git-commit: Allow to amend a merge commit that does not change the tree
[git/ericb.git] / bundle.c
blob9b9b9166df05e984dc571462f333aeaee9cdcd23
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"
11 static const char bundle_signature[] = "# v2 git bundle\n";
13 static void add_to_ref_list(const unsigned char *sha1, const char *name,
14 struct ref_list *list)
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]));
21 memcpy(list->list[list->nr].sha1, sha1, 20);
22 list->list[list->nr].name = xstrdup(name);
23 list->nr++;
26 /* returns an fd */
27 int read_bundle_header(const char *path, struct bundle_header *header)
29 char buffer[1024];
30 int fd;
31 long fpos;
32 FILE *ffd = fopen(path, "rb");
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);
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;
51 if (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;
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);
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;
72 static int list_refs(struct ref_list *r, int argc, const char **argv)
74 int i;
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;
85 printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
86 r->list[i].name);
88 return 0;
91 #define PREREQ_MARK (1u<<16)
93 int verify_bundle(struct bundle_header *header, int verbose)
96 * Do fast check, then if any prereqs are missing then go line by line
97 * to be verbose about the errors
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:";
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;
116 if (++ret == 1)
117 error(message);
118 error("%s %s", sha1_to_hex(e->sha1), e->name);
120 if (revs.pending.nr != p->nr)
121 return ret;
122 req_nr = revs.pending.nr;
123 setup_revisions(2, argv, &revs, NULL);
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);
131 prepare_revision_walk(&revs);
133 i = req_nr;
134 while (i && (commit = get_revision(&revs)))
135 if (commit->object.flags & PREREQ_MARK)
136 i--;
138 for (i = 0; i < req_nr; i++)
139 if (!(refs.objects[i].item->flags & SHOWN)) {
140 if (++ret == 1)
141 error(message);
142 error("%s %s", sha1_to_hex(refs.objects[i].item->sha1),
143 refs.objects[i].name);
146 for (i = 0; i < refs.nr; i++)
147 clear_commit_marks((struct commit *)refs.objects[i].item, -1);
149 if (verbose) {
150 struct ref_list *r;
152 r = &header->references;
153 printf("The bundle contains %d ref%s\n",
154 r->nr, (1 < r->nr) ? "s" : "");
155 list_refs(r, 0, NULL);
156 r = &header->prerequisites;
157 printf("The bundle requires these %d ref%s\n",
158 r->nr, (1 < r->nr) ? "s" : "");
159 list_refs(r, 0, NULL);
161 return ret;
164 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
166 return list_refs(&header->references, argc, argv);
169 int create_bundle(struct bundle_header *header, const char *path,
170 int argc, const char **argv)
172 static struct lock_file lock;
173 int bundle_fd = -1;
174 int bundle_to_stdout;
175 const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
176 const char **argv_pack = xmalloc(5 * sizeof(const char *));
177 int i, ref_count = 0;
178 char buffer[1024];
179 struct rev_info revs;
180 struct child_process rls;
181 FILE *rls_fout;
183 bundle_to_stdout = !strcmp(path, "-");
184 if (bundle_to_stdout)
185 bundle_fd = 1;
186 else
187 bundle_fd = hold_lock_file_for_update(&lock, path, 1);
189 /* write signature */
190 write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
192 /* init revs to list objects for pack-objects later */
193 save_commit_buffer = 0;
194 init_revisions(&revs, NULL);
196 /* write prerequisites */
197 memcpy(argv_boundary + 3, argv + 1, argc * sizeof(const char *));
198 argv_boundary[0] = "rev-list";
199 argv_boundary[1] = "--boundary";
200 argv_boundary[2] = "--pretty=oneline";
201 argv_boundary[argc + 2] = NULL;
202 memset(&rls, 0, sizeof(rls));
203 rls.argv = argv_boundary;
204 rls.out = -1;
205 rls.git_cmd = 1;
206 if (start_command(&rls))
207 return -1;
208 rls_fout = fdopen(rls.out, "r");
209 while (fgets(buffer, sizeof(buffer), rls_fout)) {
210 unsigned char sha1[20];
211 if (buffer[0] == '-') {
212 write_or_die(bundle_fd, buffer, strlen(buffer));
213 if (!get_sha1_hex(buffer + 1, sha1)) {
214 struct object *object = parse_object(sha1);
215 object->flags |= UNINTERESTING;
216 add_pending_object(&revs, object, buffer);
218 } else if (!get_sha1_hex(buffer, sha1)) {
219 struct object *object = parse_object(sha1);
220 object->flags |= SHOWN;
223 fclose(rls_fout);
224 if (finish_command(&rls))
225 return error("rev-list died");
227 /* write references */
228 argc = setup_revisions(argc, argv, &revs, NULL);
229 if (argc > 1)
230 return error("unrecognized argument: %s'", argv[1]);
232 for (i = 0; i < revs.pending.nr; i++) {
233 struct object_array_entry *e = revs.pending.objects + i;
234 unsigned char sha1[20];
235 char *ref;
236 const char *display_ref;
237 int flag;
239 if (e->item->flags & UNINTERESTING)
240 continue;
241 if (dwim_ref(e->name, strlen(e->name), sha1, &ref) != 1)
242 continue;
243 if (!resolve_ref(e->name, sha1, 1, &flag))
244 flag = 0;
245 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
248 * Make sure the refs we wrote out is correct; --max-count and
249 * other limiting options could have prevented all the tips
250 * from getting output.
252 * Non commit objects such as tags and blobs do not have
253 * this issue as they are not affected by those extra
254 * constraints.
256 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
257 warning("ref '%s' is excluded by the rev-list options",
258 e->name);
259 free(ref);
260 continue;
263 * If you run "git bundle create bndl v1.0..v2.0", the
264 * name of the positive ref is "v2.0" but that is the
265 * commit that is referenced by the tag, and not the tag
266 * itself.
268 if (hashcmp(sha1, e->item->sha1)) {
270 * Is this the positive end of a range expressed
271 * in terms of a tag (e.g. v2.0 from the range
272 * "v1.0..v2.0")?
274 struct commit *one = lookup_commit_reference(sha1);
275 struct object *obj;
277 if (e->item == &(one->object)) {
279 * Need to include e->name as an
280 * independent ref to the pack-objects
281 * input, so that the tag is included
282 * in the output; otherwise we would
283 * end up triggering "empty bundle"
284 * error.
286 obj = parse_object(sha1);
287 obj->flags |= SHOWN;
288 add_pending_object(&revs, obj, e->name);
290 free(ref);
291 continue;
294 ref_count++;
295 write_or_die(bundle_fd, sha1_to_hex(e->item->sha1), 40);
296 write_or_die(bundle_fd, " ", 1);
297 write_or_die(bundle_fd, display_ref, strlen(display_ref));
298 write_or_die(bundle_fd, "\n", 1);
299 free(ref);
301 if (!ref_count)
302 die ("Refusing to create empty bundle.");
304 /* end header */
305 write_or_die(bundle_fd, "\n", 1);
307 /* write pack */
308 argv_pack[0] = "pack-objects";
309 argv_pack[1] = "--all-progress";
310 argv_pack[2] = "--stdout";
311 argv_pack[3] = "--thin";
312 argv_pack[4] = NULL;
313 memset(&rls, 0, sizeof(rls));
314 rls.argv = argv_pack;
315 rls.in = -1;
316 rls.out = bundle_fd;
317 rls.git_cmd = 1;
318 if (start_command(&rls))
319 return error("Could not spawn pack-objects");
320 for (i = 0; i < revs.pending.nr; i++) {
321 struct object *object = revs.pending.objects[i].item;
322 if (object->flags & UNINTERESTING)
323 write(rls.in, "^", 1);
324 write(rls.in, sha1_to_hex(object->sha1), 40);
325 write(rls.in, "\n", 1);
327 if (finish_command(&rls))
328 return error ("pack-objects died");
329 close(bundle_fd);
330 if (!bundle_to_stdout)
331 commit_lock_file(&lock);
332 return 0;
335 int unbundle(struct bundle_header *header, int bundle_fd)
337 const char *argv_index_pack[] = {"index-pack",
338 "--fix-thin", "--stdin", NULL};
339 struct child_process ip;
341 if (verify_bundle(header, 0))
342 return -1;
343 memset(&ip, 0, sizeof(ip));
344 ip.argv = argv_index_pack;
345 ip.in = bundle_fd;
346 ip.no_stdout = 1;
347 ip.git_cmd = 1;
348 if (run_command(&ip))
349 return error("index-pack died");
350 return 0;