* Client-side code should include postgres_fe.h instead.
*
*
- * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1995, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/postgres.h,v 1.87 2007/11/15 22:25:16 momjian Exp $
+ * src/include/postgres.h
*
*-------------------------------------------------------------------------
*/
* ------- ------------------------------------------------
* 1) variable-length datatypes (TOAST support)
* 2) datum type + support macros
- * 3) exception handling definitions
- * 4) genbki macros used by catalog/pg_xxx.h files
+ * 3) exception handling backend support
*
* NOTES
*
* 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
+ * 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
*/
/*
- * 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.
+ * struct varatt_external is a traditional "TOAST pointer", that is, the
+ * information needed to fetch a Datum stored out-of-line in a TOAST table.
+ * The data is compressed if and only if va_extsize < va_rawsize - VARHDRSZ.
+ * This struct must not contain any padding, because we sometimes compare
+ * these 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
+typedef 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 */
-};
+} varatt_external;
+
+/*
+ * struct varatt_indirect is a "TOAST pointer" representing an out-of-line
+ * Datum that's stored in memory, not in an external toast relation.
+ * The creator of such a Datum is entirely responsible that the referenced
+ * storage survives for as long as referencing pointer Datums can exist.
+ *
+ * Note that just as for struct varatt_external, this struct is stored
+ * unaligned within any containing tuple.
+ */
+typedef struct varatt_indirect
+{
+ struct varlena *pointer; /* Pointer to in-memory varlena */
+} varatt_indirect;
+
+/*
+ * Type tag for the various sorts of "TOAST pointer" datums. The peculiar
+ * value for VARTAG_ONDISK comes from a requirement for on-disk compatibility
+ * with a previous notion that the tag field was the pointer datum's length.
+ */
+typedef enum vartag_external
+{
+ VARTAG_INDIRECT = 1,
+ VARTAG_ONDISK = 18
+} vartag_external;
+
+#define VARTAG_SIZE(tag) \
+ ((tag) == VARTAG_INDIRECT ? sizeof(varatt_indirect) : \
+ (tag) == VARTAG_ONDISK ? sizeof(varatt_external) : \
+ TrapMacro(true, "unrecognized TOAST vartag"))
/*
* These structs describe the header of a varlena object that may have been
struct /* Normal varlena (4-byte length) */
{
uint32 va_header;
- char va_data[1];
+ char va_data[FLEXIBLE_ARRAY_MEMBER];
} va_4byte;
struct /* Compressed-in-line format */
{
uint32 va_header;
uint32 va_rawsize; /* Original data size (excludes header) */
- char va_data[1]; /* Compressed data */
+ char va_data[FLEXIBLE_ARRAY_MEMBER]; /* Compressed data */
} va_compressed;
} varattrib_4b;
typedef struct
{
uint8 va_header;
- char va_data[1]; /* Data begins here */
+ char va_data[FLEXIBLE_ARRAY_MEMBER]; /* Data begins here */
} varattrib_1b;
+/* TOAST pointers are a subset of varattrib_1b with an identifying tag byte */
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) */
+ uint8 va_tag; /* Type of datum */
+ char va_data[FLEXIBLE_ARRAY_MEMBER]; /* Type-specific data */
} varattrib_1b_e;
/*
* 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;
+ * 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!)
+ *
+ * In TOAST pointers the va_tag field (see varattrib_1b_e) is used to discern
+ * the specific type and length of the pointer datum.
*/
/*
(((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 VARTAG_1B_E(PTR) \
+ (((varattrib_1b_e *) (PTR))->va_tag)
#define SET_VARSIZE_4B(PTR,len) \
(((varattrib_4b *) (PTR))->va_4byte.va_header = (len) & 0x3FFFFFFF)
(((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) \
+#define SET_VARTAG_1B_E(PTR,tag) \
(((varattrib_1b_e *) (PTR))->va_header = 0x80, \
- ((varattrib_1b_e *) (PTR))->va_len_1be = (len))
+ ((varattrib_1b_e *) (PTR))->va_tag = (tag))
#else /* !WORDS_BIGENDIAN */
#define VARATT_IS_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 VARTAG_1B_E(PTR) \
+ (((varattrib_1b_e *) (PTR))->va_tag)
#define SET_VARSIZE_4B(PTR,len) \
(((varattrib_4b *) (PTR))->va_4byte.va_header = (((uint32) (len)) << 2))
(((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) \
+#define SET_VARTAG_1B_E(PTR,tag) \
(((varattrib_1b_e *) (PTR))->va_header = 0x01, \
- ((varattrib_1b_e *) (PTR))->va_len_1be = (len))
+ ((varattrib_1b_e *) (PTR))->va_tag = (tag))
#endif /* WORDS_BIGENDIAN */
-#define VARHDRSZ_SHORT 1
+#define VARHDRSZ_SHORT offsetof(varattrib_1b, va_data)
#define VARATT_SHORT_MAX 0x7F
#define VARATT_CAN_MAKE_SHORT(PTR) \
(VARATT_IS_4B_U(PTR) && \
#define VARATT_CONVERTED_SHORT_SIZE(PTR) \
(VARSIZE(PTR) - VARHDRSZ + VARHDRSZ_SHORT)
-#define VARHDRSZ_EXTERNAL 2
+#define VARHDRSZ_EXTERNAL offsetof(varattrib_1b_e, va_data)
#define VARDATA_4B(PTR) (((varattrib_4b *) (PTR))->va_4byte.va_data)
#define VARDATA_4B_C(PTR) (((varattrib_4b *) (PTR))->va_compressed.va_data)
#define VARSIZE_SHORT(PTR) VARSIZE_1B(PTR)
#define VARDATA_SHORT(PTR) VARDATA_1B(PTR)
-#define VARSIZE_EXTERNAL(PTR) VARSIZE_1B_E(PTR)
+#define VARTAG_EXTERNAL(PTR) VARTAG_1B_E(PTR)
+#define VARSIZE_EXTERNAL(PTR) (VARHDRSZ_EXTERNAL + VARTAG_SIZE(VARTAG_EXTERNAL(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_EXTERNAL_ONDISK(PTR) \
+ (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_ONDISK)
+#define VARATT_IS_EXTERNAL_INDIRECT(PTR) \
+ (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_INDIRECT)
#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 SET_VARTAG_EXTERNAL(PTR, tag) SET_VARTAG_1B_E(PTR, tag)
#define VARSIZE_ANY(PTR) \
- (VARATT_IS_1B_E(PTR) ? VARSIZE_1B_E(PTR) : \
+ (VARATT_IS_1B_E(PTR) ? VARSIZE_EXTERNAL(PTR) : \
(VARATT_IS_1B(PTR) ? VARSIZE_1B(PTR) : \
VARSIZE_4B(PTR)))
+/* Size of a varlena data, excluding header */
#define VARSIZE_ANY_EXHDR(PTR) \
- (VARATT_IS_1B_E(PTR) ? VARSIZE_1B_E(PTR)-VARHDRSZ_EXTERNAL : \
+ (VARATT_IS_1B_E(PTR) ? VARSIZE_EXTERNAL(PTR)-VARHDRSZ_EXTERNAL : \
(VARATT_IS_1B(PTR) ? VARSIZE_1B(PTR)-VARHDRSZ_SHORT : \
VARSIZE_4B(PTR)-VARHDRSZ))
/*
* Port Notes:
- * Postgres makes the following assumption about machines:
- *
- * sizeof(Datum) == sizeof(long) >= sizeof(void *) >= 4
- *
- * Postgres also assumes that
+ * Postgres makes the following assumptions about datatype sizes:
*
+ * sizeof(Datum) == sizeof(void *) == 4 or 8
* sizeof(char) == 1
- *
- * and that
- *
* sizeof(short) == 2
*
* When a type narrower than Datum is stored in a Datum, we place it in the
* or short may contain garbage when called as if it returned Datum.
*/
-typedef unsigned long Datum; /* XXX sizeof(long) >= sizeof(void *) */
+typedef uintptr_t Datum;
-#define SIZEOF_DATUM SIZEOF_UNSIGNED_LONG
+#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
#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.
* DatumGetInt64
* Returns 64-bit integer value of a datum.
*
- * Note: this macro hides the fact that int64 is currently a
- * pass-by-reference type. Someday it may be pass-by-value,
- * at least on some platforms.
+ * 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: this routine returns a reference to palloc'd space.
+ * 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 the fact that float4 is currently a
- * pass-by-reference type. Someday it may be pass-by-value.
+ * 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: this routine returns a reference to palloc'd space.
+ * 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 the fact that float8 is currently a
- * pass-by-reference type. Someday it may be pass-by-value,
- * at least on some platforms.
+ * 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: this routine returns a reference to palloc'd space.
+ * Note: if float8 is pass by reference, this function returns a reference
+ * to palloc'd space.
*/
extern Datum Float8GetDatum(float8 X);
-/*
- * DatumGetFloat32
- * Returns 32-bit floating point value of a datum.
- * This is really a pointer, of course.
- *
- * XXX: this macro is now deprecated in favor of DatumGetFloat4.
- * It will eventually go away.
- */
-
-#define DatumGetFloat32(X) ((float32) DatumGetPointer(X))
-
-/*
- * Float32GetDatum
- * Returns datum representation for a 32-bit floating point number.
- * This is really a pointer, of course.
- *
- * XXX: this macro is now deprecated in favor of Float4GetDatum.
- * It will eventually go away.
- */
-
-#define Float32GetDatum(X) PointerGetDatum(X)
-
-/*
- * DatumGetFloat64
- * Returns 64-bit floating point value of a datum.
- * This is really a pointer, of course.
- *
- * XXX: this macro is now deprecated in favor of DatumGetFloat8.
- * It will eventually go away.
- */
-
-#define DatumGetFloat64(X) ((float64) DatumGetPointer(X))
-
-/*
- * Float64GetDatum
- * Returns datum representation for a 64-bit floating point number.
- * This is really a pointer, of course.
- *
- * XXX: this macro is now deprecated in favor of Float8GetDatum.
- * It will eventually go away.
- */
-
-#define Float64GetDatum(X) PointerGetDatum(X)
-
/*
* Int64GetDatumFast
- * Float4GetDatumFast
* Float8GetDatumFast
+ * Float4GetDatumFast
*
* These macros are intended to allow writing code that does not depend on
- * whether int64, float4, float8 are pass-by-reference types, while not
+ * 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
* macros.
*/
+#ifdef USE_FLOAT8_BYVAL
+#define Int64GetDatumFast(X) Int64GetDatum(X)
+#define Float8GetDatumFast(X) Float8GetDatum(X)
+#else
#define Int64GetDatumFast(X) PointerGetDatum(&(X))
-#define Float4GetDatumFast(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
+ * Section 3: exception handling backend support
* ----------------------------------------------------------------
*/
-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))
+ * Backend only infrastructure for the assertion-related macros in c.h.
*
- * Isn't CPP fun?
+ * ExceptionalCondition must be present even when assertions are not enabled.
*/
-#define TrapMacro(condition, errorType) \
- ((bool) ((! assert_enabled) || ! (condition) || \
- (ExceptionalCondition(CppAsString(condition), (errorType), \
- __FILE__, __LINE__))))
-
-#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 int ExceptionalCondition(const char *conditionName,
+extern void ExceptionalCondition(const char *conditionName,
const char *errorType,
- const char *fileName, int lineNumber);
-
-/* ----------------------------------------------------------------
- * Section 4: genbki macros used by catalog/pg_xxx.h files
- * ----------------------------------------------------------------
- */
-#define CATALOG(name,oid) typedef struct CppConcat(FormData_,name)
-
-#define BKI_BOOTSTRAP
-#define BKI_SHARED_RELATION
-#define BKI_WITHOUT_OIDS
-
-/* these need to expand into some harmless, repeatable declaration */
-#define DATA(x) extern int no_such_variable
-#define DESCR(x) extern int no_such_variable
-#define SHDESCR(x) extern int no_such_variable
-
-typedef int4 aclitem; /* PHONY definition for catalog use only */
+ const char *fileName, int lineNumber) pg_attribute_noreturn;
#endif /* POSTGRES_H */