Merge branch 'tq/refs-internal-comment-fix'
[git] / builtin / cat-file.c
1 /*
2  * GIT - The information manager from hell
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "config.h"
8 #include "builtin.h"
9 #include "diff.h"
10 #include "parse-options.h"
11 #include "userdiff.h"
12 #include "streaming.h"
13 #include "tree-walk.h"
14 #include "sha1-array.h"
15 #include "packfile.h"
16 #include "object-store.h"
17
18 struct batch_options {
19         int enabled;
20         int follow_symlinks;
21         int print_contents;
22         int buffer_output;
23         int all_objects;
24         int unordered;
25         int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
26         const char *format;
27 };
28
29 static const char *force_path;
30
31 static int filter_object(const char *path, unsigned mode,
32                          const struct object_id *oid,
33                          char **buf, unsigned long *size)
34 {
35         enum object_type type;
36
37         *buf = read_object_file(oid, &type, size);
38         if (!*buf)
39                 return error(_("cannot read object %s '%s'"),
40                              oid_to_hex(oid), path);
41         if ((type == OBJ_BLOB) && S_ISREG(mode)) {
42                 struct strbuf strbuf = STRBUF_INIT;
43                 if (convert_to_working_tree(&the_index, path, *buf, *size, &strbuf)) {
44                         free(*buf);
45                         *size = strbuf.len;
46                         *buf = strbuf_detach(&strbuf, NULL);
47                 }
48         }
49
50         return 0;
51 }
52
53 static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
54                         int unknown_type)
55 {
56         struct object_id oid;
57         enum object_type type;
58         char *buf;
59         unsigned long size;
60         struct object_context obj_context;
61         struct object_info oi = OBJECT_INFO_INIT;
62         struct strbuf sb = STRBUF_INIT;
63         unsigned flags = OBJECT_INFO_LOOKUP_REPLACE;
64         const char *path = force_path;
65
66         if (unknown_type)
67                 flags |= OBJECT_INFO_ALLOW_UNKNOWN_TYPE;
68
69         if (get_oid_with_context(obj_name, GET_OID_RECORD_PATH,
70                                  &oid, &obj_context))
71                 die("Not a valid object name %s", obj_name);
72
73         if (!path)
74                 path = obj_context.path;
75         if (obj_context.mode == S_IFINVALID)
76                 obj_context.mode = 0100644;
77
78         buf = NULL;
79         switch (opt) {
80         case 't':
81                 oi.type_name = &sb;
82                 if (oid_object_info_extended(the_repository, &oid, &oi, flags) < 0)
83                         die("git cat-file: could not get object info");
84                 if (sb.len) {
85                         printf("%s\n", sb.buf);
86                         strbuf_release(&sb);
87                         return 0;
88                 }
89                 break;
90
91         case 's':
92                 oi.sizep = &size;
93                 if (oid_object_info_extended(the_repository, &oid, &oi, flags) < 0)
94                         die("git cat-file: could not get object info");
95                 printf("%lu\n", size);
96                 return 0;
97
98         case 'e':
99                 return !has_object_file(&oid);
100
101         case 'w':
102                 if (!path)
103                         die("git cat-file --filters %s: <object> must be "
104                             "<sha1:path>", obj_name);
105
106                 if (filter_object(path, obj_context.mode,
107                                   &oid, &buf, &size))
108                         return -1;
109                 break;
110
111         case 'c':
112                 if (!path)
113                         die("git cat-file --textconv %s: <object> must be <sha1:path>",
114                             obj_name);
115
116                 if (textconv_object(path, obj_context.mode, &oid, 1, &buf, &size))
117                         break;
118                 /* else fallthrough */
119
120         case 'p':
121                 type = oid_object_info(the_repository, &oid, NULL);
122                 if (type < 0)
123                         die("Not a valid object name %s", obj_name);
124
125                 /* custom pretty-print here */
126                 if (type == OBJ_TREE) {
127                         const char *ls_args[3] = { NULL };
128                         ls_args[0] =  "ls-tree";
129                         ls_args[1] =  obj_name;
130                         return cmd_ls_tree(2, ls_args, NULL);
131                 }
132
133                 if (type == OBJ_BLOB)
134                         return stream_blob_to_fd(1, &oid, NULL, 0);
135                 buf = read_object_file(&oid, &type, &size);
136                 if (!buf)
137                         die("Cannot read object %s", obj_name);
138
139                 /* otherwise just spit out the data */
140                 break;
141
142         case 0:
143                 if (type_from_string(exp_type) == OBJ_BLOB) {
144                         struct object_id blob_oid;
145                         if (oid_object_info(the_repository, &oid, NULL) == OBJ_TAG) {
146                                 char *buffer = read_object_file(&oid, &type,
147                                                                 &size);
148                                 const char *target;
149                                 if (!skip_prefix(buffer, "object ", &target) ||
150                                     get_oid_hex(target, &blob_oid))
151                                         die("%s not a valid tag", oid_to_hex(&oid));
152                                 free(buffer);
153                         } else
154                                 oidcpy(&blob_oid, &oid);
155
156                         if (oid_object_info(the_repository, &blob_oid, NULL) == OBJ_BLOB)
157                                 return stream_blob_to_fd(1, &blob_oid, NULL, 0);
158                         /*
159                          * we attempted to dereference a tag to a blob
160                          * and failed; there may be new dereference
161                          * mechanisms this code is not aware of.
162                          * fall-back to the usual case.
163                          */
164                 }
165                 buf = read_object_with_reference(&oid, exp_type, &size, NULL);
166                 break;
167
168         default:
169                 die("git cat-file: unknown option: %s", exp_type);
170         }
171
172         if (!buf)
173                 die("git cat-file %s: bad file", obj_name);
174
175         write_or_die(1, buf, size);
176         free(buf);
177         free(obj_context.path);
178         return 0;
179 }
180
181 struct expand_data {
182         struct object_id oid;
183         enum object_type type;
184         unsigned long size;
185         off_t disk_size;
186         const char *rest;
187         struct object_id delta_base_oid;
188
189         /*
190          * If mark_query is true, we do not expand anything, but rather
191          * just mark the object_info with items we wish to query.
192          */
193         int mark_query;
194
195         /*
196          * Whether to split the input on whitespace before feeding it to
197          * get_sha1; this is decided during the mark_query phase based on
198          * whether we have a %(rest) token in our format.
199          */
200         int split_on_whitespace;
201
202         /*
203          * After a mark_query run, this object_info is set up to be
204          * passed to sha1_object_info_extended. It will point to the data
205          * elements above, so you can retrieve the response from there.
206          */
207         struct object_info info;
208
209         /*
210          * This flag will be true if the requested batch format and options
211          * don't require us to call sha1_object_info, which can then be
212          * optimized out.
213          */
214         unsigned skip_object_info : 1;
215 };
216
217 static int is_atom(const char *atom, const char *s, int slen)
218 {
219         int alen = strlen(atom);
220         return alen == slen && !memcmp(atom, s, alen);
221 }
222
223 static void expand_atom(struct strbuf *sb, const char *atom, int len,
224                         void *vdata)
225 {
226         struct expand_data *data = vdata;
227
228         if (is_atom("objectname", atom, len)) {
229                 if (!data->mark_query)
230                         strbuf_addstr(sb, oid_to_hex(&data->oid));
231         } else if (is_atom("objecttype", atom, len)) {
232                 if (data->mark_query)
233                         data->info.typep = &data->type;
234                 else
235                         strbuf_addstr(sb, type_name(data->type));
236         } else if (is_atom("objectsize", atom, len)) {
237                 if (data->mark_query)
238                         data->info.sizep = &data->size;
239                 else
240                         strbuf_addf(sb, "%lu", data->size);
241         } else if (is_atom("objectsize:disk", atom, len)) {
242                 if (data->mark_query)
243                         data->info.disk_sizep = &data->disk_size;
244                 else
245                         strbuf_addf(sb, "%"PRIuMAX, (uintmax_t)data->disk_size);
246         } else if (is_atom("rest", atom, len)) {
247                 if (data->mark_query)
248                         data->split_on_whitespace = 1;
249                 else if (data->rest)
250                         strbuf_addstr(sb, data->rest);
251         } else if (is_atom("deltabase", atom, len)) {
252                 if (data->mark_query)
253                         data->info.delta_base_sha1 = data->delta_base_oid.hash;
254                 else
255                         strbuf_addstr(sb,
256                                       oid_to_hex(&data->delta_base_oid));
257         } else
258                 die("unknown format element: %.*s", len, atom);
259 }
260
261 static size_t expand_format(struct strbuf *sb, const char *start, void *data)
262 {
263         const char *end;
264
265         if (*start != '(')
266                 return 0;
267         end = strchr(start + 1, ')');
268         if (!end)
269                 die("format element '%s' does not end in ')'", start);
270
271         expand_atom(sb, start + 1, end - start - 1, data);
272
273         return end - start + 1;
274 }
275
276 static void batch_write(struct batch_options *opt, const void *data, int len)
277 {
278         if (opt->buffer_output) {
279                 if (fwrite(data, 1, len, stdout) != len)
280                         die_errno("unable to write to stdout");
281         } else
282                 write_or_die(1, data, len);
283 }
284
285 static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
286 {
287         const struct object_id *oid = &data->oid;
288
289         assert(data->info.typep);
290
291         if (data->type == OBJ_BLOB) {
292                 if (opt->buffer_output)
293                         fflush(stdout);
294                 if (opt->cmdmode) {
295                         char *contents;
296                         unsigned long size;
297
298                         if (!data->rest)
299                                 die("missing path for '%s'", oid_to_hex(oid));
300
301                         if (opt->cmdmode == 'w') {
302                                 if (filter_object(data->rest, 0100644, oid,
303                                                   &contents, &size))
304                                         die("could not convert '%s' %s",
305                                             oid_to_hex(oid), data->rest);
306                         } else if (opt->cmdmode == 'c') {
307                                 enum object_type type;
308                                 if (!textconv_object(data->rest, 0100644, oid,
309                                                      1, &contents, &size))
310                                         contents = read_object_file(oid,
311                                                                     &type,
312                                                                     &size);
313                                 if (!contents)
314                                         die("could not convert '%s' %s",
315                                             oid_to_hex(oid), data->rest);
316                         } else
317                                 BUG("invalid cmdmode: %c", opt->cmdmode);
318                         batch_write(opt, contents, size);
319                         free(contents);
320                 } else if (stream_blob_to_fd(1, oid, NULL, 0) < 0)
321                         die("unable to stream %s to stdout", oid_to_hex(oid));
322         }
323         else {
324                 enum object_type type;
325                 unsigned long size;
326                 void *contents;
327
328                 contents = read_object_file(oid, &type, &size);
329                 if (!contents)
330                         die("object %s disappeared", oid_to_hex(oid));
331                 if (type != data->type)
332                         die("object %s changed type!?", oid_to_hex(oid));
333                 if (data->info.sizep && size != data->size)
334                         die("object %s changed size!?", oid_to_hex(oid));
335
336                 batch_write(opt, contents, size);
337                 free(contents);
338         }
339 }
340
341 static void batch_object_write(const char *obj_name,
342                                struct strbuf *scratch,
343                                struct batch_options *opt,
344                                struct expand_data *data)
345 {
346         if (!data->skip_object_info &&
347             oid_object_info_extended(the_repository, &data->oid, &data->info,
348                                      OBJECT_INFO_LOOKUP_REPLACE) < 0) {
349                 printf("%s missing\n",
350                        obj_name ? obj_name : oid_to_hex(&data->oid));
351                 fflush(stdout);
352                 return;
353         }
354
355         strbuf_reset(scratch);
356         strbuf_expand(scratch, opt->format, expand_format, data);
357         strbuf_addch(scratch, '\n');
358         batch_write(opt, scratch->buf, scratch->len);
359
360         if (opt->print_contents) {
361                 print_object_or_die(opt, data);
362                 batch_write(opt, "\n", 1);
363         }
364 }
365
366 static void batch_one_object(const char *obj_name,
367                              struct strbuf *scratch,
368                              struct batch_options *opt,
369                              struct expand_data *data)
370 {
371         struct object_context ctx;
372         int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
373         enum follow_symlinks_result result;
374
375         result = get_oid_with_context(obj_name, flags, &data->oid, &ctx);
376         if (result != FOUND) {
377                 switch (result) {
378                 case MISSING_OBJECT:
379                         printf("%s missing\n", obj_name);
380                         break;
381                 case DANGLING_SYMLINK:
382                         printf("dangling %"PRIuMAX"\n%s\n",
383                                (uintmax_t)strlen(obj_name), obj_name);
384                         break;
385                 case SYMLINK_LOOP:
386                         printf("loop %"PRIuMAX"\n%s\n",
387                                (uintmax_t)strlen(obj_name), obj_name);
388                         break;
389                 case NOT_DIR:
390                         printf("notdir %"PRIuMAX"\n%s\n",
391                                (uintmax_t)strlen(obj_name), obj_name);
392                         break;
393                 default:
394                         BUG("unknown get_sha1_with_context result %d\n",
395                                result);
396                         break;
397                 }
398                 fflush(stdout);
399                 return;
400         }
401
402         if (ctx.mode == 0) {
403                 printf("symlink %"PRIuMAX"\n%s\n",
404                        (uintmax_t)ctx.symlink_path.len,
405                        ctx.symlink_path.buf);
406                 fflush(stdout);
407                 return;
408         }
409
410         batch_object_write(obj_name, scratch, opt, data);
411 }
412
413 struct object_cb_data {
414         struct batch_options *opt;
415         struct expand_data *expand;
416         struct oidset *seen;
417         struct strbuf *scratch;
418 };
419
420 static int batch_object_cb(const struct object_id *oid, void *vdata)
421 {
422         struct object_cb_data *data = vdata;
423         oidcpy(&data->expand->oid, oid);
424         batch_object_write(NULL, data->scratch, data->opt, data->expand);
425         return 0;
426 }
427
428 static int collect_loose_object(const struct object_id *oid,
429                                 const char *path,
430                                 void *data)
431 {
432         oid_array_append(data, oid);
433         return 0;
434 }
435
436 static int collect_packed_object(const struct object_id *oid,
437                                  struct packed_git *pack,
438                                  uint32_t pos,
439                                  void *data)
440 {
441         oid_array_append(data, oid);
442         return 0;
443 }
444
445 static int batch_unordered_object(const struct object_id *oid, void *vdata)
446 {
447         struct object_cb_data *data = vdata;
448
449         if (oidset_insert(data->seen, oid))
450                 return 0;
451
452         return batch_object_cb(oid, data);
453 }
454
455 static int batch_unordered_loose(const struct object_id *oid,
456                                  const char *path,
457                                  void *data)
458 {
459         return batch_unordered_object(oid, data);
460 }
461
462 static int batch_unordered_packed(const struct object_id *oid,
463                                   struct packed_git *pack,
464                                   uint32_t pos,
465                                   void *data)
466 {
467         return batch_unordered_object(oid, data);
468 }
469
470 static int batch_objects(struct batch_options *opt)
471 {
472         struct strbuf input = STRBUF_INIT;
473         struct strbuf output = STRBUF_INIT;
474         struct expand_data data;
475         int save_warning;
476         int retval = 0;
477
478         if (!opt->format)
479                 opt->format = "%(objectname) %(objecttype) %(objectsize)";
480
481         /*
482          * Expand once with our special mark_query flag, which will prime the
483          * object_info to be handed to sha1_object_info_extended for each
484          * object.
485          */
486         memset(&data, 0, sizeof(data));
487         data.mark_query = 1;
488         strbuf_expand(&output, opt->format, expand_format, &data);
489         data.mark_query = 0;
490         strbuf_release(&output);
491         if (opt->cmdmode)
492                 data.split_on_whitespace = 1;
493
494         if (opt->all_objects) {
495                 struct object_info empty = OBJECT_INFO_INIT;
496                 if (!memcmp(&data.info, &empty, sizeof(empty)))
497                         data.skip_object_info = 1;
498         }
499
500         /*
501          * If we are printing out the object, then always fill in the type,
502          * since we will want to decide whether or not to stream.
503          */
504         if (opt->print_contents)
505                 data.info.typep = &data.type;
506
507         if (opt->all_objects) {
508                 struct object_cb_data cb;
509
510                 if (repository_format_partial_clone)
511                         warning("This repository has extensions.partialClone set. Some objects may not be loaded.");
512
513                 cb.opt = opt;
514                 cb.expand = &data;
515                 cb.scratch = &output;
516
517                 if (opt->unordered) {
518                         struct oidset seen = OIDSET_INIT;
519
520                         cb.seen = &seen;
521
522                         for_each_loose_object(batch_unordered_loose, &cb, 0);
523                         for_each_packed_object(batch_unordered_packed, &cb,
524                                                FOR_EACH_OBJECT_PACK_ORDER);
525
526                         oidset_clear(&seen);
527                 } else {
528                         struct oid_array sa = OID_ARRAY_INIT;
529
530                         for_each_loose_object(collect_loose_object, &sa, 0);
531                         for_each_packed_object(collect_packed_object, &sa, 0);
532
533                         oid_array_for_each_unique(&sa, batch_object_cb, &cb);
534
535                         oid_array_clear(&sa);
536                 }
537
538                 strbuf_release(&output);
539                 return 0;
540         }
541
542         /*
543          * We are going to call get_sha1 on a potentially very large number of
544          * objects. In most large cases, these will be actual object sha1s. The
545          * cost to double-check that each one is not also a ref (just so we can
546          * warn) ends up dwarfing the actual cost of the object lookups
547          * themselves. We can work around it by just turning off the warning.
548          */
549         save_warning = warn_on_object_refname_ambiguity;
550         warn_on_object_refname_ambiguity = 0;
551
552         while (strbuf_getline(&input, stdin) != EOF) {
553                 if (data.split_on_whitespace) {
554                         /*
555                          * Split at first whitespace, tying off the beginning
556                          * of the string and saving the remainder (or NULL) in
557                          * data.rest.
558                          */
559                         char *p = strpbrk(input.buf, " \t");
560                         if (p) {
561                                 while (*p && strchr(" \t", *p))
562                                         *p++ = '\0';
563                         }
564                         data.rest = p;
565                 }
566
567                 batch_one_object(input.buf, &output, opt, &data);
568         }
569
570         strbuf_release(&input);
571         strbuf_release(&output);
572         warn_on_object_refname_ambiguity = save_warning;
573         return retval;
574 }
575
576 static const char * const cat_file_usage[] = {
577         N_("git cat-file (-t [--allow-unknown-type] | -s [--allow-unknown-type] | -e | -p | <type> | --textconv | --filters) [--path=<path>] <object>"),
578         N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv | --filters]"),
579         NULL
580 };
581
582 static int git_cat_file_config(const char *var, const char *value, void *cb)
583 {
584         if (userdiff_config(var, value) < 0)
585                 return -1;
586
587         return git_default_config(var, value, cb);
588 }
589
590 static int batch_option_callback(const struct option *opt,
591                                  const char *arg,
592                                  int unset)
593 {
594         struct batch_options *bo = opt->value;
595
596         if (bo->enabled) {
597                 return 1;
598         }
599
600         bo->enabled = 1;
601         bo->print_contents = !strcmp(opt->long_name, "batch");
602         bo->format = arg;
603
604         return 0;
605 }
606
607 int cmd_cat_file(int argc, const char **argv, const char *prefix)
608 {
609         int opt = 0;
610         const char *exp_type = NULL, *obj_name = NULL;
611         struct batch_options batch = {0};
612         int unknown_type = 0;
613
614         const struct option options[] = {
615                 OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
616                 OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
617                 OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
618                 OPT_CMDMODE('e', NULL, &opt,
619                             N_("exit with zero when there's no error"), 'e'),
620                 OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
621                 OPT_CMDMODE(0, "textconv", &opt,
622                             N_("for blob objects, run textconv on object's content"), 'c'),
623                 OPT_CMDMODE(0, "filters", &opt,
624                             N_("for blob objects, run filters on object's content"), 'w'),
625                 OPT_STRING(0, "path", &force_path, N_("blob"),
626                            N_("use a specific path for --textconv/--filters")),
627                 OPT_BOOL(0, "allow-unknown-type", &unknown_type,
628                           N_("allow -s and -t to work with broken/corrupt objects")),
629                 OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
630                 { OPTION_CALLBACK, 0, "batch", &batch, "format",
631                         N_("show info and content of objects fed from the standard input"),
632                         PARSE_OPT_OPTARG, batch_option_callback },
633                 { OPTION_CALLBACK, 0, "batch-check", &batch, "format",
634                         N_("show info about objects fed from the standard input"),
635                         PARSE_OPT_OPTARG, batch_option_callback },
636                 OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
637                          N_("follow in-tree symlinks (used with --batch or --batch-check)")),
638                 OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
639                          N_("show all objects with --batch or --batch-check")),
640                 OPT_BOOL(0, "unordered", &batch.unordered,
641                          N_("do not order --batch-all-objects output")),
642                 OPT_END()
643         };
644
645         git_config(git_cat_file_config, NULL);
646
647         batch.buffer_output = -1;
648         argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
649
650         if (opt) {
651                 if (batch.enabled && (opt == 'c' || opt == 'w'))
652                         batch.cmdmode = opt;
653                 else if (argc == 1)
654                         obj_name = argv[0];
655                 else
656                         usage_with_options(cat_file_usage, options);
657         }
658         if (!opt && !batch.enabled) {
659                 if (argc == 2) {
660                         exp_type = argv[0];
661                         obj_name = argv[1];
662                 } else
663                         usage_with_options(cat_file_usage, options);
664         }
665         if (batch.enabled) {
666                 if (batch.cmdmode != opt || argc)
667                         usage_with_options(cat_file_usage, options);
668                 if (batch.cmdmode && batch.all_objects)
669                         die("--batch-all-objects cannot be combined with "
670                             "--textconv nor with --filters");
671         }
672
673         if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
674                 usage_with_options(cat_file_usage, options);
675         }
676
677         if (force_path && opt != 'c' && opt != 'w') {
678                 error("--path=<path> needs --textconv or --filters");
679                 usage_with_options(cat_file_usage, options);
680         }
681
682         if (force_path && batch.enabled) {
683                 error("--path=<path> incompatible with --batch");
684                 usage_with_options(cat_file_usage, options);
685         }
686
687         if (batch.buffer_output < 0)
688                 batch.buffer_output = batch.all_objects;
689
690         if (batch.enabled)
691                 return batch_objects(&batch);
692
693         if (unknown_type && opt != 't' && opt != 's')
694                 die("git cat-file --allow-unknown-type: use with -s or -t");
695         return cat_one_file(opt, exp_type, obj_name, unknown_type);
696 }