Merge branch 'py/diff-submodule'
[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 #include "refs.h"
10
11 static const char bundle_signature[] = "# v2 git bundle\n";
12
13 static void add_to_ref_list(const unsigned char *sha1, const char *name,
14                 struct ref_list *list)
15 {
16         if (list->nr + 1 >= list->alloc) {
17                 list->alloc = alloc_nr(list->nr + 1);
18                 list->list = xrealloc(list->list,
19                                 list->alloc * sizeof(list->list[0]));
20         }
21         memcpy(list->list[list->nr].sha1, sha1, 20);
22         list->list[list->nr].name = xstrdup(name);
23         list->nr++;
24 }
25
26 /* returns an fd */
27 int read_bundle_header(const char *path, struct bundle_header *header)
28 {
29         char buffer[1024];
30         int fd;
31         long fpos;
32         FILE *ffd = fopen(path, "rb");
33
34         if (!ffd)
35                 return error("could not open '%s'", path);
36         if (!fgets(buffer, sizeof(buffer), ffd) ||
37                         strcmp(buffer, bundle_signature)) {
38                 fclose(ffd);
39                 return error("'%s' does not look like a v2 bundle file", path);
40         }
41         while (fgets(buffer, sizeof(buffer), ffd)
42                         && buffer[0] != '\n') {
43                 int is_prereq = buffer[0] == '-';
44                 int offset = is_prereq ? 1 : 0;
45                 int len = strlen(buffer);
46                 unsigned char sha1[20];
47                 struct ref_list *list = is_prereq ? &header->prerequisites
48                         : &header->references;
49                 char delim;
50
51                 if (len && buffer[len - 1] == '\n')
52                         buffer[len - 1] = '\0';
53                 if (get_sha1_hex(buffer + offset, sha1)) {
54                         warning("unrecognized header: %s", buffer);
55                         continue;
56                 }
57                 delim = buffer[40 + offset];
58                 if (!isspace(delim) && (delim != '\0' || !is_prereq))
59                         die ("invalid header: %s", buffer);
60                 add_to_ref_list(sha1, isspace(delim) ?
61                                 buffer + 41 + offset : "", list);
62         }
63         fpos = ftell(ffd);
64         fclose(ffd);
65         fd = open(path, O_RDONLY);
66         if (fd < 0)
67                 return error("could not open '%s'", path);
68         lseek(fd, fpos, SEEK_SET);
69         return fd;
70 }
71
72 static int list_refs(struct ref_list *r, int argc, const char **argv)
73 {
74         int i;
75
76         for (i = 0; i < r->nr; i++) {
77                 if (argc > 1) {
78                         int j;
79                         for (j = 1; j < argc; j++)
80                                 if (!strcmp(r->list[i].name, argv[j]))
81                                         break;
82                         if (j == argc)
83                                 continue;
84                 }
85                 printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
86                                 r->list[i].name);
87         }
88         return 0;
89 }
90
91 #define PREREQ_MARK (1u<<16)
92
93 int verify_bundle(struct bundle_header *header, int verbose)
94 {
95         /*
96          * Do fast check, then if any prereqs are missing then go line by line
97          * to be verbose about the errors
98          */
99         struct ref_list *p = &header->prerequisites;
100         struct rev_info revs;
101         const char *argv[] = {NULL, "--all"};
102         struct object_array refs;
103         struct commit *commit;
104         int i, ret = 0, req_nr;
105         const char *message = "Repository lacks these prerequisite commits:";
106
107         init_revisions(&revs, NULL);
108         for (i = 0; i < p->nr; i++) {
109                 struct ref_list_entry *e = p->list + i;
110                 struct object *o = parse_object(e->sha1);
111                 if (o) {
112                         o->flags |= PREREQ_MARK;
113                         add_pending_object(&revs, o, e->name);
114                         continue;
115                 }
116                 if (++ret == 1)
117                         error(message);
118                 error("%s %s", sha1_to_hex(e->sha1), e->name);
119         }
120         if (revs.pending.nr != p->nr)
121                 return ret;
122         req_nr = revs.pending.nr;
123         setup_revisions(2, argv, &revs, NULL);
124
125         memset(&refs, 0, sizeof(struct object_array));
126         for (i = 0; i < revs.pending.nr; i++) {
127                 struct object_array_entry *e = revs.pending.objects + i;
128                 add_object_array(e->item, e->name, &refs);
129         }
130
131         if (prepare_revision_walk(&revs))
132                 die("revision walk setup failed");
133
134         i = req_nr;
135         while (i && (commit = get_revision(&revs)))
136                 if (commit->object.flags & PREREQ_MARK)
137                         i--;
138
139         for (i = 0; i < req_nr; i++)
140                 if (!(refs.objects[i].item->flags & SHOWN)) {
141                         if (++ret == 1)
142                                 error(message);
143                         error("%s %s", sha1_to_hex(refs.objects[i].item->sha1),
144                                 refs.objects[i].name);
145                 }
146
147         for (i = 0; i < refs.nr; i++)
148                 clear_commit_marks((struct commit *)refs.objects[i].item, -1);
149
150         if (verbose) {
151                 struct ref_list *r;
152
153                 r = &header->references;
154                 printf("The bundle contains %d ref%s\n",
155                        r->nr, (1 < r->nr) ? "s" : "");
156                 list_refs(r, 0, NULL);
157                 r = &header->prerequisites;
158                 printf("The bundle requires these %d ref%s\n",
159                        r->nr, (1 < r->nr) ? "s" : "");
160                 list_refs(r, 0, NULL);
161         }
162         return ret;
163 }
164
165 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
166 {
167         return list_refs(&header->references, argc, argv);
168 }
169
170 int create_bundle(struct bundle_header *header, const char *path,
171                 int argc, const char **argv)
172 {
173         static struct lock_file lock;
174         int bundle_fd = -1;
175         int bundle_to_stdout;
176         const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
177         const char **argv_pack = xmalloc(5 * sizeof(const char *));
178         int i, ref_count = 0;
179         char buffer[1024];
180         struct rev_info revs;
181         struct child_process rls;
182         FILE *rls_fout;
183
184         bundle_to_stdout = !strcmp(path, "-");
185         if (bundle_to_stdout)
186                 bundle_fd = 1;
187         else
188                 bundle_fd = hold_lock_file_for_update(&lock, path, 1);
189
190         /* write signature */
191         write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
192
193         /* init revs to list objects for pack-objects later */
194         save_commit_buffer = 0;
195         init_revisions(&revs, NULL);
196
197         /* write prerequisites */
198         memcpy(argv_boundary + 3, argv + 1, argc * sizeof(const char *));
199         argv_boundary[0] = "rev-list";
200         argv_boundary[1] = "--boundary";
201         argv_boundary[2] = "--pretty=oneline";
202         argv_boundary[argc + 2] = NULL;
203         memset(&rls, 0, sizeof(rls));
204         rls.argv = argv_boundary;
205         rls.out = -1;
206         rls.git_cmd = 1;
207         if (start_command(&rls))
208                 return -1;
209         rls_fout = fdopen(rls.out, "r");
210         while (fgets(buffer, sizeof(buffer), rls_fout)) {
211                 unsigned char sha1[20];
212                 if (buffer[0] == '-') {
213                         write_or_die(bundle_fd, buffer, strlen(buffer));
214                         if (!get_sha1_hex(buffer + 1, sha1)) {
215                                 struct object *object = parse_object(sha1);
216                                 object->flags |= UNINTERESTING;
217                                 add_pending_object(&revs, object, buffer);
218                         }
219                 } else if (!get_sha1_hex(buffer, sha1)) {
220                         struct object *object = parse_object(sha1);
221                         object->flags |= SHOWN;
222                 }
223         }
224         fclose(rls_fout);
225         if (finish_command(&rls))
226                 return error("rev-list died");
227
228         /* write references */
229         argc = setup_revisions(argc, argv, &revs, NULL);
230         if (argc > 1)
231                 return error("unrecognized argument: %s'", argv[1]);
232
233         for (i = 0; i < revs.pending.nr; i++) {
234                 struct object_array_entry *e = revs.pending.objects + i;
235                 unsigned char sha1[20];
236                 char *ref;
237                 const char *display_ref;
238                 int flag;
239
240                 if (e->item->flags & UNINTERESTING)
241                         continue;
242                 if (dwim_ref(e->name, strlen(e->name), sha1, &ref) != 1)
243                         continue;
244                 if (!resolve_ref(e->name, sha1, 1, &flag))
245                         flag = 0;
246                 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
247
248                 /*
249                  * Make sure the refs we wrote out is correct; --max-count and
250                  * other limiting options could have prevented all the tips
251                  * from getting output.
252                  *
253                  * Non commit objects such as tags and blobs do not have
254                  * this issue as they are not affected by those extra
255                  * constraints.
256                  */
257                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
258                         warning("ref '%s' is excluded by the rev-list options",
259                                 e->name);
260                         free(ref);
261                         continue;
262                 }
263                 /*
264                  * If you run "git bundle create bndl v1.0..v2.0", the
265                  * name of the positive ref is "v2.0" but that is the
266                  * commit that is referenced by the tag, and not the tag
267                  * itself.
268                  */
269                 if (hashcmp(sha1, e->item->sha1)) {
270                         /*
271                          * Is this the positive end of a range expressed
272                          * in terms of a tag (e.g. v2.0 from the range
273                          * "v1.0..v2.0")?
274                          */
275                         struct commit *one = lookup_commit_reference(sha1);
276                         struct object *obj;
277
278                         if (e->item == &(one->object)) {
279                                 /*
280                                  * Need to include e->name as an
281                                  * independent ref to the pack-objects
282                                  * input, so that the tag is included
283                                  * in the output; otherwise we would
284                                  * end up triggering "empty bundle"
285                                  * error.
286                                  */
287                                 obj = parse_object(sha1);
288                                 obj->flags |= SHOWN;
289                                 add_pending_object(&revs, obj, e->name);
290                         }
291                         free(ref);
292                         continue;
293                 }
294
295                 ref_count++;
296                 write_or_die(bundle_fd, sha1_to_hex(e->item->sha1), 40);
297                 write_or_die(bundle_fd, " ", 1);
298                 write_or_die(bundle_fd, display_ref, strlen(display_ref));
299                 write_or_die(bundle_fd, "\n", 1);
300                 free(ref);
301         }
302         if (!ref_count)
303                 die ("Refusing to create empty bundle.");
304
305         /* end header */
306         write_or_die(bundle_fd, "\n", 1);
307
308         /* write pack */
309         argv_pack[0] = "pack-objects";
310         argv_pack[1] = "--all-progress";
311         argv_pack[2] = "--stdout";
312         argv_pack[3] = "--thin";
313         argv_pack[4] = NULL;
314         memset(&rls, 0, sizeof(rls));
315         rls.argv = argv_pack;
316         rls.in = -1;
317         rls.out = bundle_fd;
318         rls.git_cmd = 1;
319         if (start_command(&rls))
320                 return error("Could not spawn pack-objects");
321
322         /*
323          * start_command closed bundle_fd if it was > 1
324          * so set the lock fd to -1 so commit_lock_file()
325          * won't fail trying to close it.
326          */
327         lock.fd = -1;
328
329         for (i = 0; i < revs.pending.nr; i++) {
330                 struct object *object = revs.pending.objects[i].item;
331                 if (object->flags & UNINTERESTING)
332                         write_or_die(rls.in, "^", 1);
333                 write_or_die(rls.in, sha1_to_hex(object->sha1), 40);
334                 write_or_die(rls.in, "\n", 1);
335         }
336         close(rls.in);
337         if (finish_command(&rls))
338                 return error ("pack-objects died");
339         if (!bundle_to_stdout)
340                 commit_lock_file(&lock);
341         return 0;
342 }
343
344 int unbundle(struct bundle_header *header, int bundle_fd)
345 {
346         const char *argv_index_pack[] = {"index-pack",
347                 "--fix-thin", "--stdin", NULL};
348         struct child_process ip;
349
350         if (verify_bundle(header, 0))
351                 return -1;
352         memset(&ip, 0, sizeof(ip));
353         ip.argv = argv_index_pack;
354         ip.in = bundle_fd;
355         ip.no_stdout = 1;
356         ip.git_cmd = 1;
357         if (run_command(&ip))
358                 return error("index-pack died");
359         return 0;
360 }