1 /*-------------------------------------------------------------------------
4 * Primary include file for PostgreSQL server .c files
6 * This should be the first file included by PostgreSQL backend modules.
7 * Client-side code should include postgres_fe.h instead.
10 * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
11 * Portions Copyright (c) 1995, Regents of the University of California
13 * $Id: postgres.h,v 1.63 2003/04/06 22:45:23 petere Exp $
15 *-------------------------------------------------------------------------
18 *----------------------------------------------------------------
21 * When adding stuff to this file, please try to put stuff
22 * into the relevant section, or add new sections as appropriate.
25 * ------- ------------------------------------------------
26 * 1) variable-length datatypes (TOAST support)
27 * 2) datum type + support macros
28 * 3) exception handling definitions
29 * 4) genbki macros used by catalog/pg_xxx.h files
33 * In general, this file should contain declarations that are widely needed
34 * in the backend environment, but are of no interest outside the backend.
36 * Simple type definitions live in c.h, where they are shared with
37 * postgres_fe.h. We do that since those type definitions are needed by
38 * frontend modules that want to deal with binary data transmission to or
39 * from the backend. Type definitions in this file should be for
40 * representations that never escape the backend, such as Datum or
41 * TOASTed varlena objects.
43 *----------------------------------------------------------------
49 #include "utils/elog.h"
50 #include "utils/palloc.h"
52 /* ----------------------------------------------------------------
53 * Section 1: variable-length datatypes (TOAST support)
54 * ----------------------------------------------------------------
58 * struct varattrib is the header of a varlena object that may have been
62 #define TUPLE_TOASTER_ACTIVE
64 typedef struct varattrib
66 int32 va_header; /* External/compressed storage */
67 /* flags and item size */
72 int32 va_rawsize; /* Plain data size */
73 char va_data[1]; /* Compressed data */
74 } va_compressed; /* Compressed stored attribute */
78 int32 va_rawsize; /* Plain data size */
79 int32 va_extsize; /* External saved size */
80 Oid va_valueid; /* Unique identifier of value */
81 Oid va_toastrelid; /* RelID where to find chunks */
82 } va_external; /* External stored attribute */
84 char va_data[1]; /* Plain stored attribute */
88 #define VARATT_FLAG_EXTERNAL 0x80000000
89 #define VARATT_FLAG_COMPRESSED 0x40000000
90 #define VARATT_MASK_FLAGS 0xc0000000
91 #define VARATT_MASK_SIZE 0x3fffffff
93 #define VARATT_SIZEP(_PTR) (((varattrib *)(_PTR))->va_header)
94 #define VARATT_SIZE(PTR) (VARATT_SIZEP(PTR) & VARATT_MASK_SIZE)
95 #define VARATT_DATA(PTR) (((varattrib *)(PTR))->va_content.va_data)
96 #define VARATT_CDATA(PTR) (((varattrib *)(PTR))->va_content.va_compressed.va_data)
98 #define VARSIZE(__PTR) VARATT_SIZE(__PTR)
99 #define VARDATA(__PTR) VARATT_DATA(__PTR)
101 #define VARATT_IS_EXTENDED(PTR) \
102 ((VARATT_SIZEP(PTR) & VARATT_MASK_FLAGS) != 0)
103 #define VARATT_IS_EXTERNAL(PTR) \
104 ((VARATT_SIZEP(PTR) & VARATT_FLAG_EXTERNAL) != 0)
105 #define VARATT_IS_COMPRESSED(PTR) \
106 ((VARATT_SIZEP(PTR) & VARATT_FLAG_COMPRESSED) != 0)
109 /* ----------------------------------------------------------------
110 * Section 2: datum type + support macros
111 * ----------------------------------------------------------------
116 * Postgres makes the following assumption about machines:
118 * sizeof(Datum) == sizeof(long) >= sizeof(void *) >= 4
120 * Postgres also assumes that
128 * If your machine meets these requirements, Datums should also be checked
129 * to see if the positioning is correct.
132 typedef unsigned long Datum; /* XXX sizeof(long) >= sizeof(void *) */
133 #define SIZEOF_DATUM SIZEOF_UNSIGNED_LONG
134 typedef Datum *DatumPtr;
136 #define GET_1_BYTE(datum) (((Datum) (datum)) & 0x000000ff)
137 #define GET_2_BYTES(datum) (((Datum) (datum)) & 0x0000ffff)
138 #define GET_4_BYTES(datum) (((Datum) (datum)) & 0xffffffff)
139 #define SET_1_BYTE(value) (((Datum) (value)) & 0x000000ff)
140 #define SET_2_BYTES(value) (((Datum) (value)) & 0x0000ffff)
141 #define SET_4_BYTES(value) (((Datum) (value)) & 0xffffffff)
145 * Returns boolean value of a datum.
147 * Note: any nonzero value will be considered TRUE.
150 #define DatumGetBool(X) ((bool) (((Datum) (X)) != 0))
154 * Returns datum representation for a boolean.
156 * Note: any nonzero value will be considered TRUE.
159 #define BoolGetDatum(X) ((Datum) ((X) ? 1 : 0))
163 * Returns character value of a datum.
166 #define DatumGetChar(X) ((char) GET_1_BYTE(X))
170 * Returns datum representation for a character.
173 #define CharGetDatum(X) ((Datum) SET_1_BYTE(X))
177 * Returns datum representation for an 8-bit integer.
180 #define Int8GetDatum(X) ((Datum) SET_1_BYTE(X))
184 * Returns 8-bit unsigned integer value of a datum.
187 #define DatumGetUInt8(X) ((uint8) GET_1_BYTE(X))
191 * Returns datum representation for an 8-bit unsigned integer.
194 #define UInt8GetDatum(X) ((Datum) SET_1_BYTE(X))
198 * Returns 16-bit integer value of a datum.
201 #define DatumGetInt16(X) ((int16) GET_2_BYTES(X))
205 * Returns datum representation for a 16-bit integer.
208 #define Int16GetDatum(X) ((Datum) SET_2_BYTES(X))
212 * Returns 16-bit unsigned integer value of a datum.
215 #define DatumGetUInt16(X) ((uint16) GET_2_BYTES(X))
219 * Returns datum representation for a 16-bit unsigned integer.
222 #define UInt16GetDatum(X) ((Datum) SET_2_BYTES(X))
226 * Returns 32-bit integer value of a datum.
229 #define DatumGetInt32(X) ((int32) GET_4_BYTES(X))
233 * Returns datum representation for a 32-bit integer.
236 #define Int32GetDatum(X) ((Datum) SET_4_BYTES(X))
240 * Returns 32-bit unsigned integer value of a datum.
243 #define DatumGetUInt32(X) ((uint32) GET_4_BYTES(X))
247 * Returns datum representation for a 32-bit unsigned integer.
250 #define UInt32GetDatum(X) ((Datum) SET_4_BYTES(X))
254 * Returns object identifier value of a datum.
257 #define DatumGetObjectId(X) ((Oid) GET_4_BYTES(X))
261 * Returns datum representation for an object identifier.
264 #define ObjectIdGetDatum(X) ((Datum) SET_4_BYTES(X))
267 * DatumGetTransactionId
268 * Returns transaction identifier value of a datum.
271 #define DatumGetTransactionId(X) ((TransactionId) GET_4_BYTES(X))
274 * TransactionIdGetDatum
275 * Returns datum representation for a transaction identifier.
278 #define TransactionIdGetDatum(X) ((Datum) SET_4_BYTES((X)))
282 * Returns command identifier value of a datum.
285 #define DatumGetCommandId(X) ((CommandId) GET_4_BYTES(X))
289 * Returns datum representation for a command identifier.
292 #define CommandIdGetDatum(X) ((Datum) SET_4_BYTES(X))
296 * Returns pointer value of a datum.
299 #define DatumGetPointer(X) ((Pointer) (X))
303 * Returns datum representation for a pointer.
306 #define PointerGetDatum(X) ((Datum) (X))
310 * Returns C string (null-terminated string) value of a datum.
312 * Note: C string is not a full-fledged Postgres type at present,
313 * but type input functions use this conversion for their inputs.
316 #define DatumGetCString(X) ((char *) DatumGetPointer(X))
320 * Returns datum representation for a C string (null-terminated string).
322 * Note: C string is not a full-fledged Postgres type at present,
323 * but type output functions use this conversion for their outputs.
324 * Note: CString is pass-by-reference; caller must ensure the pointed-to
325 * value has adequate lifetime.
328 #define CStringGetDatum(X) PointerGetDatum(X)
332 * Returns name value of a datum.
335 #define DatumGetName(X) ((Name) DatumGetPointer(X))
339 * Returns datum representation for a name.
341 * Note: Name is pass-by-reference; caller must ensure the pointed-to
342 * value has adequate lifetime.
345 #define NameGetDatum(X) PointerGetDatum(X)
349 * Returns 64-bit integer value of a datum.
351 * Note: this macro hides the fact that int64 is currently a
352 * pass-by-reference type. Someday it may be pass-by-value,
353 * at least on some platforms.
356 #define DatumGetInt64(X) (* ((int64 *) DatumGetPointer(X)))
360 * Returns datum representation for a 64-bit integer.
362 * Note: this routine returns a reference to palloc'd space.
365 extern Datum Int64GetDatum(int64 X);
369 * Returns 4-byte floating point value of a datum.
371 * Note: this macro hides the fact that float4 is currently a
372 * pass-by-reference type. Someday it may be pass-by-value.
375 #define DatumGetFloat4(X) (* ((float4 *) DatumGetPointer(X)))
379 * Returns datum representation for a 4-byte floating point number.
381 * Note: this routine returns a reference to palloc'd space.
384 extern Datum Float4GetDatum(float4 X);
388 * Returns 8-byte floating point value of a datum.
390 * Note: this macro hides the fact that float8 is currently a
391 * pass-by-reference type. Someday it may be pass-by-value,
392 * at least on some platforms.
395 #define DatumGetFloat8(X) (* ((float8 *) DatumGetPointer(X)))
399 * Returns datum representation for an 8-byte floating point number.
401 * Note: this routine returns a reference to palloc'd space.
404 extern Datum Float8GetDatum(float8 X);
409 * Returns 32-bit floating point value of a datum.
410 * This is really a pointer, of course.
412 * XXX: this macro is now deprecated in favor of DatumGetFloat4.
413 * It will eventually go away.
416 #define DatumGetFloat32(X) ((float32) DatumGetPointer(X))
420 * Returns datum representation for a 32-bit floating point number.
421 * This is really a pointer, of course.
423 * XXX: this macro is now deprecated in favor of Float4GetDatum.
424 * It will eventually go away.
427 #define Float32GetDatum(X) PointerGetDatum(X)
431 * Returns 64-bit floating point value of a datum.
432 * This is really a pointer, of course.
434 * XXX: this macro is now deprecated in favor of DatumGetFloat8.
435 * It will eventually go away.
438 #define DatumGetFloat64(X) ((float64) DatumGetPointer(X))
442 * Returns datum representation for a 64-bit floating point number.
443 * This is really a pointer, of course.
445 * XXX: this macro is now deprecated in favor of Float8GetDatum.
446 * It will eventually go away.
449 #define Float64GetDatum(X) PointerGetDatum(X)
456 * These macros are intended to allow writing code that does not depend on
457 * whether int64, float4, float8 are pass-by-reference types, while not
458 * sacrificing performance when they are. The argument must be a variable
459 * that will exist and have the same value for as long as the Datum is needed.
460 * In the pass-by-ref case, the address of the variable is taken to use as
461 * the Datum. In the pass-by-val case, these will be the same as the non-Fast
465 #define Int64GetDatumFast(X) PointerGetDatum(&(X))
466 #define Float4GetDatumFast(X) PointerGetDatum(&(X))
467 #define Float8GetDatumFast(X) PointerGetDatum(&(X))
470 /* ----------------------------------------------------------------
471 * Section 3: exception handling definitions
472 * Assert, Trap, etc macros
473 * ----------------------------------------------------------------
476 extern DLLIMPORT bool assert_enabled;
479 * USE_ASSERT_CHECKING, if defined, turns on all the assertions.
482 * It should _NOT_ be defined in releases or in benchmark copies
487 * Generates an exception if the given condition is true.
490 #define Trap(condition, errorType) \
492 if ((assert_enabled) && (condition)) \
493 ExceptionalCondition(CppAsString(condition), (errorType), \
494 __FILE__, __LINE__); \
498 * TrapMacro is the same as Trap but it's intended for use in macros:
500 * #define foo(x) (AssertMacro(x != 0) && bar(x))
504 #define TrapMacro(condition, errorType) \
505 ((bool) ((! assert_enabled) || ! (condition) || \
506 (ExceptionalCondition(CppAsString(condition), (errorType), \
507 __FILE__, __LINE__))))
509 #ifndef USE_ASSERT_CHECKING
510 #define Assert(condition)
511 #define AssertMacro(condition) ((void)true)
512 #define AssertArg(condition)
513 #define AssertState(condition)
514 #define assert_enabled 0
516 #define Assert(condition) \
517 Trap(!(condition), "FailedAssertion")
519 #define AssertMacro(condition) \
520 ((void) TrapMacro(!(condition), "FailedAssertion"))
522 #define AssertArg(condition) \
523 Trap(!(condition), "BadArgument")
525 #define AssertState(condition) \
526 Trap(!(condition), "BadState")
527 #endif /* USE_ASSERT_CHECKING */
529 extern int ExceptionalCondition(char *conditionName, char *errorType,
530 char *fileName, int lineNumber);
532 /* ----------------------------------------------------------------
533 * Section 4: genbki macros used by catalog/pg_xxx.h files
534 * ----------------------------------------------------------------
536 #define CATALOG(x) typedef struct CppConcat(FormData_,x)
539 #define BKI_SHARED_RELATION
540 #define BKI_WITHOUT_OIDS
542 /* these need to expand into some harmless, repeatable declaration */
543 #define DATA(x) extern int no_such_variable
544 #define DESCR(x) extern int no_such_variable
549 typedef int4 aclitem; /* PHONY definition for catalog use only */
551 #endif /* POSTGRES_H */