Rethink recently-added SPI interfaces.

SPI_execute_with_receiver and SPI_cursor_parse_open_with_paramlist are
new in v14 (cf. commit 2f48ede08).  Before they can get out the door,
let's change their APIs to follow the practice recently established by
SPI_prepare_extended etc: shove all optional arguments into a struct
that callers are supposed to pre-zero.  The hope is to allow future
addition of more options without either API breakage or a continuing
proliferation of new SPI entry points.  With that in mind, choose
slightly more generic names for them: SPI_execute_extended and
SPI_cursor_parse_open respectively.

Discussion: https://postgr.es/m/CAFj8pRCLPdDAETvR7Po7gC5y_ibkn_-bOzbeJb39WHms01194Q@mail.gmail.com

src/backend/executor/spi.c

@@ -538,6 +538,43 @@ SPI_exec(const char *src, long tcount)
 	return SPI_execute(src, false, tcount);
 }
 
+/* Parse, plan, and execute a query string, with extensible options */
+int
+SPI_execute_extended(const char *src,
+					 const SPIExecuteOptions *options)
+{
+	int			res;
+	_SPI_plan	plan;
+
+	if (src == NULL || options == NULL)
+		return SPI_ERROR_ARGUMENT;
+
+	res = _SPI_begin_call(true);
+	if (res < 0)
+		return res;
+
+	memset(&plan, 0, sizeof(_SPI_plan));
+	plan.magic = _SPI_PLAN_MAGIC;
+	plan.parse_mode = RAW_PARSE_DEFAULT;
+	plan.cursor_options = CURSOR_OPT_PARALLEL_OK;
+	if (options->params)
+	{
+		plan.parserSetup = options->params->parserSetup;
+		plan.parserSetupArg = options->params->parserSetupArg;
+	}
+
+	_SPI_prepare_oneshot_plan(src, &plan);
+
+	res = _SPI_execute_plan(&plan, options->params,
+							InvalidSnapshot, InvalidSnapshot,
+							options->read_only, options->no_snapshots,
+							true, options->tcount,
+							options->dest, options->owner);
+
+	_SPI_end_call(true);
+	return res;
+}
+
 /* Execute a previously prepared plan */
 int
 SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
@@ -715,52 +752,6 @@ SPI_execute_with_args(const char *src,
 	return res;
 }
 
-/*
- * SPI_execute_with_receiver -- plan and execute a query with arguments
- *
- * This is the same as SPI_execute_with_args except that parameters are
- * supplied through a ParamListInfo, and (if dest isn't NULL) we send
- * result tuples to the caller-supplied DestReceiver rather than through
- * the usual SPI output arrangements.
- */
-int
-SPI_execute_with_receiver(const char *src,
-						  ParamListInfo params,
-						  bool read_only, long tcount,
-						  DestReceiver *dest)
-{
-	int			res;
-	_SPI_plan	plan;
-
-	if (src == NULL || tcount < 0)
-		return SPI_ERROR_ARGUMENT;
-
-	res = _SPI_begin_call(true);
-	if (res < 0)
-		return res;
-
-	memset(&plan, 0, sizeof(_SPI_plan));
-	plan.magic = _SPI_PLAN_MAGIC;
-	plan.parse_mode = RAW_PARSE_DEFAULT;
-	plan.cursor_options = CURSOR_OPT_PARALLEL_OK;
-	if (params)
-	{
-		plan.parserSetup = params->parserSetup;
-		plan.parserSetupArg = params->parserSetupArg;
-	}
-
-	_SPI_prepare_oneshot_plan(src, &plan);
-
-	res = _SPI_execute_plan(&plan, params,
-							InvalidSnapshot, InvalidSnapshot,
-							read_only, false,
-							true, tcount,
-							dest, NULL);
-
-	_SPI_end_call(true);
-	return res;
-}
-
 SPIPlanPtr
 SPI_prepare(const char *src, int nargs, Oid *argtypes)
 {
@@ -1433,43 +1424,38 @@ SPI_cursor_open_with_paramlist(const char *name, SPIPlanPtr plan,
 	return SPI_cursor_open_internal(name, plan, params, read_only);
 }
 
-/*
- * SPI_cursor_parse_open_with_paramlist()
- *
- * Same as SPI_cursor_open_with_args except that parameters (if any) are passed
- * as a ParamListInfo, which supports dynamic parameter set determination
- */
+/* Parse a query and open it as a cursor */
 Portal
-SPI_cursor_parse_open_with_paramlist(const char *name,
-									 const char *src,
-									 ParamListInfo params,
-									 bool read_only, int cursorOptions)
+SPI_cursor_parse_open(const char *name,
+					  const char *src,
+					  const SPIParseOpenOptions *options)
 {
 	Portal		result;
 	_SPI_plan	plan;
 
-	if (src == NULL)
-		elog(ERROR, "SPI_cursor_parse_open_with_paramlist called with invalid arguments");
+	if (src == NULL || options == NULL)
+		elog(ERROR, "SPI_cursor_parse_open called with invalid arguments");
 
 	SPI_result = _SPI_begin_call(true);
 	if (SPI_result < 0)
-		elog(ERROR, "SPI_cursor_parse_open_with_paramlist called while not connected");
+		elog(ERROR, "SPI_cursor_parse_open called while not connected");
 
 	memset(&plan, 0, sizeof(_SPI_plan));
 	plan.magic = _SPI_PLAN_MAGIC;
 	plan.parse_mode = RAW_PARSE_DEFAULT;
-	plan.cursor_options = cursorOptions;
-	if (params)
+	plan.cursor_options = options->cursorOptions;
+	if (options->params)
 	{
-		plan.parserSetup = params->parserSetup;
-		plan.parserSetupArg = params->parserSetupArg;
+		plan.parserSetup = options->params->parserSetup;
+		plan.parserSetupArg = options->params->parserSetupArg;
 	}
 
 	_SPI_prepare_plan(src, &plan);
 
 	/* We needn't copy the plan; SPI_cursor_open_internal will do so */
 
-	result = SPI_cursor_open_internal(name, &plan, params, read_only);
+	result = SPI_cursor_open_internal(name, &plan,
+									  options->params, options->read_only);
 
 	/* And clean up */
 	_SPI_end_call(true);

src/include/executor/spi.h

@@ -42,7 +42,7 @@ typedef struct SPIPrepareOptions
 	int			cursorOptions;
 } SPIPrepareOptions;
 
-/* Optional arguments for SPI_execute_plan_extended */
+/* Optional arguments for SPI_execute[_plan]_extended */
 typedef struct SPIExecuteOptions
 {
 	ParamListInfo params;
@@ -53,6 +53,14 @@ typedef struct SPIExecuteOptions
 	ResourceOwner owner;
 } SPIExecuteOptions;
 
+/* Optional arguments for SPI_cursor_parse_open */
+typedef struct SPIParseOpenOptions
+{
+	ParamListInfo params;
+	int			cursorOptions;
+	bool		read_only;
+} SPIParseOpenOptions;
+
 /* Plans are opaque structs for standard users of SPI */
 typedef struct _SPI_plan *SPIPlanPtr;
 
@@ -105,6 +113,8 @@ extern int	SPI_connect(void);
 extern int	SPI_connect_ext(int options);
 extern int	SPI_finish(void);
 extern int	SPI_execute(const char *src, bool read_only, long tcount);
+extern int	SPI_execute_extended(const char *src,
+								 const SPIExecuteOptions *options);
 extern int	SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
 							 bool read_only, long tcount);
 extern int	SPI_execute_plan_extended(SPIPlanPtr plan,
@@ -124,10 +134,6 @@ extern int	SPI_execute_with_args(const char *src,
 								  int nargs, Oid *argtypes,
 								  Datum *Values, const char *Nulls,
 								  bool read_only, long tcount);
-extern int	SPI_execute_with_receiver(const char *src,
-									  ParamListInfo params,
-									  bool read_only, long tcount,
-									  DestReceiver *dest);
 extern SPIPlanPtr SPI_prepare(const char *src, int nargs, Oid *argtypes);
 extern SPIPlanPtr SPI_prepare_cursor(const char *src, int nargs, Oid *argtypes,
 									 int cursorOptions);
@@ -178,11 +184,9 @@ extern Portal SPI_cursor_open_with_args(const char *name,
 										bool read_only, int cursorOptions);
 extern Portal SPI_cursor_open_with_paramlist(const char *name, SPIPlanPtr plan,
 											 ParamListInfo params, bool read_only);
-extern Portal SPI_cursor_parse_open_with_paramlist(const char *name,
-												   const char *src,
-												   ParamListInfo params,
-												   bool read_only,
-												   int cursorOptions);
+extern Portal SPI_cursor_parse_open(const char *name,
+									const char *src,
+									const SPIParseOpenOptions *options);
 extern Portal SPI_cursor_find(const char *name);
 extern void SPI_cursor_fetch(Portal portal, bool forward, long count);
 extern void SPI_cursor_move(Portal portal, bool forward, long count);

src/pl/plpgsql/src/pl_exec.c

@@ -3603,6 +3603,7 @@ exec_stmt_return_query(PLpgSQL_execstate *estate,
 		Oid			restype;
 		int32		restypmod;
 		char	   *querystr;
+		SPIExecuteOptions options;
 
 		/*
 		 * Evaluate the string expression after the EXECUTE keyword. Its
@@ -3625,14 +3626,15 @@ exec_stmt_return_query(PLpgSQL_execstate *estate,
 		exec_eval_cleanup(estate);
 
 		/* Execute query, passing params if necessary */
-		rc = SPI_execute_with_receiver(querystr,
-									   exec_eval_using_params(estate,
-															  stmt->params),
-									   estate->readonly_func,
-									   0,
-									   treceiver);
+		memset(&options, 0, sizeof(options));
+		options.params = exec_eval_using_params(estate,
+												stmt->params);
+		options.read_only = estate->readonly_func;
+		options.dest = treceiver;
+
+		rc = SPI_execute_extended(querystr, &options);
 		if (rc < 0)
-			elog(ERROR, "SPI_execute_with_receiver failed executing query \"%s\": %s",
+			elog(ERROR, "SPI_execute_extended failed executing query \"%s\": %s",
 				 querystr, SPI_result_code_string(rc));
 	}
 
@@ -4402,6 +4404,7 @@ exec_stmt_dynexecute(PLpgSQL_execstate *estate,
 	char	   *querystr;
 	int			exec_res;
 	ParamListInfo paramLI;
+	SPIExecuteOptions options;
 	MemoryContext stmt_mcontext = get_stmt_mcontext(estate);
 
 	/*
@@ -4426,8 +4429,12 @@ exec_stmt_dynexecute(PLpgSQL_execstate *estate,
 	 * Execute the query without preparing a saved plan.
 	 */
 	paramLI = exec_eval_using_params(estate, stmt->params);
-	exec_res = SPI_execute_with_receiver(querystr, paramLI,
-										 estate->readonly_func, 0, NULL);
+
+	memset(&options, 0, sizeof(options));
+	options.params = paramLI;
+	options.read_only = estate->readonly_func;
+
+	exec_res = SPI_execute_extended(querystr, &options);
 
 	switch (exec_res)
 	{
@@ -4479,7 +4486,7 @@ exec_stmt_dynexecute(PLpgSQL_execstate *estate,
 			break;
 
 		default:
-			elog(ERROR, "SPI_execute_with_receiver failed executing query \"%s\": %s",
+			elog(ERROR, "SPI_execute_extended failed executing query \"%s\": %s",
 				 querystr, SPI_result_code_string(exec_res));
 			break;
 	}
@@ -8582,6 +8589,7 @@ exec_dynquery_with_params(PLpgSQL_execstate *estate,
 	Oid			restype;
 	int32		restypmod;
 	char	   *querystr;
+	SPIParseOpenOptions options;
 	MemoryContext stmt_mcontext = get_stmt_mcontext(estate);
 
 	/*
@@ -8603,16 +8611,16 @@ exec_dynquery_with_params(PLpgSQL_execstate *estate,
 	exec_eval_cleanup(estate);
 
 	/*
-	 * Open an implicit cursor for the query.  We use
-	 * SPI_cursor_parse_open_with_paramlist even when there are no params,
-	 * because this avoids making and freeing one copy of the plan.
+	 * Open an implicit cursor for the query.  We use SPI_cursor_parse_open
+	 * even when there are no params, because this avoids making and freeing
+	 * one copy of the plan.
 	 */
-	portal = SPI_cursor_parse_open_with_paramlist(portalname,
-												  querystr,
-												  exec_eval_using_params(estate,
-																		 params),
-												  estate->readonly_func,
-												  cursorOptions);
+	memset(&options, 0, sizeof(options));
+	options.params = exec_eval_using_params(estate, params);
+	options.cursorOptions = cursorOptions;
+	options.read_only = estate->readonly_func;
+
+	portal = SPI_cursor_parse_open(portalname, querystr, &options);
 
 	if (portal == NULL)
 		elog(ERROR, "could not open implicit cursor for query \"%s\": %s",