mingw: short-circuit the conversion of `/dev/null` to UTF-16
[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)
253 {
254         struct child_process pack_objects = CHILD_PROCESS_INIT;
255         int i;
256
257         argv_array_pushl(&pack_objects.args,
258                          "pack-objects", "--all-progress-implied",
259                          "--stdout", "--thin", "--delta-base-offset",
260                          NULL);
261         pack_objects.in = -1;
262         pack_objects.out = bundle_fd;
263         pack_objects.git_cmd = 1;
264
265         /*
266          * start_command() will close our descriptor if it's >1. Duplicate it
267          * to avoid surprising the caller.
268          */
269         if (pack_objects.out > 1) {
270                 pack_objects.out = dup(pack_objects.out);
271                 if (pack_objects.out < 0) {
272                         error_errno(_("unable to dup bundle descriptor"));
273                         child_process_clear(&pack_objects);
274                         return -1;
275                 }
276         }
277
278         if (start_command(&pack_objects))
279                 return error(_("Could not spawn pack-objects"));
280
281         for (i = 0; i < revs->pending.nr; i++) {
282                 struct object *object = revs->pending.objects[i].item;
283                 if (object->flags & UNINTERESTING)
284                         write_or_die(pack_objects.in, "^", 1);
285                 write_or_die(pack_objects.in, oid_to_hex(&object->oid), the_hash_algo->hexsz);
286                 write_or_die(pack_objects.in, "\n", 1);
287         }
288         close(pack_objects.in);
289         if (finish_command(&pack_objects))
290                 return error(_("pack-objects died"));
291         return 0;
292 }
293
294 static int compute_and_write_prerequisites(int bundle_fd,
295                                            struct rev_info *revs,
296                                            int argc, const char **argv)
297 {
298         struct child_process rls = CHILD_PROCESS_INIT;
299         struct strbuf buf = STRBUF_INIT;
300         FILE *rls_fout;
301         int i;
302
303         argv_array_pushl(&rls.args,
304                          "rev-list", "--boundary", "--pretty=oneline",
305                          NULL);
306         for (i = 1; i < argc; i++)
307                 argv_array_push(&rls.args, argv[i]);
308         rls.out = -1;
309         rls.git_cmd = 1;
310         if (start_command(&rls))
311                 return -1;
312         rls_fout = xfdopen(rls.out, "r");
313         while (strbuf_getwholeline(&buf, rls_fout, '\n') != EOF) {
314                 struct object_id oid;
315                 if (buf.len > 0 && buf.buf[0] == '-') {
316                         write_or_die(bundle_fd, buf.buf, buf.len);
317                         if (!get_oid_hex(buf.buf + 1, &oid)) {
318                                 struct object *object = parse_object_or_die(&oid,
319                                                                             buf.buf);
320                                 object->flags |= UNINTERESTING;
321                                 add_pending_object(revs, object, buf.buf);
322                         }
323                 } else if (!get_oid_hex(buf.buf, &oid)) {
324                         struct object *object = parse_object_or_die(&oid,
325                                                                     buf.buf);
326                         object->flags |= SHOWN;
327                 }
328         }
329         strbuf_release(&buf);
330         fclose(rls_fout);
331         if (finish_command(&rls))
332                 return error(_("rev-list died"));
333         return 0;
334 }
335
336 /*
337  * Write out bundle refs based on the tips already
338  * parsed into revs.pending. As a side effect, may
339  * manipulate revs.pending to include additional
340  * necessary objects (like tags).
341  *
342  * Returns the number of refs written, or negative
343  * on error.
344  */
345 static int write_bundle_refs(int bundle_fd, struct rev_info *revs)
346 {
347         int i;
348         int ref_count = 0;
349
350         for (i = 0; i < revs->pending.nr; i++) {
351                 struct object_array_entry *e = revs->pending.objects + i;
352                 struct object_id oid;
353                 char *ref;
354                 const char *display_ref;
355                 int flag;
356
357                 if (e->item->flags & UNINTERESTING)
358                         continue;
359                 if (dwim_ref(e->name, strlen(e->name), &oid, &ref) != 1)
360                         goto skip_write_ref;
361                 if (read_ref_full(e->name, RESOLVE_REF_READING, &oid, &flag))
362                         flag = 0;
363                 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
364
365                 if (e->item->type == OBJ_TAG &&
366                                 !is_tag_in_date_range(e->item, revs)) {
367                         e->item->flags |= UNINTERESTING;
368                         goto skip_write_ref;
369                 }
370
371                 /*
372                  * Make sure the refs we wrote out is correct; --max-count and
373                  * other limiting options could have prevented all the tips
374                  * from getting output.
375                  *
376                  * Non commit objects such as tags and blobs do not have
377                  * this issue as they are not affected by those extra
378                  * constraints.
379                  */
380                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
381                         warning(_("ref '%s' is excluded by the rev-list options"),
382                                 e->name);
383                         goto skip_write_ref;
384                 }
385                 /*
386                  * If you run "git bundle create bndl v1.0..v2.0", the
387                  * name of the positive ref is "v2.0" but that is the
388                  * commit that is referenced by the tag, and not the tag
389                  * itself.
390                  */
391                 if (!oideq(&oid, &e->item->oid)) {
392                         /*
393                          * Is this the positive end of a range expressed
394                          * in terms of a tag (e.g. v2.0 from the range
395                          * "v1.0..v2.0")?
396                          */
397                         struct commit *one = lookup_commit_reference(revs->repo, &oid);
398                         struct object *obj;
399
400                         if (e->item == &(one->object)) {
401                                 /*
402                                  * Need to include e->name as an
403                                  * independent ref to the pack-objects
404                                  * input, so that the tag is included
405                                  * in the output; otherwise we would
406                                  * end up triggering "empty bundle"
407                                  * error.
408                                  */
409                                 obj = parse_object_or_die(&oid, e->name);
410                                 obj->flags |= SHOWN;
411                                 add_pending_object(revs, obj, e->name);
412                         }
413                         goto skip_write_ref;
414                 }
415
416                 ref_count++;
417                 write_or_die(bundle_fd, oid_to_hex(&e->item->oid), the_hash_algo->hexsz);
418                 write_or_die(bundle_fd, " ", 1);
419                 write_or_die(bundle_fd, display_ref, strlen(display_ref));
420                 write_or_die(bundle_fd, "\n", 1);
421  skip_write_ref:
422                 free(ref);
423         }
424
425         /* end header */
426         write_or_die(bundle_fd, "\n", 1);
427         return ref_count;
428 }
429
430 int create_bundle(struct repository *r, const char *path,
431                   int argc, const char **argv)
432 {
433         struct lock_file lock = LOCK_INIT;
434         int bundle_fd = -1;
435         int bundle_to_stdout;
436         int ref_count = 0;
437         struct rev_info revs;
438
439         bundle_to_stdout = !strcmp(path, "-");
440         if (bundle_to_stdout)
441                 bundle_fd = 1;
442         else
443                 bundle_fd = hold_lock_file_for_update(&lock, path,
444                                                       LOCK_DIE_ON_ERROR);
445
446         /* write signature */
447         write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
448
449         /* init revs to list objects for pack-objects later */
450         save_commit_buffer = 0;
451         repo_init_revisions(r, &revs, NULL);
452
453         /* write prerequisites */
454         if (compute_and_write_prerequisites(bundle_fd, &revs, argc, argv))
455                 goto err;
456
457         argc = setup_revisions(argc, argv, &revs, NULL);
458
459         if (argc > 1) {
460                 error(_("unrecognized argument: %s"), argv[1]);
461                 goto err;
462         }
463
464         object_array_remove_duplicates(&revs.pending);
465
466         ref_count = write_bundle_refs(bundle_fd, &revs);
467         if (!ref_count)
468                 die(_("Refusing to create empty bundle."));
469         else if (ref_count < 0)
470                 goto err;
471
472         /* write pack */
473         if (write_pack_data(bundle_fd, &revs))
474                 goto err;
475
476         if (!bundle_to_stdout) {
477                 if (commit_lock_file(&lock))
478                         die_errno(_("cannot create '%s'"), path);
479         }
480         return 0;
481 err:
482         rollback_lock_file(&lock);
483         return -1;
484 }
485
486 int unbundle(struct repository *r, struct bundle_header *header,
487              int bundle_fd, int flags)
488 {
489         const char *argv_index_pack[] = {"index-pack",
490                                          "--fix-thin", "--stdin", NULL, NULL};
491         struct child_process ip = CHILD_PROCESS_INIT;
492
493         if (flags & BUNDLE_VERBOSE)
494                 argv_index_pack[3] = "-v";
495
496         if (verify_bundle(r, header, 0))
497                 return -1;
498         ip.argv = argv_index_pack;
499         ip.in = bundle_fd;
500         ip.no_stdout = 1;
501         ip.git_cmd = 1;
502         if (run_command(&ip))
503                 return error(_("index-pack died"));
504         return 0;
505 }