codekingpro/portable-devtools

1/*-------------------------------------------------------------------------2 *3 * fmgr.h4 *	  Definitions for the Postgres function manager and function-call5 *	  interface.6 *7 * This file must be included by all Postgres modules that either define8 * or call fmgr-callable functions.9 *10 *11 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group12 * Portions Copyright (c) 1994, Regents of the University of California13 *14 * src/include/fmgr.h15 *16 *-------------------------------------------------------------------------17 */18#ifndef FMGR_H19#define FMGR_H20 21/* We don't want to include primnodes.h here, so make some stub references */22typedef struct Node *fmNodePtr;23typedef struct Aggref *fmAggrefPtr;24 25/* Likewise, avoid including execnodes.h here */26typedef void (*fmExprContextCallbackFunction) (Datum arg);27 28/* Likewise, avoid including stringinfo.h here */29typedef struct StringInfoData *fmStringInfo;30 31 32/*33 * All functions that can be called directly by fmgr must have this signature.34 * (Other functions can be called by using a handler that does have this35 * signature.)36 */37 38typedef struct FunctionCallInfoBaseData *FunctionCallInfo;39 40typedef Datum (*PGFunction) (FunctionCallInfo fcinfo);41 42/*43 * This struct holds the system-catalog information that must be looked up44 * before a function can be called through fmgr.  If the same function is45 * to be called multiple times, the lookup need be done only once and the46 * info struct saved for re-use.47 *48 * Note that fn_expr really is parse-time-determined information about the49 * arguments, rather than about the function itself.  But it's convenient to50 * store it here rather than in FunctionCallInfoBaseData, where it might more51 * logically belong.52 *53 * fn_extra is available for use by the called function; all other fields54 * should be treated as read-only after the struct is created.55 */56typedef struct FmgrInfo57{58	PGFunction	fn_addr;		/* pointer to function or handler to be called */59	Oid			fn_oid;			/* OID of function (NOT of handler, if any) */60	short		fn_nargs;		/* number of input args (0..FUNC_MAX_ARGS) */61	bool		fn_strict;		/* function is "strict" (NULL in => NULL out) */62	bool		fn_retset;		/* function returns a set */63	unsigned char fn_stats;		/* collect stats if track_functions > this */64	void	   *fn_extra;		/* extra space for use by handler */65	MemoryContext fn_mcxt;		/* memory context to store fn_extra in */66	fmNodePtr	fn_expr;		/* expression parse tree for call, or NULL */67} FmgrInfo;68 69/*70 * This struct is the data actually passed to an fmgr-called function.71 *72 * The called function is expected to set isnull, and possibly resultinfo or73 * fields in whatever resultinfo points to.  It should not change any other74 * fields.  (In particular, scribbling on the argument arrays is a bad idea,75 * since some callers assume they can re-call with the same arguments.)76 *77 * Note that enough space for arguments needs to be provided, either by using78 * SizeForFunctionCallInfo() in dynamic allocations, or by using79 * LOCAL_FCINFO() for on-stack allocations.80 *81 * This struct is named *BaseData, rather than *Data, to break pre v12 code82 * that allocated FunctionCallInfoData itself, as it'd often silently break83 * old code due to no space for arguments being provided.84 */85typedef struct FunctionCallInfoBaseData86{87	FmgrInfo   *flinfo;			/* ptr to lookup info used for this call */88	fmNodePtr	context;		/* pass info about context of call */89	fmNodePtr	resultinfo;		/* pass or return extra info about result */90	Oid			fncollation;	/* collation for function to use */91#define FIELDNO_FUNCTIONCALLINFODATA_ISNULL 492	bool		isnull;			/* function must set true if result is NULL */93	short		nargs;			/* # arguments actually passed */94#define FIELDNO_FUNCTIONCALLINFODATA_ARGS 695	NullableDatum args[FLEXIBLE_ARRAY_MEMBER];96} FunctionCallInfoBaseData;97 98/*99 * Space needed for a FunctionCallInfoBaseData struct with sufficient space100 * for `nargs` arguments.101 */102#define SizeForFunctionCallInfo(nargs) \103	(offsetof(FunctionCallInfoBaseData, args) + \104	 sizeof(NullableDatum) * (nargs))105 106/*107 * This macro ensures that `name` points to a stack-allocated108 * FunctionCallInfoBaseData struct with sufficient space for `nargs` arguments.109 */110#define LOCAL_FCINFO(name, nargs) \111	/* use union with FunctionCallInfoBaseData to guarantee alignment */ \112	union \113	{ \114		FunctionCallInfoBaseData fcinfo; \115		/* ensure enough space for nargs args is available */ \116		char fcinfo_data[SizeForFunctionCallInfo(nargs)]; \117	} name##data; \118	FunctionCallInfo name = &name##data.fcinfo119 120/*121 * This routine fills a FmgrInfo struct, given the OID122 * of the function to be called.123 */124extern void fmgr_info(Oid functionId, FmgrInfo *finfo);125 126/*127 * Same, when the FmgrInfo struct is in a memory context longer-lived than128 * CurrentMemoryContext.  The specified context will be set as fn_mcxt129 * and used to hold all subsidiary data of finfo.130 */131extern void fmgr_info_cxt(Oid functionId, FmgrInfo *finfo,132						  MemoryContext mcxt);133 134/* Convenience macro for setting the fn_expr field */135#define fmgr_info_set_expr(expr, finfo) \136	((finfo)->fn_expr = (expr))137 138/*139 * Copy an FmgrInfo struct140 */141extern void fmgr_info_copy(FmgrInfo *dstinfo, FmgrInfo *srcinfo,142						   MemoryContext destcxt);143 144extern void fmgr_symbol(Oid functionId, char **mod, char **fn);145 146/*147 * This macro initializes all the fields of a FunctionCallInfoBaseData except148 * for the args[] array.149 */150#define InitFunctionCallInfoData(Fcinfo, Flinfo, Nargs, Collation, Context, Resultinfo) \151	do { \152		(Fcinfo).flinfo = (Flinfo); \153		(Fcinfo).context = (Context); \154		(Fcinfo).resultinfo = (Resultinfo); \155		(Fcinfo).fncollation = (Collation); \156		(Fcinfo).isnull = false; \157		(Fcinfo).nargs = (Nargs); \158	} while (0)159 160/*161 * This macro invokes a function given a filled-in FunctionCallInfoBaseData162 * struct.  The macro result is the returned Datum --- but note that163 * caller must still check fcinfo->isnull!	Also, if function is strict,164 * it is caller's responsibility to verify that no null arguments are present165 * before calling.166 *167 * Some code performs multiple calls without redoing InitFunctionCallInfoData,168 * possibly altering the argument values.  This is okay, but be sure to reset169 * the fcinfo->isnull flag before each call, since callees are permitted to170 * assume that starts out false.171 */172#define FunctionCallInvoke(fcinfo)	((* (fcinfo)->flinfo->fn_addr) (fcinfo))173 174 175/*-------------------------------------------------------------------------176 *		Support macros to ease writing fmgr-compatible functions177 *178 * A C-coded fmgr-compatible function should be declared as179 *180 *		Datum181 *		function_name(PG_FUNCTION_ARGS)182 *		{183 *			...184 *		}185 *186 * It should access its arguments using appropriate PG_GETARG_xxx macros187 * and should return its result using PG_RETURN_xxx.188 *189 *-------------------------------------------------------------------------190 */191 192/* Standard parameter list for fmgr-compatible functions */193#define PG_FUNCTION_ARGS	FunctionCallInfo fcinfo194 195/*196 * Get collation function should use.197 */198#define PG_GET_COLLATION()	(fcinfo->fncollation)199 200/*201 * Get number of arguments passed to function.202 */203#define PG_NARGS() (fcinfo->nargs)204 205/*206 * If function is not marked "proisstrict" in pg_proc, it must check for207 * null arguments using this macro.  Do not try to GETARG a null argument!208 */209#define PG_ARGISNULL(n)  (fcinfo->args[n].isnull)210 211/*212 * Support for fetching detoasted copies of toastable datatypes (all of213 * which are varlena types).  pg_detoast_datum() gives you either the input214 * datum (if not toasted) or a detoasted copy allocated with palloc().215 * pg_detoast_datum_copy() always gives you a palloc'd copy --- use it216 * if you need a modifiable copy of the input.  Caller is expected to have217 * checked for null inputs first, if necessary.218 *219 * pg_detoast_datum_packed() will return packed (1-byte header) datums220 * unmodified.  It will still expand an externally toasted or compressed datum.221 * The resulting datum can be accessed using VARSIZE_ANY() and VARDATA_ANY()222 * (beware of multiple evaluations in those macros!)223 *224 * In consumers oblivious to data alignment, call PG_DETOAST_DATUM_PACKED(),225 * VARDATA_ANY(), VARSIZE_ANY() and VARSIZE_ANY_EXHDR().  Elsewhere, call226 * PG_DETOAST_DATUM(), VARDATA() and VARSIZE().  Directly fetching an int16,227 * int32 or wider field in the struct representing the datum layout requires228 * aligned data.  memcpy() is alignment-oblivious, as are most operations on229 * datatypes, such as text, whose layout struct contains only char fields.230 *231 * Note: it'd be nice if these could be macros, but I see no way to do that232 * without evaluating the arguments multiple times, which is NOT acceptable.233 */234extern struct varlena *pg_detoast_datum(struct varlena *datum);235extern struct varlena *pg_detoast_datum_copy(struct varlena *datum);236extern struct varlena *pg_detoast_datum_slice(struct varlena *datum,237											  int32 first, int32 count);238extern struct varlena *pg_detoast_datum_packed(struct varlena *datum);239 240#define PG_DETOAST_DATUM(datum) \241	pg_detoast_datum((struct varlena *) DatumGetPointer(datum))242#define PG_DETOAST_DATUM_COPY(datum) \243	pg_detoast_datum_copy((struct varlena *) DatumGetPointer(datum))244#define PG_DETOAST_DATUM_SLICE(datum,f,c) \245		pg_detoast_datum_slice((struct varlena *) DatumGetPointer(datum), \246		(int32) (f), (int32) (c))247/* WARNING -- unaligned pointer */248#define PG_DETOAST_DATUM_PACKED(datum) \249	pg_detoast_datum_packed((struct varlena *) DatumGetPointer(datum))250 251/*252 * Support for cleaning up detoasted copies of inputs.  This must only253 * be used for pass-by-ref datatypes, and normally would only be used254 * for toastable types.  If the given pointer is different from the255 * original argument, assume it's a palloc'd detoasted copy, and pfree it.256 * NOTE: most functions on toastable types do not have to worry about this,257 * but we currently require that support functions for indexes not leak258 * memory.259 */260#define PG_FREE_IF_COPY(ptr,n) \261	do { \262		if ((Pointer) (ptr) != PG_GETARG_POINTER(n)) \263			pfree(ptr); \264	} while (0)265 266/* Macros for fetching arguments of standard types */267 268#define PG_GETARG_DATUM(n)	 (fcinfo->args[n].value)269#define PG_GETARG_INT32(n)	 DatumGetInt32(PG_GETARG_DATUM(n))270#define PG_GETARG_UINT32(n)  DatumGetUInt32(PG_GETARG_DATUM(n))271#define PG_GETARG_INT16(n)	 DatumGetInt16(PG_GETARG_DATUM(n))272#define PG_GETARG_UINT16(n)  DatumGetUInt16(PG_GETARG_DATUM(n))273#define PG_GETARG_CHAR(n)	 DatumGetChar(PG_GETARG_DATUM(n))274#define PG_GETARG_BOOL(n)	 DatumGetBool(PG_GETARG_DATUM(n))275#define PG_GETARG_OID(n)	 DatumGetObjectId(PG_GETARG_DATUM(n))276#define PG_GETARG_POINTER(n) DatumGetPointer(PG_GETARG_DATUM(n))277#define PG_GETARG_CSTRING(n) DatumGetCString(PG_GETARG_DATUM(n))278#define PG_GETARG_NAME(n)	 DatumGetName(PG_GETARG_DATUM(n))279#define PG_GETARG_TRANSACTIONID(n)	DatumGetTransactionId(PG_GETARG_DATUM(n))280/* these macros hide the pass-by-reference-ness of the datatype: */281#define PG_GETARG_FLOAT4(n)  DatumGetFloat4(PG_GETARG_DATUM(n))282#define PG_GETARG_FLOAT8(n)  DatumGetFloat8(PG_GETARG_DATUM(n))283#define PG_GETARG_INT64(n)	 DatumGetInt64(PG_GETARG_DATUM(n))284/* use this if you want the raw, possibly-toasted input datum: */285#define PG_GETARG_RAW_VARLENA_P(n)	((struct varlena *) PG_GETARG_POINTER(n))286/* use this if you want the input datum de-toasted: */287#define PG_GETARG_VARLENA_P(n) PG_DETOAST_DATUM(PG_GETARG_DATUM(n))288/* and this if you can handle 1-byte-header datums: */289#define PG_GETARG_VARLENA_PP(n) PG_DETOAST_DATUM_PACKED(PG_GETARG_DATUM(n))290/* DatumGetFoo macros for varlena types will typically look like this: */291#define DatumGetByteaPP(X)			((bytea *) PG_DETOAST_DATUM_PACKED(X))292#define DatumGetTextPP(X)			((text *) PG_DETOAST_DATUM_PACKED(X))293#define DatumGetBpCharPP(X)			((BpChar *) PG_DETOAST_DATUM_PACKED(X))294#define DatumGetVarCharPP(X)		((VarChar *) PG_DETOAST_DATUM_PACKED(X))295#define DatumGetHeapTupleHeader(X)	((HeapTupleHeader) PG_DETOAST_DATUM(X))296/* And we also offer variants that return an OK-to-write copy */297#define DatumGetByteaPCopy(X)		((bytea *) PG_DETOAST_DATUM_COPY(X))298#define DatumGetTextPCopy(X)		((text *) PG_DETOAST_DATUM_COPY(X))299#define DatumGetBpCharPCopy(X)		((BpChar *) PG_DETOAST_DATUM_COPY(X))300#define DatumGetVarCharPCopy(X)		((VarChar *) PG_DETOAST_DATUM_COPY(X))301#define DatumGetHeapTupleHeaderCopy(X)	((HeapTupleHeader) PG_DETOAST_DATUM_COPY(X))302/* Variants which return n bytes starting at pos. m */303#define DatumGetByteaPSlice(X,m,n)	((bytea *) PG_DETOAST_DATUM_SLICE(X,m,n))304#define DatumGetTextPSlice(X,m,n)	((text *) PG_DETOAST_DATUM_SLICE(X,m,n))305#define DatumGetBpCharPSlice(X,m,n) ((BpChar *) PG_DETOAST_DATUM_SLICE(X,m,n))306#define DatumGetVarCharPSlice(X,m,n) ((VarChar *) PG_DETOAST_DATUM_SLICE(X,m,n))307/* GETARG macros for varlena types will typically look like this: */308#define PG_GETARG_BYTEA_PP(n)		DatumGetByteaPP(PG_GETARG_DATUM(n))309#define PG_GETARG_TEXT_PP(n)		DatumGetTextPP(PG_GETARG_DATUM(n))310#define PG_GETARG_BPCHAR_PP(n)		DatumGetBpCharPP(PG_GETARG_DATUM(n))311#define PG_GETARG_VARCHAR_PP(n)		DatumGetVarCharPP(PG_GETARG_DATUM(n))312#define PG_GETARG_HEAPTUPLEHEADER(n)	DatumGetHeapTupleHeader(PG_GETARG_DATUM(n))313/* And we also offer variants that return an OK-to-write copy */314#define PG_GETARG_BYTEA_P_COPY(n)	DatumGetByteaPCopy(PG_GETARG_DATUM(n))315#define PG_GETARG_TEXT_P_COPY(n)	DatumGetTextPCopy(PG_GETARG_DATUM(n))316#define PG_GETARG_BPCHAR_P_COPY(n)	DatumGetBpCharPCopy(PG_GETARG_DATUM(n))317#define PG_GETARG_VARCHAR_P_COPY(n) DatumGetVarCharPCopy(PG_GETARG_DATUM(n))318#define PG_GETARG_HEAPTUPLEHEADER_COPY(n)	DatumGetHeapTupleHeaderCopy(PG_GETARG_DATUM(n))319/* And a b-byte slice from position a -also OK to write */320#define PG_GETARG_BYTEA_P_SLICE(n,a,b) DatumGetByteaPSlice(PG_GETARG_DATUM(n),a,b)321#define PG_GETARG_TEXT_P_SLICE(n,a,b)  DatumGetTextPSlice(PG_GETARG_DATUM(n),a,b)322#define PG_GETARG_BPCHAR_P_SLICE(n,a,b) DatumGetBpCharPSlice(PG_GETARG_DATUM(n),a,b)323#define PG_GETARG_VARCHAR_P_SLICE(n,a,b) DatumGetVarCharPSlice(PG_GETARG_DATUM(n),a,b)324/*325 * Obsolescent variants that guarantee INT alignment for the return value.326 * Few operations on these particular types need alignment, mainly operations327 * that cast the VARDATA pointer to a type like int16[].  Most code should use328 * the ...PP(X) counterpart.  Nonetheless, these appear frequently in code329 * predating the PostgreSQL 8.3 introduction of the ...PP(X) variants.330 */331#define DatumGetByteaP(X)			((bytea *) PG_DETOAST_DATUM(X))332#define DatumGetTextP(X)			((text *) PG_DETOAST_DATUM(X))333#define DatumGetBpCharP(X)			((BpChar *) PG_DETOAST_DATUM(X))334#define DatumGetVarCharP(X)			((VarChar *) PG_DETOAST_DATUM(X))335#define PG_GETARG_BYTEA_P(n)		DatumGetByteaP(PG_GETARG_DATUM(n))336#define PG_GETARG_TEXT_P(n)			DatumGetTextP(PG_GETARG_DATUM(n))337#define PG_GETARG_BPCHAR_P(n)		DatumGetBpCharP(PG_GETARG_DATUM(n))338#define PG_GETARG_VARCHAR_P(n)		DatumGetVarCharP(PG_GETARG_DATUM(n))339 340/* To access options from opclass support functions use this: */341#define PG_HAS_OPCLASS_OPTIONS()	has_fn_opclass_options(fcinfo->flinfo)342#define PG_GET_OPCLASS_OPTIONS()	get_fn_opclass_options(fcinfo->flinfo)343 344/* To return a NULL do this: */345#define PG_RETURN_NULL()  \346	do { fcinfo->isnull = true; return (Datum) 0; } while (0)347 348/* A few internal functions return void (which is not the same as NULL!) */349#define PG_RETURN_VOID()	 return (Datum) 0350 351/* Macros for returning results of standard types */352 353#define PG_RETURN_DATUM(x)	 return (x)354#define PG_RETURN_INT32(x)	 return Int32GetDatum(x)355#define PG_RETURN_UINT32(x)  return UInt32GetDatum(x)356#define PG_RETURN_INT16(x)	 return Int16GetDatum(x)357#define PG_RETURN_UINT16(x)  return UInt16GetDatum(x)358#define PG_RETURN_CHAR(x)	 return CharGetDatum(x)359#define PG_RETURN_BOOL(x)	 return BoolGetDatum(x)360#define PG_RETURN_OID(x)	 return ObjectIdGetDatum(x)361#define PG_RETURN_POINTER(x) return PointerGetDatum(x)362#define PG_RETURN_CSTRING(x) return CStringGetDatum(x)363#define PG_RETURN_NAME(x)	 return NameGetDatum(x)364#define PG_RETURN_TRANSACTIONID(x)	return TransactionIdGetDatum(x)365/* these macros hide the pass-by-reference-ness of the datatype: */366#define PG_RETURN_FLOAT4(x)  return Float4GetDatum(x)367#define PG_RETURN_FLOAT8(x)  return Float8GetDatum(x)368#define PG_RETURN_INT64(x)	 return Int64GetDatum(x)369#define PG_RETURN_UINT64(x)  return UInt64GetDatum(x)370/* RETURN macros for other pass-by-ref types will typically look like this: */371#define PG_RETURN_BYTEA_P(x)   PG_RETURN_POINTER(x)372#define PG_RETURN_TEXT_P(x)    PG_RETURN_POINTER(x)373#define PG_RETURN_BPCHAR_P(x)  PG_RETURN_POINTER(x)374#define PG_RETURN_VARCHAR_P(x) PG_RETURN_POINTER(x)375#define PG_RETURN_HEAPTUPLEHEADER(x)  return HeapTupleHeaderGetDatum(x)376 377 378/*-------------------------------------------------------------------------379 *		Support for detecting call convention of dynamically-loaded functions380 *381 * Dynamically loaded functions currently can only use the version-1 ("new382 * style") calling convention.  Version-0 ("old style") is not supported383 * anymore.  Version 1 is the call convention defined in this header file, and384 * must be accompanied by the macro call385 *386 *		PG_FUNCTION_INFO_V1(function_name);387 *388 * Note that internal functions do not need this decoration since they are389 * assumed to be version-1.390 *391 *-------------------------------------------------------------------------392 */393 394typedef struct395{396	int			api_version;	/* specifies call convention version number */397	/* More fields may be added later, for version numbers > 1. */398} Pg_finfo_record;399 400/* Expected signature of an info function */401typedef const Pg_finfo_record *(*PGFInfoFunction) (void);402 403/*404 *	Macro to build an info function associated with the given function name.405 *406 *	As a convenience, also provide an "extern" declaration for the given407 *	function name, so that writers of C functions need not write that too.408 *409 *	On Windows, the function and info function must be exported.  Our normal410 *	build processes take care of that via .DEF files or --export-all-symbols.411 *	Module authors using a different build process might need to manually412 *	declare the function PGDLLEXPORT.  We do that automatically here for the413 *	info function, since authors shouldn't need to be explicitly aware of it.414 */415#define PG_FUNCTION_INFO_V1(funcname) \416extern PGDLLEXPORT Datum funcname(PG_FUNCTION_ARGS); \417extern PGDLLEXPORT const Pg_finfo_record * CppConcat(pg_finfo_,funcname)(void); \418const Pg_finfo_record * \419CppConcat(pg_finfo_,funcname) (void) \420{ \421	static const Pg_finfo_record my_finfo = { 1 }; \422	return &my_finfo; \423} \424extern int no_such_variable425 426 427/*428 * Declare _PG_init/_PG_fini centrally. Historically each shared library had429 * its own declaration; but now that we want to mark these PGDLLEXPORT, using430 * central declarations avoids each extension having to add that.  Any431 * existing declarations in extensions will continue to work if fmgr.h is432 * included before them, otherwise compilation for Windows will fail.433 */434extern PGDLLEXPORT void _PG_init(void);435extern PGDLLEXPORT void _PG_fini(void);436 437 438/*-------------------------------------------------------------------------439 *		Support for verifying backend compatibility of loaded modules440 *441 * We require dynamically-loaded modules to include the macro call442 *		PG_MODULE_MAGIC;443 * so that we can check for obvious incompatibility, such as being compiled444 * for a different major PostgreSQL version.445 *446 * To compile with versions of PostgreSQL that do not support this,447 * you may put an #ifdef/#endif test around it.  Note that in a multiple-448 * source-file module, the macro call should only appear once.449 *450 * The specific items included in the magic block are intended to be ones that451 * are custom-configurable and especially likely to break dynamically loaded452 * modules if they were compiled with other values.  Also, the length field453 * can be used to detect definition changes.454 *455 * Note: we compare magic blocks with memcmp(), so there had better not be456 * any alignment pad bytes in them.457 *458 * Note: when changing the contents of magic blocks, be sure to adjust the459 * incompatible_module_error() function in dfmgr.c.460 *-------------------------------------------------------------------------461 */462 463/* Definition of the magic block structure */464typedef struct465{466	int			len;			/* sizeof(this struct) */467	int			version;		/* PostgreSQL major version */468	int			funcmaxargs;	/* FUNC_MAX_ARGS */469	int			indexmaxkeys;	/* INDEX_MAX_KEYS */470	int			namedatalen;	/* NAMEDATALEN */471	int			float8byval;	/* FLOAT8PASSBYVAL */472	char		abi_extra[32];	/* see pg_config_manual.h */473} Pg_magic_struct;474 475/* The actual data block contents */476#define PG_MODULE_MAGIC_DATA \477{ \478	sizeof(Pg_magic_struct), \479	PG_VERSION_NUM / 100, \480	FUNC_MAX_ARGS, \481	INDEX_MAX_KEYS, \482	NAMEDATALEN, \483	FLOAT8PASSBYVAL, \484	FMGR_ABI_EXTRA, \485}486 487StaticAssertDecl(sizeof(FMGR_ABI_EXTRA) <= sizeof(((Pg_magic_struct *) 0)->abi_extra),488				 "FMGR_ABI_EXTRA too long");489 490/*491 * Declare the module magic function.  It needs to be a function as the dlsym492 * in the backend is only guaranteed to work on functions, not data493 */494typedef const Pg_magic_struct *(*PGModuleMagicFunction) (void);495 496#define PG_MAGIC_FUNCTION_NAME Pg_magic_func497#define PG_MAGIC_FUNCTION_NAME_STRING "Pg_magic_func"498 499#define PG_MODULE_MAGIC \500extern PGDLLEXPORT const Pg_magic_struct *PG_MAGIC_FUNCTION_NAME(void); \501const Pg_magic_struct * \502PG_MAGIC_FUNCTION_NAME(void) \503{ \504	static const Pg_magic_struct Pg_magic_data = PG_MODULE_MAGIC_DATA; \505	return &Pg_magic_data; \506} \507extern int no_such_variable508 509 510/*-------------------------------------------------------------------------511 *		Support routines and macros for callers of fmgr-compatible functions512 *-------------------------------------------------------------------------513 */514 515/* These are for invocation of a specifically named function with a516 * directly-computed parameter list.  Note that neither arguments nor result517 * are allowed to be NULL.  Also, the function cannot be one that needs to518 * look at FmgrInfo, since there won't be any.519 */520extern Datum DirectFunctionCall1Coll(PGFunction func, Oid collation,521									 Datum arg1);522extern Datum DirectFunctionCall2Coll(PGFunction func, Oid collation,523									 Datum arg1, Datum arg2);524extern Datum DirectFunctionCall3Coll(PGFunction func, Oid collation,525									 Datum arg1, Datum arg2,526									 Datum arg3);527extern Datum DirectFunctionCall4Coll(PGFunction func, Oid collation,528									 Datum arg1, Datum arg2,529									 Datum arg3, Datum arg4);530extern Datum DirectFunctionCall5Coll(PGFunction func, Oid collation,531									 Datum arg1, Datum arg2,532									 Datum arg3, Datum arg4, Datum arg5);533extern Datum DirectFunctionCall6Coll(PGFunction func, Oid collation,534									 Datum arg1, Datum arg2,535									 Datum arg3, Datum arg4, Datum arg5,536									 Datum arg6);537extern Datum DirectFunctionCall7Coll(PGFunction func, Oid collation,538									 Datum arg1, Datum arg2,539									 Datum arg3, Datum arg4, Datum arg5,540									 Datum arg6, Datum arg7);541extern Datum DirectFunctionCall8Coll(PGFunction func, Oid collation,542									 Datum arg1, Datum arg2,543									 Datum arg3, Datum arg4, Datum arg5,544									 Datum arg6, Datum arg7, Datum arg8);545extern Datum DirectFunctionCall9Coll(PGFunction func, Oid collation,546									 Datum arg1, Datum arg2,547									 Datum arg3, Datum arg4, Datum arg5,548									 Datum arg6, Datum arg7, Datum arg8,549									 Datum arg9);550 551/*552 * These functions work like the DirectFunctionCall functions except that553 * they use the flinfo parameter to initialise the fcinfo for the call.554 * It's recommended that the callee only use the fn_extra and fn_mcxt555 * fields, as other fields will typically describe the calling function556 * not the callee.  Conversely, the calling function should not have557 * used fn_extra, unless its use is known to be compatible with the callee's.558 */559extern Datum CallerFInfoFunctionCall1(PGFunction func, FmgrInfo *flinfo,560									  Oid collation, Datum arg1);561extern Datum CallerFInfoFunctionCall2(PGFunction func, FmgrInfo *flinfo,562									  Oid collation, Datum arg1, Datum arg2);563 564/* These are for invocation of a previously-looked-up function with a565 * directly-computed parameter list.  Note that neither arguments nor result566 * are allowed to be NULL.567 */568extern Datum FunctionCall0Coll(FmgrInfo *flinfo, Oid collation);569extern Datum FunctionCall1Coll(FmgrInfo *flinfo, Oid collation,570							   Datum arg1);571extern Datum FunctionCall2Coll(FmgrInfo *flinfo, Oid collation,572							   Datum arg1, Datum arg2);573extern Datum FunctionCall3Coll(FmgrInfo *flinfo, Oid collation,574							   Datum arg1, Datum arg2,575							   Datum arg3);576extern Datum FunctionCall4Coll(FmgrInfo *flinfo, Oid collation,577							   Datum arg1, Datum arg2,578							   Datum arg3, Datum arg4);579extern Datum FunctionCall5Coll(FmgrInfo *flinfo, Oid collation,580							   Datum arg1, Datum arg2,581							   Datum arg3, Datum arg4, Datum arg5);582extern Datum FunctionCall6Coll(FmgrInfo *flinfo, Oid collation,583							   Datum arg1, Datum arg2,584							   Datum arg3, Datum arg4, Datum arg5,585							   Datum arg6);586extern Datum FunctionCall7Coll(FmgrInfo *flinfo, Oid collation,587							   Datum arg1, Datum arg2,588							   Datum arg3, Datum arg4, Datum arg5,589							   Datum arg6, Datum arg7);590extern Datum FunctionCall8Coll(FmgrInfo *flinfo, Oid collation,591							   Datum arg1, Datum arg2,592							   Datum arg3, Datum arg4, Datum arg5,593							   Datum arg6, Datum arg7, Datum arg8);594extern Datum FunctionCall9Coll(FmgrInfo *flinfo, Oid collation,595							   Datum arg1, Datum arg2,596							   Datum arg3, Datum arg4, Datum arg5,597							   Datum arg6, Datum arg7, Datum arg8,598							   Datum arg9);599 600/* These are for invocation of a function identified by OID with a601 * directly-computed parameter list.  Note that neither arguments nor result602 * are allowed to be NULL.  These are essentially fmgr_info() followed by603 * FunctionCallN().  If the same function is to be invoked repeatedly, do the604 * fmgr_info() once and then use FunctionCallN().605 */606extern Datum OidFunctionCall0Coll(Oid functionId, Oid collation);607extern Datum OidFunctionCall1Coll(Oid functionId, Oid collation,608								  Datum arg1);609extern Datum OidFunctionCall2Coll(Oid functionId, Oid collation,610								  Datum arg1, Datum arg2);611extern Datum OidFunctionCall3Coll(Oid functionId, Oid collation,612								  Datum arg1, Datum arg2,613								  Datum arg3);614extern Datum OidFunctionCall4Coll(Oid functionId, Oid collation,615								  Datum arg1, Datum arg2,616								  Datum arg3, Datum arg4);617extern Datum OidFunctionCall5Coll(Oid functionId, Oid collation,618								  Datum arg1, Datum arg2,619								  Datum arg3, Datum arg4, Datum arg5);620extern Datum OidFunctionCall6Coll(Oid functionId, Oid collation,621								  Datum arg1, Datum arg2,622								  Datum arg3, Datum arg4, Datum arg5,623								  Datum arg6);624extern Datum OidFunctionCall7Coll(Oid functionId, Oid collation,625								  Datum arg1, Datum arg2,626								  Datum arg3, Datum arg4, Datum arg5,627								  Datum arg6, Datum arg7);628extern Datum OidFunctionCall8Coll(Oid functionId, Oid collation,629								  Datum arg1, Datum arg2,630								  Datum arg3, Datum arg4, Datum arg5,631								  Datum arg6, Datum arg7, Datum arg8);632extern Datum OidFunctionCall9Coll(Oid functionId, Oid collation,633								  Datum arg1, Datum arg2,634								  Datum arg3, Datum arg4, Datum arg5,635								  Datum arg6, Datum arg7, Datum arg8,636								  Datum arg9);637 638/* These macros allow the collation argument to be omitted (with a default of639 * InvalidOid, ie, no collation).  They exist mostly for backwards640 * compatibility of source code.641 */642#define DirectFunctionCall1(func, arg1) \643	DirectFunctionCall1Coll(func, InvalidOid, arg1)644#define DirectFunctionCall2(func, arg1, arg2) \645	DirectFunctionCall2Coll(func, InvalidOid, arg1, arg2)646#define DirectFunctionCall3(func, arg1, arg2, arg3) \647	DirectFunctionCall3Coll(func, InvalidOid, arg1, arg2, arg3)648#define DirectFunctionCall4(func, arg1, arg2, arg3, arg4) \649	DirectFunctionCall4Coll(func, InvalidOid, arg1, arg2, arg3, arg4)650#define DirectFunctionCall5(func, arg1, arg2, arg3, arg4, arg5) \651	DirectFunctionCall5Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5)652#define DirectFunctionCall6(func, arg1, arg2, arg3, arg4, arg5, arg6) \653	DirectFunctionCall6Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6)654#define DirectFunctionCall7(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \655	DirectFunctionCall7Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7)656#define DirectFunctionCall8(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \657	DirectFunctionCall8Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)658#define DirectFunctionCall9(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \659	DirectFunctionCall9Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)660#define FunctionCall1(flinfo, arg1) \661	FunctionCall1Coll(flinfo, InvalidOid, arg1)662#define FunctionCall2(flinfo, arg1, arg2) \663	FunctionCall2Coll(flinfo, InvalidOid, arg1, arg2)664#define FunctionCall3(flinfo, arg1, arg2, arg3) \665	FunctionCall3Coll(flinfo, InvalidOid, arg1, arg2, arg3)666#define FunctionCall4(flinfo, arg1, arg2, arg3, arg4) \667	FunctionCall4Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4)668#define FunctionCall5(flinfo, arg1, arg2, arg3, arg4, arg5) \669	FunctionCall5Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5)670#define FunctionCall6(flinfo, arg1, arg2, arg3, arg4, arg5, arg6) \671	FunctionCall6Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6)672#define FunctionCall7(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \673	FunctionCall7Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7)674#define FunctionCall8(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \675	FunctionCall8Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)676#define FunctionCall9(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \677	FunctionCall9Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)678#define OidFunctionCall0(functionId) \679	OidFunctionCall0Coll(functionId, InvalidOid)680#define OidFunctionCall1(functionId, arg1) \681	OidFunctionCall1Coll(functionId, InvalidOid, arg1)682#define OidFunctionCall2(functionId, arg1, arg2) \683	OidFunctionCall2Coll(functionId, InvalidOid, arg1, arg2)684#define OidFunctionCall3(functionId, arg1, arg2, arg3) \685	OidFunctionCall3Coll(functionId, InvalidOid, arg1, arg2, arg3)686#define OidFunctionCall4(functionId, arg1, arg2, arg3, arg4) \687	OidFunctionCall4Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4)688#define OidFunctionCall5(functionId, arg1, arg2, arg3, arg4, arg5) \689	OidFunctionCall5Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5)690#define OidFunctionCall6(functionId, arg1, arg2, arg3, arg4, arg5, arg6) \691	OidFunctionCall6Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6)692#define OidFunctionCall7(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \693	OidFunctionCall7Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7)694#define OidFunctionCall8(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \695	OidFunctionCall8Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)696#define OidFunctionCall9(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \697	OidFunctionCall9Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)698 699 700/* Special cases for convenient invocation of datatype I/O functions. */701extern Datum InputFunctionCall(FmgrInfo *flinfo, char *str,702							   Oid typioparam, int32 typmod);703extern bool InputFunctionCallSafe(FmgrInfo *flinfo, char *str,704								  Oid typioparam, int32 typmod,705								  fmNodePtr escontext,706								  Datum *result);707extern bool DirectInputFunctionCallSafe(PGFunction func, char *str,708										Oid typioparam, int32 typmod,709										fmNodePtr escontext,710										Datum *result);711extern Datum OidInputFunctionCall(Oid functionId, char *str,712								  Oid typioparam, int32 typmod);713extern char *OutputFunctionCall(FmgrInfo *flinfo, Datum val);714extern char *OidOutputFunctionCall(Oid functionId, Datum val);715extern Datum ReceiveFunctionCall(FmgrInfo *flinfo, fmStringInfo buf,716								 Oid typioparam, int32 typmod);717extern Datum OidReceiveFunctionCall(Oid functionId, fmStringInfo buf,718									Oid typioparam, int32 typmod);719extern bytea *SendFunctionCall(FmgrInfo *flinfo, Datum val);720extern bytea *OidSendFunctionCall(Oid functionId, Datum val);721 722 723/*724 * Routines in fmgr.c725 */726extern const Pg_finfo_record *fetch_finfo_record(void *filehandle, const char *funcname);727extern Oid	fmgr_internal_function(const char *proname);728extern Oid	get_fn_expr_rettype(FmgrInfo *flinfo);729extern Oid	get_fn_expr_argtype(FmgrInfo *flinfo, int argnum);730extern Oid	get_call_expr_argtype(fmNodePtr expr, int argnum);731extern bool get_fn_expr_arg_stable(FmgrInfo *flinfo, int argnum);732extern bool get_call_expr_arg_stable(fmNodePtr expr, int argnum);733extern bool get_fn_expr_variadic(FmgrInfo *flinfo);734extern bytea *get_fn_opclass_options(FmgrInfo *flinfo);735extern bool has_fn_opclass_options(FmgrInfo *flinfo);736extern void set_fn_opclass_options(FmgrInfo *flinfo, bytea *options);737extern bool CheckFunctionValidatorAccess(Oid validatorOid, Oid functionOid);738 739/*740 * Routines in dfmgr.c741 */742extern PGDLLIMPORT char *Dynamic_library_path;743 744extern void *load_external_function(const char *filename, const char *funcname,745									bool signalNotFound, void **filehandle);746extern void *lookup_external_function(void *filehandle, const char *funcname);747extern void load_file(const char *filename, bool restricted);748extern void **find_rendezvous_variable(const char *varName);749extern Size EstimateLibraryStateSpace(void);750extern void SerializeLibraryState(Size maxsize, char *start_address);751extern void RestoreLibraryState(char *start_address);752 753/*754 * Support for aggregate functions755 *756 * These are actually in executor/nodeAgg.c, but we declare them here since757 * the whole point is for callers to not be overly friendly with nodeAgg.758 */759 760/* AggCheckCallContext can return one of the following codes, or 0: */761#define AGG_CONTEXT_AGGREGATE	1	/* regular aggregate */762#define AGG_CONTEXT_WINDOW		2	/* window function */763 764extern int	AggCheckCallContext(FunctionCallInfo fcinfo,765								MemoryContext *aggcontext);766extern fmAggrefPtr AggGetAggref(FunctionCallInfo fcinfo);767extern MemoryContext AggGetTempMemoryContext(FunctionCallInfo fcinfo);768extern bool AggStateIsShared(FunctionCallInfo fcinfo);769extern void AggRegisterCallback(FunctionCallInfo fcinfo,770								fmExprContextCallbackFunction func,771								Datum arg);772 773/*774 * We allow plugin modules to hook function entry/exit.  This is intended775 * as support for loadable security policy modules, which may want to776 * perform additional privilege checks on function entry or exit, or to do777 * other internal bookkeeping.  To make this possible, such modules must be778 * able not only to support normal function entry and exit, but also to trap779 * the case where we bail out due to an error; and they must also be able to780 * prevent inlining.781 */782typedef enum FmgrHookEventType783{784	FHET_START,785	FHET_END,786	FHET_ABORT787} FmgrHookEventType;788 789typedef bool (*needs_fmgr_hook_type) (Oid fn_oid);790 791typedef void (*fmgr_hook_type) (FmgrHookEventType event,792								FmgrInfo *flinfo, Datum *arg);793 794extern PGDLLIMPORT needs_fmgr_hook_type needs_fmgr_hook;795extern PGDLLIMPORT fmgr_hook_type fmgr_hook;796 797#define FmgrHookIsNeeded(fn_oid)							\798	(!needs_fmgr_hook ? false : (*needs_fmgr_hook)(fn_oid))799 800#endif							/* FMGR_H */801