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219d476d8a
CommandId is declared as uint32, and values up to 4G are indeed legal. cidout() handles them properly by treating the value as unsigned int. But cidin() was just using atoi(), which has platform-dependent behavior for values outside the range of signed int, as reported by Bart Lengkeek in bug #14379. Use strtoul() instead, as xidin() does. In passing, make some purely cosmetic changes to make xidin/xidout look more like cidin/cidout; the former didn't have a monopoly on best practice IMO. Neither xidin nor cidin make any attempt to throw error for invalid input. I didn't change that here, and am not sure it's worth worrying about since neither is really a user-facing type. The point is just to ensure that indubitably-valid inputs work as expected. It's been like this for a long time, so back-patch to all supported branches. Report: <20161018152550.1413.6439@wrigleys.postgresql.org>
199 lines
4.3 KiB
C
199 lines
4.3 KiB
C
/*-------------------------------------------------------------------------
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*
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* xid.c
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* POSTGRES transaction identifier and command identifier datatypes.
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*
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* Portions Copyright (c) 1996-2015, 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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*
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* IDENTIFICATION
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* src/backend/utils/adt/xid.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include <limits.h>
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#include "access/multixact.h"
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#include "access/transam.h"
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#include "access/xact.h"
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#include "libpq/pqformat.h"
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#include "utils/builtins.h"
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#define PG_GETARG_TRANSACTIONID(n) DatumGetTransactionId(PG_GETARG_DATUM(n))
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#define PG_RETURN_TRANSACTIONID(x) return TransactionIdGetDatum(x)
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#define PG_GETARG_COMMANDID(n) DatumGetCommandId(PG_GETARG_DATUM(n))
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#define PG_RETURN_COMMANDID(x) return CommandIdGetDatum(x)
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Datum
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xidin(PG_FUNCTION_ARGS)
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{
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char *str = PG_GETARG_CSTRING(0);
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PG_RETURN_TRANSACTIONID((TransactionId) strtoul(str, NULL, 0));
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}
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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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char *result = (char *) palloc(16);
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snprintf(result, 16, "%lu", (unsigned long) transactionId);
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PG_RETURN_CSTRING(result);
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}
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/*
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* xidrecv - converts external binary format to xid
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*/
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Datum
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xidrecv(PG_FUNCTION_ARGS)
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{
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StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
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PG_RETURN_TRANSACTIONID((TransactionId) pq_getmsgint(buf, sizeof(TransactionId)));
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}
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/*
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* xidsend - converts xid to binary format
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*/
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Datum
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xidsend(PG_FUNCTION_ARGS)
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{
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TransactionId arg1 = PG_GETARG_TRANSACTIONID(0);
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StringInfoData buf;
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pq_begintypsend(&buf);
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pq_sendint(&buf, arg1, sizeof(arg1));
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PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
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}
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/*
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* xideq - are two xids equal?
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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(TransactionIdEquals(xid1, xid2));
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}
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/*
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* xid_age - compute age of an XID (relative to latest stable xid)
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*/
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Datum
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xid_age(PG_FUNCTION_ARGS)
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{
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TransactionId xid = PG_GETARG_TRANSACTIONID(0);
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TransactionId now = GetStableLatestTransactionId();
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/* Permanent XIDs are always infinitely old */
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if (!TransactionIdIsNormal(xid))
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PG_RETURN_INT32(INT_MAX);
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PG_RETURN_INT32((int32) (now - xid));
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}
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/*
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* mxid_age - compute age of a multi XID (relative to latest stable mxid)
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*/
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Datum
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mxid_age(PG_FUNCTION_ARGS)
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{
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TransactionId xid = PG_GETARG_TRANSACTIONID(0);
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MultiXactId now = ReadNextMultiXactId();
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if (!MultiXactIdIsValid(xid))
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PG_RETURN_INT32(INT_MAX);
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PG_RETURN_INT32((int32) (now - xid));
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}
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/*
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* xidComparator
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* qsort comparison function for XIDs
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*
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* We can't use wraparound comparison for XIDs because that does not respect
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* the triangle inequality! Any old sort order will do.
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*/
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int
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xidComparator(const void *arg1, const void *arg2)
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{
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TransactionId xid1 = *(const TransactionId *) arg1;
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TransactionId xid2 = *(const TransactionId *) arg2;
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if (xid1 > xid2)
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return 1;
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if (xid1 < xid2)
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return -1;
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return 0;
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}
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/*****************************************************************************
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* COMMAND IDENTIFIER ROUTINES *
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*****************************************************************************/
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/*
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* cidin - converts CommandId to internal representation.
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*/
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Datum
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cidin(PG_FUNCTION_ARGS)
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{
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char *str = PG_GETARG_CSTRING(0);
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PG_RETURN_COMMANDID((CommandId) strtoul(str, NULL, 0));
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}
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/*
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* cidout - converts a cid to external representation.
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*/
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Datum
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cidout(PG_FUNCTION_ARGS)
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{
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CommandId c = PG_GETARG_COMMANDID(0);
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char *result = (char *) palloc(16);
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snprintf(result, 16, "%lu", (unsigned long) c);
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PG_RETURN_CSTRING(result);
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}
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/*
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* cidrecv - converts external binary format to cid
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*/
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Datum
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cidrecv(PG_FUNCTION_ARGS)
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{
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StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
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PG_RETURN_COMMANDID((CommandId) pq_getmsgint(buf, sizeof(CommandId)));
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}
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/*
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* cidsend - converts cid to binary format
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*/
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Datum
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cidsend(PG_FUNCTION_ARGS)
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{
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CommandId arg1 = PG_GETARG_COMMANDID(0);
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StringInfoData buf;
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pq_begintypsend(&buf);
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pq_sendint(&buf, arg1, sizeof(arg1));
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PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
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}
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Datum
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cideq(PG_FUNCTION_ARGS)
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{
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CommandId arg1 = PG_GETARG_COMMANDID(0);
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CommandId arg2 = PG_GETARG_COMMANDID(1);
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PG_RETURN_BOOL(arg1 == arg2);
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}
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