database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-14 18:42:34 +03:00
Code Activity

Massive commit to run PGINDENT on all *.c and *.h files.

Browse Source
This commit is contained in:
Bruce Momjian
1997-09-07 05:04:48 +00:00
parent 8fecd4febf
commit 1ccd423235
687 changed files with 150775 additions and 136888 deletions
Download Patch File Download Diff File Expand all files Collapse all files

212
src/backend/executor/execScan.c
View File

@ -1,17 +1,17 @@
/*-------------------------------------------------------------------------
*
* execScan.c--
* This code provides support for generalized relation scans. ExecScan
* is passed a node and a pointer to a function to "do the right thing"
* and return a tuple from the relation. ExecScan then does the tedious
* stuff - checking the qualification and projecting the tuple
* appropriately.
* This code provides support for generalized relation scans. ExecScan
* is passed a node and a pointer to a function to "do the right thing"
* and return a tuple from the relation. ExecScan then does the tedious
* stuff - checking the qualification and projecting the tuple
* appropriately.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/executor/execScan.c,v 1.3 1997/07/28 00:53:51 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/executor/execScan.c,v 1.4 1997/09/07 04:41:23 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -23,117 +23,123 @@
#include "executor/executor.h"
/* ----------------------------------------------------------------
* ExecScan
*
* Scans the relation using the 'access method' indicated and
* returns the next qualifying tuple in the direction specified
* in the global variable ExecDirection.
* The access method returns the next tuple and execScan() is
* responisble for checking the tuple returned against the qual-clause.
*
* Conditions:
* -- the "cursor" maintained by the AMI is positioned at the tuple
* returned previously.
*
* Initial States:
* -- the relation indicated is opened for scanning so that the
* "cursor" is positioned before the first qualifying tuple.
* ExecScan
*
* May need to put startmmgr and endmmgr in here.
* Scans the relation using the 'access method' indicated and
* returns the next qualifying tuple in the direction specified
* in the global variable ExecDirection.
* The access method returns the next tuple and execScan() is
* responisble for checking the tuple returned against the qual-clause.
*
* Conditions:
* -- the "cursor" maintained by the AMI is positioned at the tuple
* returned previously.
*
* Initial States:
* -- the relation indicated is opened for scanning so that the
* "cursor" is positioned before the first qualifying tuple.
*
* May need to put startmmgr and endmmgr in here.
* ----------------------------------------------------------------
*/
TupleTableSlot *
ExecScan(Scan *node,
TupleTableSlot* (*accessMtd)()) /* function returning a tuple */
ExecScan(Scan * node,
TupleTableSlot * (*accessMtd) ()) /* function returning a
* tuple */
{
CommonScanState *scanstate;
EState *estate;
List *qual;
bool isDone;
CommonScanState *scanstate;
EState *estate;
List *qual;
bool isDone;
TupleTableSlot *slot;
TupleTableSlot *resultSlot;
HeapTuple newTuple;
TupleTableSlot *slot;
TupleTableSlot *resultSlot;
HeapTuple newTuple;
ExprContext *econtext;
ProjectionInfo *projInfo;
ExprContext *econtext;
ProjectionInfo *projInfo;
/* ----------------
* initialize misc variables
* ----------------
*/
newTuple = NULL;
slot = NULL;
/* ----------------
* initialize misc variables
* ----------------
*/
newTuple = NULL;
slot = NULL;
estate = node->plan.state;
scanstate = node->scanstate;
estate = node->plan.state;
scanstate = node->scanstate;
/* ----------------
* get the expression context
* ----------------
*/
econtext = scanstate->cstate.cs_ExprContext;
/* ----------------
* get the expression context
* ----------------
*/
econtext = scanstate->cstate.cs_ExprContext;
/* ----------------
* initialize fields in ExprContext which don't change
* in the course of the scan..
* ----------------
*/
qual = node->plan.qual;
econtext->ecxt_relation = scanstate->css_currentRelation;
econtext->ecxt_relid = node->scanrelid;
/* ----------------
* initialize fields in ExprContext which don't change
* in the course of the scan..
* ----------------
*/
qual = node->plan.qual;
econtext->ecxt_relation = scanstate->css_currentRelation;
econtext->ecxt_relid = node->scanrelid;
if (scanstate->cstate.cs_TupFromTlist) {
if (scanstate->cstate.cs_TupFromTlist)
{
projInfo = scanstate->cstate.cs_ProjInfo;
resultSlot = ExecProject(projInfo, &isDone);
if (!isDone)
return resultSlot;
}
/*
* get a tuple from the access method loop until we obtain a tuple
* which passes the qualification.
*/
for (;;)
{
slot = (TupleTableSlot *) (*accessMtd) (node);
/* ----------------
* if the slot returned by the accessMtd contains
* NULL, then it means there is nothing more to scan
* so we just return the empty slot.
* ----------------
*/
if (TupIsNull(slot))
return slot;
/* ----------------
* place the current tuple into the expr context
* ----------------
*/
econtext->ecxt_scantuple = slot;
/* ----------------
* check that the current tuple satisfies the qual-clause
* if our qualification succeeds then we
* leave the loop.
* ----------------
*/
/*
* add a check for non-nil qual here to avoid a function call to
* ExecQual() when the qual is nil
*/
if (!qual || ExecQual(qual, econtext) == true)
break;
}
/* ----------------
* form a projection tuple, store it in the result tuple
* slot and return it.
* ----------------
*/
projInfo = scanstate->cstate.cs_ProjInfo;
resultSlot = ExecProject(projInfo, &isDone);
if (!isDone)
return resultSlot;
}
/*
* get a tuple from the access method
* loop until we obtain a tuple which passes the qualification.
*/
for(;;) {
slot = (TupleTableSlot *) (*accessMtd)(node);
scanstate->cstate.cs_TupFromTlist = !isDone;
/* ----------------
* if the slot returned by the accessMtd contains
* NULL, then it means there is nothing more to scan
* so we just return the empty slot.
* ----------------
*/
if (TupIsNull(slot)) return slot;
/* ----------------
* place the current tuple into the expr context
* ----------------
*/
econtext->ecxt_scantuple = slot;
/* ----------------
* check that the current tuple satisfies the qual-clause
* if our qualification succeeds then we
* leave the loop.
* ----------------
*/
/* add a check for non-nil qual here to avoid a
function call to ExecQual() when the qual is nil */
if (!qual || ExecQual(qual, econtext) == true)
break;
}
/* ----------------
* form a projection tuple, store it in the result tuple
* slot and return it.
* ----------------
*/
projInfo = scanstate->cstate.cs_ProjInfo;
resultSlot = ExecProject(projInfo, &isDone);
scanstate->cstate.cs_TupFromTlist = !isDone;
return resultSlot;
return resultSlot;
}