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/*-------------------------------------------------------------------------
*
* spi.c
* Server Programming Interface
*
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/executor/spi.c,v 1.82 2002/12/17 15:51:59 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/printtup.h"
#include "catalog/heap.h"
#include "commands/portalcmds.h"
#include "executor/spi_priv.h"
#include "tcop/tcopprot.h"
#include "utils/lsyscache.h"
uint32 SPI_processed = 0;
Oid SPI_lastoid = InvalidOid;
SPITupleTable *SPI_tuptable = NULL;
int SPI_result;
static _SPI_connection *_SPI_stack = NULL;
static _SPI_connection *_SPI_current = NULL;
static int _SPI_connected = -1;
static int _SPI_curid = -1;
static int _SPI_execute(char *src, int tcount, _SPI_plan *plan);
static int _SPI_pquery(QueryDesc *queryDesc, bool runit, int tcount);
static int _SPI_execute_plan(_SPI_plan *plan,
Datum *Values, char *Nulls, int tcount);
static void _SPI_cursor_operation(Portal portal, bool forward, int count,
CommandDest dest);
static _SPI_plan *_SPI_copy_plan(_SPI_plan *plan, int location);
static int _SPI_begin_call(bool execmem);
static int _SPI_end_call(bool procmem);
static MemoryContext _SPI_execmem(void);
static MemoryContext _SPI_procmem(void);
static bool _SPI_checktuples(void);
/* =================== interface functions =================== */
int
SPI_connect(void)
{
_SPI_connection *new_SPI_stack;
/*
* When procedure called by Executor _SPI_curid expected to be equal
* to _SPI_connected
*/
if (_SPI_curid != _SPI_connected)
return SPI_ERROR_CONNECT;
if (_SPI_stack == NULL)
{
if (_SPI_connected != -1)
elog(FATAL, "SPI_connect: no connection(s) expected");
new_SPI_stack = (_SPI_connection *) malloc(sizeof(_SPI_connection));
}
else
{
if (_SPI_connected <= -1)
elog(FATAL, "SPI_connect: some connection(s) expected");
new_SPI_stack = (_SPI_connection *) realloc(_SPI_stack,
(_SPI_connected + 2) * sizeof(_SPI_connection));
}
if (new_SPI_stack == NULL)
elog(ERROR, "Memory exhausted in SPI_connect");
/*
* We' returning to procedure where _SPI_curid == _SPI_connected - 1
*/
_SPI_stack = new_SPI_stack;
_SPI_connected++;
_SPI_current = &(_SPI_stack[_SPI_connected]);
_SPI_current->processed = 0;
_SPI_current->tuptable = NULL;
/* Create memory contexts for this procedure */
_SPI_current->procCxt = AllocSetContextCreate(TopTransactionContext,
"SPI Proc",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
_SPI_current->execCxt = AllocSetContextCreate(TopTransactionContext,
"SPI Exec",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
/* ... and switch to procedure's context */
_SPI_current->savedcxt = MemoryContextSwitchTo(_SPI_current->procCxt);
return SPI_OK_CONNECT;
}
int
SPI_finish(void)
{
int res;
res = _SPI_begin_call(false); /* live in procedure memory */
if (res < 0)
return res;
/* Restore memory context as it was before procedure call */
MemoryContextSwitchTo(_SPI_current->savedcxt);
/* Release memory used in procedure call */
MemoryContextDelete(_SPI_current->execCxt);
MemoryContextDelete(_SPI_current->procCxt);
/*
* After _SPI_begin_call _SPI_connected == _SPI_curid. Now we are
* closing connection to SPI and returning to upper Executor and so
* _SPI_connected must be equal to _SPI_curid.
*/
_SPI_connected--;
_SPI_curid--;
if (_SPI_connected == -1)
{
free(_SPI_stack);
_SPI_stack = NULL;
_SPI_current = NULL;
}
else
{
_SPI_connection *new_SPI_stack;
new_SPI_stack = (_SPI_connection *) realloc(_SPI_stack,
(_SPI_connected + 1) * sizeof(_SPI_connection));
/* This could only fail with a pretty stupid malloc package ... */
if (new_SPI_stack == NULL)
elog(ERROR, "Memory exhausted in SPI_finish");
_SPI_stack = new_SPI_stack;
_SPI_current = &(_SPI_stack[_SPI_connected]);
}
return SPI_OK_FINISH;
}
/*
* Clean up SPI state at transaction commit or abort (we don't care which).
*/
void
AtEOXact_SPI(void)
{
/*
* Note that memory contexts belonging to SPI stack entries will be
* freed automatically, so we can ignore them here. We just need to
* restore our static variables to initial state.
*/
if (_SPI_stack != NULL) /* there was abort */
free(_SPI_stack);
_SPI_current = _SPI_stack = NULL;
_SPI_connected = _SPI_curid = -1;
SPI_processed = 0;
SPI_lastoid = InvalidOid;
SPI_tuptable = NULL;
}
void
SPI_push(void)
{
_SPI_curid++;
}
void
SPI_pop(void)
{
_SPI_curid--;
}
int
SPI_exec(char *src, int tcount)
{
int res;
if (src == NULL || tcount < 0)
return SPI_ERROR_ARGUMENT;
res = _SPI_begin_call(true);
if (res < 0)
return res;
res = _SPI_execute(src, tcount, NULL);
_SPI_end_call(true);
return res;
}
int
SPI_execp(void *plan, Datum *Values, char *Nulls, int tcount)
{
int res;
if (plan == NULL || tcount < 0)
return SPI_ERROR_ARGUMENT;
if (((_SPI_plan *) plan)->nargs > 0 && Values == NULL)
return SPI_ERROR_PARAM;
res = _SPI_begin_call(true);
if (res < 0)
return res;
res = _SPI_execute_plan((_SPI_plan *) plan, Values, Nulls, tcount);
_SPI_end_call(true);
return res;
}
void *
SPI_prepare(char *src, int nargs, Oid *argtypes)
{
_SPI_plan *plan;
if (src == NULL || nargs < 0 || (nargs > 0 && argtypes == NULL))
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
SPI_result = _SPI_begin_call(true);
if (SPI_result < 0)
return NULL;
plan = (_SPI_plan *) palloc(sizeof(_SPI_plan)); /* Executor context */
plan->argtypes = argtypes;
plan->nargs = nargs;
SPI_result = _SPI_execute(src, 0, plan);
if (SPI_result >= 0) /* copy plan to procedure context */
plan = _SPI_copy_plan(plan, _SPI_CPLAN_PROCXT);
else
plan = NULL;
_SPI_end_call(true);
return (void *) plan;
}
void *
SPI_saveplan(void *plan)
{
_SPI_plan *newplan;
if (plan == NULL)
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
SPI_result = _SPI_begin_call(false); /* don't change context */
if (SPI_result < 0)
return NULL;
newplan = _SPI_copy_plan((_SPI_plan *) plan, _SPI_CPLAN_TOPCXT);
_SPI_curid--;
SPI_result = 0;
return (void *) newplan;
}
int
SPI_freeplan(void *plan)
{
_SPI_plan *spiplan = (_SPI_plan *) plan;
if (plan == NULL)
return SPI_ERROR_ARGUMENT;
MemoryContextDelete(spiplan->plancxt);
return 0;
}
HeapTuple
SPI_copytuple(HeapTuple tuple)
{
MemoryContext oldcxt = NULL;
HeapTuple ctuple;
if (tuple == NULL)
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
if (_SPI_curid + 1 == _SPI_connected) /* connected */
{
if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
elog(FATAL, "SPI: stack corrupted");
oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
}
ctuple = heap_copytuple(tuple);
if (oldcxt)
MemoryContextSwitchTo(oldcxt);
return ctuple;
}
TupleDesc
SPI_copytupledesc(TupleDesc tupdesc)
{
MemoryContext oldcxt = NULL;
TupleDesc ctupdesc;
if (tupdesc == NULL)
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
if (_SPI_curid + 1 == _SPI_connected) /* connected */
{
if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
elog(FATAL, "SPI: stack corrupted");
oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
}
ctupdesc = CreateTupleDescCopy(tupdesc);
if (oldcxt)
MemoryContextSwitchTo(oldcxt);
return ctupdesc;
}
TupleTableSlot *
SPI_copytupleintoslot(HeapTuple tuple, TupleDesc tupdesc)
{
MemoryContext oldcxt = NULL;
TupleTableSlot *cslot;
HeapTuple ctuple;
TupleDesc ctupdesc;
if (tuple == NULL || tupdesc == NULL)
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
if (_SPI_curid + 1 == _SPI_connected) /* connected */
{
if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
elog(FATAL, "SPI: stack corrupted");
oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
}
ctuple = heap_copytuple(tuple);
ctupdesc = CreateTupleDescCopy(tupdesc);
cslot = MakeTupleTableSlot();
ExecSetSlotDescriptor(cslot, ctupdesc, true);
cslot = ExecStoreTuple(ctuple, cslot, InvalidBuffer, true);
if (oldcxt)
MemoryContextSwitchTo(oldcxt);
return cslot;
}
HeapTuple
SPI_modifytuple(Relation rel, HeapTuple tuple, int natts, int *attnum,
Datum *Values, char *Nulls)
{
MemoryContext oldcxt = NULL;
HeapTuple mtuple;
int numberOfAttributes;
Datum *v;
char *n;
bool isnull;
int i;
if (rel == NULL || tuple == NULL || natts <= 0 || attnum == NULL || Values == NULL)
{
SPI_result = SPI_ERROR_ARGUMENT;
return NULL;
}
if (_SPI_curid + 1 == _SPI_connected) /* connected */
{
if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
elog(FATAL, "SPI: stack corrupted");
oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
}
SPI_result = 0;
numberOfAttributes = rel->rd_att->natts;
v = (Datum *) palloc(numberOfAttributes * sizeof(Datum));
n = (char *) palloc(numberOfAttributes * sizeof(char));
/* fetch old values and nulls */
for (i = 0; i < numberOfAttributes; i++)
{
v[i] = heap_getattr(tuple, i + 1, rel->rd_att, &isnull);
n[i] = (isnull) ? 'n' : ' ';
}
/* replace values and nulls */
for (i = 0; i < natts; i++)
{
if (attnum[i] <= 0 || attnum[i] > numberOfAttributes)
break;
v[attnum[i] - 1] = Values[i];
n[attnum[i] - 1] = (Nulls && Nulls[i] == 'n') ? 'n' : ' ';
}
if (i == natts) /* no errors in *attnum */
{
mtuple = heap_formtuple(rel->rd_att, v, n);
/*
* copy the identification info of the old tuple: t_ctid, t_self,
* and OID (if any)
*/
mtuple->t_data->t_ctid = tuple->t_data->t_ctid;
mtuple->t_self = tuple->t_self;
mtuple->t_tableOid = tuple->t_tableOid;
if (rel->rd_rel->relhasoids)
HeapTupleSetOid(mtuple, HeapTupleGetOid(tuple));
}
else
{
mtuple = NULL;
SPI_result = SPI_ERROR_NOATTRIBUTE;
}
pfree(v);
pfree(n);
if (oldcxt)
MemoryContextSwitchTo(oldcxt);
return mtuple;
}
int
SPI_fnumber(TupleDesc tupdesc, char *fname)
{
int res;
Form_pg_attribute sysatt;
for (res = 0; res < tupdesc->natts; res++)
{
if (namestrcmp(&tupdesc->attrs[res]->attname, fname) == 0)
return res + 1;
}
sysatt = SystemAttributeByName(fname, true /* "oid" will be accepted */ );
if (sysatt != NULL)
return sysatt->attnum;
/* SPI_ERROR_NOATTRIBUTE is different from all sys column numbers */
return SPI_ERROR_NOATTRIBUTE;
}
char *
SPI_fname(TupleDesc tupdesc, int fnumber)
{
Form_pg_attribute att;
SPI_result = 0;
if (fnumber > tupdesc->natts || fnumber == 0 ||
fnumber <= FirstLowInvalidHeapAttributeNumber)
{
SPI_result = SPI_ERROR_NOATTRIBUTE;
return NULL;
}
if (fnumber > 0)
att = tupdesc->attrs[fnumber - 1];
else
att = SystemAttributeDefinition(fnumber, true);
return pstrdup(NameStr(att->attname));
}
char *
SPI_getvalue(HeapTuple tuple, TupleDesc tupdesc, int fnumber)
{
Datum origval,
val,
result;
bool isnull;
Oid typoid,
foutoid,
typelem;
int32 typmod;
bool typisvarlena;
SPI_result = 0;
if (fnumber > tuple->t_data->t_natts || fnumber == 0 ||
fnumber <= FirstLowInvalidHeapAttributeNumber)
{
SPI_result = SPI_ERROR_NOATTRIBUTE;
return NULL;
}
origval = heap_getattr(tuple, fnumber, tupdesc, &isnull);
if (isnull)
return NULL;
if (fnumber > 0)
{
typoid = tupdesc->attrs[fnumber - 1]->atttypid;
typmod = tupdesc->attrs[fnumber - 1]->atttypmod;
}
else
{
typoid = (SystemAttributeDefinition(fnumber, true))->atttypid;
typmod = -1;
}
if (!getTypeOutputInfo(typoid, &foutoid, &typelem, &typisvarlena))
{
SPI_result = SPI_ERROR_NOOUTFUNC;
return NULL;
}
/*
* If we have a toasted datum, forcibly detoast it here to avoid
* memory leakage inside the type's output routine.
*/
if (typisvarlena)
val = PointerGetDatum(PG_DETOAST_DATUM(origval));
else
val = origval;
result = OidFunctionCall3(foutoid,
val,
ObjectIdGetDatum(typelem),
Int32GetDatum(typmod));
/* Clean up detoasted copy, if any */
if (val != origval)
pfree(DatumGetPointer(val));
return DatumGetCString(result);
}
Datum
SPI_getbinval(HeapTuple tuple, TupleDesc tupdesc, int fnumber, bool *isnull)
{
SPI_result = 0;
if (fnumber > tuple->t_data->t_natts || fnumber == 0 ||
fnumber <= FirstLowInvalidHeapAttributeNumber)
{
SPI_result = SPI_ERROR_NOATTRIBUTE;
*isnull = true;
return (Datum) NULL;
}
return heap_getattr(tuple, fnumber, tupdesc, isnull);
}
char *
SPI_gettype(TupleDesc tupdesc, int fnumber)
{
Oid typoid;
HeapTuple typeTuple;
char *result;
SPI_result = 0;
if (fnumber > tupdesc->natts || fnumber == 0 ||
fnumber <= FirstLowInvalidHeapAttributeNumber)
{
SPI_result = SPI_ERROR_NOATTRIBUTE;
return NULL;
}
if (fnumber > 0)
typoid = tupdesc->attrs[fnumber - 1]->atttypid;
else
typoid = (SystemAttributeDefinition(fnumber, true))->atttypid;
typeTuple = SearchSysCache(TYPEOID,
ObjectIdGetDatum(typoid),
0, 0, 0);
if (!HeapTupleIsValid(typeTuple))
{
SPI_result = SPI_ERROR_TYPUNKNOWN;
return NULL;
}
result = pstrdup(NameStr(((Form_pg_type) GETSTRUCT(typeTuple))->typname));
ReleaseSysCache(typeTuple);
return result;
}
Oid
SPI_gettypeid(TupleDesc tupdesc, int fnumber)
{
SPI_result = 0;
if (fnumber > tupdesc->natts || fnumber == 0 ||
fnumber <= FirstLowInvalidHeapAttributeNumber)
{
SPI_result = SPI_ERROR_NOATTRIBUTE;
return InvalidOid;
}
if (fnumber > 0)
return tupdesc->attrs[fnumber - 1]->atttypid;
else
return (SystemAttributeDefinition(fnumber, true))->atttypid;
}
char *
SPI_getrelname(Relation rel)
{
return pstrdup(RelationGetRelationName(rel));
}
void *
SPI_palloc(Size size)
{
MemoryContext oldcxt = NULL;
void *pointer;
if (_SPI_curid + 1 == _SPI_connected) /* connected */
{
if (_SPI_current != &(_SPI_stack[_SPI_curid + 1]))
elog(FATAL, "SPI: stack corrupted");
oldcxt = MemoryContextSwitchTo(_SPI_current->savedcxt);
}
pointer = palloc(size);
if (oldcxt)
MemoryContextSwitchTo(oldcxt);
return pointer;
}
void *
SPI_repalloc(void *pointer, Size size)
{
/* No longer need to worry which context chunk was in... */
return repalloc(pointer, size);
}
void
SPI_pfree(void *pointer)
{
/* No longer need to worry which context chunk was in... */
pfree(pointer);
}
void
SPI_freetuple(HeapTuple tuple)
{
/* No longer need to worry which context tuple was in... */
heap_freetuple(tuple);
}
void
SPI_freetuptable(SPITupleTable *tuptable)
{
if (tuptable != NULL)
MemoryContextDelete(tuptable->tuptabcxt);
}
/*
* SPI_cursor_open()
*
* Open a prepared SPI plan as a portal
*/
Portal
SPI_cursor_open(char *name, void *plan, Datum *Values, char *Nulls)
{
static int unnamed_portal_count = 0;
_SPI_plan *spiplan = (_SPI_plan *) plan;
List *qtlist = spiplan->qtlist;
List *ptlist = spiplan->ptlist;
Query *queryTree;
Plan *planTree;
ParamListInfo paramLI;
QueryDesc *queryDesc;
MemoryContext oldcontext;
Portal portal;
char portalname[64];
int k;
/* Ensure that the plan contains only one regular SELECT query */
if (length(ptlist) != 1 || length(qtlist) != 1)
elog(ERROR, "cannot open multi-query plan as cursor");
queryTree = (Query *) lfirst((List *) lfirst(qtlist));
planTree = (Plan *) lfirst(ptlist);
if (queryTree->commandType != CMD_SELECT)
elog(ERROR, "plan in SPI_cursor_open() is not a SELECT");
if (queryTree->isPortal)
elog(ERROR, "plan in SPI_cursor_open() must NOT be a DECLARE already");
else if (queryTree->into != NULL)
elog(ERROR, "plan in SPI_cursor_open() must NOT be a SELECT INTO");
/* Increment CommandCounter to see changes made by now */
CommandCounterIncrement();
/* Reset SPI result */
SPI_processed = 0;
SPI_tuptable = NULL;
_SPI_current->processed = 0;
_SPI_current->tuptable = NULL;
if (name == NULL)
{
/* Make up a portal name if none given */
for (;;)
{
unnamed_portal_count++;
if (unnamed_portal_count < 0)
unnamed_portal_count = 0;
sprintf(portalname, "<unnamed cursor %d>", unnamed_portal_count);
if (GetPortalByName(portalname) == NULL)
break;
}
name = portalname;
}
else
{
/* Ensure the portal doesn't exist already */
portal = GetPortalByName(name);
if (portal != NULL)
elog(ERROR, "cursor \"%s\" already in use", name);
}
/* Create the portal */
portal = CreatePortal(name);
if (portal == NULL)
elog(ERROR, "failed to create portal \"%s\"", name);
/* Switch to portals memory and copy the parsetree and plan to there */
oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
queryTree = copyObject(queryTree);
planTree = copyObject(planTree);
/* Modify the parsetree to be a cursor */
queryTree->isPortal = true;
queryTree->into = makeNode(RangeVar);
queryTree->into->relname = pstrdup(name);
queryTree->isBinary = false;
/* If the plan has parameters, set them up */
if (spiplan->nargs > 0)
{
paramLI = (ParamListInfo) palloc0((spiplan->nargs + 1) *
sizeof(ParamListInfoData));
for (k = 0; k < spiplan->nargs; k++)
{
paramLI[k].kind = PARAM_NUM;
paramLI[k].id = k + 1;
paramLI[k].isnull = (Nulls && Nulls[k] == 'n');
if (paramLI[k].isnull)
{
/* nulls just copy */
paramLI[k].value = Values[k];
}
else
{
/* pass-by-ref values must be copied into portal context */
int16 paramTypLen;
bool paramTypByVal;
get_typlenbyval(spiplan->argtypes[k],
¶mTypLen, ¶mTypByVal);
paramLI[k].value = datumCopy(Values[k],
paramTypByVal, paramTypLen);
}
}
paramLI[k].kind = PARAM_INVALID;
}
else
paramLI = NULL;
/* Create the QueryDesc object */
queryDesc = CreateQueryDesc(queryTree, planTree, SPI, NULL,
paramLI, false);
/* Start the executor */
ExecutorStart(queryDesc);
/* Arrange to shut down the executor if portal is dropped */
PortalSetQuery(portal, queryDesc, PortalCleanup);
/* Switch back to the callers memory context */
MemoryContextSwitchTo(oldcontext);
/* Return the created portal */
return portal;
}
/*
* SPI_cursor_find()
*
* Find the portal of an existing open cursor
*/
Portal
SPI_cursor_find(char *name)
{
return GetPortalByName(name);
}
/*
* SPI_cursor_fetch()
*
* Fetch rows in a cursor
*/
void
SPI_cursor_fetch(Portal portal, bool forward, int count)
{
_SPI_cursor_operation(portal, forward, count, SPI);
}
/*
* SPI_cursor_move()
*
* Move in a cursor
*/
void
SPI_cursor_move(Portal portal, bool forward, int count)
{
_SPI_cursor_operation(portal, forward, count, None);
}
/*
* SPI_cursor_close()
*
* Close a cursor
*/
void
SPI_cursor_close(Portal portal)
{
if (!PortalIsValid(portal))
elog(ERROR, "invalid portal in SPI cursor operation");
PortalDrop(portal);
}
/* =================== private functions =================== */
/*
* spi_printtup
* store tuple retrieved by Executor into SPITupleTable
* of current SPI procedure
*
*/
void
spi_printtup(HeapTuple tuple, TupleDesc tupdesc, DestReceiver *self)
{
SPITupleTable *tuptable;
MemoryContext oldcxt;
MemoryContext tuptabcxt;
/*
* When called by Executor _SPI_curid expected to be equal to
* _SPI_connected
*/
if (_SPI_curid != _SPI_connected || _SPI_connected < 0)
elog(FATAL, "SPI: improper call to spi_printtup");
if (_SPI_current != &(_SPI_stack[_SPI_curid]))
elog(FATAL, "SPI: stack corrupted in spi_printtup");
oldcxt = _SPI_procmem(); /* switch to procedure memory context */
tuptable = _SPI_current->tuptable;
if (tuptable == NULL)
{
tuptabcxt = AllocSetContextCreate(CurrentMemoryContext,
"SPI TupTable",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
MemoryContextSwitchTo(tuptabcxt);
_SPI_current->tuptable = tuptable = (SPITupleTable *)
palloc(sizeof(SPITupleTable));
tuptable->tuptabcxt = tuptabcxt;
tuptable->alloced = tuptable->free = 128;
tuptable->vals = (HeapTuple *) palloc(tuptable->alloced * sizeof(HeapTuple));
tuptable->tupdesc = CreateTupleDescCopy(tupdesc);
}
else
{
MemoryContextSwitchTo(tuptable->tuptabcxt);
if (tuptable->free == 0)
{
tuptable->free = 256;
tuptable->alloced += tuptable->free;
tuptable->vals = (HeapTuple *) repalloc(tuptable->vals,
tuptable->alloced * sizeof(HeapTuple));
}
}
tuptable->vals[tuptable->alloced - tuptable->free] = heap_copytuple(tuple);
(tuptable->free)--;
MemoryContextSwitchTo(oldcxt);
return;
}
/*
* Static functions
*/
/*
* Plan and optionally execute a querystring.
*
* If plan != NULL, just prepare plan tree, else execute immediately.
*/
static int
_SPI_execute(char *src, int tcount, _SPI_plan *plan)
{
StringInfoData stri;
List *raw_parsetree_list;
List *query_list_list;
List *plan_list;
List *list_item;
int nargs = 0;
Oid *argtypes = NULL;
int res = 0;
if (plan)
{
nargs = plan->nargs;
argtypes = plan->argtypes;
}
/* Increment CommandCounter to see changes made by now */
CommandCounterIncrement();
/* Reset state (only needed in case string is empty) */
SPI_processed = 0;
SPI_lastoid = InvalidOid;
SPI_tuptable = NULL;
_SPI_current->tuptable = NULL;
/*
* Parse the request string into a list of raw parse trees.
*/
initStringInfo(&stri);
appendStringInfo(&stri, "%s", src);
raw_parsetree_list = pg_parse_query(&stri, argtypes, nargs);
/*
* Do parse analysis and rule rewrite for each raw parsetree.
*
* We save the querytrees from each raw parsetree as a separate
* sublist. This allows _SPI_execute_plan() to know where the
* boundaries between original queries fall.
*/
query_list_list = NIL;
plan_list = NIL;
foreach(list_item, raw_parsetree_list)
{
Node *parsetree = (Node *) lfirst(list_item);
CmdType origCmdType;
bool foundOriginalQuery = false;
List *query_list;
List *query_list_item;
switch (nodeTag(parsetree))
{
case T_InsertStmt:
origCmdType = CMD_INSERT;
break;
case T_DeleteStmt:
origCmdType = CMD_DELETE;
break;
case T_UpdateStmt:
origCmdType = CMD_UPDATE;
break;
case T_SelectStmt:
origCmdType = CMD_SELECT;
break;
default:
/* Otherwise, never match commandType */
origCmdType = CMD_UNKNOWN;
break;
}
if (plan)
plan->origCmdType = origCmdType;
query_list = pg_analyze_and_rewrite(parsetree);
query_list_list = lappend(query_list_list, query_list);
/* Reset state for each original parsetree */
SPI_processed = 0;
SPI_lastoid = InvalidOid;
SPI_tuptable = NULL;
_SPI_current->tuptable = NULL;
foreach(query_list_item, query_list)
{
Query *queryTree = (Query *) lfirst(query_list_item);
Plan *planTree;
bool canSetResult;
QueryDesc *qdesc;
planTree = pg_plan_query(queryTree);
plan_list = lappend(plan_list, planTree);
/*
* This query can set the SPI result if it is the original
* query, or if it is an INSTEAD query of the same kind as the
* original and we haven't yet seen the original query.
*/
if (queryTree->querySource == QSRC_ORIGINAL)
{
canSetResult = true;
foundOriginalQuery = true;
}
else if (!foundOriginalQuery &&
queryTree->commandType == origCmdType &&
(queryTree->querySource == QSRC_INSTEAD_RULE ||
queryTree->querySource == QSRC_QUAL_INSTEAD_RULE))
canSetResult = true;
else
canSetResult = false;
if (queryTree->commandType == CMD_UTILITY)
{
if (IsA(queryTree->utilityStmt, CopyStmt))
{
CopyStmt *stmt = (CopyStmt *) queryTree->utilityStmt;
if (stmt->filename == NULL)
return SPI_ERROR_COPY;
}
else if (IsA(queryTree->utilityStmt, ClosePortalStmt) ||
IsA(queryTree->utilityStmt, FetchStmt))
return SPI_ERROR_CURSOR;
else if (IsA(queryTree->utilityStmt, TransactionStmt))
return SPI_ERROR_TRANSACTION;
res = SPI_OK_UTILITY;
if (plan == NULL)
{
ProcessUtility(queryTree->utilityStmt, None, NULL);
CommandCounterIncrement();
}
}
else if (plan == NULL)
{
qdesc = CreateQueryDesc(queryTree, planTree,
canSetResult ? SPI : None,
NULL, NULL, false);
res = _SPI_pquery(qdesc, true, canSetResult ? tcount : 0);
if (res < 0)
return res;
CommandCounterIncrement();
}
else
{
qdesc = CreateQueryDesc(queryTree, planTree,
canSetResult ? SPI : None,
NULL, NULL, false);
res = _SPI_pquery(qdesc, false, 0);
if (res < 0)
return res;
}
}
}
if (plan)
{
plan->qtlist = query_list_list;
plan->ptlist = plan_list;
}
return res;
}
static int
_SPI_execute_plan(_SPI_plan *plan, Datum *Values, char *Nulls, int tcount)
{
List *query_list_list = plan->qtlist;
List *plan_list = plan->ptlist;
List *query_list_list_item;
int nargs = plan->nargs;
int res = 0;
/* Increment CommandCounter to see changes made by now */
CommandCounterIncrement();
/* Reset state (only needed in case string is empty) */
SPI_processed = 0;
SPI_lastoid = InvalidOid;
SPI_tuptable = NULL;
_SPI_current->tuptable = NULL;
foreach(query_list_list_item, query_list_list)
{
List *query_list = lfirst(query_list_list_item);
List *query_list_item;
bool foundOriginalQuery = false;
/* Reset state for each original parsetree */
SPI_processed = 0;
SPI_lastoid = InvalidOid;
SPI_tuptable = NULL;
_SPI_current->tuptable = NULL;
foreach(query_list_item, query_list)
{
Query *queryTree = (Query *) lfirst(query_list_item);
Plan *planTree;
bool canSetResult;
QueryDesc *qdesc;
planTree = lfirst(plan_list);
plan_list = lnext(plan_list);
/*
* This query can set the SPI result if it is the original
* query, or if it is an INSTEAD query of the same kind as the
* original and we haven't yet seen the original query.
*/
if (queryTree->querySource == QSRC_ORIGINAL)
{
canSetResult = true;
foundOriginalQuery = true;
}
else if (!foundOriginalQuery &&
queryTree->commandType == plan->origCmdType &&
(queryTree->querySource == QSRC_INSTEAD_RULE ||
queryTree->querySource == QSRC_QUAL_INSTEAD_RULE))
canSetResult = true;
else
canSetResult = false;
if (queryTree->commandType == CMD_UTILITY)
{
res = SPI_OK_UTILITY;
ProcessUtility(queryTree->utilityStmt, None, NULL);
CommandCounterIncrement();
}
else
{
ParamListInfo paramLI;
if (nargs > 0)
{
int k;
paramLI = (ParamListInfo)
palloc0((nargs + 1) * sizeof(ParamListInfoData));
for (k = 0; k < plan->nargs; k++)
{
paramLI[k].kind = PARAM_NUM;
paramLI[k].id = k + 1;
paramLI[k].isnull = (Nulls && Nulls[k] == 'n');
paramLI[k].value = Values[k];
}
paramLI[k].kind = PARAM_INVALID;
}
else
paramLI = NULL;
qdesc = CreateQueryDesc(queryTree, planTree,
canSetResult ? SPI : None,
NULL, paramLI, false);
res = _SPI_pquery(qdesc, true, canSetResult ? tcount : 0);
if (res < 0)
return res;
CommandCounterIncrement();
}
}
}
return res;
}
static int
_SPI_pquery(QueryDesc *queryDesc, bool runit, int tcount)
{
Query *parseTree = queryDesc->parsetree;
int operation = queryDesc->operation;
CommandDest dest = queryDesc->dest;
bool isRetrieveIntoPortal = false;
bool isRetrieveIntoRelation = false;
char *intoName = NULL;
int res;
Oid save_lastoid;
switch (operation)
{
case CMD_SELECT:
res = SPI_OK_SELECT;
if (parseTree->isPortal)
{
isRetrieveIntoPortal = true;
intoName = parseTree->into->relname;
parseTree->isBinary = false; /* */
return SPI_ERROR_CURSOR;
}
else if (parseTree->into != NULL) /* select into table */
{
res = SPI_OK_SELINTO;
isRetrieveIntoRelation = true;
queryDesc->dest = None; /* */
}
break;
case CMD_INSERT:
res = SPI_OK_INSERT;
break;
case CMD_DELETE:
res = SPI_OK_DELETE;
break;
case CMD_UPDATE:
res = SPI_OK_UPDATE;
break;
default:
return SPI_ERROR_OPUNKNOWN;
}
if (!runit) /* plan preparation, don't execute */
return res;
#ifdef SPI_EXECUTOR_STATS
if (ShowExecutorStats)
ResetUsage();
#endif
ExecutorStart(queryDesc);
/*
* Don't work currently --- need to rearrange callers so that we
* prepare the portal before doing ExecutorStart() etc. See
* pquery.c for the correct order of operations.
*/
if (isRetrieveIntoPortal)
elog(FATAL, "SPI_select: retrieve into portal not implemented");
ExecutorRun(queryDesc, ForwardScanDirection, (long) tcount);
_SPI_current->processed = queryDesc->estate->es_processed;
save_lastoid = queryDesc->estate->es_lastoid;
if (operation == CMD_SELECT && queryDesc->dest == SPI)
{
if (_SPI_checktuples())
elog(FATAL, "SPI_select: # of processed tuples check failed");
}
if (dest == SPI)
{
SPI_processed = _SPI_current->processed;
SPI_lastoid = save_lastoid;
SPI_tuptable = _SPI_current->tuptable;
}
ExecutorEnd(queryDesc);
FreeQueryDesc(queryDesc);
#ifdef SPI_EXECUTOR_STATS
if (ShowExecutorStats)
ShowUsage("SPI EXECUTOR STATS");
#endif
return res;
}
/*
* _SPI_cursor_operation()
*
* Do a FETCH or MOVE in a cursor
*/
static void
_SPI_cursor_operation(Portal portal, bool forward, int count,
CommandDest dest)
{
QueryDesc *querydesc;
EState *estate;
MemoryContext oldcontext;
ScanDirection direction;
CommandDest olddest;
/* Check that the portal is valid */
if (!PortalIsValid(portal))
elog(ERROR, "invalid portal in SPI cursor operation");
/* Push the SPI stack */
_SPI_begin_call(true);
/* Reset the SPI result */
SPI_processed = 0;
SPI_tuptable = NULL;
_SPI_current->processed = 0;
_SPI_current->tuptable = NULL;
/* Switch to the portals memory context */
oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
querydesc = PortalGetQueryDesc(portal);
estate = querydesc->estate;
/* Save the queries command destination and set it to SPI (for fetch) */
/* or None (for move) */
olddest = querydesc->dest;
querydesc->dest = dest;
/* Run the executor like PerformPortalFetch and remember states */
if (forward)
{
if (portal->atEnd)
direction = NoMovementScanDirection;
else
direction = ForwardScanDirection;
ExecutorRun(querydesc, direction, (long) count);
if (estate->es_processed > 0)
portal->atStart = false; /* OK to back up now */
if (count <= 0 || (int) estate->es_processed < count)
portal->atEnd = true; /* we retrieved 'em all */
}
else
{
if (portal->atStart)
direction = NoMovementScanDirection;
else
direction = BackwardScanDirection;
ExecutorRun(querydesc, direction, (long) count);
if (estate->es_processed > 0)
portal->atEnd = false; /* OK to go forward now */
if (count <= 0 || (int) estate->es_processed < count)
portal->atStart = true; /* we retrieved 'em all */
}
_SPI_current->processed = estate->es_processed;
/* Restore the old command destination and switch back to callers */
/* memory context */
querydesc->dest = olddest;
MemoryContextSwitchTo(oldcontext);
if (dest == SPI && _SPI_checktuples())
elog(FATAL, "SPI_fetch: # of processed tuples check failed");
/* Put the result into place for access by caller */
SPI_processed = _SPI_current->processed;
SPI_tuptable = _SPI_current->tuptable;
/* Pop the SPI stack */
_SPI_end_call(true);
}
static MemoryContext
_SPI_execmem()
{
return MemoryContextSwitchTo(_SPI_current->execCxt);
}
static MemoryContext
_SPI_procmem()
{
return MemoryContextSwitchTo(_SPI_current->procCxt);
}
/*
* _SPI_begin_call
*
*/
static int
_SPI_begin_call(bool execmem)
{
if (_SPI_curid + 1 != _SPI_connected)
return SPI_ERROR_UNCONNECTED;
_SPI_curid++;
if (_SPI_current != &(_SPI_stack[_SPI_curid]))
elog(FATAL, "SPI: stack corrupted");
if (execmem) /* switch to the Executor memory context */
_SPI_execmem();
return 0;
}
static int
_SPI_end_call(bool procmem)
{
/*
* We're returning to procedure where _SPI_curid == _SPI_connected - 1
*/
_SPI_curid--;
if (procmem) /* switch to the procedure memory context */
{
_SPI_procmem();
/* and free Executor memory */
MemoryContextResetAndDeleteChildren(_SPI_current->execCxt);
}
return 0;
}
static bool
_SPI_checktuples(void)
{
uint32 processed = _SPI_current->processed;
SPITupleTable *tuptable = _SPI_current->tuptable;
bool failed = false;
if (processed == 0)
{
if (tuptable != NULL)
failed = true;
}
else
{
/* some tuples were processed */
if (tuptable == NULL) /* spi_printtup was not called */
failed = true;
else if (processed != (tuptable->alloced - tuptable->free))
failed = true;
}
return failed;
}
static _SPI_plan *
_SPI_copy_plan(_SPI_plan *plan, int location)
{
_SPI_plan *newplan;
MemoryContext oldcxt;
MemoryContext plancxt;
MemoryContext parentcxt;
/* Determine correct parent for the plan's memory context */
if (location == _SPI_CPLAN_PROCXT)
parentcxt = _SPI_current->procCxt;
else if (location == _SPI_CPLAN_TOPCXT)
parentcxt = TopMemoryContext;
else /* (this case not currently used) */
parentcxt = CurrentMemoryContext;
/*
* Create a memory context for the plan. We don't expect the plan to
* be very large, so use smaller-than-default alloc parameters.
*/
plancxt = AllocSetContextCreate(parentcxt,
"SPI Plan",
ALLOCSET_SMALL_MINSIZE,
ALLOCSET_SMALL_INITSIZE,
ALLOCSET_SMALL_MAXSIZE);
oldcxt = MemoryContextSwitchTo(plancxt);
/* Copy the SPI plan into its own context */
newplan = (_SPI_plan *) palloc(sizeof(_SPI_plan));
newplan->plancxt = plancxt;
newplan->qtlist = (List *) copyObject(plan->qtlist);
newplan->ptlist = (List *) copyObject(plan->ptlist);
newplan->nargs = plan->nargs;
if (plan->nargs > 0)
{
newplan->argtypes = (Oid *) palloc(plan->nargs * sizeof(Oid));
memcpy(newplan->argtypes, plan->argtypes, plan->nargs * sizeof(Oid));
}
else
newplan->argtypes = NULL;
newplan->origCmdType = plan->origCmdType;
MemoryContextSwitchTo(oldcxt);
return newplan;
}