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