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