PostgreSQL Source Code  git master
functions.h File Reference
#include "nodes/execnodes.h"
#include "tcop/dest.h"
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Typedefs

typedef struct SQLFunctionParseInfoSQLFunctionParseInfoPtr
 

Functions

Datum fmgr_sql (PG_FUNCTION_ARGS)
 
SQLFunctionParseInfoPtr prepare_sql_fn_parse_info (HeapTuple procedureTuple, Node *call_expr, Oid inputCollation)
 
void sql_fn_parser_setup (struct ParseState *pstate, SQLFunctionParseInfoPtr pinfo)
 
void check_sql_fn_statements (List *queryTreeList)
 
bool check_sql_fn_retval (Oid func_id, Oid rettype, List *queryTreeList, bool *modifyTargetList, JunkFilter **junkFilter)
 
DestReceiverCreateSQLFunctionDestReceiver (void)
 

Typedef Documentation

◆ SQLFunctionParseInfoPtr

Definition at line 21 of file functions.h.

Function Documentation

◆ check_sql_fn_retval()

bool check_sql_fn_retval ( Oid  func_id,
Oid  rettype,
List queryTreeList,
bool modifyTargetList,
JunkFilter **  junkFilter 
)

Definition at line 1586 of file functions.c.

References Assert, AssertArg, Query::canSetTag, CMD_DELETE, CMD_INSERT, CMD_SELECT, CMD_UPDATE, COERCE_IMPLICIT_CAST, Query::commandType, CreateTupleDescCopy(), ereport, errcode(), errdetail(), errmsg(), ERROR, ExecCleanTargetListLength(), ExecInitJunkFilter(), ExecInitJunkFilterConversion(), TargetEntry::expr, exprType(), format_type_be(), get_func_result_type(), get_typcollation(), get_typtype(), InvalidOid, IsBinaryCoercible(), lappend(), lfirst, lfirst_node, linitial, list_concat(), makeConst(), makeRelabelType(), makeTargetEntry(), tupleDesc::natts, NIL, parse(), TargetEntry::resjunk, TargetEntry::resno, TargetEntry::ressortgroupref, Query::returningList, Query::setOperations, Query::targetList, TupleDescAttr, and TYPEFUNC_COMPOSITE.

Referenced by fmgr_sql_validator(), init_sql_fcache(), inline_function(), and inline_set_returning_function().

1589 {
1590  Query *parse;
1591  List **tlist_ptr;
1592  List *tlist;
1593  int tlistlen;
1594  char fn_typtype;
1595  Oid restype;
1596  ListCell *lc;
1597 
1598  AssertArg(!IsPolymorphicType(rettype));
1599 
1600  if (modifyTargetList)
1601  *modifyTargetList = false; /* initialize for no change */
1602  if (junkFilter)
1603  *junkFilter = NULL; /* initialize in case of VOID result */
1604 
1605  /*
1606  * If it's declared to return VOID, we don't care what's in the function.
1607  * (This takes care of the procedure case, as well.)
1608  */
1609  if (rettype == VOIDOID)
1610  return false;
1611 
1612  /*
1613  * Find the last canSetTag query in the list. This isn't necessarily the
1614  * last parsetree, because rule rewriting can insert queries after what
1615  * the user wrote.
1616  */
1617  parse = NULL;
1618  foreach(lc, queryTreeList)
1619  {
1620  Query *q = lfirst_node(Query, lc);
1621 
1622  if (q->canSetTag)
1623  parse = q;
1624  }
1625 
1626  /*
1627  * If it's a plain SELECT, it returns whatever the targetlist says.
1628  * Otherwise, if it's INSERT/UPDATE/DELETE with RETURNING, it returns
1629  * that. Otherwise, the function return type must be VOID.
1630  *
1631  * Note: eventually replace this test with QueryReturnsTuples? We'd need
1632  * a more general method of determining the output type, though. Also, it
1633  * seems too dangerous to consider FETCH or EXECUTE as returning a
1634  * determinable rowtype, since they depend on relatively short-lived
1635  * entities.
1636  */
1637  if (parse &&
1638  parse->commandType == CMD_SELECT)
1639  {
1640  tlist_ptr = &parse->targetList;
1641  tlist = parse->targetList;
1642  }
1643  else if (parse &&
1644  (parse->commandType == CMD_INSERT ||
1645  parse->commandType == CMD_UPDATE ||
1646  parse->commandType == CMD_DELETE) &&
1647  parse->returningList)
1648  {
1649  tlist_ptr = &parse->returningList;
1650  tlist = parse->returningList;
1651  }
1652  else
1653  {
1654  /* Empty function body, or last statement is a utility command */
1655  ereport(ERROR,
1656  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1657  errmsg("return type mismatch in function declared to return %s",
1658  format_type_be(rettype)),
1659  errdetail("Function's final statement must be SELECT or INSERT/UPDATE/DELETE RETURNING.")));
1660  return false; /* keep compiler quiet */
1661  }
1662 
1663  /*
1664  * OK, check that the targetlist returns something matching the declared
1665  * type.
1666  */
1667 
1668  /*
1669  * Count the non-junk entries in the result targetlist.
1670  */
1671  tlistlen = ExecCleanTargetListLength(tlist);
1672 
1673  fn_typtype = get_typtype(rettype);
1674 
1675  if (fn_typtype == TYPTYPE_BASE ||
1676  fn_typtype == TYPTYPE_DOMAIN ||
1677  fn_typtype == TYPTYPE_ENUM ||
1678  fn_typtype == TYPTYPE_RANGE)
1679  {
1680  /*
1681  * For scalar-type returns, the target list must have exactly one
1682  * non-junk entry, and its type must agree with what the user
1683  * declared; except we allow binary-compatible types too.
1684  */
1685  TargetEntry *tle;
1686 
1687  if (tlistlen != 1)
1688  ereport(ERROR,
1689  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1690  errmsg("return type mismatch in function declared to return %s",
1691  format_type_be(rettype)),
1692  errdetail("Final statement must return exactly one column.")));
1693 
1694  /* We assume here that non-junk TLEs must come first in tlists */
1695  tle = (TargetEntry *) linitial(tlist);
1696  Assert(!tle->resjunk);
1697 
1698  restype = exprType((Node *) tle->expr);
1699  if (!IsBinaryCoercible(restype, rettype))
1700  ereport(ERROR,
1701  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1702  errmsg("return type mismatch in function declared to return %s",
1703  format_type_be(rettype)),
1704  errdetail("Actual return type is %s.",
1705  format_type_be(restype))));
1706  if (modifyTargetList && restype != rettype)
1707  {
1708  tle->expr = (Expr *) makeRelabelType(tle->expr,
1709  rettype,
1710  -1,
1711  get_typcollation(rettype),
1713  /* Relabel is dangerous if TLE is a sort/group or setop column */
1714  if (tle->ressortgroupref != 0 || parse->setOperations)
1715  *modifyTargetList = true;
1716  }
1717 
1718  /* Set up junk filter if needed */
1719  if (junkFilter)
1720  *junkFilter = ExecInitJunkFilter(tlist, false, NULL);
1721  }
1722  else if (fn_typtype == TYPTYPE_COMPOSITE || rettype == RECORDOID)
1723  {
1724  /*
1725  * Returns a rowtype.
1726  *
1727  * Note that we will not consider a domain over composite to be a
1728  * "rowtype" return type; it goes through the scalar case above. This
1729  * is because SQL functions don't provide any implicit casting to the
1730  * result type, so there is no way to produce a domain-over-composite
1731  * result except by computing it as an explicit single-column result.
1732  */
1733  TupleDesc tupdesc;
1734  int tupnatts; /* physical number of columns in tuple */
1735  int tuplogcols; /* # of nondeleted columns in tuple */
1736  int colindex; /* physical column index */
1737  List *newtlist; /* new non-junk tlist entries */
1738  List *junkattrs; /* new junk tlist entries */
1739 
1740  /*
1741  * If the target list is of length 1, and the type of the varnode in
1742  * the target list matches the declared return type, this is okay.
1743  * This can happen, for example, where the body of the function is
1744  * 'SELECT func2()', where func2 has the same composite return type as
1745  * the function that's calling it.
1746  *
1747  * XXX Note that if rettype is RECORD, the IsBinaryCoercible check
1748  * will succeed for any composite restype. For the moment we rely on
1749  * runtime type checking to catch any discrepancy, but it'd be nice to
1750  * do better at parse time.
1751  */
1752  if (tlistlen == 1)
1753  {
1754  TargetEntry *tle = (TargetEntry *) linitial(tlist);
1755 
1756  Assert(!tle->resjunk);
1757  restype = exprType((Node *) tle->expr);
1758  if (IsBinaryCoercible(restype, rettype))
1759  {
1760  if (modifyTargetList && restype != rettype)
1761  {
1762  tle->expr = (Expr *) makeRelabelType(tle->expr,
1763  rettype,
1764  -1,
1765  get_typcollation(rettype),
1767  /* Relabel is dangerous if sort/group or setop column */
1768  if (tle->ressortgroupref != 0 || parse->setOperations)
1769  *modifyTargetList = true;
1770  }
1771  /* Set up junk filter if needed */
1772  if (junkFilter)
1773  *junkFilter = ExecInitJunkFilter(tlist, false, NULL);
1774  return false; /* NOT returning whole tuple */
1775  }
1776  }
1777 
1778  /*
1779  * Is the rowtype fixed, or determined only at runtime? (Note we
1780  * cannot see TYPEFUNC_COMPOSITE_DOMAIN here.)
1781  */
1782  if (get_func_result_type(func_id, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
1783  {
1784  /*
1785  * Assume we are returning the whole tuple. Crosschecking against
1786  * what the caller expects will happen at runtime.
1787  */
1788  if (junkFilter)
1789  *junkFilter = ExecInitJunkFilter(tlist, false, NULL);
1790  return true;
1791  }
1792  Assert(tupdesc);
1793 
1794  /*
1795  * Verify that the targetlist matches the return tuple type. We scan
1796  * the non-deleted attributes to ensure that they match the datatypes
1797  * of the non-resjunk columns. For deleted attributes, insert NULL
1798  * result columns if the caller asked for that.
1799  */
1800  tupnatts = tupdesc->natts;
1801  tuplogcols = 0; /* we'll count nondeleted cols as we go */
1802  colindex = 0;
1803  newtlist = NIL; /* these are only used if modifyTargetList */
1804  junkattrs = NIL;
1805 
1806  foreach(lc, tlist)
1807  {
1808  TargetEntry *tle = (TargetEntry *) lfirst(lc);
1809  Form_pg_attribute attr;
1810  Oid tletype;
1811  Oid atttype;
1812 
1813  if (tle->resjunk)
1814  {
1815  if (modifyTargetList)
1816  junkattrs = lappend(junkattrs, tle);
1817  continue;
1818  }
1819 
1820  do
1821  {
1822  colindex++;
1823  if (colindex > tupnatts)
1824  ereport(ERROR,
1825  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1826  errmsg("return type mismatch in function declared to return %s",
1827  format_type_be(rettype)),
1828  errdetail("Final statement returns too many columns.")));
1829  attr = TupleDescAttr(tupdesc, colindex - 1);
1830  if (attr->attisdropped && modifyTargetList)
1831  {
1832  Expr *null_expr;
1833 
1834  /* The type of the null we insert isn't important */
1835  null_expr = (Expr *) makeConst(INT4OID,
1836  -1,
1837  InvalidOid,
1838  sizeof(int32),
1839  (Datum) 0,
1840  true, /* isnull */
1841  true /* byval */ );
1842  newtlist = lappend(newtlist,
1843  makeTargetEntry(null_expr,
1844  colindex,
1845  NULL,
1846  false));
1847  /* NULL insertion is dangerous in a setop */
1848  if (parse->setOperations)
1849  *modifyTargetList = true;
1850  }
1851  } while (attr->attisdropped);
1852  tuplogcols++;
1853 
1854  tletype = exprType((Node *) tle->expr);
1855  atttype = attr->atttypid;
1856  if (!IsBinaryCoercible(tletype, atttype))
1857  ereport(ERROR,
1858  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1859  errmsg("return type mismatch in function declared to return %s",
1860  format_type_be(rettype)),
1861  errdetail("Final statement returns %s instead of %s at column %d.",
1862  format_type_be(tletype),
1863  format_type_be(atttype),
1864  tuplogcols)));
1865  if (modifyTargetList)
1866  {
1867  if (tletype != atttype)
1868  {
1869  tle->expr = (Expr *) makeRelabelType(tle->expr,
1870  atttype,
1871  -1,
1872  get_typcollation(atttype),
1874  /* Relabel is dangerous if sort/group or setop column */
1875  if (tle->ressortgroupref != 0 || parse->setOperations)
1876  *modifyTargetList = true;
1877  }
1878  tle->resno = colindex;
1879  newtlist = lappend(newtlist, tle);
1880  }
1881  }
1882 
1883  /* remaining columns in tupdesc had better all be dropped */
1884  for (colindex++; colindex <= tupnatts; colindex++)
1885  {
1886  if (!TupleDescAttr(tupdesc, colindex - 1)->attisdropped)
1887  ereport(ERROR,
1888  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1889  errmsg("return type mismatch in function declared to return %s",
1890  format_type_be(rettype)),
1891  errdetail("Final statement returns too few columns.")));
1892  if (modifyTargetList)
1893  {
1894  Expr *null_expr;
1895 
1896  /* The type of the null we insert isn't important */
1897  null_expr = (Expr *) makeConst(INT4OID,
1898  -1,
1899  InvalidOid,
1900  sizeof(int32),
1901  (Datum) 0,
1902  true, /* isnull */
1903  true /* byval */ );
1904  newtlist = lappend(newtlist,
1905  makeTargetEntry(null_expr,
1906  colindex,
1907  NULL,
1908  false));
1909  /* NULL insertion is dangerous in a setop */
1910  if (parse->setOperations)
1911  *modifyTargetList = true;
1912  }
1913  }
1914 
1915  if (modifyTargetList)
1916  {
1917  /* ensure resjunk columns are numbered correctly */
1918  foreach(lc, junkattrs)
1919  {
1920  TargetEntry *tle = (TargetEntry *) lfirst(lc);
1921 
1922  tle->resno = colindex++;
1923  }
1924  /* replace the tlist with the modified one */
1925  *tlist_ptr = list_concat(newtlist, junkattrs);
1926  }
1927 
1928  /* Set up junk filter if needed */
1929  if (junkFilter)
1930  *junkFilter = ExecInitJunkFilterConversion(tlist,
1931  CreateTupleDescCopy(tupdesc),
1932  NULL);
1933 
1934  /* Report that we are returning entire tuple result */
1935  return true;
1936  }
1937  else
1938  ereport(ERROR,
1939  (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1940  errmsg("return type %s is not supported for SQL functions",
1941  format_type_be(rettype))));
1942 
1943  return false;
1944 }
#define NIL
Definition: pg_list.h:69
TupleDesc CreateTupleDescCopy(TupleDesc tupdesc)
Definition: tupdesc.c:112
#define TupleDescAttr(tupdesc, i)
Definition: tupdesc.h:93
JunkFilter * ExecInitJunkFilterConversion(List *targetList, TupleDesc cleanTupType, TupleTableSlot *slot)
Definition: execJunk.c:136
Definition: nodes.h:517
int errcode(int sqlerrcode)
Definition: elog.c:575
char get_typtype(Oid typid)
Definition: lsyscache.c:2383
char * format_type_be(Oid type_oid)
Definition: format_type.c:328
List * list_concat(List *list1, List *list2)
Definition: list.c:321
unsigned int Oid
Definition: postgres_ext.h:31
Const * makeConst(Oid consttype, int32 consttypmod, Oid constcollid, int constlen, Datum constvalue, bool constisnull, bool constbyval)
Definition: makefuncs.c:298
int natts
Definition: tupdesc.h:82
signed int int32
Definition: c.h:313
List * targetList
Definition: parsenodes.h:140
bool resjunk
Definition: primnodes.h:1383
#define linitial(l)
Definition: pg_list.h:111
#define ERROR
Definition: elog.h:43
#define lfirst_node(type, lc)
Definition: pg_list.h:109
RelabelType * makeRelabelType(Expr *arg, Oid rtype, int32 rtypmod, Oid rcollid, CoercionForm rformat)
Definition: makefuncs.c:401
JunkFilter * ExecInitJunkFilter(List *targetList, bool hasoid, TupleTableSlot *slot)
Definition: execJunk.c:61
int errdetail(const char *fmt,...)
Definition: elog.c:873
AttrNumber resno
Definition: primnodes.h:1377
FormData_pg_attribute * Form_pg_attribute
Definition: pg_attribute.h:197
List * returningList
Definition: parsenodes.h:146
#define ereport(elevel, rest)
Definition: elog.h:122
TargetEntry * makeTargetEntry(Expr *expr, AttrNumber resno, char *resname, bool resjunk)
Definition: makefuncs.c:237
#define AssertArg(condition)
Definition: c.h:701
bool IsBinaryCoercible(Oid srctype, Oid targettype)
List * lappend(List *list, void *datum)
Definition: list.c:128
int ExecCleanTargetListLength(List *targetlist)
Definition: execUtils.c:1049
TypeFuncClass get_func_result_type(Oid functionId, Oid *resultTypeId, TupleDesc *resultTupleDesc)
Definition: funcapi.c:272
uintptr_t Datum
Definition: postgres.h:365
#define InvalidOid
Definition: postgres_ext.h:36
Oid get_typcollation(Oid typid)
Definition: lsyscache.c:2799
CmdType commandType
Definition: parsenodes.h:112
#define Assert(condition)
Definition: c.h:699
#define lfirst(lc)
Definition: pg_list.h:106
Expr * expr
Definition: primnodes.h:1376
bool canSetTag
Definition: parsenodes.h:118
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:42
Node * setOperations
Definition: parsenodes.h:165
int errmsg(const char *fmt,...)
Definition: elog.c:797
Index ressortgroupref
Definition: primnodes.h:1379
Definition: pg_list.h:45
static struct subre * parse(struct vars *, int, int, struct state *, struct state *)
Definition: regcomp.c:649

◆ check_sql_fn_statements()

void check_sql_fn_statements ( List queryTreeList)

Definition at line 1500 of file functions.c.

References castNode, CMD_UTILITY, Query::commandType, elog, ereport, errcode(), errmsg(), ERROR, CallStmt::funcexpr, FuncExpr::funcid, get_func_arg_info(), HeapTupleIsValid, i, IsA, lfirst_node, ObjectIdGetDatum, PROCOID, ReleaseSysCache(), SearchSysCache1(), execution_state::stmt, and Query::utilityStmt.

Referenced by fmgr_sql_validator(), and init_sql_fcache().

1501 {
1502  ListCell *lc;
1503 
1504  foreach(lc, queryTreeList)
1505  {
1506  Query *query = lfirst_node(Query, lc);
1507 
1508  /*
1509  * Disallow procedures with output arguments. The current
1510  * implementation would just throw the output values away, unless the
1511  * statement is the last one. Per SQL standard, we should assign the
1512  * output values by name. By disallowing this here, we preserve an
1513  * opportunity for future improvement.
1514  */
1515  if (query->commandType == CMD_UTILITY &&
1516  IsA(query->utilityStmt, CallStmt))
1517  {
1518  CallStmt *stmt = castNode(CallStmt, query->utilityStmt);
1519  HeapTuple tuple;
1520  int numargs;
1521  Oid *argtypes;
1522  char **argnames;
1523  char *argmodes;
1524  int i;
1525 
1527  if (!HeapTupleIsValid(tuple))
1528  elog(ERROR, "cache lookup failed for function %u", stmt->funcexpr->funcid);
1529  numargs = get_func_arg_info(tuple, &argtypes, &argnames, &argmodes);
1530  ReleaseSysCache(tuple);
1531 
1532  for (i = 0; i < numargs; i++)
1533  {
1534  if (argmodes && (argmodes[i] == PROARGMODE_INOUT || argmodes[i] == PROARGMODE_OUT))
1535  ereport(ERROR,
1536  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1537  errmsg("calling procedures with output arguments is not supported in SQL functions")));
1538  }
1539  }
1540  }
1541 }
#define IsA(nodeptr, _type_)
Definition: nodes.h:568
FuncExpr * funcexpr
Definition: parsenodes.h:2827
#define castNode(_type_, nodeptr)
Definition: nodes.h:586
int get_func_arg_info(HeapTuple procTup, Oid **p_argtypes, char ***p_argnames, char **p_argmodes)
Definition: funcapi.c:846
int errcode(int sqlerrcode)
Definition: elog.c:575
unsigned int Oid
Definition: postgres_ext.h:31
Node * utilityStmt
Definition: parsenodes.h:120
Oid funcid
Definition: primnodes.h:450
#define ObjectIdGetDatum(X)
Definition: postgres.h:490
#define ERROR
Definition: elog.h:43
#define lfirst_node(type, lc)
Definition: pg_list.h:109
#define ereport(elevel, rest)
Definition: elog.h:122
HeapTuple SearchSysCache1(int cacheId, Datum key1)
Definition: syscache.c:1112
void ReleaseSysCache(HeapTuple tuple)
Definition: syscache.c:1160
CmdType commandType
Definition: parsenodes.h:112
#define HeapTupleIsValid(tuple)
Definition: htup.h:78
int errmsg(const char *fmt,...)
Definition: elog.c:797
int i
#define elog
Definition: elog.h:219

◆ CreateSQLFunctionDestReceiver()

DestReceiver* CreateSQLFunctionDestReceiver ( void  )

Definition at line 1951 of file functions.c.

References DestSQLFunction, palloc0(), sqlfunction_destroy(), sqlfunction_receive(), sqlfunction_shutdown(), and sqlfunction_startup().

Referenced by CreateDestReceiver().

1952 {
1953  DR_sqlfunction *self = (DR_sqlfunction *) palloc0(sizeof(DR_sqlfunction));
1954 
1955  self->pub.receiveSlot = sqlfunction_receive;
1956  self->pub.rStartup = sqlfunction_startup;
1957  self->pub.rShutdown = sqlfunction_shutdown;
1958  self->pub.rDestroy = sqlfunction_destroy;
1959  self->pub.mydest = DestSQLFunction;
1960 
1961  /* private fields will be set by postquel_start */
1962 
1963  return (DestReceiver *) self;
1964 }
static void sqlfunction_destroy(DestReceiver *self)
Definition: functions.c:2005
static void sqlfunction_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
Definition: functions.c:1970
static bool sqlfunction_receive(TupleTableSlot *slot, DestReceiver *self)
Definition: functions.c:1979
void * palloc0(Size size)
Definition: mcxt.c:955
static void sqlfunction_shutdown(DestReceiver *self)
Definition: functions.c:1996

◆ fmgr_sql()

Datum fmgr_sql ( PG_FUNCTION_ARGS  )

Definition at line 995 of file functions.c.

References ReturnSetInfo::allowedModes, ErrorContextCallback::arg, Assert, ErrorContextCallback::callback, CommandCounterIncrement(), CreateTupleDescCopy(), ReturnSetInfo::econtext, elog, ereport, errcode(), errmsg(), ERROR, error_context_stack, ExprEndResult, ExprMultipleResult, F_EXEC_DONE, F_EXEC_START, SQLFunctionCache::fcontext, SQLFunctionCache::func_state, GetTransactionSnapshot(), init_sql_fcache(), IsA, ReturnSetInfo::isDone, JunkFilter::jf_cleanTupType, JunkFilter::jf_resultSlot, SQLFunctionCache::junkFilter, execution_state::lazyEval, SQLFunctionCache::lazyEval, lfirst, lnext, PGPROC::lxid, SQLFunctionCache::lxid, MemoryContextDelete(), MemoryContextSwitchTo(), MyProc, execution_state::next, PG_GET_COLLATION, PointerGetDatum, PopActiveSnapshot(), postquel_end(), postquel_get_single_result(), postquel_getnext(), postquel_start(), postquel_sub_params(), ErrorContextCallback::previous, PushActiveSnapshot(), execution_state::qd, SQLFunctionCache::readonly_func, RegisterExprContextCallback(), SQLFunctionCache::rettype, ReturnSetInfo::returnMode, SQLFunctionCache::returnsSet, ReturnSetInfo::setDesc, ReturnSetInfo::setResult, SFRM_Materialize, SFRM_Materialize_Preferred, SFRM_Materialize_Random, SFRM_ValuePerCall, SQLFunctionCache::shutdown_reg, ShutdownSQLFunction(), QueryDesc::snapshot, sql_exec_error_callback(), execution_state::status, SubTransactionIsActive(), SQLFunctionCache::subxid, SQLFunctionCache::tstore, tuplestore_begin_heap(), tuplestore_clear(), tuplestore_gettupleslot(), UnregisterExprContextCallback(), UpdateActiveSnapshotCommandId(), and work_mem.

Referenced by fmgr_info_cxt_security().

996 {
997  SQLFunctionCachePtr fcache;
998  ErrorContextCallback sqlerrcontext;
999  MemoryContext oldcontext;
1000  bool randomAccess;
1001  bool lazyEvalOK;
1002  bool is_first;
1003  bool pushed_snapshot;
1004  execution_state *es;
1005  TupleTableSlot *slot;
1006  Datum result;
1007  List *eslist;
1008  ListCell *eslc;
1009 
1010  /*
1011  * Setup error traceback support for ereport()
1012  */
1013  sqlerrcontext.callback = sql_exec_error_callback;
1014  sqlerrcontext.arg = fcinfo->flinfo;
1015  sqlerrcontext.previous = error_context_stack;
1016  error_context_stack = &sqlerrcontext;
1017 
1018  /* Check call context */
1019  if (fcinfo->flinfo->fn_retset)
1020  {
1021  ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo;
1022 
1023  /*
1024  * For simplicity, we require callers to support both set eval modes.
1025  * There are cases where we must use one or must use the other, and
1026  * it's not really worthwhile to postpone the check till we know. But
1027  * note we do not require caller to provide an expectedDesc.
1028  */
1029  if (!rsi || !IsA(rsi, ReturnSetInfo) ||
1030  (rsi->allowedModes & SFRM_ValuePerCall) == 0 ||
1031  (rsi->allowedModes & SFRM_Materialize) == 0)
1032  ereport(ERROR,
1033  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1034  errmsg("set-valued function called in context that cannot accept a set")));
1035  randomAccess = rsi->allowedModes & SFRM_Materialize_Random;
1036  lazyEvalOK = !(rsi->allowedModes & SFRM_Materialize_Preferred);
1037  }
1038  else
1039  {
1040  randomAccess = false;
1041  lazyEvalOK = true;
1042  }
1043 
1044  /*
1045  * Initialize fcache (build plans) if first time through; or re-initialize
1046  * if the cache is stale.
1047  */
1048  fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra;
1049 
1050  if (fcache != NULL)
1051  {
1052  if (fcache->lxid != MyProc->lxid ||
1053  !SubTransactionIsActive(fcache->subxid))
1054  {
1055  /* It's stale; unlink and delete */
1056  fcinfo->flinfo->fn_extra = NULL;
1057  MemoryContextDelete(fcache->fcontext);
1058  fcache = NULL;
1059  }
1060  }
1061 
1062  if (fcache == NULL)
1063  {
1064  init_sql_fcache(fcinfo->flinfo, PG_GET_COLLATION(), lazyEvalOK);
1065  fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra;
1066  }
1067 
1068  /*
1069  * Switch to context in which the fcache lives. This ensures that our
1070  * tuplestore etc will have sufficient lifetime. The sub-executor is
1071  * responsible for deleting per-tuple information. (XXX in the case of a
1072  * long-lived FmgrInfo, this policy represents more memory leakage, but
1073  * it's not entirely clear where to keep stuff instead.)
1074  */
1075  oldcontext = MemoryContextSwitchTo(fcache->fcontext);
1076 
1077  /*
1078  * Find first unfinished query in function, and note whether it's the
1079  * first query.
1080  */
1081  eslist = fcache->func_state;
1082  es = NULL;
1083  is_first = true;
1084  foreach(eslc, eslist)
1085  {
1086  es = (execution_state *) lfirst(eslc);
1087 
1088  while (es && es->status == F_EXEC_DONE)
1089  {
1090  is_first = false;
1091  es = es->next;
1092  }
1093 
1094  if (es)
1095  break;
1096  }
1097 
1098  /*
1099  * Convert params to appropriate format if starting a fresh execution. (If
1100  * continuing execution, we can re-use prior params.)
1101  */
1102  if (is_first && es && es->status == F_EXEC_START)
1103  postquel_sub_params(fcache, fcinfo);
1104 
1105  /*
1106  * Build tuplestore to hold results, if we don't have one already. Note
1107  * it's in the query-lifespan context.
1108  */
1109  if (!fcache->tstore)
1110  fcache->tstore = tuplestore_begin_heap(randomAccess, false, work_mem);
1111 
1112  /*
1113  * Execute each command in the function one after another until we either
1114  * run out of commands or get a result row from a lazily-evaluated SELECT.
1115  *
1116  * Notes about snapshot management:
1117  *
1118  * In a read-only function, we just use the surrounding query's snapshot.
1119  *
1120  * In a non-read-only function, we rely on the fact that we'll never
1121  * suspend execution between queries of the function: the only reason to
1122  * suspend execution before completion is if we are returning a row from a
1123  * lazily-evaluated SELECT. So, when first entering this loop, we'll
1124  * either start a new query (and push a fresh snapshot) or re-establish
1125  * the active snapshot from the existing query descriptor. If we need to
1126  * start a new query in a subsequent execution of the loop, either we need
1127  * a fresh snapshot (and pushed_snapshot is false) or the existing
1128  * snapshot is on the active stack and we can just bump its command ID.
1129  */
1130  pushed_snapshot = false;
1131  while (es)
1132  {
1133  bool completed;
1134 
1135  if (es->status == F_EXEC_START)
1136  {
1137  /*
1138  * If not read-only, be sure to advance the command counter for
1139  * each command, so that all work to date in this transaction is
1140  * visible. Take a new snapshot if we don't have one yet,
1141  * otherwise just bump the command ID in the existing snapshot.
1142  */
1143  if (!fcache->readonly_func)
1144  {
1146  if (!pushed_snapshot)
1147  {
1149  pushed_snapshot = true;
1150  }
1151  else
1153  }
1154 
1155  postquel_start(es, fcache);
1156  }
1157  else if (!fcache->readonly_func && !pushed_snapshot)
1158  {
1159  /* Re-establish active snapshot when re-entering function */
1161  pushed_snapshot = true;
1162  }
1163 
1164  completed = postquel_getnext(es, fcache);
1165 
1166  /*
1167  * If we ran the command to completion, we can shut it down now. Any
1168  * row(s) we need to return are safely stashed in the tuplestore, and
1169  * we want to be sure that, for example, AFTER triggers get fired
1170  * before we return anything. Also, if the function doesn't return
1171  * set, we can shut it down anyway because it must be a SELECT and we
1172  * don't care about fetching any more result rows.
1173  */
1174  if (completed || !fcache->returnsSet)
1175  postquel_end(es);
1176 
1177  /*
1178  * Break from loop if we didn't shut down (implying we got a
1179  * lazily-evaluated row). Otherwise we'll press on till the whole
1180  * function is done, relying on the tuplestore to keep hold of the
1181  * data to eventually be returned. This is necessary since an
1182  * INSERT/UPDATE/DELETE RETURNING that sets the result might be
1183  * followed by additional rule-inserted commands, and we want to
1184  * finish doing all those commands before we return anything.
1185  */
1186  if (es->status != F_EXEC_DONE)
1187  break;
1188 
1189  /*
1190  * Advance to next execution_state, which might be in the next list.
1191  */
1192  es = es->next;
1193  while (!es)
1194  {
1195  eslc = lnext(eslc);
1196  if (!eslc)
1197  break; /* end of function */
1198 
1199  es = (execution_state *) lfirst(eslc);
1200 
1201  /*
1202  * Flush the current snapshot so that we will take a new one for
1203  * the new query list. This ensures that new snaps are taken at
1204  * original-query boundaries, matching the behavior of interactive
1205  * execution.
1206  */
1207  if (pushed_snapshot)
1208  {
1210  pushed_snapshot = false;
1211  }
1212  }
1213  }
1214 
1215  /*
1216  * The tuplestore now contains whatever row(s) we are supposed to return.
1217  */
1218  if (fcache->returnsSet)
1219  {
1220  ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo;
1221 
1222  if (es)
1223  {
1224  /*
1225  * If we stopped short of being done, we must have a lazy-eval
1226  * row.
1227  */
1228  Assert(es->lazyEval);
1229  /* Re-use the junkfilter's output slot to fetch back the tuple */
1230  Assert(fcache->junkFilter);
1231  slot = fcache->junkFilter->jf_resultSlot;
1232  if (!tuplestore_gettupleslot(fcache->tstore, true, false, slot))
1233  elog(ERROR, "failed to fetch lazy-eval tuple");
1234  /* Extract the result as a datum, and copy out from the slot */
1235  result = postquel_get_single_result(slot, fcinfo,
1236  fcache, oldcontext);
1237  /* Clear the tuplestore, but keep it for next time */
1238  /* NB: this might delete the slot's content, but we don't care */
1239  tuplestore_clear(fcache->tstore);
1240 
1241  /*
1242  * Let caller know we're not finished.
1243  */
1244  rsi->isDone = ExprMultipleResult;
1245 
1246  /*
1247  * Ensure we will get shut down cleanly if the exprcontext is not
1248  * run to completion.
1249  */
1250  if (!fcache->shutdown_reg)
1251  {
1254  PointerGetDatum(fcache));
1255  fcache->shutdown_reg = true;
1256  }
1257  }
1258  else if (fcache->lazyEval)
1259  {
1260  /*
1261  * We are done with a lazy evaluation. Clean up.
1262  */
1263  tuplestore_clear(fcache->tstore);
1264 
1265  /*
1266  * Let caller know we're finished.
1267  */
1268  rsi->isDone = ExprEndResult;
1269 
1270  fcinfo->isnull = true;
1271  result = (Datum) 0;
1272 
1273  /* Deregister shutdown callback, if we made one */
1274  if (fcache->shutdown_reg)
1275  {
1278  PointerGetDatum(fcache));
1279  fcache->shutdown_reg = false;
1280  }
1281  }
1282  else
1283  {
1284  /*
1285  * We are done with a non-lazy evaluation. Return whatever is in
1286  * the tuplestore. (It is now caller's responsibility to free the
1287  * tuplestore when done.)
1288  */
1290  rsi->setResult = fcache->tstore;
1291  fcache->tstore = NULL;
1292  /* must copy desc because execSRF.c will free it */
1293  if (fcache->junkFilter)
1295 
1296  fcinfo->isnull = true;
1297  result = (Datum) 0;
1298 
1299  /* Deregister shutdown callback, if we made one */
1300  if (fcache->shutdown_reg)
1301  {
1304  PointerGetDatum(fcache));
1305  fcache->shutdown_reg = false;
1306  }
1307  }
1308  }
1309  else
1310  {
1311  /*
1312  * Non-set function. If we got a row, return it; else return NULL.
1313  */
1314  if (fcache->junkFilter)
1315  {
1316  /* Re-use the junkfilter's output slot to fetch back the tuple */
1317  slot = fcache->junkFilter->jf_resultSlot;
1318  if (tuplestore_gettupleslot(fcache->tstore, true, false, slot))
1319  result = postquel_get_single_result(slot, fcinfo,
1320  fcache, oldcontext);
1321  else
1322  {
1323  fcinfo->isnull = true;
1324  result = (Datum) 0;
1325  }
1326  }
1327  else
1328  {
1329  /* Should only get here for VOID functions and procedures */
1330  Assert(fcache->rettype == VOIDOID);
1331  fcinfo->isnull = true;
1332  result = (Datum) 0;
1333  }
1334 
1335  /* Clear the tuplestore, but keep it for next time */
1336  tuplestore_clear(fcache->tstore);
1337  }
1338 
1339  /* Pop snapshot if we have pushed one */
1340  if (pushed_snapshot)
1342 
1343  /*
1344  * If we've gone through every command in the function, we are done. Reset
1345  * the execution states to start over again on next call.
1346  */
1347  if (es == NULL)
1348  {
1349  foreach(eslc, fcache->func_state)
1350  {
1351  es = (execution_state *) lfirst(eslc);
1352  while (es)
1353  {
1354  es->status = F_EXEC_START;
1355  es = es->next;
1356  }
1357  }
1358  }
1359 
1360  error_context_stack = sqlerrcontext.previous;
1361 
1362  MemoryContextSwitchTo(oldcontext);
1363 
1364  return result;
1365 }
bool SubTransactionIsActive(SubTransactionId subxid)
Definition: xact.c:655
TupleDesc CreateTupleDescCopy(TupleDesc tupdesc)
Definition: tupdesc.c:112
void UpdateActiveSnapshotCommandId(void)
Definition: snapmgr.c:781
#define IsA(nodeptr, _type_)
Definition: nodes.h:568
void MemoryContextDelete(MemoryContext context)
Definition: mcxt.c:211
MemoryContext fcontext
Definition: functions.c:121
PGPROC * MyProc
Definition: proc.c:67
void UnregisterExprContextCallback(ExprContext *econtext, ExprContextCallbackFunction function, Datum arg)
Definition: execUtils.c:798
#define PointerGetDatum(X)
Definition: postgres.h:539
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:109
ExecStatus status
Definition: functions.c:66
int errcode(int sqlerrcode)
Definition: elog.c:575
TupleTableSlot * jf_resultSlot
Definition: execnodes.h:364
JunkFilter * junkFilter
Definition: functions.c:111
static void postquel_start(execution_state *es, SQLFunctionCachePtr fcache)
Definition: functions.c:785
void PopActiveSnapshot(void)
Definition: snapmgr.c:812
Tuplestorestate * tstore
Definition: functions.c:109
void(* callback)(void *arg)
Definition: elog.h:239
struct ErrorContextCallback * previous
Definition: elog.h:238
Snapshot GetTransactionSnapshot(void)
Definition: snapmgr.c:304
#define PG_GET_COLLATION()
Definition: fmgr.h:168
Snapshot snapshot
Definition: execdesc.h:39
ErrorContextCallback * error_context_stack
Definition: elog.c:88
#define ERROR
Definition: elog.h:43
static void sql_exec_error_callback(void *arg)
Definition: functions.c:1372
void tuplestore_clear(Tuplestorestate *state)
Definition: tuplestore.c:418
static void postquel_end(execution_state *es)
Definition: functions.c:881
void PushActiveSnapshot(Snapshot snap)
Definition: snapmgr.c:733
List * func_state
Definition: functions.c:119
LocalTransactionId lxid
Definition: functions.c:124
TupleDesc jf_cleanTupType
Definition: execnodes.h:362
static void ShutdownSQLFunction(Datum arg)
Definition: functions.c:1454
#define lnext(lc)
Definition: pg_list.h:105
#define ereport(elevel, rest)
Definition: elog.h:122
Tuplestorestate * tuplestore_begin_heap(bool randomAccess, bool interXact, int maxKBytes)
Definition: tuplestore.c:318
uintptr_t Datum
Definition: postgres.h:365
void CommandCounterIncrement(void)
Definition: xact.c:914
int work_mem
Definition: globals.c:122
QueryDesc * qd
Definition: functions.c:70
int allowedModes
Definition: execnodes.h:297
SetFunctionReturnMode returnMode
Definition: execnodes.h:299
static Datum postquel_get_single_result(TupleTableSlot *slot, FunctionCallInfo fcinfo, SQLFunctionCachePtr fcache, MemoryContext resultcontext)
Definition: functions.c:952
bool tuplestore_gettupleslot(Tuplestorestate *state, bool forward, bool copy, TupleTableSlot *slot)
Definition: tuplestore.c:1078
#define Assert(condition)
Definition: c.h:699
#define lfirst(lc)
Definition: pg_list.h:106
void RegisterExprContextCallback(ExprContext *econtext, ExprContextCallbackFunction function, Datum arg)
Definition: execUtils.c:772
Tuplestorestate * setResult
Definition: execnodes.h:302
ExprContext * econtext
Definition: execnodes.h:295
SQLFunctionCache * SQLFunctionCachePtr
Definition: functions.c:128
TupleDesc setDesc
Definition: execnodes.h:303
int errmsg(const char *fmt,...)
Definition: elog.c:797
#define elog
Definition: elog.h:219
ExprDoneCond isDone
Definition: execnodes.h:300
SubTransactionId subxid
Definition: functions.c:125
struct execution_state * next
Definition: functions.c:65
static bool postquel_getnext(execution_state *es, SQLFunctionCachePtr fcache)
Definition: functions.c:847
Definition: pg_list.h:45
static void postquel_sub_params(SQLFunctionCachePtr fcache, FunctionCallInfo fcinfo)
Definition: functions.c:901
static void init_sql_fcache(FmgrInfo *finfo, Oid collation, bool lazyEvalOK)
Definition: functions.c:594
LocalTransactionId lxid
Definition: proc.h:106

◆ prepare_sql_fn_parse_info()

SQLFunctionParseInfoPtr prepare_sql_fn_parse_info ( HeapTuple  procedureTuple,
Node call_expr,
Oid  inputCollation 
)

Definition at line 184 of file functions.c.

References SQLFunctionParseInfo::argnames, SQLFunctionParseInfo::argtypes, SQLFunctionParseInfo::collation, ereport, errcode(), errmsg(), ERROR, SQLFunctionParseInfo::fname, format_type_be(), get_call_expr_argtype(), get_func_input_arg_names(), GETSTRUCT, InvalidOid, NameStr, SQLFunctionParseInfo::nargs, palloc(), palloc0(), PointerGetDatum, PROCNAMEARGSNSP, pstrdup(), and SysCacheGetAttr().

Referenced by fmgr_sql_validator(), init_sql_fcache(), inline_function(), and inline_set_returning_function().

187 {
189  Form_pg_proc procedureStruct = (Form_pg_proc) GETSTRUCT(procedureTuple);
190  int nargs;
191 
193 
194  /* Function's name (only) can be used to qualify argument names */
195  pinfo->fname = pstrdup(NameStr(procedureStruct->proname));
196 
197  /* Save the function's input collation */
198  pinfo->collation = inputCollation;
199 
200  /*
201  * Copy input argument types from the pg_proc entry, then resolve any
202  * polymorphic types.
203  */
204  pinfo->nargs = nargs = procedureStruct->pronargs;
205  if (nargs > 0)
206  {
207  Oid *argOidVect;
208  int argnum;
209 
210  argOidVect = (Oid *) palloc(nargs * sizeof(Oid));
211  memcpy(argOidVect,
212  procedureStruct->proargtypes.values,
213  nargs * sizeof(Oid));
214 
215  for (argnum = 0; argnum < nargs; argnum++)
216  {
217  Oid argtype = argOidVect[argnum];
218 
219  if (IsPolymorphicType(argtype))
220  {
221  argtype = get_call_expr_argtype(call_expr, argnum);
222  if (argtype == InvalidOid)
223  ereport(ERROR,
224  (errcode(ERRCODE_DATATYPE_MISMATCH),
225  errmsg("could not determine actual type of argument declared %s",
226  format_type_be(argOidVect[argnum]))));
227  argOidVect[argnum] = argtype;
228  }
229  }
230 
231  pinfo->argtypes = argOidVect;
232  }
233 
234  /*
235  * Collect names of arguments, too, if any
236  */
237  if (nargs > 0)
238  {
239  Datum proargnames;
240  Datum proargmodes;
241  int n_arg_names;
242  bool isNull;
243 
244  proargnames = SysCacheGetAttr(PROCNAMEARGSNSP, procedureTuple,
245  Anum_pg_proc_proargnames,
246  &isNull);
247  if (isNull)
248  proargnames = PointerGetDatum(NULL); /* just to be sure */
249 
250  proargmodes = SysCacheGetAttr(PROCNAMEARGSNSP, procedureTuple,
251  Anum_pg_proc_proargmodes,
252  &isNull);
253  if (isNull)
254  proargmodes = PointerGetDatum(NULL); /* just to be sure */
255 
256  n_arg_names = get_func_input_arg_names(proargnames, proargmodes,
257  &pinfo->argnames);
258 
259  /* Paranoia: ignore the result if too few array entries */
260  if (n_arg_names < nargs)
261  pinfo->argnames = NULL;
262  }
263  else
264  pinfo->argnames = NULL;
265 
266  return pinfo;
267 }
#define GETSTRUCT(TUP)
Definition: htup_details.h:673
#define PointerGetDatum(X)
Definition: postgres.h:539
char * pstrdup(const char *in)
Definition: mcxt.c:1161
struct SQLFunctionParseInfo * SQLFunctionParseInfoPtr
Definition: functions.h:21
int errcode(int sqlerrcode)
Definition: elog.c:575
Oid get_call_expr_argtype(Node *expr, int argnum)
Definition: fmgr.c:2013
char * format_type_be(Oid type_oid)
Definition: format_type.c:328
unsigned int Oid
Definition: postgres_ext.h:31
#define ERROR
Definition: elog.h:43
#define ereport(elevel, rest)
Definition: elog.h:122
int get_func_input_arg_names(Datum proargnames, Datum proargmodes, char ***arg_names)
Definition: funcapi.c:988
void * palloc0(Size size)
Definition: mcxt.c:955
uintptr_t Datum
Definition: postgres.h:365
Datum SysCacheGetAttr(int cacheId, HeapTuple tup, AttrNumber attributeNumber, bool *isNull)
Definition: syscache.c:1368
FormData_pg_proc * Form_pg_proc
Definition: pg_proc.h:132
#define InvalidOid
Definition: postgres_ext.h:36
void * palloc(Size size)
Definition: mcxt.c:924
int errmsg(const char *fmt,...)
Definition: elog.c:797
#define NameStr(name)
Definition: c.h:576

◆ sql_fn_parser_setup()

void sql_fn_parser_setup ( struct ParseState pstate,
SQLFunctionParseInfoPtr  pinfo 
)

Definition at line 273 of file functions.c.

References ParseState::p_paramref_hook, ParseState::p_post_columnref_hook, ParseState::p_pre_columnref_hook, ParseState::p_ref_hook_state, sql_fn_param_ref(), and sql_fn_post_column_ref().

Referenced by fmgr_sql_validator(), init_sql_fcache(), inline_function(), and inline_set_returning_function().

274 {
275  pstate->p_pre_columnref_hook = NULL;
278  /* no need to use p_coerce_param_hook */
279  pstate->p_ref_hook_state = (void *) pinfo;
280 }
PostParseColumnRefHook p_post_columnref_hook
Definition: parse_node.h:213
ParseParamRefHook p_paramref_hook
Definition: parse_node.h:214
static Node * sql_fn_post_column_ref(ParseState *pstate, ColumnRef *cref, Node *var)
Definition: functions.c:286
void * p_ref_hook_state
Definition: parse_node.h:216
static Node * sql_fn_param_ref(ParseState *pstate, ParamRef *pref)
Definition: functions.c:404
PreParseColumnRefHook p_pre_columnref_hook
Definition: parse_node.h:212