1 /*-------------------------------------------------------------------------
2  *
3  * functioncmds.c
4  *
5  *	  Routines for CREATE and DROP FUNCTION commands and CREATE and DROP
6  *	  CAST commands.
7  *
8  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
9  * Portions Copyright (c) 1994, Regents of the University of California
10  *
11  *
12  * IDENTIFICATION
13  *	  src/backend/commands/functioncmds.c
14  *
15  * DESCRIPTION
16  *	  These routines take the parse tree and pick out the
17  *	  appropriate arguments/flags, and pass the results to the
18  *	  corresponding "FooDefine" routines (in src/catalog) that do
19  *	  the actual catalog-munging.  These routines also verify permission
20  *	  of the user to execute the command.
21  *
22  * NOTES
23  *	  These things must be defined and committed in the following order:
24  *		"create function":
25  *				input/output, recv/send procedures
26  *		"create type":
27  *				type
28  *		"create operator":
29  *				operators
30  *
31  *-------------------------------------------------------------------------
32  */
33 #include "postgres.h"
34 
35 #include "access/genam.h"
36 #include "access/heapam.h"
37 #include "access/htup_details.h"
38 #include "access/sysattr.h"
39 #include "catalog/dependency.h"
40 #include "catalog/indexing.h"
41 #include "catalog/objectaccess.h"
42 #include "catalog/pg_aggregate.h"
43 #include "catalog/pg_cast.h"
44 #include "catalog/pg_language.h"
45 #include "catalog/pg_namespace.h"
46 #include "catalog/pg_proc.h"
47 #include "catalog/pg_proc_fn.h"
48 #include "catalog/pg_transform.h"
49 #include "catalog/pg_type.h"
50 #include "catalog/pg_type_fn.h"
51 #include "commands/alter.h"
52 #include "commands/defrem.h"
53 #include "commands/proclang.h"
54 #include "miscadmin.h"
55 #include "optimizer/var.h"
56 #include "parser/parse_coerce.h"
57 #include "parser/parse_collate.h"
58 #include "parser/parse_expr.h"
59 #include "parser/parse_func.h"
60 #include "parser/parse_type.h"
61 #include "utils/acl.h"
62 #include "utils/builtins.h"
63 #include "utils/fmgroids.h"
64 #include "utils/guc.h"
65 #include "utils/lsyscache.h"
66 #include "utils/rel.h"
67 #include "utils/syscache.h"
68 #include "utils/tqual.h"
69 
70 /*
71  *	 Examine the RETURNS clause of the CREATE FUNCTION statement
72  *	 and return information about it as *prorettype_p and *returnsSet.
73  *
74  * This is more complex than the average typename lookup because we want to
75  * allow a shell type to be used, or even created if the specified return type
76  * doesn't exist yet.  (Without this, there's no way to define the I/O procs
77  * for a new type.)  But SQL function creation won't cope, so error out if
78  * the target language is SQL.  (We do this here, not in the SQL-function
79  * validator, so as not to produce a NOTICE and then an ERROR for the same
80  * condition.)
81  */
82 static void
compute_return_type(TypeName * returnType,Oid languageOid,Oid * prorettype_p,bool * returnsSet_p)83 compute_return_type(TypeName *returnType, Oid languageOid,
84 					Oid *prorettype_p, bool *returnsSet_p)
85 {
86 	Oid			rettype;
87 	Type		typtup;
88 	AclResult	aclresult;
89 
90 	typtup = LookupTypeName(NULL, returnType, NULL, false);
91 
92 	if (typtup)
93 	{
94 		if (!((Form_pg_type) GETSTRUCT(typtup))->typisdefined)
95 		{
96 			if (languageOid == SQLlanguageId)
97 				ereport(ERROR,
98 						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
99 						 errmsg("SQL function cannot return shell type %s",
100 								TypeNameToString(returnType))));
101 			else
102 				ereport(NOTICE,
103 						(errcode(ERRCODE_WRONG_OBJECT_TYPE),
104 						 errmsg("return type %s is only a shell",
105 								TypeNameToString(returnType))));
106 		}
107 		rettype = typeTypeId(typtup);
108 		ReleaseSysCache(typtup);
109 	}
110 	else
111 	{
112 		char	   *typnam = TypeNameToString(returnType);
113 		Oid			namespaceId;
114 		AclResult	aclresult;
115 		char	   *typname;
116 		ObjectAddress address;
117 
118 		/*
119 		 * Only C-coded functions can be I/O functions.  We enforce this
120 		 * restriction here mainly to prevent littering the catalogs with
121 		 * shell types due to simple typos in user-defined function
122 		 * definitions.
123 		 */
124 		if (languageOid != INTERNALlanguageId &&
125 			languageOid != ClanguageId)
126 			ereport(ERROR,
127 					(errcode(ERRCODE_UNDEFINED_OBJECT),
128 					 errmsg("type \"%s\" does not exist", typnam)));
129 
130 		/* Reject if there's typmod decoration, too */
131 		if (returnType->typmods != NIL)
132 			ereport(ERROR,
133 					(errcode(ERRCODE_SYNTAX_ERROR),
134 					 errmsg("type modifier cannot be specified for shell type \"%s\"",
135 							typnam)));
136 
137 		/* Otherwise, go ahead and make a shell type */
138 		ereport(NOTICE,
139 				(errcode(ERRCODE_UNDEFINED_OBJECT),
140 				 errmsg("type \"%s\" is not yet defined", typnam),
141 				 errdetail("Creating a shell type definition.")));
142 		namespaceId = QualifiedNameGetCreationNamespace(returnType->names,
143 														&typname);
144 		aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(),
145 										  ACL_CREATE);
146 		if (aclresult != ACLCHECK_OK)
147 			aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
148 						   get_namespace_name(namespaceId));
149 		address = TypeShellMake(typname, namespaceId, GetUserId());
150 		rettype = address.objectId;
151 		Assert(OidIsValid(rettype));
152 	}
153 
154 	aclresult = pg_type_aclcheck(rettype, GetUserId(), ACL_USAGE);
155 	if (aclresult != ACLCHECK_OK)
156 		aclcheck_error_type(aclresult, rettype);
157 
158 	*prorettype_p = rettype;
159 	*returnsSet_p = returnType->setof;
160 }
161 
162 /*
163  * Interpret the function parameter list of a CREATE FUNCTION or
164  * CREATE AGGREGATE statement.
165  *
166  * Input parameters:
167  * parameters: list of FunctionParameter structs
168  * languageOid: OID of function language (InvalidOid if it's CREATE AGGREGATE)
169  * is_aggregate: needed only to determine error handling
170  *
171  * Results are stored into output parameters.  parameterTypes must always
172  * be created, but the other arrays are set to NULL if not needed.
173  * variadicArgType is set to the variadic array type if there's a VARIADIC
174  * parameter (there can be only one); or to InvalidOid if not.
175  * requiredResultType is set to InvalidOid if there are no OUT parameters,
176  * else it is set to the OID of the implied result type.
177  */
178 void
interpret_function_parameter_list(ParseState * pstate,List * parameters,Oid languageOid,bool is_aggregate,oidvector ** parameterTypes,ArrayType ** allParameterTypes,ArrayType ** parameterModes,ArrayType ** parameterNames,List ** parameterDefaults,Oid * variadicArgType,Oid * requiredResultType)179 interpret_function_parameter_list(ParseState *pstate,
180 								  List *parameters,
181 								  Oid languageOid,
182 								  bool is_aggregate,
183 								  oidvector **parameterTypes,
184 								  ArrayType **allParameterTypes,
185 								  ArrayType **parameterModes,
186 								  ArrayType **parameterNames,
187 								  List **parameterDefaults,
188 								  Oid *variadicArgType,
189 								  Oid *requiredResultType)
190 {
191 	int			parameterCount = list_length(parameters);
192 	Oid		   *inTypes;
193 	int			inCount = 0;
194 	Datum	   *allTypes;
195 	Datum	   *paramModes;
196 	Datum	   *paramNames;
197 	int			outCount = 0;
198 	int			varCount = 0;
199 	bool		have_names = false;
200 	bool		have_defaults = false;
201 	ListCell   *x;
202 	int			i;
203 
204 	*variadicArgType = InvalidOid;	/* default result */
205 	*requiredResultType = InvalidOid;	/* default result */
206 
207 	inTypes = (Oid *) palloc(parameterCount * sizeof(Oid));
208 	allTypes = (Datum *) palloc(parameterCount * sizeof(Datum));
209 	paramModes = (Datum *) palloc(parameterCount * sizeof(Datum));
210 	paramNames = (Datum *) palloc0(parameterCount * sizeof(Datum));
211 	*parameterDefaults = NIL;
212 
213 	/* Scan the list and extract data into work arrays */
214 	i = 0;
215 	foreach(x, parameters)
216 	{
217 		FunctionParameter *fp = (FunctionParameter *) lfirst(x);
218 		TypeName   *t = fp->argType;
219 		bool		isinput = false;
220 		Oid			toid;
221 		Type		typtup;
222 		AclResult	aclresult;
223 
224 		typtup = LookupTypeName(NULL, t, NULL, false);
225 		if (typtup)
226 		{
227 			if (!((Form_pg_type) GETSTRUCT(typtup))->typisdefined)
228 			{
229 				/* As above, hard error if language is SQL */
230 				if (languageOid == SQLlanguageId)
231 					ereport(ERROR,
232 							(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
233 							 errmsg("SQL function cannot accept shell type %s",
234 									TypeNameToString(t))));
235 				/* We don't allow creating aggregates on shell types either */
236 				else if (is_aggregate)
237 					ereport(ERROR,
238 							(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
239 							 errmsg("aggregate cannot accept shell type %s",
240 									TypeNameToString(t))));
241 				else
242 					ereport(NOTICE,
243 							(errcode(ERRCODE_WRONG_OBJECT_TYPE),
244 							 errmsg("argument type %s is only a shell",
245 									TypeNameToString(t))));
246 			}
247 			toid = typeTypeId(typtup);
248 			ReleaseSysCache(typtup);
249 		}
250 		else
251 		{
252 			ereport(ERROR,
253 					(errcode(ERRCODE_UNDEFINED_OBJECT),
254 					 errmsg("type %s does not exist",
255 							TypeNameToString(t))));
256 			toid = InvalidOid;	/* keep compiler quiet */
257 		}
258 
259 		aclresult = pg_type_aclcheck(toid, GetUserId(), ACL_USAGE);
260 		if (aclresult != ACLCHECK_OK)
261 			aclcheck_error_type(aclresult, toid);
262 
263 		if (t->setof)
264 		{
265 			if (is_aggregate)
266 				ereport(ERROR,
267 						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
268 						 errmsg("aggregates cannot accept set arguments")));
269 			else
270 				ereport(ERROR,
271 						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
272 						 errmsg("functions cannot accept set arguments")));
273 		}
274 
275 		/* handle input parameters */
276 		if (fp->mode != FUNC_PARAM_OUT && fp->mode != FUNC_PARAM_TABLE)
277 		{
278 			/* other input parameters can't follow a VARIADIC parameter */
279 			if (varCount > 0)
280 				ereport(ERROR,
281 						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
282 						 errmsg("VARIADIC parameter must be the last input parameter")));
283 			inTypes[inCount++] = toid;
284 			isinput = true;
285 		}
286 
287 		/* handle output parameters */
288 		if (fp->mode != FUNC_PARAM_IN && fp->mode != FUNC_PARAM_VARIADIC)
289 		{
290 			if (outCount == 0)	/* save first output param's type */
291 				*requiredResultType = toid;
292 			outCount++;
293 		}
294 
295 		if (fp->mode == FUNC_PARAM_VARIADIC)
296 		{
297 			*variadicArgType = toid;
298 			varCount++;
299 			/* validate variadic parameter type */
300 			switch (toid)
301 			{
302 				case ANYARRAYOID:
303 				case ANYOID:
304 					/* okay */
305 					break;
306 				default:
307 					if (!OidIsValid(get_element_type(toid)))
308 						ereport(ERROR,
309 								(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
310 								 errmsg("VARIADIC parameter must be an array")));
311 					break;
312 			}
313 		}
314 
315 		allTypes[i] = ObjectIdGetDatum(toid);
316 
317 		paramModes[i] = CharGetDatum(fp->mode);
318 
319 		if (fp->name && fp->name[0])
320 		{
321 			ListCell   *px;
322 
323 			/*
324 			 * As of Postgres 9.0 we disallow using the same name for two
325 			 * input or two output function parameters.  Depending on the
326 			 * function's language, conflicting input and output names might
327 			 * be bad too, but we leave it to the PL to complain if so.
328 			 */
329 			foreach(px, parameters)
330 			{
331 				FunctionParameter *prevfp = (FunctionParameter *) lfirst(px);
332 
333 				if (prevfp == fp)
334 					break;
335 				/* pure in doesn't conflict with pure out */
336 				if ((fp->mode == FUNC_PARAM_IN ||
337 					 fp->mode == FUNC_PARAM_VARIADIC) &&
338 					(prevfp->mode == FUNC_PARAM_OUT ||
339 					 prevfp->mode == FUNC_PARAM_TABLE))
340 					continue;
341 				if ((prevfp->mode == FUNC_PARAM_IN ||
342 					 prevfp->mode == FUNC_PARAM_VARIADIC) &&
343 					(fp->mode == FUNC_PARAM_OUT ||
344 					 fp->mode == FUNC_PARAM_TABLE))
345 					continue;
346 				if (prevfp->name && prevfp->name[0] &&
347 					strcmp(prevfp->name, fp->name) == 0)
348 					ereport(ERROR,
349 							(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
350 							 errmsg("parameter name \"%s\" used more than once",
351 									fp->name)));
352 			}
353 
354 			paramNames[i] = CStringGetTextDatum(fp->name);
355 			have_names = true;
356 		}
357 
358 		if (fp->defexpr)
359 		{
360 			Node	   *def;
361 
362 			if (!isinput)
363 				ereport(ERROR,
364 						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
365 						 errmsg("only input parameters can have default values")));
366 
367 			def = transformExpr(pstate, fp->defexpr,
368 								EXPR_KIND_FUNCTION_DEFAULT);
369 			def = coerce_to_specific_type(pstate, def, toid, "DEFAULT");
370 			assign_expr_collations(pstate, def);
371 
372 			/*
373 			 * Make sure no variables are referred to (this is probably dead
374 			 * code now that add_missing_from is history).
375 			 */
376 			if (list_length(pstate->p_rtable) != 0 ||
377 				contain_var_clause(def))
378 				ereport(ERROR,
379 						(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
380 						 errmsg("cannot use table references in parameter default value")));
381 
382 			/*
383 			 * transformExpr() should have already rejected subqueries,
384 			 * aggregates, and window functions, based on the EXPR_KIND_ for a
385 			 * default expression.
386 			 *
387 			 * It can't return a set either --- but coerce_to_specific_type
388 			 * already checked that for us.
389 			 *
390 			 * Note: the point of these restrictions is to ensure that an
391 			 * expression that, on its face, hasn't got subplans, aggregates,
392 			 * etc cannot suddenly have them after function default arguments
393 			 * are inserted.
394 			 */
395 
396 			*parameterDefaults = lappend(*parameterDefaults, def);
397 			have_defaults = true;
398 		}
399 		else
400 		{
401 			if (isinput && have_defaults)
402 				ereport(ERROR,
403 						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
404 						 errmsg("input parameters after one with a default value must also have defaults")));
405 		}
406 
407 		i++;
408 	}
409 
410 	/* Now construct the proper outputs as needed */
411 	*parameterTypes = buildoidvector(inTypes, inCount);
412 
413 	if (outCount > 0 || varCount > 0)
414 	{
415 		*allParameterTypes = construct_array(allTypes, parameterCount, OIDOID,
416 											 sizeof(Oid), true, 'i');
417 		*parameterModes = construct_array(paramModes, parameterCount, CHAROID,
418 										  1, true, 'c');
419 		if (outCount > 1)
420 			*requiredResultType = RECORDOID;
421 		/* otherwise we set requiredResultType correctly above */
422 	}
423 	else
424 	{
425 		*allParameterTypes = NULL;
426 		*parameterModes = NULL;
427 	}
428 
429 	if (have_names)
430 	{
431 		for (i = 0; i < parameterCount; i++)
432 		{
433 			if (paramNames[i] == PointerGetDatum(NULL))
434 				paramNames[i] = CStringGetTextDatum("");
435 		}
436 		*parameterNames = construct_array(paramNames, parameterCount, TEXTOID,
437 										  -1, false, 'i');
438 	}
439 	else
440 		*parameterNames = NULL;
441 }
442 
443 
444 /*
445  * Recognize one of the options that can be passed to both CREATE
446  * FUNCTION and ALTER FUNCTION and return it via one of the out
447  * parameters. Returns true if the passed option was recognized. If
448  * the out parameter we were going to assign to points to non-NULL,
449  * raise a duplicate-clause error.  (We don't try to detect duplicate
450  * SET parameters though --- if you're redundant, the last one wins.)
451  */
452 static bool
compute_common_attribute(ParseState * pstate,DefElem * defel,DefElem ** volatility_item,DefElem ** strict_item,DefElem ** security_item,DefElem ** leakproof_item,List ** set_items,DefElem ** cost_item,DefElem ** rows_item,DefElem ** parallel_item)453 compute_common_attribute(ParseState *pstate,
454 						 DefElem *defel,
455 						 DefElem **volatility_item,
456 						 DefElem **strict_item,
457 						 DefElem **security_item,
458 						 DefElem **leakproof_item,
459 						 List **set_items,
460 						 DefElem **cost_item,
461 						 DefElem **rows_item,
462 						 DefElem **parallel_item)
463 {
464 	if (strcmp(defel->defname, "volatility") == 0)
465 	{
466 		if (*volatility_item)
467 			goto duplicate_error;
468 
469 		*volatility_item = defel;
470 	}
471 	else if (strcmp(defel->defname, "strict") == 0)
472 	{
473 		if (*strict_item)
474 			goto duplicate_error;
475 
476 		*strict_item = defel;
477 	}
478 	else if (strcmp(defel->defname, "security") == 0)
479 	{
480 		if (*security_item)
481 			goto duplicate_error;
482 
483 		*security_item = defel;
484 	}
485 	else if (strcmp(defel->defname, "leakproof") == 0)
486 	{
487 		if (*leakproof_item)
488 			goto duplicate_error;
489 
490 		*leakproof_item = defel;
491 	}
492 	else if (strcmp(defel->defname, "set") == 0)
493 	{
494 		*set_items = lappend(*set_items, defel->arg);
495 	}
496 	else if (strcmp(defel->defname, "cost") == 0)
497 	{
498 		if (*cost_item)
499 			goto duplicate_error;
500 
501 		*cost_item = defel;
502 	}
503 	else if (strcmp(defel->defname, "rows") == 0)
504 	{
505 		if (*rows_item)
506 			goto duplicate_error;
507 
508 		*rows_item = defel;
509 	}
510 	else if (strcmp(defel->defname, "parallel") == 0)
511 	{
512 		if (*parallel_item)
513 			goto duplicate_error;
514 
515 		*parallel_item = defel;
516 	}
517 	else
518 		return false;
519 
520 	/* Recognized an option */
521 	return true;
522 
523 duplicate_error:
524 	ereport(ERROR,
525 			(errcode(ERRCODE_SYNTAX_ERROR),
526 			 errmsg("conflicting or redundant options"),
527 			 parser_errposition(pstate, defel->location)));
528 	return false;				/* keep compiler quiet */
529 }
530 
531 static char
interpret_func_volatility(DefElem * defel)532 interpret_func_volatility(DefElem *defel)
533 {
534 	char	   *str = strVal(defel->arg);
535 
536 	if (strcmp(str, "immutable") == 0)
537 		return PROVOLATILE_IMMUTABLE;
538 	else if (strcmp(str, "stable") == 0)
539 		return PROVOLATILE_STABLE;
540 	else if (strcmp(str, "volatile") == 0)
541 		return PROVOLATILE_VOLATILE;
542 	else
543 	{
544 		elog(ERROR, "invalid volatility \"%s\"", str);
545 		return 0;				/* keep compiler quiet */
546 	}
547 }
548 
549 static char
interpret_func_parallel(DefElem * defel)550 interpret_func_parallel(DefElem *defel)
551 {
552 	char	   *str = strVal(defel->arg);
553 
554 	if (strcmp(str, "safe") == 0)
555 		return PROPARALLEL_SAFE;
556 	else if (strcmp(str, "unsafe") == 0)
557 		return PROPARALLEL_UNSAFE;
558 	else if (strcmp(str, "restricted") == 0)
559 		return PROPARALLEL_RESTRICTED;
560 	else
561 	{
562 		ereport(ERROR,
563 				(errcode(ERRCODE_SYNTAX_ERROR),
564 				 errmsg("parameter \"parallel\" must be SAFE, RESTRICTED, or UNSAFE")));
565 		return PROPARALLEL_UNSAFE;	/* keep compiler quiet */
566 	}
567 }
568 
569 /*
570  * Update a proconfig value according to a list of VariableSetStmt items.
571  *
572  * The input and result may be NULL to signify a null entry.
573  */
574 static ArrayType *
update_proconfig_value(ArrayType * a,List * set_items)575 update_proconfig_value(ArrayType *a, List *set_items)
576 {
577 	ListCell   *l;
578 
579 	foreach(l, set_items)
580 	{
581 		VariableSetStmt *sstmt = lfirst_node(VariableSetStmt, l);
582 
583 		if (sstmt->kind == VAR_RESET_ALL)
584 			a = NULL;
585 		else
586 		{
587 			char	   *valuestr = ExtractSetVariableArgs(sstmt);
588 
589 			if (valuestr)
590 				a = GUCArrayAdd(a, sstmt->name, valuestr);
591 			else				/* RESET */
592 				a = GUCArrayDelete(a, sstmt->name);
593 		}
594 	}
595 
596 	return a;
597 }
598 
599 
600 /*
601  * Dissect the list of options assembled in gram.y into function
602  * attributes.
603  */
604 static void
compute_attributes_sql_style(ParseState * pstate,List * options,List ** as,char ** language,Node ** transform,bool * windowfunc_p,char * volatility_p,bool * strict_p,bool * security_definer,bool * leakproof_p,ArrayType ** proconfig,float4 * procost,float4 * prorows,char * parallel_p)605 compute_attributes_sql_style(ParseState *pstate,
606 							 List *options,
607 							 List **as,
608 							 char **language,
609 							 Node **transform,
610 							 bool *windowfunc_p,
611 							 char *volatility_p,
612 							 bool *strict_p,
613 							 bool *security_definer,
614 							 bool *leakproof_p,
615 							 ArrayType **proconfig,
616 							 float4 *procost,
617 							 float4 *prorows,
618 							 char *parallel_p)
619 {
620 	ListCell   *option;
621 	DefElem    *as_item = NULL;
622 	DefElem    *language_item = NULL;
623 	DefElem    *transform_item = NULL;
624 	DefElem    *windowfunc_item = NULL;
625 	DefElem    *volatility_item = NULL;
626 	DefElem    *strict_item = NULL;
627 	DefElem    *security_item = NULL;
628 	DefElem    *leakproof_item = NULL;
629 	List	   *set_items = NIL;
630 	DefElem    *cost_item = NULL;
631 	DefElem    *rows_item = NULL;
632 	DefElem    *parallel_item = NULL;
633 
634 	foreach(option, options)
635 	{
636 		DefElem    *defel = (DefElem *) lfirst(option);
637 
638 		if (strcmp(defel->defname, "as") == 0)
639 		{
640 			if (as_item)
641 				ereport(ERROR,
642 						(errcode(ERRCODE_SYNTAX_ERROR),
643 						 errmsg("conflicting or redundant options"),
644 						 parser_errposition(pstate, defel->location)));
645 			as_item = defel;
646 		}
647 		else if (strcmp(defel->defname, "language") == 0)
648 		{
649 			if (language_item)
650 				ereport(ERROR,
651 						(errcode(ERRCODE_SYNTAX_ERROR),
652 						 errmsg("conflicting or redundant options"),
653 						 parser_errposition(pstate, defel->location)));
654 			language_item = defel;
655 		}
656 		else if (strcmp(defel->defname, "transform") == 0)
657 		{
658 			if (transform_item)
659 				ereport(ERROR,
660 						(errcode(ERRCODE_SYNTAX_ERROR),
661 						 errmsg("conflicting or redundant options"),
662 						 parser_errposition(pstate, defel->location)));
663 			transform_item = defel;
664 		}
665 		else if (strcmp(defel->defname, "window") == 0)
666 		{
667 			if (windowfunc_item)
668 				ereport(ERROR,
669 						(errcode(ERRCODE_SYNTAX_ERROR),
670 						 errmsg("conflicting or redundant options"),
671 						 parser_errposition(pstate, defel->location)));
672 			windowfunc_item = defel;
673 		}
674 		else if (compute_common_attribute(pstate,
675 										  defel,
676 										  &volatility_item,
677 										  &strict_item,
678 										  &security_item,
679 										  &leakproof_item,
680 										  &set_items,
681 										  &cost_item,
682 										  &rows_item,
683 										  &parallel_item))
684 		{
685 			/* recognized common option */
686 			continue;
687 		}
688 		else
689 			elog(ERROR, "option \"%s\" not recognized",
690 				 defel->defname);
691 	}
692 
693 	/* process required items */
694 	if (as_item)
695 		*as = (List *) as_item->arg;
696 	else
697 	{
698 		ereport(ERROR,
699 				(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
700 				 errmsg("no function body specified")));
701 		*as = NIL;				/* keep compiler quiet */
702 	}
703 
704 	if (language_item)
705 		*language = strVal(language_item->arg);
706 	else
707 	{
708 		ereport(ERROR,
709 				(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
710 				 errmsg("no language specified")));
711 		*language = NULL;		/* keep compiler quiet */
712 	}
713 
714 	/* process optional items */
715 	if (transform_item)
716 		*transform = transform_item->arg;
717 	if (windowfunc_item)
718 		*windowfunc_p = intVal(windowfunc_item->arg);
719 	if (volatility_item)
720 		*volatility_p = interpret_func_volatility(volatility_item);
721 	if (strict_item)
722 		*strict_p = intVal(strict_item->arg);
723 	if (security_item)
724 		*security_definer = intVal(security_item->arg);
725 	if (leakproof_item)
726 		*leakproof_p = intVal(leakproof_item->arg);
727 	if (set_items)
728 		*proconfig = update_proconfig_value(NULL, set_items);
729 	if (cost_item)
730 	{
731 		*procost = defGetNumeric(cost_item);
732 		if (*procost <= 0)
733 			ereport(ERROR,
734 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
735 					 errmsg("COST must be positive")));
736 	}
737 	if (rows_item)
738 	{
739 		*prorows = defGetNumeric(rows_item);
740 		if (*prorows <= 0)
741 			ereport(ERROR,
742 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
743 					 errmsg("ROWS must be positive")));
744 	}
745 	if (parallel_item)
746 		*parallel_p = interpret_func_parallel(parallel_item);
747 }
748 
749 
750 /*-------------
751  *	 Interpret the parameters *parameters and return their contents via
752  *	 *isStrict_p and *volatility_p.
753  *
754  *	These parameters supply optional information about a function.
755  *	All have defaults if not specified. Parameters:
756  *
757  *	 * isStrict means the function should not be called when any NULL
758  *	   inputs are present; instead a NULL result value should be assumed.
759  *
760  *	 * volatility tells the optimizer whether the function's result can
761  *	   be assumed to be repeatable over multiple evaluations.
762  *------------
763  */
764 static void
compute_attributes_with_style(ParseState * pstate,List * parameters,bool * isStrict_p,char * volatility_p)765 compute_attributes_with_style(ParseState *pstate, List *parameters, bool *isStrict_p, char *volatility_p)
766 {
767 	ListCell   *pl;
768 
769 	foreach(pl, parameters)
770 	{
771 		DefElem    *param = (DefElem *) lfirst(pl);
772 
773 		if (pg_strcasecmp(param->defname, "isstrict") == 0)
774 			*isStrict_p = defGetBoolean(param);
775 		else if (pg_strcasecmp(param->defname, "iscachable") == 0)
776 		{
777 			/* obsolete spelling of isImmutable */
778 			if (defGetBoolean(param))
779 				*volatility_p = PROVOLATILE_IMMUTABLE;
780 		}
781 		else
782 			ereport(WARNING,
783 					(errcode(ERRCODE_SYNTAX_ERROR),
784 					 errmsg("unrecognized function attribute \"%s\" ignored",
785 							param->defname),
786 					 parser_errposition(pstate, param->location)));
787 	}
788 }
789 
790 
791 /*
792  * For a dynamically linked C language object, the form of the clause is
793  *
794  *	   AS <object file name> [, <link symbol name> ]
795  *
796  * In all other cases
797  *
798  *	   AS <object reference, or sql code>
799  */
800 static void
interpret_AS_clause(Oid languageOid,const char * languageName,char * funcname,List * as,char ** prosrc_str_p,char ** probin_str_p)801 interpret_AS_clause(Oid languageOid, const char *languageName,
802 					char *funcname, List *as,
803 					char **prosrc_str_p, char **probin_str_p)
804 {
805 	Assert(as != NIL);
806 
807 	if (languageOid == ClanguageId)
808 	{
809 		/*
810 		 * For "C" language, store the file name in probin and, when given,
811 		 * the link symbol name in prosrc.  If link symbol is omitted,
812 		 * substitute procedure name.  We also allow link symbol to be
813 		 * specified as "-", since that was the habit in PG versions before
814 		 * 8.4, and there might be dump files out there that don't translate
815 		 * that back to "omitted".
816 		 */
817 		*probin_str_p = strVal(linitial(as));
818 		if (list_length(as) == 1)
819 			*prosrc_str_p = funcname;
820 		else
821 		{
822 			*prosrc_str_p = strVal(lsecond(as));
823 			if (strcmp(*prosrc_str_p, "-") == 0)
824 				*prosrc_str_p = funcname;
825 		}
826 	}
827 	else
828 	{
829 		/* Everything else wants the given string in prosrc. */
830 		*prosrc_str_p = strVal(linitial(as));
831 		*probin_str_p = NULL;
832 
833 		if (list_length(as) != 1)
834 			ereport(ERROR,
835 					(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
836 					 errmsg("only one AS item needed for language \"%s\"",
837 							languageName)));
838 
839 		if (languageOid == INTERNALlanguageId)
840 		{
841 			/*
842 			 * In PostgreSQL versions before 6.5, the SQL name of the created
843 			 * function could not be different from the internal name, and
844 			 * "prosrc" wasn't used.  So there is code out there that does
845 			 * CREATE FUNCTION xyz AS '' LANGUAGE internal. To preserve some
846 			 * modicum of backwards compatibility, accept an empty "prosrc"
847 			 * value as meaning the supplied SQL function name.
848 			 */
849 			if (strlen(*prosrc_str_p) == 0)
850 				*prosrc_str_p = funcname;
851 		}
852 	}
853 }
854 
855 
856 /*
857  * CreateFunction
858  *	 Execute a CREATE FUNCTION utility statement.
859  */
860 ObjectAddress
CreateFunction(ParseState * pstate,CreateFunctionStmt * stmt)861 CreateFunction(ParseState *pstate, CreateFunctionStmt *stmt)
862 {
863 	char	   *probin_str;
864 	char	   *prosrc_str;
865 	Oid			prorettype;
866 	bool		returnsSet;
867 	char	   *language;
868 	Oid			languageOid;
869 	Oid			languageValidator;
870 	Node	   *transformDefElem = NULL;
871 	char	   *funcname;
872 	Oid			namespaceId;
873 	AclResult	aclresult;
874 	oidvector  *parameterTypes;
875 	ArrayType  *allParameterTypes;
876 	ArrayType  *parameterModes;
877 	ArrayType  *parameterNames;
878 	List	   *parameterDefaults;
879 	Oid			variadicArgType;
880 	List	   *trftypes_list = NIL;
881 	ArrayType  *trftypes;
882 	Oid			requiredResultType;
883 	bool		isWindowFunc,
884 				isStrict,
885 				security,
886 				isLeakProof;
887 	char		volatility;
888 	ArrayType  *proconfig;
889 	float4		procost;
890 	float4		prorows;
891 	HeapTuple	languageTuple;
892 	Form_pg_language languageStruct;
893 	List	   *as_clause;
894 	char		parallel;
895 
896 	/* Convert list of names to a name and namespace */
897 	namespaceId = QualifiedNameGetCreationNamespace(stmt->funcname,
898 													&funcname);
899 
900 	/* Check we have creation rights in target namespace */
901 	aclresult = pg_namespace_aclcheck(namespaceId, GetUserId(), ACL_CREATE);
902 	if (aclresult != ACLCHECK_OK)
903 		aclcheck_error(aclresult, ACL_KIND_NAMESPACE,
904 					   get_namespace_name(namespaceId));
905 
906 	/* default attributes */
907 	isWindowFunc = false;
908 	isStrict = false;
909 	security = false;
910 	isLeakProof = false;
911 	volatility = PROVOLATILE_VOLATILE;
912 	proconfig = NULL;
913 	procost = -1;				/* indicates not set */
914 	prorows = -1;				/* indicates not set */
915 	parallel = PROPARALLEL_UNSAFE;
916 
917 	/* override attributes from explicit list */
918 	compute_attributes_sql_style(pstate,
919 								 stmt->options,
920 								 &as_clause, &language, &transformDefElem,
921 								 &isWindowFunc, &volatility,
922 								 &isStrict, &security, &isLeakProof,
923 								 &proconfig, &procost, &prorows, &parallel);
924 
925 	/* Look up the language and validate permissions */
926 	languageTuple = SearchSysCache1(LANGNAME, PointerGetDatum(language));
927 	if (!HeapTupleIsValid(languageTuple))
928 		ereport(ERROR,
929 				(errcode(ERRCODE_UNDEFINED_OBJECT),
930 				 errmsg("language \"%s\" does not exist", language),
931 				 (PLTemplateExists(language) ?
932 				  errhint("Use CREATE LANGUAGE to load the language into the database.") : 0)));
933 
934 	languageOid = HeapTupleGetOid(languageTuple);
935 	languageStruct = (Form_pg_language) GETSTRUCT(languageTuple);
936 
937 	if (languageStruct->lanpltrusted)
938 	{
939 		/* if trusted language, need USAGE privilege */
940 		AclResult	aclresult;
941 
942 		aclresult = pg_language_aclcheck(languageOid, GetUserId(), ACL_USAGE);
943 		if (aclresult != ACLCHECK_OK)
944 			aclcheck_error(aclresult, ACL_KIND_LANGUAGE,
945 						   NameStr(languageStruct->lanname));
946 	}
947 	else
948 	{
949 		/* if untrusted language, must be superuser */
950 		if (!superuser())
951 			aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_LANGUAGE,
952 						   NameStr(languageStruct->lanname));
953 	}
954 
955 	languageValidator = languageStruct->lanvalidator;
956 
957 	ReleaseSysCache(languageTuple);
958 
959 	/*
960 	 * Only superuser is allowed to create leakproof functions because
961 	 * leakproof functions can see tuples which have not yet been filtered out
962 	 * by security barrier views or row level security policies.
963 	 */
964 	if (isLeakProof && !superuser())
965 		ereport(ERROR,
966 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
967 				 errmsg("only superuser can define a leakproof function")));
968 
969 	if (transformDefElem)
970 	{
971 		ListCell   *lc;
972 
973 		foreach(lc, castNode(List, transformDefElem))
974 		{
975 			Oid			typeid = typenameTypeId(NULL,
976 												lfirst_node(TypeName, lc));
977 			Oid			elt = get_base_element_type(typeid);
978 
979 			typeid = elt ? elt : typeid;
980 
981 			get_transform_oid(typeid, languageOid, false);
982 			trftypes_list = lappend_oid(trftypes_list, typeid);
983 		}
984 	}
985 
986 	/*
987 	 * Convert remaining parameters of CREATE to form wanted by
988 	 * ProcedureCreate.
989 	 */
990 	interpret_function_parameter_list(pstate,
991 									  stmt->parameters,
992 									  languageOid,
993 									  false,	/* not an aggregate */
994 									  &parameterTypes,
995 									  &allParameterTypes,
996 									  &parameterModes,
997 									  &parameterNames,
998 									  &parameterDefaults,
999 									  &variadicArgType,
1000 									  &requiredResultType);
1001 
1002 	if (stmt->returnType)
1003 	{
1004 		/* explicit RETURNS clause */
1005 		compute_return_type(stmt->returnType, languageOid,
1006 							&prorettype, &returnsSet);
1007 		if (OidIsValid(requiredResultType) && prorettype != requiredResultType)
1008 			ereport(ERROR,
1009 					(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1010 					 errmsg("function result type must be %s because of OUT parameters",
1011 							format_type_be(requiredResultType))));
1012 	}
1013 	else if (OidIsValid(requiredResultType))
1014 	{
1015 		/* default RETURNS clause from OUT parameters */
1016 		prorettype = requiredResultType;
1017 		returnsSet = false;
1018 	}
1019 	else
1020 	{
1021 		ereport(ERROR,
1022 				(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
1023 				 errmsg("function result type must be specified")));
1024 		/* Alternative possibility: default to RETURNS VOID */
1025 		prorettype = VOIDOID;
1026 		returnsSet = false;
1027 	}
1028 
1029 	if (list_length(trftypes_list) > 0)
1030 	{
1031 		ListCell   *lc;
1032 		Datum	   *arr;
1033 		int			i;
1034 
1035 		arr = palloc(list_length(trftypes_list) * sizeof(Datum));
1036 		i = 0;
1037 		foreach(lc, trftypes_list)
1038 			arr[i++] = ObjectIdGetDatum(lfirst_oid(lc));
1039 		trftypes = construct_array(arr, list_length(trftypes_list),
1040 								   OIDOID, sizeof(Oid), true, 'i');
1041 	}
1042 	else
1043 	{
1044 		/* store SQL NULL instead of empty array */
1045 		trftypes = NULL;
1046 	}
1047 
1048 	compute_attributes_with_style(pstate, stmt->withClause, &isStrict, &volatility);
1049 
1050 	interpret_AS_clause(languageOid, language, funcname, as_clause,
1051 						&prosrc_str, &probin_str);
1052 
1053 	/*
1054 	 * Set default values for COST and ROWS depending on other parameters;
1055 	 * reject ROWS if it's not returnsSet.  NB: pg_dump knows these default
1056 	 * values, keep it in sync if you change them.
1057 	 */
1058 	if (procost < 0)
1059 	{
1060 		/* SQL and PL-language functions are assumed more expensive */
1061 		if (languageOid == INTERNALlanguageId ||
1062 			languageOid == ClanguageId)
1063 			procost = 1;
1064 		else
1065 			procost = 100;
1066 	}
1067 	if (prorows < 0)
1068 	{
1069 		if (returnsSet)
1070 			prorows = 1000;
1071 		else
1072 			prorows = 0;		/* dummy value if not returnsSet */
1073 	}
1074 	else if (!returnsSet)
1075 		ereport(ERROR,
1076 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1077 				 errmsg("ROWS is not applicable when function does not return a set")));
1078 
1079 	/*
1080 	 * And now that we have all the parameters, and know we're permitted to do
1081 	 * so, go ahead and create the function.
1082 	 */
1083 	return ProcedureCreate(funcname,
1084 						   namespaceId,
1085 						   stmt->replace,
1086 						   returnsSet,
1087 						   prorettype,
1088 						   GetUserId(),
1089 						   languageOid,
1090 						   languageValidator,
1091 						   prosrc_str,	/* converted to text later */
1092 						   probin_str,	/* converted to text later */
1093 						   false,	/* not an aggregate */
1094 						   isWindowFunc,
1095 						   security,
1096 						   isLeakProof,
1097 						   isStrict,
1098 						   volatility,
1099 						   parallel,
1100 						   parameterTypes,
1101 						   PointerGetDatum(allParameterTypes),
1102 						   PointerGetDatum(parameterModes),
1103 						   PointerGetDatum(parameterNames),
1104 						   parameterDefaults,
1105 						   PointerGetDatum(trftypes),
1106 						   PointerGetDatum(proconfig),
1107 						   procost,
1108 						   prorows);
1109 }
1110 
1111 /*
1112  * Guts of function deletion.
1113  *
1114  * Note: this is also used for aggregate deletion, since the OIDs of
1115  * both functions and aggregates point to pg_proc.
1116  */
1117 void
RemoveFunctionById(Oid funcOid)1118 RemoveFunctionById(Oid funcOid)
1119 {
1120 	Relation	relation;
1121 	HeapTuple	tup;
1122 	bool		isagg;
1123 
1124 	/*
1125 	 * Delete the pg_proc tuple.
1126 	 */
1127 	relation = heap_open(ProcedureRelationId, RowExclusiveLock);
1128 
1129 	tup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcOid));
1130 	if (!HeapTupleIsValid(tup)) /* should not happen */
1131 		elog(ERROR, "cache lookup failed for function %u", funcOid);
1132 
1133 	isagg = ((Form_pg_proc) GETSTRUCT(tup))->proisagg;
1134 
1135 	CatalogTupleDelete(relation, &tup->t_self);
1136 
1137 	ReleaseSysCache(tup);
1138 
1139 	heap_close(relation, RowExclusiveLock);
1140 
1141 	/*
1142 	 * If there's a pg_aggregate tuple, delete that too.
1143 	 */
1144 	if (isagg)
1145 	{
1146 		relation = heap_open(AggregateRelationId, RowExclusiveLock);
1147 
1148 		tup = SearchSysCache1(AGGFNOID, ObjectIdGetDatum(funcOid));
1149 		if (!HeapTupleIsValid(tup)) /* should not happen */
1150 			elog(ERROR, "cache lookup failed for pg_aggregate tuple for function %u", funcOid);
1151 
1152 		CatalogTupleDelete(relation, &tup->t_self);
1153 
1154 		ReleaseSysCache(tup);
1155 
1156 		heap_close(relation, RowExclusiveLock);
1157 	}
1158 }
1159 
1160 /*
1161  * Implements the ALTER FUNCTION utility command (except for the
1162  * RENAME and OWNER clauses, which are handled as part of the generic
1163  * ALTER framework).
1164  */
1165 ObjectAddress
AlterFunction(ParseState * pstate,AlterFunctionStmt * stmt)1166 AlterFunction(ParseState *pstate, AlterFunctionStmt *stmt)
1167 {
1168 	HeapTuple	tup;
1169 	Oid			funcOid;
1170 	Form_pg_proc procForm;
1171 	Relation	rel;
1172 	ListCell   *l;
1173 	DefElem    *volatility_item = NULL;
1174 	DefElem    *strict_item = NULL;
1175 	DefElem    *security_def_item = NULL;
1176 	DefElem    *leakproof_item = NULL;
1177 	List	   *set_items = NIL;
1178 	DefElem    *cost_item = NULL;
1179 	DefElem    *rows_item = NULL;
1180 	DefElem    *parallel_item = NULL;
1181 	ObjectAddress address;
1182 
1183 	rel = heap_open(ProcedureRelationId, RowExclusiveLock);
1184 
1185 	funcOid = LookupFuncWithArgs(stmt->func, false);
1186 
1187 	tup = SearchSysCacheCopy1(PROCOID, ObjectIdGetDatum(funcOid));
1188 	if (!HeapTupleIsValid(tup)) /* should not happen */
1189 		elog(ERROR, "cache lookup failed for function %u", funcOid);
1190 
1191 	procForm = (Form_pg_proc) GETSTRUCT(tup);
1192 
1193 	/* Permission check: must own function */
1194 	if (!pg_proc_ownercheck(funcOid, GetUserId()))
1195 		aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_PROC,
1196 					   NameListToString(stmt->func->objname));
1197 
1198 	if (procForm->proisagg)
1199 		ereport(ERROR,
1200 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1201 				 errmsg("\"%s\" is an aggregate function",
1202 						NameListToString(stmt->func->objname))));
1203 
1204 	/* Examine requested actions. */
1205 	foreach(l, stmt->actions)
1206 	{
1207 		DefElem    *defel = (DefElem *) lfirst(l);
1208 
1209 		if (compute_common_attribute(pstate,
1210 									 defel,
1211 									 &volatility_item,
1212 									 &strict_item,
1213 									 &security_def_item,
1214 									 &leakproof_item,
1215 									 &set_items,
1216 									 &cost_item,
1217 									 &rows_item,
1218 									 &parallel_item) == false)
1219 			elog(ERROR, "option \"%s\" not recognized", defel->defname);
1220 	}
1221 
1222 	if (volatility_item)
1223 		procForm->provolatile = interpret_func_volatility(volatility_item);
1224 	if (strict_item)
1225 		procForm->proisstrict = intVal(strict_item->arg);
1226 	if (security_def_item)
1227 		procForm->prosecdef = intVal(security_def_item->arg);
1228 	if (leakproof_item)
1229 	{
1230 		procForm->proleakproof = intVal(leakproof_item->arg);
1231 		if (procForm->proleakproof && !superuser())
1232 			ereport(ERROR,
1233 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
1234 					 errmsg("only superuser can define a leakproof function")));
1235 	}
1236 	if (cost_item)
1237 	{
1238 		procForm->procost = defGetNumeric(cost_item);
1239 		if (procForm->procost <= 0)
1240 			ereport(ERROR,
1241 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1242 					 errmsg("COST must be positive")));
1243 	}
1244 	if (rows_item)
1245 	{
1246 		procForm->prorows = defGetNumeric(rows_item);
1247 		if (procForm->prorows <= 0)
1248 			ereport(ERROR,
1249 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1250 					 errmsg("ROWS must be positive")));
1251 		if (!procForm->proretset)
1252 			ereport(ERROR,
1253 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
1254 					 errmsg("ROWS is not applicable when function does not return a set")));
1255 	}
1256 	if (set_items)
1257 	{
1258 		Datum		datum;
1259 		bool		isnull;
1260 		ArrayType  *a;
1261 		Datum		repl_val[Natts_pg_proc];
1262 		bool		repl_null[Natts_pg_proc];
1263 		bool		repl_repl[Natts_pg_proc];
1264 
1265 		/* extract existing proconfig setting */
1266 		datum = SysCacheGetAttr(PROCOID, tup, Anum_pg_proc_proconfig, &isnull);
1267 		a = isnull ? NULL : DatumGetArrayTypeP(datum);
1268 
1269 		/* update according to each SET or RESET item, left to right */
1270 		a = update_proconfig_value(a, set_items);
1271 
1272 		/* update the tuple */
1273 		memset(repl_repl, false, sizeof(repl_repl));
1274 		repl_repl[Anum_pg_proc_proconfig - 1] = true;
1275 
1276 		if (a == NULL)
1277 		{
1278 			repl_val[Anum_pg_proc_proconfig - 1] = (Datum) 0;
1279 			repl_null[Anum_pg_proc_proconfig - 1] = true;
1280 		}
1281 		else
1282 		{
1283 			repl_val[Anum_pg_proc_proconfig - 1] = PointerGetDatum(a);
1284 			repl_null[Anum_pg_proc_proconfig - 1] = false;
1285 		}
1286 
1287 		tup = heap_modify_tuple(tup, RelationGetDescr(rel),
1288 								repl_val, repl_null, repl_repl);
1289 	}
1290 	if (parallel_item)
1291 		procForm->proparallel = interpret_func_parallel(parallel_item);
1292 
1293 	/* Do the update */
1294 	CatalogTupleUpdate(rel, &tup->t_self, tup);
1295 
1296 	InvokeObjectPostAlterHook(ProcedureRelationId, funcOid, 0);
1297 
1298 	ObjectAddressSet(address, ProcedureRelationId, funcOid);
1299 
1300 	heap_close(rel, NoLock);
1301 	heap_freetuple(tup);
1302 
1303 	return address;
1304 }
1305 
1306 /*
1307  * SetFunctionReturnType - change declared return type of a function
1308  *
1309  * This is presently only used for adjusting legacy functions that return
1310  * OPAQUE to return whatever we find their correct definition should be.
1311  * The caller should emit a suitable warning explaining what we did.
1312  */
1313 void
SetFunctionReturnType(Oid funcOid,Oid newRetType)1314 SetFunctionReturnType(Oid funcOid, Oid newRetType)
1315 {
1316 	Relation	pg_proc_rel;
1317 	HeapTuple	tup;
1318 	Form_pg_proc procForm;
1319 	ObjectAddress func_address;
1320 	ObjectAddress type_address;
1321 
1322 	pg_proc_rel = heap_open(ProcedureRelationId, RowExclusiveLock);
1323 
1324 	tup = SearchSysCacheCopy1(PROCOID, ObjectIdGetDatum(funcOid));
1325 	if (!HeapTupleIsValid(tup)) /* should not happen */
1326 		elog(ERROR, "cache lookup failed for function %u", funcOid);
1327 	procForm = (Form_pg_proc) GETSTRUCT(tup);
1328 
1329 	if (procForm->prorettype != OPAQUEOID)	/* caller messed up */
1330 		elog(ERROR, "function %u doesn't return OPAQUE", funcOid);
1331 
1332 	/* okay to overwrite copied tuple */
1333 	procForm->prorettype = newRetType;
1334 
1335 	/* update the catalog and its indexes */
1336 	CatalogTupleUpdate(pg_proc_rel, &tup->t_self, tup);
1337 
1338 	heap_close(pg_proc_rel, RowExclusiveLock);
1339 
1340 	/*
1341 	 * Also update the dependency to the new type. Opaque is a pinned type, so
1342 	 * there is no old dependency record for it that we would need to remove.
1343 	 */
1344 	ObjectAddressSet(type_address, TypeRelationId, newRetType);
1345 	ObjectAddressSet(func_address, ProcedureRelationId, funcOid);
1346 	recordDependencyOn(&func_address, &type_address, DEPENDENCY_NORMAL);
1347 }
1348 
1349 
1350 /*
1351  * SetFunctionArgType - change declared argument type of a function
1352  *
1353  * As above, but change an argument's type.
1354  */
1355 void
SetFunctionArgType(Oid funcOid,int argIndex,Oid newArgType)1356 SetFunctionArgType(Oid funcOid, int argIndex, Oid newArgType)
1357 {
1358 	Relation	pg_proc_rel;
1359 	HeapTuple	tup;
1360 	Form_pg_proc procForm;
1361 	ObjectAddress func_address;
1362 	ObjectAddress type_address;
1363 
1364 	pg_proc_rel = heap_open(ProcedureRelationId, RowExclusiveLock);
1365 
1366 	tup = SearchSysCacheCopy1(PROCOID, ObjectIdGetDatum(funcOid));
1367 	if (!HeapTupleIsValid(tup)) /* should not happen */
1368 		elog(ERROR, "cache lookup failed for function %u", funcOid);
1369 	procForm = (Form_pg_proc) GETSTRUCT(tup);
1370 
1371 	if (argIndex < 0 || argIndex >= procForm->pronargs ||
1372 		procForm->proargtypes.values[argIndex] != OPAQUEOID)
1373 		elog(ERROR, "function %u doesn't take OPAQUE", funcOid);
1374 
1375 	/* okay to overwrite copied tuple */
1376 	procForm->proargtypes.values[argIndex] = newArgType;
1377 
1378 	/* update the catalog and its indexes */
1379 	CatalogTupleUpdate(pg_proc_rel, &tup->t_self, tup);
1380 
1381 	heap_close(pg_proc_rel, RowExclusiveLock);
1382 
1383 	/*
1384 	 * Also update the dependency to the new type. Opaque is a pinned type, so
1385 	 * there is no old dependency record for it that we would need to remove.
1386 	 */
1387 	ObjectAddressSet(type_address, TypeRelationId, newArgType);
1388 	ObjectAddressSet(func_address, ProcedureRelationId, funcOid);
1389 	recordDependencyOn(&func_address, &type_address, DEPENDENCY_NORMAL);
1390 }
1391 
1392 
1393 
1394 /*
1395  * CREATE CAST
1396  */
1397 ObjectAddress
CreateCast(CreateCastStmt * stmt)1398 CreateCast(CreateCastStmt *stmt)
1399 {
1400 	Oid			sourcetypeid;
1401 	Oid			targettypeid;
1402 	char		sourcetyptype;
1403 	char		targettyptype;
1404 	Oid			funcid;
1405 	Oid			castid;
1406 	int			nargs;
1407 	char		castcontext;
1408 	char		castmethod;
1409 	Relation	relation;
1410 	HeapTuple	tuple;
1411 	Datum		values[Natts_pg_cast];
1412 	bool		nulls[Natts_pg_cast];
1413 	ObjectAddress myself,
1414 				referenced;
1415 	AclResult	aclresult;
1416 
1417 	sourcetypeid = typenameTypeId(NULL, stmt->sourcetype);
1418 	targettypeid = typenameTypeId(NULL, stmt->targettype);
1419 	sourcetyptype = get_typtype(sourcetypeid);
1420 	targettyptype = get_typtype(targettypeid);
1421 
1422 	/* No pseudo-types allowed */
1423 	if (sourcetyptype == TYPTYPE_PSEUDO)
1424 		ereport(ERROR,
1425 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1426 				 errmsg("source data type %s is a pseudo-type",
1427 						TypeNameToString(stmt->sourcetype))));
1428 
1429 	if (targettyptype == TYPTYPE_PSEUDO)
1430 		ereport(ERROR,
1431 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1432 				 errmsg("target data type %s is a pseudo-type",
1433 						TypeNameToString(stmt->targettype))));
1434 
1435 	/* Permission check */
1436 	if (!pg_type_ownercheck(sourcetypeid, GetUserId())
1437 		&& !pg_type_ownercheck(targettypeid, GetUserId()))
1438 		ereport(ERROR,
1439 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
1440 				 errmsg("must be owner of type %s or type %s",
1441 						format_type_be(sourcetypeid),
1442 						format_type_be(targettypeid))));
1443 
1444 	aclresult = pg_type_aclcheck(sourcetypeid, GetUserId(), ACL_USAGE);
1445 	if (aclresult != ACLCHECK_OK)
1446 		aclcheck_error_type(aclresult, sourcetypeid);
1447 
1448 	aclresult = pg_type_aclcheck(targettypeid, GetUserId(), ACL_USAGE);
1449 	if (aclresult != ACLCHECK_OK)
1450 		aclcheck_error_type(aclresult, targettypeid);
1451 
1452 	/* Domains are allowed for historical reasons, but we warn */
1453 	if (sourcetyptype == TYPTYPE_DOMAIN)
1454 		ereport(WARNING,
1455 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1456 				 errmsg("cast will be ignored because the source data type is a domain")));
1457 
1458 	else if (targettyptype == TYPTYPE_DOMAIN)
1459 		ereport(WARNING,
1460 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1461 				 errmsg("cast will be ignored because the target data type is a domain")));
1462 
1463 	/* Determine the cast method */
1464 	if (stmt->func != NULL)
1465 		castmethod = COERCION_METHOD_FUNCTION;
1466 	else if (stmt->inout)
1467 		castmethod = COERCION_METHOD_INOUT;
1468 	else
1469 		castmethod = COERCION_METHOD_BINARY;
1470 
1471 	if (castmethod == COERCION_METHOD_FUNCTION)
1472 	{
1473 		Form_pg_proc procstruct;
1474 
1475 		funcid = LookupFuncWithArgs(stmt->func, false);
1476 
1477 		tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
1478 		if (!HeapTupleIsValid(tuple))
1479 			elog(ERROR, "cache lookup failed for function %u", funcid);
1480 
1481 		procstruct = (Form_pg_proc) GETSTRUCT(tuple);
1482 		nargs = procstruct->pronargs;
1483 		if (nargs < 1 || nargs > 3)
1484 			ereport(ERROR,
1485 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1486 					 errmsg("cast function must take one to three arguments")));
1487 		if (!IsBinaryCoercible(sourcetypeid, procstruct->proargtypes.values[0]))
1488 			ereport(ERROR,
1489 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1490 					 errmsg("argument of cast function must match or be binary-coercible from source data type")));
1491 		if (nargs > 1 && procstruct->proargtypes.values[1] != INT4OID)
1492 			ereport(ERROR,
1493 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1494 					 errmsg("second argument of cast function must be type %s",
1495 							"integer")));
1496 		if (nargs > 2 && procstruct->proargtypes.values[2] != BOOLOID)
1497 			ereport(ERROR,
1498 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1499 					 errmsg("third argument of cast function must be type %s",
1500 							"boolean")));
1501 		if (!IsBinaryCoercible(procstruct->prorettype, targettypeid))
1502 			ereport(ERROR,
1503 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1504 					 errmsg("return data type of cast function must match or be binary-coercible to target data type")));
1505 
1506 		/*
1507 		 * Restricting the volatility of a cast function may or may not be a
1508 		 * good idea in the abstract, but it definitely breaks many old
1509 		 * user-defined types.  Disable this check --- tgl 2/1/03
1510 		 */
1511 #ifdef NOT_USED
1512 		if (procstruct->provolatile == PROVOLATILE_VOLATILE)
1513 			ereport(ERROR,
1514 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1515 					 errmsg("cast function must not be volatile")));
1516 #endif
1517 		if (procstruct->proisagg)
1518 			ereport(ERROR,
1519 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1520 					 errmsg("cast function must not be an aggregate function")));
1521 		if (procstruct->proiswindow)
1522 			ereport(ERROR,
1523 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1524 					 errmsg("cast function must not be a window function")));
1525 		if (procstruct->proretset)
1526 			ereport(ERROR,
1527 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1528 					 errmsg("cast function must not return a set")));
1529 
1530 		ReleaseSysCache(tuple);
1531 	}
1532 	else
1533 	{
1534 		funcid = InvalidOid;
1535 		nargs = 0;
1536 	}
1537 
1538 	if (castmethod == COERCION_METHOD_BINARY)
1539 	{
1540 		int16		typ1len;
1541 		int16		typ2len;
1542 		bool		typ1byval;
1543 		bool		typ2byval;
1544 		char		typ1align;
1545 		char		typ2align;
1546 
1547 		/*
1548 		 * Must be superuser to create binary-compatible casts, since
1549 		 * erroneous casts can easily crash the backend.
1550 		 */
1551 		if (!superuser())
1552 			ereport(ERROR,
1553 					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
1554 					 errmsg("must be superuser to create a cast WITHOUT FUNCTION")));
1555 
1556 		/*
1557 		 * Also, insist that the types match as to size, alignment, and
1558 		 * pass-by-value attributes; this provides at least a crude check that
1559 		 * they have similar representations.  A pair of types that fail this
1560 		 * test should certainly not be equated.
1561 		 */
1562 		get_typlenbyvalalign(sourcetypeid, &typ1len, &typ1byval, &typ1align);
1563 		get_typlenbyvalalign(targettypeid, &typ2len, &typ2byval, &typ2align);
1564 		if (typ1len != typ2len ||
1565 			typ1byval != typ2byval ||
1566 			typ1align != typ2align)
1567 			ereport(ERROR,
1568 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1569 					 errmsg("source and target data types are not physically compatible")));
1570 
1571 		/*
1572 		 * We know that composite, enum and array types are never binary-
1573 		 * compatible with each other.  They all have OIDs embedded in them.
1574 		 *
1575 		 * Theoretically you could build a user-defined base type that is
1576 		 * binary-compatible with a composite, enum, or array type.  But we
1577 		 * disallow that too, as in practice such a cast is surely a mistake.
1578 		 * You can always work around that by writing a cast function.
1579 		 */
1580 		if (sourcetyptype == TYPTYPE_COMPOSITE ||
1581 			targettyptype == TYPTYPE_COMPOSITE)
1582 			ereport(ERROR,
1583 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1584 					 errmsg("composite data types are not binary-compatible")));
1585 
1586 		if (sourcetyptype == TYPTYPE_ENUM ||
1587 			targettyptype == TYPTYPE_ENUM)
1588 			ereport(ERROR,
1589 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1590 					 errmsg("enum data types are not binary-compatible")));
1591 
1592 		if (OidIsValid(get_element_type(sourcetypeid)) ||
1593 			OidIsValid(get_element_type(targettypeid)))
1594 			ereport(ERROR,
1595 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1596 					 errmsg("array data types are not binary-compatible")));
1597 
1598 		/*
1599 		 * We also disallow creating binary-compatibility casts involving
1600 		 * domains.  Casting from a domain to its base type is already
1601 		 * allowed, and casting the other way ought to go through domain
1602 		 * coercion to permit constraint checking.  Again, if you're intent on
1603 		 * having your own semantics for that, create a no-op cast function.
1604 		 *
1605 		 * NOTE: if we were to relax this, the above checks for composites
1606 		 * etc. would have to be modified to look through domains to their
1607 		 * base types.
1608 		 */
1609 		if (sourcetyptype == TYPTYPE_DOMAIN ||
1610 			targettyptype == TYPTYPE_DOMAIN)
1611 			ereport(ERROR,
1612 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1613 					 errmsg("domain data types must not be marked binary-compatible")));
1614 	}
1615 
1616 	/*
1617 	 * Allow source and target types to be same only for length coercion
1618 	 * functions.  We assume a multi-arg function does length coercion.
1619 	 */
1620 	if (sourcetypeid == targettypeid && nargs < 2)
1621 		ereport(ERROR,
1622 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1623 				 errmsg("source data type and target data type are the same")));
1624 
1625 	/* convert CoercionContext enum to char value for castcontext */
1626 	switch (stmt->context)
1627 	{
1628 		case COERCION_IMPLICIT:
1629 			castcontext = COERCION_CODE_IMPLICIT;
1630 			break;
1631 		case COERCION_ASSIGNMENT:
1632 			castcontext = COERCION_CODE_ASSIGNMENT;
1633 			break;
1634 		case COERCION_EXPLICIT:
1635 			castcontext = COERCION_CODE_EXPLICIT;
1636 			break;
1637 		default:
1638 			elog(ERROR, "unrecognized CoercionContext: %d", stmt->context);
1639 			castcontext = 0;	/* keep compiler quiet */
1640 			break;
1641 	}
1642 
1643 	relation = heap_open(CastRelationId, RowExclusiveLock);
1644 
1645 	/*
1646 	 * Check for duplicate.  This is just to give a friendly error message,
1647 	 * the unique index would catch it anyway (so no need to sweat about race
1648 	 * conditions).
1649 	 */
1650 	tuple = SearchSysCache2(CASTSOURCETARGET,
1651 							ObjectIdGetDatum(sourcetypeid),
1652 							ObjectIdGetDatum(targettypeid));
1653 	if (HeapTupleIsValid(tuple))
1654 		ereport(ERROR,
1655 				(errcode(ERRCODE_DUPLICATE_OBJECT),
1656 				 errmsg("cast from type %s to type %s already exists",
1657 						format_type_be(sourcetypeid),
1658 						format_type_be(targettypeid))));
1659 
1660 	/* ready to go */
1661 	values[Anum_pg_cast_castsource - 1] = ObjectIdGetDatum(sourcetypeid);
1662 	values[Anum_pg_cast_casttarget - 1] = ObjectIdGetDatum(targettypeid);
1663 	values[Anum_pg_cast_castfunc - 1] = ObjectIdGetDatum(funcid);
1664 	values[Anum_pg_cast_castcontext - 1] = CharGetDatum(castcontext);
1665 	values[Anum_pg_cast_castmethod - 1] = CharGetDatum(castmethod);
1666 
1667 	MemSet(nulls, false, sizeof(nulls));
1668 
1669 	tuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
1670 
1671 	castid = CatalogTupleInsert(relation, tuple);
1672 
1673 	/* make dependency entries */
1674 	myself.classId = CastRelationId;
1675 	myself.objectId = castid;
1676 	myself.objectSubId = 0;
1677 
1678 	/* dependency on source type */
1679 	referenced.classId = TypeRelationId;
1680 	referenced.objectId = sourcetypeid;
1681 	referenced.objectSubId = 0;
1682 	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1683 
1684 	/* dependency on target type */
1685 	referenced.classId = TypeRelationId;
1686 	referenced.objectId = targettypeid;
1687 	referenced.objectSubId = 0;
1688 	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1689 
1690 	/* dependency on function */
1691 	if (OidIsValid(funcid))
1692 	{
1693 		referenced.classId = ProcedureRelationId;
1694 		referenced.objectId = funcid;
1695 		referenced.objectSubId = 0;
1696 		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1697 	}
1698 
1699 	/* dependency on extension */
1700 	recordDependencyOnCurrentExtension(&myself, false);
1701 
1702 	/* Post creation hook for new cast */
1703 	InvokeObjectPostCreateHook(CastRelationId, castid, 0);
1704 
1705 	heap_freetuple(tuple);
1706 
1707 	heap_close(relation, RowExclusiveLock);
1708 
1709 	return myself;
1710 }
1711 
1712 /*
1713  * get_cast_oid - given two type OIDs, look up a cast OID
1714  *
1715  * If missing_ok is false, throw an error if the cast is not found.  If
1716  * true, just return InvalidOid.
1717  */
1718 Oid
get_cast_oid(Oid sourcetypeid,Oid targettypeid,bool missing_ok)1719 get_cast_oid(Oid sourcetypeid, Oid targettypeid, bool missing_ok)
1720 {
1721 	Oid			oid;
1722 
1723 	oid = GetSysCacheOid2(CASTSOURCETARGET,
1724 						  ObjectIdGetDatum(sourcetypeid),
1725 						  ObjectIdGetDatum(targettypeid));
1726 	if (!OidIsValid(oid) && !missing_ok)
1727 		ereport(ERROR,
1728 				(errcode(ERRCODE_UNDEFINED_OBJECT),
1729 				 errmsg("cast from type %s to type %s does not exist",
1730 						format_type_be(sourcetypeid),
1731 						format_type_be(targettypeid))));
1732 	return oid;
1733 }
1734 
1735 void
DropCastById(Oid castOid)1736 DropCastById(Oid castOid)
1737 {
1738 	Relation	relation;
1739 	ScanKeyData scankey;
1740 	SysScanDesc scan;
1741 	HeapTuple	tuple;
1742 
1743 	relation = heap_open(CastRelationId, RowExclusiveLock);
1744 
1745 	ScanKeyInit(&scankey,
1746 				ObjectIdAttributeNumber,
1747 				BTEqualStrategyNumber, F_OIDEQ,
1748 				ObjectIdGetDatum(castOid));
1749 	scan = systable_beginscan(relation, CastOidIndexId, true,
1750 							  NULL, 1, &scankey);
1751 
1752 	tuple = systable_getnext(scan);
1753 	if (!HeapTupleIsValid(tuple))
1754 		elog(ERROR, "could not find tuple for cast %u", castOid);
1755 	CatalogTupleDelete(relation, &tuple->t_self);
1756 
1757 	systable_endscan(scan);
1758 	heap_close(relation, RowExclusiveLock);
1759 }
1760 
1761 
1762 static void
check_transform_function(Form_pg_proc procstruct)1763 check_transform_function(Form_pg_proc procstruct)
1764 {
1765 	if (procstruct->provolatile == PROVOLATILE_VOLATILE)
1766 		ereport(ERROR,
1767 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1768 				 errmsg("transform function must not be volatile")));
1769 	if (procstruct->proisagg)
1770 		ereport(ERROR,
1771 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1772 				 errmsg("transform function must not be an aggregate function")));
1773 	if (procstruct->proiswindow)
1774 		ereport(ERROR,
1775 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1776 				 errmsg("transform function must not be a window function")));
1777 	if (procstruct->proretset)
1778 		ereport(ERROR,
1779 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1780 				 errmsg("transform function must not return a set")));
1781 	if (procstruct->pronargs != 1)
1782 		ereport(ERROR,
1783 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1784 				 errmsg("transform function must take one argument")));
1785 	if (procstruct->proargtypes.values[0] != INTERNALOID)
1786 		ereport(ERROR,
1787 				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1788 				 errmsg("first argument of transform function must be type %s",
1789 						"internal")));
1790 }
1791 
1792 
1793 /*
1794  * CREATE TRANSFORM
1795  */
1796 ObjectAddress
CreateTransform(CreateTransformStmt * stmt)1797 CreateTransform(CreateTransformStmt *stmt)
1798 {
1799 	Oid			typeid;
1800 	char		typtype;
1801 	Oid			langid;
1802 	Oid			fromsqlfuncid;
1803 	Oid			tosqlfuncid;
1804 	AclResult	aclresult;
1805 	Form_pg_proc procstruct;
1806 	Datum		values[Natts_pg_transform];
1807 	bool		nulls[Natts_pg_transform];
1808 	bool		replaces[Natts_pg_transform];
1809 	Oid			transformid;
1810 	HeapTuple	tuple;
1811 	HeapTuple	newtuple;
1812 	Relation	relation;
1813 	ObjectAddress myself,
1814 				referenced;
1815 	bool		is_replace;
1816 
1817 	/*
1818 	 * Get the type
1819 	 */
1820 	typeid = typenameTypeId(NULL, stmt->type_name);
1821 	typtype = get_typtype(typeid);
1822 
1823 	if (typtype == TYPTYPE_PSEUDO)
1824 		ereport(ERROR,
1825 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1826 				 errmsg("data type %s is a pseudo-type",
1827 						TypeNameToString(stmt->type_name))));
1828 
1829 	if (typtype == TYPTYPE_DOMAIN)
1830 		ereport(ERROR,
1831 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
1832 				 errmsg("data type %s is a domain",
1833 						TypeNameToString(stmt->type_name))));
1834 
1835 	if (!pg_type_ownercheck(typeid, GetUserId()))
1836 		aclcheck_error_type(ACLCHECK_NOT_OWNER, typeid);
1837 
1838 	aclresult = pg_type_aclcheck(typeid, GetUserId(), ACL_USAGE);
1839 	if (aclresult != ACLCHECK_OK)
1840 		aclcheck_error_type(aclresult, typeid);
1841 
1842 	/*
1843 	 * Get the language
1844 	 */
1845 	langid = get_language_oid(stmt->lang, false);
1846 
1847 	aclresult = pg_language_aclcheck(langid, GetUserId(), ACL_USAGE);
1848 	if (aclresult != ACLCHECK_OK)
1849 		aclcheck_error(aclresult, ACL_KIND_LANGUAGE, stmt->lang);
1850 
1851 	/*
1852 	 * Get the functions
1853 	 */
1854 	if (stmt->fromsql)
1855 	{
1856 		fromsqlfuncid = LookupFuncWithArgs(stmt->fromsql, false);
1857 
1858 		if (!pg_proc_ownercheck(fromsqlfuncid, GetUserId()))
1859 			aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_PROC, NameListToString(stmt->fromsql->objname));
1860 
1861 		aclresult = pg_proc_aclcheck(fromsqlfuncid, GetUserId(), ACL_EXECUTE);
1862 		if (aclresult != ACLCHECK_OK)
1863 			aclcheck_error(aclresult, ACL_KIND_PROC, NameListToString(stmt->fromsql->objname));
1864 
1865 		tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(fromsqlfuncid));
1866 		if (!HeapTupleIsValid(tuple))
1867 			elog(ERROR, "cache lookup failed for function %u", fromsqlfuncid);
1868 		procstruct = (Form_pg_proc) GETSTRUCT(tuple);
1869 		if (procstruct->prorettype != INTERNALOID)
1870 			ereport(ERROR,
1871 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1872 					 errmsg("return data type of FROM SQL function must be %s",
1873 							"internal")));
1874 		check_transform_function(procstruct);
1875 		ReleaseSysCache(tuple);
1876 	}
1877 	else
1878 		fromsqlfuncid = InvalidOid;
1879 
1880 	if (stmt->tosql)
1881 	{
1882 		tosqlfuncid = LookupFuncWithArgs(stmt->tosql, false);
1883 
1884 		if (!pg_proc_ownercheck(tosqlfuncid, GetUserId()))
1885 			aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_PROC, NameListToString(stmt->tosql->objname));
1886 
1887 		aclresult = pg_proc_aclcheck(tosqlfuncid, GetUserId(), ACL_EXECUTE);
1888 		if (aclresult != ACLCHECK_OK)
1889 			aclcheck_error(aclresult, ACL_KIND_PROC, NameListToString(stmt->tosql->objname));
1890 
1891 		tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(tosqlfuncid));
1892 		if (!HeapTupleIsValid(tuple))
1893 			elog(ERROR, "cache lookup failed for function %u", tosqlfuncid);
1894 		procstruct = (Form_pg_proc) GETSTRUCT(tuple);
1895 		if (procstruct->prorettype != typeid)
1896 			ereport(ERROR,
1897 					(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
1898 					 errmsg("return data type of TO SQL function must be the transform data type")));
1899 		check_transform_function(procstruct);
1900 		ReleaseSysCache(tuple);
1901 	}
1902 	else
1903 		tosqlfuncid = InvalidOid;
1904 
1905 	/*
1906 	 * Ready to go
1907 	 */
1908 	values[Anum_pg_transform_trftype - 1] = ObjectIdGetDatum(typeid);
1909 	values[Anum_pg_transform_trflang - 1] = ObjectIdGetDatum(langid);
1910 	values[Anum_pg_transform_trffromsql - 1] = ObjectIdGetDatum(fromsqlfuncid);
1911 	values[Anum_pg_transform_trftosql - 1] = ObjectIdGetDatum(tosqlfuncid);
1912 
1913 	MemSet(nulls, false, sizeof(nulls));
1914 
1915 	relation = heap_open(TransformRelationId, RowExclusiveLock);
1916 
1917 	tuple = SearchSysCache2(TRFTYPELANG,
1918 							ObjectIdGetDatum(typeid),
1919 							ObjectIdGetDatum(langid));
1920 	if (HeapTupleIsValid(tuple))
1921 	{
1922 		if (!stmt->replace)
1923 			ereport(ERROR,
1924 					(errcode(ERRCODE_DUPLICATE_OBJECT),
1925 					 errmsg("transform for type %s language \"%s\" already exists",
1926 							format_type_be(typeid),
1927 							stmt->lang)));
1928 
1929 		MemSet(replaces, false, sizeof(replaces));
1930 		replaces[Anum_pg_transform_trffromsql - 1] = true;
1931 		replaces[Anum_pg_transform_trftosql - 1] = true;
1932 
1933 		newtuple = heap_modify_tuple(tuple, RelationGetDescr(relation), values, nulls, replaces);
1934 		CatalogTupleUpdate(relation, &newtuple->t_self, newtuple);
1935 
1936 		transformid = HeapTupleGetOid(tuple);
1937 		ReleaseSysCache(tuple);
1938 		is_replace = true;
1939 	}
1940 	else
1941 	{
1942 		newtuple = heap_form_tuple(RelationGetDescr(relation), values, nulls);
1943 		transformid = CatalogTupleInsert(relation, newtuple);
1944 		is_replace = false;
1945 	}
1946 
1947 	if (is_replace)
1948 		deleteDependencyRecordsFor(TransformRelationId, transformid, true);
1949 
1950 	/* make dependency entries */
1951 	myself.classId = TransformRelationId;
1952 	myself.objectId = transformid;
1953 	myself.objectSubId = 0;
1954 
1955 	/* dependency on language */
1956 	referenced.classId = LanguageRelationId;
1957 	referenced.objectId = langid;
1958 	referenced.objectSubId = 0;
1959 	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1960 
1961 	/* dependency on type */
1962 	referenced.classId = TypeRelationId;
1963 	referenced.objectId = typeid;
1964 	referenced.objectSubId = 0;
1965 	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1966 
1967 	/* dependencies on functions */
1968 	if (OidIsValid(fromsqlfuncid))
1969 	{
1970 		referenced.classId = ProcedureRelationId;
1971 		referenced.objectId = fromsqlfuncid;
1972 		referenced.objectSubId = 0;
1973 		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1974 	}
1975 	if (OidIsValid(tosqlfuncid))
1976 	{
1977 		referenced.classId = ProcedureRelationId;
1978 		referenced.objectId = tosqlfuncid;
1979 		referenced.objectSubId = 0;
1980 		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
1981 	}
1982 
1983 	/* dependency on extension */
1984 	recordDependencyOnCurrentExtension(&myself, is_replace);
1985 
1986 	/* Post creation hook for new transform */
1987 	InvokeObjectPostCreateHook(TransformRelationId, transformid, 0);
1988 
1989 	heap_freetuple(newtuple);
1990 
1991 	heap_close(relation, RowExclusiveLock);
1992 
1993 	return myself;
1994 }
1995 
1996 
1997 /*
1998  * get_transform_oid - given type OID and language OID, look up a transform OID
1999  *
2000  * If missing_ok is false, throw an error if the transform is not found.  If
2001  * true, just return InvalidOid.
2002  */
2003 Oid
get_transform_oid(Oid type_id,Oid lang_id,bool missing_ok)2004 get_transform_oid(Oid type_id, Oid lang_id, bool missing_ok)
2005 {
2006 	Oid			oid;
2007 
2008 	oid = GetSysCacheOid2(TRFTYPELANG,
2009 						  ObjectIdGetDatum(type_id),
2010 						  ObjectIdGetDatum(lang_id));
2011 	if (!OidIsValid(oid) && !missing_ok)
2012 		ereport(ERROR,
2013 				(errcode(ERRCODE_UNDEFINED_OBJECT),
2014 				 errmsg("transform for type %s language \"%s\" does not exist",
2015 						format_type_be(type_id),
2016 						get_language_name(lang_id, false))));
2017 	return oid;
2018 }
2019 
2020 
2021 void
DropTransformById(Oid transformOid)2022 DropTransformById(Oid transformOid)
2023 {
2024 	Relation	relation;
2025 	ScanKeyData scankey;
2026 	SysScanDesc scan;
2027 	HeapTuple	tuple;
2028 
2029 	relation = heap_open(TransformRelationId, RowExclusiveLock);
2030 
2031 	ScanKeyInit(&scankey,
2032 				ObjectIdAttributeNumber,
2033 				BTEqualStrategyNumber, F_OIDEQ,
2034 				ObjectIdGetDatum(transformOid));
2035 	scan = systable_beginscan(relation, TransformOidIndexId, true,
2036 							  NULL, 1, &scankey);
2037 
2038 	tuple = systable_getnext(scan);
2039 	if (!HeapTupleIsValid(tuple))
2040 		elog(ERROR, "could not find tuple for transform %u", transformOid);
2041 	CatalogTupleDelete(relation, &tuple->t_self);
2042 
2043 	systable_endscan(scan);
2044 	heap_close(relation, RowExclusiveLock);
2045 }
2046 
2047 
2048 /*
2049  * Subroutine for ALTER FUNCTION/AGGREGATE SET SCHEMA/RENAME
2050  *
2051  * Is there a function with the given name and signature already in the given
2052  * namespace?  If so, raise an appropriate error message.
2053  */
2054 void
IsThereFunctionInNamespace(const char * proname,int pronargs,oidvector * proargtypes,Oid nspOid)2055 IsThereFunctionInNamespace(const char *proname, int pronargs,
2056 						   oidvector *proargtypes, Oid nspOid)
2057 {
2058 	/* check for duplicate name (more friendly than unique-index failure) */
2059 	if (SearchSysCacheExists3(PROCNAMEARGSNSP,
2060 							  CStringGetDatum(proname),
2061 							  PointerGetDatum(proargtypes),
2062 							  ObjectIdGetDatum(nspOid)))
2063 		ereport(ERROR,
2064 				(errcode(ERRCODE_DUPLICATE_FUNCTION),
2065 				 errmsg("function %s already exists in schema \"%s\"",
2066 						funcname_signature_string(proname, pronargs,
2067 												  NIL, proargtypes->values),
2068 						get_namespace_name(nspOid))));
2069 }
2070 
2071 /*
2072  * ExecuteDoStmt
2073  *		Execute inline procedural-language code
2074  */
2075 void
ExecuteDoStmt(DoStmt * stmt)2076 ExecuteDoStmt(DoStmt *stmt)
2077 {
2078 	InlineCodeBlock *codeblock = makeNode(InlineCodeBlock);
2079 	ListCell   *arg;
2080 	DefElem    *as_item = NULL;
2081 	DefElem    *language_item = NULL;
2082 	char	   *language;
2083 	Oid			laninline;
2084 	HeapTuple	languageTuple;
2085 	Form_pg_language languageStruct;
2086 
2087 	/* Process options we got from gram.y */
2088 	foreach(arg, stmt->args)
2089 	{
2090 		DefElem    *defel = (DefElem *) lfirst(arg);
2091 
2092 		if (strcmp(defel->defname, "as") == 0)
2093 		{
2094 			if (as_item)
2095 				ereport(ERROR,
2096 						(errcode(ERRCODE_SYNTAX_ERROR),
2097 						 errmsg("conflicting or redundant options")));
2098 			as_item = defel;
2099 		}
2100 		else if (strcmp(defel->defname, "language") == 0)
2101 		{
2102 			if (language_item)
2103 				ereport(ERROR,
2104 						(errcode(ERRCODE_SYNTAX_ERROR),
2105 						 errmsg("conflicting or redundant options")));
2106 			language_item = defel;
2107 		}
2108 		else
2109 			elog(ERROR, "option \"%s\" not recognized",
2110 				 defel->defname);
2111 	}
2112 
2113 	if (as_item)
2114 		codeblock->source_text = strVal(as_item->arg);
2115 	else
2116 		ereport(ERROR,
2117 				(errcode(ERRCODE_SYNTAX_ERROR),
2118 				 errmsg("no inline code specified")));
2119 
2120 	/* if LANGUAGE option wasn't specified, use the default */
2121 	if (language_item)
2122 		language = strVal(language_item->arg);
2123 	else
2124 		language = "plpgsql";
2125 
2126 	/* Look up the language and validate permissions */
2127 	languageTuple = SearchSysCache1(LANGNAME, PointerGetDatum(language));
2128 	if (!HeapTupleIsValid(languageTuple))
2129 		ereport(ERROR,
2130 				(errcode(ERRCODE_UNDEFINED_OBJECT),
2131 				 errmsg("language \"%s\" does not exist", language),
2132 				 (PLTemplateExists(language) ?
2133 				  errhint("Use CREATE LANGUAGE to load the language into the database.") : 0)));
2134 
2135 	codeblock->langOid = HeapTupleGetOid(languageTuple);
2136 	languageStruct = (Form_pg_language) GETSTRUCT(languageTuple);
2137 	codeblock->langIsTrusted = languageStruct->lanpltrusted;
2138 
2139 	if (languageStruct->lanpltrusted)
2140 	{
2141 		/* if trusted language, need USAGE privilege */
2142 		AclResult	aclresult;
2143 
2144 		aclresult = pg_language_aclcheck(codeblock->langOid, GetUserId(),
2145 										 ACL_USAGE);
2146 		if (aclresult != ACLCHECK_OK)
2147 			aclcheck_error(aclresult, ACL_KIND_LANGUAGE,
2148 						   NameStr(languageStruct->lanname));
2149 	}
2150 	else
2151 	{
2152 		/* if untrusted language, must be superuser */
2153 		if (!superuser())
2154 			aclcheck_error(ACLCHECK_NO_PRIV, ACL_KIND_LANGUAGE,
2155 						   NameStr(languageStruct->lanname));
2156 	}
2157 
2158 	/* get the handler function's OID */
2159 	laninline = languageStruct->laninline;
2160 	if (!OidIsValid(laninline))
2161 		ereport(ERROR,
2162 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
2163 				 errmsg("language \"%s\" does not support inline code execution",
2164 						NameStr(languageStruct->lanname))));
2165 
2166 	ReleaseSysCache(languageTuple);
2167 
2168 	/* execute the inline handler */
2169 	OidFunctionCall1(laninline, PointerGetDatum(codeblock));
2170 }
2171