granicus.if.org Git - postgresql/blob - src/bin/pg_resetxlog/pg_resetxlog.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * pg_resetxlog.c
   4  *        A utility to "zero out" the xlog when it's corrupt beyond recovery.
   5  *        Can also rebuild pg_control if needed.
   6  *
   7  * The theory of operation is fairly simple:
   8  *        1. Read the existing pg_control (which will include the last
   9  *               checkpoint record).  If it is an old format then update to
  10  *               current format.
  11  *        2. If pg_control is corrupt, attempt to intuit reasonable values,
  12  *               by scanning the old xlog if necessary.
  13  *        3. Modify pg_control to reflect a "shutdown" state with a checkpoint
  14  *               record at the start of xlog.
  15  *        4. Flush the existing xlog files and write a new segment with
  16  *               just a checkpoint record in it.  The new segment is positioned
  17  *               just past the end of the old xlog, so that existing LSNs in
  18  *               data pages will appear to be "in the past".
  19  * This is all pretty straightforward except for the intuition part of
  20  * step 2 ...
  21  *
  22  *
  23  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  24  * Portions Copyright (c) 1994, Regents of the University of California
  25  *
  26  * $PostgreSQL: pgsql/src/bin/pg_resetxlog/pg_resetxlog.c,v 1.19 2004/05/25 01:00:25 momjian Exp $
  27  *
  28  *-------------------------------------------------------------------------
  29  */
  30 #include "postgres.h"
  31
  32 #include <errno.h>
  33 #include <unistd.h>
  34 #include <time.h>
  35 #include <sys/stat.h>
  36 #include <sys/time.h>
  37 #include <fcntl.h>
  38 #include <dirent.h>
  39 #include <locale.h>
  40
  41 #include "access/xlog.h"
  42 #include "catalog/catversion.h"
  43 #include "catalog/pg_control.h"
  44
  45 extern int      optind;
  46 extern char *optarg;
  47
  48 #define _(x) gettext((x))
  49
  50
  51 /******************** stuff copied from xlog.c ********************/
  52
  53 /* Increment an xlogid/segment pair */
  54 #define NextLogSeg(logId, logSeg)       \
  55         do { \
  56                 if ((logSeg) >= XLogSegsPerFile-1) \
  57                 { \
  58                         (logId)++; \
  59                         (logSeg) = 0; \
  60                 } \
  61                 else \
  62                         (logSeg)++; \
  63         } while (0)
  64
  65 #define XLogFileName(path, log, seg)    \
  66                         snprintf(path, MAXPGPATH, "%s/%08X%08X",        \
  67                                          XLogDir, log, seg)
  68
  69 /******************** end of stuff copied from xlog.c ********************/
  70
  71 static char XLogDir[MAXPGPATH];
  72 static char ControlFilePath[MAXPGPATH];
  73
  74 static ControlFileData ControlFile;             /* pg_control values */
  75 static uint32 newXlogId,
  76                         newXlogSeg;                     /* ID/Segment of new XLOG segment */
  77 static bool guessed = false;    /* T if we had to guess at any values */
  78 static const char *progname;
  79
  80 static bool ReadControlFile(void);
  81 static void GuessControlValues(void);
  82 static void PrintControlValues(bool guessed);
  83 static void RewriteControlFile(void);
  84 static void KillExistingXLOG(void);
  85 static void WriteEmptyXLOG(void);
  86 static void usage(void);
  87
  88
  89 int
  90 main(int argc, char *argv[])
  91 {
  92         int                     c;
  93         bool            force = false;
  94         bool            noupdate = false;
  95         TransactionId set_xid = 0;
  96         Oid                     set_oid = 0;
  97         uint32          minXlogId = 0,
  98                                 minXlogSeg = 0;
  99         char       *endptr;
 100         char       *endptr2;
 101         char       *DataDir;
 102         int                     fd;
 103         char            path[MAXPGPATH];
 104
 105         set_pglocale(argv[0], "pg_resetxlog");
 106
 107         progname = get_progname(argv[0]);
 108
 109         if (argc > 1)
 110         {
 111                 if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
 112                 {
 113                         usage();
 114                         exit(0);
 115                 }
 116                 if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
 117                 {
 118                         puts("pg_resetxlog (PostgreSQL) " PG_VERSION);
 119                         exit(0);
 120                 }
 121         }
 122
 123
 124         while ((c = getopt(argc, argv, "fl:no:x:")) != -1)
 125         {
 126                 switch (c)
 127                 {
 128                         case 'f':
 129                                 force = true;
 130                                 break;
 131
 132                         case 'n':
 133                                 noupdate = true;
 134                                 break;
 135
 136                         case 'x':
 137                                 set_xid = strtoul(optarg, &endptr, 0);
 138                                 if (endptr == optarg || *endptr != '\0')
 139                                 {
 140                                         fprintf(stderr, _("%s: invalid argument for option -x\n"), progname);
 141                                         fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 142                                         exit(1);
 143                                 }
 144                                 if (set_xid == 0)
 145                                 {
 146                                         fprintf(stderr, _("%s: transaction ID (-x) must not be 0\n"), progname);
 147                                         exit(1);
 148                                 }
 149                                 break;
 150
 151                         case 'o':
 152                                 set_oid = strtoul(optarg, &endptr, 0);
 153                                 if (endptr == optarg || *endptr != '\0')
 154                                 {
 155                                         fprintf(stderr, _("%s: invalid argument for option -o\n"), progname);
 156                                         fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 157                                         exit(1);
 158                                 }
 159                                 if (set_oid == 0)
 160                                 {
 161                                         fprintf(stderr, _("%s: OID (-o) must not be 0\n"), progname);
 162                                         exit(1);
 163                                 }
 164                                 break;
 165
 166                         case 'l':
 167                                 minXlogId = strtoul(optarg, &endptr, 0);
 168                                 if (endptr == optarg || *endptr != ',')
 169                                 {
 170                                         fprintf(stderr, _("%s: invalid argument for option -l\n"), progname);
 171                                         fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 172                                         exit(1);
 173                                 }
 174                                 minXlogSeg = strtoul(endptr + 1, &endptr2, 0);
 175                                 if (endptr2 == endptr + 1 || *endptr2 != '\0')
 176                                 {
 177                                         fprintf(stderr, _("%s: invalid argument for option -l\n"), progname);
 178                                         fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 179                                         exit(1);
 180                                 }
 181                                 break;
 182
 183                         default:
 184                                 fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 185                                 exit(1);
 186                 }
 187         }
 188
 189         if (optind == argc)
 190         {
 191                 fprintf(stderr, _("%s: no data directory specified\n"), progname);
 192                 fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 193                 exit(1);
 194         }
 195
 196         DataDir = argv[optind];
 197         snprintf(XLogDir, MAXPGPATH, "%s/pg_xlog", DataDir);
 198         snprintf(ControlFilePath, MAXPGPATH, "%s/global/pg_control", DataDir);
 199
 200         /*
 201          * Check for a postmaster lock file --- if there is one, refuse to
 202          * proceed, on grounds we might be interfering with a live
 203          * installation.
 204          */
 205         snprintf(path, MAXPGPATH, "%s/postmaster.pid", DataDir);
 206
 207         if ((fd = open(path, O_RDONLY)) < 0)
 208         {
 209                 if (errno != ENOENT)
 210                 {
 211                         fprintf(stderr, _("%s: could not open file \"%s\" for reading: %s\n"), progname, path, strerror(errno));
 212                         exit(1);
 213                 }
 214         }
 215         else
 216         {
 217                 fprintf(stderr, _("%s: lock file \"%s\" exists\n"
 218                                                   "Is a server running?  If not, delete the lock file and try again.\n"),
 219                                 progname, path);
 220                 exit(1);
 221         }
 222
 223         /*
 224          * Attempt to read the existing pg_control file
 225          */
 226         if (!ReadControlFile())
 227                 GuessControlValues();
 228
 229         /*
 230          * Adjust fields if required by switches.  (Do this now so that
 231          * printout, if any, includes these values.)
 232          */
 233         if (set_xid != 0)
 234                 ControlFile.checkPointCopy.nextXid = set_xid;
 235
 236         if (set_oid != 0)
 237                 ControlFile.checkPointCopy.nextOid = set_oid;
 238
 239         if (minXlogId > ControlFile.logId ||
 240                 (minXlogId == ControlFile.logId &&
 241                  minXlogSeg > ControlFile.logSeg))
 242         {
 243                 ControlFile.logId = minXlogId;
 244                 ControlFile.logSeg = minXlogSeg;
 245         }
 246
 247         /*
 248          * If we had to guess anything, and -f was not given, just print the
 249          * guessed values and exit.  Also print if -n is given.
 250          */
 251         if ((guessed && !force) || noupdate)
 252         {
 253                 PrintControlValues(guessed);
 254                 if (!noupdate)
 255                 {
 256                         printf(_("\nIf these values seem acceptable, use -f to force reset.\n"));
 257                         exit(1);
 258                 }
 259                 else
 260                         exit(0);
 261         }
 262
 263         /*
 264          * Don't reset from a dirty pg_control without -f, either.
 265          */
 266         if (ControlFile.state != DB_SHUTDOWNED && !force)
 267         {
 268                 printf(_("The database server was not shut down cleanly.\n"
 269                          "Resetting the transaction log may cause data to be lost.\n"
 270                          "If you want to proceed anyway, use -f to force reset.\n"));
 271                 exit(1);
 272         }
 273
 274         /*
 275          * Else, do the dirty deed.
 276          */
 277         RewriteControlFile();
 278         KillExistingXLOG();
 279         WriteEmptyXLOG();
 280
 281         printf(_("Transaction log reset\n"));
 282         return 0;
 283 }
 284
 285
 286 /*
 287  * Try to read the existing pg_control file.
 288  *
 289  * This routine is also responsible for updating old pg_control versions
 290  * to the current format.  (Currently we don't do anything of the sort.)
 291  */
 292 static bool
 293 ReadControlFile(void)
 294 {
 295         int                     fd;
 296         int                     len;
 297         char       *buffer;
 298         crc64           crc;
 299
 300         if ((fd = open(ControlFilePath, O_RDONLY)) < 0)
 301         {
 302                 /*
 303                  * If pg_control is not there at all, or we can't read it, the
 304                  * odds are we've been handed a bad DataDir path, so give up. User
 305                  * can do "touch pg_control" to force us to proceed.
 306                  */
 307                 fprintf(stderr, _("%s: could not open file \"%s\" for reading: %s\n"),
 308                                 progname, ControlFilePath, strerror(errno));
 309                 if (errno == ENOENT)
 310                         fprintf(stderr, _("If you are sure the data directory path is correct, execute\n"
 311                                                           "  touch %s\n"
 312                                                           "and try again.\n"),
 313                                         ControlFilePath);
 314                 exit(1);
 315         }
 316
 317         /* Use malloc to ensure we have a maxaligned buffer */
 318         buffer = (char *) malloc(BLCKSZ);
 319
 320         len = read(fd, buffer, BLCKSZ);
 321         if (len < 0)
 322         {
 323                 fprintf(stderr, _("%s: could not read file \"%s\": %s\n"),
 324                                 progname, ControlFilePath, strerror(errno));
 325                 exit(1);
 326         }
 327         close(fd);
 328
 329         if (len >= sizeof(ControlFileData) &&
 330                 ((ControlFileData *) buffer)->pg_control_version == PG_CONTROL_VERSION)
 331         {
 332                 /* Check the CRC. */
 333                 INIT_CRC64(crc);
 334                 COMP_CRC64(crc,
 335                                    buffer + sizeof(crc64),
 336                                    sizeof(ControlFileData) - sizeof(crc64));
 337                 FIN_CRC64(crc);
 338
 339                 if (EQ_CRC64(crc, ((ControlFileData *) buffer)->crc))
 340                 {
 341                         /* Valid data... */
 342                         memcpy(&ControlFile, buffer, sizeof(ControlFile));
 343                         return true;
 344                 }
 345
 346                 fprintf(stderr, _("%s: pg_control exists but has invalid CRC; proceed with caution\n"),
 347                                 progname);
 348                 /* We will use the data anyway, but treat it as guessed. */
 349                 memcpy(&ControlFile, buffer, sizeof(ControlFile));
 350                 guessed = true;
 351                 return true;
 352         }
 353
 354         /* Looks like it's a mess. */
 355         fprintf(stderr, _("%s: pg_control exists but is broken or unknown version; ignoring it\n"),
 356                         progname);
 357         return false;
 358 }
 359
 360
 361 /*
 362  * Guess at pg_control values when we can't read the old ones.
 363  */
 364 static void
 365 GuessControlValues(void)
 366 {
 367         uint64          sysidentifier;
 368         struct timeval tv;
 369         char       *localeptr;
 370
 371         /*
 372          * Set up a completely default set of pg_control values.
 373          */
 374         guessed = true;
 375         memset(&ControlFile, 0, sizeof(ControlFile));
 376
 377         ControlFile.pg_control_version = PG_CONTROL_VERSION;
 378         ControlFile.catalog_version_no = CATALOG_VERSION_NO;
 379
 380         /*
 381          * Create a new unique installation identifier, since we can no longer
 382          * use any old XLOG records.  See notes in xlog.c about the algorithm.
 383          */
 384         gettimeofday(&tv, NULL);
 385         sysidentifier = ((uint64) tv.tv_sec) << 32;
 386         sysidentifier |= (uint32) (tv.tv_sec | tv.tv_usec);
 387
 388         ControlFile.system_identifier = sysidentifier;
 389
 390         ControlFile.checkPointCopy.redo.xlogid = 0;
 391         ControlFile.checkPointCopy.redo.xrecoff = SizeOfXLogPHD + SizeOfXLogRecord + SizeOfXLogFHD;
 392         ControlFile.checkPointCopy.undo = ControlFile.checkPointCopy.redo;
 393         ControlFile.checkPointCopy.ThisStartUpID = 0;
 394         ControlFile.checkPointCopy.nextXid = (TransactionId) 514;       /* XXX */
 395         ControlFile.checkPointCopy.nextOid = BootstrapObjectIdData;
 396         ControlFile.checkPointCopy.time = time(NULL);
 397
 398         ControlFile.state = DB_SHUTDOWNED;
 399         ControlFile.time = time(NULL);
 400         ControlFile.logId = 0;
 401         ControlFile.logSeg = 1;
 402         ControlFile.checkPoint = ControlFile.checkPointCopy.redo;
 403
 404         ControlFile.blcksz = BLCKSZ;
 405         ControlFile.relseg_size = RELSEG_SIZE;
 406         ControlFile.xlog_seg_size = XLOG_SEG_SIZE;
 407         ControlFile.nameDataLen = NAMEDATALEN;
 408         ControlFile.funcMaxArgs = FUNC_MAX_ARGS;
 409 #ifdef HAVE_INT64_TIMESTAMP
 410         ControlFile.enableIntTimes = TRUE;
 411 #else
 412         ControlFile.enableIntTimes = FALSE;
 413 #endif
 414         ControlFile.localeBuflen = LOCALE_NAME_BUFLEN;
 415
 416         localeptr = setlocale(LC_COLLATE, "");
 417         if (!localeptr)
 418         {
 419                 fprintf(stderr, _("%s: invalid LC_COLLATE setting\n"), progname);
 420                 exit(1);
 421         }
 422         StrNCpy(ControlFile.lc_collate, localeptr, LOCALE_NAME_BUFLEN);
 423         localeptr = setlocale(LC_CTYPE, "");
 424         if (!localeptr)
 425         {
 426                 fprintf(stderr, _("%s: invalid LC_CTYPE setting\n"), progname);
 427                 exit(1);
 428         }
 429         StrNCpy(ControlFile.lc_ctype, localeptr, LOCALE_NAME_BUFLEN);
 430
 431         /*
 432          * XXX eventually, should try to grovel through old XLOG to develop
 433          * more accurate values for startupid, nextXID, and nextOID.
 434          */
 435 }
 436
 437
 438 /*
 439  * Print the guessed pg_control values when we had to guess.
 440  *
 441  * NB: this display should be just those fields that will not be
 442  * reset by RewriteControlFile().
 443  */
 444 static void
 445 PrintControlValues(bool guessed)
 446 {
 447         char            sysident_str[32];
 448
 449         if (guessed)
 450                 printf(_("Guessed pg_control values:\n\n"));
 451         else
 452                 printf(_("pg_control values:\n\n"));
 453
 454         /*
 455          * Format system_identifier separately to keep platform-dependent format
 456          * code out of the translatable message string.
 457          */
 458         snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT,
 459                          ControlFile.system_identifier);
 460
 461         printf(_("pg_control version number:            %u\n"), ControlFile.pg_control_version);
 462         printf(_("Catalog version number:               %u\n"), ControlFile.catalog_version_no);
 463         printf(_("Database system identifier:           %s\n"), sysident_str);
 464         printf(_("Current log file ID:                  %u\n"), ControlFile.logId);
 465         printf(_("Next log file segment:                %u\n"), ControlFile.logSeg);
 466         printf(_("Latest checkpoint's StartUpID:        %u\n"), ControlFile.checkPointCopy.ThisStartUpID);
 467         printf(_("Latest checkpoint's NextXID:          %u\n"), ControlFile.checkPointCopy.nextXid);
 468         printf(_("Latest checkpoint's NextOID:          %u\n"), ControlFile.checkPointCopy.nextOid);
 469         printf(_("Database block size:                  %u\n"), ControlFile.blcksz);
 470         printf(_("Blocks per segment of large relation: %u\n"), ControlFile.relseg_size);
 471         printf(_("Maximum length of identifiers:        %u\n"), ControlFile.nameDataLen);
 472         printf(_("Maximum number of function arguments: %u\n"), ControlFile.funcMaxArgs);
 473         printf(_("Date/time type storage:               %s\n"),
 474                    (ControlFile.enableIntTimes ? _("64-bit integers") : _("floating-point numbers")));
 475         printf(_("Maximum length of locale name:        %u\n"), ControlFile.localeBuflen);
 476         printf(_("LC_COLLATE:                           %s\n"), ControlFile.lc_collate);
 477         printf(_("LC_CTYPE:                             %s\n"), ControlFile.lc_ctype);
 478 }
 479
 480
 481 /*
 482  * Write out the new pg_control file.
 483  */
 484 static void
 485 RewriteControlFile(void)
 486 {
 487         int                     fd;
 488         char            buffer[BLCKSZ]; /* need not be aligned */
 489
 490         /*
 491          * Adjust fields as needed to force an empty XLOG starting at the next
 492          * available segment.
 493          */
 494         newXlogId = ControlFile.logId;
 495         newXlogSeg = ControlFile.logSeg;
 496
 497         /* adjust in case we are changing segment size */
 498         newXlogSeg *= ControlFile.xlog_seg_size;
 499         newXlogSeg = (newXlogSeg + XLogSegSize-1) / XLogSegSize;
 500
 501         /* be sure we wrap around correctly at end of a logfile */
 502         NextLogSeg(newXlogId, newXlogSeg);
 503
 504         /* Now we can force the recorded xlog seg size to the right thing. */
 505         ControlFile.xlog_seg_size = XLogSegSize;
 506
 507         ControlFile.checkPointCopy.redo.xlogid = newXlogId;
 508         ControlFile.checkPointCopy.redo.xrecoff =
 509                 newXlogSeg * XLogSegSize + SizeOfXLogPHD + SizeOfXLogRecord + SizeOfXLogFHD;
 510         ControlFile.checkPointCopy.undo = ControlFile.checkPointCopy.redo;
 511         ControlFile.checkPointCopy.time = time(NULL);
 512
 513         ControlFile.state = DB_SHUTDOWNED;
 514         ControlFile.time = time(NULL);
 515         ControlFile.logId = newXlogId;
 516         ControlFile.logSeg = newXlogSeg + 1;
 517         ControlFile.checkPoint = ControlFile.checkPointCopy.redo;
 518         ControlFile.prevCheckPoint.xlogid = 0;
 519         ControlFile.prevCheckPoint.xrecoff = 0;
 520
 521         /* Contents are protected with a CRC */
 522         INIT_CRC64(ControlFile.crc);
 523         COMP_CRC64(ControlFile.crc,
 524                            (char *) &ControlFile + sizeof(crc64),
 525                            sizeof(ControlFileData) - sizeof(crc64));
 526         FIN_CRC64(ControlFile.crc);
 527
 528         /*
 529          * We write out BLCKSZ bytes into pg_control, zero-padding the excess
 530          * over sizeof(ControlFileData).  This reduces the odds of
 531          * premature-EOF errors when reading pg_control.  We'll still fail
 532          * when we check the contents of the file, but hopefully with a more
 533          * specific error than "couldn't read pg_control".
 534          */
 535         if (sizeof(ControlFileData) > BLCKSZ)
 536         {
 537                 fprintf(stderr,
 538                                 _("%s: internal error -- sizeof(ControlFileData) is too large ... fix xlog.c\n"),
 539                                 progname);
 540                 exit(1);
 541         }
 542
 543         memset(buffer, 0, BLCKSZ);
 544         memcpy(buffer, &ControlFile, sizeof(ControlFileData));
 545
 546         unlink(ControlFilePath);
 547
 548         fd = open(ControlFilePath, O_RDWR | O_CREAT | O_EXCL | PG_BINARY, S_IRUSR | S_IWUSR);
 549         if (fd < 0)
 550         {
 551                 fprintf(stderr, _("%s: could not create pg_control file: %s\n"),
 552                                 progname, strerror(errno));
 553                 exit(1);
 554         }
 555
 556         errno = 0;
 557         if (write(fd, buffer, BLCKSZ) != BLCKSZ)
 558         {
 559                 /* if write didn't set errno, assume problem is no disk space */
 560                 if (errno == 0)
 561                         errno = ENOSPC;
 562                 fprintf(stderr, _("%s: could not write pg_control file: %s\n"),
 563                                 progname, strerror(errno));
 564                 exit(1);
 565         }
 566
 567         if (fsync(fd) != 0)
 568         {
 569                 fprintf(stderr, _("%s: fsync error: %s\n"), progname, strerror(errno));
 570                 exit(1);
 571         }
 572
 573         close(fd);
 574 }
 575
 576
 577 /*
 578  * Remove existing XLOG files
 579  */
 580 static void
 581 KillExistingXLOG(void)
 582 {
 583         DIR                *xldir;
 584         struct dirent *xlde;
 585         char            path[MAXPGPATH];
 586
 587         xldir = opendir(XLogDir);
 588         if (xldir == NULL)
 589         {
 590                 fprintf(stderr, _("%s: could not open directory \"%s\": %s\n"),
 591                                 progname, XLogDir, strerror(errno));
 592                 exit(1);
 593         }
 594
 595         errno = 0;
 596         while ((xlde = readdir(xldir)) != NULL)
 597         {
 598                 if (strlen(xlde->d_name) == 16 &&
 599                         strspn(xlde->d_name, "0123456789ABCDEF") == 16)
 600                 {
 601                         snprintf(path, MAXPGPATH, "%s/%s", XLogDir, xlde->d_name);
 602                         if (unlink(path) < 0)
 603                         {
 604                                 fprintf(stderr, _("%s: could not delete file \"%s\": %s\n"),
 605                                                 progname, path, strerror(errno));
 606                                 exit(1);
 607                         }
 608                 }
 609                 errno = 0;
 610         }
 611 #ifdef WIN32
 612         /* This fix is in mingw cvs (runtime/mingwex/dirent.c rev 1.4), but
 613            not in released version */
 614         if (GetLastError() == ERROR_NO_MORE_FILES)
 615                 errno = 0;
 616 #endif
 617
 618         if (errno)
 619         {
 620                 fprintf(stderr, _("%s: could not read from directory \"%s\": %s\n"),
 621                                 progname, XLogDir, strerror(errno));
 622                 exit(1);
 623         }
 624         closedir(xldir);
 625 }
 626
 627
 628 /*
 629  * Write an empty XLOG file, containing only the checkpoint record
 630  * already set up in ControlFile.
 631  */
 632 static void
 633 WriteEmptyXLOG(void)
 634 {
 635         char       *buffer;
 636         XLogPageHeader page;
 637         XLogRecord *record;
 638         XLogFileHeaderData *fhdr;
 639         crc64           crc;
 640         char            path[MAXPGPATH];
 641         int                     fd;
 642         int                     nbytes;
 643
 644         /* Use malloc() to ensure buffer is MAXALIGNED */
 645         buffer = (char *) malloc(BLCKSZ);
 646         page = (XLogPageHeader) buffer;
 647         memset(buffer, 0, BLCKSZ);
 648
 649         /* Set up the XLOG page header */
 650         page->xlp_magic = XLOG_PAGE_MAGIC;
 651         page->xlp_info = 0;
 652         page->xlp_sui = ControlFile.checkPointCopy.ThisStartUpID;
 653         page->xlp_pageaddr.xlogid =
 654                 ControlFile.checkPointCopy.redo.xlogid;
 655         page->xlp_pageaddr.xrecoff =
 656                 ControlFile.checkPointCopy.redo.xrecoff -
 657                 (SizeOfXLogPHD + SizeOfXLogRecord + SizeOfXLogFHD);
 658
 659         /* Insert the file header record */
 660         record = (XLogRecord *) ((char *) page + SizeOfXLogPHD);
 661         record->xl_prev.xlogid = 0;
 662         record->xl_prev.xrecoff = 0;
 663         record->xl_xact_prev.xlogid = 0;
 664         record->xl_xact_prev.xrecoff = 0;
 665         record->xl_xid = InvalidTransactionId;
 666         record->xl_len = SizeOfXLogFHD;
 667         record->xl_info = XLOG_FILE_HEADER;
 668         record->xl_rmid = RM_XLOG_ID;
 669         fhdr = (XLogFileHeaderData *) XLogRecGetData(record);
 670         fhdr->xlfhd_sysid = ControlFile.system_identifier;
 671         fhdr->xlfhd_xlogid = page->xlp_pageaddr.xlogid;
 672         fhdr->xlfhd_segno = page->xlp_pageaddr.xrecoff / XLogSegSize;
 673         fhdr->xlfhd_seg_size = XLogSegSize;
 674
 675         INIT_CRC64(crc);
 676         COMP_CRC64(crc, fhdr, SizeOfXLogFHD);
 677         COMP_CRC64(crc, (char *) record + sizeof(crc64),
 678                            SizeOfXLogRecord - sizeof(crc64));
 679         FIN_CRC64(crc);
 680         record->xl_crc = crc;
 681
 682         /* Insert the initial checkpoint record */
 683         record = (XLogRecord *) ((char *) page + SizeOfXLogPHD + SizeOfXLogRecord + SizeOfXLogFHD);
 684         record->xl_prev.xlogid = page->xlp_pageaddr.xlogid;
 685         record->xl_prev.xrecoff = page->xlp_pageaddr.xrecoff + SizeOfXLogPHD;
 686         record->xl_xact_prev.xlogid = 0;
 687         record->xl_xact_prev.xrecoff = 0;
 688         record->xl_xid = InvalidTransactionId;
 689         record->xl_len = sizeof(CheckPoint);
 690         record->xl_info = XLOG_CHECKPOINT_SHUTDOWN;
 691         record->xl_rmid = RM_XLOG_ID;
 692         memcpy(XLogRecGetData(record), &ControlFile.checkPointCopy,
 693                    sizeof(CheckPoint));
 694
 695         INIT_CRC64(crc);
 696         COMP_CRC64(crc, &ControlFile.checkPointCopy, sizeof(CheckPoint));
 697         COMP_CRC64(crc, (char *) record + sizeof(crc64),
 698                            SizeOfXLogRecord - sizeof(crc64));
 699         FIN_CRC64(crc);
 700         record->xl_crc = crc;
 701
 702         /* Write the first page */
 703         XLogFileName(path, newXlogId, newXlogSeg);
 704
 705         unlink(path);
 706
 707         fd = open(path, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
 708                           S_IRUSR | S_IWUSR);
 709         if (fd < 0)
 710         {
 711                 fprintf(stderr, _("%s: could not open file \"%s\": %s\n"),
 712                                 progname, path, strerror(errno));
 713                 exit(1);
 714         }
 715
 716         errno = 0;
 717         if (write(fd, buffer, BLCKSZ) != BLCKSZ)
 718         {
 719                 /* if write didn't set errno, assume problem is no disk space */
 720                 if (errno == 0)
 721                         errno = ENOSPC;
 722                 fprintf(stderr, _("%s: could not write file \"%s\": %s\n"),
 723                                 progname, path, strerror(errno));
 724                 exit(1);
 725         }
 726
 727         /* Fill the rest of the file with zeroes */
 728         memset(buffer, 0, BLCKSZ);
 729         for (nbytes = BLCKSZ; nbytes < XLogSegSize; nbytes += BLCKSZ)
 730         {
 731                 errno = 0;
 732                 if (write(fd, buffer, BLCKSZ) != BLCKSZ)
 733                 {
 734                         if (errno == 0)
 735                                 errno = ENOSPC;
 736                         fprintf(stderr, _("%s: could not write file \"%s\": %s\n"),
 737                                         progname, path, strerror(errno));
 738                         exit(1);
 739                 }
 740         }
 741
 742         if (fsync(fd) != 0)
 743         {
 744                 fprintf(stderr, _("%s: fsync error: %s\n"), progname, strerror(errno));
 745                 exit(1);
 746         }
 747
 748         close(fd);
 749 }
 750
 751
 752 static void
 753 usage(void)
 754 {
 755         printf(_("%s resets the PostgreSQL transaction log.\n\n"), progname);
 756         printf(_("Usage:\n  %s [OPTION]... DATADIR\n\n"), progname);
 757         printf(_("Options:\n"));
 758         printf(_("  -f              force update to be done\n"));
 759         printf(_("  -l FILEID,SEG   force minimum WAL starting location for new transaction log\n"));
 760         printf(_("  -n              no update, just show extracted control values (for testing)\n"));
 761         printf(_("  -o OID          set next OID\n"));
 762         printf(_("  -x XID          set next transaction ID\n"));
 763         printf(_("  --help          show this help, then exit\n"));
 764         printf(_("  --version       output version information, then exit\n"));
 765         printf(_("\nReport bugs to <pgsql-bugs@postgresql.org>.\n"));
 766 }