wt-status: tolerate dangling marks
[git] / bundle.c
1 #include "cache.h"
2 #include "lockfile.h"
3 #include "bundle.h"
4 #include "object-store.h"
5 #include "repository.h"
6 #include "object.h"
7 #include "commit.h"
8 #include "diff.h"
9 #include "revision.h"
10 #include "list-objects.h"
11 #include "run-command.h"
12 #include "refs.h"
13 #include "argv-array.h"
14
15 static const char bundle_signature[] = "# v2 git bundle\n";
16
17 static void add_to_ref_list(const struct object_id *oid, const char *name,
18                 struct ref_list *list)
19 {
20         ALLOC_GROW(list->list, list->nr + 1, list->alloc);
21         oidcpy(&list->list[list->nr].oid, oid);
22         list->list[list->nr].name = xstrdup(name);
23         list->nr++;
24 }
25
26 static const struct git_hash_algo *detect_hash_algo(struct strbuf *buf)
27 {
28         size_t len = strcspn(buf->buf, " \n");
29         int algo;
30
31         algo = hash_algo_by_length(len / 2);
32         if (algo == GIT_HASH_UNKNOWN)
33                 return NULL;
34         return &hash_algos[algo];
35 }
36
37 static int parse_bundle_header(int fd, struct bundle_header *header,
38                                const char *report_path)
39 {
40         struct strbuf buf = STRBUF_INIT;
41         int status = 0;
42
43         /* The bundle header begins with the signature */
44         if (strbuf_getwholeline_fd(&buf, fd, '\n') ||
45             strcmp(buf.buf, bundle_signature)) {
46                 if (report_path)
47                         error(_("'%s' does not look like a v2 bundle file"),
48                               report_path);
49                 status = -1;
50                 goto abort;
51         }
52
53         /* The bundle header ends with an empty line */
54         while (!strbuf_getwholeline_fd(&buf, fd, '\n') &&
55                buf.len && buf.buf[0] != '\n') {
56                 struct object_id oid;
57                 int is_prereq = 0;
58                 const char *p;
59
60                 if (*buf.buf == '-') {
61                         is_prereq = 1;
62                         strbuf_remove(&buf, 0, 1);
63                 }
64                 strbuf_rtrim(&buf);
65
66                 if (!header->hash_algo) {
67                         header->hash_algo = detect_hash_algo(&buf);
68                         if (!header->hash_algo) {
69                                 error(_("unknown hash algorithm length"));
70                                 status = -1;
71                                 break;
72                         }
73                 }
74
75                 /*
76                  * Tip lines have object name, SP, and refname.
77                  * Prerequisites have object name that is optionally
78                  * followed by SP and subject line.
79                  */
80                 if (parse_oid_hex_algop(buf.buf, &oid, &p, header->hash_algo) ||
81                     (*p && !isspace(*p)) ||
82                     (!is_prereq && !*p)) {
83                         if (report_path)
84                                 error(_("unrecognized header: %s%s (%d)"),
85                                       (is_prereq ? "-" : ""), buf.buf, (int)buf.len);
86                         status = -1;
87                         break;
88                 } else {
89                         if (is_prereq)
90                                 add_to_ref_list(&oid, "", &header->prerequisites);
91                         else
92                                 add_to_ref_list(&oid, p + 1, &header->references);
93                 }
94         }
95
96  abort:
97         if (status) {
98                 close(fd);
99                 fd = -1;
100         }
101         strbuf_release(&buf);
102         return fd;
103 }
104
105 int read_bundle_header(const char *path, struct bundle_header *header)
106 {
107         int fd = open(path, O_RDONLY);
108
109         if (fd < 0)
110                 return error(_("could not open '%s'"), path);
111         return parse_bundle_header(fd, header, path);
112 }
113
114 int is_bundle(const char *path, int quiet)
115 {
116         struct bundle_header header;
117         int fd = open(path, O_RDONLY);
118
119         if (fd < 0)
120                 return 0;
121         memset(&header, 0, sizeof(header));
122         fd = parse_bundle_header(fd, &header, quiet ? NULL : path);
123         if (fd >= 0)
124                 close(fd);
125         return (fd >= 0);
126 }
127
128 static int list_refs(struct ref_list *r, int argc, const char **argv)
129 {
130         int i;
131
132         for (i = 0; i < r->nr; i++) {
133                 if (argc > 1) {
134                         int j;
135                         for (j = 1; j < argc; j++)
136                                 if (!strcmp(r->list[i].name, argv[j]))
137                                         break;
138                         if (j == argc)
139                                 continue;
140                 }
141                 printf("%s %s\n", oid_to_hex(&r->list[i].oid),
142                                 r->list[i].name);
143         }
144         return 0;
145 }
146
147 /* Remember to update object flag allocation in object.h */
148 #define PREREQ_MARK (1u<<16)
149
150 int verify_bundle(struct repository *r,
151                   struct bundle_header *header,
152                   int verbose)
153 {
154         /*
155          * Do fast check, then if any prereqs are missing then go line by line
156          * to be verbose about the errors
157          */
158         struct ref_list *p = &header->prerequisites;
159         struct rev_info revs;
160         const char *argv[] = {NULL, "--all", NULL};
161         struct commit *commit;
162         int i, ret = 0, req_nr;
163         const char *message = _("Repository lacks these prerequisite commits:");
164
165         if (!r || !r->objects || !r->objects->odb)
166                 return error(_("need a repository to verify a bundle"));
167
168         repo_init_revisions(r, &revs, NULL);
169         for (i = 0; i < p->nr; i++) {
170                 struct ref_list_entry *e = p->list + i;
171                 struct object *o = parse_object(r, &e->oid);
172                 if (o) {
173                         o->flags |= PREREQ_MARK;
174                         add_pending_object(&revs, o, e->name);
175                         continue;
176                 }
177                 if (++ret == 1)
178                         error("%s", message);
179                 error("%s %s", oid_to_hex(&e->oid), e->name);
180         }
181         if (revs.pending.nr != p->nr)
182                 return ret;
183         req_nr = revs.pending.nr;
184         setup_revisions(2, argv, &revs, NULL);
185
186         if (prepare_revision_walk(&revs))
187                 die(_("revision walk setup failed"));
188
189         i = req_nr;
190         while (i && (commit = get_revision(&revs)))
191                 if (commit->object.flags & PREREQ_MARK)
192                         i--;
193
194         for (i = 0; i < p->nr; i++) {
195                 struct ref_list_entry *e = p->list + i;
196                 struct object *o = parse_object(r, &e->oid);
197                 assert(o); /* otherwise we'd have returned early */
198                 if (o->flags & SHOWN)
199                         continue;
200                 if (++ret == 1)
201                         error("%s", message);
202                 error("%s %s", oid_to_hex(&e->oid), e->name);
203         }
204
205         /* Clean up objects used, as they will be reused. */
206         for (i = 0; i < p->nr; i++) {
207                 struct ref_list_entry *e = p->list + i;
208                 commit = lookup_commit_reference_gently(r, &e->oid, 1);
209                 if (commit)
210                         clear_commit_marks(commit, ALL_REV_FLAGS);
211         }
212
213         if (verbose) {
214                 struct ref_list *r;
215
216                 r = &header->references;
217                 printf_ln(Q_("The bundle contains this ref:",
218                              "The bundle contains these %d refs:",
219                              r->nr),
220                           r->nr);
221                 list_refs(r, 0, NULL);
222                 r = &header->prerequisites;
223                 if (!r->nr) {
224                         printf_ln(_("The bundle records a complete history."));
225                 } else {
226                         printf_ln(Q_("The bundle requires this ref:",
227                                      "The bundle requires these %d refs:",
228                                      r->nr),
229                                   r->nr);
230                         list_refs(r, 0, NULL);
231                 }
232         }
233         return ret;
234 }
235
236 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
237 {
238         return list_refs(&header->references, argc, argv);
239 }
240
241 static int is_tag_in_date_range(struct object *tag, struct rev_info *revs)
242 {
243         unsigned long size;
244         enum object_type type;
245         char *buf = NULL, *line, *lineend;
246         timestamp_t date;
247         int result = 1;
248
249         if (revs->max_age == -1 && revs->min_age == -1)
250                 goto out;
251
252         buf = read_object_file(&tag->oid, &type, &size);
253         if (!buf)
254                 goto out;
255         line = memmem(buf, size, "\ntagger ", 8);
256         if (!line++)
257                 goto out;
258         lineend = memchr(line, '\n', buf + size - line);
259         line = memchr(line, '>', lineend ? lineend - line : buf + size - line);
260         if (!line++)
261                 goto out;
262         date = parse_timestamp(line, NULL, 10);
263         result = (revs->max_age == -1 || revs->max_age < date) &&
264                 (revs->min_age == -1 || revs->min_age > date);
265 out:
266         free(buf);
267         return result;
268 }
269
270
271 /* Write the pack data to bundle_fd */
272 static int write_pack_data(int bundle_fd, struct rev_info *revs, struct argv_array *pack_options)
273 {
274         struct child_process pack_objects = CHILD_PROCESS_INIT;
275         int i;
276
277         argv_array_pushl(&pack_objects.args,
278                          "pack-objects",
279                          "--stdout", "--thin", "--delta-base-offset",
280                          NULL);
281         argv_array_pushv(&pack_objects.args, pack_options->argv);
282         pack_objects.in = -1;
283         pack_objects.out = bundle_fd;
284         pack_objects.git_cmd = 1;
285
286         /*
287          * start_command() will close our descriptor if it's >1. Duplicate it
288          * to avoid surprising the caller.
289          */
290         if (pack_objects.out > 1) {
291                 pack_objects.out = dup(pack_objects.out);
292                 if (pack_objects.out < 0) {
293                         error_errno(_("unable to dup bundle descriptor"));
294                         child_process_clear(&pack_objects);
295                         return -1;
296                 }
297         }
298
299         if (start_command(&pack_objects))
300                 return error(_("Could not spawn pack-objects"));
301
302         for (i = 0; i < revs->pending.nr; i++) {
303                 struct object *object = revs->pending.objects[i].item;
304                 if (object->flags & UNINTERESTING)
305                         write_or_die(pack_objects.in, "^", 1);
306                 write_or_die(pack_objects.in, oid_to_hex(&object->oid), the_hash_algo->hexsz);
307                 write_or_die(pack_objects.in, "\n", 1);
308         }
309         close(pack_objects.in);
310         if (finish_command(&pack_objects))
311                 return error(_("pack-objects died"));
312         return 0;
313 }
314
315 static int compute_and_write_prerequisites(int bundle_fd,
316                                            struct rev_info *revs,
317                                            int argc, const char **argv)
318 {
319         struct child_process rls = CHILD_PROCESS_INIT;
320         struct strbuf buf = STRBUF_INIT;
321         FILE *rls_fout;
322         int i;
323
324         argv_array_pushl(&rls.args,
325                          "rev-list", "--boundary", "--pretty=oneline",
326                          NULL);
327         for (i = 1; i < argc; i++)
328                 argv_array_push(&rls.args, argv[i]);
329         rls.out = -1;
330         rls.git_cmd = 1;
331         if (start_command(&rls))
332                 return -1;
333         rls_fout = xfdopen(rls.out, "r");
334         while (strbuf_getwholeline(&buf, rls_fout, '\n') != EOF) {
335                 struct object_id oid;
336                 if (buf.len > 0 && buf.buf[0] == '-') {
337                         write_or_die(bundle_fd, buf.buf, buf.len);
338                         if (!get_oid_hex(buf.buf + 1, &oid)) {
339                                 struct object *object = parse_object_or_die(&oid,
340                                                                             buf.buf);
341                                 object->flags |= UNINTERESTING;
342                                 add_pending_object(revs, object, buf.buf);
343                         }
344                 } else if (!get_oid_hex(buf.buf, &oid)) {
345                         struct object *object = parse_object_or_die(&oid,
346                                                                     buf.buf);
347                         object->flags |= SHOWN;
348                 }
349         }
350         strbuf_release(&buf);
351         fclose(rls_fout);
352         if (finish_command(&rls))
353                 return error(_("rev-list died"));
354         return 0;
355 }
356
357 /*
358  * Write out bundle refs based on the tips already
359  * parsed into revs.pending. As a side effect, may
360  * manipulate revs.pending to include additional
361  * necessary objects (like tags).
362  *
363  * Returns the number of refs written, or negative
364  * on error.
365  */
366 static int write_bundle_refs(int bundle_fd, struct rev_info *revs)
367 {
368         int i;
369         int ref_count = 0;
370
371         for (i = 0; i < revs->pending.nr; i++) {
372                 struct object_array_entry *e = revs->pending.objects + i;
373                 struct object_id oid;
374                 char *ref;
375                 const char *display_ref;
376                 int flag;
377
378                 if (e->item->flags & UNINTERESTING)
379                         continue;
380                 if (dwim_ref(e->name, strlen(e->name), &oid, &ref, 0) != 1)
381                         goto skip_write_ref;
382                 if (read_ref_full(e->name, RESOLVE_REF_READING, &oid, &flag))
383                         flag = 0;
384                 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
385
386                 if (e->item->type == OBJ_TAG &&
387                                 !is_tag_in_date_range(e->item, revs)) {
388                         e->item->flags |= UNINTERESTING;
389                         goto skip_write_ref;
390                 }
391
392                 /*
393                  * Make sure the refs we wrote out is correct; --max-count and
394                  * other limiting options could have prevented all the tips
395                  * from getting output.
396                  *
397                  * Non commit objects such as tags and blobs do not have
398                  * this issue as they are not affected by those extra
399                  * constraints.
400                  */
401                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
402                         warning(_("ref '%s' is excluded by the rev-list options"),
403                                 e->name);
404                         goto skip_write_ref;
405                 }
406                 /*
407                  * If you run "git bundle create bndl v1.0..v2.0", the
408                  * name of the positive ref is "v2.0" but that is the
409                  * commit that is referenced by the tag, and not the tag
410                  * itself.
411                  */
412                 if (!oideq(&oid, &e->item->oid)) {
413                         /*
414                          * Is this the positive end of a range expressed
415                          * in terms of a tag (e.g. v2.0 from the range
416                          * "v1.0..v2.0")?
417                          */
418                         struct commit *one = lookup_commit_reference(revs->repo, &oid);
419                         struct object *obj;
420
421                         if (e->item == &(one->object)) {
422                                 /*
423                                  * Need to include e->name as an
424                                  * independent ref to the pack-objects
425                                  * input, so that the tag is included
426                                  * in the output; otherwise we would
427                                  * end up triggering "empty bundle"
428                                  * error.
429                                  */
430                                 obj = parse_object_or_die(&oid, e->name);
431                                 obj->flags |= SHOWN;
432                                 add_pending_object(revs, obj, e->name);
433                         }
434                         goto skip_write_ref;
435                 }
436
437                 ref_count++;
438                 write_or_die(bundle_fd, oid_to_hex(&e->item->oid), the_hash_algo->hexsz);
439                 write_or_die(bundle_fd, " ", 1);
440                 write_or_die(bundle_fd, display_ref, strlen(display_ref));
441                 write_or_die(bundle_fd, "\n", 1);
442  skip_write_ref:
443                 free(ref);
444         }
445
446         /* end header */
447         write_or_die(bundle_fd, "\n", 1);
448         return ref_count;
449 }
450
451 int create_bundle(struct repository *r, const char *path,
452                   int argc, const char **argv, struct argv_array *pack_options)
453 {
454         struct lock_file lock = LOCK_INIT;
455         int bundle_fd = -1;
456         int bundle_to_stdout;
457         int ref_count = 0;
458         struct rev_info revs;
459
460         bundle_to_stdout = !strcmp(path, "-");
461         if (bundle_to_stdout)
462                 bundle_fd = 1;
463         else
464                 bundle_fd = hold_lock_file_for_update(&lock, path,
465                                                       LOCK_DIE_ON_ERROR);
466
467         /* write signature */
468         write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
469
470         /* init revs to list objects for pack-objects later */
471         save_commit_buffer = 0;
472         repo_init_revisions(r, &revs, NULL);
473
474         /* write prerequisites */
475         if (compute_and_write_prerequisites(bundle_fd, &revs, argc, argv))
476                 goto err;
477
478         argc = setup_revisions(argc, argv, &revs, NULL);
479
480         if (argc > 1) {
481                 error(_("unrecognized argument: %s"), argv[1]);
482                 goto err;
483         }
484
485         object_array_remove_duplicates(&revs.pending);
486
487         ref_count = write_bundle_refs(bundle_fd, &revs);
488         if (!ref_count)
489                 die(_("Refusing to create empty bundle."));
490         else if (ref_count < 0)
491                 goto err;
492
493         /* write pack */
494         if (write_pack_data(bundle_fd, &revs, pack_options))
495                 goto err;
496
497         if (!bundle_to_stdout) {
498                 if (commit_lock_file(&lock))
499                         die_errno(_("cannot create '%s'"), path);
500         }
501         return 0;
502 err:
503         rollback_lock_file(&lock);
504         return -1;
505 }
506
507 int unbundle(struct repository *r, struct bundle_header *header,
508              int bundle_fd, int flags)
509 {
510         const char *argv_index_pack[] = {"index-pack",
511                                          "--fix-thin", "--stdin", NULL, NULL};
512         struct child_process ip = CHILD_PROCESS_INIT;
513
514         if (flags & BUNDLE_VERBOSE)
515                 argv_index_pack[3] = "-v";
516
517         if (verify_bundle(r, header, 0))
518                 return -1;
519         ip.argv = argv_index_pack;
520         ip.in = bundle_fd;
521         ip.no_stdout = 1;
522         ip.git_cmd = 1;
523         if (run_command(&ip))
524                 return error(_("index-pack died"));
525         return 0;
526 }