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Diffstat (limited to '')
| -rw-r--r-- | src/include/fmgr.h | 800 |
1 files changed, 800 insertions, 0 deletions
diff --git a/src/include/fmgr.h b/src/include/fmgr.h new file mode 100644 index 0000000..b120f5e --- /dev/null +++ b/src/include/fmgr.h @@ -0,0 +1,800 @@ +/*------------------------------------------------------------------------- + * + * fmgr.h + * Definitions for the Postgres function manager and function-call + * interface. + * + * This file must be included by all Postgres modules that either define + * or call fmgr-callable functions. + * + * + * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/fmgr.h + * + *------------------------------------------------------------------------- + */ +#ifndef FMGR_H +#define FMGR_H + +/* We don't want to include primnodes.h here, so make some stub references */ +typedef struct Node *fmNodePtr; +typedef struct Aggref *fmAggrefPtr; + +/* Likewise, avoid including execnodes.h here */ +typedef void (*fmExprContextCallbackFunction) (Datum arg); + +/* Likewise, avoid including stringinfo.h here */ +typedef struct StringInfoData *fmStringInfo; + + +/* + * All functions that can be called directly by fmgr must have this signature. + * (Other functions can be called by using a handler that does have this + * signature.) + */ + +typedef struct FunctionCallInfoBaseData *FunctionCallInfo; + +typedef Datum (*PGFunction) (FunctionCallInfo fcinfo); + +/* + * This struct holds the system-catalog information that must be looked up + * before a function can be called through fmgr. If the same function is + * to be called multiple times, the lookup need be done only once and the + * info struct saved for re-use. + * + * Note that fn_expr really is parse-time-determined information about the + * arguments, rather than about the function itself. But it's convenient to + * store it here rather than in FunctionCallInfoBaseData, where it might more + * logically belong. + * + * fn_extra is available for use by the called function; all other fields + * should be treated as read-only after the struct is created. + */ +typedef struct FmgrInfo +{ + PGFunction fn_addr; /* pointer to function or handler to be called */ + Oid fn_oid; /* OID of function (NOT of handler, if any) */ + short fn_nargs; /* number of input args (0..FUNC_MAX_ARGS) */ + bool fn_strict; /* function is "strict" (NULL in => NULL out) */ + bool fn_retset; /* function returns a set */ + unsigned char fn_stats; /* collect stats if track_functions > this */ + void *fn_extra; /* extra space for use by handler */ + MemoryContext fn_mcxt; /* memory context to store fn_extra in */ + fmNodePtr fn_expr; /* expression parse tree for call, or NULL */ +} FmgrInfo; + +/* + * This struct is the data actually passed to an fmgr-called function. + * + * The called function is expected to set isnull, and possibly resultinfo or + * fields in whatever resultinfo points to. It should not change any other + * fields. (In particular, scribbling on the argument arrays is a bad idea, + * since some callers assume they can re-call with the same arguments.) + * + * Note that enough space for arguments needs to be provided, either by using + * SizeForFunctionCallInfo() in dynamic allocations, or by using + * LOCAL_FCINFO() for on-stack allocations. + * + * This struct is named *BaseData, rather than *Data, to break pre v12 code + * that allocated FunctionCallInfoData itself, as it'd often silently break + * old code due to no space for arguments being provided. + */ +typedef struct FunctionCallInfoBaseData +{ + FmgrInfo *flinfo; /* ptr to lookup info used for this call */ + fmNodePtr context; /* pass info about context of call */ + fmNodePtr resultinfo; /* pass or return extra info about result */ + Oid fncollation; /* collation for function to use */ +#define FIELDNO_FUNCTIONCALLINFODATA_ISNULL 4 + bool isnull; /* function must set true if result is NULL */ + short nargs; /* # arguments actually passed */ +#define FIELDNO_FUNCTIONCALLINFODATA_ARGS 6 + NullableDatum args[FLEXIBLE_ARRAY_MEMBER]; +} FunctionCallInfoBaseData; + +/* + * Space needed for a FunctionCallInfoBaseData struct with sufficient space + * for `nargs` arguments. + */ +#define SizeForFunctionCallInfo(nargs) \ + (offsetof(FunctionCallInfoBaseData, args) + \ + sizeof(NullableDatum) * (nargs)) + +/* + * This macro ensures that `name` points to a stack-allocated + * FunctionCallInfoBaseData struct with sufficient space for `nargs` arguments. + */ +#define LOCAL_FCINFO(name, nargs) \ + /* use union with FunctionCallInfoBaseData to guarantee alignment */ \ + union \ + { \ + FunctionCallInfoBaseData fcinfo; \ + /* ensure enough space for nargs args is available */ \ + char fcinfo_data[SizeForFunctionCallInfo(nargs)]; \ + } name##data; \ + FunctionCallInfo name = &name##data.fcinfo + +/* + * This routine fills a FmgrInfo struct, given the OID + * of the function to be called. + */ +extern void fmgr_info(Oid functionId, FmgrInfo *finfo); + +/* + * Same, when the FmgrInfo struct is in a memory context longer-lived than + * CurrentMemoryContext. The specified context will be set as fn_mcxt + * and used to hold all subsidiary data of finfo. + */ +extern void fmgr_info_cxt(Oid functionId, FmgrInfo *finfo, + MemoryContext mcxt); + +/* Convenience macro for setting the fn_expr field */ +#define fmgr_info_set_expr(expr, finfo) \ + ((finfo)->fn_expr = (expr)) + +/* + * Copy an FmgrInfo struct + */ +extern void fmgr_info_copy(FmgrInfo *dstinfo, FmgrInfo *srcinfo, + MemoryContext destcxt); + +extern void fmgr_symbol(Oid functionId, char **mod, char **fn); + +/* + * This macro initializes all the fields of a FunctionCallInfoBaseData except + * for the args[] array. + */ +#define InitFunctionCallInfoData(Fcinfo, Flinfo, Nargs, Collation, Context, Resultinfo) \ + do { \ + (Fcinfo).flinfo = (Flinfo); \ + (Fcinfo).context = (Context); \ + (Fcinfo).resultinfo = (Resultinfo); \ + (Fcinfo).fncollation = (Collation); \ + (Fcinfo).isnull = false; \ + (Fcinfo).nargs = (Nargs); \ + } while (0) + +/* + * This macro invokes a function given a filled-in FunctionCallInfoBaseData + * struct. The macro result is the returned Datum --- but note that + * caller must still check fcinfo->isnull! Also, if function is strict, + * it is caller's responsibility to verify that no null arguments are present + * before calling. + * + * Some code performs multiple calls without redoing InitFunctionCallInfoData, + * possibly altering the argument values. This is okay, but be sure to reset + * the fcinfo->isnull flag before each call, since callees are permitted to + * assume that starts out false. + */ +#define FunctionCallInvoke(fcinfo) ((* (fcinfo)->flinfo->fn_addr) (fcinfo)) + + +/*------------------------------------------------------------------------- + * Support macros to ease writing fmgr-compatible functions + * + * A C-coded fmgr-compatible function should be declared as + * + * Datum + * function_name(PG_FUNCTION_ARGS) + * { + * ... + * } + * + * It should access its arguments using appropriate PG_GETARG_xxx macros + * and should return its result using PG_RETURN_xxx. + * + *------------------------------------------------------------------------- + */ + +/* Standard parameter list for fmgr-compatible functions */ +#define PG_FUNCTION_ARGS FunctionCallInfo fcinfo + +/* + * Get collation function should use. + */ +#define PG_GET_COLLATION() (fcinfo->fncollation) + +/* + * Get number of arguments passed to function. + */ +#define PG_NARGS() (fcinfo->nargs) + +/* + * If function is not marked "proisstrict" in pg_proc, it must check for + * null arguments using this macro. Do not try to GETARG a null argument! + */ +#define PG_ARGISNULL(n) (fcinfo->args[n].isnull) + +/* + * Support for fetching detoasted copies of toastable datatypes (all of + * which are varlena types). pg_detoast_datum() gives you either the input + * datum (if not toasted) or a detoasted copy allocated with palloc(). + * pg_detoast_datum_copy() always gives you a palloc'd copy --- use it + * if you need a modifiable copy of the input. Caller is expected to have + * checked for null inputs first, if necessary. + * + * pg_detoast_datum_packed() will return packed (1-byte header) datums + * unmodified. It will still expand an externally toasted or compressed datum. + * The resulting datum can be accessed using VARSIZE_ANY() and VARDATA_ANY() + * (beware of multiple evaluations in those macros!) + * + * In consumers oblivious to data alignment, call PG_DETOAST_DATUM_PACKED(), + * VARDATA_ANY(), VARSIZE_ANY() and VARSIZE_ANY_EXHDR(). Elsewhere, call + * PG_DETOAST_DATUM(), VARDATA() and VARSIZE(). Directly fetching an int16, + * int32 or wider field in the struct representing the datum layout requires + * aligned data. memcpy() is alignment-oblivious, as are most operations on + * datatypes, such as text, whose layout struct contains only char fields. + * + * Note: it'd be nice if these could be macros, but I see no way to do that + * without evaluating the arguments multiple times, which is NOT acceptable. + */ +extern struct varlena *pg_detoast_datum(struct varlena *datum); +extern struct varlena *pg_detoast_datum_copy(struct varlena *datum); +extern struct varlena *pg_detoast_datum_slice(struct varlena *datum, + int32 first, int32 count); +extern struct varlena *pg_detoast_datum_packed(struct varlena *datum); + +#define PG_DETOAST_DATUM(datum) \ + pg_detoast_datum((struct varlena *) DatumGetPointer(datum)) +#define PG_DETOAST_DATUM_COPY(datum) \ + pg_detoast_datum_copy((struct varlena *) DatumGetPointer(datum)) +#define PG_DETOAST_DATUM_SLICE(datum,f,c) \ + pg_detoast_datum_slice((struct varlena *) DatumGetPointer(datum), \ + (int32) (f), (int32) (c)) +/* WARNING -- unaligned pointer */ +#define PG_DETOAST_DATUM_PACKED(datum) \ + pg_detoast_datum_packed((struct varlena *) DatumGetPointer(datum)) + +/* + * Support for cleaning up detoasted copies of inputs. This must only + * be used for pass-by-ref datatypes, and normally would only be used + * for toastable types. If the given pointer is different from the + * original argument, assume it's a palloc'd detoasted copy, and pfree it. + * NOTE: most functions on toastable types do not have to worry about this, + * but we currently require that support functions for indexes not leak + * memory. + */ +#define PG_FREE_IF_COPY(ptr,n) \ + do { \ + if ((Pointer) (ptr) != PG_GETARG_POINTER(n)) \ + pfree(ptr); \ + } while (0) + +/* Macros for fetching arguments of standard types */ + +#define PG_GETARG_DATUM(n) (fcinfo->args[n].value) +#define PG_GETARG_INT32(n) DatumGetInt32(PG_GETARG_DATUM(n)) +#define PG_GETARG_UINT32(n) DatumGetUInt32(PG_GETARG_DATUM(n)) +#define PG_GETARG_INT16(n) DatumGetInt16(PG_GETARG_DATUM(n)) +#define PG_GETARG_UINT16(n) DatumGetUInt16(PG_GETARG_DATUM(n)) +#define PG_GETARG_CHAR(n) DatumGetChar(PG_GETARG_DATUM(n)) +#define PG_GETARG_BOOL(n) DatumGetBool(PG_GETARG_DATUM(n)) +#define PG_GETARG_OID(n) DatumGetObjectId(PG_GETARG_DATUM(n)) +#define PG_GETARG_POINTER(n) DatumGetPointer(PG_GETARG_DATUM(n)) +#define PG_GETARG_CSTRING(n) DatumGetCString(PG_GETARG_DATUM(n)) +#define PG_GETARG_NAME(n) DatumGetName(PG_GETARG_DATUM(n)) +#define PG_GETARG_TRANSACTIONID(n) DatumGetTransactionId(PG_GETARG_DATUM(n)) +/* these macros hide the pass-by-reference-ness of the datatype: */ +#define PG_GETARG_FLOAT4(n) DatumGetFloat4(PG_GETARG_DATUM(n)) +#define PG_GETARG_FLOAT8(n) DatumGetFloat8(PG_GETARG_DATUM(n)) +#define PG_GETARG_INT64(n) DatumGetInt64(PG_GETARG_DATUM(n)) +/* use this if you want the raw, possibly-toasted input datum: */ +#define PG_GETARG_RAW_VARLENA_P(n) ((struct varlena *) PG_GETARG_POINTER(n)) +/* use this if you want the input datum de-toasted: */ +#define PG_GETARG_VARLENA_P(n) PG_DETOAST_DATUM(PG_GETARG_DATUM(n)) +/* and this if you can handle 1-byte-header datums: */ +#define PG_GETARG_VARLENA_PP(n) PG_DETOAST_DATUM_PACKED(PG_GETARG_DATUM(n)) +/* DatumGetFoo macros for varlena types will typically look like this: */ +#define DatumGetByteaPP(X) ((bytea *) PG_DETOAST_DATUM_PACKED(X)) +#define DatumGetTextPP(X) ((text *) PG_DETOAST_DATUM_PACKED(X)) +#define DatumGetBpCharPP(X) ((BpChar *) PG_DETOAST_DATUM_PACKED(X)) +#define DatumGetVarCharPP(X) ((VarChar *) PG_DETOAST_DATUM_PACKED(X)) +#define DatumGetHeapTupleHeader(X) ((HeapTupleHeader) PG_DETOAST_DATUM(X)) +/* And we also offer variants that return an OK-to-write copy */ +#define DatumGetByteaPCopy(X) ((bytea *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetTextPCopy(X) ((text *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetBpCharPCopy(X) ((BpChar *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetVarCharPCopy(X) ((VarChar *) PG_DETOAST_DATUM_COPY(X)) +#define DatumGetHeapTupleHeaderCopy(X) ((HeapTupleHeader) PG_DETOAST_DATUM_COPY(X)) +/* Variants which return n bytes starting at pos. m */ +#define DatumGetByteaPSlice(X,m,n) ((bytea *) PG_DETOAST_DATUM_SLICE(X,m,n)) +#define DatumGetTextPSlice(X,m,n) ((text *) PG_DETOAST_DATUM_SLICE(X,m,n)) +#define DatumGetBpCharPSlice(X,m,n) ((BpChar *) PG_DETOAST_DATUM_SLICE(X,m,n)) +#define DatumGetVarCharPSlice(X,m,n) ((VarChar *) PG_DETOAST_DATUM_SLICE(X,m,n)) +/* GETARG macros for varlena types will typically look like this: */ +#define PG_GETARG_BYTEA_PP(n) DatumGetByteaPP(PG_GETARG_DATUM(n)) +#define PG_GETARG_TEXT_PP(n) DatumGetTextPP(PG_GETARG_DATUM(n)) +#define PG_GETARG_BPCHAR_PP(n) DatumGetBpCharPP(PG_GETARG_DATUM(n)) +#define PG_GETARG_VARCHAR_PP(n) DatumGetVarCharPP(PG_GETARG_DATUM(n)) +#define PG_GETARG_HEAPTUPLEHEADER(n) DatumGetHeapTupleHeader(PG_GETARG_DATUM(n)) +/* And we also offer variants that return an OK-to-write copy */ +#define PG_GETARG_BYTEA_P_COPY(n) DatumGetByteaPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_TEXT_P_COPY(n) DatumGetTextPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_BPCHAR_P_COPY(n) DatumGetBpCharPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_VARCHAR_P_COPY(n) DatumGetVarCharPCopy(PG_GETARG_DATUM(n)) +#define PG_GETARG_HEAPTUPLEHEADER_COPY(n) DatumGetHeapTupleHeaderCopy(PG_GETARG_DATUM(n)) +/* And a b-byte slice from position a -also OK to write */ +#define PG_GETARG_BYTEA_P_SLICE(n,a,b) DatumGetByteaPSlice(PG_GETARG_DATUM(n),a,b) +#define PG_GETARG_TEXT_P_SLICE(n,a,b) DatumGetTextPSlice(PG_GETARG_DATUM(n),a,b) +#define PG_GETARG_BPCHAR_P_SLICE(n,a,b) DatumGetBpCharPSlice(PG_GETARG_DATUM(n),a,b) +#define PG_GETARG_VARCHAR_P_SLICE(n,a,b) DatumGetVarCharPSlice(PG_GETARG_DATUM(n),a,b) +/* + * Obsolescent variants that guarantee INT alignment for the return value. + * Few operations on these particular types need alignment, mainly operations + * that cast the VARDATA pointer to a type like int16[]. Most code should use + * the ...PP(X) counterpart. Nonetheless, these appear frequently in code + * predating the PostgreSQL 8.3 introduction of the ...PP(X) variants. + */ +#define DatumGetByteaP(X) ((bytea *) PG_DETOAST_DATUM(X)) +#define DatumGetTextP(X) ((text *) PG_DETOAST_DATUM(X)) +#define DatumGetBpCharP(X) ((BpChar *) PG_DETOAST_DATUM(X)) +#define DatumGetVarCharP(X) ((VarChar *) PG_DETOAST_DATUM(X)) +#define PG_GETARG_BYTEA_P(n) DatumGetByteaP(PG_GETARG_DATUM(n)) +#define PG_GETARG_TEXT_P(n) DatumGetTextP(PG_GETARG_DATUM(n)) +#define PG_GETARG_BPCHAR_P(n) DatumGetBpCharP(PG_GETARG_DATUM(n)) +#define PG_GETARG_VARCHAR_P(n) DatumGetVarCharP(PG_GETARG_DATUM(n)) + +/* To access options from opclass support functions use this: */ +#define PG_HAS_OPCLASS_OPTIONS() has_fn_opclass_options(fcinfo->flinfo) +#define PG_GET_OPCLASS_OPTIONS() get_fn_opclass_options(fcinfo->flinfo) + +/* To return a NULL do this: */ +#define PG_RETURN_NULL() \ + do { fcinfo->isnull = true; return (Datum) 0; } while (0) + +/* A few internal functions return void (which is not the same as NULL!) */ +#define PG_RETURN_VOID() return (Datum) 0 + +/* Macros for returning results of standard types */ + +#define PG_RETURN_DATUM(x) return (x) +#define PG_RETURN_INT32(x) return Int32GetDatum(x) +#define PG_RETURN_UINT32(x) return UInt32GetDatum(x) +#define PG_RETURN_INT16(x) return Int16GetDatum(x) +#define PG_RETURN_UINT16(x) return UInt16GetDatum(x) +#define PG_RETURN_CHAR(x) return CharGetDatum(x) +#define PG_RETURN_BOOL(x) return BoolGetDatum(x) +#define PG_RETURN_OID(x) return ObjectIdGetDatum(x) +#define PG_RETURN_POINTER(x) return PointerGetDatum(x) +#define PG_RETURN_CSTRING(x) return CStringGetDatum(x) +#define PG_RETURN_NAME(x) return NameGetDatum(x) +#define PG_RETURN_TRANSACTIONID(x) return TransactionIdGetDatum(x) +/* these macros hide the pass-by-reference-ness of the datatype: */ +#define PG_RETURN_FLOAT4(x) return Float4GetDatum(x) +#define PG_RETURN_FLOAT8(x) return Float8GetDatum(x) +#define PG_RETURN_INT64(x) return Int64GetDatum(x) +#define PG_RETURN_UINT64(x) return UInt64GetDatum(x) +/* RETURN macros for other pass-by-ref types will typically look like this: */ +#define PG_RETURN_BYTEA_P(x) PG_RETURN_POINTER(x) +#define PG_RETURN_TEXT_P(x) PG_RETURN_POINTER(x) +#define PG_RETURN_BPCHAR_P(x) PG_RETURN_POINTER(x) +#define PG_RETURN_VARCHAR_P(x) PG_RETURN_POINTER(x) +#define PG_RETURN_HEAPTUPLEHEADER(x) return HeapTupleHeaderGetDatum(x) + + +/*------------------------------------------------------------------------- + * Support for detecting call convention of dynamically-loaded functions + * + * Dynamically loaded functions currently can only use the version-1 ("new + * style") calling convention. Version-0 ("old style") is not supported + * anymore. Version 1 is the call convention defined in this header file, and + * must be accompanied by the macro call + * + * PG_FUNCTION_INFO_V1(function_name); + * + * Note that internal functions do not need this decoration since they are + * assumed to be version-1. + * + *------------------------------------------------------------------------- + */ + +typedef struct +{ + int api_version; /* specifies call convention version number */ + /* More fields may be added later, for version numbers > 1. */ +} Pg_finfo_record; + +/* Expected signature of an info function */ +typedef const Pg_finfo_record *(*PGFInfoFunction) (void); + +/* + * Macro to build an info function associated with the given function name. + * + * As a convenience, also provide an "extern" declaration for the given + * function name, so that writers of C functions need not write that too. + * + * On Windows, the function and info function must be exported. Our normal + * build processes take care of that via .DEF files or --export-all-symbols. + * Module authors using a different build process might need to manually + * declare the function PGDLLEXPORT. We do that automatically here for the + * info function, since authors shouldn't need to be explicitly aware of it. + */ +#define PG_FUNCTION_INFO_V1(funcname) \ +extern PGDLLEXPORT Datum funcname(PG_FUNCTION_ARGS); \ +extern PGDLLEXPORT const Pg_finfo_record * CppConcat(pg_finfo_,funcname)(void); \ +const Pg_finfo_record * \ +CppConcat(pg_finfo_,funcname) (void) \ +{ \ + static const Pg_finfo_record my_finfo = { 1 }; \ + return &my_finfo; \ +} \ +extern int no_such_variable + + +/* + * Declare _PG_init/_PG_fini centrally. Historically each shared library had + * its own declaration; but now that we want to mark these PGDLLEXPORT, using + * central declarations avoids each extension having to add that. Any + * existing declarations in extensions will continue to work if fmgr.h is + * included before them, otherwise compilation for Windows will fail. + */ +extern PGDLLEXPORT void _PG_init(void); +extern PGDLLEXPORT void _PG_fini(void); + + +/*------------------------------------------------------------------------- + * Support for verifying backend compatibility of loaded modules + * + * We require dynamically-loaded modules to include the macro call + * PG_MODULE_MAGIC; + * so that we can check for obvious incompatibility, such as being compiled + * for a different major PostgreSQL version. + * + * To compile with versions of PostgreSQL that do not support this, + * you may put an #ifdef/#endif test around it. Note that in a multiple- + * source-file module, the macro call should only appear once. + * + * The specific items included in the magic block are intended to be ones that + * are custom-configurable and especially likely to break dynamically loaded + * modules if they were compiled with other values. Also, the length field + * can be used to detect definition changes. + * + * Note: we compare magic blocks with memcmp(), so there had better not be + * any alignment pad bytes in them. + * + * Note: when changing the contents of magic blocks, be sure to adjust the + * incompatible_module_error() function in dfmgr.c. + *------------------------------------------------------------------------- + */ + +/* Definition of the magic block structure */ +typedef struct +{ + int len; /* sizeof(this struct) */ + int version; /* PostgreSQL major version */ + int funcmaxargs; /* FUNC_MAX_ARGS */ + int indexmaxkeys; /* INDEX_MAX_KEYS */ + int namedatalen; /* NAMEDATALEN */ + int float8byval; /* FLOAT8PASSBYVAL */ + char abi_extra[32]; /* see pg_config_manual.h */ +} Pg_magic_struct; + +/* The actual data block contents */ +#define PG_MODULE_MAGIC_DATA \ +{ \ + sizeof(Pg_magic_struct), \ + PG_VERSION_NUM / 100, \ + FUNC_MAX_ARGS, \ + INDEX_MAX_KEYS, \ + NAMEDATALEN, \ + FLOAT8PASSBYVAL, \ + FMGR_ABI_EXTRA, \ +} + +StaticAssertDecl(sizeof(FMGR_ABI_EXTRA) <= sizeof(((Pg_magic_struct *) 0)->abi_extra), + "FMGR_ABI_EXTRA too long"); + +/* + * Declare the module magic function. It needs to be a function as the dlsym + * in the backend is only guaranteed to work on functions, not data + */ +typedef const Pg_magic_struct *(*PGModuleMagicFunction) (void); + +#define PG_MAGIC_FUNCTION_NAME Pg_magic_func +#define PG_MAGIC_FUNCTION_NAME_STRING "Pg_magic_func" + +#define PG_MODULE_MAGIC \ +extern PGDLLEXPORT const Pg_magic_struct *PG_MAGIC_FUNCTION_NAME(void); \ +const Pg_magic_struct * \ +PG_MAGIC_FUNCTION_NAME(void) \ +{ \ + static const Pg_magic_struct Pg_magic_data = PG_MODULE_MAGIC_DATA; \ + return &Pg_magic_data; \ +} \ +extern int no_such_variable + + +/*------------------------------------------------------------------------- + * Support routines and macros for callers of fmgr-compatible functions + *------------------------------------------------------------------------- + */ + +/* These are for invocation of a specifically named function with a + * directly-computed parameter list. Note that neither arguments nor result + * are allowed to be NULL. Also, the function cannot be one that needs to + * look at FmgrInfo, since there won't be any. + */ +extern Datum DirectFunctionCall1Coll(PGFunction func, Oid collation, + Datum arg1); +extern Datum DirectFunctionCall2Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2); +extern Datum DirectFunctionCall3Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3); +extern Datum DirectFunctionCall4Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4); +extern Datum DirectFunctionCall5Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5); +extern Datum DirectFunctionCall6Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6); +extern Datum DirectFunctionCall7Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7); +extern Datum DirectFunctionCall8Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7, Datum arg8); +extern Datum DirectFunctionCall9Coll(PGFunction func, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7, Datum arg8, + Datum arg9); + +/* + * These functions work like the DirectFunctionCall functions except that + * they use the flinfo parameter to initialise the fcinfo for the call. + * It's recommended that the callee only use the fn_extra and fn_mcxt + * fields, as other fields will typically describe the calling function + * not the callee. Conversely, the calling function should not have + * used fn_extra, unless its use is known to be compatible with the callee's. + */ +extern Datum CallerFInfoFunctionCall1(PGFunction func, FmgrInfo *flinfo, + Oid collation, Datum arg1); +extern Datum CallerFInfoFunctionCall2(PGFunction func, FmgrInfo *flinfo, + Oid collation, Datum arg1, Datum arg2); + +/* These are for invocation of a previously-looked-up function with a + * directly-computed parameter list. Note that neither arguments nor result + * are allowed to be NULL. + */ +extern Datum FunctionCall0Coll(FmgrInfo *flinfo, Oid collation); +extern Datum FunctionCall1Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1); +extern Datum FunctionCall2Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2); +extern Datum FunctionCall3Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3); +extern Datum FunctionCall4Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4); +extern Datum FunctionCall5Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5); +extern Datum FunctionCall6Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6); +extern Datum FunctionCall7Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7); +extern Datum FunctionCall8Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7, Datum arg8); +extern Datum FunctionCall9Coll(FmgrInfo *flinfo, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7, Datum arg8, + Datum arg9); + +/* These are for invocation of a function identified by OID with a + * directly-computed parameter list. Note that neither arguments nor result + * are allowed to be NULL. These are essentially fmgr_info() followed by + * FunctionCallN(). If the same function is to be invoked repeatedly, do the + * fmgr_info() once and then use FunctionCallN(). + */ +extern Datum OidFunctionCall0Coll(Oid functionId, Oid collation); +extern Datum OidFunctionCall1Coll(Oid functionId, Oid collation, + Datum arg1); +extern Datum OidFunctionCall2Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2); +extern Datum OidFunctionCall3Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3); +extern Datum OidFunctionCall4Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4); +extern Datum OidFunctionCall5Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5); +extern Datum OidFunctionCall6Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6); +extern Datum OidFunctionCall7Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7); +extern Datum OidFunctionCall8Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7, Datum arg8); +extern Datum OidFunctionCall9Coll(Oid functionId, Oid collation, + Datum arg1, Datum arg2, + Datum arg3, Datum arg4, Datum arg5, + Datum arg6, Datum arg7, Datum arg8, + Datum arg9); + +/* These macros allow the collation argument to be omitted (with a default of + * InvalidOid, ie, no collation). They exist mostly for backwards + * compatibility of source code. + */ +#define DirectFunctionCall1(func, arg1) \ + DirectFunctionCall1Coll(func, InvalidOid, arg1) +#define DirectFunctionCall2(func, arg1, arg2) \ + DirectFunctionCall2Coll(func, InvalidOid, arg1, arg2) +#define DirectFunctionCall3(func, arg1, arg2, arg3) \ + DirectFunctionCall3Coll(func, InvalidOid, arg1, arg2, arg3) +#define DirectFunctionCall4(func, arg1, arg2, arg3, arg4) \ + DirectFunctionCall4Coll(func, InvalidOid, arg1, arg2, arg3, arg4) +#define DirectFunctionCall5(func, arg1, arg2, arg3, arg4, arg5) \ + DirectFunctionCall5Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5) +#define DirectFunctionCall6(func, arg1, arg2, arg3, arg4, arg5, arg6) \ + DirectFunctionCall6Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6) +#define DirectFunctionCall7(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \ + DirectFunctionCall7Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7) +#define DirectFunctionCall8(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \ + DirectFunctionCall8Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) +#define DirectFunctionCall9(func, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \ + DirectFunctionCall9Coll(func, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) +#define FunctionCall1(flinfo, arg1) \ + FunctionCall1Coll(flinfo, InvalidOid, arg1) +#define FunctionCall2(flinfo, arg1, arg2) \ + FunctionCall2Coll(flinfo, InvalidOid, arg1, arg2) +#define FunctionCall3(flinfo, arg1, arg2, arg3) \ + FunctionCall3Coll(flinfo, InvalidOid, arg1, arg2, arg3) +#define FunctionCall4(flinfo, arg1, arg2, arg3, arg4) \ + FunctionCall4Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4) +#define FunctionCall5(flinfo, arg1, arg2, arg3, arg4, arg5) \ + FunctionCall5Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5) +#define FunctionCall6(flinfo, arg1, arg2, arg3, arg4, arg5, arg6) \ + FunctionCall6Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6) +#define FunctionCall7(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \ + FunctionCall7Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7) +#define FunctionCall8(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \ + FunctionCall8Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) +#define FunctionCall9(flinfo, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \ + FunctionCall9Coll(flinfo, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) +#define OidFunctionCall0(functionId) \ + OidFunctionCall0Coll(functionId, InvalidOid) +#define OidFunctionCall1(functionId, arg1) \ + OidFunctionCall1Coll(functionId, InvalidOid, arg1) +#define OidFunctionCall2(functionId, arg1, arg2) \ + OidFunctionCall2Coll(functionId, InvalidOid, arg1, arg2) +#define OidFunctionCall3(functionId, arg1, arg2, arg3) \ + OidFunctionCall3Coll(functionId, InvalidOid, arg1, arg2, arg3) +#define OidFunctionCall4(functionId, arg1, arg2, arg3, arg4) \ + OidFunctionCall4Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4) +#define OidFunctionCall5(functionId, arg1, arg2, arg3, arg4, arg5) \ + OidFunctionCall5Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5) +#define OidFunctionCall6(functionId, arg1, arg2, arg3, arg4, arg5, arg6) \ + OidFunctionCall6Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6) +#define OidFunctionCall7(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \ + OidFunctionCall7Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7) +#define OidFunctionCall8(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \ + OidFunctionCall8Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) +#define OidFunctionCall9(functionId, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \ + OidFunctionCall9Coll(functionId, InvalidOid, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) + + +/* Special cases for convenient invocation of datatype I/O functions. */ +extern Datum InputFunctionCall(FmgrInfo *flinfo, char *str, + Oid typioparam, int32 typmod); +extern bool InputFunctionCallSafe(FmgrInfo *flinfo, char *str, + Oid typioparam, int32 typmod, + fmNodePtr escontext, + Datum *result); +extern bool DirectInputFunctionCallSafe(PGFunction func, char *str, + Oid typioparam, int32 typmod, + fmNodePtr escontext, + Datum *result); +extern Datum OidInputFunctionCall(Oid functionId, char *str, + Oid typioparam, int32 typmod); +extern char *OutputFunctionCall(FmgrInfo *flinfo, Datum val); +extern char *OidOutputFunctionCall(Oid functionId, Datum val); +extern Datum ReceiveFunctionCall(FmgrInfo *flinfo, fmStringInfo buf, + Oid typioparam, int32 typmod); +extern Datum OidReceiveFunctionCall(Oid functionId, fmStringInfo buf, + Oid typioparam, int32 typmod); +extern bytea *SendFunctionCall(FmgrInfo *flinfo, Datum val); +extern bytea *OidSendFunctionCall(Oid functionId, Datum val); + + +/* + * Routines in fmgr.c + */ +extern const Pg_finfo_record *fetch_finfo_record(void *filehandle, const char *funcname); +extern Oid fmgr_internal_function(const char *proname); +extern Oid get_fn_expr_rettype(FmgrInfo *flinfo); +extern Oid get_fn_expr_argtype(FmgrInfo *flinfo, int argnum); +extern Oid get_call_expr_argtype(fmNodePtr expr, int argnum); +extern bool get_fn_expr_arg_stable(FmgrInfo *flinfo, int argnum); +extern bool get_call_expr_arg_stable(fmNodePtr expr, int argnum); +extern bool get_fn_expr_variadic(FmgrInfo *flinfo); +extern bytea *get_fn_opclass_options(FmgrInfo *flinfo); +extern bool has_fn_opclass_options(FmgrInfo *flinfo); +extern void set_fn_opclass_options(FmgrInfo *flinfo, bytea *options); +extern bool CheckFunctionValidatorAccess(Oid validatorOid, Oid functionOid); + +/* + * Routines in dfmgr.c + */ +extern PGDLLIMPORT char *Dynamic_library_path; + +extern void *load_external_function(const char *filename, const char *funcname, + bool signalNotFound, void **filehandle); +extern void *lookup_external_function(void *filehandle, const char *funcname); +extern void load_file(const char *filename, bool restricted); +extern void **find_rendezvous_variable(const char *varName); +extern Size EstimateLibraryStateSpace(void); +extern void SerializeLibraryState(Size maxsize, char *start_address); +extern void RestoreLibraryState(char *start_address); + +/* + * Support for aggregate functions + * + * These are actually in executor/nodeAgg.c, but we declare them here since + * the whole point is for callers to not be overly friendly with nodeAgg. + */ + +/* AggCheckCallContext can return one of the following codes, or 0: */ +#define AGG_CONTEXT_AGGREGATE 1 /* regular aggregate */ +#define AGG_CONTEXT_WINDOW 2 /* window function */ + +extern int AggCheckCallContext(FunctionCallInfo fcinfo, + MemoryContext *aggcontext); +extern fmAggrefPtr AggGetAggref(FunctionCallInfo fcinfo); +extern MemoryContext AggGetTempMemoryContext(FunctionCallInfo fcinfo); +extern bool AggStateIsShared(FunctionCallInfo fcinfo); +extern void AggRegisterCallback(FunctionCallInfo fcinfo, + fmExprContextCallbackFunction func, + Datum arg); + +/* + * We allow plugin modules to hook function entry/exit. This is intended + * as support for loadable security policy modules, which may want to + * perform additional privilege checks on function entry or exit, or to do + * other internal bookkeeping. To make this possible, such modules must be + * able not only to support normal function entry and exit, but also to trap + * the case where we bail out due to an error; and they must also be able to + * prevent inlining. + */ +typedef enum FmgrHookEventType +{ + FHET_START, + FHET_END, + FHET_ABORT +} FmgrHookEventType; + +typedef bool (*needs_fmgr_hook_type) (Oid fn_oid); + +typedef void (*fmgr_hook_type) (FmgrHookEventType event, + FmgrInfo *flinfo, Datum *arg); + +extern PGDLLIMPORT needs_fmgr_hook_type needs_fmgr_hook; +extern PGDLLIMPORT fmgr_hook_type fmgr_hook; + +#define FmgrHookIsNeeded(fn_oid) \ + (!needs_fmgr_hook ? false : (*needs_fmgr_hook)(fn_oid)) + +#endif /* FMGR_H */ |