Merge branch 'js/mingw-isatty'
[git/git.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 "builtin.h"
8 #include "parse-options.h"
9 #include "userdiff.h"
10 #include "streaming.h"
11 #include "tree-walk.h"
12 #include "sha1-array.h"
13
14 struct batch_options {
15 int enabled;
16 int follow_symlinks;
17 int print_contents;
18 int buffer_output;
19 int all_objects;
20 int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
21 const char *format;
22 };
23
24 static const char *force_path;
25
26 static int filter_object(const char *path, unsigned mode,
27 const struct object_id *oid,
28 char **buf, unsigned long *size)
29 {
30 enum object_type type;
31
32 *buf = read_sha1_file(oid->hash, &type, size);
33 if (!*buf)
34 return error(_("cannot read object %s '%s'"),
35 oid_to_hex(oid), path);
36 if ((type == OBJ_BLOB) && S_ISREG(mode)) {
37 struct strbuf strbuf = STRBUF_INIT;
38 if (convert_to_working_tree(path, *buf, *size, &strbuf)) {
39 free(*buf);
40 *size = strbuf.len;
41 *buf = strbuf_detach(&strbuf, NULL);
42 }
43 }
44
45 return 0;
46 }
47
48 static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
49 int unknown_type)
50 {
51 struct object_id oid;
52 enum object_type type;
53 char *buf;
54 unsigned long size;
55 struct object_context obj_context;
56 struct object_info oi = OBJECT_INFO_INIT;
57 struct strbuf sb = STRBUF_INIT;
58 unsigned flags = LOOKUP_REPLACE_OBJECT;
59 const char *path = force_path;
60
61 if (unknown_type)
62 flags |= LOOKUP_UNKNOWN_OBJECT;
63
64 if (get_sha1_with_context(obj_name, 0, oid.hash, &obj_context))
65 die("Not a valid object name %s", obj_name);
66
67 if (!path)
68 path = obj_context.path;
69 if (obj_context.mode == S_IFINVALID)
70 obj_context.mode = 0100644;
71
72 buf = NULL;
73 switch (opt) {
74 case 't':
75 oi.typename = &sb;
76 if (sha1_object_info_extended(oid.hash, &oi, flags) < 0)
77 die("git cat-file: could not get object info");
78 if (sb.len) {
79 printf("%s\n", sb.buf);
80 strbuf_release(&sb);
81 return 0;
82 }
83 break;
84
85 case 's':
86 oi.sizep = &size;
87 if (sha1_object_info_extended(oid.hash, &oi, flags) < 0)
88 die("git cat-file: could not get object info");
89 printf("%lu\n", size);
90 return 0;
91
92 case 'e':
93 return !has_object_file(&oid);
94
95 case 'w':
96 if (!path[0])
97 die("git cat-file --filters %s: <object> must be "
98 "<sha1:path>", obj_name);
99
100 if (filter_object(path, obj_context.mode,
101 &oid, &buf, &size))
102 return -1;
103 break;
104
105 case 'c':
106 if (!path[0])
107 die("git cat-file --textconv %s: <object> must be <sha1:path>",
108 obj_name);
109
110 if (textconv_object(path, obj_context.mode, &oid, 1, &buf, &size))
111 break;
112
113 case 'p':
114 type = sha1_object_info(oid.hash, NULL);
115 if (type < 0)
116 die("Not a valid object name %s", obj_name);
117
118 /* custom pretty-print here */
119 if (type == OBJ_TREE) {
120 const char *ls_args[3] = { NULL };
121 ls_args[0] = "ls-tree";
122 ls_args[1] = obj_name;
123 return cmd_ls_tree(2, ls_args, NULL);
124 }
125
126 if (type == OBJ_BLOB)
127 return stream_blob_to_fd(1, &oid, NULL, 0);
128 buf = read_sha1_file(oid.hash, &type, &size);
129 if (!buf)
130 die("Cannot read object %s", obj_name);
131
132 /* otherwise just spit out the data */
133 break;
134
135 case 0:
136 if (type_from_string(exp_type) == OBJ_BLOB) {
137 struct object_id blob_oid;
138 if (sha1_object_info(oid.hash, NULL) == OBJ_TAG) {
139 char *buffer = read_sha1_file(oid.hash, &type, &size);
140 const char *target;
141 if (!skip_prefix(buffer, "object ", &target) ||
142 get_oid_hex(target, &blob_oid))
143 die("%s not a valid tag", oid_to_hex(&oid));
144 free(buffer);
145 } else
146 oidcpy(&blob_oid, &oid);
147
148 if (sha1_object_info(blob_oid.hash, NULL) == OBJ_BLOB)
149 return stream_blob_to_fd(1, &blob_oid, NULL, 0);
150 /*
151 * we attempted to dereference a tag to a blob
152 * and failed; there may be new dereference
153 * mechanisms this code is not aware of.
154 * fall-back to the usual case.
155 */
156 }
157 buf = read_object_with_reference(oid.hash, exp_type, &size, NULL);
158 break;
159
160 default:
161 die("git cat-file: unknown option: %s", exp_type);
162 }
163
164 if (!buf)
165 die("git cat-file %s: bad file", obj_name);
166
167 write_or_die(1, buf, size);
168 return 0;
169 }
170
171 struct expand_data {
172 struct object_id oid;
173 enum object_type type;
174 unsigned long size;
175 off_t disk_size;
176 const char *rest;
177 struct object_id delta_base_oid;
178
179 /*
180 * If mark_query is true, we do not expand anything, but rather
181 * just mark the object_info with items we wish to query.
182 */
183 int mark_query;
184
185 /*
186 * Whether to split the input on whitespace before feeding it to
187 * get_sha1; this is decided during the mark_query phase based on
188 * whether we have a %(rest) token in our format.
189 */
190 int split_on_whitespace;
191
192 /*
193 * After a mark_query run, this object_info is set up to be
194 * passed to sha1_object_info_extended. It will point to the data
195 * elements above, so you can retrieve the response from there.
196 */
197 struct object_info info;
198
199 /*
200 * This flag will be true if the requested batch format and options
201 * don't require us to call sha1_object_info, which can then be
202 * optimized out.
203 */
204 unsigned skip_object_info : 1;
205 };
206
207 static int is_atom(const char *atom, const char *s, int slen)
208 {
209 int alen = strlen(atom);
210 return alen == slen && !memcmp(atom, s, alen);
211 }
212
213 static void expand_atom(struct strbuf *sb, const char *atom, int len,
214 void *vdata)
215 {
216 struct expand_data *data = vdata;
217
218 if (is_atom("objectname", atom, len)) {
219 if (!data->mark_query)
220 strbuf_addstr(sb, oid_to_hex(&data->oid));
221 } else if (is_atom("objecttype", atom, len)) {
222 if (data->mark_query)
223 data->info.typep = &data->type;
224 else
225 strbuf_addstr(sb, typename(data->type));
226 } else if (is_atom("objectsize", atom, len)) {
227 if (data->mark_query)
228 data->info.sizep = &data->size;
229 else
230 strbuf_addf(sb, "%lu", data->size);
231 } else if (is_atom("objectsize:disk", atom, len)) {
232 if (data->mark_query)
233 data->info.disk_sizep = &data->disk_size;
234 else
235 strbuf_addf(sb, "%"PRIuMAX, (uintmax_t)data->disk_size);
236 } else if (is_atom("rest", atom, len)) {
237 if (data->mark_query)
238 data->split_on_whitespace = 1;
239 else if (data->rest)
240 strbuf_addstr(sb, data->rest);
241 } else if (is_atom("deltabase", atom, len)) {
242 if (data->mark_query)
243 data->info.delta_base_sha1 = data->delta_base_oid.hash;
244 else
245 strbuf_addstr(sb,
246 oid_to_hex(&data->delta_base_oid));
247 } else
248 die("unknown format element: %.*s", len, atom);
249 }
250
251 static size_t expand_format(struct strbuf *sb, const char *start, void *data)
252 {
253 const char *end;
254
255 if (*start != '(')
256 return 0;
257 end = strchr(start + 1, ')');
258 if (!end)
259 die("format element '%s' does not end in ')'", start);
260
261 expand_atom(sb, start + 1, end - start - 1, data);
262
263 return end - start + 1;
264 }
265
266 static void batch_write(struct batch_options *opt, const void *data, int len)
267 {
268 if (opt->buffer_output) {
269 if (fwrite(data, 1, len, stdout) != len)
270 die_errno("unable to write to stdout");
271 } else
272 write_or_die(1, data, len);
273 }
274
275 static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
276 {
277 const struct object_id *oid = &data->oid;
278
279 assert(data->info.typep);
280
281 if (data->type == OBJ_BLOB) {
282 if (opt->buffer_output)
283 fflush(stdout);
284 if (opt->cmdmode) {
285 char *contents;
286 unsigned long size;
287
288 if (!data->rest)
289 die("missing path for '%s'", oid_to_hex(oid));
290
291 if (opt->cmdmode == 'w') {
292 if (filter_object(data->rest, 0100644, oid,
293 &contents, &size))
294 die("could not convert '%s' %s",
295 oid_to_hex(oid), data->rest);
296 } else if (opt->cmdmode == 'c') {
297 enum object_type type;
298 if (!textconv_object(data->rest, 0100644, oid,
299 1, &contents, &size))
300 contents = read_sha1_file(oid->hash, &type,
301 &size);
302 if (!contents)
303 die("could not convert '%s' %s",
304 oid_to_hex(oid), data->rest);
305 } else
306 die("BUG: invalid cmdmode: %c", opt->cmdmode);
307 batch_write(opt, contents, size);
308 free(contents);
309 } else if (stream_blob_to_fd(1, oid, NULL, 0) < 0)
310 die("unable to stream %s to stdout", oid_to_hex(oid));
311 }
312 else {
313 enum object_type type;
314 unsigned long size;
315 void *contents;
316
317 contents = read_sha1_file(oid->hash, &type, &size);
318 if (!contents)
319 die("object %s disappeared", oid_to_hex(oid));
320 if (type != data->type)
321 die("object %s changed type!?", oid_to_hex(oid));
322 if (data->info.sizep && size != data->size)
323 die("object %s changed size!?", oid_to_hex(oid));
324
325 batch_write(opt, contents, size);
326 free(contents);
327 }
328 }
329
330 static void batch_object_write(const char *obj_name, struct batch_options *opt,
331 struct expand_data *data)
332 {
333 struct strbuf buf = STRBUF_INIT;
334
335 if (!data->skip_object_info &&
336 sha1_object_info_extended(data->oid.hash, &data->info, LOOKUP_REPLACE_OBJECT) < 0) {
337 printf("%s missing\n",
338 obj_name ? obj_name : oid_to_hex(&data->oid));
339 fflush(stdout);
340 return;
341 }
342
343 strbuf_expand(&buf, opt->format, expand_format, data);
344 strbuf_addch(&buf, '\n');
345 batch_write(opt, buf.buf, buf.len);
346 strbuf_release(&buf);
347
348 if (opt->print_contents) {
349 print_object_or_die(opt, data);
350 batch_write(opt, "\n", 1);
351 }
352 }
353
354 static void batch_one_object(const char *obj_name, struct batch_options *opt,
355 struct expand_data *data)
356 {
357 struct object_context ctx;
358 int flags = opt->follow_symlinks ? GET_SHA1_FOLLOW_SYMLINKS : 0;
359 enum follow_symlinks_result result;
360
361 result = get_sha1_with_context(obj_name, flags, data->oid.hash, &ctx);
362 if (result != FOUND) {
363 switch (result) {
364 case MISSING_OBJECT:
365 printf("%s missing\n", obj_name);
366 break;
367 case DANGLING_SYMLINK:
368 printf("dangling %"PRIuMAX"\n%s\n",
369 (uintmax_t)strlen(obj_name), obj_name);
370 break;
371 case SYMLINK_LOOP:
372 printf("loop %"PRIuMAX"\n%s\n",
373 (uintmax_t)strlen(obj_name), obj_name);
374 break;
375 case NOT_DIR:
376 printf("notdir %"PRIuMAX"\n%s\n",
377 (uintmax_t)strlen(obj_name), obj_name);
378 break;
379 default:
380 die("BUG: unknown get_sha1_with_context result %d\n",
381 result);
382 break;
383 }
384 fflush(stdout);
385 return;
386 }
387
388 if (ctx.mode == 0) {
389 printf("symlink %"PRIuMAX"\n%s\n",
390 (uintmax_t)ctx.symlink_path.len,
391 ctx.symlink_path.buf);
392 fflush(stdout);
393 return;
394 }
395
396 batch_object_write(obj_name, opt, data);
397 }
398
399 struct object_cb_data {
400 struct batch_options *opt;
401 struct expand_data *expand;
402 };
403
404 static int batch_object_cb(const unsigned char sha1[20], void *vdata)
405 {
406 struct object_cb_data *data = vdata;
407 hashcpy(data->expand->oid.hash, sha1);
408 batch_object_write(NULL, data->opt, data->expand);
409 return 0;
410 }
411
412 static int batch_loose_object(const unsigned char *sha1,
413 const char *path,
414 void *data)
415 {
416 sha1_array_append(data, sha1);
417 return 0;
418 }
419
420 static int batch_packed_object(const unsigned char *sha1,
421 struct packed_git *pack,
422 uint32_t pos,
423 void *data)
424 {
425 sha1_array_append(data, sha1);
426 return 0;
427 }
428
429 static int batch_objects(struct batch_options *opt)
430 {
431 struct strbuf buf = STRBUF_INIT;
432 struct expand_data data;
433 int save_warning;
434 int retval = 0;
435
436 if (!opt->format)
437 opt->format = "%(objectname) %(objecttype) %(objectsize)";
438
439 /*
440 * Expand once with our special mark_query flag, which will prime the
441 * object_info to be handed to sha1_object_info_extended for each
442 * object.
443 */
444 memset(&data, 0, sizeof(data));
445 data.mark_query = 1;
446 strbuf_expand(&buf, opt->format, expand_format, &data);
447 data.mark_query = 0;
448 if (opt->cmdmode)
449 data.split_on_whitespace = 1;
450
451 if (opt->all_objects) {
452 struct object_info empty = OBJECT_INFO_INIT;
453 if (!memcmp(&data.info, &empty, sizeof(empty)))
454 data.skip_object_info = 1;
455 }
456
457 /*
458 * If we are printing out the object, then always fill in the type,
459 * since we will want to decide whether or not to stream.
460 */
461 if (opt->print_contents)
462 data.info.typep = &data.type;
463
464 if (opt->all_objects) {
465 struct sha1_array sa = SHA1_ARRAY_INIT;
466 struct object_cb_data cb;
467
468 for_each_loose_object(batch_loose_object, &sa, 0);
469 for_each_packed_object(batch_packed_object, &sa, 0);
470
471 cb.opt = opt;
472 cb.expand = &data;
473 sha1_array_for_each_unique(&sa, batch_object_cb, &cb);
474
475 sha1_array_clear(&sa);
476 return 0;
477 }
478
479 /*
480 * We are going to call get_sha1 on a potentially very large number of
481 * objects. In most large cases, these will be actual object sha1s. The
482 * cost to double-check that each one is not also a ref (just so we can
483 * warn) ends up dwarfing the actual cost of the object lookups
484 * themselves. We can work around it by just turning off the warning.
485 */
486 save_warning = warn_on_object_refname_ambiguity;
487 warn_on_object_refname_ambiguity = 0;
488
489 while (strbuf_getline(&buf, stdin) != EOF) {
490 if (data.split_on_whitespace) {
491 /*
492 * Split at first whitespace, tying off the beginning
493 * of the string and saving the remainder (or NULL) in
494 * data.rest.
495 */
496 char *p = strpbrk(buf.buf, " \t");
497 if (p) {
498 while (*p && strchr(" \t", *p))
499 *p++ = '\0';
500 }
501 data.rest = p;
502 }
503
504 batch_one_object(buf.buf, opt, &data);
505 }
506
507 strbuf_release(&buf);
508 warn_on_object_refname_ambiguity = save_warning;
509 return retval;
510 }
511
512 static const char * const cat_file_usage[] = {
513 N_("git cat-file (-t [--allow-unknown-type] | -s [--allow-unknown-type] | -e | -p | <type> | --textconv | --filters) [--path=<path>] <object>"),
514 N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv | --filters]"),
515 NULL
516 };
517
518 static int git_cat_file_config(const char *var, const char *value, void *cb)
519 {
520 if (userdiff_config(var, value) < 0)
521 return -1;
522
523 return git_default_config(var, value, cb);
524 }
525
526 static int batch_option_callback(const struct option *opt,
527 const char *arg,
528 int unset)
529 {
530 struct batch_options *bo = opt->value;
531
532 if (bo->enabled) {
533 return 1;
534 }
535
536 bo->enabled = 1;
537 bo->print_contents = !strcmp(opt->long_name, "batch");
538 bo->format = arg;
539
540 return 0;
541 }
542
543 int cmd_cat_file(int argc, const char **argv, const char *prefix)
544 {
545 int opt = 0;
546 const char *exp_type = NULL, *obj_name = NULL;
547 struct batch_options batch = {0};
548 int unknown_type = 0;
549
550 const struct option options[] = {
551 OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
552 OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
553 OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
554 OPT_CMDMODE('e', NULL, &opt,
555 N_("exit with zero when there's no error"), 'e'),
556 OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
557 OPT_CMDMODE(0, "textconv", &opt,
558 N_("for blob objects, run textconv on object's content"), 'c'),
559 OPT_CMDMODE(0, "filters", &opt,
560 N_("for blob objects, run filters on object's content"), 'w'),
561 OPT_STRING(0, "path", &force_path, N_("blob"),
562 N_("use a specific path for --textconv/--filters")),
563 OPT_BOOL(0, "allow-unknown-type", &unknown_type,
564 N_("allow -s and -t to work with broken/corrupt objects")),
565 OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
566 { OPTION_CALLBACK, 0, "batch", &batch, "format",
567 N_("show info and content of objects fed from the standard input"),
568 PARSE_OPT_OPTARG, batch_option_callback },
569 { OPTION_CALLBACK, 0, "batch-check", &batch, "format",
570 N_("show info about objects fed from the standard input"),
571 PARSE_OPT_OPTARG, batch_option_callback },
572 OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
573 N_("follow in-tree symlinks (used with --batch or --batch-check)")),
574 OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
575 N_("show all objects with --batch or --batch-check")),
576 OPT_END()
577 };
578
579 git_config(git_cat_file_config, NULL);
580
581 batch.buffer_output = -1;
582 argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
583
584 if (opt) {
585 if (batch.enabled && (opt == 'c' || opt == 'w'))
586 batch.cmdmode = opt;
587 else if (argc == 1)
588 obj_name = argv[0];
589 else
590 usage_with_options(cat_file_usage, options);
591 }
592 if (!opt && !batch.enabled) {
593 if (argc == 2) {
594 exp_type = argv[0];
595 obj_name = argv[1];
596 } else
597 usage_with_options(cat_file_usage, options);
598 }
599 if (batch.enabled) {
600 if (batch.cmdmode != opt || argc)
601 usage_with_options(cat_file_usage, options);
602 if (batch.cmdmode && batch.all_objects)
603 die("--batch-all-objects cannot be combined with "
604 "--textconv nor with --filters");
605 }
606
607 if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
608 usage_with_options(cat_file_usage, options);
609 }
610
611 if (force_path && opt != 'c' && opt != 'w') {
612 error("--path=<path> needs --textconv or --filters");
613 usage_with_options(cat_file_usage, options);
614 }
615
616 if (force_path && batch.enabled) {
617 error("--path=<path> incompatible with --batch");
618 usage_with_options(cat_file_usage, options);
619 }
620
621 if (batch.buffer_output < 0)
622 batch.buffer_output = batch.all_objects;
623
624 if (batch.enabled)
625 return batch_objects(&batch);
626
627 if (unknown_type && opt != 't' && opt != 's')
628 die("git cat-file --allow-unknown-type: use with -s or -t");
629 return cat_one_file(opt, exp_type, obj_name, unknown_type);
630 }