bash completion: Add long options for 'git describe'
[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
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 string_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                                 string_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                         string_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 string_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].string;
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 string_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 }