Code

tutorial: revise index introduction
[git.git] / fetch.c
1 #include "cache.h"
2 #include "fetch.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 #include "strbuf.h"
11 int get_tree = 0;
12 int get_history = 0;
13 int get_all = 0;
14 int get_verbosely = 0;
15 int get_recover = 0;
16 static unsigned char current_commit_sha1[20];
18 void pull_say(const char *fmt, const char *hex) 
19 {
20         if (get_verbosely)
21                 fprintf(stderr, fmt, hex);
22 }
24 static void report_missing(const struct object *obj)
25 {
26         char missing_hex[41];
27         strcpy(missing_hex, sha1_to_hex(obj->sha1));;
28         fprintf(stderr, "Cannot obtain needed %s %s\n",
29                 obj->type ? typename(obj->type): "object", missing_hex);
30         if (!is_null_sha1(current_commit_sha1))
31                 fprintf(stderr, "while processing commit %s.\n",
32                         sha1_to_hex(current_commit_sha1));
33 }
35 static int process(struct object *obj);
37 static int process_tree(struct tree *tree)
38 {
39         struct tree_desc desc;
40         struct name_entry entry;
42         if (parse_tree(tree))
43                 return -1;
45         init_tree_desc(&desc, tree->buffer, tree->size);
46         while (tree_entry(&desc, &entry)) {
47                 struct object *obj = NULL;
49                 if (S_ISDIR(entry.mode)) {
50                         struct tree *tree = lookup_tree(entry.sha1);
51                         if (tree)
52                                 obj = &tree->object;
53                 }
54                 else {
55                         struct blob *blob = lookup_blob(entry.sha1);
56                         if (blob)
57                                 obj = &blob->object;
58                 }
59                 if (!obj || process(obj))
60                         return -1;
61         }
62         free(tree->buffer);
63         tree->buffer = NULL;
64         tree->size = 0;
65         return 0;
66 }
68 #define COMPLETE        (1U << 0)
69 #define SEEN            (1U << 1)
70 #define TO_SCAN         (1U << 2)
72 static struct commit_list *complete = NULL;
74 static int process_commit(struct commit *commit)
75 {
76         if (parse_commit(commit))
77                 return -1;
79         while (complete && complete->item->date >= commit->date) {
80                 pop_most_recent_commit(&complete, COMPLETE);
81         }
83         if (commit->object.flags & COMPLETE)
84                 return 0;
86         hashcpy(current_commit_sha1, commit->object.sha1);
88         pull_say("walk %s\n", sha1_to_hex(commit->object.sha1));
90         if (get_tree) {
91                 if (process(&commit->tree->object))
92                         return -1;
93                 if (!get_all)
94                         get_tree = 0;
95         }
96         if (get_history) {
97                 struct commit_list *parents = commit->parents;
98                 for (; parents; parents = parents->next) {
99                         if (process(&parents->item->object))
100                                 return -1;
101                 }
102         }
103         return 0;
106 static int process_tag(struct tag *tag)
108         if (parse_tag(tag))
109                 return -1;
110         return process(tag->tagged);
113 static struct object_list *process_queue = NULL;
114 static struct object_list **process_queue_end = &process_queue;
116 static int process_object(struct object *obj)
118         if (obj->type == OBJ_COMMIT) {
119                 if (process_commit((struct commit *)obj))
120                         return -1;
121                 return 0;
122         }
123         if (obj->type == OBJ_TREE) {
124                 if (process_tree((struct tree *)obj))
125                         return -1;
126                 return 0;
127         }
128         if (obj->type == OBJ_BLOB) {
129                 return 0;
130         }
131         if (obj->type == OBJ_TAG) {
132                 if (process_tag((struct tag *)obj))
133                         return -1;
134                 return 0;
135         }
136         return error("Unable to determine requirements "
137                      "of type %s for %s",
138                      typename(obj->type), sha1_to_hex(obj->sha1));
141 static int process(struct object *obj)
143         if (obj->flags & SEEN)
144                 return 0;
145         obj->flags |= SEEN;
147         if (has_sha1_file(obj->sha1)) {
148                 /* We already have it, so we should scan it now. */
149                 obj->flags |= TO_SCAN;
150         }
151         else {
152                 if (obj->flags & COMPLETE)
153                         return 0;
154                 prefetch(obj->sha1);
155         }
156                 
157         object_list_insert(obj, process_queue_end);
158         process_queue_end = &(*process_queue_end)->next;
159         return 0;
162 static int loop(void)
164         struct object_list *elem;
166         while (process_queue) {
167                 struct object *obj = process_queue->item;
168                 elem = process_queue;
169                 process_queue = elem->next;
170                 free(elem);
171                 if (!process_queue)
172                         process_queue_end = &process_queue;
174                 /* If we are not scanning this object, we placed it in
175                  * the queue because we needed to fetch it first.
176                  */
177                 if (! (obj->flags & TO_SCAN)) {
178                         if (fetch(obj->sha1)) {
179                                 report_missing(obj);
180                                 return -1;
181                         }
182                 }
183                 if (!obj->type)
184                         parse_object(obj->sha1);
185                 if (process_object(obj))
186                         return -1;
187         }
188         return 0;
191 static int interpret_target(char *target, unsigned char *sha1)
193         if (!get_sha1_hex(target, sha1))
194                 return 0;
195         if (!check_ref_format(target)) {
196                 if (!fetch_ref(target, sha1)) {
197                         return 0;
198                 }
199         }
200         return -1;
203 static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data)
205         struct commit *commit = lookup_commit_reference_gently(sha1, 1);
206         if (commit) {
207                 commit->object.flags |= COMPLETE;
208                 insert_by_date(commit, &complete);
209         }
210         return 0;
213 int pull_targets_stdin(char ***target, const char ***write_ref)
215         int targets = 0, targets_alloc = 0;
216         struct strbuf buf;
217         *target = NULL; *write_ref = NULL;
218         strbuf_init(&buf);
219         while (1) {
220                 char *rf_one = NULL;
221                 char *tg_one;
223                 read_line(&buf, stdin, '\n');
224                 if (buf.eof)
225                         break;
226                 tg_one = buf.buf;
227                 rf_one = strchr(tg_one, '\t');
228                 if (rf_one)
229                         *rf_one++ = 0;
231                 if (targets >= targets_alloc) {
232                         targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
233                         *target = xrealloc(*target, targets_alloc * sizeof(**target));
234                         *write_ref = xrealloc(*write_ref, targets_alloc * sizeof(**write_ref));
235                 }
236                 (*target)[targets] = xstrdup(tg_one);
237                 (*write_ref)[targets] = rf_one ? xstrdup(rf_one) : NULL;
238                 targets++;
239         }
240         return targets;
243 void pull_targets_free(int targets, char **target, const char **write_ref)
245         while (targets--) {
246                 free(target[targets]);
247                 if (write_ref && write_ref[targets])
248                         free((char *) write_ref[targets]);
249         }
252 int pull(int targets, char **target, const char **write_ref,
253          const char *write_ref_log_details)
255         struct ref_lock **lock = xcalloc(targets, sizeof(struct ref_lock *));
256         unsigned char *sha1 = xmalloc(targets * 20);
257         char *msg;
258         int ret;
259         int i;
261         save_commit_buffer = 0;
262         track_object_refs = 0;
264         for (i = 0; i < targets; i++) {
265                 if (!write_ref || !write_ref[i])
266                         continue;
268                 lock[i] = lock_ref_sha1(write_ref[i], NULL);
269                 if (!lock[i]) {
270                         error("Can't lock ref %s", write_ref[i]);
271                         goto unlock_and_fail;
272                 }
273         }
275         if (!get_recover)
276                 for_each_ref(mark_complete, NULL);
278         for (i = 0; i < targets; i++) {
279                 if (interpret_target(target[i], &sha1[20 * i])) {
280                         error("Could not interpret %s as something to pull", target[i]);
281                         goto unlock_and_fail;
282                 }
283                 if (process(lookup_unknown_object(&sha1[20 * i])))
284                         goto unlock_and_fail;
285         }
287         if (loop())
288                 goto unlock_and_fail;
290         if (write_ref_log_details) {
291                 msg = xmalloc(strlen(write_ref_log_details) + 12);
292                 sprintf(msg, "fetch from %s", write_ref_log_details);
293         } else {
294                 msg = NULL;
295         }
296         for (i = 0; i < targets; i++) {
297                 if (!write_ref || !write_ref[i])
298                         continue;
299                 ret = write_ref_sha1(lock[i], &sha1[20 * i], msg ? msg : "fetch (unknown)");
300                 lock[i] = NULL;
301                 if (ret)
302                         goto unlock_and_fail;
303         }
304         free(msg);
306         return 0;
309 unlock_and_fail:
310         for (i = 0; i < targets; i++)
311                 if (lock[i])
312                         unlock_ref(lock[i]);
313         return -1;