Merge branch 'ms/reflog-show-is-default' into maint
[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 "string-list.h"
17 #include "utf8.h"
18 #include "parse-options.h"
19 #include "quote.h"
20
21 static const char *fast_export_usage[] = {
22         "git fast-export [rev-list-opts]",
23         NULL
24 };
25
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 no_data;
31 static int full_tree;
32
33 static int parse_opt_signed_tag_mode(const struct option *opt,
34                                      const char *arg, int unset)
35 {
36         if (unset || !strcmp(arg, "abort"))
37                 signed_tag_mode = ABORT;
38         else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
39                 signed_tag_mode = VERBATIM;
40         else if (!strcmp(arg, "warn"))
41                 signed_tag_mode = WARN;
42         else if (!strcmp(arg, "strip"))
43                 signed_tag_mode = STRIP;
44         else
45                 return error("Unknown signed-tag mode: %s", arg);
46         return 0;
47 }
48
49 static int parse_opt_tag_of_filtered_mode(const struct option *opt,
50                                           const char *arg, int unset)
51 {
52         if (unset || !strcmp(arg, "abort"))
53                 tag_of_filtered_mode = ABORT;
54         else if (!strcmp(arg, "drop"))
55                 tag_of_filtered_mode = DROP;
56         else if (!strcmp(arg, "rewrite"))
57                 tag_of_filtered_mode = REWRITE;
58         else
59                 return error("Unknown tag-of-filtered mode: %s", arg);
60         return 0;
61 }
62
63 static struct decoration idnums;
64 static uint32_t last_idnum;
65
66 static int has_unshown_parent(struct commit *commit)
67 {
68         struct commit_list *parent;
69
70         for (parent = commit->parents; parent; parent = parent->next)
71                 if (!(parent->item->object.flags & SHOWN) &&
72                     !(parent->item->object.flags & UNINTERESTING))
73                         return 1;
74         return 0;
75 }
76
77 /* Since intptr_t is C99, we do not use it here */
78 static inline uint32_t *mark_to_ptr(uint32_t mark)
79 {
80         return ((uint32_t *)NULL) + mark;
81 }
82
83 static inline uint32_t ptr_to_mark(void * mark)
84 {
85         return (uint32_t *)mark - (uint32_t *)NULL;
86 }
87
88 static inline void mark_object(struct object *object, uint32_t mark)
89 {
90         add_decoration(&idnums, object, mark_to_ptr(mark));
91 }
92
93 static inline void mark_next_object(struct object *object)
94 {
95         mark_object(object, ++last_idnum);
96 }
97
98 static int get_object_mark(struct object *object)
99 {
100         void *decoration = lookup_decoration(&idnums, object);
101         if (!decoration)
102                 return 0;
103         return ptr_to_mark(decoration);
104 }
105
106 static void show_progress(void)
107 {
108         static int counter = 0;
109         if (!progress)
110                 return;
111         if ((++counter % progress) == 0)
112                 printf("progress %d objects\n", counter);
113 }
114
115 static void handle_object(const unsigned char *sha1)
116 {
117         unsigned long size;
118         enum object_type type;
119         char *buf;
120         struct object *object;
121
122         if (no_data)
123                 return;
124
125         if (is_null_sha1(sha1))
126                 return;
127
128         object = parse_object(sha1);
129         if (!object)
130                 die ("Could not read blob %s", sha1_to_hex(sha1));
131
132         if (object->flags & SHOWN)
133                 return;
134
135         buf = read_sha1_file(sha1, &type, &size);
136         if (!buf)
137                 die ("Could not read blob %s", sha1_to_hex(sha1));
138
139         mark_next_object(object);
140
141         printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
142         if (size && fwrite(buf, size, 1, stdout) != 1)
143                 die_errno ("Could not write blob '%s'", sha1_to_hex(sha1));
144         printf("\n");
145
146         show_progress();
147
148         object->flags |= SHOWN;
149         free(buf);
150 }
151
152 static int depth_first(const void *a_, const void *b_)
153 {
154         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
155         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
156         const char *name_a, *name_b;
157         int len_a, len_b, len;
158         int cmp;
159
160         name_a = a->one ? a->one->path : a->two->path;
161         name_b = b->one ? b->one->path : b->two->path;
162
163         len_a = strlen(name_a);
164         len_b = strlen(name_b);
165         len = (len_a < len_b) ? len_a : len_b;
166
167         /* strcmp will sort 'd' before 'd/e', we want 'd/e' before 'd' */
168         cmp = memcmp(name_a, name_b, len);
169         if (cmp)
170                 return cmp;
171         cmp = len_b - len_a;
172         if (cmp)
173                 return cmp;
174         /*
175          * Move 'R'ename entries last so that all references of the file
176          * appear in the output before it is renamed (e.g., when a file
177          * was copied and renamed in the same commit).
178          */
179         return (a->status == 'R') - (b->status == 'R');
180 }
181
182 static void print_path(const char *path)
183 {
184         int need_quote = quote_c_style(path, NULL, NULL, 0);
185         if (need_quote)
186                 quote_c_style(path, NULL, stdout, 0);
187         else
188                 printf("%s", path);
189 }
190
191 static void show_filemodify(struct diff_queue_struct *q,
192                             struct diff_options *options, void *data)
193 {
194         int i;
195
196         /*
197          * Handle files below a directory first, in case they are all deleted
198          * and the directory changes to a file or symlink.
199          */
200         qsort(q->queue, q->nr, sizeof(q->queue[0]), depth_first);
201
202         for (i = 0; i < q->nr; i++) {
203                 struct diff_filespec *ospec = q->queue[i]->one;
204                 struct diff_filespec *spec = q->queue[i]->two;
205
206                 switch (q->queue[i]->status) {
207                 case DIFF_STATUS_DELETED:
208                         printf("D ");
209                         print_path(spec->path);
210                         putchar('\n');
211                         break;
212
213                 case DIFF_STATUS_COPIED:
214                 case DIFF_STATUS_RENAMED:
215                         printf("%c ", q->queue[i]->status);
216                         print_path(ospec->path);
217                         putchar(' ');
218                         print_path(spec->path);
219                         putchar('\n');
220
221                         if (!hashcmp(ospec->sha1, spec->sha1) &&
222                             ospec->mode == spec->mode)
223                                 break;
224                         /* fallthrough */
225
226                 case DIFF_STATUS_TYPE_CHANGED:
227                 case DIFF_STATUS_MODIFIED:
228                 case DIFF_STATUS_ADDED:
229                         /*
230                          * Links refer to objects in another repositories;
231                          * output the SHA-1 verbatim.
232                          */
233                         if (no_data || S_ISGITLINK(spec->mode))
234                                 printf("M %06o %s ", spec->mode,
235                                        sha1_to_hex(spec->sha1));
236                         else {
237                                 struct object *object = lookup_object(spec->sha1);
238                                 printf("M %06o :%d ", spec->mode,
239                                        get_object_mark(object));
240                         }
241                         print_path(spec->path);
242                         putchar('\n');
243                         break;
244
245                 default:
246                         die("Unexpected comparison status '%c' for %s, %s",
247                                 q->queue[i]->status,
248                                 ospec->path ? ospec->path : "none",
249                                 spec->path ? spec->path : "none");
250                 }
251         }
252 }
253
254 static const char *find_encoding(const char *begin, const char *end)
255 {
256         const char *needle = "\nencoding ";
257         char *bol, *eol;
258
259         bol = memmem(begin, end ? end - begin : strlen(begin),
260                      needle, strlen(needle));
261         if (!bol)
262                 return git_commit_encoding;
263         bol += strlen(needle);
264         eol = strchrnul(bol, '\n');
265         *eol = '\0';
266         return bol;
267 }
268
269 static void handle_commit(struct commit *commit, struct rev_info *rev)
270 {
271         int saved_output_format = rev->diffopt.output_format;
272         const char *author, *author_end, *committer, *committer_end;
273         const char *encoding, *message;
274         char *reencoded = NULL;
275         struct commit_list *p;
276         int i;
277
278         rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
279
280         parse_commit(commit);
281         author = strstr(commit->buffer, "\nauthor ");
282         if (!author)
283                 die ("Could not find author in commit %s",
284                      sha1_to_hex(commit->object.sha1));
285         author++;
286         author_end = strchrnul(author, '\n');
287         committer = strstr(author_end, "\ncommitter ");
288         if (!committer)
289                 die ("Could not find committer in commit %s",
290                      sha1_to_hex(commit->object.sha1));
291         committer++;
292         committer_end = strchrnul(committer, '\n');
293         message = strstr(committer_end, "\n\n");
294         encoding = find_encoding(committer_end, message);
295         if (message)
296                 message += 2;
297
298         if (commit->parents &&
299             get_object_mark(&commit->parents->item->object) != 0 &&
300             !full_tree) {
301                 parse_commit(commit->parents->item);
302                 diff_tree_sha1(commit->parents->item->tree->object.sha1,
303                                commit->tree->object.sha1, "", &rev->diffopt);
304         }
305         else
306                 diff_root_tree_sha1(commit->tree->object.sha1,
307                                     "", &rev->diffopt);
308
309         /* Export the referenced blobs, and remember the marks. */
310         for (i = 0; i < diff_queued_diff.nr; i++)
311                 if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
312                         handle_object(diff_queued_diff.queue[i]->two->sha1);
313
314         mark_next_object(&commit->object);
315         if (!is_encoding_utf8(encoding))
316                 reencoded = reencode_string(message, "UTF-8", encoding);
317         if (!commit->parents)
318                 printf("reset %s\n", (const char*)commit->util);
319         printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
320                (const char *)commit->util, last_idnum,
321                (int)(author_end - author), author,
322                (int)(committer_end - committer), committer,
323                (unsigned)(reencoded
324                           ? strlen(reencoded) : message
325                           ? strlen(message) : 0),
326                reencoded ? reencoded : message ? message : "");
327         free(reencoded);
328
329         for (i = 0, p = commit->parents; p; p = p->next) {
330                 int mark = get_object_mark(&p->item->object);
331                 if (!mark)
332                         continue;
333                 if (i == 0)
334                         printf("from :%d\n", mark);
335                 else
336                         printf("merge :%d\n", mark);
337                 i++;
338         }
339
340         if (full_tree)
341                 printf("deleteall\n");
342         log_tree_diff_flush(rev);
343         rev->diffopt.output_format = saved_output_format;
344
345         printf("\n");
346
347         show_progress();
348 }
349
350 static void handle_tail(struct object_array *commits, struct rev_info *revs)
351 {
352         struct commit *commit;
353         while (commits->nr) {
354                 commit = (struct commit *)commits->objects[commits->nr - 1].item;
355                 if (has_unshown_parent(commit))
356                         return;
357                 handle_commit(commit, revs);
358                 commits->nr--;
359         }
360 }
361
362 static void handle_tag(const char *name, struct tag *tag)
363 {
364         unsigned long size;
365         enum object_type type;
366         char *buf;
367         const char *tagger, *tagger_end, *message;
368         size_t message_size = 0;
369         struct object *tagged;
370         int tagged_mark;
371         struct commit *p;
372
373         /* Trees have no identifer in fast-export output, thus we have no way
374          * to output tags of trees, tags of tags of trees, etc.  Simply omit
375          * such tags.
376          */
377         tagged = tag->tagged;
378         while (tagged->type == OBJ_TAG) {
379                 tagged = ((struct tag *)tagged)->tagged;
380         }
381         if (tagged->type == OBJ_TREE) {
382                 warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
383                         sha1_to_hex(tag->object.sha1));
384                 return;
385         }
386
387         buf = read_sha1_file(tag->object.sha1, &type, &size);
388         if (!buf)
389                 die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
390         message = memmem(buf, size, "\n\n", 2);
391         if (message) {
392                 message += 2;
393                 message_size = strlen(message);
394         }
395         tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
396         if (!tagger) {
397                 if (fake_missing_tagger)
398                         tagger = "tagger Unspecified Tagger "
399                                 "<unspecified-tagger> 0 +0000";
400                 else
401                         tagger = "";
402                 tagger_end = tagger + strlen(tagger);
403         } else {
404                 tagger++;
405                 tagger_end = strchrnul(tagger, '\n');
406         }
407
408         /* handle signed tags */
409         if (message) {
410                 const char *signature = strstr(message,
411                                                "\n-----BEGIN PGP SIGNATURE-----\n");
412                 if (signature)
413                         switch(signed_tag_mode) {
414                         case ABORT:
415                                 die ("Encountered signed tag %s; use "
416                                      "--signed-tag=<mode> to handle it.",
417                                      sha1_to_hex(tag->object.sha1));
418                         case WARN:
419                                 warning ("Exporting signed tag %s",
420                                          sha1_to_hex(tag->object.sha1));
421                                 /* fallthru */
422                         case VERBATIM:
423                                 break;
424                         case STRIP:
425                                 message_size = signature + 1 - message;
426                                 break;
427                         }
428         }
429
430         /* handle tag->tagged having been filtered out due to paths specified */
431         tagged = tag->tagged;
432         tagged_mark = get_object_mark(tagged);
433         if (!tagged_mark) {
434                 switch(tag_of_filtered_mode) {
435                 case ABORT:
436                         die ("Tag %s tags unexported object; use "
437                              "--tag-of-filtered-object=<mode> to handle it.",
438                              sha1_to_hex(tag->object.sha1));
439                 case DROP:
440                         /* Ignore this tag altogether */
441                         return;
442                 case REWRITE:
443                         if (tagged->type != OBJ_COMMIT) {
444                                 die ("Tag %s tags unexported %s!",
445                                      sha1_to_hex(tag->object.sha1),
446                                      typename(tagged->type));
447                         }
448                         p = (struct commit *)tagged;
449                         for (;;) {
450                                 if (p->parents && p->parents->next)
451                                         break;
452                                 if (p->object.flags & UNINTERESTING)
453                                         break;
454                                 if (!(p->object.flags & TREESAME))
455                                         break;
456                                 if (!p->parents)
457                                         die ("Can't find replacement commit for tag %s\n",
458                                              sha1_to_hex(tag->object.sha1));
459                                 p = p->parents->item;
460                         }
461                         tagged_mark = get_object_mark(&p->object);
462                 }
463         }
464
465         if (!prefixcmp(name, "refs/tags/"))
466                 name += 10;
467         printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
468                name, tagged_mark,
469                (int)(tagger_end - tagger), tagger,
470                tagger == tagger_end ? "" : "\n",
471                (int)message_size, (int)message_size, message ? message : "");
472 }
473
474 static void get_tags_and_duplicates(struct object_array *pending,
475                                     struct string_list *extra_refs)
476 {
477         struct tag *tag;
478         int i;
479
480         for (i = 0; i < pending->nr; i++) {
481                 struct object_array_entry *e = pending->objects + i;
482                 unsigned char sha1[20];
483                 struct commit *commit = commit;
484                 char *full_name;
485
486                 if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
487                         continue;
488
489                 switch (e->item->type) {
490                 case OBJ_COMMIT:
491                         commit = (struct commit *)e->item;
492                         break;
493                 case OBJ_TAG:
494                         tag = (struct tag *)e->item;
495
496                         /* handle nested tags */
497                         while (tag && tag->object.type == OBJ_TAG) {
498                                 parse_object(tag->object.sha1);
499                                 string_list_append(extra_refs, full_name)->util = tag;
500                                 tag = (struct tag *)tag->tagged;
501                         }
502                         if (!tag)
503                                 die ("Tag %s points nowhere?", e->name);
504                         switch(tag->object.type) {
505                         case OBJ_COMMIT:
506                                 commit = (struct commit *)tag;
507                                 break;
508                         case OBJ_BLOB:
509                                 handle_object(tag->object.sha1);
510                                 continue;
511                         default: /* OBJ_TAG (nested tags) is already handled */
512                                 warning("Tag points to object of unexpected type %s, skipping.",
513                                         typename(tag->object.type));
514                                 continue;
515                         }
516                         break;
517                 default:
518                         warning("%s: Unexpected object of type %s, skipping.",
519                                 e->name,
520                                 typename(e->item->type));
521                         continue;
522                 }
523                 if (commit->util)
524                         /* more than one name for the same object */
525                         string_list_append(extra_refs, full_name)->util = commit;
526                 else
527                         commit->util = full_name;
528         }
529 }
530
531 static void handle_tags_and_duplicates(struct string_list *extra_refs)
532 {
533         struct commit *commit;
534         int i;
535
536         for (i = extra_refs->nr - 1; i >= 0; i--) {
537                 const char *name = extra_refs->items[i].string;
538                 struct object *object = extra_refs->items[i].util;
539                 switch (object->type) {
540                 case OBJ_TAG:
541                         handle_tag(name, (struct tag *)object);
542                         break;
543                 case OBJ_COMMIT:
544                         /* create refs pointing to already seen commits */
545                         commit = (struct commit *)object;
546                         printf("reset %s\nfrom :%d\n\n", name,
547                                get_object_mark(&commit->object));
548                         show_progress();
549                         break;
550                 }
551         }
552 }
553
554 static void export_marks(char *file)
555 {
556         unsigned int i;
557         uint32_t mark;
558         struct object_decoration *deco = idnums.hash;
559         FILE *f;
560         int e = 0;
561
562         f = fopen(file, "w");
563         if (!f)
564                 die_errno("Unable to open marks file %s for writing.", file);
565
566         for (i = 0; i < idnums.size; i++) {
567                 if (deco->base && deco->base->type == 1) {
568                         mark = ptr_to_mark(deco->decoration);
569                         if (fprintf(f, ":%"PRIu32" %s\n", mark,
570                                 sha1_to_hex(deco->base->sha1)) < 0) {
571                             e = 1;
572                             break;
573                         }
574                 }
575                 deco++;
576         }
577
578         e |= ferror(f);
579         e |= fclose(f);
580         if (e)
581                 error("Unable to write marks file %s.", file);
582 }
583
584 static void import_marks(char *input_file)
585 {
586         char line[512];
587         FILE *f = fopen(input_file, "r");
588         if (!f)
589                 die_errno("cannot read '%s'", input_file);
590
591         while (fgets(line, sizeof(line), f)) {
592                 uint32_t mark;
593                 char *line_end, *mark_end;
594                 unsigned char sha1[20];
595                 struct object *object;
596
597                 line_end = strchr(line, '\n');
598                 if (line[0] != ':' || !line_end)
599                         die("corrupt mark line: %s", line);
600                 *line_end = '\0';
601
602                 mark = strtoumax(line + 1, &mark_end, 10);
603                 if (!mark || mark_end == line + 1
604                         || *mark_end != ' ' || get_sha1(mark_end + 1, sha1))
605                         die("corrupt mark line: %s", line);
606
607                 object = parse_object(sha1);
608                 if (!object)
609                         die ("Could not read blob %s", sha1_to_hex(sha1));
610
611                 if (object->flags & SHOWN)
612                         error("Object %s already has a mark", sha1);
613
614                 mark_object(object, mark);
615                 if (last_idnum < mark)
616                         last_idnum = mark;
617
618                 object->flags |= SHOWN;
619         }
620         fclose(f);
621 }
622
623 int cmd_fast_export(int argc, const char **argv, const char *prefix)
624 {
625         struct rev_info revs;
626         struct object_array commits = OBJECT_ARRAY_INIT;
627         struct string_list extra_refs = STRING_LIST_INIT_NODUP;
628         struct commit *commit;
629         char *export_filename = NULL, *import_filename = NULL;
630         struct option options[] = {
631                 OPT_INTEGER(0, "progress", &progress,
632                             "show progress after <n> objects"),
633                 OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, "mode",
634                              "select handling of signed tags",
635                              parse_opt_signed_tag_mode),
636                 OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, "mode",
637                              "select handling of tags that tag filtered objects",
638                              parse_opt_tag_of_filtered_mode),
639                 OPT_STRING(0, "export-marks", &export_filename, "file",
640                              "Dump marks to this file"),
641                 OPT_STRING(0, "import-marks", &import_filename, "file",
642                              "Import marks from this file"),
643                 OPT_BOOLEAN(0, "fake-missing-tagger", &fake_missing_tagger,
644                              "Fake a tagger when tags lack one"),
645                 OPT_BOOLEAN(0, "full-tree", &full_tree,
646                              "Output full tree for each commit"),
647                 { OPTION_NEGBIT, 0, "data", &no_data, NULL,
648                         "Skip output of blob data",
649                         PARSE_OPT_NOARG | PARSE_OPT_NEGHELP, NULL, 1 },
650                 OPT_END()
651         };
652
653         if (argc == 1)
654                 usage_with_options (fast_export_usage, options);
655
656         /* we handle encodings */
657         git_config(git_default_config, NULL);
658
659         init_revisions(&revs, prefix);
660         revs.topo_order = 1;
661         revs.show_source = 1;
662         revs.rewrite_parents = 1;
663         argc = setup_revisions(argc, argv, &revs, NULL);
664         argc = parse_options(argc, argv, prefix, options, fast_export_usage, 0);
665         if (argc > 1)
666                 usage_with_options (fast_export_usage, options);
667
668         if (import_filename)
669                 import_marks(import_filename);
670
671         if (import_filename && revs.prune_data.nr)
672                 full_tree = 1;
673
674         get_tags_and_duplicates(&revs.pending, &extra_refs);
675
676         if (prepare_revision_walk(&revs))
677                 die("revision walk setup failed");
678         revs.diffopt.format_callback = show_filemodify;
679         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
680         while ((commit = get_revision(&revs))) {
681                 if (has_unshown_parent(commit)) {
682                         add_object_array(&commit->object, NULL, &commits);
683                 }
684                 else {
685                         handle_commit(commit, &revs);
686                         handle_tail(&commits, &revs);
687                 }
688         }
689
690         handle_tags_and_duplicates(&extra_refs);
691
692         if (export_filename)
693                 export_marks(export_filename);
694
695         return 0;
696 }