Merge branch 'maint'
[git] / bundle.c
1 #include "cache.h"
2 #include "bundle.h"
3 #include "object.h"
4 #include "commit.h"
5 #include "diff.h"
6 #include "revision.h"
7 #include "list-objects.h"
8 #include "run-command.h"
9
10 static const char bundle_signature[] = "# v2 git bundle\n";
11
12 static void add_to_ref_list(const unsigned char *sha1, const char *name,
13                 struct ref_list *list)
14 {
15         if (list->nr + 1 >= list->alloc) {
16                 list->alloc = alloc_nr(list->nr + 1);
17                 list->list = xrealloc(list->list,
18                                 list->alloc * sizeof(list->list[0]));
19         }
20         memcpy(list->list[list->nr].sha1, sha1, 20);
21         list->list[list->nr].name = xstrdup(name);
22         list->nr++;
23 }
24
25 /* returns an fd */
26 int read_bundle_header(const char *path, struct bundle_header *header) {
27         char buffer[1024];
28         int fd;
29         long fpos;
30         FILE *ffd = fopen(path, "rb");
31
32         if (!ffd)
33                 return error("could not open '%s'", path);
34         if (!fgets(buffer, sizeof(buffer), ffd) ||
35                         strcmp(buffer, bundle_signature)) {
36                 fclose(ffd);
37                 return error("'%s' does not look like a v2 bundle file", path);
38         }
39         while (fgets(buffer, sizeof(buffer), ffd)
40                         && buffer[0] != '\n') {
41                 int is_prereq = buffer[0] == '-';
42                 int offset = is_prereq ? 1 : 0;
43                 int len = strlen(buffer);
44                 unsigned char sha1[20];
45                 struct ref_list *list = is_prereq ? &header->prerequisites
46                         : &header->references;
47                 char delim;
48
49                 if (buffer[len - 1] == '\n')
50                         buffer[len - 1] = '\0';
51                 if (get_sha1_hex(buffer + offset, sha1)) {
52                         warning("unrecognized header: %s", buffer);
53                         continue;
54                 }
55                 delim = buffer[40 + offset];
56                 if (!isspace(delim) && (delim != '\0' || !is_prereq))
57                         die ("invalid header: %s", buffer);
58                 add_to_ref_list(sha1, isspace(delim) ?
59                                 buffer + 41 + offset : "", list);
60         }
61         fpos = ftell(ffd);
62         fclose(ffd);
63         fd = open(path, O_RDONLY);
64         if (fd < 0)
65                 return error("could not open '%s'", path);
66         lseek(fd, fpos, SEEK_SET);
67         return fd;
68 }
69
70 static int list_refs(struct ref_list *r, int argc, const char **argv)
71 {
72         int i;
73
74         for (i = 0; i < r->nr; i++) {
75                 if (argc > 1) {
76                         int j;
77                         for (j = 1; j < argc; j++)
78                                 if (!strcmp(r->list[i].name, argv[j]))
79                                         break;
80                         if (j == argc)
81                                 continue;
82                 }
83                 printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
84                                 r->list[i].name);
85         }
86         return 0;
87 }
88
89 #define PREREQ_MARK (1u<<16)
90
91 int verify_bundle(struct bundle_header *header, int verbose)
92 {
93         /*
94          * Do fast check, then if any prereqs are missing then go line by line
95          * to be verbose about the errors
96          */
97         struct ref_list *p = &header->prerequisites;
98         struct rev_info revs;
99         const char *argv[] = {NULL, "--all"};
100         struct object_array refs;
101         struct commit *commit;
102         int i, ret = 0, req_nr;
103         const char *message = "Repository lacks these prerequisite commits:";
104
105         init_revisions(&revs, NULL);
106         for (i = 0; i < p->nr; i++) {
107                 struct ref_list_entry *e = p->list + i;
108                 struct object *o = parse_object(e->sha1);
109                 if (o) {
110                         o->flags |= PREREQ_MARK;
111                         add_pending_object(&revs, o, e->name);
112                         continue;
113                 }
114                 if (++ret == 1)
115                         error(message);
116                 error("%s %s", sha1_to_hex(e->sha1), e->name);
117         }
118         if (revs.pending.nr != p->nr)
119                 return ret;
120         req_nr = revs.pending.nr;
121         setup_revisions(2, argv, &revs, NULL);
122
123         memset(&refs, 0, sizeof(struct object_array));
124         for (i = 0; i < revs.pending.nr; i++) {
125                 struct object_array_entry *e = revs.pending.objects + i;
126                 add_object_array(e->item, e->name, &refs);
127         }
128
129         prepare_revision_walk(&revs);
130
131         i = req_nr;
132         while (i && (commit = get_revision(&revs)))
133                 if (commit->object.flags & PREREQ_MARK)
134                         i--;
135
136         for (i = 0; i < req_nr; i++)
137                 if (!(refs.objects[i].item->flags & SHOWN)) {
138                         if (++ret == 1)
139                                 error(message);
140                         error("%s %s", sha1_to_hex(refs.objects[i].item->sha1),
141                                 refs.objects[i].name);
142                 }
143
144         for (i = 0; i < refs.nr; i++)
145                 clear_commit_marks((struct commit *)refs.objects[i].item, -1);
146
147         if (verbose) {
148                 struct ref_list *r;
149
150                 r = &header->references;
151                 printf("The bundle contains %d ref%s\n",
152                        r->nr, (1 < r->nr) ? "s" : "");
153                 list_refs(r, 0, NULL);
154                 r = &header->prerequisites;
155                 printf("The bundle requires these %d ref%s\n",
156                        r->nr, (1 < r->nr) ? "s" : "");
157                 list_refs(r, 0, NULL);
158         }
159         return ret;
160 }
161
162 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
163 {
164         return list_refs(&header->references, argc, argv);
165 }
166
167 int create_bundle(struct bundle_header *header, const char *path,
168                 int argc, const char **argv)
169 {
170         static struct lock_file lock;
171         int bundle_fd = -1;
172         int bundle_to_stdout;
173         const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
174         const char **argv_pack = xmalloc(5 * sizeof(const char *));
175         int i, ref_count = 0;
176         char buffer[1024];
177         struct rev_info revs;
178         struct child_process rls;
179         FILE *rls_fout;
180
181         bundle_to_stdout = !strcmp(path, "-");
182         if (bundle_to_stdout)
183                 bundle_fd = 1;
184         else
185                 bundle_fd = hold_lock_file_for_update(&lock, path, 1);
186
187         /* write signature */
188         write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
189
190         /* init revs to list objects for pack-objects later */
191         save_commit_buffer = 0;
192         init_revisions(&revs, NULL);
193
194         /* write prerequisites */
195         memcpy(argv_boundary + 3, argv + 1, argc * sizeof(const char *));
196         argv_boundary[0] = "rev-list";
197         argv_boundary[1] = "--boundary";
198         argv_boundary[2] = "--pretty=oneline";
199         argv_boundary[argc + 2] = NULL;
200         memset(&rls, 0, sizeof(rls));
201         rls.argv = argv_boundary;
202         rls.out = -1;
203         rls.git_cmd = 1;
204         if (start_command(&rls))
205                 return -1;
206         rls_fout = fdopen(rls.out, "r");
207         while (fgets(buffer, sizeof(buffer), rls_fout)) {
208                 unsigned char sha1[20];
209                 if (buffer[0] == '-') {
210                         write_or_die(bundle_fd, buffer, strlen(buffer));
211                         if (!get_sha1_hex(buffer + 1, sha1)) {
212                                 struct object *object = parse_object(sha1);
213                                 object->flags |= UNINTERESTING;
214                                 add_pending_object(&revs, object, buffer);
215                         }
216                 } else if (!get_sha1_hex(buffer, sha1)) {
217                         struct object *object = parse_object(sha1);
218                         object->flags |= SHOWN;
219                 }
220         }
221         fclose(rls_fout);
222         if (finish_command(&rls))
223                 return error("rev-list died");
224
225         /* write references */
226         argc = setup_revisions(argc, argv, &revs, NULL);
227         if (argc > 1)
228                 return error("unrecognized argument: %s'", argv[1]);
229
230         for (i = 0; i < revs.pending.nr; i++) {
231                 struct object_array_entry *e = revs.pending.objects + i;
232                 unsigned char sha1[20];
233                 char *ref;
234
235                 if (e->item->flags & UNINTERESTING)
236                         continue;
237                 if (dwim_ref(e->name, strlen(e->name), sha1, &ref) != 1)
238                         continue;
239                 /*
240                  * Make sure the refs we wrote out is correct; --max-count and
241                  * other limiting options could have prevented all the tips
242                  * from getting output.
243                  *
244                  * Non commit objects such as tags and blobs do not have
245                  * this issue as they are not affected by those extra
246                  * constraints.
247                  */
248                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
249                         warning("ref '%s' is excluded by the rev-list options",
250                                 e->name);
251                         free(ref);
252                         continue;
253                 }
254                 /*
255                  * If you run "git bundle create bndl v1.0..v2.0", the
256                  * name of the positive ref is "v2.0" but that is the
257                  * commit that is referenced by the tag, and not the tag
258                  * itself.
259                  */
260                 if (hashcmp(sha1, e->item->sha1)) {
261                         /*
262                          * Is this the positive end of a range expressed
263                          * in terms of a tag (e.g. v2.0 from the range
264                          * "v1.0..v2.0")?
265                          */
266                         struct commit *one = lookup_commit_reference(sha1);
267                         struct object *obj;
268
269                         if (e->item == &(one->object)) {
270                                 /*
271                                  * Need to include e->name as an
272                                  * independent ref to the pack-objects
273                                  * input, so that the tag is included
274                                  * in the output; otherwise we would
275                                  * end up triggering "empty bundle"
276                                  * error.
277                                  */
278                                 obj = parse_object(sha1);
279                                 obj->flags |= SHOWN;
280                                 add_pending_object(&revs, obj, e->name);
281                         }
282                         free(ref);
283                         continue;
284                 }
285
286                 ref_count++;
287                 write_or_die(bundle_fd, sha1_to_hex(e->item->sha1), 40);
288                 write_or_die(bundle_fd, " ", 1);
289                 write_or_die(bundle_fd, ref, strlen(ref));
290                 write_or_die(bundle_fd, "\n", 1);
291                 free(ref);
292         }
293         if (!ref_count)
294                 die ("Refusing to create empty bundle.");
295
296         /* end header */
297         write_or_die(bundle_fd, "\n", 1);
298
299         /* write pack */
300         argv_pack[0] = "pack-objects";
301         argv_pack[1] = "--all-progress";
302         argv_pack[2] = "--stdout";
303         argv_pack[3] = "--thin";
304         argv_pack[4] = NULL;
305         memset(&rls, 0, sizeof(rls));
306         rls.argv = argv_pack;
307         rls.in = -1;
308         rls.out = bundle_fd;
309         rls.git_cmd = 1;
310         if (start_command(&rls))
311                 return error("Could not spawn pack-objects");
312         for (i = 0; i < revs.pending.nr; i++) {
313                 struct object *object = revs.pending.objects[i].item;
314                 if (object->flags & UNINTERESTING)
315                         write(rls.in, "^", 1);
316                 write(rls.in, sha1_to_hex(object->sha1), 40);
317                 write(rls.in, "\n", 1);
318         }
319         if (finish_command(&rls))
320                 return error ("pack-objects died");
321         close(bundle_fd);
322         if (!bundle_to_stdout)
323                 commit_lock_file(&lock);
324         return 0;
325 }
326
327 int unbundle(struct bundle_header *header, int bundle_fd)
328 {
329         const char *argv_index_pack[] = {"index-pack",
330                 "--fix-thin", "--stdin", NULL};
331         struct child_process ip;
332
333         if (verify_bundle(header, 0))
334                 return -1;
335         memset(&ip, 0, sizeof(ip));
336         ip.argv = argv_index_pack;
337         ip.in = bundle_fd;
338         ip.no_stdout = 1;
339         ip.git_cmd = 1;
340         if (run_command(&ip))
341                 return error("index-pack died");
342         return 0;
343 }