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 "argv-array.h"
  11 #include "packfile.h"
  12 #include "object-store.h"
  13
  14 static int delta_base_offset = 1;
  15 static int pack_kept_objects = -1;
  16 static int write_bitmaps;
  17 static char *packdir, *packtmp;
  18
  19 static const char *const git_repack_usage[] = {
  20         N_("git repack [<options>]"),
  21         NULL
  22 };
  23
  24 static const char incremental_bitmap_conflict_error[] = N_(
  25 "Incremental repacks are incompatible with bitmap indexes.  Use\n"
  26 "--no-write-bitmap-index or disable the pack.writebitmaps configuration."
  27 );
  28
  29
  30 static int repack_config(const char *var, const char *value, void *cb)
  31 {
  32         if (!strcmp(var, "repack.usedeltabaseoffset")) {
  33                 delta_base_offset = git_config_bool(var, value);
  34                 return 0;
  35         }
  36         if (!strcmp(var, "repack.packkeptobjects")) {
  37                 pack_kept_objects = git_config_bool(var, value);
  38                 return 0;
  39         }
  40         if (!strcmp(var, "repack.writebitmaps") ||
  41             !strcmp(var, "pack.writebitmaps")) {
  42                 write_bitmaps = git_config_bool(var, value);
  43                 return 0;
  44         }
  45         return git_default_config(var, value, cb);
  46 }
  47
  48 /*
  49  * Remove temporary $GIT_OBJECT_DIRECTORY/pack/.tmp-$$-pack-* files.
  50  */
  51 static void remove_temporary_files(void)
  52 {
  53         struct strbuf buf = STRBUF_INIT;
  54         size_t dirlen, prefixlen;
  55         DIR *dir;
  56         struct dirent *e;
  57
  58         dir = opendir(packdir);
  59         if (!dir)
  60                 return;
  61
  62         /* Point at the slash at the end of ".../objects/pack/" */
  63         dirlen = strlen(packdir) + 1;
  64         strbuf_addstr(&buf, packtmp);
  65         /* Hold the length of  ".tmp-%d-pack-" */
  66         prefixlen = buf.len - dirlen;
  67
  68         while ((e = readdir(dir))) {
  69                 if (strncmp(e->d_name, buf.buf + dirlen, prefixlen))
  70                         continue;
  71                 strbuf_setlen(&buf, dirlen);
  72                 strbuf_addstr(&buf, e->d_name);
  73                 unlink(buf.buf);
  74         }
  75         closedir(dir);
  76         strbuf_release(&buf);
  77 }
  78
  79 static void remove_pack_on_signal(int signo)
  80 {
  81         remove_temporary_files();
  82         sigchain_pop(signo);
  83         raise(signo);
  84 }
  85
  86 /*
  87  * Adds all packs hex strings to the fname list, which do not
  88  * have a corresponding .keep file. These packs are not to
  89  * be kept if we are going to pack everything into one file.
  90  */
  91 static void get_non_kept_pack_filenames(struct string_list *fname_list,
  92                                         const struct string_list *extra_keep)
  93 {
  94         DIR *dir;
  95         struct dirent *e;
  96         char *fname;
  97
  98         if (!(dir = opendir(packdir)))
  99                 return;
 100
 101         while ((e = readdir(dir)) != NULL) {
 102                 size_t len;
 103                 int i;
 104
 105                 for (i = 0; i < extra_keep->nr; i++)
 106                         if (!fspathcmp(e->d_name, extra_keep->items[i].string))
 107                                 break;
 108                 if (extra_keep->nr > 0 && i < extra_keep->nr)
 109                         continue;
 110
 111                 if (!strip_suffix(e->d_name, ".pack", &len))
 112                         continue;
 113
 114                 fname = xmemdupz(e->d_name, len);
 115
 116                 if (!file_exists(mkpath("%s/%s.keep", packdir, fname)))
 117                         string_list_append_nodup(fname_list, fname);
 118                 else
 119                         free(fname);
 120         }
 121         closedir(dir);
 122 }
 123
 124 static void remove_redundant_pack(const char *dir_name, const char *base_name)
 125 {
 126         const char *exts[] = {".pack", ".idx", ".keep", ".bitmap", ".promisor"};
 127         int i;
 128         struct strbuf buf = STRBUF_INIT;
 129         size_t plen;
 130
 131         strbuf_addf(&buf, "%s/%s", dir_name, base_name);
 132         plen = buf.len;
 133
 134         for (i = 0; i < ARRAY_SIZE(exts); i++) {
 135                 strbuf_setlen(&buf, plen);
 136                 strbuf_addstr(&buf, exts[i]);
 137                 unlink(buf.buf);
 138         }
 139         strbuf_release(&buf);
 140 }
 141
 142 struct pack_objects_args {
 143         const char *window;
 144         const char *window_memory;
 145         const char *depth;
 146         const char *threads;
 147         const char *max_pack_size;
 148         int no_reuse_delta;
 149         int no_reuse_object;
 150         int quiet;
 151         int local;
 152 };
 153
 154 static void prepare_pack_objects(struct child_process *cmd,
 155                                  const struct pack_objects_args *args)
 156 {
 157         argv_array_push(&cmd->args, "pack-objects");
 158         if (args->window)
 159                 argv_array_pushf(&cmd->args, "--window=%s", args->window);
 160         if (args->window_memory)
 161                 argv_array_pushf(&cmd->args, "--window-memory=%s", args->window_memory);
 162         if (args->depth)
 163                 argv_array_pushf(&cmd->args, "--depth=%s", args->depth);
 164         if (args->threads)
 165                 argv_array_pushf(&cmd->args, "--threads=%s", args->threads);
 166         if (args->max_pack_size)
 167                 argv_array_pushf(&cmd->args, "--max-pack-size=%s", args->max_pack_size);
 168         if (args->no_reuse_delta)
 169                 argv_array_pushf(&cmd->args, "--no-reuse-delta");
 170         if (args->no_reuse_object)
 171                 argv_array_pushf(&cmd->args, "--no-reuse-object");
 172         if (args->local)
 173                 argv_array_push(&cmd->args,  "--local");
 174         if (args->quiet)
 175                 argv_array_push(&cmd->args,  "--quiet");
 176         if (delta_base_offset)
 177                 argv_array_push(&cmd->args,  "--delta-base-offset");
 178         argv_array_push(&cmd->args, packtmp);
 179         cmd->git_cmd = 1;
 180         cmd->out = -1;
 181 }
 182
 183 /*
 184  * Write oid to the given struct child_process's stdin, starting it first if
 185  * necessary.
 186  */
 187 static int write_oid(const struct object_id *oid, struct packed_git *pack,
 188                      uint32_t pos, void *data)
 189 {
 190         struct child_process *cmd = data;
 191
 192         if (cmd->in == -1) {
 193                 if (start_command(cmd))
 194                         die("Could not start pack-objects to repack promisor objects");
 195         }
 196
 197         xwrite(cmd->in, oid_to_hex(oid), GIT_SHA1_HEXSZ);
 198         xwrite(cmd->in, "\n", 1);
 199         return 0;
 200 }
 201
 202 static void repack_promisor_objects(const struct pack_objects_args *args,
 203                                     struct string_list *names)
 204 {
 205         struct child_process cmd = CHILD_PROCESS_INIT;
 206         FILE *out;
 207         struct strbuf line = STRBUF_INIT;
 208
 209         prepare_pack_objects(&cmd, args);
 210         cmd.in = -1;
 211
 212         /*
 213          * NEEDSWORK: Giving pack-objects only the OIDs without any ordering
 214          * hints may result in suboptimal deltas in the resulting pack. See if
 215          * the OIDs can be sent with fake paths such that pack-objects can use a
 216          * {type -> existing pack order} ordering when computing deltas instead
 217          * of a {type -> size} ordering, which may produce better deltas.
 218          */
 219         for_each_packed_object(write_oid, &cmd,
 220                                FOR_EACH_OBJECT_PROMISOR_ONLY);
 221
 222         if (cmd.in == -1)
 223                 /* No packed objects; cmd was never started */
 224                 return;
 225
 226         close(cmd.in);
 227
 228         out = xfdopen(cmd.out, "r");
 229         while (strbuf_getline_lf(&line, out) != EOF) {
 230                 char *promisor_name;
 231                 int fd;
 232                 if (line.len != 40)
 233                         die("repack: Expecting 40 character sha1 lines only from pack-objects.");
 234                 string_list_append(names, line.buf);
 235
 236                 /*
 237                  * pack-objects creates the .pack and .idx files, but not the
 238                  * .promisor file. Create the .promisor file, which is empty.
 239                  */
 240                 promisor_name = mkpathdup("%s-%s.promisor", packtmp,
 241                                           line.buf);
 242                 fd = open(promisor_name, O_CREAT|O_EXCL|O_WRONLY, 0600);
 243                 if (fd < 0)
 244                         die_errno("unable to create '%s'", promisor_name);
 245                 close(fd);
 246                 free(promisor_name);
 247         }
 248         fclose(out);
 249         if (finish_command(&cmd))
 250                 die("Could not finish pack-objects to repack promisor objects");
 251 }
 252
 253 #define ALL_INTO_ONE 1
 254 #define LOOSEN_UNREACHABLE 2
 255
 256 int cmd_repack(int argc, const char **argv, const char *prefix)
 257 {
 258         struct {
 259                 const char *name;
 260                 unsigned optional:1;
 261         } exts[] = {
 262                 {".pack"},
 263                 {".idx"},
 264                 {".bitmap", 1},
 265                 {".promisor", 1},
 266         };
 267         struct child_process cmd = CHILD_PROCESS_INIT;
 268         struct string_list_item *item;
 269         struct string_list names = STRING_LIST_INIT_DUP;
 270         struct string_list rollback = STRING_LIST_INIT_NODUP;
 271         struct string_list existing_packs = STRING_LIST_INIT_DUP;
 272         struct strbuf line = STRBUF_INIT;
 273         int i, ext, ret, failed;
 274         FILE *out;
 275
 276         /* variables to be filled by option parsing */
 277         int pack_everything = 0;
 278         int delete_redundant = 0;
 279         const char *unpack_unreachable = NULL;
 280         int keep_unreachable = 0;
 281         struct string_list keep_pack_list = STRING_LIST_INIT_NODUP;
 282         int no_update_server_info = 0;
 283         struct pack_objects_args po_args = {NULL};
 284
 285         struct option builtin_repack_options[] = {
 286                 OPT_BIT('a', NULL, &pack_everything,
 287                                 N_("pack everything in a single pack"), ALL_INTO_ONE),
 288                 OPT_BIT('A', NULL, &pack_everything,
 289                                 N_("same as -a, and turn unreachable objects loose"),
 290                                    LOOSEN_UNREACHABLE | ALL_INTO_ONE),
 291                 OPT_BOOL('d', NULL, &delete_redundant,
 292                                 N_("remove redundant packs, and run git-prune-packed")),
 293                 OPT_BOOL('f', NULL, &po_args.no_reuse_delta,
 294                                 N_("pass --no-reuse-delta to git-pack-objects")),
 295                 OPT_BOOL('F', NULL, &po_args.no_reuse_object,
 296                                 N_("pass --no-reuse-object to git-pack-objects")),
 297                 OPT_BOOL('n', NULL, &no_update_server_info,
 298                                 N_("do not run git-update-server-info")),
 299                 OPT__QUIET(&po_args.quiet, N_("be quiet")),
 300                 OPT_BOOL('l', "local", &po_args.local,
 301                                 N_("pass --local to git-pack-objects")),
 302                 OPT_BOOL('b', "write-bitmap-index", &write_bitmaps,
 303                                 N_("write bitmap index")),
 304                 OPT_STRING(0, "unpack-unreachable", &unpack_unreachable, N_("approxidate"),
 305                                 N_("with -A, do not loosen objects older than this")),
 306                 OPT_BOOL('k', "keep-unreachable", &keep_unreachable,
 307                                 N_("with -a, repack unreachable objects")),
 308                 OPT_STRING(0, "window", &po_args.window, N_("n"),
 309                                 N_("size of the window used for delta compression")),
 310                 OPT_STRING(0, "window-memory", &po_args.window_memory, N_("bytes"),
 311                                 N_("same as the above, but limit memory size instead of entries count")),
 312                 OPT_STRING(0, "depth", &po_args.depth, N_("n"),
 313                                 N_("limits the maximum delta depth")),
 314                 OPT_STRING(0, "threads", &po_args.threads, N_("n"),
 315                                 N_("limits the maximum number of threads")),
 316                 OPT_STRING(0, "max-pack-size", &po_args.max_pack_size, N_("bytes"),
 317                                 N_("maximum size of each packfile")),
 318                 OPT_BOOL(0, "pack-kept-objects", &pack_kept_objects,
 319                                 N_("repack objects in packs marked with .keep")),
 320                 OPT_STRING_LIST(0, "keep-pack", &keep_pack_list, N_("name"),
 321                                 N_("do not repack this pack")),
 322                 OPT_END()
 323         };
 324
 325         git_config(repack_config, NULL);
 326
 327         argc = parse_options(argc, argv, prefix, builtin_repack_options,
 328                                 git_repack_usage, 0);
 329
 330         if (delete_redundant && repository_format_precious_objects)
 331                 die(_("cannot delete packs in a precious-objects repo"));
 332
 333         if (keep_unreachable &&
 334             (unpack_unreachable || (pack_everything & LOOSEN_UNREACHABLE)))
 335                 die(_("--keep-unreachable and -A are incompatible"));
 336
 337         if (pack_kept_objects < 0)
 338                 pack_kept_objects = write_bitmaps;
 339
 340         if (write_bitmaps && !(pack_everything & ALL_INTO_ONE))
 341                 die(_(incremental_bitmap_conflict_error));
 342
 343         packdir = mkpathdup("%s/pack", get_object_directory());
 344         packtmp = mkpathdup("%s/.tmp-%d-pack", packdir, (int)getpid());
 345
 346         sigchain_push_common(remove_pack_on_signal);
 347
 348         prepare_pack_objects(&cmd, &po_args);
 349
 350         argv_array_push(&cmd.args, "--keep-true-parents");
 351         if (!pack_kept_objects)
 352                 argv_array_push(&cmd.args, "--honor-pack-keep");
 353         for (i = 0; i < keep_pack_list.nr; i++)
 354                 argv_array_pushf(&cmd.args, "--keep-pack=%s",
 355                                  keep_pack_list.items[i].string);
 356         argv_array_push(&cmd.args, "--non-empty");
 357         argv_array_push(&cmd.args, "--all");
 358         argv_array_push(&cmd.args, "--reflog");
 359         argv_array_push(&cmd.args, "--indexed-objects");
 360         if (repository_format_partial_clone)
 361                 argv_array_push(&cmd.args, "--exclude-promisor-objects");
 362         if (write_bitmaps)
 363                 argv_array_push(&cmd.args, "--write-bitmap-index");
 364
 365         if (pack_everything & ALL_INTO_ONE) {
 366                 get_non_kept_pack_filenames(&existing_packs, &keep_pack_list);
 367
 368                 repack_promisor_objects(&po_args, &names);
 369
 370                 if (existing_packs.nr && delete_redundant) {
 371                         if (unpack_unreachable) {
 372                                 argv_array_pushf(&cmd.args,
 373                                                 "--unpack-unreachable=%s",
 374                                                 unpack_unreachable);
 375                                 argv_array_push(&cmd.env_array, "GIT_REF_PARANOIA=1");
 376                         } else if (pack_everything & LOOSEN_UNREACHABLE) {
 377                                 argv_array_push(&cmd.args,
 378                                                 "--unpack-unreachable");
 379                         } else if (keep_unreachable) {
 380                                 argv_array_push(&cmd.args, "--keep-unreachable");
 381                                 argv_array_push(&cmd.args, "--pack-loose-unreachable");
 382                         } else {
 383                                 argv_array_push(&cmd.env_array, "GIT_REF_PARANOIA=1");
 384                         }
 385                 }
 386         } else {
 387                 argv_array_push(&cmd.args, "--unpacked");
 388                 argv_array_push(&cmd.args, "--incremental");
 389         }
 390
 391         cmd.no_stdin = 1;
 392
 393         ret = start_command(&cmd);
 394         if (ret)
 395                 return ret;
 396
 397         out = xfdopen(cmd.out, "r");
 398         while (strbuf_getline_lf(&line, out) != EOF) {
 399                 if (line.len != 40)
 400                         die("repack: Expecting 40 character sha1 lines only from pack-objects.");
 401                 string_list_append(&names, line.buf);
 402         }
 403         fclose(out);
 404         ret = finish_command(&cmd);
 405         if (ret)
 406                 return ret;
 407
 408         if (!names.nr && !po_args.quiet)
 409                 printf("Nothing new to pack.\n");
 410
 411         /*
 412          * Ok we have prepared all new packfiles.
 413          * First see if there are packs of the same name and if so
 414          * if we can move them out of the way (this can happen if we
 415          * repacked immediately after packing fully.
 416          */
 417         failed = 0;
 418         for_each_string_list_item(item, &names) {
 419                 for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 420                         char *fname, *fname_old;
 421                         fname = mkpathdup("%s/pack-%s%s", packdir,
 422                                                 item->string, exts[ext].name);
 423                         if (!file_exists(fname)) {
 424                                 free(fname);
 425                                 continue;
 426                         }
 427
 428                         fname_old = mkpathdup("%s/old-%s%s", packdir,
 429                                                 item->string, exts[ext].name);
 430                         if (file_exists(fname_old))
 431                                 if (unlink(fname_old))
 432                                         failed = 1;
 433
 434                         if (!failed && rename(fname, fname_old)) {
 435                                 free(fname);
 436                                 free(fname_old);
 437                                 failed = 1;
 438                                 break;
 439                         } else {
 440                                 string_list_append(&rollback, fname);
 441                                 free(fname_old);
 442                         }
 443                 }
 444                 if (failed)
 445                         break;
 446         }
 447         if (failed) {
 448                 struct string_list rollback_failure = STRING_LIST_INIT_DUP;
 449                 for_each_string_list_item(item, &rollback) {
 450                         char *fname, *fname_old;
 451                         fname = mkpathdup("%s/%s", packdir, item->string);
 452                         fname_old = mkpathdup("%s/old-%s", packdir, item->string);
 453                         if (rename(fname_old, fname))
 454                                 string_list_append(&rollback_failure, fname);
 455                         free(fname);
 456                         free(fname_old);
 457                 }
 458
 459                 if (rollback_failure.nr) {
 460                         int i;
 461                         fprintf(stderr,
 462                                 "WARNING: Some packs in use have been renamed by\n"
 463                                 "WARNING: prefixing old- to their name, in order to\n"
 464                                 "WARNING: replace them with the new version of the\n"
 465                                 "WARNING: file.  But the operation failed, and the\n"
 466                                 "WARNING: attempt to rename them back to their\n"
 467                                 "WARNING: original names also failed.\n"
 468                                 "WARNING: Please rename them in %s manually:\n", packdir);
 469                         for (i = 0; i < rollback_failure.nr; i++)
 470                                 fprintf(stderr, "WARNING:   old-%s -> %s\n",
 471                                         rollback_failure.items[i].string,
 472                                         rollback_failure.items[i].string);
 473                 }
 474                 exit(1);
 475         }
 476
 477         /* Now the ones with the same name are out of the way... */
 478         for_each_string_list_item(item, &names) {
 479                 for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 480                         char *fname, *fname_old;
 481                         struct stat statbuffer;
 482                         int exists = 0;
 483                         fname = mkpathdup("%s/pack-%s%s",
 484                                         packdir, item->string, exts[ext].name);
 485                         fname_old = mkpathdup("%s-%s%s",
 486                                         packtmp, item->string, exts[ext].name);
 487                         if (!stat(fname_old, &statbuffer)) {
 488                                 statbuffer.st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
 489                                 chmod(fname_old, statbuffer.st_mode);
 490                                 exists = 1;
 491                         }
 492                         if (exists || !exts[ext].optional) {
 493                                 if (rename(fname_old, fname))
 494                                         die_errno(_("renaming '%s' failed"), fname_old);
 495                         }
 496                         free(fname);
 497                         free(fname_old);
 498                 }
 499         }
 500
 501         /* Remove the "old-" files */
 502         for_each_string_list_item(item, &names) {
 503                 for (ext = 0; ext < ARRAY_SIZE(exts); ext++) {
 504                         char *fname;
 505                         fname = mkpathdup("%s/old-%s%s",
 506                                           packdir,
 507                                           item->string,
 508                                           exts[ext].name);
 509                         if (remove_path(fname))
 510                                 warning(_("failed to remove '%s'"), fname);
 511                         free(fname);
 512                 }
 513         }
 514
 515         /* End of pack replacement. */
 516
 517         reprepare_packed_git(the_repository);
 518
 519         if (delete_redundant) {
 520                 int opts = 0;
 521                 string_list_sort(&names);
 522                 for_each_string_list_item(item, &existing_packs) {
 523                         char *sha1;
 524                         size_t len = strlen(item->string);
 525                         if (len < 40)
 526                                 continue;
 527                         sha1 = item->string + len - 40;
 528                         if (!string_list_has_string(&names, sha1))
 529                                 remove_redundant_pack(packdir, item->string);
 530                 }
 531                 if (!po_args.quiet && isatty(2))
 532                         opts |= PRUNE_PACKED_VERBOSE;
 533                 prune_packed_objects(opts);
 534         }
 535
 536         if (!no_update_server_info)
 537                 update_server_info(0);
 538         remove_temporary_files();
 539         string_list_clear(&names, 0);
 540         string_list_clear(&rollback, 0);
 541         string_list_clear(&existing_packs, 0);
 542         strbuf_release(&line);
 543
 544         return 0;
 545 }