archive.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "refs.h"
   4 #include "object-store.h"
   5 #include "commit.h"
   6 #include "tree-walk.h"
   7 #include "attr.h"
   8 #include "archive.h"
   9 #include "parse-options.h"
  10 #include "unpack-trees.h"
  11 #include "dir.h"
  12 #include "quote.h"
  13
  14 static char const * const archive_usage[] = {
  15         N_("git archive [<options>] <tree-ish> [<path>...]"),
  16         "git archive --list",
  17         N_("git archive --remote <repo> [--exec <cmd>] [<options>] <tree-ish> [<path>...]"),
  18         N_("git archive --remote <repo> [--exec <cmd>] --list"),
  19         NULL
  20 };
  21
  22 static const struct archiver **archivers;
  23 static int nr_archivers;
  24 static int alloc_archivers;
  25 static int remote_allow_unreachable;
  26
  27 void register_archiver(struct archiver *ar)
  28 {
  29         ALLOC_GROW(archivers, nr_archivers + 1, alloc_archivers);
  30         archivers[nr_archivers++] = ar;
  31 }
  32
  33 void init_archivers(void)
  34 {
  35         init_tar_archiver();
  36         init_zip_archiver();
  37 }
  38
  39 static void format_subst(const struct commit *commit,
  40                          const char *src, size_t len,
  41                          struct strbuf *buf, struct pretty_print_context *ctx)
  42 {
  43         char *to_free = NULL;
  44         struct strbuf fmt = STRBUF_INIT;
  45
  46         if (src == buf->buf)
  47                 to_free = strbuf_detach(buf, NULL);
  48         for (;;) {
  49                 const char *b, *c;
  50
  51                 b = memmem(src, len, "$Format:", 8);
  52                 if (!b)
  53                         break;
  54                 c = memchr(b + 8, '$', (src + len) - b - 8);
  55                 if (!c)
  56                         break;
  57
  58                 strbuf_reset(&fmt);
  59                 strbuf_add(&fmt, b + 8, c - b - 8);
  60
  61                 strbuf_add(buf, src, b - src);
  62                 format_commit_message(commit, fmt.buf, buf, ctx);
  63                 len -= c + 1 - src;
  64                 src  = c + 1;
  65         }
  66         strbuf_add(buf, src, len);
  67         strbuf_release(&fmt);
  68         free(to_free);
  69 }
  70
  71 static void *object_file_to_archive(const struct archiver_args *args,
  72                                     const char *path,
  73                                     const struct object_id *oid,
  74                                     unsigned int mode,
  75                                     enum object_type *type,
  76                                     unsigned long *sizep)
  77 {
  78         void *buffer;
  79         const struct commit *commit = args->convert ? args->commit : NULL;
  80         struct checkout_metadata meta;
  81
  82         init_checkout_metadata(&meta, args->refname,
  83                                args->commit_oid ? args->commit_oid :
  84                                (args->tree ? &args->tree->object.oid : NULL), oid);
  85
  86         path += args->baselen;
  87         buffer = read_object_file(oid, type, sizep);
  88         if (buffer && S_ISREG(mode)) {
  89                 struct strbuf buf = STRBUF_INIT;
  90                 size_t size = 0;
  91
  92                 strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
  93                 convert_to_working_tree(args->repo->index, path, buf.buf, buf.len, &buf, &meta);
  94                 if (commit)
  95                         format_subst(commit, buf.buf, buf.len, &buf, args->pretty_ctx);
  96                 buffer = strbuf_detach(&buf, &size);
  97                 *sizep = size;
  98         }
  99
 100         return buffer;
 101 }
 102
 103 struct directory {
 104         struct directory *up;
 105         struct object_id oid;
 106         int baselen, len;
 107         unsigned mode;
 108         char path[FLEX_ARRAY];
 109 };
 110
 111 struct archiver_context {
 112         struct archiver_args *args;
 113         write_archive_entry_fn_t write_entry;
 114         struct directory *bottom;
 115 };
 116
 117 static const struct attr_check *get_archive_attrs(struct index_state *istate,
 118                                                   const char *path)
 119 {
 120         static struct attr_check *check;
 121         if (!check)
 122                 check = attr_check_initl("export-ignore", "export-subst", NULL);
 123         git_check_attr(istate, path, check);
 124         return check;
 125 }
 126
 127 static int check_attr_export_ignore(const struct attr_check *check)
 128 {
 129         return check && ATTR_TRUE(check->items[0].value);
 130 }
 131
 132 static int check_attr_export_subst(const struct attr_check *check)
 133 {
 134         return check && ATTR_TRUE(check->items[1].value);
 135 }
 136
 137 static int write_archive_entry(const struct object_id *oid, const char *base,
 138                 int baselen, const char *filename, unsigned mode,
 139                 void *context)
 140 {
 141         static struct strbuf path = STRBUF_INIT;
 142         struct archiver_context *c = context;
 143         struct archiver_args *args = c->args;
 144         write_archive_entry_fn_t write_entry = c->write_entry;
 145         int err;
 146         const char *path_without_prefix;
 147         unsigned long size;
 148         void *buffer;
 149         enum object_type type;
 150
 151         args->convert = 0;
 152         strbuf_reset(&path);
 153         strbuf_grow(&path, PATH_MAX);
 154         strbuf_add(&path, args->base, args->baselen);
 155         strbuf_add(&path, base, baselen);
 156         strbuf_addstr(&path, filename);
 157         if (S_ISDIR(mode) || S_ISGITLINK(mode))
 158                 strbuf_addch(&path, '/');
 159         path_without_prefix = path.buf + args->baselen;
 160
 161         if (!S_ISDIR(mode)) {
 162                 const struct attr_check *check;
 163                 check = get_archive_attrs(args->repo->index, path_without_prefix);
 164                 if (check_attr_export_ignore(check))
 165                         return 0;
 166                 args->convert = check_attr_export_subst(check);
 167         }
 168
 169         if (args->verbose)
 170                 fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 171
 172         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 173                 err = write_entry(args, oid, path.buf, path.len, mode, NULL, 0);
 174                 if (err)
 175                         return err;
 176                 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
 177         }
 178
 179         /* Stream it? */
 180         if (S_ISREG(mode) && !args->convert &&
 181             oid_object_info(args->repo, oid, &size) == OBJ_BLOB &&
 182             size > big_file_threshold)
 183                 return write_entry(args, oid, path.buf, path.len, mode, NULL, size);
 184
 185         buffer = object_file_to_archive(args, path.buf, oid, mode, &type, &size);
 186         if (!buffer)
 187                 return error(_("cannot read '%s'"), oid_to_hex(oid));
 188         err = write_entry(args, oid, path.buf, path.len, mode, buffer, size);
 189         free(buffer);
 190         return err;
 191 }
 192
 193 static void queue_directory(const struct object_id *oid,
 194                 struct strbuf *base, const char *filename,
 195                 unsigned mode, struct archiver_context *c)
 196 {
 197         struct directory *d;
 198         size_t len = st_add4(base->len, 1, strlen(filename), 1);
 199         d = xmalloc(st_add(sizeof(*d), len));
 200         d->up      = c->bottom;
 201         d->baselen = base->len;
 202         d->mode    = mode;
 203         c->bottom  = d;
 204         d->len = xsnprintf(d->path, len, "%.*s%s/", (int)base->len, base->buf, filename);
 205         oidcpy(&d->oid, oid);
 206 }
 207
 208 static int write_directory(struct archiver_context *c)
 209 {
 210         struct directory *d = c->bottom;
 211         int ret;
 212
 213         if (!d)
 214                 return 0;
 215         c->bottom = d->up;
 216         d->path[d->len - 1] = '\0'; /* no trailing slash */
 217         ret =
 218                 write_directory(c) ||
 219                 write_archive_entry(&d->oid, d->path, d->baselen,
 220                                     d->path + d->baselen, d->mode,
 221                                     c) != READ_TREE_RECURSIVE;
 222         free(d);
 223         return ret ? -1 : 0;
 224 }
 225
 226 static int queue_or_write_archive_entry(const struct object_id *oid,
 227                 struct strbuf *base, const char *filename,
 228                 unsigned mode, void *context)
 229 {
 230         struct archiver_context *c = context;
 231
 232         while (c->bottom &&
 233                !(base->len >= c->bottom->len &&
 234                  !strncmp(base->buf, c->bottom->path, c->bottom->len))) {
 235                 struct directory *next = c->bottom->up;
 236                 free(c->bottom);
 237                 c->bottom = next;
 238         }
 239
 240         if (S_ISDIR(mode)) {
 241                 size_t baselen = base->len;
 242                 const struct attr_check *check;
 243
 244                 /* Borrow base, but restore its original value when done. */
 245                 strbuf_addstr(base, filename);
 246                 strbuf_addch(base, '/');
 247                 check = get_archive_attrs(c->args->repo->index, base->buf);
 248                 strbuf_setlen(base, baselen);
 249
 250                 if (check_attr_export_ignore(check))
 251                         return 0;
 252                 queue_directory(oid, base, filename, mode, c);
 253                 return READ_TREE_RECURSIVE;
 254         }
 255
 256         if (write_directory(c))
 257                 return -1;
 258         return write_archive_entry(oid, base->buf, base->len, filename, mode,
 259                                    context);
 260 }
 261
 262 struct extra_file_info {
 263         char *base;
 264         struct stat stat;
 265         void *content;
 266 };
 267
 268 int write_archive_entries(struct archiver_args *args,
 269                 write_archive_entry_fn_t write_entry)
 270 {
 271         struct archiver_context context;
 272         struct unpack_trees_options opts;
 273         struct tree_desc t;
 274         int err;
 275         struct strbuf path_in_archive = STRBUF_INIT;
 276         struct strbuf content = STRBUF_INIT;
 277         struct object_id fake_oid;
 278         int i;
 279
 280         oidcpy(&fake_oid, null_oid());
 281
 282         if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
 283                 size_t len = args->baselen;
 284
 285                 while (len > 1 && args->base[len - 2] == '/')
 286                         len--;
 287                 if (args->verbose)
 288                         fprintf(stderr, "%.*s\n", (int)len, args->base);
 289                 err = write_entry(args, &args->tree->object.oid, args->base,
 290                                   len, 040777, NULL, 0);
 291                 if (err)
 292                         return err;
 293         }
 294
 295         memset(&context, 0, sizeof(context));
 296         context.args = args;
 297         context.write_entry = write_entry;
 298
 299         /*
 300          * Setup index and instruct attr to read index only
 301          */
 302         if (!args->worktree_attributes) {
 303                 memset(&opts, 0, sizeof(opts));
 304                 opts.index_only = 1;
 305                 opts.head_idx = -1;
 306                 opts.src_index = args->repo->index;
 307                 opts.dst_index = args->repo->index;
 308                 opts.fn = oneway_merge;
 309                 init_tree_desc(&t, args->tree->buffer, args->tree->size);
 310                 if (unpack_trees(1, &t, &opts))
 311                         return -1;
 312                 git_attr_set_direction(GIT_ATTR_INDEX);
 313         }
 314
 315         err = read_tree(args->repo, args->tree,
 316                         &args->pathspec,
 317                         queue_or_write_archive_entry,
 318                         &context);
 319         if (err == READ_TREE_RECURSIVE)
 320                 err = 0;
 321         while (context.bottom) {
 322                 struct directory *next = context.bottom->up;
 323                 free(context.bottom);
 324                 context.bottom = next;
 325         }
 326
 327         for (i = 0; i < args->extra_files.nr; i++) {
 328                 struct string_list_item *item = args->extra_files.items + i;
 329                 char *path = item->string;
 330                 struct extra_file_info *info = item->util;
 331
 332                 put_be64(fake_oid.hash, i + 1);
 333
 334                 if (!info->content) {
 335                         strbuf_reset(&path_in_archive);
 336                         if (info->base)
 337                                 strbuf_addstr(&path_in_archive, info->base);
 338                         strbuf_addstr(&path_in_archive, basename(path));
 339
 340                         strbuf_reset(&content);
 341                         if (strbuf_read_file(&content, path, info->stat.st_size) < 0)
 342                                 err = error_errno(_("cannot read '%s'"), path);
 343                         else
 344                                 err = write_entry(args, &fake_oid, path_in_archive.buf,
 345                                                   path_in_archive.len,
 346                                                   canon_mode(info->stat.st_mode),
 347                                                   content.buf, content.len);
 348                 } else {
 349                         err = write_entry(args, &fake_oid,
 350                                           path, strlen(path),
 351                                           canon_mode(info->stat.st_mode),
 352                                           info->content, info->stat.st_size);
 353                 }
 354
 355                 if (err)
 356                         break;
 357         }
 358         strbuf_release(&path_in_archive);
 359         strbuf_release(&content);
 360
 361         return err;
 362 }
 363
 364 static const struct archiver *lookup_archiver(const char *name)
 365 {
 366         int i;
 367
 368         if (!name)
 369                 return NULL;
 370
 371         for (i = 0; i < nr_archivers; i++) {
 372                 if (!strcmp(name, archivers[i]->name))
 373                         return archivers[i];
 374         }
 375         return NULL;
 376 }
 377
 378 struct path_exists_context {
 379         struct pathspec pathspec;
 380         struct archiver_args *args;
 381 };
 382
 383 static int reject_entry(const struct object_id *oid UNUSED,
 384                         struct strbuf *base,
 385                         const char *filename, unsigned mode,
 386                         void *context)
 387 {
 388         int ret = -1;
 389         struct path_exists_context *ctx = context;
 390
 391         if (S_ISDIR(mode)) {
 392                 struct strbuf sb = STRBUF_INIT;
 393                 strbuf_addbuf(&sb, base);
 394                 strbuf_addstr(&sb, filename);
 395                 if (!match_pathspec(ctx->args->repo->index,
 396                                     &ctx->pathspec,
 397                                     sb.buf, sb.len, 0, NULL, 1))
 398                         ret = READ_TREE_RECURSIVE;
 399                 strbuf_release(&sb);
 400         }
 401         return ret;
 402 }
 403
 404 static int path_exists(struct archiver_args *args, const char *path)
 405 {
 406         const char *paths[] = { path, NULL };
 407         struct path_exists_context ctx;
 408         int ret;
 409
 410         ctx.args = args;
 411         parse_pathspec(&ctx.pathspec, 0, 0, "", paths);
 412         ctx.pathspec.recursive = 1;
 413         ret = read_tree(args->repo, args->tree,
 414                         &ctx.pathspec,
 415                         reject_entry, &ctx);
 416         clear_pathspec(&ctx.pathspec);
 417         return ret != 0;
 418 }
 419
 420 static void parse_pathspec_arg(const char **pathspec,
 421                 struct archiver_args *ar_args)
 422 {
 423         /*
 424          * must be consistent with parse_pathspec in path_exists()
 425          * Also if pathspec patterns are dependent, we're in big
 426          * trouble as we test each one separately
 427          */
 428         parse_pathspec(&ar_args->pathspec, 0,
 429                        PATHSPEC_PREFER_FULL,
 430                        "", pathspec);
 431         ar_args->pathspec.recursive = 1;
 432         if (pathspec) {
 433                 while (*pathspec) {
 434                         if (**pathspec && !path_exists(ar_args, *pathspec))
 435                                 die(_("pathspec '%s' did not match any files"), *pathspec);
 436                         pathspec++;
 437                 }
 438         }
 439 }
 440
 441 static void parse_treeish_arg(const char **argv,
 442                 struct archiver_args *ar_args, const char *prefix,
 443                 int remote)
 444 {
 445         const char *name = argv[0];
 446         const struct object_id *commit_oid;
 447         time_t archive_time;
 448         struct tree *tree;
 449         const struct commit *commit;
 450         struct object_id oid;
 451         char *ref = NULL;
 452
 453         /* Remotes are only allowed to fetch actual refs */
 454         if (remote && !remote_allow_unreachable) {
 455                 const char *colon = strchrnul(name, ':');
 456                 int refnamelen = colon - name;
 457
 458                 if (!dwim_ref(name, refnamelen, &oid, &ref, 0))
 459                         die(_("no such ref: %.*s"), refnamelen, name);
 460         } else {
 461                 dwim_ref(name, strlen(name), &oid, &ref, 0);
 462         }
 463
 464         if (get_oid(name, &oid))
 465                 die(_("not a valid object name: %s"), name);
 466
 467         commit = lookup_commit_reference_gently(ar_args->repo, &oid, 1);
 468         if (commit) {
 469                 commit_oid = &commit->object.oid;
 470                 archive_time = commit->date;
 471         } else {
 472                 commit_oid = NULL;
 473                 archive_time = time(NULL);
 474         }
 475
 476         tree = parse_tree_indirect(&oid);
 477         if (!tree)
 478                 die(_("not a tree object: %s"), oid_to_hex(&oid));
 479
 480         if (prefix) {
 481                 struct object_id tree_oid;
 482                 unsigned short mode;
 483                 int err;
 484
 485                 err = get_tree_entry(ar_args->repo,
 486                                      &tree->object.oid,
 487                                      prefix, &tree_oid,
 488                                      &mode);
 489                 if (err || !S_ISDIR(mode))
 490                         die(_("current working directory is untracked"));
 491
 492                 tree = parse_tree_indirect(&tree_oid);
 493         }
 494         ar_args->refname = ref;
 495         ar_args->tree = tree;
 496         ar_args->commit_oid = commit_oid;
 497         ar_args->commit = commit;
 498         ar_args->time = archive_time;
 499 }
 500
 501 static void extra_file_info_clear(void *util, const char *str UNUSED)
 502 {
 503         struct extra_file_info *info = util;
 504         free(info->base);
 505         free(info->content);
 506         free(info);
 507 }
 508
 509 static int add_file_cb(const struct option *opt, const char *arg, int unset)
 510 {
 511         struct archiver_args *args = opt->value;
 512         const char **basep = (const char **)opt->defval;
 513         const char *base = *basep;
 514         char *path;
 515         struct string_list_item *item;
 516         struct extra_file_info *info;
 517
 518         if (unset) {
 519                 string_list_clear_func(&args->extra_files,
 520                                        extra_file_info_clear);
 521                 return 0;
 522         }
 523
 524         if (!arg)
 525                 return -1;
 526
 527         info = xmalloc(sizeof(*info));
 528         info->base = xstrdup_or_null(base);
 529
 530         if (!strcmp(opt->long_name, "add-file")) {
 531                 path = prefix_filename(args->prefix, arg);
 532                 if (stat(path, &info->stat))
 533                         die(_("File not found: %s"), path);
 534                 if (!S_ISREG(info->stat.st_mode))
 535                         die(_("Not a regular file: %s"), path);
 536                 info->content = NULL; /* read the file later */
 537         } else if (!strcmp(opt->long_name, "add-virtual-file")) {
 538                 struct strbuf buf = STRBUF_INIT;
 539                 const char *p = arg;
 540
 541                 if (*p != '"')
 542                         p = strchr(p, ':');
 543                 else if (unquote_c_style(&buf, p, &p) < 0)
 544                         die(_("unclosed quote: '%s'"), arg);
 545
 546                 if (!p || *p != ':')
 547                         die(_("missing colon: '%s'"), arg);
 548
 549                 if (p == arg)
 550                         die(_("empty file name: '%s'"), arg);
 551
 552                 path = buf.len ?
 553                         strbuf_detach(&buf, NULL) : xstrndup(arg, p - arg);
 554
 555                 if (args->prefix) {
 556                         char *save = path;
 557                         path = prefix_filename(args->prefix, path);
 558                         free(save);
 559                 }
 560                 memset(&info->stat, 0, sizeof(info->stat));
 561                 info->stat.st_mode = S_IFREG | 0644;
 562                 info->content = xstrdup(p + 1);
 563                 info->stat.st_size = strlen(info->content);
 564         } else {
 565                 BUG("add_file_cb() called for %s", opt->long_name);
 566         }
 567         item = string_list_append_nodup(&args->extra_files, path);
 568         item->util = info;
 569
 570         return 0;
 571 }
 572
 573 static int number_callback(const struct option *opt, const char *arg, int unset)
 574 {
 575         BUG_ON_OPT_NEG(unset);
 576         *(int *)opt->value = strtol(arg, NULL, 10);
 577         return 0;
 578 }
 579
 580 static int parse_archive_args(int argc, const char **argv,
 581                 const struct archiver **ar, struct archiver_args *args,
 582                 const char *name_hint, int is_remote)
 583 {
 584         const char *format = NULL;
 585         const char *base = NULL;
 586         const char *remote = NULL;
 587         const char *exec = NULL;
 588         const char *output = NULL;
 589         int compression_level = -1;
 590         int verbose = 0;
 591         int i;
 592         int list = 0;
 593         int worktree_attributes = 0;
 594         struct option opts[] = {
 595                 OPT_GROUP(""),
 596                 OPT_STRING(0, "format", &format, N_("fmt"), N_("archive format")),
 597                 OPT_STRING(0, "prefix", &base, N_("prefix"),
 598                         N_("prepend prefix to each pathname in the archive")),
 599                 { OPTION_CALLBACK, 0, "add-file", args, N_("file"),
 600                   N_("add untracked file to archive"), 0, add_file_cb,
 601                   (intptr_t)&base },
 602                 { OPTION_CALLBACK, 0, "add-virtual-file", args,
 603                   N_("path:content"), N_("add untracked file to archive"), 0,
 604                   add_file_cb, (intptr_t)&base },
 605                 OPT_STRING('o', "output", &output, N_("file"),
 606                         N_("write the archive to this file")),
 607                 OPT_BOOL(0, "worktree-attributes", &worktree_attributes,
 608                         N_("read .gitattributes in working directory")),
 609                 OPT__VERBOSE(&verbose, N_("report archived files on stderr")),
 610                 OPT_NUMBER_CALLBACK(&compression_level,
 611                         N_("set compression level"), number_callback),
 612                 OPT_GROUP(""),
 613                 OPT_BOOL('l', "list", &list,
 614                         N_("list supported archive formats")),
 615                 OPT_GROUP(""),
 616                 OPT_STRING(0, "remote", &remote, N_("repo"),
 617                         N_("retrieve the archive from remote repository <repo>")),
 618                 OPT_STRING(0, "exec", &exec, N_("command"),
 619                         N_("path to the remote git-upload-archive command")),
 620                 OPT_END()
 621         };
 622
 623         argc = parse_options(argc, argv, NULL, opts, archive_usage, 0);
 624
 625         if (remote)
 626                 die(_("Unexpected option --remote"));
 627         if (exec)
 628                 die(_("the option '%s' requires '%s'"), "--exec", "--remote");
 629         if (output)
 630                 die(_("Unexpected option --output"));
 631         if (is_remote && args->extra_files.nr)
 632                 die(_("options '%s' and '%s' cannot be used together"), "--add-file", "--remote");
 633
 634         if (!base)
 635                 base = "";
 636
 637         if (list) {
 638                 for (i = 0; i < nr_archivers; i++)
 639                         if (!is_remote || archivers[i]->flags & ARCHIVER_REMOTE)
 640                                 printf("%s\n", archivers[i]->name);
 641                 exit(0);
 642         }
 643
 644         if (!format && name_hint)
 645                 format = archive_format_from_filename(name_hint);
 646         if (!format)
 647                 format = "tar";
 648
 649         /* We need at least one parameter -- tree-ish */
 650         if (argc < 1)
 651                 usage_with_options(archive_usage, opts);
 652         *ar = lookup_archiver(format);
 653         if (!*ar || (is_remote && !((*ar)->flags & ARCHIVER_REMOTE)))
 654                 die(_("Unknown archive format '%s'"), format);
 655
 656         args->compression_level = Z_DEFAULT_COMPRESSION;
 657         if (compression_level != -1) {
 658                 int levels_ok = (*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS;
 659                 int high_ok = (*ar)->flags & ARCHIVER_HIGH_COMPRESSION_LEVELS;
 660                 if (levels_ok && (compression_level <= 9 || high_ok))
 661                         args->compression_level = compression_level;
 662                 else {
 663                         die(_("Argument not supported for format '%s': -%d"),
 664                                         format, compression_level);
 665                 }
 666         }
 667         args->verbose = verbose;
 668         args->base = base;
 669         args->baselen = strlen(base);
 670         args->worktree_attributes = worktree_attributes;
 671
 672         return argc;
 673 }
 674
 675 int write_archive(int argc, const char **argv, const char *prefix,
 676                   struct repository *repo,
 677                   const char *name_hint, int remote)
 678 {
 679         const struct archiver *ar = NULL;
 680         struct pretty_print_describe_status describe_status = {0};
 681         struct pretty_print_context ctx = {0};
 682         struct archiver_args args;
 683         int rc;
 684
 685         git_config_get_bool("uploadarchive.allowunreachable", &remote_allow_unreachable);
 686         git_config(git_default_config, NULL);
 687
 688         describe_status.max_invocations = 1;
 689         ctx.date_mode.type = DATE_NORMAL;
 690         ctx.abbrev = DEFAULT_ABBREV;
 691         ctx.describe_status = &describe_status;
 692         args.pretty_ctx = &ctx;
 693         args.repo = repo;
 694         args.prefix = prefix;
 695         string_list_init_dup(&args.extra_files);
 696         argc = parse_archive_args(argc, argv, &ar, &args, name_hint, remote);
 697         if (!startup_info->have_repository) {
 698                 /*
 699                  * We know this will die() with an error, so we could just
 700                  * die ourselves; but its error message will be more specific
 701                  * than what we could write here.
 702                  */
 703                 setup_git_directory();
 704         }
 705
 706         parse_treeish_arg(argv, &args, prefix, remote);
 707         parse_pathspec_arg(argv + 1, &args);
 708
 709         rc = ar->write_archive(ar, &args);
 710
 711         string_list_clear_func(&args.extra_files, extra_file_info_clear);
 712         free(args.refname);
 713
 714         return rc;
 715 }
 716
 717 static int match_extension(const char *filename, const char *ext)
 718 {
 719         int prefixlen = strlen(filename) - strlen(ext);
 720
 721         /*
 722          * We need 1 character for the '.', and 1 character to ensure that the
 723          * prefix is non-empty (k.e., we don't match .tar.gz with no actual
 724          * filename).
 725          */
 726         if (prefixlen < 2 || filename[prefixlen - 1] != '.')
 727                 return 0;
 728         return !strcmp(filename + prefixlen, ext);
 729 }
 730
 731 const char *archive_format_from_filename(const char *filename)
 732 {
 733         int i;
 734
 735         for (i = 0; i < nr_archivers; i++)
 736                 if (match_extension(filename, archivers[i]->name))
 737                         return archivers[i]->name;
 738         return NULL;
 739 }