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) 1996-2007, PostgreSQL Global Development Group
11 * Portions Copyright (c) 1995, Regents of the University of California
13 * $PostgreSQL: pgsql/src/include/postgres.h,v 1.77 2007/02/27 23:48:09 tgl 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
59 * TOASTed. Generally, only the code closely associated with TOAST logic
60 * should mess directly with struct varattrib or use the VARATT_FOO macros.
63 typedef struct varattrib
65 int32 va_header_; /* External/compressed storage */
66 /* flags and item size */
71 int32 va_rawsize; /* Plain data size */
72 char va_data[1]; /* Compressed data */
73 } va_compressed; /* Compressed stored attribute */
77 int32 va_rawsize; /* Plain data size */
78 int32 va_extsize; /* External saved size */
79 Oid va_valueid; /* Unique identifier of value */
80 Oid va_toastrelid; /* RelID where to find chunks */
81 } va_external; /* External stored attribute */
83 char va_data[1]; /* Plain stored attribute */
87 #define VARATT_FLAG_EXTERNAL 0x80000000
88 #define VARATT_FLAG_COMPRESSED 0x40000000
89 #define VARATT_MASK_FLAGS 0xc0000000
90 #define VARATT_MASK_SIZE 0x3fffffff
92 #define VARATT_SIZEP_DEPRECATED(PTR) (((varattrib *) (PTR))->va_header_)
94 #define VARATT_IS_EXTENDED(PTR) \
95 ((VARATT_SIZEP_DEPRECATED(PTR) & VARATT_MASK_FLAGS) != 0)
96 #define VARATT_IS_EXTERNAL(PTR) \
97 ((VARATT_SIZEP_DEPRECATED(PTR) & VARATT_FLAG_EXTERNAL) != 0)
98 #define VARATT_IS_COMPRESSED(PTR) \
99 ((VARATT_SIZEP_DEPRECATED(PTR) & VARATT_FLAG_COMPRESSED) != 0)
101 /* These macros are the ones for non-TOAST code to use */
103 #define VARSIZE(PTR) (VARATT_SIZEP_DEPRECATED(PTR) & VARATT_MASK_SIZE)
104 #define VARDATA(PTR) (((varattrib *) (PTR))->va_content.va_data)
106 #define SET_VARSIZE(PTR,SIZE) (VARATT_SIZEP_DEPRECATED(PTR) = (SIZE))
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 *) */
134 #define SIZEOF_DATUM SIZEOF_UNSIGNED_LONG
135 typedef Datum *DatumPtr;
137 #define GET_1_BYTE(datum) (((Datum) (datum)) & 0x000000ff)
138 #define GET_2_BYTES(datum) (((Datum) (datum)) & 0x0000ffff)
139 #define GET_4_BYTES(datum) (((Datum) (datum)) & 0xffffffff)
140 #define SET_1_BYTE(value) (((Datum) (value)) & 0x000000ff)
141 #define SET_2_BYTES(value) (((Datum) (value)) & 0x0000ffff)
142 #define SET_4_BYTES(value) (((Datum) (value)) & 0xffffffff)
146 * Returns boolean value of a datum.
148 * Note: any nonzero value will be considered TRUE.
151 #define DatumGetBool(X) ((bool) (((Datum) (X)) != 0))
155 * Returns datum representation for a boolean.
157 * Note: any nonzero value will be considered TRUE.
160 #define BoolGetDatum(X) ((Datum) ((X) ? 1 : 0))
164 * Returns character value of a datum.
167 #define DatumGetChar(X) ((char) GET_1_BYTE(X))
171 * Returns datum representation for a character.
174 #define CharGetDatum(X) ((Datum) SET_1_BYTE(X))
178 * Returns datum representation for an 8-bit integer.
181 #define Int8GetDatum(X) ((Datum) SET_1_BYTE(X))
185 * Returns 8-bit unsigned integer value of a datum.
188 #define DatumGetUInt8(X) ((uint8) GET_1_BYTE(X))
192 * Returns datum representation for an 8-bit unsigned integer.
195 #define UInt8GetDatum(X) ((Datum) SET_1_BYTE(X))
199 * Returns 16-bit integer value of a datum.
202 #define DatumGetInt16(X) ((int16) GET_2_BYTES(X))
206 * Returns datum representation for a 16-bit integer.
209 #define Int16GetDatum(X) ((Datum) SET_2_BYTES(X))
213 * Returns 16-bit unsigned integer value of a datum.
216 #define DatumGetUInt16(X) ((uint16) GET_2_BYTES(X))
220 * Returns datum representation for a 16-bit unsigned integer.
223 #define UInt16GetDatum(X) ((Datum) SET_2_BYTES(X))
227 * Returns 32-bit integer value of a datum.
230 #define DatumGetInt32(X) ((int32) GET_4_BYTES(X))
234 * Returns datum representation for a 32-bit integer.
237 #define Int32GetDatum(X) ((Datum) SET_4_BYTES(X))
241 * Returns 32-bit unsigned integer value of a datum.
244 #define DatumGetUInt32(X) ((uint32) GET_4_BYTES(X))
248 * Returns datum representation for a 32-bit unsigned integer.
251 #define UInt32GetDatum(X) ((Datum) SET_4_BYTES(X))
255 * Returns object identifier value of a datum.
258 #define DatumGetObjectId(X) ((Oid) GET_4_BYTES(X))
262 * Returns datum representation for an object identifier.
265 #define ObjectIdGetDatum(X) ((Datum) SET_4_BYTES(X))
268 * DatumGetTransactionId
269 * Returns transaction identifier value of a datum.
272 #define DatumGetTransactionId(X) ((TransactionId) GET_4_BYTES(X))
275 * TransactionIdGetDatum
276 * Returns datum representation for a transaction identifier.
279 #define TransactionIdGetDatum(X) ((Datum) SET_4_BYTES((X)))
283 * Returns command identifier value of a datum.
286 #define DatumGetCommandId(X) ((CommandId) GET_4_BYTES(X))
290 * Returns datum representation for a command identifier.
293 #define CommandIdGetDatum(X) ((Datum) SET_4_BYTES(X))
297 * Returns pointer value of a datum.
300 #define DatumGetPointer(X) ((Pointer) (X))
304 * Returns datum representation for a pointer.
307 #define PointerGetDatum(X) ((Datum) (X))
311 * Returns C string (null-terminated string) value of a datum.
313 * Note: C string is not a full-fledged Postgres type at present,
314 * but type input functions use this conversion for their inputs.
317 #define DatumGetCString(X) ((char *) DatumGetPointer(X))
321 * Returns datum representation for a C string (null-terminated string).
323 * Note: C string is not a full-fledged Postgres type at present,
324 * but type output functions use this conversion for their outputs.
325 * Note: CString is pass-by-reference; caller must ensure the pointed-to
326 * value has adequate lifetime.
329 #define CStringGetDatum(X) PointerGetDatum(X)
333 * Returns name value of a datum.
336 #define DatumGetName(X) ((Name) DatumGetPointer(X))
340 * Returns datum representation for a name.
342 * Note: Name is pass-by-reference; caller must ensure the pointed-to
343 * value has adequate lifetime.
346 #define NameGetDatum(X) PointerGetDatum(X)
350 * Returns 64-bit integer value of a datum.
352 * Note: this macro hides the fact that int64 is currently a
353 * pass-by-reference type. Someday it may be pass-by-value,
354 * at least on some platforms.
357 #define DatumGetInt64(X) (* ((int64 *) DatumGetPointer(X)))
361 * Returns datum representation for a 64-bit integer.
363 * Note: this routine returns a reference to palloc'd space.
366 extern Datum Int64GetDatum(int64 X);
370 * Returns 4-byte floating point value of a datum.
372 * Note: this macro hides the fact that float4 is currently a
373 * pass-by-reference type. Someday it may be pass-by-value.
376 #define DatumGetFloat4(X) (* ((float4 *) DatumGetPointer(X)))
380 * Returns datum representation for a 4-byte floating point number.
382 * Note: this routine returns a reference to palloc'd space.
385 extern Datum Float4GetDatum(float4 X);
389 * Returns 8-byte floating point value of a datum.
391 * Note: this macro hides the fact that float8 is currently a
392 * pass-by-reference type. Someday it may be pass-by-value,
393 * at least on some platforms.
396 #define DatumGetFloat8(X) (* ((float8 *) DatumGetPointer(X)))
400 * Returns datum representation for an 8-byte floating point number.
402 * Note: this routine returns a reference to palloc'd space.
405 extern Datum Float8GetDatum(float8 X);
410 * Returns 32-bit floating point value of a datum.
411 * This is really a pointer, of course.
413 * XXX: this macro is now deprecated in favor of DatumGetFloat4.
414 * It will eventually go away.
417 #define DatumGetFloat32(X) ((float32) DatumGetPointer(X))
421 * Returns datum representation for a 32-bit floating point number.
422 * This is really a pointer, of course.
424 * XXX: this macro is now deprecated in favor of Float4GetDatum.
425 * It will eventually go away.
428 #define Float32GetDatum(X) PointerGetDatum(X)
432 * Returns 64-bit floating point value of a datum.
433 * This is really a pointer, of course.
435 * XXX: this macro is now deprecated in favor of DatumGetFloat8.
436 * It will eventually go away.
439 #define DatumGetFloat64(X) ((float64) DatumGetPointer(X))
443 * Returns datum representation for a 64-bit floating point number.
444 * This is really a pointer, of course.
446 * XXX: this macro is now deprecated in favor of Float8GetDatum.
447 * It will eventually go away.
450 #define Float64GetDatum(X) PointerGetDatum(X)
457 * These macros are intended to allow writing code that does not depend on
458 * whether int64, float4, float8 are pass-by-reference types, while not
459 * sacrificing performance when they are. The argument must be a variable
460 * that will exist and have the same value for as long as the Datum is needed.
461 * In the pass-by-ref case, the address of the variable is taken to use as
462 * the Datum. In the pass-by-val case, these will be the same as the non-Fast
466 #define Int64GetDatumFast(X) PointerGetDatum(&(X))
467 #define Float4GetDatumFast(X) PointerGetDatum(&(X))
468 #define Float8GetDatumFast(X) PointerGetDatum(&(X))
471 /* ----------------------------------------------------------------
472 * Section 3: exception handling definitions
473 * Assert, Trap, etc macros
474 * ----------------------------------------------------------------
477 extern DLLIMPORT bool assert_enabled;
480 * USE_ASSERT_CHECKING, if defined, turns on all the assertions.
483 * It should _NOT_ be defined in releases or in benchmark copies
488 * 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)
515 #define Assert(condition) \
516 Trap(!(condition), "FailedAssertion")
518 #define AssertMacro(condition) \
519 ((void) TrapMacro(!(condition), "FailedAssertion"))
521 #define AssertArg(condition) \
522 Trap(!(condition), "BadArgument")
524 #define AssertState(condition) \
525 Trap(!(condition), "BadState")
526 #endif /* USE_ASSERT_CHECKING */
528 extern int ExceptionalCondition(char *conditionName, char *errorType,
529 char *fileName, int lineNumber);
531 /* ----------------------------------------------------------------
532 * Section 4: genbki macros used by catalog/pg_xxx.h files
533 * ----------------------------------------------------------------
535 #define CATALOG(name,oid) typedef struct CppConcat(FormData_,name)
537 #define BKI_BOOTSTRAP
538 #define BKI_SHARED_RELATION
539 #define BKI_WITHOUT_OIDS
541 /* these need to expand into some harmless, repeatable declaration */
542 #define DATA(x) extern int no_such_variable
543 #define DESCR(x) extern int no_such_variable
544 #define SHDESCR(x) extern int no_such_variable
546 typedef int4 aclitem; /* PHONY definition for catalog use only */
548 #endif /* POSTGRES_H */