builtin/repack.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "config.h"
   4 #include "dir.h"
   5 #include "parse-options.h"
   6 #include "run-command.h"
   7 #include "sigchain.h"
   8 #include "strbuf.h"
   9 #include "string-list.h"
  10 #include "strvec.h"
  11 #include "midx.h"
  12 #include "packfile.h"
  13 #include "prune-packed.h"
  14 #include "object-store.h"
  15 #include "promisor-remote.h"
  16 #include "shallow.h"
  17
  18 static int delta_base_offset = 1;
  19 static int pack_kept_objects = -1;
  20 static int write_bitmaps = -1;
  21 static int use_delta_islands;
  22 static char *packdir, *packtmp;
  23
  24 static const char *const git_repack_usage[] = {
  25         N_("git repack [<options>]"),
  26         NULL
  27 };
  28
  29 static const char incremental_bitmap_conflict_error[] = N_(
  30 "Incremental repacks are incompatible with bitmap indexes.  Use\n"
  31 "--no-write-bitmap-index or disable the pack.writebitmaps configuration."
  32 );
  33
  34
  35 static int repack_config(const char *var, const char *value, void *cb)
  36 {
  37         if (!strcmp(var, "repack.usedeltabaseoffset")) {
  38                 delta_base_offset = git_config_bool(var, value);
  39                 return 0;
  40         }
  41         if (!strcmp(var, "repack.packkeptobjects")) {
  42                 pack_kept_objects = git_config_bool(var, value);
  43                 return 0;
  44         }
  45         if (!strcmp(var, "repack.writebitmaps") ||
  46             !strcmp(var, "pack.writebitmaps")) {
  47                 write_bitmaps = git_config_bool(var, value);
  48                 return 0;
  49         }
  50         if (!strcmp(var, "repack.usedeltaislands")) {
  51                 use_delta_islands = git_config_bool(var, value);
  52                 return 0;
  53         }
  54         return git_default_config(var, value, cb);
  55 }
  56
  57 /*
  58  * Remove temporary $GIT_OBJECT_DIRECTORY/pack/.tmp-$$-pack-* files.
  59  */
  60 static void remove_temporary_files(void)
  61 {
  62         struct strbuf buf = STRBUF_INIT;
  63         size_t dirlen, prefixlen;
  64         DIR *dir;
  65         struct dirent *e;
  66
  67         dir = opendir(packdir);
  68         if (!dir)
  69                 return;
  70
  71         /* Point at the slash at the end of ".../objects/pack/" */
  72         dirlen = strlen(packdir) + 1;
  73         strbuf_addstr(&buf, packtmp);
  74         /* Hold the length of  ".tmp-%d-pack-" */
  75         prefixlen = buf.len - dirlen;
  76
  77         while ((e = readdir(dir))) {
  78                 if (strncmp(e->d_name, buf.buf + dirlen, prefixlen))
  79                         continue;
  80                 strbuf_setlen(&buf, dirlen);
  81                 strbuf_addstr(&buf, e->d_name);
  82                 unlink(buf.buf);
  83         }
  84         closedir(dir);
  85         strbuf_release(&buf);
  86 }
  87
  88 static void remove_pack_on_signal(int signo)
  89 {
  90         remove_temporary_files();
  91         sigchain_pop(signo);
  92         raise(signo);
  93 }
  94
  95 /*
  96  * Adds all packs hex strings to the fname list, which do not
  97  * have a corresponding .keep file. These packs are not to
  98  * be kept if we are going to pack everything into one file.
  99  */
 100 static void get_non_kept_pack_filenames(struct string_list *fname_list,
 101                                         const struct string_list *extra_keep)
 102 {
 103         DIR *dir;
 104         struct dirent *e;
 105         char *fname;
 106
 107         if (!(dir = opendir(packdir)))
 108                 return;
 109
 110         while ((e = readdir(dir)) != NULL) {
 111                 size_t len;
 112                 int i;
 113
 114                 for (i = 0; i < extra_keep->nr; i++)
 115                         if (!fspathcmp(e->d_name, extra_keep->items[i].string))
 116                                 break;
 117                 if (extra_keep->nr > 0 && i < extra_keep->nr)
 118                         continue;
 119
 120                 if (!strip_suffix(e->d_name, ".pack", &len))
 121                         continue;
 122
 123                 fname = xmemdupz(e->d_name, len);
 124
 125                 if (!file_exists(mkpath("%s/%s.keep", packdir, fname)))
 126                         string_list_append_nodup(fname_list, fname);
 127                 else
 128                         free(fname);
 129         }
 130         closedir(dir);
 131 }
 132
 133 static void remove_redundant_pack(const char *dir_name, const char *base_name)
 134 {
 135         struct strbuf buf = STRBUF_INIT;
 136         struct multi_pack_index *m = get_local_multi_pack_index(the_repository);
 137         strbuf_addf(&buf, "%s.pack", base_name);
 138         if (m && midx_contains_pack(m, buf.buf))
 139                 clear_midx_file(the_repository);
 140         strbuf_insertf(&buf, 0, "%s/", dir_name);
 141         unlink_pack_path(buf.buf, 1);
 142         strbuf_release(&buf);
 143 }
 144
 145 struct pack_objects_args {
 146         const char *window;
 147         const char *window_memory;
 148         const char *depth;
 149         const char *threads;
 150         const char *max_pack_size;
 151         int no_reuse_delta;
 152         int no_reuse_object;
 153         int quiet;
 154         int local;
 155 };
 156
 157 static void prepare_pack_objects(struct child_process *cmd,
 158                                  const struct pack_objects_args *args)
 159 {
 160         strvec_push(&cmd->args, "pack-objects");
 161         if (args->window)
 162                 strvec_pushf(&cmd->args, "--window=%s", args->window);
 163         if (args->window_memory)
 164                 strvec_pushf(&cmd->args, "--window-memory=%s", args->window_memory);
 165         if (args->depth)
 166                 strvec_pushf(&cmd->args, "--depth=%s", args->depth);
 167         if (args->threads)
 168                 strvec_pushf(&cmd->args, "--threads=%s", args->threads);
 169         if (args->max_pack_size)
 170                 strvec_pushf(&cmd->args, "--max-pack-size=%s", args->max_pack_size);
 171         if (args->no_reuse_delta)
 172                 strvec_pushf(&cmd->args, "--no-reuse-delta");
 173         if (args->no_reuse_object)
 174                 strvec_pushf(&cmd->args, "--no-reuse-object");
 175         if (args->local)
 176                 strvec_push(&cmd->args,  "--local");
 177         if (args->quiet)
 178                 strvec_push(&cmd->args,  "--quiet");
 179         if (delta_base_offset)
 180                 strvec_push(&cmd->args,  "--delta-base-offset");
 181         strvec_push(&cmd->args, packtmp);
 182         cmd->git_cmd = 1;
 183         cmd->out = -1;
 184 }
 185
 186 /*
 187  * Write oid to the given struct child_process's stdin, starting it first if
 188  * necessary.
 189  */
 190 static int write_oid(const struct object_id *oid, struct packed_git *pack,
 191                      uint32_t pos, void *data)
 192 {
 193         struct child_process *cmd = data;
 194
 195         if (cmd->in == -1) {
 196                 if (start_command(cmd))
 197                         die(_("could not start pack-objects to repack promisor objects"));
 198         }
 199
 200         xwrite(cmd->in, oid_to_hex(oid), the_hash_algo->hexsz);
 201         xwrite(cmd->in, "\n", 1);
 202         return 0;
 203 }
 204
 205 static void repack_promisor_objects(const struct pack_objects_args *args,
 206                                     struct string_list *names)
 207 {
 208         struct child_process cmd = CHILD_PROCESS_INIT;
 209         FILE *out;
 210         struct strbuf line = STRBUF_INIT;
 211
 212         prepare_pack_objects(&cmd, args);
 213         cmd.in = -1;
 214
 215         /*
 216          * NEEDSWORK: Giving pack-objects only the OIDs without any ordering
 217          * hints may result in suboptimal deltas in the resulting pack. See if
 218          * the OIDs can be sent with fake paths such that pack-objects can use a
 219          * {type -> existing pack order} ordering when computing deltas instead
 220          * of a {type -> size} ordering, which may produce better deltas.
 221          */
 222         for_each_packed_object(write_oid, &cmd,
 223                                FOR_EACH_OBJECT_PROMISOR_ONLY);
 224
 225         if (cmd.in == -1)
 226                 /* No packed objects; cmd was never started */
 227                 return;
 228
 229         close(cmd.in);
 230
 231         out = xfdopen(cmd.out, "r");
 232         while (strbuf_getline_lf(&line, out) != EOF) {
 233                 char *promisor_name;
 234                 int fd;
 235                 if (line.len != the_hash_algo->hexsz)
 236                         die(_("repack: Expecting full hex object ID lines only from pack-objects."));
 237                 string_list_append(names, line.buf);
 238
 239                 /*
 240                  * pack-objects creates the .pack and .idx files, but not the
 241                  * .promisor file. Create the .promisor file, which is empty.
 242                  *
 243                  * NEEDSWORK: fetch-pack sometimes generates non-empty
 244                  * .promisor files containing the ref names and associated
 245                  * hashes at the point of generation of the corresponding
 246                  * packfile, but this would not preserve their contents. Maybe
 247                  * concatenate the contents of all .promisor files instead of
 248                  * just creating a new empty file.
 249                  */
 250                 promisor_name = mkpathdup("%s-%s.promisor", packtmp,
 251                                           line.buf);
 252                 fd = open(promisor_name, O_CREAT|O_EXCL|O_WRONLY, 0600);
 253                 if (fd < 0)
 254                         die_errno(_("unable to create '%s'"), promisor_name);
 255                 close(fd);
 256                 free(promisor_name);
 257         }
 258         fclose(out);
 259         if (finish_command(&cmd))
 260                 die(_("could not finish pack-objects to repack promisor objects"));
 261 }
 262
 263 #define ALL_INTO_ONE 1
 264 #define LOOSEN_UNREACHABLE 2
 265
 266 int cmd_repack(int argc, const char **argv, const char *prefix)
 267 {
 268         struct {
 269                 const char *name;
 270                 unsigned optional:1;
 271         } exts[] = {
 272                 {".pack"},
 273                 {".idx"},
 274                 {".bitmap", 1},
 275                 {".promisor", 1},
 276         };
 277         struct child_process cmd = CHILD_PROCESS_INIT;
 278         struct string_list_item *item;
 279         struct string_list names = STRING_LIST_INIT_DUP;
 280         struct string_list rollback = STRING_LIST_INIT_NODUP;
 281         struct string_list existing_packs = STRING_LIST_INIT_DUP;
 282         struct strbuf line = STRBUF_INIT;
 283         int i, ext, ret, failed;
 284         FILE *out;
 285
 286         /* variables to be filled by option parsing */
 287         int pack_everything = 0;
 288         int delete_redundant = 0;
 289         const char *unpack_unreachable = NULL;
 290         int keep_unreachable = 0;
 291         struct string_list keep_pack_list = STRING_LIST_INIT_NODUP;
 292         int no_update_server_info = 0;
 293         struct pack_objects_args po_args = {NULL};
 294
 295         struct option builtin_repack_options[] = {
 296                 OPT_BIT('a', NULL, &pack_everything,
 297                                 N_("pack everything in a single pack"), ALL_INTO_ONE),
 298                 OPT_BIT('A', NULL, &pack_everything,
 299                                 N_("same as -a, and turn unreachable objects loose"),
 300                                    LOOSEN_UNREACHABLE | ALL_INTO_ONE),
 301                 OPT_BOOL('d', NULL, &delete_redundant,
 302                                 N_("remove redundant packs, and run git-prune-packed")),
 303                 OPT_BOOL('f', NULL, &po_args.no_reuse_delta,
 304                                 N_("pass --no-reuse-delta to git-pack-objects")),
 305                 OPT_BOOL('F', NULL, &po_args.no_reuse_object,
 306                                 N_("pass --no-reuse-object to git-pack-objects")),
 307                 OPT_BOOL('n', NULL, &no_update_server_info,
 308                                 N_("do not run git-update-server-info")),
 309                 OPT__QUIET(&po_args.quiet, N_("be quiet")),
 310                 OPT_BOOL('l', "local", &po_args.local,
 311                                 N_("pass --local to git-pack-objects")),
 312                 OPT_BOOL('b', "write-bitmap-index", &write_bitmaps,
 313                                 N_("write bitmap index")),
 314                 OPT_BOOL('i', "delta-islands", &use_delta_islands,
 315                                 N_("pass --delta-islands to git-pack-objects")),
 316                 OPT_STRING(0, "unpack-unreachable", &unpack_unreachable, N_("approxidate"),
 317                                 N_("with -A, do not loosen objects older than this")),
 318                 OPT_BOOL('k', "keep-unreachable", &keep_unreachable,
 319                                 N_("with -a, repack unreachable objects")),
 320                 OPT_STRING(0, "window", &po_args.window, N_("n"),
 321                                 N_("size of the window used for delta compression")),
 322                 OPT_STRING(0, "window-memory", &po_args.window_memory, N_("bytes"),
 323                                 N_("same as the above, but limit memory size instead of entries count")),
 324                 OPT_STRING(0, "depth", &po_args.depth, N_("n"),
 325                                 N_("limits the maximum delta depth")),
 326                 OPT_STRING(0, "threads", &po_args.threads, N_("n"),
 327                                 N_("limits the maximum number of threads")),
 328                 OPT_STRING(0, "max-pack-size", &po_args.max_pack_size, N_("bytes"),
 329                                 N_("maximum size of each packfile")),
 330                 OPT_BOOL(0, "pack-kept-objects", &pack_kept_objects,
 331                                 N_("repack objects in packs marked with .keep")),
 332                 OPT_STRING_LIST(0, "keep-pack", &keep_pack_list, N_("name"),
 333                                 N_("do not repack this pack")),
 334                 OPT_END()
 335         };
 336
 337         git_config(repack_config, NULL);
 338
 339         argc = parse_options(argc, argv, prefix, builtin_repack_options,
 340                                 git_repack_usage, 0);
 341
 342         if (delete_redundant && repository_format_precious_objects)
 343                 die(_("cannot delete packs in a precious-objects repo"));
 344
 345         if (keep_unreachable &&
 346             (unpack_unreachable || (pack_everything & LOOSEN_UNREACHABLE)))
 347                 die(_("--keep-unreachable and -A are incompatible"));
 348
 349         if (write_bitmaps < 0) {
 350                 if (!(pack_everything & ALL_INTO_ONE) ||
 351                     !is_bare_repository())
 352                         write_bitmaps = 0;
 353         }
 354         if (pack_kept_objects < 0)
 355                 pack_kept_objects = write_bitmaps > 0;
 356
 357         if (write_bitmaps && !(pack_everything & ALL_INTO_ONE))
 358                 die(_(incremental_bitmap_conflict_error));
 359
 360         packdir = mkpathdup("%s/pack", get_object_directory());
 361         packtmp = mkpathdup("%s/.tmp-%d-pack", packdir, (int)getpid());
 362
 363         sigchain_push_common(remove_pack_on_signal);
 364
 365         prepare_pack_objects(&cmd, &po_args);
 366
 367         strvec_push(&cmd.args, "--keep-true-parents");
 368         if (!pack_kept_objects)
 369                 strvec_push(&cmd.args, "--honor-pack-keep");
 370         for (i = 0; i < keep_pack_list.nr; i++)
 371                 strvec_pushf(&cmd.args, "--keep-pack=%s",
 372                              keep_pack_list.items[i].string);
 373         strvec_push(&cmd.args, "--non-empty");
 374         strvec_push(&cmd.args, "--all");
 375         strvec_push(&cmd.args, "--reflog");
 376         strvec_push(&cmd.args, "--indexed-objects");
 377         if (has_promisor_remote())
 378                 strvec_push(&cmd.args, "--exclude-promisor-objects");
 379         if (write_bitmaps > 0)
 380                 strvec_push(&cmd.args, "--write-bitmap-index");
 381         else if (write_bitmaps < 0)
 382                 strvec_push(&cmd.args, "--write-bitmap-index-quiet");
 383         if (use_delta_islands)
 384                 strvec_push(&cmd.args, "--delta-islands");
 385
 386         if (pack_everything & ALL_INTO_ONE) {
 387                 get_non_kept_pack_filenames(&existing_packs, &keep_pack_list);
 388
 389                 repack_promisor_objects(&po_args, &names);
 390
 391                 if (existing_packs.nr && delete_redundant) {
 392                         if (unpack_unreachable) {
 393                                 strvec_pushf(&cmd.args,
 394                                              "--unpack-unreachable=%s",
 395                                              unpack_unreachable);
 396                                 strvec_push(&cmd.env_array, "GIT_REF_PARANOIA=1");
 397                         } else if (pack_everything & LOOSEN_UNREACHABLE) {
 398                                 strvec_push(&cmd.args,
 399                                             "--unpack-unreachable");
 400                         } else if (keep_unreachable) {
 401                                 strvec_push(&cmd.args, "--keep-unreachable");
 402                                 strvec_push(&cmd.args, "--pack-loose-unreachable");
 403                         } else {
 404                                 strvec_push(&cmd.env_array, "GIT_REF_PARANOIA=1");
 405                         }
 406                 }
 407         } else {
 408                 strvec_push(&cmd.args, "--unpacked");
 409                 strvec_push(&cmd.args, "--incremental");
 410         }
 411
 412         cmd.no_stdin = 1;
 413
 414         ret = start_command(&cmd);
 415         if (ret)
 416                 return ret;
 417
 418         out = xfdopen(cmd.out, "r");
 419         while (strbuf_getline_lf(&line, out) != EOF) {
 420                 if (line.len != the_hash_algo->hexsz)
 421                         die(_("repack: Expecting full hex object ID lines only from pack-objects."));
 422                 string_list_append(&names, line.buf);
 423         }
 424         fclose(out);
 425         ret = finish_command(&cmd);
 426         if (ret)
 427                 return ret;
 428
 429         if (!names.nr && !po_args.quiet)
 430                 printf_ln(_("Nothing new to pack."));
 431
 432         close_object_store(the_repository->objects);
 433
 434         /*
 435          * Ok we have prepared all new packfiles.
 436          * First see if there are packs of the same name and if so
 437          * if we can move them out of the way (this can happen if we
 438          * repacked immediately after packing fully.
 439          */
 440         failed = 0;
 441         for_each_string_list_item(item, &names) {
 442                 for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 443                         char *fname, *fname_old;
 444
 445                         fname = mkpathdup("%s/pack-%s%s", packdir,
 446                                                 item->string, exts[ext].name);
 447                         if (!file_exists(fname)) {
 448                                 free(fname);
 449                                 continue;
 450                         }
 451
 452                         fname_old = mkpathdup("%s/old-%s%s", packdir,
 453                                                 item->string, exts[ext].name);
 454                         if (file_exists(fname_old))
 455                                 if (unlink(fname_old))
 456                                         failed = 1;
 457
 458                         if (!failed && rename(fname, fname_old)) {
 459                                 free(fname);
 460                                 free(fname_old);
 461                                 failed = 1;
 462                                 break;
 463                         } else {
 464                                 string_list_append(&rollback, fname);
 465                                 free(fname_old);
 466                         }
 467                 }
 468                 if (failed)
 469                         break;
 470         }
 471         if (failed) {
 472                 struct string_list rollback_failure = STRING_LIST_INIT_DUP;
 473                 for_each_string_list_item(item, &rollback) {
 474                         char *fname, *fname_old;
 475                         fname = mkpathdup("%s/%s", packdir, item->string);
 476                         fname_old = mkpathdup("%s/old-%s", packdir, item->string);
 477                         if (rename(fname_old, fname))
 478                                 string_list_append(&rollback_failure, fname);
 479                         free(fname);
 480                         free(fname_old);
 481                 }
 482
 483                 if (rollback_failure.nr) {
 484                         int i;
 485                         fprintf(stderr,
 486                                 _("WARNING: Some packs in use have been renamed by\n"
 487                                   "WARNING: prefixing old- to their name, in order to\n"
 488                                   "WARNING: replace them with the new version of the\n"
 489                                   "WARNING: file.  But the operation failed, and the\n"
 490                                   "WARNING: attempt to rename them back to their\n"
 491                                   "WARNING: original names also failed.\n"
 492                                   "WARNING: Please rename them in %s manually:\n"), packdir);
 493                         for (i = 0; i < rollback_failure.nr; i++)
 494                                 fprintf(stderr, "WARNING:   old-%s -> %s\n",
 495                                         rollback_failure.items[i].string,
 496                                         rollback_failure.items[i].string);
 497                 }
 498                 exit(1);
 499         }
 500
 501         /* Now the ones with the same name are out of the way... */
 502         for_each_string_list_item(item, &names) {
 503                 for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 504                         char *fname, *fname_old;
 505                         struct stat statbuffer;
 506                         int exists = 0;
 507                         fname = mkpathdup("%s/pack-%s%s",
 508                                         packdir, item->string, exts[ext].name);
 509                         fname_old = mkpathdup("%s-%s%s",
 510                                         packtmp, item->string, exts[ext].name);
 511                         if (!stat(fname_old, &statbuffer)) {
 512                                 statbuffer.st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
 513                                 chmod(fname_old, statbuffer.st_mode);
 514                                 exists = 1;
 515                         }
 516                         if (exists || !exts[ext].optional) {
 517                                 if (rename(fname_old, fname))
 518                                         die_errno(_("renaming '%s' failed"), fname_old);
 519                         }
 520                         free(fname);
 521                         free(fname_old);
 522                 }
 523         }
 524
 525         /* Remove the "old-" files */
 526         for_each_string_list_item(item, &names) {
 527                 for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 528                         char *fname;
 529                         fname = mkpathdup("%s/old-%s%s",
 530                                           packdir,
 531                                           item->string,
 532                                           exts[ext].name);
 533                         if (remove_path(fname))
 534                                 warning(_("failed to remove '%s'"), fname);
 535                         free(fname);
 536                 }
 537         }
 538
 539         /* End of pack replacement. */
 540
 541         reprepare_packed_git(the_repository);
 542
 543         if (delete_redundant) {
 544                 const int hexsz = the_hash_algo->hexsz;
 545                 int opts = 0;
 546                 string_list_sort(&names);
 547                 for_each_string_list_item(item, &existing_packs) {
 548                         char *sha1;
 549                         size_t len = strlen(item->string);
 550                         if (len < hexsz)
 551                                 continue;
 552                         sha1 = item->string + len - hexsz;
 553                         if (!string_list_has_string(&names, sha1))
 554                                 remove_redundant_pack(packdir, item->string);
 555                 }
 556                 if (!po_args.quiet && isatty(2))
 557                         opts |= PRUNE_PACKED_VERBOSE;
 558                 prune_packed_objects(opts);
 559
 560                 if (!keep_unreachable &&
 561                     (!(pack_everything & LOOSEN_UNREACHABLE) ||
 562                      unpack_unreachable) &&
 563                     is_repository_shallow(the_repository))
 564                         prune_shallow(PRUNE_QUICK);
 565         }
 566
 567         if (!no_update_server_info)
 568                 update_server_info(0);
 569         remove_temporary_files();
 570
 571         if (git_env_bool(GIT_TEST_MULTI_PACK_INDEX, 0))
 572                 write_midx_file(get_object_directory(), 0);
 573
 574         string_list_clear(&names, 0);
 575         string_list_clear(&rollback, 0);
 576         string_list_clear(&existing_packs, 0);
 577         strbuf_release(&line);
 578
 579         return 0;
 580 }