Merge branch 'nd/diff-flush-before-warning' into maint
[git] / walker.c
1 #include "cache.h"
2 #include "walker.h"
3 #include "commit.h"
4 #include "tree.h"
5 #include "tree-walk.h"
6 #include "tag.h"
7 #include "blob.h"
8 #include "refs.h"
9
10 static struct object_id current_commit_oid;
11
12 void walker_say(struct walker *walker, const char *fmt, ...)
13 {
14         if (walker->get_verbosely) {
15                 va_list ap;
16                 va_start(ap, fmt);
17                 vfprintf(stderr, fmt, ap);
18                 va_end(ap);
19         }
20 }
21
22 static void report_missing(const struct object *obj)
23 {
24         fprintf(stderr, "Cannot obtain needed %s %s\n",
25                 obj->type ? typename(obj->type): "object",
26                 oid_to_hex(&obj->oid));
27         if (!is_null_oid(&current_commit_oid))
28                 fprintf(stderr, "while processing commit %s.\n",
29                         oid_to_hex(&current_commit_oid));
30 }
31
32 static int process(struct walker *walker, struct object *obj);
33
34 static int process_tree(struct walker *walker, struct tree *tree)
35 {
36         struct tree_desc desc;
37         struct name_entry entry;
38
39         if (parse_tree(tree))
40                 return -1;
41
42         init_tree_desc(&desc, tree->buffer, tree->size);
43         while (tree_entry(&desc, &entry)) {
44                 struct object *obj = NULL;
45
46                 /* submodule commits are not stored in the superproject */
47                 if (S_ISGITLINK(entry.mode))
48                         continue;
49                 if (S_ISDIR(entry.mode)) {
50                         struct tree *tree = lookup_tree(entry.oid);
51                         if (tree)
52                                 obj = &tree->object;
53                 }
54                 else {
55                         struct blob *blob = lookup_blob(entry.oid);
56                         if (blob)
57                                 obj = &blob->object;
58                 }
59                 if (!obj || process(walker, obj))
60                         return -1;
61         }
62         free_tree_buffer(tree);
63         return 0;
64 }
65
66 /* Remember to update object flag allocation in object.h */
67 #define COMPLETE        (1U << 0)
68 #define SEEN            (1U << 1)
69 #define TO_SCAN         (1U << 2)
70
71 static struct commit_list *complete = NULL;
72
73 static int process_commit(struct walker *walker, struct commit *commit)
74 {
75         if (parse_commit(commit))
76                 return -1;
77
78         while (complete && complete->item->date >= commit->date) {
79                 pop_most_recent_commit(&complete, COMPLETE);
80         }
81
82         if (commit->object.flags & COMPLETE)
83                 return 0;
84
85         oidcpy(&current_commit_oid, &commit->object.oid);
86
87         walker_say(walker, "walk %s\n", oid_to_hex(&commit->object.oid));
88
89         if (walker->get_tree) {
90                 if (process(walker, &commit->tree->object))
91                         return -1;
92                 if (!walker->get_all)
93                         walker->get_tree = 0;
94         }
95         if (walker->get_history) {
96                 struct commit_list *parents = commit->parents;
97                 for (; parents; parents = parents->next) {
98                         if (process(walker, &parents->item->object))
99                                 return -1;
100                 }
101         }
102         return 0;
103 }
104
105 static int process_tag(struct walker *walker, struct tag *tag)
106 {
107         if (parse_tag(tag))
108                 return -1;
109         return process(walker, tag->tagged);
110 }
111
112 static struct object_list *process_queue = NULL;
113 static struct object_list **process_queue_end = &process_queue;
114
115 static int process_object(struct walker *walker, struct object *obj)
116 {
117         if (obj->type == OBJ_COMMIT) {
118                 if (process_commit(walker, (struct commit *)obj))
119                         return -1;
120                 return 0;
121         }
122         if (obj->type == OBJ_TREE) {
123                 if (process_tree(walker, (struct tree *)obj))
124                         return -1;
125                 return 0;
126         }
127         if (obj->type == OBJ_BLOB) {
128                 return 0;
129         }
130         if (obj->type == OBJ_TAG) {
131                 if (process_tag(walker, (struct tag *)obj))
132                         return -1;
133                 return 0;
134         }
135         return error("Unable to determine requirements "
136                      "of type %s for %s",
137                      typename(obj->type), oid_to_hex(&obj->oid));
138 }
139
140 static int process(struct walker *walker, struct object *obj)
141 {
142         if (obj->flags & SEEN)
143                 return 0;
144         obj->flags |= SEEN;
145
146         if (has_object_file(&obj->oid)) {
147                 /* We already have it, so we should scan it now. */
148                 obj->flags |= TO_SCAN;
149         }
150         else {
151                 if (obj->flags & COMPLETE)
152                         return 0;
153                 walker->prefetch(walker, obj->oid.hash);
154         }
155
156         object_list_insert(obj, process_queue_end);
157         process_queue_end = &(*process_queue_end)->next;
158         return 0;
159 }
160
161 static int loop(struct walker *walker)
162 {
163         struct object_list *elem;
164
165         while (process_queue) {
166                 struct object *obj = process_queue->item;
167                 elem = process_queue;
168                 process_queue = elem->next;
169                 free(elem);
170                 if (!process_queue)
171                         process_queue_end = &process_queue;
172
173                 /* If we are not scanning this object, we placed it in
174                  * the queue because we needed to fetch it first.
175                  */
176                 if (! (obj->flags & TO_SCAN)) {
177                         if (walker->fetch(walker, obj->oid.hash)) {
178                                 report_missing(obj);
179                                 return -1;
180                         }
181                 }
182                 if (!obj->type)
183                         parse_object(&obj->oid);
184                 if (process_object(walker, obj))
185                         return -1;
186         }
187         return 0;
188 }
189
190 static int interpret_target(struct walker *walker, char *target, struct object_id *oid)
191 {
192         if (!get_oid_hex(target, oid))
193                 return 0;
194         if (!check_refname_format(target, 0)) {
195                 struct ref *ref = alloc_ref(target);
196                 if (!walker->fetch_ref(walker, ref)) {
197                         oidcpy(oid, &ref->old_oid);
198                         free(ref);
199                         return 0;
200                 }
201                 free(ref);
202         }
203         return -1;
204 }
205
206 static int mark_complete(const char *path, const struct object_id *oid,
207                          int flag, void *cb_data)
208 {
209         struct commit *commit = lookup_commit_reference_gently(oid, 1);
210
211         if (commit) {
212                 commit->object.flags |= COMPLETE;
213                 commit_list_insert(commit, &complete);
214         }
215         return 0;
216 }
217
218 int walker_targets_stdin(char ***target, const char ***write_ref)
219 {
220         int targets = 0, targets_alloc = 0;
221         struct strbuf buf = STRBUF_INIT;
222         *target = NULL; *write_ref = NULL;
223         while (1) {
224                 char *rf_one = NULL;
225                 char *tg_one;
226
227                 if (strbuf_getline_lf(&buf, stdin) == EOF)
228                         break;
229                 tg_one = buf.buf;
230                 rf_one = strchr(tg_one, '\t');
231                 if (rf_one)
232                         *rf_one++ = 0;
233
234                 if (targets >= targets_alloc) {
235                         targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
236                         REALLOC_ARRAY(*target, targets_alloc);
237                         REALLOC_ARRAY(*write_ref, targets_alloc);
238                 }
239                 (*target)[targets] = xstrdup(tg_one);
240                 (*write_ref)[targets] = xstrdup_or_null(rf_one);
241                 targets++;
242         }
243         strbuf_release(&buf);
244         return targets;
245 }
246
247 void walker_targets_free(int targets, char **target, const char **write_ref)
248 {
249         while (targets--) {
250                 free(target[targets]);
251                 if (write_ref)
252                         free((char *) write_ref[targets]);
253         }
254 }
255
256 int walker_fetch(struct walker *walker, int targets, char **target,
257                  const char **write_ref, const char *write_ref_log_details)
258 {
259         struct strbuf refname = STRBUF_INIT;
260         struct strbuf err = STRBUF_INIT;
261         struct ref_transaction *transaction = NULL;
262         struct object_id *oids = xmalloc(targets * sizeof(struct object_id));
263         char *msg = NULL;
264         int i, ret = -1;
265
266         save_commit_buffer = 0;
267
268         if (write_ref) {
269                 transaction = ref_transaction_begin(&err);
270                 if (!transaction) {
271                         error("%s", err.buf);
272                         goto done;
273                 }
274         }
275
276         if (!walker->get_recover) {
277                 for_each_ref(mark_complete, NULL);
278                 commit_list_sort_by_date(&complete);
279         }
280
281         for (i = 0; i < targets; i++) {
282                 if (interpret_target(walker, target[i], oids + i)) {
283                         error("Could not interpret response from server '%s' as something to pull", target[i]);
284                         goto done;
285                 }
286                 if (process(walker, lookup_unknown_object(oids[i].hash)))
287                         goto done;
288         }
289
290         if (loop(walker))
291                 goto done;
292         if (!write_ref) {
293                 ret = 0;
294                 goto done;
295         }
296         if (write_ref_log_details) {
297                 msg = xstrfmt("fetch from %s", write_ref_log_details);
298         } else {
299                 msg = NULL;
300         }
301         for (i = 0; i < targets; i++) {
302                 if (!write_ref[i])
303                         continue;
304                 strbuf_reset(&refname);
305                 strbuf_addf(&refname, "refs/%s", write_ref[i]);
306                 if (ref_transaction_update(transaction, refname.buf,
307                                            oids + i, NULL, 0,
308                                            msg ? msg : "fetch (unknown)",
309                                            &err)) {
310                         error("%s", err.buf);
311                         goto done;
312                 }
313         }
314         if (ref_transaction_commit(transaction, &err)) {
315                 error("%s", err.buf);
316                 goto done;
317         }
318
319         ret = 0;
320
321 done:
322         ref_transaction_free(transaction);
323         free(msg);
324         free(oids);
325         strbuf_release(&err);
326         strbuf_release(&refname);
327         return ret;
328 }
329
330 void walker_free(struct walker *walker)
331 {
332         walker->cleanup(walker);
333         free(walker);
334 }