87 lines
2.1 KiB
C
87 lines
2.1 KiB
C
/*-------------------------------------------------------------------------
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*
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* xid.c
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* POSTGRES transaction identifier type.
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*
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: xid.c,v 1.29 2001/01/24 19:42:51 momjian Exp $
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*
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* OLD COMMENTS
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* XXX WARNING
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* Much of this file will change when we change our representation
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* of transaction ids -cim 3/23/90
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*
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* It is time to make the switch from 5 byte to 4 byte transaction ids
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* This file was totally reworked. -mer 5/22/92
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "access/xact.h"
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/*
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* TransactionId is typedef'd as uint32, so...
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*/
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#define PG_GETARG_TRANSACTIONID(n) PG_GETARG_UINT32(n)
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#define PG_RETURN_TRANSACTIONID(x) PG_RETURN_UINT32(x)
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extern TransactionId NullTransactionId;
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extern TransactionId DisabledTransactionId;
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extern TransactionId AmiTransactionId;
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extern TransactionId FirstTransactionId;
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/* XXX name for catalogs */
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Datum
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xidin(PG_FUNCTION_ARGS)
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{
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char *representation = PG_GETARG_CSTRING(0);
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PG_RETURN_TRANSACTIONID((TransactionId) atol(representation));
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}
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/* XXX name for catalogs */
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Datum
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xidout(PG_FUNCTION_ARGS)
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{
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TransactionId transactionId = PG_GETARG_TRANSACTIONID(0);
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/* maximum 32 bit unsigned integer representation takes 10 chars */
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char *representation = palloc(11);
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snprintf(representation, 11, "%lu", (unsigned long) transactionId);
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PG_RETURN_CSTRING(representation);
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}
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/* ----------------------------------------------------------------
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* xideq
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* ----------------------------------------------------------------
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*/
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/*
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* xideq - returns 1, iff xid1 == xid2
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* 0 else;
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*/
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Datum
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xideq(PG_FUNCTION_ARGS)
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{
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TransactionId xid1 = PG_GETARG_TRANSACTIONID(0);
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TransactionId xid2 = PG_GETARG_TRANSACTIONID(1);
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PG_RETURN_BOOL(xid1 == xid2);
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}
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/* ----------------------------------------------------------------
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* TransactionIdAdd
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* ----------------------------------------------------------------
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*/
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void
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TransactionIdAdd(TransactionId *xid, int value)
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{
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*xid += value;
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}
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