am: don't infloop for an empty input file
[alt-git.git] / builtin / fast-export.c
blob9836e6b7ca22e254c06d8d766d510ef43a8cbe90
1 /*
2 * "git fast-export" builtin command
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 #include "quote.h"
21 static const char *fast_export_usage[] = {
22 "git fast-export [rev-list-opts]",
23 NULL
26 static int progress;
27 static enum { ABORT, VERBATIM, WARN, STRIP } signed_tag_mode = ABORT;
28 static enum { ERROR, DROP, REWRITE } tag_of_filtered_mode = ABORT;
29 static int fake_missing_tagger;
30 static int use_done_feature;
31 static int no_data;
32 static int full_tree;
34 static int parse_opt_signed_tag_mode(const struct option *opt,
35 const char *arg, int unset)
37 if (unset || !strcmp(arg, "abort"))
38 signed_tag_mode = ABORT;
39 else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
40 signed_tag_mode = VERBATIM;
41 else if (!strcmp(arg, "warn"))
42 signed_tag_mode = WARN;
43 else if (!strcmp(arg, "strip"))
44 signed_tag_mode = STRIP;
45 else
46 return error("Unknown signed-tag mode: %s", arg);
47 return 0;
50 static int parse_opt_tag_of_filtered_mode(const struct option *opt,
51 const char *arg, int unset)
53 if (unset || !strcmp(arg, "abort"))
54 tag_of_filtered_mode = ABORT;
55 else if (!strcmp(arg, "drop"))
56 tag_of_filtered_mode = DROP;
57 else if (!strcmp(arg, "rewrite"))
58 tag_of_filtered_mode = REWRITE;
59 else
60 return error("Unknown tag-of-filtered mode: %s", arg);
61 return 0;
64 static struct decoration idnums;
65 static uint32_t last_idnum;
67 static int has_unshown_parent(struct commit *commit)
69 struct commit_list *parent;
71 for (parent = commit->parents; parent; parent = parent->next)
72 if (!(parent->item->object.flags & SHOWN) &&
73 !(parent->item->object.flags & UNINTERESTING))
74 return 1;
75 return 0;
78 /* Since intptr_t is C99, we do not use it here */
79 static inline uint32_t *mark_to_ptr(uint32_t mark)
81 return ((uint32_t *)NULL) + mark;
84 static inline uint32_t ptr_to_mark(void * mark)
86 return (uint32_t *)mark - (uint32_t *)NULL;
89 static inline void mark_object(struct object *object, uint32_t mark)
91 add_decoration(&idnums, object, mark_to_ptr(mark));
94 static inline void mark_next_object(struct object *object)
96 mark_object(object, ++last_idnum);
99 static int get_object_mark(struct object *object)
101 void *decoration = lookup_decoration(&idnums, object);
102 if (!decoration)
103 return 0;
104 return ptr_to_mark(decoration);
107 static void show_progress(void)
109 static int counter = 0;
110 if (!progress)
111 return;
112 if ((++counter % progress) == 0)
113 printf("progress %d objects\n", counter);
116 static void handle_object(const unsigned char *sha1)
118 unsigned long size;
119 enum object_type type;
120 char *buf;
121 struct object *object;
123 if (no_data)
124 return;
126 if (is_null_sha1(sha1))
127 return;
129 object = parse_object(sha1);
130 if (!object)
131 die ("Could not read blob %s", sha1_to_hex(sha1));
133 if (object->flags & SHOWN)
134 return;
136 buf = read_sha1_file(sha1, &type, &size);
137 if (!buf)
138 die ("Could not read blob %s", sha1_to_hex(sha1));
140 mark_next_object(object);
142 printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
143 if (size && fwrite(buf, size, 1, stdout) != 1)
144 die_errno ("Could not write blob '%s'", sha1_to_hex(sha1));
145 printf("\n");
147 show_progress();
149 object->flags |= SHOWN;
150 free(buf);
153 static int depth_first(const void *a_, const void *b_)
155 const struct diff_filepair *a = *((const struct diff_filepair **)a_);
156 const struct diff_filepair *b = *((const struct diff_filepair **)b_);
157 const char *name_a, *name_b;
158 int len_a, len_b, len;
159 int cmp;
161 name_a = a->one ? a->one->path : a->two->path;
162 name_b = b->one ? b->one->path : b->two->path;
164 len_a = strlen(name_a);
165 len_b = strlen(name_b);
166 len = (len_a < len_b) ? len_a : len_b;
168 /* strcmp will sort 'd' before 'd/e', we want 'd/e' before 'd' */
169 cmp = memcmp(name_a, name_b, len);
170 if (cmp)
171 return cmp;
172 cmp = len_b - len_a;
173 if (cmp)
174 return cmp;
176 * Move 'R'ename entries last so that all references of the file
177 * appear in the output before it is renamed (e.g., when a file
178 * was copied and renamed in the same commit).
180 return (a->status == 'R') - (b->status == 'R');
183 static void print_path(const char *path)
185 int need_quote = quote_c_style(path, NULL, NULL, 0);
186 if (need_quote)
187 quote_c_style(path, NULL, stdout, 0);
188 else
189 printf("%s", path);
192 static void show_filemodify(struct diff_queue_struct *q,
193 struct diff_options *options, void *data)
195 int i;
198 * Handle files below a directory first, in case they are all deleted
199 * and the directory changes to a file or symlink.
201 qsort(q->queue, q->nr, sizeof(q->queue[0]), depth_first);
203 for (i = 0; i < q->nr; i++) {
204 struct diff_filespec *ospec = q->queue[i]->one;
205 struct diff_filespec *spec = q->queue[i]->two;
207 switch (q->queue[i]->status) {
208 case DIFF_STATUS_DELETED:
209 printf("D ");
210 print_path(spec->path);
211 putchar('\n');
212 break;
214 case DIFF_STATUS_COPIED:
215 case DIFF_STATUS_RENAMED:
216 printf("%c ", q->queue[i]->status);
217 print_path(ospec->path);
218 putchar(' ');
219 print_path(spec->path);
220 putchar('\n');
222 if (!hashcmp(ospec->sha1, spec->sha1) &&
223 ospec->mode == spec->mode)
224 break;
225 /* fallthrough */
227 case DIFF_STATUS_TYPE_CHANGED:
228 case DIFF_STATUS_MODIFIED:
229 case DIFF_STATUS_ADDED:
231 * Links refer to objects in another repositories;
232 * output the SHA-1 verbatim.
234 if (no_data || S_ISGITLINK(spec->mode))
235 printf("M %06o %s ", spec->mode,
236 sha1_to_hex(spec->sha1));
237 else {
238 struct object *object = lookup_object(spec->sha1);
239 printf("M %06o :%d ", spec->mode,
240 get_object_mark(object));
242 print_path(spec->path);
243 putchar('\n');
244 break;
246 default:
247 die("Unexpected comparison status '%c' for %s, %s",
248 q->queue[i]->status,
249 ospec->path ? ospec->path : "none",
250 spec->path ? spec->path : "none");
255 static const char *find_encoding(const char *begin, const char *end)
257 const char *needle = "\nencoding ";
258 char *bol, *eol;
260 bol = memmem(begin, end ? end - begin : strlen(begin),
261 needle, strlen(needle));
262 if (!bol)
263 return git_commit_encoding;
264 bol += strlen(needle);
265 eol = strchrnul(bol, '\n');
266 *eol = '\0';
267 return bol;
270 static void handle_commit(struct commit *commit, struct rev_info *rev)
272 int saved_output_format = rev->diffopt.output_format;
273 const char *author, *author_end, *committer, *committer_end;
274 const char *encoding, *message;
275 char *reencoded = NULL;
276 struct commit_list *p;
277 int i;
279 rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
281 parse_commit(commit);
282 author = strstr(commit->buffer, "\nauthor ");
283 if (!author)
284 die ("Could not find author in commit %s",
285 sha1_to_hex(commit->object.sha1));
286 author++;
287 author_end = strchrnul(author, '\n');
288 committer = strstr(author_end, "\ncommitter ");
289 if (!committer)
290 die ("Could not find committer in commit %s",
291 sha1_to_hex(commit->object.sha1));
292 committer++;
293 committer_end = strchrnul(committer, '\n');
294 message = strstr(committer_end, "\n\n");
295 encoding = find_encoding(committer_end, message);
296 if (message)
297 message += 2;
299 if (commit->parents &&
300 get_object_mark(&commit->parents->item->object) != 0 &&
301 !full_tree) {
302 parse_commit(commit->parents->item);
303 diff_tree_sha1(commit->parents->item->tree->object.sha1,
304 commit->tree->object.sha1, "", &rev->diffopt);
306 else
307 diff_root_tree_sha1(commit->tree->object.sha1,
308 "", &rev->diffopt);
310 /* Export the referenced blobs, and remember the marks. */
311 for (i = 0; i < diff_queued_diff.nr; i++)
312 if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
313 handle_object(diff_queued_diff.queue[i]->two->sha1);
315 mark_next_object(&commit->object);
316 if (!is_encoding_utf8(encoding))
317 reencoded = reencode_string(message, "UTF-8", encoding);
318 if (!commit->parents)
319 printf("reset %s\n", (const char*)commit->util);
320 printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
321 (const char *)commit->util, last_idnum,
322 (int)(author_end - author), author,
323 (int)(committer_end - committer), committer,
324 (unsigned)(reencoded
325 ? strlen(reencoded) : message
326 ? strlen(message) : 0),
327 reencoded ? reencoded : message ? message : "");
328 free(reencoded);
330 for (i = 0, p = commit->parents; p; p = p->next) {
331 int mark = get_object_mark(&p->item->object);
332 if (!mark)
333 continue;
334 if (i == 0)
335 printf("from :%d\n", mark);
336 else
337 printf("merge :%d\n", mark);
338 i++;
341 if (full_tree)
342 printf("deleteall\n");
343 log_tree_diff_flush(rev);
344 rev->diffopt.output_format = saved_output_format;
346 printf("\n");
348 show_progress();
351 static void handle_tail(struct object_array *commits, struct rev_info *revs)
353 struct commit *commit;
354 while (commits->nr) {
355 commit = (struct commit *)commits->objects[commits->nr - 1].item;
356 if (has_unshown_parent(commit))
357 return;
358 handle_commit(commit, revs);
359 commits->nr--;
363 static void handle_tag(const char *name, struct tag *tag)
365 unsigned long size;
366 enum object_type type;
367 char *buf;
368 const char *tagger, *tagger_end, *message;
369 size_t message_size = 0;
370 struct object *tagged;
371 int tagged_mark;
372 struct commit *p;
374 /* Trees have no identifer in fast-export output, thus we have no way
375 * to output tags of trees, tags of tags of trees, etc. Simply omit
376 * such tags.
378 tagged = tag->tagged;
379 while (tagged->type == OBJ_TAG) {
380 tagged = ((struct tag *)tagged)->tagged;
382 if (tagged->type == OBJ_TREE) {
383 warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
384 sha1_to_hex(tag->object.sha1));
385 return;
388 buf = read_sha1_file(tag->object.sha1, &type, &size);
389 if (!buf)
390 die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
391 message = memmem(buf, size, "\n\n", 2);
392 if (message) {
393 message += 2;
394 message_size = strlen(message);
396 tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
397 if (!tagger) {
398 if (fake_missing_tagger)
399 tagger = "tagger Unspecified Tagger "
400 "<unspecified-tagger> 0 +0000";
401 else
402 tagger = "";
403 tagger_end = tagger + strlen(tagger);
404 } else {
405 tagger++;
406 tagger_end = strchrnul(tagger, '\n');
409 /* handle signed tags */
410 if (message) {
411 const char *signature = strstr(message,
412 "\n-----BEGIN PGP SIGNATURE-----\n");
413 if (signature)
414 switch(signed_tag_mode) {
415 case ABORT:
416 die ("Encountered signed tag %s; use "
417 "--signed-tag=<mode> to handle it.",
418 sha1_to_hex(tag->object.sha1));
419 case WARN:
420 warning ("Exporting signed tag %s",
421 sha1_to_hex(tag->object.sha1));
422 /* fallthru */
423 case VERBATIM:
424 break;
425 case STRIP:
426 message_size = signature + 1 - message;
427 break;
431 /* handle tag->tagged having been filtered out due to paths specified */
432 tagged = tag->tagged;
433 tagged_mark = get_object_mark(tagged);
434 if (!tagged_mark) {
435 switch(tag_of_filtered_mode) {
436 case ABORT:
437 die ("Tag %s tags unexported object; use "
438 "--tag-of-filtered-object=<mode> to handle it.",
439 sha1_to_hex(tag->object.sha1));
440 case DROP:
441 /* Ignore this tag altogether */
442 return;
443 case REWRITE:
444 if (tagged->type != OBJ_COMMIT) {
445 die ("Tag %s tags unexported %s!",
446 sha1_to_hex(tag->object.sha1),
447 typename(tagged->type));
449 p = (struct commit *)tagged;
450 for (;;) {
451 if (p->parents && p->parents->next)
452 break;
453 if (p->object.flags & UNINTERESTING)
454 break;
455 if (!(p->object.flags & TREESAME))
456 break;
457 if (!p->parents)
458 die ("Can't find replacement commit for tag %s\n",
459 sha1_to_hex(tag->object.sha1));
460 p = p->parents->item;
462 tagged_mark = get_object_mark(&p->object);
466 if (!prefixcmp(name, "refs/tags/"))
467 name += 10;
468 printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
469 name, tagged_mark,
470 (int)(tagger_end - tagger), tagger,
471 tagger == tagger_end ? "" : "\n",
472 (int)message_size, (int)message_size, message ? message : "");
475 static void get_tags_and_duplicates(struct object_array *pending,
476 struct string_list *extra_refs)
478 struct tag *tag;
479 int i;
481 for (i = 0; i < pending->nr; i++) {
482 struct object_array_entry *e = pending->objects + i;
483 unsigned char sha1[20];
484 struct commit *commit = commit;
485 char *full_name;
487 if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
488 continue;
490 switch (e->item->type) {
491 case OBJ_COMMIT:
492 commit = (struct commit *)e->item;
493 break;
494 case OBJ_TAG:
495 tag = (struct tag *)e->item;
497 /* handle nested tags */
498 while (tag && tag->object.type == OBJ_TAG) {
499 parse_object(tag->object.sha1);
500 string_list_append(extra_refs, full_name)->util = tag;
501 tag = (struct tag *)tag->tagged;
503 if (!tag)
504 die ("Tag %s points nowhere?", e->name);
505 switch(tag->object.type) {
506 case OBJ_COMMIT:
507 commit = (struct commit *)tag;
508 break;
509 case OBJ_BLOB:
510 handle_object(tag->object.sha1);
511 continue;
512 default: /* OBJ_TAG (nested tags) is already handled */
513 warning("Tag points to object of unexpected type %s, skipping.",
514 typename(tag->object.type));
515 continue;
517 break;
518 default:
519 warning("%s: Unexpected object of type %s, skipping.",
520 e->name,
521 typename(e->item->type));
522 continue;
524 if (commit->util)
525 /* more than one name for the same object */
526 string_list_append(extra_refs, full_name)->util = commit;
527 else
528 commit->util = full_name;
532 static void handle_tags_and_duplicates(struct string_list *extra_refs)
534 struct commit *commit;
535 int i;
537 for (i = extra_refs->nr - 1; i >= 0; i--) {
538 const char *name = extra_refs->items[i].string;
539 struct object *object = extra_refs->items[i].util;
540 switch (object->type) {
541 case OBJ_TAG:
542 handle_tag(name, (struct tag *)object);
543 break;
544 case OBJ_COMMIT:
545 /* create refs pointing to already seen commits */
546 commit = (struct commit *)object;
547 printf("reset %s\nfrom :%d\n\n", name,
548 get_object_mark(&commit->object));
549 show_progress();
550 break;
555 static void export_marks(char *file)
557 unsigned int i;
558 uint32_t mark;
559 struct object_decoration *deco = idnums.hash;
560 FILE *f;
561 int e = 0;
563 f = fopen(file, "w");
564 if (!f)
565 die_errno("Unable to open marks file %s for writing.", file);
567 for (i = 0; i < idnums.size; i++) {
568 if (deco->base && deco->base->type == 1) {
569 mark = ptr_to_mark(deco->decoration);
570 if (fprintf(f, ":%"PRIu32" %s\n", mark,
571 sha1_to_hex(deco->base->sha1)) < 0) {
572 e = 1;
573 break;
576 deco++;
579 e |= ferror(f);
580 e |= fclose(f);
581 if (e)
582 error("Unable to write marks file %s.", file);
585 static void import_marks(char *input_file)
587 char line[512];
588 FILE *f = fopen(input_file, "r");
589 if (!f)
590 die_errno("cannot read '%s'", input_file);
592 while (fgets(line, sizeof(line), f)) {
593 uint32_t mark;
594 char *line_end, *mark_end;
595 unsigned char sha1[20];
596 struct object *object;
598 line_end = strchr(line, '\n');
599 if (line[0] != ':' || !line_end)
600 die("corrupt mark line: %s", line);
601 *line_end = '\0';
603 mark = strtoumax(line + 1, &mark_end, 10);
604 if (!mark || mark_end == line + 1
605 || *mark_end != ' ' || get_sha1(mark_end + 1, sha1))
606 die("corrupt mark line: %s", line);
608 object = parse_object(sha1);
609 if (!object)
610 die ("Could not read blob %s", sha1_to_hex(sha1));
612 if (object->flags & SHOWN)
613 error("Object %s already has a mark", sha1);
615 mark_object(object, mark);
616 if (last_idnum < mark)
617 last_idnum = mark;
619 object->flags |= SHOWN;
621 fclose(f);
624 int cmd_fast_export(int argc, const char **argv, const char *prefix)
626 struct rev_info revs;
627 struct object_array commits = OBJECT_ARRAY_INIT;
628 struct string_list extra_refs = STRING_LIST_INIT_NODUP;
629 struct commit *commit;
630 char *export_filename = NULL, *import_filename = NULL;
631 struct option options[] = {
632 OPT_INTEGER(0, "progress", &progress,
633 "show progress after <n> objects"),
634 OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, "mode",
635 "select handling of signed tags",
636 parse_opt_signed_tag_mode),
637 OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, "mode",
638 "select handling of tags that tag filtered objects",
639 parse_opt_tag_of_filtered_mode),
640 OPT_STRING(0, "export-marks", &export_filename, "file",
641 "Dump marks to this file"),
642 OPT_STRING(0, "import-marks", &import_filename, "file",
643 "Import marks from this file"),
644 OPT_BOOLEAN(0, "fake-missing-tagger", &fake_missing_tagger,
645 "Fake a tagger when tags lack one"),
646 OPT_BOOLEAN(0, "full-tree", &full_tree,
647 "Output full tree for each commit"),
648 OPT_BOOLEAN(0, "use-done-feature", &use_done_feature,
649 "Use the done feature to terminate the stream"),
650 { OPTION_NEGBIT, 0, "data", &no_data, NULL,
651 "Skip output of blob data",
652 PARSE_OPT_NOARG | PARSE_OPT_NEGHELP, NULL, 1 },
653 OPT_END()
656 if (argc == 1)
657 usage_with_options (fast_export_usage, options);
659 /* we handle encodings */
660 git_config(git_default_config, NULL);
662 init_revisions(&revs, prefix);
663 revs.topo_order = 1;
664 revs.show_source = 1;
665 revs.rewrite_parents = 1;
666 argc = setup_revisions(argc, argv, &revs, NULL);
667 argc = parse_options(argc, argv, prefix, options, fast_export_usage, 0);
668 if (argc > 1)
669 usage_with_options (fast_export_usage, options);
671 if (use_done_feature)
672 printf("feature done\n");
674 if (import_filename)
675 import_marks(import_filename);
677 if (import_filename && revs.prune_data.nr)
678 full_tree = 1;
680 get_tags_and_duplicates(&revs.pending, &extra_refs);
682 if (prepare_revision_walk(&revs))
683 die("revision walk setup failed");
684 revs.diffopt.format_callback = show_filemodify;
685 DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
686 while ((commit = get_revision(&revs))) {
687 if (has_unshown_parent(commit)) {
688 add_object_array(&commit->object, NULL, &commits);
690 else {
691 handle_commit(commit, &revs);
692 handle_tail(&commits, &revs);
696 handle_tags_and_duplicates(&extra_refs);
698 if (export_filename)
699 export_marks(export_filename);
701 if (use_done_feature)
702 printf("done\n");
704 return 0;