Re: [HACKERS] pg_upgrade - Mailing list pgsql-patches

Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Do we want to remove the 7.1beta WAL format code from
> > /contrib/pg_resetxlog?
>
> Sure, I don't think there's any strong need for it anymore.  Anyone who
> did need that version could get it out of the 7.1 release, anyway.

The following patch removes the V0 WAL handling that was there only for
7.1beta.

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
  +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026
Index: contrib/pg_resetxlog/pg_resetxlog.c
===================================================================
RCS file: /cvsroot/pgsql/contrib/pg_resetxlog/pg_resetxlog.c,v
retrieving revision 1.13
diff -c -r1.13 pg_resetxlog.c
*** contrib/pg_resetxlog/pg_resetxlog.c    2002/01/10 20:09:06    1.13
--- contrib/pg_resetxlog/pg_resetxlog.c    2002/01/10 22:37:33
***************
*** 59,106 ****
              (logSeg)++; \
      } while (0)

- /*
-  * Compute ID and segment from an XLogRecPtr.
-  *
-  * For XLByteToSeg, do the computation at face value.  For XLByteToPrevSeg,
-  * a boundary byte is taken to be in the previous segment.    This is suitable
-  * for deciding which segment to write given a pointer to a record end,
-  * for example.
-  */
- #define XLByteToSeg(xlrp, logId, logSeg)    \
-     ( logId = (xlrp).xlogid, \
-       logSeg = (xlrp).xrecoff / XLogSegSize \
-     )
- #define XLByteToPrevSeg(xlrp, logId, logSeg)    \
-     ( logId = (xlrp).xlogid, \
-       logSeg = ((xlrp).xrecoff - 1) / XLogSegSize \
-     )
-
- /*
-  * Is an XLogRecPtr within a particular XLOG segment?
-  *
-  * For XLByteInSeg, do the computation at face value.  For XLByteInPrevSeg,
-  * a boundary byte is taken to be in the previous segment.
-  */
- #define XLByteInSeg(xlrp, logId, logSeg)    \
-     ((xlrp).xlogid == (logId) && \
-      (xlrp).xrecoff / XLogSegSize == (logSeg))
-
- #define XLByteInPrevSeg(xlrp, logId, logSeg)    \
-     ((xlrp).xlogid == (logId) && \
-      ((xlrp).xrecoff - 1) / XLogSegSize == (logSeg))
-
-
  #define XLogFileName(path, log, seg)    \
              snprintf(path, MAXPGPATH, "%s/%08X%08X",    \
                       XLogDir, log, seg)

- /*
-  * _INTL_MAXLOGRECSZ: max space needed for a record including header and
-  * any backup-block data.
-  */
- #define _INTL_MAXLOGRECSZ    (SizeOfXLogRecord + MAXLOGRECSZ + \
-                              XLR_MAX_BKP_BLOCKS * (sizeof(BkpBlock) + BLCKSZ))

  /******************** end of stuff copied from xlog.c ********************/

--- 59,68 ----
***************
*** 115,136 ****
  static bool guessed = false;    /* T if we had to guess at any values */


- static bool CheckControlVersion0(char *buffer, int len);
-
-
- static int
- XLogFileOpen(uint32 log, uint32 seg)
- {
-     char        path[MAXPGPATH];
-     int            fd;
-
-     XLogFileName(path, log, seg);
-
-     fd = open(path, O_RDWR | PG_BINARY, S_IRUSR | S_IWUSR);
-     return (fd);
- }
-
-
  /*
   * Try to read the existing pg_control file.
   *
--- 77,82 ----
***************
*** 174,180 ****
      if (len >= sizeof(ControlFileData) &&
          ((ControlFileData *) buffer)->pg_control_version == PG_CONTROL_VERSION)
      {
!         /* Seems to be current version --- check the CRC. */
          INIT_CRC64(crc);
          COMP_CRC64(crc,
                     buffer + sizeof(crc64),
--- 120,126 ----
      if (len >= sizeof(ControlFileData) &&
          ((ControlFileData *) buffer)->pg_control_version == PG_CONTROL_VERSION)
      {
!         /* Check the CRC. */
          INIT_CRC64(crc);
          COMP_CRC64(crc,
                     buffer + sizeof(crc64),
***************
*** 188,612 ****
              return true;
          }

!         fprintf(stderr, "pg_control exists but has invalid CRC; proceed with caution.\n");
          /* We will use the data anyway, but treat it as guessed. */
          memcpy(&ControlFile, buffer, sizeof(ControlFile));
          guessed = true;
          return true;
      }

-     /*
-      * Maybe it's a 7.1beta pg_control.
-      */
-     if (CheckControlVersion0(buffer, len))
-         return true;
-
      /* Looks like it's a mess. */
      fprintf(stderr, "pg_control exists but is broken or unknown version; ignoring it.\n");
      return false;
  }


- /******************* routines for old XLOG format *******************/
-
-
- /*
-  * This format was in use in 7.1 beta releases through 7.1beta5.  The
-  * pg_control layout was different, and so were the XLOG page headers.
-  * The XLOG record header format was physically the same as 7.1 release,
-  * but interpretation of the xl_len field was not.
-  */
-
- typedef struct crc64V0
- {
-     uint32        crc1;
-     uint32        crc2;
- }    crc64V0;
-
- static uint32 crc_tableV0[] = {
-     0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
-     0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
-     0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
-     0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
-     0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
-     0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
-     0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
-     0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
-     0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
-     0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
-     0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
-     0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
-     0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
-     0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
-     0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
-     0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
-     0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
-     0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
-     0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
-     0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
-     0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
-     0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
-     0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
-     0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
-     0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
-     0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
-     0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
-     0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
-     0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
-     0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
-     0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
-     0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
-     0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
-     0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
-     0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
-     0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
-     0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
-     0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
-     0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
-     0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
-     0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
-     0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
-     0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
- };
-
- #define INIT_CRC64V0(crc)    ((crc).crc1 = 0xffffffff, (crc).crc2 = 0xffffffff)
- #define FIN_CRC64V0(crc)    ((crc).crc1 ^= 0xffffffff, (crc).crc2 ^= 0xffffffff)
- #define COMP_CRC64V0(crc, data, len)    \
- do {\
-         uint32         __c1 = (crc).crc1;\
-         uint32         __c2 = (crc).crc2;\
-         char        *__data = (char *) (data);\
-         uint32         __len = (len);\
- \
-         while (__len >= 2)\
-         {\
-                 __c1 = crc_tableV0[(__c1 ^ *__data++) & 0xff] ^ (__c1 >> 8);\
-                 __c2 = crc_tableV0[(__c2 ^ *__data++) & 0xff] ^ (__c2 >> 8);\
-                 __len -= 2;\
-         }\
-         if (__len > 0)\
-                 __c1 = crc_tableV0[(__c1 ^ *__data++) & 0xff] ^ (__c1 >> 8);\
-         (crc).crc1 = __c1;\
-         (crc).crc2 = __c2;\
- } while (0)
-
- #define EQ_CRC64V0(c1,c2)  ((c1).crc1 == (c2).crc1 && (c1).crc2 == (c2).crc2)
-
-
- #define LOCALE_NAME_BUFLEN_V0  128
-
- typedef struct ControlFileDataV0
- {
-     crc64V0        crc;
-     uint32        logId;            /* current log file id */
-     uint32        logSeg;            /* current log file segment (1-based) */
-     XLogRecPtr    checkPoint;        /* last check point record ptr */
-     time_t        time;            /* time stamp of last modification */
-     DBState        state;            /* see enum above */
-     uint32        blcksz;            /* block size for this DB */
-     uint32        relseg_size;    /* blocks per segment of large relation */
-     uint32        catalog_version_no;        /* internal version number */
-     char        lc_collate[LOCALE_NAME_BUFLEN_V0];
-     char        lc_ctype[LOCALE_NAME_BUFLEN_V0];
-     char        archdir[MAXPGPATH];        /* where to move offline log files */
- }    ControlFileDataV0;
-
- typedef struct CheckPointV0
- {
-     XLogRecPtr    redo;            /* next RecPtr available when we */
-     /* began to create CheckPoint */
-     /* (i.e. REDO start point) */
-     XLogRecPtr    undo;            /* first record of oldest in-progress */
-     /* transaction when we started */
-     /* (i.e. UNDO end point) */
-     StartUpID    ThisStartUpID;
-     TransactionId nextXid;
-     Oid            nextOid;
-     bool        Shutdown;
- }    CheckPointV0;
-
- typedef struct XLogRecordV0
- {
-     crc64V0        xl_crc;
-     XLogRecPtr    xl_prev;        /* ptr to previous record in log */
-     XLogRecPtr    xl_xact_prev;    /* ptr to previous record of this xact */
-     TransactionId xl_xid;        /* xact id */
-     uint16        xl_len;            /* total len of record *data* */
-     uint8        xl_info;
-     RmgrId        xl_rmid;        /* resource manager inserted this record */
- }    XLogRecordV0;
-
- #define SizeOfXLogRecordV0    DOUBLEALIGN(sizeof(XLogRecordV0))
-
- typedef struct XLogContRecordV0
- {
-     uint16        xl_len;            /* len of data left */
- }    XLogContRecordV0;
-
- #define SizeOfXLogContRecordV0    DOUBLEALIGN(sizeof(XLogContRecordV0))
-
- #define XLOG_PAGE_MAGIC_V0 0x17345168
-
- typedef struct XLogPageHeaderDataV0
- {
-     uint32        xlp_magic;
-     uint16        xlp_info;
- }    XLogPageHeaderDataV0;
-
- #define SizeOfXLogPHDV0   DOUBLEALIGN(sizeof(XLogPageHeaderDataV0))
-
- typedef XLogPageHeaderDataV0 *XLogPageHeaderV0;
-
-
- static bool RecordIsValidV0(XLogRecordV0 * record);
- static XLogRecordV0 *ReadRecordV0(XLogRecPtr *RecPtr, char *buffer);
- static bool ValidXLOGHeaderV0(XLogPageHeaderV0 hdr);
-
-
- /*
-  * Try to interpret pg_control contents as "version 0" format.
-  */
- static bool
- CheckControlVersion0(char *buffer, int len)
- {
-     crc64V0        crc;
-     ControlFileDataV0 *oldfile;
-     XLogRecordV0 *record;
-     CheckPointV0 *oldchkpt;
-
-     if (len < sizeof(ControlFileDataV0))
-         return false;
-     /* Check CRC the version-0 way. */
-     INIT_CRC64V0(crc);
-     COMP_CRC64V0(crc,
-                  buffer + sizeof(crc64V0),
-                  sizeof(ControlFileDataV0) - sizeof(crc64V0));
-     FIN_CRC64V0(crc);
-
-     if (!EQ_CRC64V0(crc, ((ControlFileDataV0 *) buffer)->crc))
-         return false;
-
-     /* Valid data, convert useful fields to new-style pg_control format */
-     oldfile = (ControlFileDataV0 *) buffer;
-
-     memset(&ControlFile, 0, sizeof(ControlFile));
-
-     ControlFile.pg_control_version = PG_CONTROL_VERSION;
-     ControlFile.catalog_version_no = oldfile->catalog_version_no;
-
-     ControlFile.state = oldfile->state;
-     ControlFile.logId = oldfile->logId;
-     ControlFile.logSeg = oldfile->logSeg;
-
-     ControlFile.blcksz = oldfile->blcksz;
-     ControlFile.relseg_size = oldfile->relseg_size;
-     strcpy(ControlFile.lc_collate, oldfile->lc_collate);
-     strcpy(ControlFile.lc_ctype, oldfile->lc_ctype);
-
-     /*
-      * Since this format did not include a copy of the latest checkpoint
-      * record, we have to go rooting in the old XLOG to get that.
-      */
-     record = ReadRecordV0(&oldfile->checkPoint,
-                           (char *) malloc(_INTL_MAXLOGRECSZ));
-     if (record == NULL)
-     {
-         /*
-          * We have to guess at the checkpoint contents.
-          */
-         guessed = true;
-         ControlFile.checkPointCopy.ThisStartUpID = 0;
-         ControlFile.checkPointCopy.nextXid = (TransactionId) 514;        /* XXX */
-         ControlFile.checkPointCopy.nextOid = BootstrapObjectIdData;
-         return true;
-     }
-     oldchkpt = (CheckPointV0 *) XLogRecGetData(record);
-
-     ControlFile.checkPointCopy.ThisStartUpID = oldchkpt->ThisStartUpID;
-     ControlFile.checkPointCopy.nextXid = oldchkpt->nextXid;
-     ControlFile.checkPointCopy.nextOid = oldchkpt->nextOid;
-
-     return true;
- }
-
- /*
-  * CRC-check an XLOG V0 record.  We do not believe the contents of an XLOG
-  * record (other than to the minimal extent of computing the amount of
-  * data to read in) until we've checked the CRCs.
-  *
-  * We assume all of the record has been read into memory at *record.
-  */
- static bool
- RecordIsValidV0(XLogRecordV0 * record)
- {
-     crc64V0        crc;
-     uint32        len = record->xl_len;
-
-     /*
-      * NB: this code is not right for V0 records containing backup blocks,
-      * but for now it's only going to be applied to checkpoint records, so
-      * I'm not going to worry about it...
-      */
-     INIT_CRC64V0(crc);
-     COMP_CRC64V0(crc, XLogRecGetData(record), len);
-     COMP_CRC64V0(crc, (char *) record + sizeof(crc64V0),
-                  SizeOfXLogRecordV0 - sizeof(crc64V0));
-     FIN_CRC64V0(crc);
-
-     if (!EQ_CRC64V0(record->xl_crc, crc))
-         return false;
-
-     return (true);
- }
-
- /*
-  * Attempt to read an XLOG V0 record at recptr.
-  *
-  * If no valid record is available, returns NULL.
-  *
-  * buffer is a workspace at least _INTL_MAXLOGRECSZ bytes long.  It is needed
-  * to reassemble a record that crosses block boundaries.  Note that on
-  * successful return, the returned record pointer always points at buffer.
-  */
- static XLogRecordV0 *
- ReadRecordV0(XLogRecPtr *RecPtr, char *buffer)
- {
-     static int    readFile = -1;
-     static uint32 readId = 0;
-     static uint32 readSeg = 0;
-     static uint32 readOff = 0;
-     static char *readBuf = NULL;
-
-     XLogRecordV0 *record;
-     uint32        len,
-                 total_len;
-     uint32        targetPageOff;
-
-     if (readBuf == NULL)
-         readBuf = (char *) malloc(BLCKSZ);
-
-     XLByteToSeg(*RecPtr, readId, readSeg);
-     if (readFile < 0)
-     {
-         readFile = XLogFileOpen(readId, readSeg);
-         if (readFile < 0)
-             goto next_record_is_invalid;
-         readOff = (uint32) (-1);    /* force read to occur below */
-     }
-
-     targetPageOff = ((RecPtr->xrecoff % XLogSegSize) / BLCKSZ) * BLCKSZ;
-     if (readOff != targetPageOff)
-     {
-         readOff = targetPageOff;
-         if (lseek(readFile, (off_t) readOff, SEEK_SET) < 0)
-             goto next_record_is_invalid;
-         if (read(readFile, readBuf, BLCKSZ) != BLCKSZ)
-             goto next_record_is_invalid;
-         if (!ValidXLOGHeaderV0((XLogPageHeaderV0) readBuf))
-             goto next_record_is_invalid;
-     }
-     if ((((XLogPageHeaderV0) readBuf)->xlp_info & XLP_FIRST_IS_CONTRECORD) &&
-         RecPtr->xrecoff % BLCKSZ == SizeOfXLogPHDV0)
-         goto next_record_is_invalid;
-     record = (XLogRecordV0 *) ((char *) readBuf + RecPtr->xrecoff % BLCKSZ);
-
-     if (record->xl_len == 0)
-         goto next_record_is_invalid;
-
-     /*
-      * Compute total length of record including any appended backup
-      * blocks.
-      */
-     total_len = SizeOfXLogRecordV0 + record->xl_len;
-
-     /*
-      * Make sure it will fit in buffer (currently, it is mechanically
-      * impossible for this test to fail, but it seems like a good idea
-      * anyway).
-      */
-     if (total_len > _INTL_MAXLOGRECSZ)
-         goto next_record_is_invalid;
-     len = BLCKSZ - RecPtr->xrecoff % BLCKSZ;
-     if (total_len > len)
-     {
-         /* Need to reassemble record */
-         XLogContRecordV0 *contrecord;
-         uint32        gotlen = len;
-
-         memcpy(buffer, record, len);
-         record = (XLogRecordV0 *) buffer;
-         buffer += len;
-         for (;;)
-         {
-             readOff += BLCKSZ;
-             if (readOff >= XLogSegSize)
-             {
-                 close(readFile);
-                 readFile = -1;
-                 NextLogSeg(readId, readSeg);
-                 readFile = XLogFileOpen(readId, readSeg);
-                 if (readFile < 0)
-                     goto next_record_is_invalid;
-                 readOff = 0;
-             }
-             if (read(readFile, readBuf, BLCKSZ) != BLCKSZ)
-                 goto next_record_is_invalid;
-             if (!ValidXLOGHeaderV0((XLogPageHeaderV0) readBuf))
-                 goto next_record_is_invalid;
-             if (!(((XLogPageHeaderV0) readBuf)->xlp_info & XLP_FIRST_IS_CONTRECORD))
-                 goto next_record_is_invalid;
-             contrecord = (XLogContRecordV0 *) ((char *) readBuf + SizeOfXLogPHDV0);
-             if (contrecord->xl_len == 0 ||
-                 total_len != (contrecord->xl_len + gotlen))
-                 goto next_record_is_invalid;
-             len = BLCKSZ - SizeOfXLogPHDV0 - SizeOfXLogContRecordV0;
-             if (contrecord->xl_len > len)
-             {
-                 memcpy(buffer, (char *) contrecord + SizeOfXLogContRecordV0, len);
-                 gotlen += len;
-                 buffer += len;
-                 continue;
-             }
-             memcpy(buffer, (char *) contrecord + SizeOfXLogContRecordV0,
-                    contrecord->xl_len);
-             break;
-         }
-         if (!RecordIsValidV0(record))
-             goto next_record_is_invalid;
-         return record;
-     }
-
-     /* Record does not cross a page boundary */
-     if (!RecordIsValidV0(record))
-         goto next_record_is_invalid;
-     memcpy(buffer, record, total_len);
-     return (XLogRecordV0 *) buffer;
-
- next_record_is_invalid:;
-     close(readFile);
-     readFile = -1;
-     return NULL;
- }
-
- /*
-  * Check whether the xlog header of a page just read in looks valid.
-  *
-  * This is just a convenience subroutine to avoid duplicated code in
-  * ReadRecord.    It's not intended for use from anywhere else.
-  */
- static bool
- ValidXLOGHeaderV0(XLogPageHeaderV0 hdr)
- {
-     if (hdr->xlp_magic != XLOG_PAGE_MAGIC_V0)
-         return false;
-     if ((hdr->xlp_info & ~XLP_ALL_FLAGS) != 0)
-         return false;
-     return true;
- }
-
- /******************* end of routines for old XLOG format *******************/
-
-
  /*
   * Guess at pg_control values when we can't read the old ones.
   */
--- 134,152 ----
              return true;
          }

!         fprintf(stderr, "pg_control exists but has invalid CRC; proceeding with caution.\n");
          /* We will use the data anyway, but treat it as guessed. */
          memcpy(&ControlFile, buffer, sizeof(ControlFile));
          guessed = true;
          return true;
      }

      /* Looks like it's a mess. */
      fprintf(stderr, "pg_control exists but is broken or unknown version; ignoring it.\n");
      return false;
  }


  /*
   * Guess at pg_control values when we can't read the old ones.
   */
***************
*** 676,684 ****
   * reset by RewriteControlFile().
   */
  static void
! PrintControlValues(void)
  {
!     printf("Guessed-at pg_control values:\n\n"
             "pg_control version number:            %u\n"
             "Catalog version number:               %u\n"
             "Current log file id:                  %u\n"
--- 216,224 ----
   * reset by RewriteControlFile().
   */
  static void
! PrintControlValues(bool guessed)
  {
!     printf("\n%spg_control values:\n\n"
             "pg_control version number:            %u\n"
             "Catalog version number:               %u\n"
             "Current log file id:                  %u\n"
***************
*** 692,697 ****
--- 232,238 ----
             "LC_COLLATE:                           %s\n"
             "LC_CTYPE:                             %s\n",

+            (guessed ? "Guessed-at " : ""),
             ControlFile.pg_control_version,
             ControlFile.catalog_version_no,
             ControlFile.logId,
***************
*** 1042,1048 ****
       */
      if ((guessed && !force) || noupdate)
      {
!         PrintControlValues();
          if (!noupdate)
              printf("\nIf these values seem acceptable, use -f to force reset.\n");
          exit(1);
--- 583,589 ----
       */
      if ((guessed && !force) || noupdate)
      {
!         PrintControlValues(guessed);
          if (!noupdate)
              printf("\nIf these values seem acceptable, use -f to force reset.\n");
          exit(1);