51f4c546ee97847022d11997c07f5e150481e707
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
14struct batch_options {
15 int enabled;
16 int follow_symlinks;
17 int print_contents;
18 int buffer_output;
19 int all_objects;
20 const char *format;
21};
22
23static const char *force_path;
24
25static int filter_object(const char *path, unsigned mode,
26 const unsigned char *sha1,
27 char **buf, unsigned long *size)
28{
29 enum object_type type;
30
31 *buf = read_sha1_file(sha1, &type, size);
32 if (!*buf)
33 return error(_("cannot read object %s '%s'"),
34 sha1_to_hex(sha1), path);
35 if ((type == OBJ_BLOB) && S_ISREG(mode)) {
36 struct strbuf strbuf = STRBUF_INIT;
37 if (convert_to_working_tree(path, *buf, *size, &strbuf)) {
38 free(*buf);
39 *size = strbuf.len;
40 *buf = strbuf_detach(&strbuf, NULL);
41 }
42 }
43
44 return 0;
45}
46
47static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
48 int unknown_type)
49{
50 unsigned char sha1[20];
51 enum object_type type;
52 char *buf;
53 unsigned long size;
54 struct object_context obj_context;
55 struct object_info oi = {NULL};
56 struct strbuf sb = STRBUF_INIT;
57 unsigned flags = LOOKUP_REPLACE_OBJECT;
58 const char *path = force_path;
59
60 if (unknown_type)
61 flags |= LOOKUP_UNKNOWN_OBJECT;
62
63 if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
64 die("Not a valid object name %s", obj_name);
65
66 if (!path)
67 path = obj_context.path;
68 if (obj_context.mode == S_IFINVALID)
69 obj_context.mode = 0100644;
70
71 buf = NULL;
72 switch (opt) {
73 case 't':
74 oi.typename = &sb;
75 if (sha1_object_info_extended(sha1, &oi, flags) < 0)
76 die("git cat-file: could not get object info");
77 if (sb.len) {
78 printf("%s\n", sb.buf);
79 strbuf_release(&sb);
80 return 0;
81 }
82 break;
83
84 case 's':
85 oi.sizep = &size;
86 if (sha1_object_info_extended(sha1, &oi, flags) < 0)
87 die("git cat-file: could not get object info");
88 printf("%lu\n", size);
89 return 0;
90
91 case 'e':
92 return !has_sha1_file(sha1);
93
94 case 'w':
95 if (!path[0])
96 die("git cat-file --filters %s: <object> must be "
97 "<sha1:path>", obj_name);
98
99 if (filter_object(path, obj_context.mode,
100 sha1, &buf, &size))
101 return -1;
102 break;
103
104 case 'c':
105 if (!path[0])
106 die("git cat-file --textconv %s: <object> must be <sha1:path>",
107 obj_name);
108
109 if (textconv_object(path, obj_context.mode,
110 sha1, 1, &buf, &size))
111 break;
112
113 case 'p':
114 type = sha1_object_info(sha1, 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, sha1, NULL, 0);
128 buf = read_sha1_file(sha1, &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 unsigned char blob_sha1[20];
138 if (sha1_object_info(sha1, NULL) == OBJ_TAG) {
139 char *buffer = read_sha1_file(sha1, &type, &size);
140 const char *target;
141 if (!skip_prefix(buffer, "object ", &target) ||
142 get_sha1_hex(target, blob_sha1))
143 die("%s not a valid tag", sha1_to_hex(sha1));
144 free(buffer);
145 } else
146 hashcpy(blob_sha1, sha1);
147
148 if (sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
149 return stream_blob_to_fd(1, blob_sha1, 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(sha1, 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
171struct expand_data {
172 unsigned char sha1[20];
173 enum object_type type;
174 unsigned long size;
175 off_t disk_size;
176 const char *rest;
177 unsigned char delta_base_sha1[20];
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
207static 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
213static 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, sha1_to_hex(data->sha1));
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_sha1;
244 else
245 strbuf_addstr(sb, sha1_to_hex(data->delta_base_sha1));
246 } else
247 die("unknown format element: %.*s", len, atom);
248}
249
250static size_t expand_format(struct strbuf *sb, const char *start, void *data)
251{
252 const char *end;
253
254 if (*start != '(')
255 return 0;
256 end = strchr(start + 1, ')');
257 if (!end)
258 die("format element '%s' does not end in ')'", start);
259
260 expand_atom(sb, start + 1, end - start - 1, data);
261
262 return end - start + 1;
263}
264
265static void batch_write(struct batch_options *opt, const void *data, int len)
266{
267 if (opt->buffer_output) {
268 if (fwrite(data, 1, len, stdout) != len)
269 die_errno("unable to write to stdout");
270 } else
271 write_or_die(1, data, len);
272}
273
274static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
275{
276 const unsigned char *sha1 = data->sha1;
277
278 assert(data->info.typep);
279
280 if (data->type == OBJ_BLOB) {
281 if (opt->buffer_output)
282 fflush(stdout);
283 if (stream_blob_to_fd(1, sha1, NULL, 0) < 0)
284 die("unable to stream %s to stdout", sha1_to_hex(sha1));
285 }
286 else {
287 enum object_type type;
288 unsigned long size;
289 void *contents;
290
291 contents = read_sha1_file(sha1, &type, &size);
292 if (!contents)
293 die("object %s disappeared", sha1_to_hex(sha1));
294 if (type != data->type)
295 die("object %s changed type!?", sha1_to_hex(sha1));
296 if (data->info.sizep && size != data->size)
297 die("object %s changed size!?", sha1_to_hex(sha1));
298
299 batch_write(opt, contents, size);
300 free(contents);
301 }
302}
303
304static void batch_object_write(const char *obj_name, struct batch_options *opt,
305 struct expand_data *data)
306{
307 struct strbuf buf = STRBUF_INIT;
308
309 if (!data->skip_object_info &&
310 sha1_object_info_extended(data->sha1, &data->info, LOOKUP_REPLACE_OBJECT) < 0) {
311 printf("%s missing\n", obj_name ? obj_name : sha1_to_hex(data->sha1));
312 fflush(stdout);
313 return;
314 }
315
316 strbuf_expand(&buf, opt->format, expand_format, data);
317 strbuf_addch(&buf, '\n');
318 batch_write(opt, buf.buf, buf.len);
319 strbuf_release(&buf);
320
321 if (opt->print_contents) {
322 print_object_or_die(opt, data);
323 batch_write(opt, "\n", 1);
324 }
325}
326
327static void batch_one_object(const char *obj_name, struct batch_options *opt,
328 struct expand_data *data)
329{
330 struct object_context ctx;
331 int flags = opt->follow_symlinks ? GET_SHA1_FOLLOW_SYMLINKS : 0;
332 enum follow_symlinks_result result;
333
334 result = get_sha1_with_context(obj_name, flags, data->sha1, &ctx);
335 if (result != FOUND) {
336 switch (result) {
337 case MISSING_OBJECT:
338 printf("%s missing\n", obj_name);
339 break;
340 case DANGLING_SYMLINK:
341 printf("dangling %"PRIuMAX"\n%s\n",
342 (uintmax_t)strlen(obj_name), obj_name);
343 break;
344 case SYMLINK_LOOP:
345 printf("loop %"PRIuMAX"\n%s\n",
346 (uintmax_t)strlen(obj_name), obj_name);
347 break;
348 case NOT_DIR:
349 printf("notdir %"PRIuMAX"\n%s\n",
350 (uintmax_t)strlen(obj_name), obj_name);
351 break;
352 default:
353 die("BUG: unknown get_sha1_with_context result %d\n",
354 result);
355 break;
356 }
357 fflush(stdout);
358 return;
359 }
360
361 if (ctx.mode == 0) {
362 printf("symlink %"PRIuMAX"\n%s\n",
363 (uintmax_t)ctx.symlink_path.len,
364 ctx.symlink_path.buf);
365 fflush(stdout);
366 return;
367 }
368
369 batch_object_write(obj_name, opt, data);
370}
371
372struct object_cb_data {
373 struct batch_options *opt;
374 struct expand_data *expand;
375};
376
377static void batch_object_cb(const unsigned char sha1[20], void *vdata)
378{
379 struct object_cb_data *data = vdata;
380 hashcpy(data->expand->sha1, sha1);
381 batch_object_write(NULL, data->opt, data->expand);
382}
383
384static int batch_loose_object(const unsigned char *sha1,
385 const char *path,
386 void *data)
387{
388 sha1_array_append(data, sha1);
389 return 0;
390}
391
392static int batch_packed_object(const unsigned char *sha1,
393 struct packed_git *pack,
394 uint32_t pos,
395 void *data)
396{
397 sha1_array_append(data, sha1);
398 return 0;
399}
400
401static int batch_objects(struct batch_options *opt)
402{
403 struct strbuf buf = STRBUF_INIT;
404 struct expand_data data;
405 int save_warning;
406 int retval = 0;
407
408 if (!opt->format)
409 opt->format = "%(objectname) %(objecttype) %(objectsize)";
410
411 /*
412 * Expand once with our special mark_query flag, which will prime the
413 * object_info to be handed to sha1_object_info_extended for each
414 * object.
415 */
416 memset(&data, 0, sizeof(data));
417 data.mark_query = 1;
418 strbuf_expand(&buf, opt->format, expand_format, &data);
419 data.mark_query = 0;
420
421 if (opt->all_objects) {
422 struct object_info empty;
423 memset(&empty, 0, sizeof(empty));
424 if (!memcmp(&data.info, &empty, sizeof(empty)))
425 data.skip_object_info = 1;
426 }
427
428 /*
429 * If we are printing out the object, then always fill in the type,
430 * since we will want to decide whether or not to stream.
431 */
432 if (opt->print_contents)
433 data.info.typep = &data.type;
434
435 if (opt->all_objects) {
436 struct sha1_array sa = SHA1_ARRAY_INIT;
437 struct object_cb_data cb;
438
439 for_each_loose_object(batch_loose_object, &sa, 0);
440 for_each_packed_object(batch_packed_object, &sa, 0);
441
442 cb.opt = opt;
443 cb.expand = &data;
444 sha1_array_for_each_unique(&sa, batch_object_cb, &cb);
445
446 sha1_array_clear(&sa);
447 return 0;
448 }
449
450 /*
451 * We are going to call get_sha1 on a potentially very large number of
452 * objects. In most large cases, these will be actual object sha1s. The
453 * cost to double-check that each one is not also a ref (just so we can
454 * warn) ends up dwarfing the actual cost of the object lookups
455 * themselves. We can work around it by just turning off the warning.
456 */
457 save_warning = warn_on_object_refname_ambiguity;
458 warn_on_object_refname_ambiguity = 0;
459
460 while (strbuf_getline(&buf, stdin) != EOF) {
461 if (data.split_on_whitespace) {
462 /*
463 * Split at first whitespace, tying off the beginning
464 * of the string and saving the remainder (or NULL) in
465 * data.rest.
466 */
467 char *p = strpbrk(buf.buf, " \t");
468 if (p) {
469 while (*p && strchr(" \t", *p))
470 *p++ = '\0';
471 }
472 data.rest = p;
473 }
474
475 batch_one_object(buf.buf, opt, &data);
476 }
477
478 strbuf_release(&buf);
479 warn_on_object_refname_ambiguity = save_warning;
480 return retval;
481}
482
483static const char * const cat_file_usage[] = {
484 N_("git cat-file (-t [--allow-unknown-type]|-s [--allow-unknown-type]|-e|-p|<type>|--textconv|--filters) [--path=<path>] <object>"),
485 N_("git cat-file (--batch | --batch-check) [--follow-symlinks]"),
486 NULL
487};
488
489static int git_cat_file_config(const char *var, const char *value, void *cb)
490{
491 if (userdiff_config(var, value) < 0)
492 return -1;
493
494 return git_default_config(var, value, cb);
495}
496
497static int batch_option_callback(const struct option *opt,
498 const char *arg,
499 int unset)
500{
501 struct batch_options *bo = opt->value;
502
503 if (bo->enabled) {
504 return 1;
505 }
506
507 bo->enabled = 1;
508 bo->print_contents = !strcmp(opt->long_name, "batch");
509 bo->format = arg;
510
511 return 0;
512}
513
514int cmd_cat_file(int argc, const char **argv, const char *prefix)
515{
516 int opt = 0;
517 const char *exp_type = NULL, *obj_name = NULL;
518 struct batch_options batch = {0};
519 int unknown_type = 0;
520
521 const struct option options[] = {
522 OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
523 OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
524 OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
525 OPT_CMDMODE('e', NULL, &opt,
526 N_("exit with zero when there's no error"), 'e'),
527 OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
528 OPT_CMDMODE(0, "textconv", &opt,
529 N_("for blob objects, run textconv on object's content"), 'c'),
530 OPT_CMDMODE(0, "filters", &opt,
531 N_("for blob objects, run filters on object's content"), 'w'),
532 OPT_STRING(0, "path", &force_path, N_("blob"),
533 N_("use a specific path for --textconv/--filters")),
534 OPT_BOOL(0, "allow-unknown-type", &unknown_type,
535 N_("allow -s and -t to work with broken/corrupt objects")),
536 OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
537 { OPTION_CALLBACK, 0, "batch", &batch, "format",
538 N_("show info and content of objects fed from the standard input"),
539 PARSE_OPT_OPTARG, batch_option_callback },
540 { OPTION_CALLBACK, 0, "batch-check", &batch, "format",
541 N_("show info about objects fed from the standard input"),
542 PARSE_OPT_OPTARG, batch_option_callback },
543 OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
544 N_("follow in-tree symlinks (used with --batch or --batch-check)")),
545 OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
546 N_("show all objects with --batch or --batch-check")),
547 OPT_END()
548 };
549
550 git_config(git_cat_file_config, NULL);
551
552 batch.buffer_output = -1;
553 argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
554
555 if (opt) {
556 if (argc == 1)
557 obj_name = argv[0];
558 else
559 usage_with_options(cat_file_usage, options);
560 }
561 if (!opt && !batch.enabled) {
562 if (argc == 2) {
563 exp_type = argv[0];
564 obj_name = argv[1];
565 } else
566 usage_with_options(cat_file_usage, options);
567 }
568 if (batch.enabled && (opt || argc)) {
569 usage_with_options(cat_file_usage, options);
570 }
571
572 if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
573 usage_with_options(cat_file_usage, options);
574 }
575
576 if (force_path && opt != 'c' && opt != 'w') {
577 error("--path=<path> needs --textconv or --filters");
578 usage_with_options(cat_file_usage, options);
579 }
580
581 if (batch.buffer_output < 0)
582 batch.buffer_output = batch.all_objects;
583
584 if (batch.enabled)
585 return batch_objects(&batch);
586
587 if (unknown_type && opt != 't' && opt != 's')
588 die("git cat-file --allow-unknown-type: use with -s or -t");
589 return cat_one_file(opt, exp_type, obj_name, unknown_type);
590}