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Diffstat (limited to 'src/backend/executor/functions.c')
| -rw-r--r-- | src/backend/executor/functions.c | 611 |
1 files changed, 0 insertions, 611 deletions
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c deleted file mode 100644 index c7b7c398eb2..00000000000 --- a/src/backend/executor/functions.c +++ /dev/null @@ -1,611 +0,0 @@ -/*------------------------------------------------------------------------- - * - * functions.c - * Routines to handle functions called from the executor - * - * 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/functions.c,v 1.52 2002/06/20 20:29:28 momjian Exp $ - * - *------------------------------------------------------------------------- - */ -#include "postgres.h" - -#include "access/heapam.h" -#include "catalog/pg_proc.h" -#include "catalog/pg_type.h" -#include "executor/execdefs.h" -#include "executor/executor.h" -#include "executor/functions.h" -#include "tcop/pquery.h" -#include "tcop/tcopprot.h" -#include "tcop/utility.h" -#include "utils/builtins.h" -#include "utils/syscache.h" - - -/* - * We have an execution_state record for each query in a function. - */ -typedef enum -{ - F_EXEC_START, F_EXEC_RUN, F_EXEC_DONE -} ExecStatus; - -typedef struct local_es -{ - QueryDesc *qd; - EState *estate; - struct local_es *next; - ExecStatus status; -} execution_state; - -#define LAST_POSTQUEL_COMMAND(es) ((es)->next == (execution_state *) NULL) - - -/* - * An SQLFunctionCache record is built during the first call, - * and linked to from the fn_extra field of the FmgrInfo struct. - */ - -typedef struct -{ - int typlen; /* length of the return type */ - bool typbyval; /* true if return type is pass by value */ - bool returnsTuple; /* true if return type is a tuple */ - bool shutdown_reg; /* true if registered shutdown callback */ - - TupleTableSlot *funcSlot; /* if one result we need to copy it before - * we end execution of the function and - * free stuff */ - - /* head of linked list of execution_state records */ - execution_state *func_state; -} SQLFunctionCache; - -typedef SQLFunctionCache *SQLFunctionCachePtr; - - -/* non-export function prototypes */ -static execution_state *init_execution_state(char *src, - Oid *argOidVect, int nargs); -static void init_sql_fcache(FmgrInfo *finfo); -static void postquel_start(execution_state *es); -static TupleTableSlot *postquel_getnext(execution_state *es); -static void postquel_end(execution_state *es); -static void postquel_sub_params(execution_state *es, FunctionCallInfo fcinfo); -static Datum postquel_execute(execution_state *es, - FunctionCallInfo fcinfo, - SQLFunctionCachePtr fcache); -static void ShutdownSQLFunction(Datum arg); - - -static execution_state * -init_execution_state(char *src, Oid *argOidVect, int nargs) -{ - execution_state *newes; - execution_state *nextes; - execution_state *preves; - List *queryTree_list, - *qtl_item; - - newes = (execution_state *) palloc(sizeof(execution_state)); - nextes = newes; - preves = (execution_state *) NULL; - - queryTree_list = pg_parse_and_rewrite(src, argOidVect, nargs); - - foreach(qtl_item, queryTree_list) - { - Query *queryTree = lfirst(qtl_item); - Plan *planTree; - EState *estate; - - planTree = pg_plan_query(queryTree); - - if (!nextes) - nextes = (execution_state *) palloc(sizeof(execution_state)); - if (preves) - preves->next = nextes; - - nextes->next = NULL; - nextes->status = F_EXEC_START; - - nextes->qd = CreateQueryDesc(queryTree, planTree, None, NULL); - estate = CreateExecutorState(); - - if (nargs > 0) - { - int i; - ParamListInfo paramLI; - - paramLI = (ParamListInfo) palloc((nargs + 1) * sizeof(ParamListInfoData)); - - MemSet(paramLI, 0, nargs * sizeof(ParamListInfoData)); - - estate->es_param_list_info = paramLI; - - for (i = 0; i < nargs; paramLI++, i++) - { - paramLI->kind = PARAM_NUM; - paramLI->id = i + 1; - paramLI->isnull = false; - paramLI->value = (Datum) NULL; - } - paramLI->kind = PARAM_INVALID; - } - else - estate->es_param_list_info = (ParamListInfo) NULL; - nextes->estate = estate; - preves = nextes; - nextes = (execution_state *) NULL; - } - - return newes; -} - - -static void -init_sql_fcache(FmgrInfo *finfo) -{ - Oid foid = finfo->fn_oid; - HeapTuple procedureTuple; - HeapTuple typeTuple; - Form_pg_proc procedureStruct; - Form_pg_type typeStruct; - SQLFunctionCachePtr fcache; - Oid *argOidVect; - char *src; - int nargs; - Datum tmp; - bool isNull; - - /* - * get the procedure tuple corresponding to the given function Oid - */ - procedureTuple = SearchSysCache(PROCOID, - ObjectIdGetDatum(foid), - 0, 0, 0); - if (!HeapTupleIsValid(procedureTuple)) - elog(ERROR, "init_sql_fcache: Cache lookup failed for procedure %u", - foid); - - procedureStruct = (Form_pg_proc) GETSTRUCT(procedureTuple); - - /* - * get the return type from the procedure tuple - */ - typeTuple = SearchSysCache(TYPEOID, - ObjectIdGetDatum(procedureStruct->prorettype), - 0, 0, 0); - if (!HeapTupleIsValid(typeTuple)) - elog(ERROR, "init_sql_fcache: Cache lookup failed for type %u", - procedureStruct->prorettype); - - typeStruct = (Form_pg_type) GETSTRUCT(typeTuple); - - fcache = (SQLFunctionCachePtr) palloc(sizeof(SQLFunctionCache)); - MemSet(fcache, 0, sizeof(SQLFunctionCache)); - - /* - * get the type length and by-value flag from the type tuple - */ - fcache->typlen = typeStruct->typlen; - if (typeStruct->typrelid == InvalidOid) - { - /* The return type is not a relation, so just use byval */ - fcache->typbyval = typeStruct->typbyval; - fcache->returnsTuple = false; - } - else - { - /* - * This is a hack. We assume here that any function returning a - * tuple returns it by reference. This needs to be fixed, since - * actually the mechanism isn't quite like return-by-reference. - */ - fcache->typbyval = false; - fcache->returnsTuple = true; - } - - /* - * If we are returning exactly one result then we have to copy tuples - * and by reference results because we have to end the execution - * before we return the results. When you do this everything - * allocated by the executor (i.e. slots and tuples) is freed. - */ - if (!finfo->fn_retset && !fcache->typbyval) - fcache->funcSlot = MakeTupleTableSlot(); - else - fcache->funcSlot = NULL; - - nargs = procedureStruct->pronargs; - - if (nargs > 0) - { - argOidVect = (Oid *) palloc(nargs * sizeof(Oid)); - memcpy(argOidVect, - procedureStruct->proargtypes, - nargs * sizeof(Oid)); - } - else - argOidVect = (Oid *) NULL; - - tmp = SysCacheGetAttr(PROCOID, - procedureTuple, - Anum_pg_proc_prosrc, - &isNull); - if (isNull) - elog(ERROR, "init_sql_fcache: null prosrc for procedure %u", - foid); - src = DatumGetCString(DirectFunctionCall1(textout, tmp)); - - fcache->func_state = init_execution_state(src, argOidVect, nargs); - - pfree(src); - - ReleaseSysCache(typeTuple); - ReleaseSysCache(procedureTuple); - - finfo->fn_extra = (void *) fcache; -} - - -static void -postquel_start(execution_state *es) -{ - /* - * Do nothing for utility commands. (create, destroy...) DZ - - * 30-8-1996 - */ - if (es->qd->operation == CMD_UTILITY) - return; - ExecutorStart(es->qd, es->estate); -} - -static TupleTableSlot * -postquel_getnext(execution_state *es) -{ - long count; - - if (es->qd->operation == CMD_UTILITY) - { - /* - * Process a utility command. (create, destroy...) DZ - 30-8-1996 - */ - ProcessUtility(es->qd->parsetree->utilityStmt, es->qd->dest, NULL); - if (!LAST_POSTQUEL_COMMAND(es)) - CommandCounterIncrement(); - return (TupleTableSlot *) NULL; - } - - /* If it's not the last command, just run it to completion */ - count = (LAST_POSTQUEL_COMMAND(es)) ? 1L : 0L; - - return ExecutorRun(es->qd, es->estate, ForwardScanDirection, count); -} - -static void -postquel_end(execution_state *es) -{ - /* - * Do nothing for utility commands. (create, destroy...) DZ - - * 30-8-1996 - */ - if (es->qd->operation == CMD_UTILITY) - return; - ExecutorEnd(es->qd, es->estate); -} - -static void -postquel_sub_params(execution_state *es, FunctionCallInfo fcinfo) -{ - EState *estate; - ParamListInfo paramLI; - - estate = es->estate; - paramLI = estate->es_param_list_info; - - while (paramLI->kind != PARAM_INVALID) - { - if (paramLI->kind == PARAM_NUM) - { - Assert(paramLI->id <= fcinfo->nargs); - paramLI->value = fcinfo->arg[paramLI->id - 1]; - paramLI->isnull = fcinfo->argnull[paramLI->id - 1]; - } - paramLI++; - } -} - -static TupleTableSlot * -copy_function_result(SQLFunctionCachePtr fcache, - TupleTableSlot *resultSlot) -{ - TupleTableSlot *funcSlot; - TupleDesc resultTd; - HeapTuple resultTuple; - HeapTuple newTuple; - - Assert(!TupIsNull(resultSlot)); - resultTuple = resultSlot->val; - - funcSlot = fcache->funcSlot; - - if (funcSlot == NULL) - return resultSlot; /* no need to copy result */ - - /* - * If first time through, we have to initialize the funcSlot's tuple - * descriptor. - */ - if (funcSlot->ttc_tupleDescriptor == NULL) - { - resultTd = CreateTupleDescCopy(resultSlot->ttc_tupleDescriptor); - ExecSetSlotDescriptor(funcSlot, resultTd, true); - ExecSetSlotDescriptorIsNew(funcSlot, true); - } - - newTuple = heap_copytuple(resultTuple); - - return ExecStoreTuple(newTuple, funcSlot, InvalidBuffer, true); -} - -static Datum -postquel_execute(execution_state *es, - FunctionCallInfo fcinfo, - SQLFunctionCachePtr fcache) -{ - TupleTableSlot *slot; - Datum value; - - /* - * It's more right place to do it (before - * postquel_start->ExecutorStart). Now - * ExecutorStart->ExecInitIndexScan->ExecEvalParam works ok. (But - * note: I HOPE we can do it here). - vadim 01/22/97 - */ - if (fcinfo->nargs > 0) - postquel_sub_params(es, fcinfo); - - if (es->status == F_EXEC_START) - { - postquel_start(es); - es->status = F_EXEC_RUN; - } - - slot = postquel_getnext(es); - - if (TupIsNull(slot)) - { - postquel_end(es); - es->status = F_EXEC_DONE; - fcinfo->isnull = true; - - /* - * If this isn't the last command for the function we have to - * increment the command counter so that subsequent commands can - * see changes made by previous ones. - */ - if (!LAST_POSTQUEL_COMMAND(es)) - CommandCounterIncrement(); - return (Datum) NULL; - } - - if (LAST_POSTQUEL_COMMAND(es)) - { - TupleTableSlot *resSlot; - - /* - * Copy the result. copy_function_result is smart enough to do - * nothing when no action is called for. This helps reduce the - * logic and code redundancy here. - */ - resSlot = copy_function_result(fcache, slot); - - /* - * If we are supposed to return a tuple, we return the tuple slot - * pointer converted to Datum. If we are supposed to return a - * simple value, then project out the first attribute of the - * result tuple (ie, take the first result column of the final - * SELECT). - */ - if (fcache->returnsTuple) - { - /* - * XXX do we need to remove junk attrs from the result tuple? - * Probably OK to leave them, as long as they are at the end. - */ - value = PointerGetDatum(resSlot); - fcinfo->isnull = false; - } - else - { - value = heap_getattr(resSlot->val, - 1, - resSlot->ttc_tupleDescriptor, - &(fcinfo->isnull)); - - /* - * Note: if result type is pass-by-reference then we are - * returning a pointer into the tuple copied by - * copy_function_result. This is OK. - */ - } - - /* - * If this is a single valued function we have to end the function - * execution now. - */ - if (!fcinfo->flinfo->fn_retset) - { - postquel_end(es); - es->status = F_EXEC_DONE; - } - - return value; - } - - /* - * If this isn't the last command for the function, we don't return - * any results, but we have to increment the command counter so that - * subsequent commands can see changes made by previous ones. - */ - CommandCounterIncrement(); - return (Datum) NULL; -} - -Datum -fmgr_sql(PG_FUNCTION_ARGS) -{ - MemoryContext oldcontext; - SQLFunctionCachePtr fcache; - execution_state *es; - Datum result = 0; - - /* - * Switch to context in which the fcache lives. This ensures that - * parsetrees, plans, etc, will have sufficient lifetime. The - * sub-executor is responsible for deleting per-tuple information. - */ - oldcontext = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt); - - /* - * Initialize fcache and execution state if first time through. - */ - fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra; - if (fcache == NULL) - { - init_sql_fcache(fcinfo->flinfo); - fcache = (SQLFunctionCachePtr) fcinfo->flinfo->fn_extra; - } - es = fcache->func_state; - Assert(es); - - /* - * Find first unfinished query in function. - */ - while (es && es->status == F_EXEC_DONE) - es = es->next; - - Assert(es); - - /* - * Execute each command in the function one after another until we're - * executing the final command and get a result or we run out of - * commands. - */ - while (es != (execution_state *) NULL) - { - result = postquel_execute(es, fcinfo, fcache); - if (es->status != F_EXEC_DONE) - break; - es = es->next; - } - - /* - * If we've gone through every command in this function, we are done. - */ - if (es == (execution_state *) NULL) - { - /* - * Reset the execution states to start over again - */ - es = fcache->func_state; - while (es) - { - es->status = F_EXEC_START; - es = es->next; - } - - /* - * Let caller know we're finished. - */ - if (fcinfo->flinfo->fn_retset) - { - ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo; - - if (rsi && IsA(rsi, ReturnSetInfo)) - rsi->isDone = ExprEndResult; - else - elog(ERROR, "Set-valued function called in context that cannot accept a set"); - fcinfo->isnull = true; - result = (Datum) 0; - - /* Deregister shutdown callback, if we made one */ - if (fcache->shutdown_reg) - { - UnregisterExprContextCallback(rsi->econtext, - ShutdownSQLFunction, - PointerGetDatum(fcache)); - fcache->shutdown_reg = false; - } - } - - MemoryContextSwitchTo(oldcontext); - - return result; - } - - /* - * If we got a result from a command within the function it has to be - * the final command. All others shouldn't be returning anything. - */ - Assert(LAST_POSTQUEL_COMMAND(es)); - - /* - * Let caller know we're not finished. - */ - if (fcinfo->flinfo->fn_retset) - { - ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo; - - if (rsi && IsA(rsi, ReturnSetInfo)) - rsi->isDone = ExprMultipleResult; - else - elog(ERROR, "Set-valued function called in context that cannot accept a set"); - - /* - * Ensure we will get shut down cleanly if the exprcontext is - * not run to completion. - */ - if (!fcache->shutdown_reg) - { - RegisterExprContextCallback(rsi->econtext, - ShutdownSQLFunction, - PointerGetDatum(fcache)); - fcache->shutdown_reg = true; - } - } - - MemoryContextSwitchTo(oldcontext); - - return result; -} - -/* - * callback function in case a function-returning-set needs to be shut down - * before it has been run to completion - */ -static void -ShutdownSQLFunction(Datum arg) -{ - SQLFunctionCachePtr fcache = (SQLFunctionCachePtr) DatumGetPointer(arg); - execution_state *es = fcache->func_state; - - while (es != NULL) - { - /* Shut down anything still running */ - if (es->status == F_EXEC_RUN) - postquel_end(es); - /* Reset states to START in case we're called again */ - es->status = F_EXEC_START; - es = es->next; - } - - /* execUtils will deregister the callback... */ - fcache->shutdown_reg = false; -} |