1/*-------------------------------------------------------------------------
2 *
3 * fmgr.h
4 * Definitions for the Postgres function manager and function-call
5 * interface.
6 *
7 * This file must be included by all Postgres modules that either define
8 * or call fmgr-callable functions.
9 *
10 *
11 * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
12 * Portions Copyright (c) 1994, Regents of the University of California
13 *
14 * src/include/fmgr.h
15 *
16 *-------------------------------------------------------------------------
17 */
18#ifndef FMGR_H
19#define FMGR_H
20
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 this
35 * 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 up
44 * before a function can be called through fmgr. If the same function is
45 * to be called multiple times, the lookup need be done only once and the
46 * info struct saved for re-use.
47 *
48 * Note that fn_expr really is parse-time-determined information about the
49 * arguments, rather than about the function itself. But it's convenient to
50 * store it here rather than in FunctionCallInfoBaseData, where it might more
51 * logically belong.
52 *
53 * fn_extra is available for use by the called function; all other fields
54 * should be treated as read-only after the struct is created.
55 */
56typedef struct FmgrInfo
57{
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 or
73 * fields in whatever resultinfo points to. It should not change any other
74 * 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 using
78 * SizeForFunctionCallInfo() in dynamic allocations, or by using
79 * LOCAL_FCINFO() for on-stack allocations.
80 *
81 * This struct is named *BaseData, rather than *Data, to break pre v12 code
82 * that allocated FunctionCallInfoData itself, as it'd often silently break
83 * old code due to no space for arguments being provided.
84 */
85typedef struct FunctionCallInfoBaseData
86{
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 4
92 bool isnull; /* function must set true if result is NULL */
93 short nargs; /* # arguments actually passed */
94#define FIELDNO_FUNCTIONCALLINFODATA_ARGS 6
95 NullableDatum args[FLEXIBLE_ARRAY_MEMBER];
96} FunctionCallInfoBaseData;
97
98/*
99 * Space needed for a FunctionCallInfoBaseData struct with sufficient space
100 * 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-allocated
108 * 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.fcinfo
119
120/*
121 * This routine fills a FmgrInfo struct, given the OID
122 * 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 than
128 * CurrentMemoryContext. The specified context will be set as fn_mcxt
129 * 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 struct
140 */
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 except
148 * 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 FunctionCallInfoBaseData
162 * struct. The macro result is the returned Datum --- but note that
163 * caller must still check fcinfo->isnull! Also, if function is strict,
164 * it is caller's responsibility to verify that no null arguments are present
165 * before calling.
166 */
167#define FunctionCallInvoke(fcinfo) ((* (fcinfo)->flinfo->fn_addr) (fcinfo))
168
169
170/*-------------------------------------------------------------------------
171 * Support macros to ease writing fmgr-compatible functions
172 *
173 * A C-coded fmgr-compatible function should be declared as
174 *
175 * Datum
176 * function_name(PG_FUNCTION_ARGS)
177 * {
178 * ...
179 * }
180 *
181 * It should access its arguments using appropriate PG_GETARG_xxx macros
182 * and should return its result using PG_RETURN_xxx.
183 *
184 *-------------------------------------------------------------------------
185 */
186
187/* Standard parameter list for fmgr-compatible functions */
188#define PG_FUNCTION_ARGS FunctionCallInfo fcinfo
189
190/*
191 * Get collation function should use.
192 */
193#define PG_GET_COLLATION() (fcinfo->fncollation)
194
195/*
196 * Get number of arguments passed to function.
197 */
198#define PG_NARGS() (fcinfo->nargs)
199
200/*
201 * If function is not marked "proisstrict" in pg_proc, it must check for
202 * null arguments using this macro. Do not try to GETARG a null argument!
203 */
204#define PG_ARGISNULL(n) (fcinfo->args[n].isnull)
205
206/*
207 * Support for fetching detoasted copies of toastable datatypes (all of
208 * which are varlena types). pg_detoast_datum() gives you either the input
209 * datum (if not toasted) or a detoasted copy allocated with palloc().
210 * pg_detoast_datum_copy() always gives you a palloc'd copy --- use it
211 * if you need a modifiable copy of the input. Caller is expected to have
212 * checked for null inputs first, if necessary.
213 *
214 * pg_detoast_datum_packed() will return packed (1-byte header) datums
215 * unmodified. It will still expand an externally toasted or compressed datum.
216 * The resulting datum can be accessed using VARSIZE_ANY() and VARDATA_ANY()
217 * (beware of multiple evaluations in those macros!)
218 *
219 * In consumers oblivious to data alignment, call PG_DETOAST_DATUM_PACKED(),
220 * VARDATA_ANY(), VARSIZE_ANY() and VARSIZE_ANY_EXHDR(). Elsewhere, call
221 * PG_DETOAST_DATUM(), VARDATA() and VARSIZE(). Directly fetching an int16,
222 * int32 or wider field in the struct representing the datum layout requires
223 * aligned data. memcpy() is alignment-oblivious, as are most operations on
224 * datatypes, such as text, whose layout struct contains only char fields.
225 *
226 * Note: it'd be nice if these could be macros, but I see no way to do that
227 * without evaluating the arguments multiple times, which is NOT acceptable.
228 */
229extern struct varlena *pg_detoast_datum(struct varlena *datum);
230extern struct varlena *pg_detoast_datum_copy(struct varlena *datum);
231extern struct varlena *pg_detoast_datum_slice(struct varlena *datum,
232 int32 first, int32 count);
233extern struct varlena *pg_detoast_datum_packed(struct varlena *datum);
234
235#define PG_DETOAST_DATUM(datum) \
236 pg_detoast_datum((struct varlena *) DatumGetPointer(datum))
237#define PG_DETOAST_DATUM_COPY(datum) \
238 pg_detoast_datum_copy((struct varlena *) DatumGetPointer(datum))
239#define PG_DETOAST_DATUM_SLICE(datum,f,c) \
240 pg_detoast_datum_slice((struct varlena *) DatumGetPointer(datum), \
241 (int32) (f), (int32) (c))
242/* WARNING -- unaligned pointer */
243#define PG_DETOAST_DATUM_PACKED(datum) \
244 pg_detoast_datum_packed((struct varlena *) DatumGetPointer(datum))
245
246/*
247 * Support for cleaning up detoasted copies of inputs. This must only
248 * be used for pass-by-ref datatypes, and normally would only be used
249 * for toastable types. If the given pointer is different from the
250 * original argument, assume it's a palloc'd detoasted copy, and pfree it.
251 * NOTE: most functions on toastable types do not have to worry about this,
252 * but we currently require that support functions for indexes not leak
253 * memory.
254 */
255#define PG_FREE_IF_COPY(ptr,n) \
256 do { \
257 if ((Pointer) (ptr) != PG_GETARG_POINTER(n)) \
258 pfree(ptr); \
259 } while (0)
260
261/* Macros for fetching arguments of standard types */
262
263#define PG_GETARG_DATUM(n) (fcinfo->args[n].value)
264#define PG_GETARG_INT32(n) DatumGetInt32(PG_GETARG_DATUM(n))
265#define PG_GETARG_UINT32(n) DatumGetUInt32(PG_GETARG_DATUM(n))
266#define PG_GETARG_INT16(n) DatumGetInt16(PG_GETARG_DATUM(n))
267#define PG_GETARG_UINT16(n) DatumGetUInt16(PG_GETARG_DATUM(n))
268#define PG_GETARG_CHAR(n) DatumGetChar(PG_GETARG_DATUM(n))
269#define PG_GETARG_BOOL(n) DatumGetBool(PG_GETARG_DATUM(n))
270#define PG_GETARG_OID(n) DatumGetObjectId(PG_GETARG_DATUM(n))
271#define PG_GETARG_POINTER(n) DatumGetPointer(PG_GETARG_DATUM(n))
272#define PG_GETARG_CSTRING(n) DatumGetCString(PG_GETARG_DATUM(n))
273#define PG_GETARG_NAME(n) DatumGetName(PG_GETARG_DATUM(n))
274/* these macros hide the pass-by-reference-ness of the datatype: */
275#define PG_GETARG_FLOAT4(n) DatumGetFloat4(PG_GETARG_DATUM(n))
276#define PG_GETARG_FLOAT8(n) DatumGetFloat8(PG_GETARG_DATUM(n))
277#define PG_GETARG_INT64(n) DatumGetInt64(PG_GETARG_DATUM(n))
278/* use this if you want the raw, possibly-toasted input datum: */
279#define PG_GETARG_RAW_VARLENA_P(n) ((struct varlena *) PG_GETARG_POINTER(n))
280/* use this if you want the input datum de-toasted: */
281#define PG_GETARG_VARLENA_P(n) PG_DETOAST_DATUM(PG_GETARG_DATUM(n))
282/* and this if you can handle 1-byte-header datums: */
283#define PG_GETARG_VARLENA_PP(n) PG_DETOAST_DATUM_PACKED(PG_GETARG_DATUM(n))
284/* DatumGetFoo macros for varlena types will typically look like this: */
285#define DatumGetByteaPP(X) ((bytea *) PG_DETOAST_DATUM_PACKED(X))
286#define DatumGetTextPP(X) ((text *) PG_DETOAST_DATUM_PACKED(X))
287#define DatumGetBpCharPP(X) ((BpChar *) PG_DETOAST_DATUM_PACKED(X))
288#define DatumGetVarCharPP(X) ((VarChar *) PG_DETOAST_DATUM_PACKED(X))
289#define DatumGetHeapTupleHeader(X) ((HeapTupleHeader) PG_DETOAST_DATUM(X))
290/* And we also offer variants that return an OK-to-write copy */
291#define DatumGetByteaPCopy(X) ((bytea *) PG_DETOAST_DATUM_COPY(X))
292#define DatumGetTextPCopy(X) ((text *) PG_DETOAST_DATUM_COPY(X))
293#define DatumGetBpCharPCopy(X) ((BpChar *) PG_DETOAST_DATUM_COPY(X))
294#define DatumGetVarCharPCopy(X) ((VarChar *) PG_DETOAST_DATUM_COPY(X))
295#define DatumGetHeapTupleHeaderCopy(X) ((HeapTupleHeader) PG_DETOAST_DATUM_COPY(X))
296/* Variants which return n bytes starting at pos. m */
297#define DatumGetByteaPSlice(X,m,n) ((bytea *) PG_DETOAST_DATUM_SLICE(X,m,n))
298#define DatumGetTextPSlice(X,m,n) ((text *) PG_DETOAST_DATUM_SLICE(X,m,n))
299#define DatumGetBpCharPSlice(X,m,n) ((BpChar *) PG_DETOAST_DATUM_SLICE(X,m,n))
300#define DatumGetVarCharPSlice(X,m,n) ((VarChar *) PG_DETOAST_DATUM_SLICE(X,m,n))
301/* GETARG macros for varlena types will typically look like this: */
302#define PG_GETARG_BYTEA_PP(n) DatumGetByteaPP(PG_GETARG_DATUM(n))
303#define PG_GETARG_TEXT_PP(n) DatumGetTextPP(PG_GETARG_DATUM(n))
304#define PG_GETARG_BPCHAR_PP(n) DatumGetBpCharPP(PG_GETARG_DATUM(n))
305#define PG_GETARG_VARCHAR_PP(n) DatumGetVarCharPP(PG_GETARG_DATUM(n))
306#define PG_GETARG_HEAPTUPLEHEADER(n) DatumGetHeapTupleHeader(PG_GETARG_DATUM(n))
307/* And we also offer variants that return an OK-to-write copy */
308#define PG_GETARG_BYTEA_P_COPY(n) DatumGetByteaPCopy(PG_GETARG_DATUM(n))
309#define PG_GETARG_TEXT_P_COPY(n) DatumGetTextPCopy(PG_GETARG_DATUM(n))
310#define PG_GETARG_BPCHAR_P_COPY(n) DatumGetBpCharPCopy(PG_GETARG_DATUM(n))
311#define PG_GETARG_VARCHAR_P_COPY(n) DatumGetVarCharPCopy(PG_GETARG_DATUM(n))
312#define PG_GETARG_HEAPTUPLEHEADER_COPY(n) DatumGetHeapTupleHeaderCopy(PG_GETARG_DATUM(n))
313/* And a b-byte slice from position a -also OK to write */
314#define PG_GETARG_BYTEA_P_SLICE(n,a,b) DatumGetByteaPSlice(PG_GETARG_DATUM(n),a,b)
315#define PG_GETARG_TEXT_P_SLICE(n,a,b) DatumGetTextPSlice(PG_GETARG_DATUM(n),a,b)
316#define PG_GETARG_BPCHAR_P_SLICE(n,a,b) DatumGetBpCharPSlice(PG_GETARG_DATUM(n),a,b)
317#define PG_GETARG_VARCHAR_P_SLICE(n,a,b) DatumGetVarCharPSlice(PG_GETARG_DATUM(n),a,b)
318/*
319 * Obsolescent variants that guarantee INT alignment for the return value.
320 * Few operations on these particular types need alignment, mainly operations
321 * that cast the VARDATA pointer to a type like int16[]. Most code should use
322 * the ...PP(X) counterpart. Nonetheless, these appear frequently in code
323 * predating the PostgreSQL 8.3 introduction of the ...PP(X) variants.
324 */
325#define DatumGetByteaP(X) ((bytea *) PG_DETOAST_DATUM(X))
326#define DatumGetTextP(X) ((text *) PG_DETOAST_DATUM(X))
327#define DatumGetBpCharP(X) ((BpChar *) PG_DETOAST_DATUM(X))
328#define DatumGetVarCharP(X) ((VarChar *) PG_DETOAST_DATUM(X))
329#define PG_GETARG_BYTEA_P(n) DatumGetByteaP(PG_GETARG_DATUM(n))
330#define PG_GETARG_TEXT_P(n) DatumGetTextP(PG_GETARG_DATUM(n))
331#define PG_GETARG_BPCHAR_P(n) DatumGetBpCharP(PG_GETARG_DATUM(n))
332#define PG_GETARG_VARCHAR_P(n) DatumGetVarCharP(PG_GETARG_DATUM(n))
333
334/* To return a NULL do this: */
335#define PG_RETURN_NULL() \
336 do { fcinfo->isnull = true; return (Datum) 0; } while (0)
337
338/* A few internal functions return void (which is not the same as NULL!) */
339#define PG_RETURN_VOID() return (Datum) 0
340
341/* Macros for returning results of standard types */
342
343#define PG_RETURN_DATUM(x) return (x)
344#define PG_RETURN_INT32(x) return Int32GetDatum(x)
345#define PG_RETURN_UINT32(x) return UInt32GetDatum(x)
346#define PG_RETURN_INT16(x) return Int16GetDatum(x)
347#define PG_RETURN_UINT16(x) return UInt16GetDatum(x)
348#define PG_RETURN_CHAR(x) return CharGetDatum(x)
349#define PG_RETURN_BOOL(x) return BoolGetDatum(x)
350#define PG_RETURN_OID(x) return ObjectIdGetDatum(x)
351#define PG_RETURN_POINTER(x) return PointerGetDatum(x)
352#define PG_RETURN_CSTRING(x) return CStringGetDatum(x)
353#define PG_RETURN_NAME(x) return NameGetDatum(x)
354/* these macros hide the pass-by-reference-ness of the datatype: */
355#define PG_RETURN_FLOAT4(x) return Float4GetDatum(x)
356#define PG_RETURN_FLOAT8(x) return Float8GetDatum(x)
357#define PG_RETURN_INT64(x) return Int64GetDatum(x)
358#define PG_RETURN_UINT64(x) return UInt64GetDatum(x)
359/* RETURN macros for other pass-by-ref types will typically look like this: */
360#define PG_RETURN_BYTEA_P(x) PG_RETURN_POINTER(x)
361#define PG_RETURN_TEXT_P(x) PG_RETURN_POINTER(x)
362#define PG_RETURN_BPCHAR_P(x) PG_RETURN_POINTER(x)
363#define PG_RETURN_VARCHAR_P(x) PG_RETURN_POINTER(x)
364#define PG_RETURN_HEAPTUPLEHEADER(x) return HeapTupleHeaderGetDatum(x)
365
366
367/*-------------------------------------------------------------------------
368 * Support for detecting call convention of dynamically-loaded functions
369 *
370 * Dynamically loaded functions currently can only use the version-1 ("new
371 * style") calling convention. Version-0 ("old style") is not supported
372 * anymore. Version 1 is the call convention defined in this header file, and
373 * must be accompanied by the macro call
374 *
375 * PG_FUNCTION_INFO_V1(function_name);
376 *
377 * Note that internal functions do not need this decoration since they are
378 * assumed to be version-1.
379 *
380 *-------------------------------------------------------------------------
381 */
382
383typedef struct
384{
385 int api_version; /* specifies call convention version number */
386 /* More fields may be added later, for version numbers > 1. */
387} Pg_finfo_record;
388
389/* Expected signature of an info function */
390typedef const Pg_finfo_record *(*PGFInfoFunction) (void);
391
392/*
393 * Macro to build an info function associated with the given function name.
394 *
395 * As a convenience, also provide an "extern" declaration for the given
396 * function name, so that writers of C functions need not write that too.
397 *
398 * On Windows, the function and info function must be exported. Our normal
399 * build processes take care of that via .DEF files or --export-all-symbols.
400 * Module authors using a different build process might need to manually
401 * declare the function PGDLLEXPORT. We do that automatically here for the
402 * info function, since authors shouldn't need to be explicitly aware of it.
403 */
404#define PG_FUNCTION_INFO_V1(funcname) \
405extern Datum funcname(PG_FUNCTION_ARGS); \
406extern PGDLLEXPORT const Pg_finfo_record * CppConcat(pg_finfo_,funcname)(void); \
407const Pg_finfo_record * \
408CppConcat(pg_finfo_,funcname) (void) \
409{ \
410 static const Pg_finfo_record my_finfo = { 1 }; \
411 return &my_finfo; \
412} \
413extern int no_such_variable
414
415
416/*-------------------------------------------------------------------------
417 * Support for verifying backend compatibility of loaded modules
418 *
419 * We require dynamically-loaded modules to include the macro call
420 * PG_MODULE_MAGIC;
421 * so that we can check for obvious incompatibility, such as being compiled
422 * for a different major PostgreSQL version.
423 *
424 * To compile with versions of PostgreSQL that do not support this,
425 * you may put an #ifdef/#endif test around it. Note that in a multiple-
426 * source-file module, the macro call should only appear once.
427 *
428 * The specific items included in the magic block are intended to be ones that
429 * are custom-configurable and especially likely to break dynamically loaded
430 * modules if they were compiled with other values. Also, the length field
431 * can be used to detect definition changes.
432 *
433 * Note: we compare magic blocks with memcmp(), so there had better not be
434 * any alignment pad bytes in them.
435 *
436 * Note: when changing the contents of magic blocks, be sure to adjust the
437 * incompatible_module_error() function in dfmgr.c.
438 *-------------------------------------------------------------------------
439 */
440
441/* Definition of the magic block structure */
442typedef struct
443{
444 int len; /* sizeof(this struct) */
445 int version; /* PostgreSQL major version */
446 int funcmaxargs; /* FUNC_MAX_ARGS */
447 int indexmaxkeys; /* INDEX_MAX_KEYS */
448 int namedatalen; /* NAMEDATALEN */
449 int float4byval; /* FLOAT4PASSBYVAL */
450 int float8byval; /* FLOAT8PASSBYVAL */
451} Pg_magic_struct;
452
453/* The actual data block contents */
454#define PG_MODULE_MAGIC_DATA \
455{ \
456 sizeof(Pg_magic_struct), \
457 PG_VERSION_NUM / 100, \
458 FUNC_MAX_ARGS, \
459 INDEX_MAX_KEYS, \
460 NAMEDATALEN, \
461 FLOAT4PASSBYVAL, \
462 FLOAT8PASSBYVAL \
463}
464
465/*
466 * Declare the module magic function. It needs to be a function as the dlsym
467 * in the backend is only guaranteed to work on functions, not data
468 */
469typedef const Pg_magic_struct *(*PGModuleMagicFunction) (void);
470
471#define PG_MAGIC_FUNCTION_NAME Pg_magic_func
472#define PG_MAGIC_FUNCTION_NAME_STRING "Pg_magic_func"
473
474#define PG_MODULE_MAGIC \
475extern PGDLLEXPORT const Pg_magic_struct *PG_MAGIC_FUNCTION_NAME(void); \
476const Pg_magic_struct * \
477PG_MAGIC_FUNCTION_NAME(void) \
478{ \
479 static const Pg_magic_struct Pg_magic_data = PG_MODULE_MAGIC_DATA; \
480 return &Pg_magic_data; \
481} \
482extern int no_such_variable
483
484
485/*-------------------------------------------------------------------------
486 * Support routines and macros for callers of fmgr-compatible functions
487 *-------------------------------------------------------------------------
488 */
489
490/* These are for invocation of a specifically named function with a
491 * directly-computed parameter list. Note that neither arguments nor result
492 * are allowed to be NULL.
493 */
494extern Datum DirectFunctionCall1Coll(PGFunction func, Oid collation,
495 Datum arg1);
496extern Datum DirectFunctionCall2Coll(PGFunction func, Oid collation,
497 Datum arg1, Datum arg2);
498extern Datum DirectFunctionCall3Coll(PGFunction func, Oid collation,
499 Datum arg1, Datum arg2,
500 Datum arg3);
501extern Datum DirectFunctionCall4Coll(PGFunction func, Oid collation,
502 Datum arg1, Datum arg2,
503 Datum arg3, Datum arg4);
504extern Datum DirectFunctionCall5Coll(PGFunction func, Oid collation,
505 Datum arg1, Datum arg2,
506 Datum arg3, Datum arg4, Datum arg5);
507extern Datum DirectFunctionCall6Coll(PGFunction func, Oid collation,
508 Datum arg1, Datum arg2,
509 Datum arg3, Datum arg4, Datum arg5,
510 Datum arg6);
511extern Datum DirectFunctionCall7Coll(PGFunction func, Oid collation,
512 Datum arg1, Datum arg2,
513 Datum arg3, Datum arg4, Datum arg5,
514 Datum arg6, Datum arg7);
515extern Datum DirectFunctionCall8Coll(PGFunction func, Oid collation,
516 Datum arg1, Datum arg2,
517 Datum arg3, Datum arg4, Datum arg5,
518 Datum arg6, Datum arg7, Datum arg8);
519extern Datum DirectFunctionCall9Coll(PGFunction func, Oid collation,
520 Datum arg1, Datum arg2,
521 Datum arg3, Datum arg4, Datum arg5,
522 Datum arg6, Datum arg7, Datum arg8,
523 Datum arg9);
524
525/*
526 * These functions work like the DirectFunctionCall functions except that
527 * they use the flinfo parameter to initialise the fcinfo for the call.
528 * It's recommended that the callee only use the fn_extra and fn_mcxt
529 * fields, as other fields will typically describe the calling function
530 * not the callee. Conversely, the calling function should not have
531 * used fn_extra, unless its use is known to be compatible with the callee's.
532 */
533extern Datum CallerFInfoFunctionCall1(PGFunction func, FmgrInfo *flinfo,
534 Oid collation, Datum arg1);
535extern Datum CallerFInfoFunctionCall2(PGFunction func, FmgrInfo *flinfo,
536 Oid collation, Datum arg1, Datum arg2);
537
538/* These are for invocation of a previously-looked-up function with a
539 * directly-computed parameter list. Note that neither arguments nor result
540 * are allowed to be NULL.
541 */
542extern Datum FunctionCall0Coll(FmgrInfo *flinfo, Oid collation);
543extern Datum FunctionCall1Coll(FmgrInfo *flinfo, Oid collation,
544 Datum arg1);
545extern Datum FunctionCall2Coll(FmgrInfo *flinfo, Oid collation,
546 Datum arg1, Datum arg2);
547extern Datum FunctionCall3Coll(FmgrInfo *flinfo, Oid collation,
548 Datum arg1, Datum arg2,
549 Datum arg3);
550extern Datum FunctionCall4Coll(FmgrInfo *flinfo, Oid collation,
551 Datum arg1, Datum arg2,
552 Datum arg3, Datum arg4);
553extern Datum FunctionCall5Coll(FmgrInfo *flinfo, Oid collation,
554 Datum arg1, Datum arg2,
555 Datum arg3, Datum arg4, Datum arg5);
556extern Datum FunctionCall6Coll(FmgrInfo *flinfo, Oid collation,
557 Datum arg1, Datum arg2,
558 Datum arg3, Datum arg4, Datum arg5,
559 Datum arg6);
560extern Datum FunctionCall7Coll(FmgrInfo *flinfo, Oid collation,
561 Datum arg1, Datum arg2,
562 Datum arg3, Datum arg4, Datum arg5,
563 Datum arg6, Datum arg7);
564extern Datum FunctionCall8Coll(FmgrInfo *flinfo, Oid collation,
565 Datum arg1, Datum arg2,
566 Datum arg3, Datum arg4, Datum arg5,
567 Datum arg6, Datum arg7, Datum arg8);
568extern Datum FunctionCall9Coll(FmgrInfo *flinfo, Oid collation,
569 Datum arg1, Datum arg2,
570 Datum arg3, Datum arg4, Datum arg5,
571 Datum arg6, Datum arg7, Datum arg8,
572 Datum arg9);
573
574/* These are for invocation of a function identified by OID with a
575 * directly-computed parameter list. Note that neither arguments nor result
576 * are allowed to be NULL. These are essentially fmgr_info() followed by
577 * FunctionCallN(). If the same function is to be invoked repeatedly, do the
578 * fmgr_info() once and then use FunctionCallN().
579 */
580extern Datum OidFunctionCall0Coll(Oid functionId, Oid collation);
581extern Datum OidFunctionCall1Coll(Oid functionId, Oid collation,
582 Datum arg1);
583extern Datum OidFunctionCall2Coll(Oid functionId, Oid collation,
584 Datum arg1, Datum arg2);
585extern Datum OidFunctionCall3Coll(Oid functionId, Oid collation,
586 Datum arg1, Datum arg2,
587 Datum arg3);
588extern Datum OidFunctionCall4Coll(Oid functionId, Oid collation,
589 Datum arg1, Datum arg2,
590 Datum arg3, Datum arg4);
591extern Datum OidFunctionCall5Coll(Oid functionId, Oid collation,
592 Datum arg1, Datum arg2,
593 Datum arg3, Datum arg4, Datum arg5);
594extern Datum OidFunctionCall6Coll(Oid functionId, Oid collation,
595 Datum arg1, Datum arg2,
596 Datum arg3, Datum arg4, Datum arg5,
597 Datum arg6);
598extern Datum OidFunctionCall7Coll(Oid functionId, Oid collation,
599 Datum arg1, Datum arg2,
600 Datum arg3, Datum arg4, Datum arg5,
601 Datum arg6, Datum arg7);
602extern Datum OidFunctionCall8Coll(Oid functionId, Oid collation,
603 Datum arg1, Datum arg2,
604 Datum arg3, Datum arg4, Datum arg5,
605 Datum arg6, Datum arg7, Datum arg8);
606extern Datum OidFunctionCall9Coll(Oid functionId, Oid collation,
607 Datum arg1, Datum arg2,
608 Datum arg3, Datum arg4, Datum arg5,
609 Datum arg6, Datum arg7, Datum arg8,
610 Datum arg9);
611
612/* These macros allow the collation argument to be omitted (with a default of
613 * InvalidOid, ie, no collation). They exist mostly for backwards
614 * compatibility of source code.
615 */
616#define DirectFunctionCall1(func, arg1) \
617 DirectFunctionCall1Coll(func, InvalidOid, arg1)
618#define DirectFunctionCall2(func, arg1, arg2) \
619 DirectFunctionCall2Coll(func, InvalidOid, arg1, arg2)
620#define DirectFunctionCall3(func, arg1, arg2, arg3) \
621 DirectFunctionCall3Coll(func, InvalidOid, arg1, arg2, arg3)
622#define DirectFunctionCall4(func, arg1, arg2, arg3, arg4) \
623 DirectFunctionCall4Coll(func, InvalidOid, arg1, arg2, arg3, arg4)
624#define DirectFunctionCall5(func, arg1, arg2, arg3, arg4, arg5) \
625 DirectFunctionCall5Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5)
626#define DirectFunctionCall6(func, arg1, arg2, arg3, arg4, arg5, arg6) \
627 DirectFunctionCall6Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6)
628#define DirectFunctionCall7(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \
629 DirectFunctionCall7Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7)
630#define DirectFunctionCall8(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
631 DirectFunctionCall8Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)
632#define DirectFunctionCall9(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \
633 DirectFunctionCall9Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)
634#define FunctionCall1(flinfo, arg1) \
635 FunctionCall1Coll(flinfo, InvalidOid, arg1)
636#define FunctionCall2(flinfo, arg1, arg2) \
637 FunctionCall2Coll(flinfo, InvalidOid, arg1, arg2)
638#define FunctionCall3(flinfo, arg1, arg2, arg3) \
639 FunctionCall3Coll(flinfo, InvalidOid, arg1, arg2, arg3)
640#define FunctionCall4(flinfo, arg1, arg2, arg3, arg4) \
641 FunctionCall4Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4)
642#define FunctionCall5(flinfo, arg1, arg2, arg3, arg4, arg5) \
643 FunctionCall5Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5)
644#define FunctionCall6(flinfo, arg1, arg2, arg3, arg4, arg5, arg6) \
645 FunctionCall6Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6)
646#define FunctionCall7(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \
647 FunctionCall7Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7)
648#define FunctionCall8(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
649 FunctionCall8Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)
650#define FunctionCall9(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \
651 FunctionCall9Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)
652#define OidFunctionCall0(functionId) \
653 OidFunctionCall0Coll(functionId, InvalidOid)
654#define OidFunctionCall1(functionId, arg1) \
655 OidFunctionCall1Coll(functionId, InvalidOid, arg1)
656#define OidFunctionCall2(functionId, arg1, arg2) \
657 OidFunctionCall2Coll(functionId, InvalidOid, arg1, arg2)
658#define OidFunctionCall3(functionId, arg1, arg2, arg3) \
659 OidFunctionCall3Coll(functionId, InvalidOid, arg1, arg2, arg3)
660#define OidFunctionCall4(functionId, arg1, arg2, arg3, arg4) \
661 OidFunctionCall4Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4)
662#define OidFunctionCall5(functionId, arg1, arg2, arg3, arg4, arg5) \
663 OidFunctionCall5Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5)
664#define OidFunctionCall6(functionId, arg1, arg2, arg3, arg4, arg5, arg6) \
665 OidFunctionCall6Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6)
666#define OidFunctionCall7(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \
667 OidFunctionCall7Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7)
668#define OidFunctionCall8(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
669 OidFunctionCall8Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)
670#define OidFunctionCall9(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \
671 OidFunctionCall9Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)
672
673
674/* Special cases for convenient invocation of datatype I/O functions. */
675extern Datum InputFunctionCall(FmgrInfo *flinfo, char *str,
676 Oid typioparam, int32 typmod);
677extern Datum OidInputFunctionCall(Oid functionId, char *str,
678 Oid typioparam, int32 typmod);
679extern char *OutputFunctionCall(FmgrInfo *flinfo, Datum val);
680extern char *OidOutputFunctionCall(Oid functionId, Datum val);
681extern Datum ReceiveFunctionCall(FmgrInfo *flinfo, fmStringInfo buf,
682 Oid typioparam, int32 typmod);
683extern Datum OidReceiveFunctionCall(Oid functionId, fmStringInfo buf,
684 Oid typioparam, int32 typmod);
685extern bytea *SendFunctionCall(FmgrInfo *flinfo, Datum val);
686extern bytea *OidSendFunctionCall(Oid functionId, Datum val);
687
688
689/*
690 * Routines in fmgr.c
691 */
692extern const Pg_finfo_record *fetch_finfo_record(void *filehandle, const char *funcname);
693extern void clear_external_function_hash(void *filehandle);
694extern Oid fmgr_internal_function(const char *proname);
695extern Oid get_fn_expr_rettype(FmgrInfo *flinfo);
696extern Oid get_fn_expr_argtype(FmgrInfo *flinfo, int argnum);
697extern Oid get_call_expr_argtype(fmNodePtr expr, int argnum);
698extern bool get_fn_expr_arg_stable(FmgrInfo *flinfo, int argnum);
699extern bool get_call_expr_arg_stable(fmNodePtr expr, int argnum);
700extern bool get_fn_expr_variadic(FmgrInfo *flinfo);
701extern bool CheckFunctionValidatorAccess(Oid validatorOid, Oid functionOid);
702
703/*
704 * Routines in dfmgr.c
705 */
706extern char *Dynamic_library_path;
707
708extern PGFunction load_external_function(const char *filename, const char *funcname,
709 bool signalNotFound, void **filehandle);
710extern PGFunction lookup_external_function(void *filehandle, const char *funcname);
711extern void load_file(const char *filename, bool restricted);
712extern void **find_rendezvous_variable(const char *varName);
713extern Size EstimateLibraryStateSpace(void);
714extern void SerializeLibraryState(Size maxsize, char *start_address);
715extern void RestoreLibraryState(char *start_address);
716
717/*
718 * Support for aggregate functions
719 *
720 * These are actually in executor/nodeAgg.c, but we declare them here since
721 * the whole point is for callers to not be overly friendly with nodeAgg.
722 */
723
724/* AggCheckCallContext can return one of the following codes, or 0: */
725#define AGG_CONTEXT_AGGREGATE 1 /* regular aggregate */
726#define AGG_CONTEXT_WINDOW 2 /* window function */
727
728extern int AggCheckCallContext(FunctionCallInfo fcinfo,
729 MemoryContext *aggcontext);
730extern fmAggrefPtr AggGetAggref(FunctionCallInfo fcinfo);
731extern MemoryContext AggGetTempMemoryContext(FunctionCallInfo fcinfo);
732extern bool AggStateIsShared(FunctionCallInfo fcinfo);
733extern void AggRegisterCallback(FunctionCallInfo fcinfo,
734 fmExprContextCallbackFunction func,
735 Datum arg);
736
737/*
738 * We allow plugin modules to hook function entry/exit. This is intended
739 * as support for loadable security policy modules, which may want to
740 * perform additional privilege checks on function entry or exit, or to do
741 * other internal bookkeeping. To make this possible, such modules must be
742 * able not only to support normal function entry and exit, but also to trap
743 * the case where we bail out due to an error; and they must also be able to
744 * prevent inlining.
745 */
746typedef enum FmgrHookEventType
747{
748 FHET_START,
749 FHET_END,
750 FHET_ABORT
751} FmgrHookEventType;
752
753typedef bool (*needs_fmgr_hook_type) (Oid fn_oid);
754
755typedef void (*fmgr_hook_type) (FmgrHookEventType event,
756 FmgrInfo *flinfo, Datum *arg);
757
758extern PGDLLIMPORT needs_fmgr_hook_type needs_fmgr_hook;
759extern PGDLLIMPORT fmgr_hook_type fmgr_hook;
760
761#define FmgrHookIsNeeded(fn_oid) \
762 (!needs_fmgr_hook ? false : (*needs_fmgr_hook)(fn_oid))
763
764#endif /* FMGR_H */
765