Support gitlinks in fast-import.
[git/git.git] / builtin-fast-export.c
1 /*
2 * "git fast-export" builtin command
3 *
4 * Copyright (C) 2007 Johannes E. Schindelin
5 */
6 #include "builtin.h"
7 #include "cache.h"
8 #include "commit.h"
9 #include "object.h"
10 #include "tag.h"
11 #include "diff.h"
12 #include "diffcore.h"
13 #include "log-tree.h"
14 #include "revision.h"
15 #include "decorate.h"
16 #include "path-list.h"
17 #include "utf8.h"
18 #include "parse-options.h"
19
20 static const char *fast_export_usage[] = {
21 "git fast-export [rev-list-opts]",
22 NULL
23 };
24
25 static int progress;
26 static enum { VERBATIM, WARN, STRIP, ABORT } signed_tag_mode = ABORT;
27
28 static int parse_opt_signed_tag_mode(const struct option *opt,
29 const char *arg, int unset)
30 {
31 if (unset || !strcmp(arg, "abort"))
32 signed_tag_mode = ABORT;
33 else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
34 signed_tag_mode = VERBATIM;
35 else if (!strcmp(arg, "warn"))
36 signed_tag_mode = WARN;
37 else if (!strcmp(arg, "strip"))
38 signed_tag_mode = STRIP;
39 else
40 return error("Unknown signed-tag mode: %s", arg);
41 return 0;
42 }
43
44 static struct decoration idnums;
45 static uint32_t last_idnum;
46
47 static int has_unshown_parent(struct commit *commit)
48 {
49 struct commit_list *parent;
50
51 for (parent = commit->parents; parent; parent = parent->next)
52 if (!(parent->item->object.flags & SHOWN) &&
53 !(parent->item->object.flags & UNINTERESTING))
54 return 1;
55 return 0;
56 }
57
58 /* Since intptr_t is C99, we do not use it here */
59 static inline uint32_t *mark_to_ptr(uint32_t mark)
60 {
61 return ((uint32_t *)NULL) + mark;
62 }
63
64 static inline uint32_t ptr_to_mark(void * mark)
65 {
66 return (uint32_t *)mark - (uint32_t *)NULL;
67 }
68
69 static inline void mark_object(struct object *object, uint32_t mark)
70 {
71 add_decoration(&idnums, object, mark_to_ptr(mark));
72 }
73
74 static inline void mark_next_object(struct object *object)
75 {
76 mark_object(object, ++last_idnum);
77 }
78
79 static int get_object_mark(struct object *object)
80 {
81 void *decoration = lookup_decoration(&idnums, object);
82 if (!decoration)
83 return 0;
84 return ptr_to_mark(decoration);
85 }
86
87 static void show_progress(void)
88 {
89 static int counter = 0;
90 if (!progress)
91 return;
92 if ((++counter % progress) == 0)
93 printf("progress %d objects\n", counter);
94 }
95
96 static void handle_object(const unsigned char *sha1)
97 {
98 unsigned long size;
99 enum object_type type;
100 char *buf;
101 struct object *object;
102
103 if (is_null_sha1(sha1))
104 return;
105
106 object = parse_object(sha1);
107 if (!object)
108 die ("Could not read blob %s", sha1_to_hex(sha1));
109
110 if (object->flags & SHOWN)
111 return;
112
113 buf = read_sha1_file(sha1, &type, &size);
114 if (!buf)
115 die ("Could not read blob %s", sha1_to_hex(sha1));
116
117 mark_next_object(object);
118
119 printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
120 if (size && fwrite(buf, size, 1, stdout) != 1)
121 die ("Could not write blob %s", sha1_to_hex(sha1));
122 printf("\n");
123
124 show_progress();
125
126 object->flags |= SHOWN;
127 free(buf);
128 }
129
130 static void show_filemodify(struct diff_queue_struct *q,
131 struct diff_options *options, void *data)
132 {
133 int i;
134 for (i = 0; i < q->nr; i++) {
135 struct diff_filespec *spec = q->queue[i]->two;
136 if (is_null_sha1(spec->sha1))
137 printf("D %s\n", spec->path);
138 else {
139 /*
140 * Links refer to objects in another repositories;
141 * output the SHA-1 verbatim.
142 */
143 if (S_ISGITLINK(spec->mode))
144 printf("M %06o %s %s\n", spec->mode,
145 sha1_to_hex(spec->sha1), spec->path);
146 else {
147 struct object *object = lookup_object(spec->sha1);
148 printf("M %06o :%d %s\n", spec->mode,
149 get_object_mark(object), spec->path);
150 }
151 }
152 }
153 }
154
155 static const char *find_encoding(const char *begin, const char *end)
156 {
157 const char *needle = "\nencoding ";
158 char *bol, *eol;
159
160 bol = memmem(begin, end ? end - begin : strlen(begin),
161 needle, strlen(needle));
162 if (!bol)
163 return git_commit_encoding;
164 bol += strlen(needle);
165 eol = strchrnul(bol, '\n');
166 *eol = '\0';
167 return bol;
168 }
169
170 static void handle_commit(struct commit *commit, struct rev_info *rev)
171 {
172 int saved_output_format = rev->diffopt.output_format;
173 const char *author, *author_end, *committer, *committer_end;
174 const char *encoding, *message;
175 char *reencoded = NULL;
176 struct commit_list *p;
177 int i;
178
179 rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
180
181 parse_commit(commit);
182 author = strstr(commit->buffer, "\nauthor ");
183 if (!author)
184 die ("Could not find author in commit %s",
185 sha1_to_hex(commit->object.sha1));
186 author++;
187 author_end = strchrnul(author, '\n');
188 committer = strstr(author_end, "\ncommitter ");
189 if (!committer)
190 die ("Could not find committer in commit %s",
191 sha1_to_hex(commit->object.sha1));
192 committer++;
193 committer_end = strchrnul(committer, '\n');
194 message = strstr(committer_end, "\n\n");
195 encoding = find_encoding(committer_end, message);
196 if (message)
197 message += 2;
198
199 if (commit->parents) {
200 parse_commit(commit->parents->item);
201 diff_tree_sha1(commit->parents->item->tree->object.sha1,
202 commit->tree->object.sha1, "", &rev->diffopt);
203 }
204 else
205 diff_root_tree_sha1(commit->tree->object.sha1,
206 "", &rev->diffopt);
207
208 /* Export the referenced blobs, and remember the marks. */
209 for (i = 0; i < diff_queued_diff.nr; i++)
210 if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
211 handle_object(diff_queued_diff.queue[i]->two->sha1);
212
213 mark_next_object(&commit->object);
214 if (!is_encoding_utf8(encoding))
215 reencoded = reencode_string(message, "UTF-8", encoding);
216 if (!commit->parents)
217 printf("reset %s\n", (const char*)commit->util);
218 printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
219 (const char *)commit->util, last_idnum,
220 (int)(author_end - author), author,
221 (int)(committer_end - committer), committer,
222 (unsigned)(reencoded
223 ? strlen(reencoded) : message
224 ? strlen(message) : 0),
225 reencoded ? reencoded : message ? message : "");
226 free(reencoded);
227
228 for (i = 0, p = commit->parents; p; p = p->next) {
229 int mark = get_object_mark(&p->item->object);
230 if (!mark)
231 continue;
232 if (i == 0)
233 printf("from :%d\n", mark);
234 else
235 printf("merge :%d\n", mark);
236 i++;
237 }
238
239 log_tree_diff_flush(rev);
240 rev->diffopt.output_format = saved_output_format;
241
242 printf("\n");
243
244 show_progress();
245 }
246
247 static void handle_tail(struct object_array *commits, struct rev_info *revs)
248 {
249 struct commit *commit;
250 while (commits->nr) {
251 commit = (struct commit *)commits->objects[commits->nr - 1].item;
252 if (has_unshown_parent(commit))
253 return;
254 handle_commit(commit, revs);
255 commits->nr--;
256 }
257 }
258
259 static void handle_tag(const char *name, struct tag *tag)
260 {
261 unsigned long size;
262 enum object_type type;
263 char *buf;
264 const char *tagger, *tagger_end, *message;
265 size_t message_size = 0;
266
267 buf = read_sha1_file(tag->object.sha1, &type, &size);
268 if (!buf)
269 die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
270 message = memmem(buf, size, "\n\n", 2);
271 if (message) {
272 message += 2;
273 message_size = strlen(message);
274 }
275 tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
276 if (!tagger)
277 die ("No tagger for tag %s", sha1_to_hex(tag->object.sha1));
278 tagger++;
279 tagger_end = strchrnul(tagger, '\n');
280
281 /* handle signed tags */
282 if (message) {
283 const char *signature = strstr(message,
284 "\n-----BEGIN PGP SIGNATURE-----\n");
285 if (signature)
286 switch(signed_tag_mode) {
287 case ABORT:
288 die ("Encountered signed tag %s; use "
289 "--signed-tag=<mode> to handle it.",
290 sha1_to_hex(tag->object.sha1));
291 case WARN:
292 warning ("Exporting signed tag %s",
293 sha1_to_hex(tag->object.sha1));
294 /* fallthru */
295 case VERBATIM:
296 break;
297 case STRIP:
298 message_size = signature + 1 - message;
299 break;
300 }
301 }
302
303 if (!prefixcmp(name, "refs/tags/"))
304 name += 10;
305 printf("tag %s\nfrom :%d\n%.*s\ndata %d\n%.*s\n",
306 name, get_object_mark(tag->tagged),
307 (int)(tagger_end - tagger), tagger,
308 (int)message_size, (int)message_size, message ? message : "");
309 }
310
311 static void get_tags_and_duplicates(struct object_array *pending,
312 struct path_list *extra_refs)
313 {
314 struct tag *tag;
315 int i;
316
317 for (i = 0; i < pending->nr; i++) {
318 struct object_array_entry *e = pending->objects + i;
319 unsigned char sha1[20];
320 struct commit *commit = commit;
321 char *full_name;
322
323 if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
324 continue;
325
326 switch (e->item->type) {
327 case OBJ_COMMIT:
328 commit = (struct commit *)e->item;
329 break;
330 case OBJ_TAG:
331 tag = (struct tag *)e->item;
332 while (tag && tag->object.type == OBJ_TAG) {
333 path_list_insert(full_name, extra_refs)->util = tag;
334 tag = (struct tag *)tag->tagged;
335 }
336 if (!tag)
337 die ("Tag %s points nowhere?", e->name);
338 switch(tag->object.type) {
339 case OBJ_COMMIT:
340 commit = (struct commit *)tag;
341 break;
342 case OBJ_BLOB:
343 handle_object(tag->object.sha1);
344 continue;
345 }
346 break;
347 default:
348 die ("Unexpected object of type %s",
349 typename(e->item->type));
350 }
351 if (commit->util)
352 /* more than one name for the same object */
353 path_list_insert(full_name, extra_refs)->util = commit;
354 else
355 commit->util = full_name;
356 }
357 }
358
359 static void handle_tags_and_duplicates(struct path_list *extra_refs)
360 {
361 struct commit *commit;
362 int i;
363
364 for (i = extra_refs->nr - 1; i >= 0; i--) {
365 const char *name = extra_refs->items[i].path;
366 struct object *object = extra_refs->items[i].util;
367 switch (object->type) {
368 case OBJ_TAG:
369 handle_tag(name, (struct tag *)object);
370 break;
371 case OBJ_COMMIT:
372 /* create refs pointing to already seen commits */
373 commit = (struct commit *)object;
374 printf("reset %s\nfrom :%d\n\n", name,
375 get_object_mark(&commit->object));
376 show_progress();
377 break;
378 }
379 }
380 }
381
382 static void export_marks(char *file)
383 {
384 unsigned int i;
385 uint32_t mark;
386 struct object_decoration *deco = idnums.hash;
387 FILE *f;
388
389 f = fopen(file, "w");
390 if (!f)
391 error("Unable to open marks file %s for writing", file);
392
393 for (i = 0; i < idnums.size; i++) {
394 if (deco->base && deco->base->type == 1) {
395 mark = ptr_to_mark(deco->decoration);
396 fprintf(f, ":%u %s\n", mark, sha1_to_hex(deco->base->sha1));
397 }
398 deco++;
399 }
400
401 if (ferror(f) || fclose(f))
402 error("Unable to write marks file %s.", file);
403 }
404
405 static void import_marks(char *input_file)
406 {
407 char line[512];
408 FILE *f = fopen(input_file, "r");
409 if (!f)
410 die("cannot read %s: %s", input_file, strerror(errno));
411
412 while (fgets(line, sizeof(line), f)) {
413 uint32_t mark;
414 char *line_end, *mark_end;
415 unsigned char sha1[20];
416 struct object *object;
417
418 line_end = strchr(line, '\n');
419 if (line[0] != ':' || !line_end)
420 die("corrupt mark line: %s", line);
421 *line_end = '\0';
422
423 mark = strtoumax(line + 1, &mark_end, 10);
424 if (!mark || mark_end == line + 1
425 || *mark_end != ' ' || get_sha1(mark_end + 1, sha1))
426 die("corrupt mark line: %s", line);
427
428 object = parse_object(sha1);
429 if (!object)
430 die ("Could not read blob %s", sha1_to_hex(sha1));
431
432 if (object->flags & SHOWN)
433 error("Object %s already has a mark", sha1);
434
435 mark_object(object, mark);
436 if (last_idnum < mark)
437 last_idnum = mark;
438
439 object->flags |= SHOWN;
440 }
441 fclose(f);
442 }
443
444 int cmd_fast_export(int argc, const char **argv, const char *prefix)
445 {
446 struct rev_info revs;
447 struct object_array commits = { 0, 0, NULL };
448 struct path_list extra_refs = { NULL, 0, 0, 0 };
449 struct commit *commit;
450 char *export_filename = NULL, *import_filename = NULL;
451 struct option options[] = {
452 OPT_INTEGER(0, "progress", &progress,
453 "show progress after <n> objects"),
454 OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, "mode",
455 "select handling of signed tags",
456 parse_opt_signed_tag_mode),
457 OPT_STRING(0, "export-marks", &export_filename, "FILE",
458 "Dump marks to this file"),
459 OPT_STRING(0, "import-marks", &import_filename, "FILE",
460 "Import marks from this file"),
461 OPT_END()
462 };
463
464 /* we handle encodings */
465 git_config(git_default_config, NULL);
466
467 init_revisions(&revs, prefix);
468 argc = setup_revisions(argc, argv, &revs, NULL);
469 argc = parse_options(argc, argv, options, fast_export_usage, 0);
470 if (argc > 1)
471 usage_with_options (fast_export_usage, options);
472
473 if (import_filename)
474 import_marks(import_filename);
475
476 get_tags_and_duplicates(&revs.pending, &extra_refs);
477
478 if (prepare_revision_walk(&revs))
479 die("revision walk setup failed");
480 revs.diffopt.format_callback = show_filemodify;
481 DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
482 while ((commit = get_revision(&revs))) {
483 if (has_unshown_parent(commit)) {
484 struct commit_list *parent = commit->parents;
485 add_object_array(&commit->object, NULL, &commits);
486 for (; parent; parent = parent->next)
487 if (!parent->item->util)
488 parent->item->util = commit->util;
489 }
490 else {
491 handle_commit(commit, &revs);
492 handle_tail(&commits, &revs);
493 }
494 }
495
496 handle_tags_and_duplicates(&extra_refs);
497
498 if (export_filename)
499 export_marks(export_filename);
500
501 return 0;
502 }