checkout: refer to other-worktree branch, not ref
[git/gitster.git] / archive.c
bloba7a92ff83937f86b3ec5c2c3f2d68f9b8cdbf6f1
1 #define USE_THE_REPOSITORY_VARIABLE
3 #include "git-compat-util.h"
4 #include "abspath.h"
5 #include "config.h"
6 #include "convert.h"
7 #include "environment.h"
8 #include "gettext.h"
9 #include "hex.h"
10 #include "object-name.h"
11 #include "path.h"
12 #include "pretty.h"
13 #include "setup.h"
14 #include "refs.h"
15 #include "object-store-ll.h"
16 #include "commit.h"
17 #include "tree.h"
18 #include "tree-walk.h"
19 #include "attr.h"
20 #include "archive.h"
21 #include "parse-options.h"
22 #include "unpack-trees.h"
23 #include "quote.h"
25 static char const * const archive_usage[] = {
26 N_("git archive [<options>] <tree-ish> [<path>...]"),
27 "git archive --list",
28 N_("git archive --remote <repo> [--exec <cmd>] [<options>] <tree-ish> [<path>...]"),
29 N_("git archive --remote <repo> [--exec <cmd>] --list"),
30 NULL
33 static const struct archiver **archivers;
34 static int nr_archivers;
35 static int alloc_archivers;
36 static int remote_allow_unreachable;
38 void register_archiver(struct archiver *ar)
40 ALLOC_GROW(archivers, nr_archivers + 1, alloc_archivers);
41 archivers[nr_archivers++] = ar;
44 void init_archivers(void)
46 init_tar_archiver();
47 init_zip_archiver();
50 static void format_subst(const struct commit *commit,
51 const char *src, size_t len,
52 struct strbuf *buf, struct pretty_print_context *ctx)
54 char *to_free = NULL;
55 struct strbuf fmt = STRBUF_INIT;
57 if (src == buf->buf)
58 to_free = strbuf_detach(buf, NULL);
59 for (;;) {
60 const char *b, *c;
62 b = memmem(src, len, "$Format:", 8);
63 if (!b)
64 break;
65 c = memchr(b + 8, '$', (src + len) - b - 8);
66 if (!c)
67 break;
69 strbuf_reset(&fmt);
70 strbuf_add(&fmt, b + 8, c - b - 8);
72 strbuf_add(buf, src, b - src);
73 repo_format_commit_message(the_repository, commit, fmt.buf,
74 buf, ctx);
75 len -= c + 1 - src;
76 src = c + 1;
78 strbuf_add(buf, src, len);
79 strbuf_release(&fmt);
80 free(to_free);
83 static void *object_file_to_archive(const struct archiver_args *args,
84 const char *path,
85 const struct object_id *oid,
86 unsigned int mode,
87 enum object_type *type,
88 unsigned long *sizep)
90 void *buffer;
91 const struct commit *commit = args->convert ? args->commit : NULL;
92 struct checkout_metadata meta;
94 init_checkout_metadata(&meta, args->refname,
95 args->commit_oid ? args->commit_oid :
96 (args->tree ? &args->tree->object.oid : NULL), oid);
98 path += args->baselen;
99 buffer = repo_read_object_file(the_repository, oid, type, sizep);
100 if (buffer && S_ISREG(mode)) {
101 struct strbuf buf = STRBUF_INIT;
102 size_t size = 0;
104 strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
105 convert_to_working_tree(args->repo->index, path, buf.buf, buf.len, &buf, &meta);
106 if (commit)
107 format_subst(commit, buf.buf, buf.len, &buf, args->pretty_ctx);
108 buffer = strbuf_detach(&buf, &size);
109 *sizep = size;
112 return buffer;
115 struct directory {
116 struct directory *up;
117 struct object_id oid;
118 int baselen, len;
119 unsigned mode;
120 char path[FLEX_ARRAY];
123 struct archiver_context {
124 struct archiver_args *args;
125 write_archive_entry_fn_t write_entry;
126 struct directory *bottom;
129 static const struct attr_check *get_archive_attrs(struct index_state *istate,
130 const char *path)
132 static struct attr_check *check;
133 if (!check)
134 check = attr_check_initl("export-ignore", "export-subst", NULL);
135 git_check_attr(istate, path, check);
136 return check;
139 static int check_attr_export_ignore(const struct attr_check *check)
141 return check && ATTR_TRUE(check->items[0].value);
144 static int check_attr_export_subst(const struct attr_check *check)
146 return check && ATTR_TRUE(check->items[1].value);
149 static int write_archive_entry(const struct object_id *oid, const char *base,
150 int baselen, const char *filename, unsigned mode,
151 void *context)
153 static struct strbuf path = STRBUF_INIT;
154 struct archiver_context *c = context;
155 struct archiver_args *args = c->args;
156 write_archive_entry_fn_t write_entry = c->write_entry;
157 int err;
158 const char *path_without_prefix;
159 unsigned long size;
160 void *buffer;
161 enum object_type type;
163 args->convert = 0;
164 strbuf_reset(&path);
165 strbuf_grow(&path, PATH_MAX);
166 strbuf_add(&path, args->base, args->baselen);
167 strbuf_add(&path, base, baselen);
168 strbuf_addstr(&path, filename);
169 if (S_ISDIR(mode) || S_ISGITLINK(mode))
170 strbuf_addch(&path, '/');
171 path_without_prefix = path.buf + args->baselen;
173 if (!S_ISDIR(mode)) {
174 const struct attr_check *check;
175 check = get_archive_attrs(args->repo->index, path_without_prefix);
176 if (check_attr_export_ignore(check))
177 return 0;
178 args->convert = check_attr_export_subst(check);
181 if (args->prefix) {
182 static struct strbuf new_path = STRBUF_INIT;
183 static struct strbuf buf = STRBUF_INIT;
184 const char *rel;
186 rel = relative_path(path_without_prefix, args->prefix, &buf);
189 * We don't add an entry for the current working
190 * directory when we are at the root; skip it also when
191 * we're in a subdirectory or submodule. Skip entries
192 * higher up as well.
194 if (!strcmp(rel, "./") || starts_with(rel, "../"))
195 return S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0;
197 /* rel can refer to path, so don't edit it in place */
198 strbuf_reset(&new_path);
199 strbuf_add(&new_path, args->base, args->baselen);
200 strbuf_addstr(&new_path, rel);
201 strbuf_swap(&path, &new_path);
204 if (args->verbose)
205 fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
207 if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
208 err = write_entry(args, oid, path.buf, path.len, mode, NULL, 0);
209 if (err)
210 return err;
211 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
214 /* Stream it? */
215 if (S_ISREG(mode) && !args->convert &&
216 oid_object_info(args->repo, oid, &size) == OBJ_BLOB &&
217 size > big_file_threshold)
218 return write_entry(args, oid, path.buf, path.len, mode, NULL, size);
220 buffer = object_file_to_archive(args, path.buf, oid, mode, &type, &size);
221 if (!buffer)
222 return error(_("cannot read '%s'"), oid_to_hex(oid));
223 err = write_entry(args, oid, path.buf, path.len, mode, buffer, size);
224 free(buffer);
225 return err;
228 static void queue_directory(const struct object_id *oid,
229 struct strbuf *base, const char *filename,
230 unsigned mode, struct archiver_context *c)
232 struct directory *d;
233 size_t len = st_add4(base->len, 1, strlen(filename), 1);
234 d = xmalloc(st_add(sizeof(*d), len));
235 d->up = c->bottom;
236 d->baselen = base->len;
237 d->mode = mode;
238 c->bottom = d;
239 d->len = xsnprintf(d->path, len, "%.*s%s/", (int)base->len, base->buf, filename);
240 oidcpy(&d->oid, oid);
243 static int write_directory(struct archiver_context *c)
245 struct directory *d = c->bottom;
246 int ret;
248 if (!d)
249 return 0;
250 c->bottom = d->up;
251 d->path[d->len - 1] = '\0'; /* no trailing slash */
252 ret =
253 write_directory(c) ||
254 write_archive_entry(&d->oid, d->path, d->baselen,
255 d->path + d->baselen, d->mode,
256 c) != READ_TREE_RECURSIVE;
257 free(d);
258 return ret ? -1 : 0;
261 static int queue_or_write_archive_entry(const struct object_id *oid,
262 struct strbuf *base, const char *filename,
263 unsigned mode, void *context)
265 struct archiver_context *c = context;
267 while (c->bottom &&
268 !(base->len >= c->bottom->len &&
269 !strncmp(base->buf, c->bottom->path, c->bottom->len))) {
270 struct directory *next = c->bottom->up;
271 free(c->bottom);
272 c->bottom = next;
275 if (S_ISDIR(mode)) {
276 size_t baselen = base->len;
277 const struct attr_check *check;
279 /* Borrow base, but restore its original value when done. */
280 strbuf_addstr(base, filename);
281 strbuf_addch(base, '/');
282 check = get_archive_attrs(c->args->repo->index, base->buf);
283 strbuf_setlen(base, baselen);
285 if (check_attr_export_ignore(check))
286 return 0;
287 queue_directory(oid, base, filename, mode, c);
288 return READ_TREE_RECURSIVE;
291 if (write_directory(c))
292 return -1;
293 return write_archive_entry(oid, base->buf, base->len, filename, mode,
294 context);
297 struct extra_file_info {
298 char *base;
299 struct stat stat;
300 void *content;
303 int write_archive_entries(struct archiver_args *args,
304 write_archive_entry_fn_t write_entry)
306 struct archiver_context context;
307 int err;
308 struct strbuf path_in_archive = STRBUF_INIT;
309 struct strbuf content = STRBUF_INIT;
310 struct object_id fake_oid;
311 int i;
313 oidcpy(&fake_oid, null_oid());
315 if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
316 size_t len = args->baselen;
318 while (len > 1 && args->base[len - 2] == '/')
319 len--;
320 if (args->verbose)
321 fprintf(stderr, "%.*s\n", (int)len, args->base);
322 err = write_entry(args, &args->tree->object.oid, args->base,
323 len, 040777, NULL, 0);
324 if (err)
325 return err;
328 memset(&context, 0, sizeof(context));
329 context.args = args;
330 context.write_entry = write_entry;
332 err = read_tree(args->repo, args->tree,
333 &args->pathspec,
334 queue_or_write_archive_entry,
335 &context);
336 if (err == READ_TREE_RECURSIVE)
337 err = 0;
338 while (context.bottom) {
339 struct directory *next = context.bottom->up;
340 free(context.bottom);
341 context.bottom = next;
344 for (i = 0; i < args->extra_files.nr; i++) {
345 struct string_list_item *item = args->extra_files.items + i;
346 char *path = item->string;
347 struct extra_file_info *info = item->util;
349 put_be64(fake_oid.hash, i + 1);
351 if (!info->content) {
352 strbuf_reset(&path_in_archive);
353 if (info->base)
354 strbuf_addstr(&path_in_archive, info->base);
355 strbuf_addstr(&path_in_archive, basename(path));
357 strbuf_reset(&content);
358 if (strbuf_read_file(&content, path, info->stat.st_size) < 0)
359 err = error_errno(_("cannot read '%s'"), path);
360 else
361 err = write_entry(args, &fake_oid, path_in_archive.buf,
362 path_in_archive.len,
363 canon_mode(info->stat.st_mode),
364 content.buf, content.len);
365 } else {
366 err = write_entry(args, &fake_oid,
367 path, strlen(path),
368 canon_mode(info->stat.st_mode),
369 info->content, info->stat.st_size);
372 if (err)
373 break;
375 strbuf_release(&path_in_archive);
376 strbuf_release(&content);
378 return err;
381 static const struct archiver *lookup_archiver(const char *name)
383 int i;
385 if (!name)
386 return NULL;
388 for (i = 0; i < nr_archivers; i++) {
389 if (!strcmp(name, archivers[i]->name))
390 return archivers[i];
392 return NULL;
395 struct path_exists_context {
396 struct pathspec pathspec;
397 struct archiver_args *args;
400 static int reject_entry(const struct object_id *oid UNUSED,
401 struct strbuf *base,
402 const char *filename, unsigned mode,
403 void *context)
405 int ret = -1;
406 struct path_exists_context *ctx = context;
408 if (S_ISDIR(mode)) {
409 struct strbuf sb = STRBUF_INIT;
410 strbuf_addbuf(&sb, base);
411 strbuf_addstr(&sb, filename);
412 if (!match_pathspec(ctx->args->repo->index,
413 &ctx->pathspec,
414 sb.buf, sb.len, 0, NULL, 1))
415 ret = READ_TREE_RECURSIVE;
416 strbuf_release(&sb);
418 return ret;
421 static int reject_outside(const struct object_id *oid UNUSED,
422 struct strbuf *base, const char *filename,
423 unsigned mode, void *context)
425 struct archiver_args *args = context;
426 struct strbuf buf = STRBUF_INIT;
427 struct strbuf path = STRBUF_INIT;
428 int ret = 0;
430 if (S_ISDIR(mode))
431 return READ_TREE_RECURSIVE;
433 strbuf_addbuf(&path, base);
434 strbuf_addstr(&path, filename);
435 if (starts_with(relative_path(path.buf, args->prefix, &buf), "../"))
436 ret = -1;
437 strbuf_release(&buf);
438 strbuf_release(&path);
439 return ret;
442 static int path_exists(struct archiver_args *args, const char *path)
444 const char *paths[] = { path, NULL };
445 struct path_exists_context ctx;
446 int ret;
448 ctx.args = args;
449 parse_pathspec(&ctx.pathspec, 0, PATHSPEC_PREFER_CWD,
450 args->prefix, paths);
451 ctx.pathspec.recursive = 1;
452 if (args->prefix && read_tree(args->repo, args->tree, &ctx.pathspec,
453 reject_outside, args))
454 die(_("pathspec '%s' matches files outside the "
455 "current directory"), path);
456 ret = read_tree(args->repo, args->tree,
457 &ctx.pathspec,
458 reject_entry, &ctx);
459 clear_pathspec(&ctx.pathspec);
460 return ret != 0;
463 static void parse_pathspec_arg(const char **pathspec,
464 struct archiver_args *ar_args)
467 * must be consistent with parse_pathspec in path_exists()
468 * Also if pathspec patterns are dependent, we're in big
469 * trouble as we test each one separately
471 parse_pathspec(&ar_args->pathspec, 0, PATHSPEC_PREFER_CWD,
472 ar_args->prefix, pathspec);
473 ar_args->pathspec.recursive = 1;
474 if (pathspec) {
475 while (*pathspec) {
476 if (**pathspec && !path_exists(ar_args, *pathspec))
477 die(_("pathspec '%s' did not match any files"), *pathspec);
478 pathspec++;
483 static void parse_treeish_arg(const char **argv,
484 struct archiver_args *ar_args, int remote)
486 const char *name = argv[0];
487 const struct object_id *commit_oid;
488 time_t archive_time;
489 struct tree *tree;
490 const struct commit *commit;
491 struct object_id oid;
492 char *ref = NULL;
494 /* Remotes are only allowed to fetch actual refs */
495 if (remote && !remote_allow_unreachable) {
496 const char *colon = strchrnul(name, ':');
497 int refnamelen = colon - name;
499 if (!repo_dwim_ref(the_repository, name, refnamelen, &oid, &ref, 0))
500 die(_("no such ref: %.*s"), refnamelen, name);
501 } else {
502 repo_dwim_ref(the_repository, name, strlen(name), &oid, &ref,
506 if (repo_get_oid(the_repository, name, &oid))
507 die(_("not a valid object name: %s"), name);
509 commit = lookup_commit_reference_gently(ar_args->repo, &oid, 1);
510 if (commit) {
511 commit_oid = &commit->object.oid;
512 archive_time = commit->date;
513 } else {
514 commit_oid = NULL;
515 archive_time = time(NULL);
517 if (ar_args->mtime_option)
518 archive_time = approxidate(ar_args->mtime_option);
520 tree = parse_tree_indirect(&oid);
521 if (!tree)
522 die(_("not a tree object: %s"), oid_to_hex(&oid));
525 * Setup index and instruct attr to read index only
527 if (!ar_args->worktree_attributes) {
528 struct unpack_trees_options opts;
529 struct tree_desc t;
531 memset(&opts, 0, sizeof(opts));
532 opts.index_only = 1;
533 opts.head_idx = -1;
534 opts.src_index = ar_args->repo->index;
535 opts.dst_index = ar_args->repo->index;
536 opts.fn = oneway_merge;
537 init_tree_desc(&t, &tree->object.oid, tree->buffer, tree->size);
538 if (unpack_trees(1, &t, &opts))
539 die(_("failed to unpack tree object %s"),
540 oid_to_hex(&tree->object.oid));
542 git_attr_set_direction(GIT_ATTR_INDEX);
545 ar_args->refname = ref;
546 ar_args->tree = tree;
547 ar_args->commit_oid = commit_oid;
548 ar_args->commit = commit;
549 ar_args->time = archive_time;
552 static void extra_file_info_clear(void *util, const char *str UNUSED)
554 struct extra_file_info *info = util;
555 free(info->base);
556 free(info->content);
557 free(info);
560 static int add_file_cb(const struct option *opt, const char *arg, int unset)
562 struct archiver_args *args = opt->value;
563 const char **basep = (const char **)opt->defval;
564 const char *base = *basep;
565 char *path;
566 struct string_list_item *item;
567 struct extra_file_info *info;
569 if (unset) {
570 string_list_clear_func(&args->extra_files,
571 extra_file_info_clear);
572 return 0;
575 if (!arg)
576 return -1;
578 info = xmalloc(sizeof(*info));
579 info->base = xstrdup_or_null(base);
581 if (!strcmp(opt->long_name, "add-file")) {
582 path = prefix_filename(args->prefix, arg);
583 if (stat(path, &info->stat))
584 die(_("File not found: %s"), path);
585 if (!S_ISREG(info->stat.st_mode))
586 die(_("Not a regular file: %s"), path);
587 info->content = NULL; /* read the file later */
588 } else if (!strcmp(opt->long_name, "add-virtual-file")) {
589 struct strbuf buf = STRBUF_INIT;
590 const char *p = arg;
592 if (*p != '"')
593 p = strchr(p, ':');
594 else if (unquote_c_style(&buf, p, &p) < 0)
595 die(_("unclosed quote: '%s'"), arg);
597 if (!p || *p != ':')
598 die(_("missing colon: '%s'"), arg);
600 if (p == arg)
601 die(_("empty file name: '%s'"), arg);
603 path = buf.len ?
604 strbuf_detach(&buf, NULL) : xstrndup(arg, p - arg);
606 if (args->prefix) {
607 char *save = path;
608 path = prefix_filename(args->prefix, path);
609 free(save);
611 memset(&info->stat, 0, sizeof(info->stat));
612 info->stat.st_mode = S_IFREG | 0644;
613 info->content = xstrdup(p + 1);
614 info->stat.st_size = strlen(info->content);
615 } else {
616 BUG("add_file_cb() called for %s", opt->long_name);
618 item = string_list_append_nodup(&args->extra_files, path);
619 item->util = info;
621 return 0;
624 static int number_callback(const struct option *opt, const char *arg, int unset)
626 BUG_ON_OPT_NEG(unset);
627 *(int *)opt->value = strtol(arg, NULL, 10);
628 return 0;
631 static int parse_archive_args(int argc, const char **argv,
632 const struct archiver **ar, struct archiver_args *args,
633 const char *name_hint, int is_remote)
635 const char *format = NULL;
636 const char *base = NULL;
637 const char *remote = NULL;
638 const char *exec = NULL;
639 const char *output = NULL;
640 const char *mtime_option = NULL;
641 int compression_level = -1;
642 int verbose = 0;
643 int i;
644 int list = 0;
645 int worktree_attributes = 0;
646 struct option opts[] = {
647 OPT_GROUP(""),
648 OPT_STRING(0, "format", &format, N_("fmt"), N_("archive format")),
649 OPT_STRING(0, "prefix", &base, N_("prefix"),
650 N_("prepend prefix to each pathname in the archive")),
651 { OPTION_CALLBACK, 0, "add-file", args, N_("file"),
652 N_("add untracked file to archive"), 0, add_file_cb,
653 (intptr_t)&base },
654 { OPTION_CALLBACK, 0, "add-virtual-file", args,
655 N_("path:content"), N_("add untracked file to archive"), 0,
656 add_file_cb, (intptr_t)&base },
657 OPT_STRING('o', "output", &output, N_("file"),
658 N_("write the archive to this file")),
659 OPT_BOOL(0, "worktree-attributes", &worktree_attributes,
660 N_("read .gitattributes in working directory")),
661 OPT__VERBOSE(&verbose, N_("report archived files on stderr")),
662 { OPTION_STRING, 0, "mtime", &mtime_option, N_("time"),
663 N_("set modification time of archive entries"),
664 PARSE_OPT_NONEG },
665 OPT_NUMBER_CALLBACK(&compression_level,
666 N_("set compression level"), number_callback),
667 OPT_GROUP(""),
668 OPT_BOOL('l', "list", &list,
669 N_("list supported archive formats")),
670 OPT_GROUP(""),
671 OPT_STRING(0, "remote", &remote, N_("repo"),
672 N_("retrieve the archive from remote repository <repo>")),
673 OPT_STRING(0, "exec", &exec, N_("command"),
674 N_("path to the remote git-upload-archive command")),
675 OPT_END()
678 argc = parse_options(argc, argv, NULL, opts, archive_usage, 0);
680 if (remote)
681 die(_("Unexpected option --remote"));
682 if (exec)
683 die(_("the option '%s' requires '%s'"), "--exec", "--remote");
684 if (output)
685 die(_("Unexpected option --output"));
686 if (is_remote && args->extra_files.nr)
687 die(_("options '%s' and '%s' cannot be used together"), "--add-file", "--remote");
689 if (!base)
690 base = "";
692 if (list) {
693 if (argc)
694 die(_("extra command line parameter '%s'"), *argv);
695 for (i = 0; i < nr_archivers; i++)
696 if (!is_remote || archivers[i]->flags & ARCHIVER_REMOTE)
697 printf("%s\n", archivers[i]->name);
698 exit(0);
701 if (!format && name_hint)
702 format = archive_format_from_filename(name_hint);
703 if (!format)
704 format = "tar";
706 /* We need at least one parameter -- tree-ish */
707 if (argc < 1)
708 usage_with_options(archive_usage, opts);
709 *ar = lookup_archiver(format);
710 if (!*ar || (is_remote && !((*ar)->flags & ARCHIVER_REMOTE)))
711 die(_("Unknown archive format '%s'"), format);
713 args->compression_level = Z_DEFAULT_COMPRESSION;
714 if (compression_level != -1) {
715 int levels_ok = (*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS;
716 int high_ok = (*ar)->flags & ARCHIVER_HIGH_COMPRESSION_LEVELS;
717 if (levels_ok && (compression_level <= 9 || high_ok))
718 args->compression_level = compression_level;
719 else {
720 die(_("Argument not supported for format '%s': -%d"),
721 format, compression_level);
724 args->verbose = verbose;
725 args->base = base;
726 args->baselen = strlen(base);
727 args->worktree_attributes = worktree_attributes;
728 args->mtime_option = mtime_option;
730 return argc;
733 int write_archive(int argc, const char **argv, const char *prefix,
734 struct repository *repo,
735 const char *name_hint, int remote)
737 const struct archiver *ar = NULL;
738 struct pretty_print_describe_status describe_status = {0};
739 struct pretty_print_context ctx = {0};
740 struct archiver_args args;
741 const char **argv_copy;
742 int rc;
744 git_config_get_bool("uploadarchive.allowunreachable", &remote_allow_unreachable);
745 git_config(git_default_config, NULL);
747 describe_status.max_invocations = 1;
748 ctx.date_mode.type = DATE_NORMAL;
749 ctx.abbrev = DEFAULT_ABBREV;
750 ctx.describe_status = &describe_status;
751 args.pretty_ctx = &ctx;
752 args.repo = repo;
753 args.prefix = prefix;
754 string_list_init_dup(&args.extra_files);
757 * `parse_archive_args()` modifies contents of `argv`, which is what we
758 * want. Our callers may not want it though, so we create a copy here.
760 DUP_ARRAY(argv_copy, argv, argc);
761 argv = argv_copy;
763 argc = parse_archive_args(argc, argv, &ar, &args, name_hint, remote);
764 if (!startup_info->have_repository) {
766 * We know this will die() with an error, so we could just
767 * die ourselves; but its error message will be more specific
768 * than what we could write here.
770 setup_git_directory();
773 parse_treeish_arg(argv, &args, remote);
774 parse_pathspec_arg(argv + 1, &args);
776 rc = ar->write_archive(ar, &args);
778 string_list_clear_func(&args.extra_files, extra_file_info_clear);
779 free(args.refname);
780 clear_pathspec(&args.pathspec);
781 free(argv_copy);
783 return rc;
786 static int match_extension(const char *filename, const char *ext)
788 int prefixlen = strlen(filename) - strlen(ext);
791 * We need 1 character for the '.', and 1 character to ensure that the
792 * prefix is non-empty (k.e., we don't match .tar.gz with no actual
793 * filename).
795 if (prefixlen < 2 || filename[prefixlen - 1] != '.')
796 return 0;
797 return !strcmp(filename + prefixlen, ext);
800 const char *archive_format_from_filename(const char *filename)
802 int i;
804 for (i = 0; i < nr_archivers; i++)
805 if (match_extension(filename, archivers[i]->name))
806 return archivers[i]->name;
807 return NULL;