postgresql/src/include/postgres.h
Alvaro Herrera 0ac5ad5134 Improve concurrency of foreign key locking
This patch introduces two additional lock modes for tuples: "SELECT FOR
KEY SHARE" and "SELECT FOR NO KEY UPDATE".  These don't block each
other, in contrast with already existing "SELECT FOR SHARE" and "SELECT
FOR UPDATE".  UPDATE commands that do not modify the values stored in
the columns that are part of the key of the tuple now grab a SELECT FOR
NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently
with tuple locks of the FOR KEY SHARE variety.

Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this
means the concurrency improvement applies to them, which is the whole
point of this patch.

The added tuple lock semantics require some rejiggering of the multixact
module, so that the locking level that each transaction is holding can
be stored alongside its Xid.  Also, multixacts now need to persist
across server restarts and crashes, because they can now represent not
only tuple locks, but also tuple updates.  This means we need more
careful tracking of lifetime of pg_multixact SLRU files; since they now
persist longer, we require more infrastructure to figure out when they
can be removed.  pg_upgrade also needs to be careful to copy
pg_multixact files over from the old server to the new, or at least part
of multixact.c state, depending on the versions of the old and new
servers.

Tuple time qualification rules (HeapTupleSatisfies routines) need to be
careful not to consider tuples with the "is multi" infomask bit set as
being only locked; they might need to look up MultiXact values (i.e.
possibly do pg_multixact I/O) to find out the Xid that updated a tuple,
whereas they previously were assured to only use information readily
available from the tuple header.  This is considered acceptable, because
the extra I/O would involve cases that would previously cause some
commands to block waiting for concurrent transactions to finish.

Another important change is the fact that locking tuples that have
previously been updated causes the future versions to be marked as
locked, too; this is essential for correctness of foreign key checks.
This causes additional WAL-logging, also (there was previously a single
WAL record for a locked tuple; now there are as many as updated copies
of the tuple there exist.)

With all this in place, contention related to tuples being checked by
foreign key rules should be much reduced.

As a bonus, the old behavior that a subtransaction grabbing a stronger
tuple lock than the parent (sub)transaction held on a given tuple and
later aborting caused the weaker lock to be lost, has been fixed.

Many new spec files were added for isolation tester framework, to ensure
overall behavior is sane.  There's probably room for several more tests.

There were several reviewers of this patch; in particular, Noah Misch
and Andres Freund spent considerable time in it.  Original idea for the
patch came from Simon Riggs, after a problem report by Joel Jacobson.
Most code is from me, with contributions from Marti Raudsepp, Alexander
Shulgin, Noah Misch and Andres Freund.

This patch was discussed in several pgsql-hackers threads; the most
important start at the following message-ids:
	AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com
	1290721684-sup-3951@alvh.no-ip.org
	1294953201-sup-2099@alvh.no-ip.org
	1320343602-sup-2290@alvh.no-ip.org
	1339690386-sup-8927@alvh.no-ip.org
	4FE5FF020200002500048A3D@gw.wicourts.gov
	4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 12:04:59 -03:00

698 lines
20 KiB
C

/*-------------------------------------------------------------------------
*
* postgres.h
* Primary include file for PostgreSQL server .c files
*
* This should be the first file included by PostgreSQL backend modules.
* Client-side code should include postgres_fe.h instead.
*
*
* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
* Portions Copyright (c) 1995, Regents of the University of California
*
* src/include/postgres.h
*
*-------------------------------------------------------------------------
*/
/*
*----------------------------------------------------------------
* TABLE OF CONTENTS
*
* When adding stuff to this file, please try to put stuff
* into the relevant section, or add new sections as appropriate.
*
* section description
* ------- ------------------------------------------------
* 1) variable-length datatypes (TOAST support)
* 2) datum type + support macros
* 3) exception handling definitions
*
* NOTES
*
* In general, this file should contain declarations that are widely needed
* in the backend environment, but are of no interest outside the backend.
*
* Simple type definitions live in c.h, where they are shared with
* postgres_fe.h. We do that since those type definitions are needed by
* frontend modules that want to deal with binary data transmission to or
* from the backend. Type definitions in this file should be for
* representations that never escape the backend, such as Datum or
* TOASTed varlena objects.
*
*----------------------------------------------------------------
*/
#ifndef POSTGRES_H
#define POSTGRES_H
#include "c.h"
#include "utils/elog.h"
#include "utils/palloc.h"
/* ----------------------------------------------------------------
* Section 1: variable-length datatypes (TOAST support)
* ----------------------------------------------------------------
*/
/*
* struct varatt_external is a "TOAST pointer", that is, the information
* needed to fetch a stored-out-of-line Datum. The data is compressed
* if and only if va_extsize < va_rawsize - VARHDRSZ. This struct must not
* contain any padding, because we sometimes compare pointers using memcmp.
*
* Note that this information is stored unaligned within actual tuples, so
* you need to memcpy from the tuple into a local struct variable before
* you can look at these fields! (The reason we use memcmp is to avoid
* having to do that just to detect equality of two TOAST pointers...)
*/
struct varatt_external
{
int32 va_rawsize; /* Original data size (includes header) */
int32 va_extsize; /* External saved size (doesn't) */
Oid va_valueid; /* Unique ID of value within TOAST table */
Oid va_toastrelid; /* RelID of TOAST table containing it */
};
/*
* These structs describe the header of a varlena object that may have been
* TOASTed. Generally, don't reference these structs directly, but use the
* macros below.
*
* We use separate structs for the aligned and unaligned cases because the
* compiler might otherwise think it could generate code that assumes
* alignment while touching fields of a 1-byte-header varlena.
*/
typedef union
{
struct /* Normal varlena (4-byte length) */
{
uint32 va_header;
char va_data[1];
} va_4byte;
struct /* Compressed-in-line format */
{
uint32 va_header;
uint32 va_rawsize; /* Original data size (excludes header) */
char va_data[1]; /* Compressed data */
} va_compressed;
} varattrib_4b;
typedef struct
{
uint8 va_header;
char va_data[1]; /* Data begins here */
} varattrib_1b;
typedef struct
{
uint8 va_header; /* Always 0x80 or 0x01 */
uint8 va_len_1be; /* Physical length of datum */
char va_data[1]; /* Data (for now always a TOAST pointer) */
} varattrib_1b_e;
/*
* Bit layouts for varlena headers on big-endian machines:
*
* 00xxxxxx 4-byte length word, aligned, uncompressed data (up to 1G)
* 01xxxxxx 4-byte length word, aligned, *compressed* data (up to 1G)
* 10000000 1-byte length word, unaligned, TOAST pointer
* 1xxxxxxx 1-byte length word, unaligned, uncompressed data (up to 126b)
*
* Bit layouts for varlena headers on little-endian machines:
*
* xxxxxx00 4-byte length word, aligned, uncompressed data (up to 1G)
* xxxxxx10 4-byte length word, aligned, *compressed* data (up to 1G)
* 00000001 1-byte length word, unaligned, TOAST pointer
* xxxxxxx1 1-byte length word, unaligned, uncompressed data (up to 126b)
*
* The "xxx" bits are the length field (which includes itself in all cases).
* In the big-endian case we mask to extract the length, in the little-endian
* case we shift. Note that in both cases the flag bits are in the physically
* first byte. Also, it is not possible for a 1-byte length word to be zero;
* this lets us disambiguate alignment padding bytes from the start of an
* unaligned datum. (We now *require* pad bytes to be filled with zero!)
*/
/*
* Endian-dependent macros. These are considered internal --- use the
* external macros below instead of using these directly.
*
* Note: IS_1B is true for external toast records but VARSIZE_1B will return 0
* for such records. Hence you should usually check for IS_EXTERNAL before
* checking for IS_1B.
*/
#ifdef WORDS_BIGENDIAN
#define VARATT_IS_4B(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0x80) == 0x00)
#define VARATT_IS_4B_U(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0xC0) == 0x00)
#define VARATT_IS_4B_C(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0xC0) == 0x40)
#define VARATT_IS_1B(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0x80) == 0x80)
#define VARATT_IS_1B_E(PTR) \
((((varattrib_1b *) (PTR))->va_header) == 0x80)
#define VARATT_NOT_PAD_BYTE(PTR) \
(*((uint8 *) (PTR)) != 0)
/* VARSIZE_4B() should only be used on known-aligned data */
#define VARSIZE_4B(PTR) \
(((varattrib_4b *) (PTR))->va_4byte.va_header & 0x3FFFFFFF)
#define VARSIZE_1B(PTR) \
(((varattrib_1b *) (PTR))->va_header & 0x7F)
#define VARSIZE_1B_E(PTR) \
(((varattrib_1b_e *) (PTR))->va_len_1be)
#define SET_VARSIZE_4B(PTR,len) \
(((varattrib_4b *) (PTR))->va_4byte.va_header = (len) & 0x3FFFFFFF)
#define SET_VARSIZE_4B_C(PTR,len) \
(((varattrib_4b *) (PTR))->va_4byte.va_header = ((len) & 0x3FFFFFFF) | 0x40000000)
#define SET_VARSIZE_1B(PTR,len) \
(((varattrib_1b *) (PTR))->va_header = (len) | 0x80)
#define SET_VARSIZE_1B_E(PTR,len) \
(((varattrib_1b_e *) (PTR))->va_header = 0x80, \
((varattrib_1b_e *) (PTR))->va_len_1be = (len))
#else /* !WORDS_BIGENDIAN */
#define VARATT_IS_4B(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0x01) == 0x00)
#define VARATT_IS_4B_U(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0x03) == 0x00)
#define VARATT_IS_4B_C(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0x03) == 0x02)
#define VARATT_IS_1B(PTR) \
((((varattrib_1b *) (PTR))->va_header & 0x01) == 0x01)
#define VARATT_IS_1B_E(PTR) \
((((varattrib_1b *) (PTR))->va_header) == 0x01)
#define VARATT_NOT_PAD_BYTE(PTR) \
(*((uint8 *) (PTR)) != 0)
/* VARSIZE_4B() should only be used on known-aligned data */
#define VARSIZE_4B(PTR) \
((((varattrib_4b *) (PTR))->va_4byte.va_header >> 2) & 0x3FFFFFFF)
#define VARSIZE_1B(PTR) \
((((varattrib_1b *) (PTR))->va_header >> 1) & 0x7F)
#define VARSIZE_1B_E(PTR) \
(((varattrib_1b_e *) (PTR))->va_len_1be)
#define SET_VARSIZE_4B(PTR,len) \
(((varattrib_4b *) (PTR))->va_4byte.va_header = (((uint32) (len)) << 2))
#define SET_VARSIZE_4B_C(PTR,len) \
(((varattrib_4b *) (PTR))->va_4byte.va_header = (((uint32) (len)) << 2) | 0x02)
#define SET_VARSIZE_1B(PTR,len) \
(((varattrib_1b *) (PTR))->va_header = (((uint8) (len)) << 1) | 0x01)
#define SET_VARSIZE_1B_E(PTR,len) \
(((varattrib_1b_e *) (PTR))->va_header = 0x01, \
((varattrib_1b_e *) (PTR))->va_len_1be = (len))
#endif /* WORDS_BIGENDIAN */
#define VARHDRSZ_SHORT 1
#define VARATT_SHORT_MAX 0x7F
#define VARATT_CAN_MAKE_SHORT(PTR) \
(VARATT_IS_4B_U(PTR) && \
(VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT) <= VARATT_SHORT_MAX)
#define VARATT_CONVERTED_SHORT_SIZE(PTR) \
(VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT)
#define VARHDRSZ_EXTERNAL 2
#define VARDATA_4B(PTR) (((varattrib_4b *) (PTR))->va_4byte.va_data)
#define VARDATA_4B_C(PTR) (((varattrib_4b *) (PTR))->va_compressed.va_data)
#define VARDATA_1B(PTR) (((varattrib_1b *) (PTR))->va_data)
#define VARDATA_1B_E(PTR) (((varattrib_1b_e *) (PTR))->va_data)
#define VARRAWSIZE_4B_C(PTR) \
(((varattrib_4b *) (PTR))->va_compressed.va_rawsize)
/* Externally visible macros */
/*
* VARDATA, VARSIZE, and SET_VARSIZE are the recommended API for most code
* for varlena datatypes. Note that they only work on untoasted,
* 4-byte-header Datums!
*
* Code that wants to use 1-byte-header values without detoasting should
* use VARSIZE_ANY/VARSIZE_ANY_EXHDR/VARDATA_ANY. The other macros here
* should usually be used only by tuple assembly/disassembly code and
* code that specifically wants to work with still-toasted Datums.
*
* WARNING: It is only safe to use VARDATA_ANY() -- typically with
* PG_DETOAST_DATUM_PACKED() -- if you really don't care about the alignment.
* Either because you're working with something like text where the alignment
* doesn't matter or because you're not going to access its constituent parts
* and just use things like memcpy on it anyways.
*/
#define VARDATA(PTR) VARDATA_4B(PTR)
#define VARSIZE(PTR) VARSIZE_4B(PTR)
#define VARSIZE_SHORT(PTR) VARSIZE_1B(PTR)
#define VARDATA_SHORT(PTR) VARDATA_1B(PTR)
#define VARSIZE_EXTERNAL(PTR) VARSIZE_1B_E(PTR)
#define VARDATA_EXTERNAL(PTR) VARDATA_1B_E(PTR)
#define VARATT_IS_COMPRESSED(PTR) VARATT_IS_4B_C(PTR)
#define VARATT_IS_EXTERNAL(PTR) VARATT_IS_1B_E(PTR)
#define VARATT_IS_SHORT(PTR) VARATT_IS_1B(PTR)
#define VARATT_IS_EXTENDED(PTR) (!VARATT_IS_4B_U(PTR))
#define SET_VARSIZE(PTR, len) SET_VARSIZE_4B(PTR, len)
#define SET_VARSIZE_SHORT(PTR, len) SET_VARSIZE_1B(PTR, len)
#define SET_VARSIZE_COMPRESSED(PTR, len) SET_VARSIZE_4B_C(PTR, len)
#define SET_VARSIZE_EXTERNAL(PTR, len) SET_VARSIZE_1B_E(PTR, len)
#define VARSIZE_ANY(PTR) \
(VARATT_IS_1B_E(PTR) ? VARSIZE_1B_E(PTR) : \
(VARATT_IS_1B(PTR) ? VARSIZE_1B(PTR) : \
VARSIZE_4B(PTR)))
#define VARSIZE_ANY_EXHDR(PTR) \
(VARATT_IS_1B_E(PTR) ? VARSIZE_1B_E(PTR)-VARHDRSZ_EXTERNAL : \
(VARATT_IS_1B(PTR) ? VARSIZE_1B(PTR)-VARHDRSZ_SHORT : \
VARSIZE_4B(PTR)-VARHDRSZ))
/* caution: this will not work on an external or compressed-in-line Datum */
/* caution: this will return a possibly unaligned pointer */
#define VARDATA_ANY(PTR) \
(VARATT_IS_1B(PTR) ? VARDATA_1B(PTR) : VARDATA_4B(PTR))
/* ----------------------------------------------------------------
* Section 2: datum type + support macros
* ----------------------------------------------------------------
*/
/*
* Port Notes:
* Postgres makes the following assumptions about datatype sizes:
*
* sizeof(Datum) == sizeof(void *) == 4 or 8
* sizeof(char) == 1
* sizeof(short) == 2
*
* When a type narrower than Datum is stored in a Datum, we place it in the
* low-order bits and are careful that the DatumGetXXX macro for it discards
* the unused high-order bits (as opposed to, say, assuming they are zero).
* This is needed to support old-style user-defined functions, since depending
* on architecture and compiler, the return value of a function returning char
* or short may contain garbage when called as if it returned Datum.
*/
typedef uintptr_t Datum;
#define SIZEOF_DATUM SIZEOF_VOID_P
typedef Datum *DatumPtr;
#define GET_1_BYTE(datum) (((Datum) (datum)) & 0x000000ff)
#define GET_2_BYTES(datum) (((Datum) (datum)) & 0x0000ffff)
#define GET_4_BYTES(datum) (((Datum) (datum)) & 0xffffffff)
#if SIZEOF_DATUM == 8
#define GET_8_BYTES(datum) ((Datum) (datum))
#endif
#define SET_1_BYTE(value) (((Datum) (value)) & 0x000000ff)
#define SET_2_BYTES(value) (((Datum) (value)) & 0x0000ffff)
#define SET_4_BYTES(value) (((Datum) (value)) & 0xffffffff)
#if SIZEOF_DATUM == 8
#define SET_8_BYTES(value) ((Datum) (value))
#endif
/*
* DatumGetBool
* Returns boolean value of a datum.
*
* Note: any nonzero value will be considered TRUE, but we ignore bits to
* the left of the width of bool, per comment above.
*/
#define DatumGetBool(X) ((bool) (((bool) (X)) != 0))
/*
* BoolGetDatum
* Returns datum representation for a boolean.
*
* Note: any nonzero value will be considered TRUE.
*/
#define BoolGetDatum(X) ((Datum) ((X) ? 1 : 0))
/*
* DatumGetChar
* Returns character value of a datum.
*/
#define DatumGetChar(X) ((char) GET_1_BYTE(X))
/*
* CharGetDatum
* Returns datum representation for a character.
*/
#define CharGetDatum(X) ((Datum) SET_1_BYTE(X))
/*
* Int8GetDatum
* Returns datum representation for an 8-bit integer.
*/
#define Int8GetDatum(X) ((Datum) SET_1_BYTE(X))
/*
* DatumGetUInt8
* Returns 8-bit unsigned integer value of a datum.
*/
#define DatumGetUInt8(X) ((uint8) GET_1_BYTE(X))
/*
* UInt8GetDatum
* Returns datum representation for an 8-bit unsigned integer.
*/
#define UInt8GetDatum(X) ((Datum) SET_1_BYTE(X))
/*
* DatumGetInt16
* Returns 16-bit integer value of a datum.
*/
#define DatumGetInt16(X) ((int16) GET_2_BYTES(X))
/*
* Int16GetDatum
* Returns datum representation for a 16-bit integer.
*/
#define Int16GetDatum(X) ((Datum) SET_2_BYTES(X))
/*
* DatumGetUInt16
* Returns 16-bit unsigned integer value of a datum.
*/
#define DatumGetUInt16(X) ((uint16) GET_2_BYTES(X))
/*
* UInt16GetDatum
* Returns datum representation for a 16-bit unsigned integer.
*/
#define UInt16GetDatum(X) ((Datum) SET_2_BYTES(X))
/*
* DatumGetInt32
* Returns 32-bit integer value of a datum.
*/
#define DatumGetInt32(X) ((int32) GET_4_BYTES(X))
/*
* Int32GetDatum
* Returns datum representation for a 32-bit integer.
*/
#define Int32GetDatum(X) ((Datum) SET_4_BYTES(X))
/*
* DatumGetUInt32
* Returns 32-bit unsigned integer value of a datum.
*/
#define DatumGetUInt32(X) ((uint32) GET_4_BYTES(X))
/*
* UInt32GetDatum
* Returns datum representation for a 32-bit unsigned integer.
*/
#define UInt32GetDatum(X) ((Datum) SET_4_BYTES(X))
/*
* DatumGetObjectId
* Returns object identifier value of a datum.
*/
#define DatumGetObjectId(X) ((Oid) GET_4_BYTES(X))
/*
* ObjectIdGetDatum
* Returns datum representation for an object identifier.
*/
#define ObjectIdGetDatum(X) ((Datum) SET_4_BYTES(X))
/*
* DatumGetTransactionId
* Returns transaction identifier value of a datum.
*/
#define DatumGetTransactionId(X) ((TransactionId) GET_4_BYTES(X))
/*
* TransactionIdGetDatum
* Returns datum representation for a transaction identifier.
*/
#define TransactionIdGetDatum(X) ((Datum) SET_4_BYTES((X)))
/*
* MultiXactIdGetDatum
* Returns datum representation for a multixact identifier.
*/
#define MultiXactIdGetDatum(X) ((Datum) SET_4_BYTES((X)))
/*
* DatumGetCommandId
* Returns command identifier value of a datum.
*/
#define DatumGetCommandId(X) ((CommandId) GET_4_BYTES(X))
/*
* CommandIdGetDatum
* Returns datum representation for a command identifier.
*/
#define CommandIdGetDatum(X) ((Datum) SET_4_BYTES(X))
/*
* DatumGetPointer
* Returns pointer value of a datum.
*/
#define DatumGetPointer(X) ((Pointer) (X))
/*
* PointerGetDatum
* Returns datum representation for a pointer.
*/
#define PointerGetDatum(X) ((Datum) (X))
/*
* DatumGetCString
* Returns C string (null-terminated string) value of a datum.
*
* Note: C string is not a full-fledged Postgres type at present,
* but type input functions use this conversion for their inputs.
*/
#define DatumGetCString(X) ((char *) DatumGetPointer(X))
/*
* CStringGetDatum
* Returns datum representation for a C string (null-terminated string).
*
* Note: C string is not a full-fledged Postgres type at present,
* but type output functions use this conversion for their outputs.
* Note: CString is pass-by-reference; caller must ensure the pointed-to
* value has adequate lifetime.
*/
#define CStringGetDatum(X) PointerGetDatum(X)
/*
* DatumGetName
* Returns name value of a datum.
*/
#define DatumGetName(X) ((Name) DatumGetPointer(X))
/*
* NameGetDatum
* Returns datum representation for a name.
*
* Note: Name is pass-by-reference; caller must ensure the pointed-to
* value has adequate lifetime.
*/
#define NameGetDatum(X) PointerGetDatum(X)
/*
* DatumGetInt64
* Returns 64-bit integer value of a datum.
*
* Note: this macro hides whether int64 is pass by value or by reference.
*/
#ifdef USE_FLOAT8_BYVAL
#define DatumGetInt64(X) ((int64) GET_8_BYTES(X))
#else
#define DatumGetInt64(X) (* ((int64 *) DatumGetPointer(X)))
#endif
/*
* Int64GetDatum
* Returns datum representation for a 64-bit integer.
*
* Note: if int64 is pass by reference, this function returns a reference
* to palloc'd space.
*/
#ifdef USE_FLOAT8_BYVAL
#define Int64GetDatum(X) ((Datum) SET_8_BYTES(X))
#else
extern Datum Int64GetDatum(int64 X);
#endif
/*
* DatumGetFloat4
* Returns 4-byte floating point value of a datum.
*
* Note: this macro hides whether float4 is pass by value or by reference.
*/
#ifdef USE_FLOAT4_BYVAL
extern float4 DatumGetFloat4(Datum X);
#else
#define DatumGetFloat4(X) (* ((float4 *) DatumGetPointer(X)))
#endif
/*
* Float4GetDatum
* Returns datum representation for a 4-byte floating point number.
*
* Note: if float4 is pass by reference, this function returns a reference
* to palloc'd space.
*/
extern Datum Float4GetDatum(float4 X);
/*
* DatumGetFloat8
* Returns 8-byte floating point value of a datum.
*
* Note: this macro hides whether float8 is pass by value or by reference.
*/
#ifdef USE_FLOAT8_BYVAL
extern float8 DatumGetFloat8(Datum X);
#else
#define DatumGetFloat8(X) (* ((float8 *) DatumGetPointer(X)))
#endif
/*
* Float8GetDatum
* Returns datum representation for an 8-byte floating point number.
*
* Note: if float8 is pass by reference, this function returns a reference
* to palloc'd space.
*/
extern Datum Float8GetDatum(float8 X);
/*
* Int64GetDatumFast
* Float8GetDatumFast
* Float4GetDatumFast
*
* These macros are intended to allow writing code that does not depend on
* whether int64, float8, float4 are pass-by-reference types, while not
* sacrificing performance when they are. The argument must be a variable
* that will exist and have the same value for as long as the Datum is needed.
* In the pass-by-ref case, the address of the variable is taken to use as
* the Datum. In the pass-by-val case, these will be the same as the non-Fast
* macros.
*/
#ifdef USE_FLOAT8_BYVAL
#define Int64GetDatumFast(X) Int64GetDatum(X)
#define Float8GetDatumFast(X) Float8GetDatum(X)
#else
#define Int64GetDatumFast(X) PointerGetDatum(&(X))
#define Float8GetDatumFast(X) PointerGetDatum(&(X))
#endif
#ifdef USE_FLOAT4_BYVAL
#define Float4GetDatumFast(X) Float4GetDatum(X)
#else
#define Float4GetDatumFast(X) PointerGetDatum(&(X))
#endif
/* ----------------------------------------------------------------
* Section 3: exception handling definitions
* Assert, Trap, etc macros
* ----------------------------------------------------------------
*/
extern PGDLLIMPORT bool assert_enabled;
/*
* USE_ASSERT_CHECKING, if defined, turns on all the assertions.
* - plai 9/5/90
*
* It should _NOT_ be defined in releases or in benchmark copies
*/
/*
* Trap
* Generates an exception if the given condition is true.
*/
#define Trap(condition, errorType) \
do { \
if ((assert_enabled) && (condition)) \
ExceptionalCondition(CppAsString(condition), (errorType), \
__FILE__, __LINE__); \
} while (0)
/*
* TrapMacro is the same as Trap but it's intended for use in macros:
*
* #define foo(x) (AssertMacro(x != 0), bar(x))
*
* Isn't CPP fun?
*/
#define TrapMacro(condition, errorType) \
((bool) ((! assert_enabled) || ! (condition) || \
(ExceptionalCondition(CppAsString(condition), (errorType), \
__FILE__, __LINE__), 0)))
#ifndef USE_ASSERT_CHECKING
#define Assert(condition)
#define AssertMacro(condition) ((void)true)
#define AssertArg(condition)
#define AssertState(condition)
#else
#define Assert(condition) \
Trap(!(condition), "FailedAssertion")
#define AssertMacro(condition) \
((void) TrapMacro(!(condition), "FailedAssertion"))
#define AssertArg(condition) \
Trap(!(condition), "BadArgument")
#define AssertState(condition) \
Trap(!(condition), "BadState")
#endif /* USE_ASSERT_CHECKING */
extern void ExceptionalCondition(const char *conditionName,
const char *errorType,
const char *fileName, int lineNumber) __attribute__((noreturn));
#endif /* POSTGRES_H */