = NULL;
262         int i, ret = -1;
263
264         save_commit_buffer = 0;
265
266         if (write_ref) {
267                 transaction = ref_transaction_begin(&err);
268                 if (!transaction) {
269                         error("%s", err.buf);
270                         goto done;
271                 }
272         }
273
274         if (!walker->get_recover) {
275                 for_each_ref(mark_complete, NULL);
276                 commit_list_sort_by_date(&complete);
277         }
278
279         for (i = 0; i < targets; i++) {
280                 if (interpret_target(walker, target[i], oids + i)) {
281                         error("Could not interpret response from server '%s' as something to pull", target[i]);
282                         goto done;
283                 }
284                 if (process(walker, lookup_unknown_object(oids[i].hash)))
285                         goto done;
286         }
287
288         if (loop(walker))
289                 goto done;
290         if (!write_ref) {
291                 ret = 0;
292                 goto done;
293         }
294         if (write_ref_log_details) {
295                 msg = xstrfmt("fetch from %s", write_ref_log_details);
296         } else {
297                 msg = NULL;
298         }
299         for (i = 0; i < targets; i++) {
300                 if (!write_ref[i])
301                         continue;
302                 strbuf_reset(&refname);
303                 strbuf_addf(&refname, "refs/%s", write_ref[i]);
304                 if (ref_transaction_update(transaction, refname.buf,
305                                            oids + i, NULL, 0,
306                                            msg ? msg : "fetch (unknown)",
307                                            &err)) {
308                         error("%s", err.buf);
309                         goto done;
310                 }
311         }
312         if (ref_transaction_commit(transaction, &err)) {
313                 error("%s", err.buf);
314                 goto done;
315         }
316
317         ret = 0;
318
319 done:
320         ref_transaction_free(transaction);
321         free(msg);
322         free(oids);
323         strbuf_release(&err);
324         strbuf_release(&refname);
325         return ret;
326 }
327
328 void walker_free(struct walker *walker)
329 {
330         walker->cleanup(walker);
331         free(walker);
332 }