Teach "diff --check" about new blank lines at end
[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 :%d\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                         struct object *object = lookup_object(spec->sha1);
140                         printf("M %06o :%d %s\n", spec->mode,
141                                get_object_mark(object), spec->path);
142                 }
143         }
144 }
145
146 static const char *find_encoding(const char *begin, const char *end)
147 {
148         const char *needle = "\nencoding ";
149         char *bol, *eol;
150
151         bol = memmem(begin, end ? end - begin : strlen(begin),
152                      needle, strlen(needle));
153         if (!bol)
154                 return git_commit_encoding;
155         bol += strlen(needle);
156         eol = strchrnul(bol, '\n');
157         *eol = '\0';
158         return bol;
159 }
160
161 static void handle_commit(struct commit *commit, struct rev_info *rev)
162 {
163         int saved_output_format = rev->diffopt.output_format;
164         const char *author, *author_end, *committer, *committer_end;
165         const char *encoding, *message;
166         char *reencoded = NULL;
167         struct commit_list *p;
168         int i;
169
170         rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
171
172         parse_commit(commit);
173         author = strstr(commit->buffer, "\nauthor ");
174         if (!author)
175                 die ("Could not find author in commit %s",
176                      sha1_to_hex(commit->object.sha1));
177         author++;
178         author_end = strchrnul(author, '\n');
179         committer = strstr(author_end, "\ncommitter ");
180         if (!committer)
181                 die ("Could not find committer in commit %s",
182                      sha1_to_hex(commit->object.sha1));
183         committer++;
184         committer_end = strchrnul(committer, '\n');
185         message = strstr(committer_end, "\n\n");
186         encoding = find_encoding(committer_end, message);
187         if (message)
188                 message += 2;
189
190         if (commit->parents) {
191                 parse_commit(commit->parents->item);
192                 diff_tree_sha1(commit->parents->item->tree->object.sha1,
193                                commit->tree->object.sha1, "", &rev->diffopt);
194         }
195         else
196                 diff_root_tree_sha1(commit->tree->object.sha1,
197                                     "", &rev->diffopt);
198
199         for (i = 0; i < diff_queued_diff.nr; i++)
200                 handle_object(diff_queued_diff.queue[i]->two->sha1);
201
202         mark_next_object(&commit->object);
203         if (!is_encoding_utf8(encoding))
204                 reencoded = reencode_string(message, "UTF-8", encoding);
205         if (!commit->parents)
206                 printf("reset %s\n", (const char*)commit->util);
207         printf("commit %s\nmark :%d\n%.*s\n%.*s\ndata %u\n%s",
208                (const char *)commit->util, last_idnum,
209                (int)(author_end - author), author,
210                (int)(committer_end - committer), committer,
211                (unsigned)(reencoded
212                           ? strlen(reencoded) : message
213                           ? strlen(message) : 0),
214                reencoded ? reencoded : message ? message : "");
215         free(reencoded);
216
217         for (i = 0, p = commit->parents; p; p = p->next) {
218                 int mark = get_object_mark(&p->item->object);
219                 if (!mark)
220                         continue;
221                 if (i == 0)
222                         printf("from :%d\n", mark);
223                 else
224                         printf("merge :%d\n", mark);
225                 i++;
226         }
227
228         log_tree_diff_flush(rev);
229         rev->diffopt.output_format = saved_output_format;
230
231         printf("\n");
232
233         show_progress();
234 }
235
236 static void handle_tail(struct object_array *commits, struct rev_info *revs)
237 {
238         struct commit *commit;
239         while (commits->nr) {
240                 commit = (struct commit *)commits->objects[commits->nr - 1].item;
241                 if (has_unshown_parent(commit))
242                         return;
243                 handle_commit(commit, revs);
244                 commits->nr--;
245         }
246 }
247
248 static void handle_tag(const char *name, struct tag *tag)
249 {
250         unsigned long size;
251         enum object_type type;
252         char *buf;
253         const char *tagger, *tagger_end, *message;
254         size_t message_size = 0;
255
256         buf = read_sha1_file(tag->object.sha1, &type, &size);
257         if (!buf)
258                 die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
259         message = memmem(buf, size, "\n\n", 2);
260         if (message) {
261                 message += 2;
262                 message_size = strlen(message);
263         }
264         tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
265         if (!tagger)
266                 die ("No tagger for tag %s", sha1_to_hex(tag->object.sha1));
267         tagger++;
268         tagger_end = strchrnul(tagger, '\n');
269
270         /* handle signed tags */
271         if (message) {
272                 const char *signature = strstr(message,
273                                                "\n-----BEGIN PGP SIGNATURE-----\n");
274                 if (signature)
275                         switch(signed_tag_mode) {
276                         case ABORT:
277                                 die ("Encountered signed tag %s; use "
278                                      "--signed-tag=<mode> to handle it.",
279                                      sha1_to_hex(tag->object.sha1));
280                         case WARN:
281                                 warning ("Exporting signed tag %s",
282                                          sha1_to_hex(tag->object.sha1));
283                                 /* fallthru */
284                         case VERBATIM:
285                                 break;
286                         case STRIP:
287                                 message_size = signature + 1 - message;
288                                 break;
289                         }
290         }
291
292         if (!prefixcmp(name, "refs/tags/"))
293                 name += 10;
294         printf("tag %s\nfrom :%d\n%.*s\ndata %d\n%.*s\n",
295                name, get_object_mark(tag->tagged),
296                (int)(tagger_end - tagger), tagger,
297                (int)message_size, (int)message_size, message ? message : "");
298 }
299
300 static void get_tags_and_duplicates(struct object_array *pending,
301                                     struct path_list *extra_refs)
302 {
303         struct tag *tag;
304         int i;
305
306         for (i = 0; i < pending->nr; i++) {
307                 struct object_array_entry *e = pending->objects + i;
308                 unsigned char sha1[20];
309                 struct commit *commit = commit;
310                 char *full_name;
311
312                 if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
313                         continue;
314
315                 switch (e->item->type) {
316                 case OBJ_COMMIT:
317                         commit = (struct commit *)e->item;
318                         break;
319                 case OBJ_TAG:
320                         tag = (struct tag *)e->item;
321                         while (tag && tag->object.type == OBJ_TAG) {
322                                 path_list_insert(full_name, extra_refs)->util = tag;
323                                 tag = (struct tag *)tag->tagged;
324                         }
325                         if (!tag)
326                                 die ("Tag %s points nowhere?", e->name);
327                         switch(tag->object.type) {
328                         case OBJ_COMMIT:
329                                 commit = (struct commit *)tag;
330                                 break;
331                         case OBJ_BLOB:
332                                 handle_object(tag->object.sha1);
333                                 continue;
334                         }
335                         break;
336                 default:
337                         die ("Unexpected object of type %s",
338                              typename(e->item->type));
339                 }
340                 if (commit->util)
341                         /* more than one name for the same object */
342                         path_list_insert(full_name, extra_refs)->util = commit;
343                 else
344                         commit->util = full_name;
345         }
346 }
347
348 static void handle_tags_and_duplicates(struct path_list *extra_refs)
349 {
350         struct commit *commit;
351         int i;
352
353         for (i = extra_refs->nr - 1; i >= 0; i--) {
354                 const char *name = extra_refs->items[i].path;
355                 struct object *object = extra_refs->items[i].util;
356                 switch (object->type) {
357                 case OBJ_TAG:
358                         handle_tag(name, (struct tag *)object);
359                         break;
360                 case OBJ_COMMIT:
361                         /* create refs pointing to already seen commits */
362                         commit = (struct commit *)object;
363                         printf("reset %s\nfrom :%d\n\n", name,
364                                get_object_mark(&commit->object));
365                         show_progress();
366                         break;
367                 }
368         }
369 }
370
371 static void export_marks(char *file)
372 {
373         unsigned int i;
374         uint32_t mark;
375         struct object_decoration *deco = idnums.hash;
376         FILE *f;
377
378         f = fopen(file, "w");
379         if (!f)
380                 error("Unable to open marks file %s for writing", file);
381
382         for (i = 0; i < idnums.size; ++i) {
383                 deco++;
384                 if (deco && deco->base && deco->base->type == 1) {
385                         mark = ptr_to_mark(deco->decoration);
386                         fprintf(f, ":%u %s\n", mark, sha1_to_hex(deco->base->sha1));
387                 }
388         }
389
390         if (ferror(f) || fclose(f))
391                 error("Unable to write marks file %s.", file);
392 }
393
394 static void import_marks(char * input_file)
395 {
396         char line[512];
397         FILE *f = fopen(input_file, "r");
398         if (!f)
399                 die("cannot read %s: %s", input_file, strerror(errno));
400
401         while (fgets(line, sizeof(line), f)) {
402                 uint32_t mark;
403                 char *line_end, *mark_end;
404                 unsigned char sha1[20];
405                 struct object *object;
406
407                 line_end = strchr(line, '\n');
408                 if (line[0] != ':' || !line_end)
409                         die("corrupt mark line: %s", line);
410                 *line_end = 0;
411
412                 mark = strtoumax(line + 1, &mark_end, 10);
413                 if (!mark || mark_end == line + 1
414                         || *mark_end != ' ' || get_sha1(mark_end + 1, sha1))
415                         die("corrupt mark line: %s", line);
416
417                 object = parse_object(sha1);
418                 if (!object)
419                         die ("Could not read blob %s", sha1_to_hex(sha1));
420
421                 if (object->flags & SHOWN)
422                         error("Object %s already has a mark", sha1);
423
424                 mark_object(object, mark);
425                 if (last_idnum < mark)
426                         last_idnum = mark;
427
428                 object->flags |= SHOWN;
429         }
430         fclose(f);
431 }
432
433 int cmd_fast_export(int argc, const char **argv, const char *prefix)
434 {
435         struct rev_info revs;
436         struct object_array commits = { 0, 0, NULL };
437         struct path_list extra_refs = { NULL, 0, 0, 0 };
438         struct commit *commit;
439         char *export_filename = NULL, *import_filename = NULL;
440         struct option options[] = {
441                 OPT_INTEGER(0, "progress", &progress,
442                             "show progress after <n> objects"),
443                 OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, "mode",
444                              "select handling of signed tags",
445                              parse_opt_signed_tag_mode),
446                 OPT_STRING(0, "export-marks", &export_filename, "FILE",
447                              "Dump marks to this file"),
448                 OPT_STRING(0, "import-marks", &import_filename, "FILE",
449                              "Import marks from this file"),
450                 OPT_END()
451         };
452
453         /* we handle encodings */
454         git_config(git_default_config, NULL);
455
456         init_revisions(&revs, prefix);
457         argc = setup_revisions(argc, argv, &revs, NULL);
458         argc = parse_options(argc, argv, options, fast_export_usage, 0);
459         if (argc > 1)
460                 usage_with_options (fast_export_usage, options);
461
462         if (import_filename)
463                 import_marks(import_filename);
464
465         get_tags_and_duplicates(&revs.pending, &extra_refs);
466
467         if (prepare_revision_walk(&revs))
468                 die("revision walk setup failed");
469         revs.diffopt.format_callback = show_filemodify;
470         DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
471         while ((commit = get_revision(&revs))) {
472                 if (has_unshown_parent(commit)) {
473                         struct commit_list *parent = commit->parents;
474                         add_object_array(&commit->object, NULL, &commits);
475                         for (; parent; parent = parent->next)
476                                 if (!parent->item->util)
477                                         parent->item->util = commit->util;
478                 }
479                 else {
480                         handle_commit(commit, &revs);
481                         handle_tail(&commits, &revs);
482                 }
483         }
484
485         handle_tags_and_duplicates(&extra_refs);
486
487         if (export_filename)
488                 export_marks(export_filename);
489
490         return 0;
491 }