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 "string-list.h"
17#include "utf8.h"
18#include "parse-options.h"
19
20static const char *fast_export_usage[] = {
21 "git fast-export [rev-list-opts]",
22 NULL
23};
24
25static int progress;
26static enum { VERBATIM, WARN, STRIP, ABORT } signed_tag_mode = ABORT;
27static int fake_missing_tagger;
28
29static int parse_opt_signed_tag_mode(const struct option *opt,
30 const char *arg, int unset)
31{
32 if (unset || !strcmp(arg, "abort"))
33 signed_tag_mode = ABORT;
34 else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
35 signed_tag_mode = VERBATIM;
36 else if (!strcmp(arg, "warn"))
37 signed_tag_mode = WARN;
38 else if (!strcmp(arg, "strip"))
39 signed_tag_mode = STRIP;
40 else
41 return error("Unknown signed-tag mode: %s", arg);
42 return 0;
43}
44
45static struct decoration idnums;
46static uint32_t last_idnum;
47
48static int has_unshown_parent(struct commit *commit)
49{
50 struct commit_list *parent;
51
52 for (parent = commit->parents; parent; parent = parent->next)
53 if (!(parent->item->object.flags & SHOWN) &&
54 !(parent->item->object.flags & UNINTERESTING))
55 return 1;
56 return 0;
57}
58
59/* Since intptr_t is C99, we do not use it here */
60static inline uint32_t *mark_to_ptr(uint32_t mark)
61{
62 return ((uint32_t *)NULL) + mark;
63}
64
65static inline uint32_t ptr_to_mark(void * mark)
66{
67 return (uint32_t *)mark - (uint32_t *)NULL;
68}
69
70static inline void mark_object(struct object *object, uint32_t mark)
71{
72 add_decoration(&idnums, object, mark_to_ptr(mark));
73}
74
75static inline void mark_next_object(struct object *object)
76{
77 mark_object(object, ++last_idnum);
78}
79
80static int get_object_mark(struct object *object)
81{
82 void *decoration = lookup_decoration(&idnums, object);
83 if (!decoration)
84 return 0;
85 return ptr_to_mark(decoration);
86}
87
88static void show_progress(void)
89{
90 static int counter = 0;
91 if (!progress)
92 return;
93 if ((++counter % progress) == 0)
94 printf("progress %d objects\n", counter);
95}
96
97static void handle_object(const unsigned char *sha1)
98{
99 unsigned long size;
100 enum object_type type;
101 char *buf;
102 struct object *object;
103
104 if (is_null_sha1(sha1))
105 return;
106
107 object = parse_object(sha1);
108 if (!object)
109 die ("Could not read blob %s", sha1_to_hex(sha1));
110
111 if (object->flags & SHOWN)
112 return;
113
114 buf = read_sha1_file(sha1, &type, &size);
115 if (!buf)
116 die ("Could not read blob %s", sha1_to_hex(sha1));
117
118 mark_next_object(object);
119
120 printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
121 if (size && fwrite(buf, size, 1, stdout) != 1)
122 die ("Could not write blob %s", sha1_to_hex(sha1));
123 printf("\n");
124
125 show_progress();
126
127 object->flags |= SHOWN;
128 free(buf);
129}
130
131static void show_filemodify(struct diff_queue_struct *q,
132 struct diff_options *options, void *data)
133{
134 int i;
135 for (i = 0; i < q->nr; i++) {
136 struct diff_filespec *ospec = q->queue[i]->one;
137 struct diff_filespec *spec = q->queue[i]->two;
138
139 switch (q->queue[i]->status) {
140 case DIFF_STATUS_DELETED:
141 printf("D %s\n", spec->path);
142 break;
143
144 case DIFF_STATUS_COPIED:
145 case DIFF_STATUS_RENAMED:
146 printf("%c \"%s\" \"%s\"\n", q->queue[i]->status,
147 ospec->path, spec->path);
148
149 if (!hashcmp(ospec->sha1, spec->sha1) &&
150 ospec->mode == spec->mode)
151 break;
152 /* fallthrough */
153
154 case DIFF_STATUS_TYPE_CHANGED:
155 case DIFF_STATUS_MODIFIED:
156 case DIFF_STATUS_ADDED:
157 /*
158 * Links refer to objects in another repositories;
159 * output the SHA-1 verbatim.
160 */
161 if (S_ISGITLINK(spec->mode))
162 printf("M %06o %s %s\n", spec->mode,
163 sha1_to_hex(spec->sha1), spec->path);
164 else {
165 struct object *object = lookup_object(spec->sha1);
166 printf("M %06o :%d %s\n", spec->mode,
167 get_object_mark(object), spec->path);
168 }
169 break;
170
171 default:
172 die("Unexpected comparison status '%c' for %s, %s",
173 q->queue[i]->status,
174 ospec->path ? ospec->path : "none",
175 spec->path ? spec->path : "none");
176 }
177 }
178}
179
180static const char *find_encoding(const char *begin, const char *end)
181{
182 const char *needle = "\nencoding ";
183 char *bol, *eol;
184
185 bol = memmem(begin, end ? end - begin : strlen(begin),
186 needle, strlen(needle));
187 if (!bol)
188 return git_commit_encoding;
189 bol += strlen(needle);
190 eol = strchrnul(bol, '\n');
191 *eol = '\0';
192 return bol;
193}
194
195static void handle_commit(struct commit *commit, struct rev_info *rev)
196{
197 int saved_output_format = rev->diffopt.output_format;
198 const char *author, *author_end, *committer, *committer_end;
199 const char *encoding, *message;
200 char *reencoded = NULL;
201 struct commit_list *p;
202 int i;
203
204 rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
205
206 parse_commit(commit);
207 author = strstr(commit->buffer, "\nauthor ");
208 if (!author)
209 die ("Could not find author in commit %s",
210 sha1_to_hex(commit->object.sha1));
211 author++;
212 author_end = strchrnul(author, '\n');
213 committer = strstr(author_end, "\ncommitter ");
214 if (!committer)
215 die ("Could not find committer in commit %s",
216 sha1_to_hex(commit->object.sha1));
217 committer++;
218 committer_end = strchrnul(committer, '\n');
219 message = strstr(committer_end, "\n\n");
220 encoding = find_encoding(committer_end, message);
221 if (message)
222 message += 2;
223
224 if (commit->parents &&
225 get_object_mark(&commit->parents->item->object) != 0) {
226 parse_commit(commit->parents->item);
227 diff_tree_sha1(commit->parents->item->tree->object.sha1,
228 commit->tree->object.sha1, "", &rev->diffopt);
229 }
230 else
231 diff_root_tree_sha1(commit->tree->object.sha1,
232 "", &rev->diffopt);
233
234 /* Export the referenced blobs, and remember the marks. */
235 for (i = 0; i < diff_queued_diff.nr; i++)
236 if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
237 handle_object(diff_queued_diff.queue[i]->two->sha1);
238
239 mark_next_object(&commit->object);
240 if (!is_encoding_utf8(encoding))
241 reencoded = reencode_string(message, "UTF-8", encoding);
242 if (!commit->parents)
243 printf("reset %s\n", (const char*)commit->util);
244 printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
245 (const char *)commit->util, last_idnum,
246 (int)(author_end - author), author,
247 (int)(committer_end - committer), committer,
248 (unsigned)(reencoded
249 ? strlen(reencoded) : message
250 ? strlen(message) : 0),
251 reencoded ? reencoded : message ? message : "");
252 free(reencoded);
253
254 for (i = 0, p = commit->parents; p; p = p->next) {
255 int mark = get_object_mark(&p->item->object);
256 if (!mark)
257 continue;
258 if (i == 0)
259 printf("from :%d\n", mark);
260 else
261 printf("merge :%d\n", mark);
262 i++;
263 }
264
265 log_tree_diff_flush(rev);
266 rev->diffopt.output_format = saved_output_format;
267
268 printf("\n");
269
270 show_progress();
271}
272
273static void handle_tail(struct object_array *commits, struct rev_info *revs)
274{
275 struct commit *commit;
276 while (commits->nr) {
277 commit = (struct commit *)commits->objects[commits->nr - 1].item;
278 if (has_unshown_parent(commit))
279 return;
280 handle_commit(commit, revs);
281 commits->nr--;
282 }
283}
284
285static void handle_tag(const char *name, struct tag *tag)
286{
287 unsigned long size;
288 enum object_type type;
289 char *buf;
290 const char *tagger, *tagger_end, *message;
291 size_t message_size = 0;
292
293 buf = read_sha1_file(tag->object.sha1, &type, &size);
294 if (!buf)
295 die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
296 message = memmem(buf, size, "\n\n", 2);
297 if (message) {
298 message += 2;
299 message_size = strlen(message);
300 }
301 tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
302 if (!tagger) {
303 if (fake_missing_tagger)
304 tagger = "tagger Unspecified Tagger "
305 "<unspecified-tagger> 0 +0000";
306 else
307 tagger = "";
308 tagger_end = tagger + strlen(tagger);
309 } else {
310 tagger++;
311 tagger_end = strchrnul(tagger, '\n');
312 }
313
314 /* handle signed tags */
315 if (message) {
316 const char *signature = strstr(message,
317 "\n-----BEGIN PGP SIGNATURE-----\n");
318 if (signature)
319 switch(signed_tag_mode) {
320 case ABORT:
321 die ("Encountered signed tag %s; use "
322 "--signed-tag=<mode> to handle it.",
323 sha1_to_hex(tag->object.sha1));
324 case WARN:
325 warning ("Exporting signed tag %s",
326 sha1_to_hex(tag->object.sha1));
327 /* fallthru */
328 case VERBATIM:
329 break;
330 case STRIP:
331 message_size = signature + 1 - message;
332 break;
333 }
334 }
335
336 if (!prefixcmp(name, "refs/tags/"))
337 name += 10;
338 printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
339 name, get_object_mark(tag->tagged),
340 (int)(tagger_end - tagger), tagger,
341 tagger == tagger_end ? "" : "\n",
342 (int)message_size, (int)message_size, message ? message : "");
343}
344
345static void get_tags_and_duplicates(struct object_array *pending,
346 struct string_list *extra_refs)
347{
348 struct tag *tag;
349 int i;
350
351 for (i = 0; i < pending->nr; i++) {
352 struct object_array_entry *e = pending->objects + i;
353 unsigned char sha1[20];
354 struct commit *commit = commit;
355 char *full_name;
356
357 if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
358 continue;
359
360 switch (e->item->type) {
361 case OBJ_COMMIT:
362 commit = (struct commit *)e->item;
363 break;
364 case OBJ_TAG:
365 tag = (struct tag *)e->item;
366 while (tag && tag->object.type == OBJ_TAG) {
367 string_list_append(full_name, extra_refs)->util = tag;
368 tag = (struct tag *)tag->tagged;
369 }
370 if (!tag)
371 die ("Tag %s points nowhere?", e->name);
372 switch(tag->object.type) {
373 case OBJ_COMMIT:
374 commit = (struct commit *)tag;
375 break;
376 case OBJ_BLOB:
377 handle_object(tag->object.sha1);
378 continue;
379 }
380 break;
381 default:
382 die ("Unexpected object of type %s",
383 typename(e->item->type));
384 }
385 if (commit->util)
386 /* more than one name for the same object */
387 string_list_append(full_name, extra_refs)->util = commit;
388 else
389 commit->util = full_name;
390 }
391}
392
393static void handle_tags_and_duplicates(struct string_list *extra_refs)
394{
395 struct commit *commit;
396 int i;
397
398 for (i = extra_refs->nr - 1; i >= 0; i--) {
399 const char *name = extra_refs->items[i].string;
400 struct object *object = extra_refs->items[i].util;
401 switch (object->type) {
402 case OBJ_TAG:
403 handle_tag(name, (struct tag *)object);
404 break;
405 case OBJ_COMMIT:
406 /* create refs pointing to already seen commits */
407 commit = (struct commit *)object;
408 printf("reset %s\nfrom :%d\n\n", name,
409 get_object_mark(&commit->object));
410 show_progress();
411 break;
412 }
413 }
414}
415
416static void export_marks(char *file)
417{
418 unsigned int i;
419 uint32_t mark;
420 struct object_decoration *deco = idnums.hash;
421 FILE *f;
422
423 f = fopen(file, "w");
424 if (!f)
425 error("Unable to open marks file %s for writing", file);
426
427 for (i = 0; i < idnums.size; i++) {
428 if (deco->base && deco->base->type == 1) {
429 mark = ptr_to_mark(deco->decoration);
430 fprintf(f, ":%"PRIu32" %s\n", mark,
431 sha1_to_hex(deco->base->sha1));
432 }
433 deco++;
434 }
435
436 if (ferror(f) || fclose(f))
437 error("Unable to write marks file %s.", file);
438}
439
440static void import_marks(char *input_file)
441{
442 char line[512];
443 FILE *f = fopen(input_file, "r");
444 if (!f)
445 die("cannot read %s: %s", input_file, strerror(errno));
446
447 while (fgets(line, sizeof(line), f)) {
448 uint32_t mark;
449 char *line_end, *mark_end;
450 unsigned char sha1[20];
451 struct object *object;
452
453 line_end = strchr(line, '\n');
454 if (line[0] != ':' || !line_end)
455 die("corrupt mark line: %s", line);
456 *line_end = '\0';
457
458 mark = strtoumax(line + 1, &mark_end, 10);
459 if (!mark || mark_end == line + 1
460 || *mark_end != ' ' || get_sha1(mark_end + 1, sha1))
461 die("corrupt mark line: %s", line);
462
463 object = parse_object(sha1);
464 if (!object)
465 die ("Could not read blob %s", sha1_to_hex(sha1));
466
467 if (object->flags & SHOWN)
468 error("Object %s already has a mark", sha1);
469
470 mark_object(object, mark);
471 if (last_idnum < mark)
472 last_idnum = mark;
473
474 object->flags |= SHOWN;
475 }
476 fclose(f);
477}
478
479int cmd_fast_export(int argc, const char **argv, const char *prefix)
480{
481 struct rev_info revs;
482 struct object_array commits = { 0, 0, NULL };
483 struct string_list extra_refs = { NULL, 0, 0, 0 };
484 struct commit *commit;
485 char *export_filename = NULL, *import_filename = NULL;
486 struct option options[] = {
487 OPT_INTEGER(0, "progress", &progress,
488 "show progress after <n> objects"),
489 OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, "mode",
490 "select handling of signed tags",
491 parse_opt_signed_tag_mode),
492 OPT_STRING(0, "export-marks", &export_filename, "FILE",
493 "Dump marks to this file"),
494 OPT_STRING(0, "import-marks", &import_filename, "FILE",
495 "Import marks from this file"),
496 OPT_BOOLEAN(0, "fake-missing-tagger", &fake_missing_tagger,
497 "Fake a tagger when tags lack one"),
498 OPT_END()
499 };
500
501 if (argc == 1)
502 usage_with_options (fast_export_usage, options);
503
504 /* we handle encodings */
505 git_config(git_default_config, NULL);
506
507 init_revisions(&revs, prefix);
508 argc = setup_revisions(argc, argv, &revs, NULL);
509 argc = parse_options(argc, argv, options, fast_export_usage, 0);
510 if (argc > 1)
511 usage_with_options (fast_export_usage, options);
512
513 if (import_filename)
514 import_marks(import_filename);
515
516 get_tags_and_duplicates(&revs.pending, &extra_refs);
517
518 revs.topo_order = 1;
519 if (prepare_revision_walk(&revs))
520 die("revision walk setup failed");
521 revs.diffopt.format_callback = show_filemodify;
522 DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
523 while ((commit = get_revision(&revs))) {
524 if (has_unshown_parent(commit)) {
525 struct commit_list *parent = commit->parents;
526 add_object_array(&commit->object, NULL, &commits);
527 for (; parent; parent = parent->next)
528 if (!parent->item->util)
529 parent->item->util = commit->util;
530 }
531 else {
532 handle_commit(commit, &revs);
533 handle_tail(&commits, &revs);
534 }
535 }
536
537 handle_tags_and_duplicates(&extra_refs);
538
539 if (export_filename)
540 export_marks(export_filename);
541
542 return 0;
543}