granicus.if.org Git - postgresql/blob - src/backend/utils/adt/tid.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * tid.c--
   4  *        Functions for the built-in type tuple id
   5  *
   6  * Copyright (c) 1994, Regents of the University of California
   7  *
   8  *
   9  * IDENTIFICATION
  10  *        $Header: /cvsroot/pgsql/src/backend/utils/adt/tid.c,v 1.4 1997/09/08 02:31:03 momjian Exp $
  11  *
  12  * NOTES
  13  *        input routine largely stolen from boxin().
  14  *
  15  *-------------------------------------------------------------------------
  16  */
  17 #include <stdio.h>                              /* for sprintf() */
  18 #include <string.h>
  19 #include "postgres.h"
  20 #include "storage/bufpage.h"
  21
  22 #include "utils/palloc.h"
  23 #include "utils/builtins.h"             /* where function declarations go */
  24
  25
  26 #define LDELIM                  '('
  27 #define RDELIM                  ')'
  28 #define DELIM                   ','
  29 #define NTIDARGS                2
  30
  31 /* ----------------------------------------------------------------
  32  *              tidin
  33  * ----------------------------------------------------------------
  34  */
  35 ItemPointer
  36 tidin(char *str)
  37 {
  38         char       *p,
  39                            *coord[NTIDARGS];
  40         int                     i;
  41         ItemPointer result;
  42
  43         BlockNumber blockNumber;
  44         OffsetNumber offsetNumber;
  45
  46         if (str == NULL)
  47                 return NULL;
  48
  49         for (i = 0, p = str; *p && i < NTIDARGS && *p != RDELIM; p++)
  50                 if (*p == DELIM || (*p == LDELIM && !i))
  51                         coord[i++] = p + 1;
  52
  53         if (i < NTIDARGS - 1)
  54                 return NULL;
  55
  56         blockNumber = (BlockNumber) atoi(coord[0]);
  57         offsetNumber = (OffsetNumber) atoi(coord[1]);
  58
  59         result = (ItemPointer) palloc(sizeof(ItemPointerData));
  60
  61         ItemPointerSet(result, blockNumber, offsetNumber);
  62
  63         return result;
  64 }
  65
  66 /* ----------------------------------------------------------------
  67  *              tidout
  68  * ----------------------------------------------------------------
  69  */
  70 char       *
  71 tidout(ItemPointer itemPtr)
  72 {
  73         BlockNumber blockNumber;
  74         OffsetNumber offsetNumber;
  75         BlockId         blockId;
  76         char            buf[32];
  77         char       *str;
  78
  79         blockId = &(itemPtr->ip_blkid);
  80
  81         blockNumber = BlockIdGetBlockNumber(blockId);
  82         offsetNumber = itemPtr->ip_posid;
  83
  84         sprintf(buf, "(%d,%d)", blockNumber, offsetNumber);
  85
  86         str = (char *) palloc(strlen(buf) + 1);
  87         strcpy(str, buf);
  88
  89         return str;
  90 }