Merge branch 'ad/cygwin-wants-rename' into maint
[git] / bundle.c
1 #include "cache.h"
2 #include "lockfile.h"
3 #include "bundle.h"
4 #include "object.h"
5 #include "commit.h"
6 #include "diff.h"
7 #include "revision.h"
8 #include "list-objects.h"
9 #include "run-command.h"
10 #include "refs.h"
11 #include "argv-array.h"
12
13 static const char bundle_signature[] = "# v2 git bundle\n";
14
15 static void add_to_ref_list(const unsigned char *sha1, const char *name,
16                 struct ref_list *list)
17 {
18         ALLOC_GROW(list->list, list->nr + 1, list->alloc);
19         hashcpy(list->list[list->nr].sha1, sha1);
20         list->list[list->nr].name = xstrdup(name);
21         list->nr++;
22 }
23
24 static int parse_bundle_header(int fd, struct bundle_header *header,
25                                const char *report_path)
26 {
27         struct strbuf buf = STRBUF_INIT;
28         int status = 0;
29
30         /* The bundle header begins with the signature */
31         if (strbuf_getwholeline_fd(&buf, fd, '\n') ||
32             strcmp(buf.buf, bundle_signature)) {
33                 if (report_path)
34                         error(_("'%s' does not look like a v2 bundle file"),
35                               report_path);
36                 status = -1;
37                 goto abort;
38         }
39
40         /* The bundle header ends with an empty line */
41         while (!strbuf_getwholeline_fd(&buf, fd, '\n') &&
42                buf.len && buf.buf[0] != '\n') {
43                 unsigned char sha1[20];
44                 int is_prereq = 0;
45
46                 if (*buf.buf == '-') {
47                         is_prereq = 1;
48                         strbuf_remove(&buf, 0, 1);
49                 }
50                 strbuf_rtrim(&buf);
51
52                 /*
53                  * Tip lines have object name, SP, and refname.
54                  * Prerequisites have object name that is optionally
55                  * followed by SP and subject line.
56                  */
57                 if (get_sha1_hex(buf.buf, sha1) ||
58                     (buf.len > 40 && !isspace(buf.buf[40])) ||
59                     (!is_prereq && buf.len <= 40)) {
60                         if (report_path)
61                                 error(_("unrecognized header: %s%s (%d)"),
62                                       (is_prereq ? "-" : ""), buf.buf, (int)buf.len);
63                         status = -1;
64                         break;
65                 } else {
66                         if (is_prereq)
67                                 add_to_ref_list(sha1, "", &header->prerequisites);
68                         else
69                                 add_to_ref_list(sha1, buf.buf + 41, &header->references);
70                 }
71         }
72
73  abort:
74         if (status) {
75                 close(fd);
76                 fd = -1;
77         }
78         strbuf_release(&buf);
79         return fd;
80 }
81
82 int read_bundle_header(const char *path, struct bundle_header *header)
83 {
84         int fd = open(path, O_RDONLY);
85
86         if (fd < 0)
87                 return error(_("could not open '%s'"), path);
88         return parse_bundle_header(fd, header, path);
89 }
90
91 int is_bundle(const char *path, int quiet)
92 {
93         struct bundle_header header;
94         int fd = open(path, O_RDONLY);
95
96         if (fd < 0)
97                 return 0;
98         memset(&header, 0, sizeof(header));
99         fd = parse_bundle_header(fd, &header, quiet ? NULL : path);
100         if (fd >= 0)
101                 close(fd);
102         return (fd >= 0);
103 }
104
105 static int list_refs(struct ref_list *r, int argc, const char **argv)
106 {
107         int i;
108
109         for (i = 0; i < r->nr; i++) {
110                 if (argc > 1) {
111                         int j;
112                         for (j = 1; j < argc; j++)
113                                 if (!strcmp(r->list[i].name, argv[j]))
114                                         break;
115                         if (j == argc)
116                                 continue;
117                 }
118                 printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
119                                 r->list[i].name);
120         }
121         return 0;
122 }
123
124 /* Remember to update object flag allocation in object.h */
125 #define PREREQ_MARK (1u<<16)
126
127 int verify_bundle(struct bundle_header *header, int verbose)
128 {
129         /*
130          * Do fast check, then if any prereqs are missing then go line by line
131          * to be verbose about the errors
132          */
133         struct ref_list *p = &header->prerequisites;
134         struct rev_info revs;
135         const char *argv[] = {NULL, "--all", NULL};
136         struct object_array refs;
137         struct commit *commit;
138         int i, ret = 0, req_nr;
139         const char *message = _("Repository lacks these prerequisite commits:");
140
141         init_revisions(&revs, NULL);
142         for (i = 0; i < p->nr; i++) {
143                 struct ref_list_entry *e = p->list + i;
144                 struct object *o = parse_object(e->sha1);
145                 if (o) {
146                         o->flags |= PREREQ_MARK;
147                         add_pending_object(&revs, o, e->name);
148                         continue;
149                 }
150                 if (++ret == 1)
151                         error("%s", message);
152                 error("%s %s", sha1_to_hex(e->sha1), e->name);
153         }
154         if (revs.pending.nr != p->nr)
155                 return ret;
156         req_nr = revs.pending.nr;
157         setup_revisions(2, argv, &revs, NULL);
158
159         refs = revs.pending;
160         revs.leak_pending = 1;
161
162         if (prepare_revision_walk(&revs))
163                 die(_("revision walk setup failed"));
164
165         i = req_nr;
166         while (i && (commit = get_revision(&revs)))
167                 if (commit->object.flags & PREREQ_MARK)
168                         i--;
169
170         for (i = 0; i < req_nr; i++)
171                 if (!(refs.objects[i].item->flags & SHOWN)) {
172                         if (++ret == 1)
173                                 error("%s", message);
174                         error("%s %s", oid_to_hex(&refs.objects[i].item->oid),
175                                 refs.objects[i].name);
176                 }
177
178         clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
179         free(refs.objects);
180
181         if (verbose) {
182                 struct ref_list *r;
183
184                 r = &header->references;
185                 printf_ln(Q_("The bundle contains this ref:",
186                              "The bundle contains these %d refs:",
187                              r->nr),
188                           r->nr);
189                 list_refs(r, 0, NULL);
190                 r = &header->prerequisites;
191                 if (!r->nr) {
192                         printf_ln(_("The bundle records a complete history."));
193                 } else {
194                         printf_ln(Q_("The bundle requires this ref:",
195                                      "The bundle requires these %d refs:",
196                                      r->nr),
197                                   r->nr);
198                         list_refs(r, 0, NULL);
199                 }
200         }
201         return ret;
202 }
203
204 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
205 {
206         return list_refs(&header->references, argc, argv);
207 }
208
209 static int is_tag_in_date_range(struct object *tag, struct rev_info *revs)
210 {
211         unsigned long size;
212         enum object_type type;
213         char *buf = NULL, *line, *lineend;
214         unsigned long date;
215         int result = 1;
216
217         if (revs->max_age == -1 && revs->min_age == -1)
218                 goto out;
219
220         buf = read_sha1_file(tag->oid.hash, &type, &size);
221         if (!buf)
222                 goto out;
223         line = memmem(buf, size, "\ntagger ", 8);
224         if (!line++)
225                 goto out;
226         lineend = memchr(line, '\n', buf + size - line);
227         line = memchr(line, '>', lineend ? lineend - line : buf + size - line);
228         if (!line++)
229                 goto out;
230         date = strtoul(line, NULL, 10);
231         result = (revs->max_age == -1 || revs->max_age < date) &&
232                 (revs->min_age == -1 || revs->min_age > date);
233 out:
234         free(buf);
235         return result;
236 }
237
238
239 /* Write the pack data to bundle_fd, then close it if it is > 1. */
240 static int write_pack_data(int bundle_fd, struct rev_info *revs)
241 {
242         struct child_process pack_objects = CHILD_PROCESS_INIT;
243         int i;
244
245         argv_array_pushl(&pack_objects.args,
246                          "pack-objects", "--all-progress-implied",
247                          "--stdout", "--thin", "--delta-base-offset",
248                          NULL);
249         pack_objects.in = -1;
250         pack_objects.out = bundle_fd;
251         pack_objects.git_cmd = 1;
252         if (start_command(&pack_objects))
253                 return error(_("Could not spawn pack-objects"));
254
255         for (i = 0; i < revs->pending.nr; i++) {
256                 struct object *object = revs->pending.objects[i].item;
257                 if (object->flags & UNINTERESTING)
258                         write_or_die(pack_objects.in, "^", 1);
259                 write_or_die(pack_objects.in, oid_to_hex(&object->oid), GIT_SHA1_HEXSZ);
260                 write_or_die(pack_objects.in, "\n", 1);
261         }
262         close(pack_objects.in);
263         if (finish_command(&pack_objects))
264                 return error(_("pack-objects died"));
265         return 0;
266 }
267
268 static int compute_and_write_prerequisites(int bundle_fd,
269                                            struct rev_info *revs,
270                                            int argc, const char **argv)
271 {
272         struct child_process rls = CHILD_PROCESS_INIT;
273         struct strbuf buf = STRBUF_INIT;
274         FILE *rls_fout;
275         int i;
276
277         argv_array_pushl(&rls.args,
278                          "rev-list", "--boundary", "--pretty=oneline",
279                          NULL);
280         for (i = 1; i < argc; i++)
281                 argv_array_push(&rls.args, argv[i]);
282         rls.out = -1;
283         rls.git_cmd = 1;
284         if (start_command(&rls))
285                 return -1;
286         rls_fout = xfdopen(rls.out, "r");
287         while (strbuf_getwholeline(&buf, rls_fout, '\n') != EOF) {
288                 unsigned char sha1[20];
289                 if (buf.len > 0 && buf.buf[0] == '-') {
290                         write_or_die(bundle_fd, buf.buf, buf.len);
291                         if (!get_sha1_hex(buf.buf + 1, sha1)) {
292                                 struct object *object = parse_object_or_die(sha1, buf.buf);
293                                 object->flags |= UNINTERESTING;
294                                 add_pending_object(revs, object, buf.buf);
295                         }
296                 } else if (!get_sha1_hex(buf.buf, sha1)) {
297                         struct object *object = parse_object_or_die(sha1, buf.buf);
298                         object->flags |= SHOWN;
299                 }
300         }
301         strbuf_release(&buf);
302         fclose(rls_fout);
303         if (finish_command(&rls))
304                 return error(_("rev-list died"));
305         return 0;
306 }
307
308 /*
309  * Write out bundle refs based on the tips already
310  * parsed into revs.pending. As a side effect, may
311  * manipulate revs.pending to include additional
312  * necessary objects (like tags).
313  *
314  * Returns the number of refs written, or negative
315  * on error.
316  */
317 static int write_bundle_refs(int bundle_fd, struct rev_info *revs)
318 {
319         int i;
320         int ref_count = 0;
321
322         for (i = 0; i < revs->pending.nr; i++) {
323                 struct object_array_entry *e = revs->pending.objects + i;
324                 struct object_id oid;
325                 char *ref;
326                 const char *display_ref;
327                 int flag;
328
329                 if (e->item->flags & UNINTERESTING)
330                         continue;
331                 if (dwim_ref(e->name, strlen(e->name), oid.hash, &ref) != 1)
332                         goto skip_write_ref;
333                 if (read_ref_full(e->name, RESOLVE_REF_READING, oid.hash, &flag))
334                         flag = 0;
335                 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
336
337                 if (e->item->type == OBJ_TAG &&
338                                 !is_tag_in_date_range(e->item, revs)) {
339                         e->item->flags |= UNINTERESTING;
340                         goto skip_write_ref;
341                 }
342
343                 /*
344                  * Make sure the refs we wrote out is correct; --max-count and
345                  * other limiting options could have prevented all the tips
346                  * from getting output.
347                  *
348                  * Non commit objects such as tags and blobs do not have
349                  * this issue as they are not affected by those extra
350                  * constraints.
351                  */
352                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
353                         warning(_("ref '%s' is excluded by the rev-list options"),
354                                 e->name);
355                         goto skip_write_ref;
356                 }
357                 /*
358                  * If you run "git bundle create bndl v1.0..v2.0", the
359                  * name of the positive ref is "v2.0" but that is the
360                  * commit that is referenced by the tag, and not the tag
361                  * itself.
362                  */
363                 if (oidcmp(&oid, &e->item->oid)) {
364                         /*
365                          * Is this the positive end of a range expressed
366                          * in terms of a tag (e.g. v2.0 from the range
367                          * "v1.0..v2.0")?
368                          */
369                         struct commit *one = lookup_commit_reference(oid.hash);
370                         struct object *obj;
371
372                         if (e->item == &(one->object)) {
373                                 /*
374                                  * Need to include e->name as an
375                                  * independent ref to the pack-objects
376                                  * input, so that the tag is included
377                                  * in the output; otherwise we would
378                                  * end up triggering "empty bundle"
379                                  * error.
380                                  */
381                                 obj = parse_object_or_die(oid.hash, e->name);
382                                 obj->flags |= SHOWN;
383                                 add_pending_object(revs, obj, e->name);
384                         }
385                         goto skip_write_ref;
386                 }
387
388                 ref_count++;
389                 write_or_die(bundle_fd, oid_to_hex(&e->item->oid), 40);
390                 write_or_die(bundle_fd, " ", 1);
391                 write_or_die(bundle_fd, display_ref, strlen(display_ref));
392                 write_or_die(bundle_fd, "\n", 1);
393  skip_write_ref:
394                 free(ref);
395         }
396
397         /* end header */
398         write_or_die(bundle_fd, "\n", 1);
399         return ref_count;
400 }
401
402 int create_bundle(struct bundle_header *header, const char *path,
403                   int argc, const char **argv)
404 {
405         static struct lock_file lock;
406         int bundle_fd = -1;
407         int bundle_to_stdout;
408         int ref_count = 0;
409         struct rev_info revs;
410
411         bundle_to_stdout = !strcmp(path, "-");
412         if (bundle_to_stdout)
413                 bundle_fd = 1;
414         else {
415                 bundle_fd = hold_lock_file_for_update(&lock, path,
416                                                       LOCK_DIE_ON_ERROR);
417
418                 /*
419                  * write_pack_data() will close the fd passed to it,
420                  * but commit_lock_file() will also try to close the
421                  * lockfile's fd. So make a copy of the file
422                  * descriptor to avoid trying to close it twice.
423                  */
424                 bundle_fd = dup(bundle_fd);
425                 if (bundle_fd < 0)
426                         die_errno("unable to dup file descriptor");
427         }
428
429         /* write signature */
430         write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
431
432         /* init revs to list objects for pack-objects later */
433         save_commit_buffer = 0;
434         init_revisions(&revs, NULL);
435
436         /* write prerequisites */
437         if (compute_and_write_prerequisites(bundle_fd, &revs, argc, argv))
438                 return -1;
439
440         argc = setup_revisions(argc, argv, &revs, NULL);
441
442         if (argc > 1)
443                 return error(_("unrecognized argument: %s"), argv[1]);
444
445         object_array_remove_duplicates(&revs.pending);
446
447         ref_count = write_bundle_refs(bundle_fd, &revs);
448         if (!ref_count)
449                 die(_("Refusing to create empty bundle."));
450         else if (ref_count < 0)
451                 return -1;
452
453         /* write pack */
454         if (write_pack_data(bundle_fd, &revs))
455                 return -1;
456
457         if (!bundle_to_stdout) {
458                 if (commit_lock_file(&lock))
459                         die_errno(_("cannot create '%s'"), path);
460         }
461         return 0;
462 }
463
464 int unbundle(struct bundle_header *header, int bundle_fd, int flags)
465 {
466         const char *argv_index_pack[] = {"index-pack",
467                                          "--fix-thin", "--stdin", NULL, NULL};
468         struct child_process ip = CHILD_PROCESS_INIT;
469
470         if (flags & BUNDLE_VERBOSE)
471                 argv_index_pack[3] = "-v";
472
473         if (verify_bundle(header, 0))
474                 return -1;
475         ip.argv = argv_index_pack;
476         ip.in = bundle_fd;
477         ip.no_stdout = 1;
478         ip.git_cmd = 1;
479         if (run_command(&ip))
480                 return error(_("index-pack died"));
481         return 0;
482 }