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 "diff.h"
9#include "parse-options.h"
10#include "userdiff.h"
11#include "streaming.h"
12#include "tree-walk.h"
13#include "sha1-array.h"
14
15struct batch_options {
16 int enabled;
17 int follow_symlinks;
18 int print_contents;
19 int buffer_output;
20 int all_objects;
21 int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
22 const char *format;
23};
24
25static const char *force_path;
26
27static int filter_object(const char *path, unsigned mode,
28 const struct object_id *oid,
29 char **buf, unsigned long *size)
30{
31 enum object_type type;
32
33 *buf = read_sha1_file(oid->hash, &type, size);
34 if (!*buf)
35 return error(_("cannot read object %s '%s'"),
36 oid_to_hex(oid), path);
37 if ((type == OBJ_BLOB) && S_ISREG(mode)) {
38 struct strbuf strbuf = STRBUF_INIT;
39 if (convert_to_working_tree(path, *buf, *size, &strbuf)) {
40 free(*buf);
41 *size = strbuf.len;
42 *buf = strbuf_detach(&strbuf, NULL);
43 }
44 }
45
46 return 0;
47}
48
49static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
50 int unknown_type)
51{
52 struct object_id oid;
53 enum object_type type;
54 char *buf;
55 unsigned long size;
56 struct object_context obj_context;
57 struct object_info oi = OBJECT_INFO_INIT;
58 struct strbuf sb = STRBUF_INIT;
59 unsigned flags = OBJECT_INFO_LOOKUP_REPLACE;
60 const char *path = force_path;
61
62 if (unknown_type)
63 flags |= OBJECT_INFO_ALLOW_UNKNOWN_TYPE;
64
65 if (get_sha1_with_context(obj_name, GET_SHA1_RECORD_PATH,
66 oid.hash, &obj_context))
67 die("Not a valid object name %s", obj_name);
68
69 if (!path)
70 path = obj_context.path;
71 if (obj_context.mode == S_IFINVALID)
72 obj_context.mode = 0100644;
73
74 buf = NULL;
75 switch (opt) {
76 case 't':
77 oi.typename = &sb;
78 if (sha1_object_info_extended(oid.hash, &oi, flags) < 0)
79 die("git cat-file: could not get object info");
80 if (sb.len) {
81 printf("%s\n", sb.buf);
82 strbuf_release(&sb);
83 return 0;
84 }
85 break;
86
87 case 's':
88 oi.sizep = &size;
89 if (sha1_object_info_extended(oid.hash, &oi, flags) < 0)
90 die("git cat-file: could not get object info");
91 printf("%lu\n", size);
92 return 0;
93
94 case 'e':
95 return !has_object_file(&oid);
96
97 case 'w':
98 if (!path[0])
99 die("git cat-file --filters %s: <object> must be "
100 "<sha1:path>", obj_name);
101
102 if (filter_object(path, obj_context.mode,
103 &oid, &buf, &size))
104 return -1;
105 break;
106
107 case 'c':
108 if (!path[0])
109 die("git cat-file --textconv %s: <object> must be <sha1:path>",
110 obj_name);
111
112 if (textconv_object(path, obj_context.mode, &oid, 1, &buf, &size))
113 break;
114
115 case 'p':
116 type = sha1_object_info(oid.hash, NULL);
117 if (type < 0)
118 die("Not a valid object name %s", obj_name);
119
120 /* custom pretty-print here */
121 if (type == OBJ_TREE) {
122 const char *ls_args[3] = { NULL };
123 ls_args[0] = "ls-tree";
124 ls_args[1] = obj_name;
125 return cmd_ls_tree(2, ls_args, NULL);
126 }
127
128 if (type == OBJ_BLOB)
129 return stream_blob_to_fd(1, &oid, NULL, 0);
130 buf = read_sha1_file(oid.hash, &type, &size);
131 if (!buf)
132 die("Cannot read object %s", obj_name);
133
134 /* otherwise just spit out the data */
135 break;
136
137 case 0:
138 if (type_from_string(exp_type) == OBJ_BLOB) {
139 struct object_id blob_oid;
140 if (sha1_object_info(oid.hash, NULL) == OBJ_TAG) {
141 char *buffer = read_sha1_file(oid.hash, &type, &size);
142 const char *target;
143 if (!skip_prefix(buffer, "object ", &target) ||
144 get_oid_hex(target, &blob_oid))
145 die("%s not a valid tag", oid_to_hex(&oid));
146 free(buffer);
147 } else
148 oidcpy(&blob_oid, &oid);
149
150 if (sha1_object_info(blob_oid.hash, NULL) == OBJ_BLOB)
151 return stream_blob_to_fd(1, &blob_oid, NULL, 0);
152 /*
153 * we attempted to dereference a tag to a blob
154 * and failed; there may be new dereference
155 * mechanisms this code is not aware of.
156 * fall-back to the usual case.
157 */
158 }
159 buf = read_object_with_reference(oid.hash, exp_type, &size, NULL);
160 break;
161
162 default:
163 die("git cat-file: unknown option: %s", exp_type);
164 }
165
166 if (!buf)
167 die("git cat-file %s: bad file", obj_name);
168
169 write_or_die(1, buf, size);
170 free(buf);
171 free(obj_context.path);
172 return 0;
173}
174
175struct expand_data {
176 struct object_id oid;
177 enum object_type type;
178 unsigned long size;
179 off_t disk_size;
180 const char *rest;
181 struct object_id delta_base_oid;
182
183 /*
184 * If mark_query is true, we do not expand anything, but rather
185 * just mark the object_info with items we wish to query.
186 */
187 int mark_query;
188
189 /*
190 * Whether to split the input on whitespace before feeding it to
191 * get_sha1; this is decided during the mark_query phase based on
192 * whether we have a %(rest) token in our format.
193 */
194 int split_on_whitespace;
195
196 /*
197 * After a mark_query run, this object_info is set up to be
198 * passed to sha1_object_info_extended. It will point to the data
199 * elements above, so you can retrieve the response from there.
200 */
201 struct object_info info;
202
203 /*
204 * This flag will be true if the requested batch format and options
205 * don't require us to call sha1_object_info, which can then be
206 * optimized out.
207 */
208 unsigned skip_object_info : 1;
209};
210
211static int is_atom(const char *atom, const char *s, int slen)
212{
213 int alen = strlen(atom);
214 return alen == slen && !memcmp(atom, s, alen);
215}
216
217static void expand_atom(struct strbuf *sb, const char *atom, int len,
218 void *vdata)
219{
220 struct expand_data *data = vdata;
221
222 if (is_atom("objectname", atom, len)) {
223 if (!data->mark_query)
224 strbuf_addstr(sb, oid_to_hex(&data->oid));
225 } else if (is_atom("objecttype", atom, len)) {
226 if (data->mark_query)
227 data->info.typep = &data->type;
228 else
229 strbuf_addstr(sb, typename(data->type));
230 } else if (is_atom("objectsize", atom, len)) {
231 if (data->mark_query)
232 data->info.sizep = &data->size;
233 else
234 strbuf_addf(sb, "%lu", data->size);
235 } else if (is_atom("objectsize:disk", atom, len)) {
236 if (data->mark_query)
237 data->info.disk_sizep = &data->disk_size;
238 else
239 strbuf_addf(sb, "%"PRIuMAX, (uintmax_t)data->disk_size);
240 } else if (is_atom("rest", atom, len)) {
241 if (data->mark_query)
242 data->split_on_whitespace = 1;
243 else if (data->rest)
244 strbuf_addstr(sb, data->rest);
245 } else if (is_atom("deltabase", atom, len)) {
246 if (data->mark_query)
247 data->info.delta_base_sha1 = data->delta_base_oid.hash;
248 else
249 strbuf_addstr(sb,
250 oid_to_hex(&data->delta_base_oid));
251 } else
252 die("unknown format element: %.*s", len, atom);
253}
254
255static size_t expand_format(struct strbuf *sb, const char *start, void *data)
256{
257 const char *end;
258
259 if (*start != '(')
260 return 0;
261 end = strchr(start + 1, ')');
262 if (!end)
263 die("format element '%s' does not end in ')'", start);
264
265 expand_atom(sb, start + 1, end - start - 1, data);
266
267 return end - start + 1;
268}
269
270static void batch_write(struct batch_options *opt, const void *data, int len)
271{
272 if (opt->buffer_output) {
273 if (fwrite(data, 1, len, stdout) != len)
274 die_errno("unable to write to stdout");
275 } else
276 write_or_die(1, data, len);
277}
278
279static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
280{
281 const struct object_id *oid = &data->oid;
282
283 assert(data->info.typep);
284
285 if (data->type == OBJ_BLOB) {
286 if (opt->buffer_output)
287 fflush(stdout);
288 if (opt->cmdmode) {
289 char *contents;
290 unsigned long size;
291
292 if (!data->rest)
293 die("missing path for '%s'", oid_to_hex(oid));
294
295 if (opt->cmdmode == 'w') {
296 if (filter_object(data->rest, 0100644, oid,
297 &contents, &size))
298 die("could not convert '%s' %s",
299 oid_to_hex(oid), data->rest);
300 } else if (opt->cmdmode == 'c') {
301 enum object_type type;
302 if (!textconv_object(data->rest, 0100644, oid,
303 1, &contents, &size))
304 contents = read_sha1_file(oid->hash, &type,
305 &size);
306 if (!contents)
307 die("could not convert '%s' %s",
308 oid_to_hex(oid), data->rest);
309 } else
310 die("BUG: invalid cmdmode: %c", opt->cmdmode);
311 batch_write(opt, contents, size);
312 free(contents);
313 } else if (stream_blob_to_fd(1, oid, NULL, 0) < 0)
314 die("unable to stream %s to stdout", oid_to_hex(oid));
315 }
316 else {
317 enum object_type type;
318 unsigned long size;
319 void *contents;
320
321 contents = read_sha1_file(oid->hash, &type, &size);
322 if (!contents)
323 die("object %s disappeared", oid_to_hex(oid));
324 if (type != data->type)
325 die("object %s changed type!?", oid_to_hex(oid));
326 if (data->info.sizep && size != data->size)
327 die("object %s changed size!?", oid_to_hex(oid));
328
329 batch_write(opt, contents, size);
330 free(contents);
331 }
332}
333
334static void batch_object_write(const char *obj_name, struct batch_options *opt,
335 struct expand_data *data)
336{
337 struct strbuf buf = STRBUF_INIT;
338
339 if (!data->skip_object_info &&
340 sha1_object_info_extended(data->oid.hash, &data->info,
341 OBJECT_INFO_LOOKUP_REPLACE) < 0) {
342 printf("%s missing\n",
343 obj_name ? obj_name : oid_to_hex(&data->oid));
344 fflush(stdout);
345 return;
346 }
347
348 strbuf_expand(&buf, opt->format, expand_format, data);
349 strbuf_addch(&buf, '\n');
350 batch_write(opt, buf.buf, buf.len);
351 strbuf_release(&buf);
352
353 if (opt->print_contents) {
354 print_object_or_die(opt, data);
355 batch_write(opt, "\n", 1);
356 }
357}
358
359static void batch_one_object(const char *obj_name, struct batch_options *opt,
360 struct expand_data *data)
361{
362 struct object_context ctx;
363 int flags = opt->follow_symlinks ? GET_SHA1_FOLLOW_SYMLINKS : 0;
364 enum follow_symlinks_result result;
365
366 result = get_sha1_with_context(obj_name, flags, data->oid.hash, &ctx);
367 if (result != FOUND) {
368 switch (result) {
369 case MISSING_OBJECT:
370 printf("%s missing\n", obj_name);
371 break;
372 case DANGLING_SYMLINK:
373 printf("dangling %"PRIuMAX"\n%s\n",
374 (uintmax_t)strlen(obj_name), obj_name);
375 break;
376 case SYMLINK_LOOP:
377 printf("loop %"PRIuMAX"\n%s\n",
378 (uintmax_t)strlen(obj_name), obj_name);
379 break;
380 case NOT_DIR:
381 printf("notdir %"PRIuMAX"\n%s\n",
382 (uintmax_t)strlen(obj_name), obj_name);
383 break;
384 default:
385 die("BUG: unknown get_sha1_with_context result %d\n",
386 result);
387 break;
388 }
389 fflush(stdout);
390 return;
391 }
392
393 if (ctx.mode == 0) {
394 printf("symlink %"PRIuMAX"\n%s\n",
395 (uintmax_t)ctx.symlink_path.len,
396 ctx.symlink_path.buf);
397 fflush(stdout);
398 return;
399 }
400
401 batch_object_write(obj_name, opt, data);
402}
403
404struct object_cb_data {
405 struct batch_options *opt;
406 struct expand_data *expand;
407};
408
409static int batch_object_cb(const struct object_id *oid, void *vdata)
410{
411 struct object_cb_data *data = vdata;
412 oidcpy(&data->expand->oid, oid);
413 batch_object_write(NULL, data->opt, data->expand);
414 return 0;
415}
416
417static int batch_loose_object(const struct object_id *oid,
418 const char *path,
419 void *data)
420{
421 oid_array_append(data, oid);
422 return 0;
423}
424
425static int batch_packed_object(const struct object_id *oid,
426 struct packed_git *pack,
427 uint32_t pos,
428 void *data)
429{
430 oid_array_append(data, oid);
431 return 0;
432}
433
434static int batch_objects(struct batch_options *opt)
435{
436 struct strbuf buf = STRBUF_INIT;
437 struct expand_data data;
438 int save_warning;
439 int retval = 0;
440
441 if (!opt->format)
442 opt->format = "%(objectname) %(objecttype) %(objectsize)";
443
444 /*
445 * Expand once with our special mark_query flag, which will prime the
446 * object_info to be handed to sha1_object_info_extended for each
447 * object.
448 */
449 memset(&data, 0, sizeof(data));
450 data.mark_query = 1;
451 strbuf_expand(&buf, opt->format, expand_format, &data);
452 data.mark_query = 0;
453 if (opt->cmdmode)
454 data.split_on_whitespace = 1;
455
456 if (opt->all_objects) {
457 struct object_info empty = OBJECT_INFO_INIT;
458 if (!memcmp(&data.info, &empty, sizeof(empty)))
459 data.skip_object_info = 1;
460 }
461
462 /*
463 * If we are printing out the object, then always fill in the type,
464 * since we will want to decide whether or not to stream.
465 */
466 if (opt->print_contents)
467 data.info.typep = &data.type;
468
469 if (opt->all_objects) {
470 struct oid_array sa = OID_ARRAY_INIT;
471 struct object_cb_data cb;
472
473 for_each_loose_object(batch_loose_object, &sa, 0);
474 for_each_packed_object(batch_packed_object, &sa, 0);
475
476 cb.opt = opt;
477 cb.expand = &data;
478 oid_array_for_each_unique(&sa, batch_object_cb, &cb);
479
480 oid_array_clear(&sa);
481 return 0;
482 }
483
484 /*
485 * We are going to call get_sha1 on a potentially very large number of
486 * objects. In most large cases, these will be actual object sha1s. The
487 * cost to double-check that each one is not also a ref (just so we can
488 * warn) ends up dwarfing the actual cost of the object lookups
489 * themselves. We can work around it by just turning off the warning.
490 */
491 save_warning = warn_on_object_refname_ambiguity;
492 warn_on_object_refname_ambiguity = 0;
493
494 while (strbuf_getline(&buf, stdin) != EOF) {
495 if (data.split_on_whitespace) {
496 /*
497 * Split at first whitespace, tying off the beginning
498 * of the string and saving the remainder (or NULL) in
499 * data.rest.
500 */
501 char *p = strpbrk(buf.buf, " \t");
502 if (p) {
503 while (*p && strchr(" \t", *p))
504 *p++ = '\0';
505 }
506 data.rest = p;
507 }
508
509 batch_one_object(buf.buf, opt, &data);
510 }
511
512 strbuf_release(&buf);
513 warn_on_object_refname_ambiguity = save_warning;
514 return retval;
515}
516
517static const char * const cat_file_usage[] = {
518 N_("git cat-file (-t [--allow-unknown-type] | -s [--allow-unknown-type] | -e | -p | <type> | --textconv | --filters) [--path=<path>] <object>"),
519 N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv | --filters]"),
520 NULL
521};
522
523static int git_cat_file_config(const char *var, const char *value, void *cb)
524{
525 if (userdiff_config(var, value) < 0)
526 return -1;
527
528 return git_default_config(var, value, cb);
529}
530
531static int batch_option_callback(const struct option *opt,
532 const char *arg,
533 int unset)
534{
535 struct batch_options *bo = opt->value;
536
537 if (bo->enabled) {
538 return 1;
539 }
540
541 bo->enabled = 1;
542 bo->print_contents = !strcmp(opt->long_name, "batch");
543 bo->format = arg;
544
545 return 0;
546}
547
548int cmd_cat_file(int argc, const char **argv, const char *prefix)
549{
550 int opt = 0;
551 const char *exp_type = NULL, *obj_name = NULL;
552 struct batch_options batch = {0};
553 int unknown_type = 0;
554
555 const struct option options[] = {
556 OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
557 OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
558 OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
559 OPT_CMDMODE('e', NULL, &opt,
560 N_("exit with zero when there's no error"), 'e'),
561 OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
562 OPT_CMDMODE(0, "textconv", &opt,
563 N_("for blob objects, run textconv on object's content"), 'c'),
564 OPT_CMDMODE(0, "filters", &opt,
565 N_("for blob objects, run filters on object's content"), 'w'),
566 OPT_STRING(0, "path", &force_path, N_("blob"),
567 N_("use a specific path for --textconv/--filters")),
568 OPT_BOOL(0, "allow-unknown-type", &unknown_type,
569 N_("allow -s and -t to work with broken/corrupt objects")),
570 OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
571 { OPTION_CALLBACK, 0, "batch", &batch, "format",
572 N_("show info and content of objects fed from the standard input"),
573 PARSE_OPT_OPTARG, batch_option_callback },
574 { OPTION_CALLBACK, 0, "batch-check", &batch, "format",
575 N_("show info about objects fed from the standard input"),
576 PARSE_OPT_OPTARG, batch_option_callback },
577 OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
578 N_("follow in-tree symlinks (used with --batch or --batch-check)")),
579 OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
580 N_("show all objects with --batch or --batch-check")),
581 OPT_END()
582 };
583
584 git_config(git_cat_file_config, NULL);
585
586 batch.buffer_output = -1;
587 argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
588
589 if (opt) {
590 if (batch.enabled && (opt == 'c' || opt == 'w'))
591 batch.cmdmode = opt;
592 else if (argc == 1)
593 obj_name = argv[0];
594 else
595 usage_with_options(cat_file_usage, options);
596 }
597 if (!opt && !batch.enabled) {
598 if (argc == 2) {
599 exp_type = argv[0];
600 obj_name = argv[1];
601 } else
602 usage_with_options(cat_file_usage, options);
603 }
604 if (batch.enabled) {
605 if (batch.cmdmode != opt || argc)
606 usage_with_options(cat_file_usage, options);
607 if (batch.cmdmode && batch.all_objects)
608 die("--batch-all-objects cannot be combined with "
609 "--textconv nor with --filters");
610 }
611
612 if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
613 usage_with_options(cat_file_usage, options);
614 }
615
616 if (force_path && opt != 'c' && opt != 'w') {
617 error("--path=<path> needs --textconv or --filters");
618 usage_with_options(cat_file_usage, options);
619 }
620
621 if (force_path && batch.enabled) {
622 error("--path=<path> incompatible with --batch");
623 usage_with_options(cat_file_usage, options);
624 }
625
626 if (batch.buffer_output < 0)
627 batch.buffer_output = batch.all_objects;
628
629 if (batch.enabled)
630 return batch_objects(&batch);
631
632 if (unknown_type && opt != 't' && opt != 's')
633 die("git cat-file --allow-unknown-type: use with -s or -t");
634 return cat_one_file(opt, exp_type, obj_name, unknown_type);
635}