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- /*-------------------------------------------------------------------------
- *
- * c.h
- * Fundamental C definitions. This is included by every .c file in
- * PostgreSQL (via either postgres.h or postgres_fe.h, as appropriate).
- *
- * Note that the definitions here are not intended to be exposed to clients
- * of the frontend interface libraries --- so we don't worry much about
- * polluting the namespace with lots of stuff...
- *
- *
- * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- * src/include/c.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
- * ------- ------------------------------------------------
- * 0) pg_config.h and standard system headers
- * 1) compiler characteristics
- * 2) bool, true, false
- * 3) standard system types
- * 4) IsValid macros for system types
- * 5) offsetof, lengthof, alignment
- * 6) assertions
- * 7) widely useful macros
- * 8) random stuff
- * 9) system-specific hacks
- *
- * NOTE: since this file is included by both frontend and backend modules,
- * it's usually wrong to put an "extern" declaration here, unless it's
- * ifdef'd so that it's seen in only one case or the other.
- * typedefs and macros are the kind of thing that might go here.
- *
- *----------------------------------------------------------------
- */
- #ifndef C_H
- #define C_H
-
- #include "postgres_ext.h"
-
- /* Must undef pg_config_ext.h symbols before including pg_config.h */
- #undef PG_INT64_TYPE
-
- #include "pg_config.h"
- #include "pg_config_manual.h" /* must be after pg_config.h */
- #include "pg_config_os.h" /* must be before any system header files */
-
- /* System header files that should be available everywhere in Postgres */
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <stddef.h>
- #include <stdarg.h>
- #ifdef HAVE_STRINGS_H
- #include <strings.h>
- #endif
- #ifdef HAVE_STDINT_H
- #include <stdint.h>
- #endif
- #include <sys/types.h>
- #include <errno.h>
- #if defined(WIN32) || defined(__CYGWIN__)
- #include <fcntl.h> /* ensure O_BINARY is available */
- #endif
- #include <locale.h>
- #ifdef ENABLE_NLS
- #include <libintl.h>
- #endif
-
-
- /* ----------------------------------------------------------------
- * Section 1: compiler characteristics
- *
- * type prefixes (const, signed, volatile, inline) are handled in pg_config.h.
- * ----------------------------------------------------------------
- */
-
- /*
- * Disable "inline" if PG_FORCE_DISABLE_INLINE is defined.
- * This is used to work around compiler bugs and might also be useful for
- * investigatory purposes.
- */
- #ifdef PG_FORCE_DISABLE_INLINE
- #undef inline
- #define inline
- #endif
-
- /*
- * Attribute macros
- *
- * GCC: https://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
- * GCC: https://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html
- * Sunpro: https://docs.oracle.com/cd/E18659_01/html/821-1384/gjzke.html
- * XLC: http://www-01.ibm.com/support/knowledgecenter/SSGH2K_11.1.0/com.ibm.xlc111.aix.doc/language_ref/function_attributes.html
- * XLC: http://www-01.ibm.com/support/knowledgecenter/SSGH2K_11.1.0/com.ibm.xlc111.aix.doc/language_ref/type_attrib.html
- */
-
- /* only GCC supports the unused attribute */
- #ifdef __GNUC__
- #define pg_attribute_unused() __attribute__((unused))
- #else
- #define pg_attribute_unused()
- #endif
-
- /*
- * Append PG_USED_FOR_ASSERTS_ONLY to definitions of variables that are only
- * used in assert-enabled builds, to avoid compiler warnings about unused
- * variables in assert-disabled builds.
- */
- #ifdef USE_ASSERT_CHECKING
- #define PG_USED_FOR_ASSERTS_ONLY
- #else
- #define PG_USED_FOR_ASSERTS_ONLY pg_attribute_unused()
- #endif
-
- /* GCC and XLC support format attributes */
- #if defined(__GNUC__) || defined(__IBMC__)
- #define pg_attribute_format_arg(a) __attribute__((format_arg(a)))
- #define pg_attribute_printf(f,a) __attribute__((format(PG_PRINTF_ATTRIBUTE, f, a)))
- #else
- #define pg_attribute_format_arg(a)
- #define pg_attribute_printf(f,a)
- #endif
-
- /* GCC, Sunpro and XLC support aligned, packed and noreturn */
- #if defined(__GNUC__) || defined(__SUNPRO_C) || defined(__IBMC__)
- #define pg_attribute_aligned(a) __attribute__((aligned(a)))
- #define pg_attribute_noreturn() __attribute__((noreturn))
- #define pg_attribute_packed() __attribute__((packed))
- #define HAVE_PG_ATTRIBUTE_NORETURN 1
- #else
- /*
- * NB: aligned and packed are not given default definitions because they
- * affect code functionality; they *must* be implemented by the compiler
- * if they are to be used.
- */
- #define pg_attribute_noreturn()
- #endif
-
- /*
- * Use "pg_attribute_always_inline" in place of "inline" for functions that
- * we wish to force inlining of, even when the compiler's heuristics would
- * choose not to. But, if possible, don't force inlining in unoptimized
- * debug builds.
- */
- #if (defined(__GNUC__) && __GNUC__ > 3 && defined(__OPTIMIZE__)) || defined(__SUNPRO_C) || defined(__IBMC__)
- /* GCC > 3, Sunpro and XLC support always_inline via __attribute__ */
- #define pg_attribute_always_inline __attribute__((always_inline)) inline
- #elif defined(_MSC_VER)
- /* MSVC has a special keyword for this */
- #define pg_attribute_always_inline __forceinline
- #else
- /* Otherwise, the best we can do is to say "inline" */
- #define pg_attribute_always_inline inline
- #endif
-
- /*
- * Forcing a function not to be inlined can be useful if it's the slow path of
- * a performance-critical function, or should be visible in profiles to allow
- * for proper cost attribution. Note that unlike the pg_attribute_XXX macros
- * above, this should be placed before the function's return type and name.
- */
- /* GCC, Sunpro and XLC support noinline via __attribute__ */
- #if (defined(__GNUC__) && __GNUC__ > 2) || defined(__SUNPRO_C) || defined(__IBMC__)
- #define pg_noinline __attribute__((noinline))
- /* msvc via declspec */
- #elif defined(_MSC_VER)
- #define pg_noinline __declspec(noinline)
- #else
- #define pg_noinline
- #endif
-
- /*
- * Mark a point as unreachable in a portable fashion. This should preferably
- * be something that the compiler understands, to aid code generation.
- * In assert-enabled builds, we prefer abort() for debugging reasons.
- */
- #if defined(HAVE__BUILTIN_UNREACHABLE) && !defined(USE_ASSERT_CHECKING)
- #define pg_unreachable() __builtin_unreachable()
- #elif defined(_MSC_VER) && !defined(USE_ASSERT_CHECKING)
- #define pg_unreachable() __assume(0)
- #else
- #define pg_unreachable() abort()
- #endif
-
- /*
- * Hints to the compiler about the likelihood of a branch. Both likely() and
- * unlikely() return the boolean value of the contained expression.
- *
- * These should only be used sparingly, in very hot code paths. It's very easy
- * to mis-estimate likelihoods.
- */
- #if __GNUC__ >= 3
- #define likely(x) __builtin_expect((x) != 0, 1)
- #define unlikely(x) __builtin_expect((x) != 0, 0)
- #else
- #define likely(x) ((x) != 0)
- #define unlikely(x) ((x) != 0)
- #endif
-
- /*
- * CppAsString
- * Convert the argument to a string, using the C preprocessor.
- * CppAsString2
- * Convert the argument to a string, after one round of macro expansion.
- * CppConcat
- * Concatenate two arguments together, using the C preprocessor.
- *
- * Note: There used to be support here for pre-ANSI C compilers that didn't
- * support # and ##. Nowadays, these macros are just for clarity and/or
- * backward compatibility with existing PostgreSQL code.
- */
- #define CppAsString(identifier) #identifier
- #define CppAsString2(x) CppAsString(x)
- #define CppConcat(x, y) x##y
-
- /*
- * VA_ARGS_NARGS
- * Returns the number of macro arguments it is passed.
- *
- * An empty argument still counts as an argument, so effectively, this is
- * "one more than the number of commas in the argument list".
- *
- * This works for up to 63 arguments. Internally, VA_ARGS_NARGS_() is passed
- * 64+N arguments, and the C99 standard only requires macros to allow up to
- * 127 arguments, so we can't portably go higher. The implementation is
- * pretty trivial: VA_ARGS_NARGS_() returns its 64th argument, and we set up
- * the call so that that is the appropriate one of the list of constants.
- * This idea is due to Laurent Deniau.
- */
- #define VA_ARGS_NARGS(...) \
- VA_ARGS_NARGS_(__VA_ARGS__, \
- 63,62,61,60, \
- 59,58,57,56,55,54,53,52,51,50, \
- 49,48,47,46,45,44,43,42,41,40, \
- 39,38,37,36,35,34,33,32,31,30, \
- 29,28,27,26,25,24,23,22,21,20, \
- 19,18,17,16,15,14,13,12,11,10, \
- 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
- #define VA_ARGS_NARGS_( \
- _01,_02,_03,_04,_05,_06,_07,_08,_09,_10, \
- _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
- _21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
- _31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \
- _41,_42,_43,_44,_45,_46,_47,_48,_49,_50, \
- _51,_52,_53,_54,_55,_56,_57,_58,_59,_60, \
- _61,_62,_63, N, ...) \
- (N)
-
- /*
- * dummyret is used to set return values in macros that use ?: to make
- * assignments. gcc wants these to be void, other compilers like char
- */
- #ifdef __GNUC__ /* GNU cc */
- #define dummyret void
- #else
- #define dummyret char
- #endif
-
- /* Which __func__ symbol do we have, if any? */
- #ifdef HAVE_FUNCNAME__FUNC
- #define PG_FUNCNAME_MACRO __func__
- #else
- #ifdef HAVE_FUNCNAME__FUNCTION
- #define PG_FUNCNAME_MACRO __FUNCTION__
- #else
- #define PG_FUNCNAME_MACRO NULL
- #endif
- #endif
-
-
- /* ----------------------------------------------------------------
- * Section 2: bool, true, false
- * ----------------------------------------------------------------
- */
-
- /*
- * bool
- * Boolean value, either true or false.
- *
- * Use stdbool.h if available and its bool has size 1. That's useful for
- * better compiler and debugger output and for compatibility with third-party
- * libraries. But PostgreSQL currently cannot deal with bool of other sizes;
- * there are static assertions around the code to prevent that.
- *
- * For C++ compilers, we assume the compiler has a compatible built-in
- * definition of bool.
- */
-
- #ifndef __cplusplus
-
- #if defined(HAVE_STDBOOL_H) && SIZEOF_BOOL == 1
- #include <stdbool.h>
- #define USE_STDBOOL 1
- #else
-
- #ifndef bool
- typedef unsigned char bool;
- #endif
-
- #ifndef true
- #define true ((bool) 1)
- #endif
-
- #ifndef false
- #define false ((bool) 0)
- #endif
-
- #endif
- #endif /* not C++ */
-
-
- /* ----------------------------------------------------------------
- * Section 3: standard system types
- * ----------------------------------------------------------------
- */
-
- /*
- * Pointer
- * Variable holding address of any memory resident object.
- *
- * XXX Pointer arithmetic is done with this, so it can't be void *
- * under "true" ANSI compilers.
- */
- typedef char *Pointer;
-
- /*
- * intN
- * Signed integer, EXACTLY N BITS IN SIZE,
- * used for numerical computations and the
- * frontend/backend protocol.
- */
- #ifndef HAVE_INT8
- typedef signed char int8; /* == 8 bits */
- typedef signed short int16; /* == 16 bits */
- typedef signed int int32; /* == 32 bits */
- #endif /* not HAVE_INT8 */
-
- /*
- * uintN
- * Unsigned integer, EXACTLY N BITS IN SIZE,
- * used for numerical computations and the
- * frontend/backend protocol.
- */
- #ifndef HAVE_UINT8
- typedef unsigned char uint8; /* == 8 bits */
- typedef unsigned short uint16; /* == 16 bits */
- typedef unsigned int uint32; /* == 32 bits */
- #endif /* not HAVE_UINT8 */
-
- /*
- * bitsN
- * Unit of bitwise operation, AT LEAST N BITS IN SIZE.
- */
- typedef uint8 bits8; /* >= 8 bits */
- typedef uint16 bits16; /* >= 16 bits */
- typedef uint32 bits32; /* >= 32 bits */
-
- /*
- * 64-bit integers
- */
- #ifdef HAVE_LONG_INT_64
- /* Plain "long int" fits, use it */
-
- #ifndef HAVE_INT64
- typedef long int int64;
- #endif
- #ifndef HAVE_UINT64
- typedef unsigned long int uint64;
- #endif
- #define INT64CONST(x) (x##L)
- #define UINT64CONST(x) (x##UL)
- #elif defined(HAVE_LONG_LONG_INT_64)
- /* We have working support for "long long int", use that */
-
- #ifndef HAVE_INT64
- typedef long long int int64;
- #endif
- #ifndef HAVE_UINT64
- typedef unsigned long long int uint64;
- #endif
- #define INT64CONST(x) (x##LL)
- #define UINT64CONST(x) (x##ULL)
- #else
- /* neither HAVE_LONG_INT_64 nor HAVE_LONG_LONG_INT_64 */
- #error must have a working 64-bit integer datatype
- #endif
-
- /* snprintf format strings to use for 64-bit integers */
- #define INT64_FORMAT "%" INT64_MODIFIER "d"
- #define UINT64_FORMAT "%" INT64_MODIFIER "u"
-
- /*
- * 128-bit signed and unsigned integers
- * There currently is only limited support for such types.
- * E.g. 128bit literals and snprintf are not supported; but math is.
- * Also, because we exclude such types when choosing MAXIMUM_ALIGNOF,
- * it must be possible to coerce the compiler to allocate them on no
- * more than MAXALIGN boundaries.
- */
- #if defined(PG_INT128_TYPE)
- #if defined(pg_attribute_aligned) || ALIGNOF_PG_INT128_TYPE <= MAXIMUM_ALIGNOF
- #define HAVE_INT128 1
-
- typedef PG_INT128_TYPE int128
- #if defined(pg_attribute_aligned)
- pg_attribute_aligned(MAXIMUM_ALIGNOF)
- #endif
- ;
-
- typedef unsigned PG_INT128_TYPE uint128
- #if defined(pg_attribute_aligned)
- pg_attribute_aligned(MAXIMUM_ALIGNOF)
- #endif
- ;
-
- #endif
- #endif
-
- /*
- * stdint.h limits aren't guaranteed to be present and aren't guaranteed to
- * have compatible types with our fixed width types. So just define our own.
- */
- #define PG_INT8_MIN (-0x7F-1)
- #define PG_INT8_MAX (0x7F)
- #define PG_UINT8_MAX (0xFF)
- #define PG_INT16_MIN (-0x7FFF-1)
- #define PG_INT16_MAX (0x7FFF)
- #define PG_UINT16_MAX (0xFFFF)
- #define PG_INT32_MIN (-0x7FFFFFFF-1)
- #define PG_INT32_MAX (0x7FFFFFFF)
- #define PG_UINT32_MAX (0xFFFFFFFFU)
- #define PG_INT64_MIN (-INT64CONST(0x7FFFFFFFFFFFFFFF) - 1)
- #define PG_INT64_MAX INT64CONST(0x7FFFFFFFFFFFFFFF)
- #define PG_UINT64_MAX UINT64CONST(0xFFFFFFFFFFFFFFFF)
-
- /* Max value of size_t might also be missing if we don't have stdint.h */
- #ifndef SIZE_MAX
- #if SIZEOF_SIZE_T == 8
- #define SIZE_MAX PG_UINT64_MAX
- #else
- #define SIZE_MAX PG_UINT32_MAX
- #endif
- #endif
-
- /*
- * We now always use int64 timestamps, but keep this symbol defined for the
- * benefit of external code that might test it.
- */
- #define HAVE_INT64_TIMESTAMP
-
- /*
- * Size
- * Size of any memory resident object, as returned by sizeof.
- */
- typedef size_t Size;
-
- /*
- * Index
- * Index into any memory resident array.
- *
- * Note:
- * Indices are non negative.
- */
- typedef unsigned int Index;
-
- /*
- * Offset
- * Offset into any memory resident array.
- *
- * Note:
- * This differs from an Index in that an Index is always
- * non negative, whereas Offset may be negative.
- */
- typedef signed int Offset;
-
- /*
- * Common Postgres datatype names (as used in the catalogs)
- */
- typedef float float4;
- typedef double float8;
-
- /*
- * Oid, RegProcedure, TransactionId, SubTransactionId, MultiXactId,
- * CommandId
- */
-
- /* typedef Oid is in postgres_ext.h */
-
- /*
- * regproc is the type name used in the include/catalog headers, but
- * RegProcedure is the preferred name in C code.
- */
- typedef Oid regproc;
- typedef regproc RegProcedure;
-
- typedef uint32 TransactionId;
-
- typedef uint32 LocalTransactionId;
-
- typedef uint32 SubTransactionId;
-
- #define InvalidSubTransactionId ((SubTransactionId) 0)
- #define TopSubTransactionId ((SubTransactionId) 1)
-
- /* MultiXactId must be equivalent to TransactionId, to fit in t_xmax */
- typedef TransactionId MultiXactId;
-
- typedef uint32 MultiXactOffset;
-
- typedef uint32 CommandId;
-
- #define FirstCommandId ((CommandId) 0)
- #define InvalidCommandId (~(CommandId)0)
-
- /*
- * Array indexing support
- */
- #define MAXDIM 6
- typedef struct
- {
- int indx[MAXDIM];
- } IntArray;
-
- /* ----------------
- * Variable-length datatypes all share the 'struct varlena' header.
- *
- * NOTE: for TOASTable types, this is an oversimplification, since the value
- * may be compressed or moved out-of-line. However datatype-specific routines
- * are mostly content to deal with de-TOASTed values only, and of course
- * client-side routines should never see a TOASTed value. But even in a
- * de-TOASTed value, beware of touching vl_len_ directly, as its
- * representation is no longer convenient. It's recommended that code always
- * use macros VARDATA_ANY, VARSIZE_ANY, VARSIZE_ANY_EXHDR, VARDATA, VARSIZE,
- * and SET_VARSIZE instead of relying on direct mentions of the struct fields.
- * See postgres.h for details of the TOASTed form.
- * ----------------
- */
- struct varlena
- {
- char vl_len_[4]; /* Do not touch this field directly! */
- char vl_dat[FLEXIBLE_ARRAY_MEMBER]; /* Data content is here */
- };
-
- #define VARHDRSZ ((int32) sizeof(int32))
-
- /*
- * These widely-used datatypes are just a varlena header and the data bytes.
- * There is no terminating null or anything like that --- the data length is
- * always VARSIZE_ANY_EXHDR(ptr).
- */
- typedef struct varlena bytea;
- typedef struct varlena text;
- typedef struct varlena BpChar; /* blank-padded char, ie SQL char(n) */
- typedef struct varlena VarChar; /* var-length char, ie SQL varchar(n) */
-
- /*
- * Specialized array types. These are physically laid out just the same
- * as regular arrays (so that the regular array subscripting code works
- * with them). They exist as distinct types mostly for historical reasons:
- * they have nonstandard I/O behavior which we don't want to change for fear
- * of breaking applications that look at the system catalogs. There is also
- * an implementation issue for oidvector: it's part of the primary key for
- * pg_proc, and we can't use the normal btree array support routines for that
- * without circularity.
- */
- typedef struct
- {
- int32 vl_len_; /* these fields must match ArrayType! */
- int ndim; /* always 1 for int2vector */
- int32 dataoffset; /* always 0 for int2vector */
- Oid elemtype;
- int dim1;
- int lbound1;
- int16 values[FLEXIBLE_ARRAY_MEMBER];
- } int2vector;
-
- typedef struct
- {
- int32 vl_len_; /* these fields must match ArrayType! */
- int ndim; /* always 1 for oidvector */
- int32 dataoffset; /* always 0 for oidvector */
- Oid elemtype;
- int dim1;
- int lbound1;
- Oid values[FLEXIBLE_ARRAY_MEMBER];
- } oidvector;
-
- /*
- * Representation of a Name: effectively just a C string, but null-padded to
- * exactly NAMEDATALEN bytes. The use of a struct is historical.
- */
- typedef struct nameData
- {
- char data[NAMEDATALEN];
- } NameData;
- typedef NameData *Name;
-
- #define NameStr(name) ((name).data)
-
-
- /* ----------------------------------------------------------------
- * Section 4: IsValid macros for system types
- * ----------------------------------------------------------------
- */
- /*
- * BoolIsValid
- * True iff bool is valid.
- */
- #define BoolIsValid(boolean) ((boolean) == false || (boolean) == true)
-
- /*
- * PointerIsValid
- * True iff pointer is valid.
- */
- #define PointerIsValid(pointer) ((const void*)(pointer) != NULL)
-
- /*
- * PointerIsAligned
- * True iff pointer is properly aligned to point to the given type.
- */
- #define PointerIsAligned(pointer, type) \
- (((uintptr_t)(pointer) % (sizeof (type))) == 0)
-
- #define OffsetToPointer(base, offset) \
- ((void *)((char *) base + offset))
-
- #define OidIsValid(objectId) ((bool) ((objectId) != InvalidOid))
-
- #define RegProcedureIsValid(p) OidIsValid(p)
-
-
- /* ----------------------------------------------------------------
- * Section 5: offsetof, lengthof, alignment
- * ----------------------------------------------------------------
- */
- /*
- * offsetof
- * Offset of a structure/union field within that structure/union.
- *
- * XXX This is supposed to be part of stddef.h, but isn't on
- * some systems (like SunOS 4).
- */
- #ifndef offsetof
- #define offsetof(type, field) ((long) &((type *)0)->field)
- #endif /* offsetof */
-
- /*
- * lengthof
- * Number of elements in an array.
- */
- #define lengthof(array) (sizeof (array) / sizeof ((array)[0]))
-
- /* ----------------
- * Alignment macros: align a length or address appropriately for a given type.
- * The fooALIGN() macros round up to a multiple of the required alignment,
- * while the fooALIGN_DOWN() macros round down. The latter are more useful
- * for problems like "how many X-sized structures will fit in a page?".
- *
- * NOTE: TYPEALIGN[_DOWN] will not work if ALIGNVAL is not a power of 2.
- * That case seems extremely unlikely to be needed in practice, however.
- *
- * NOTE: MAXIMUM_ALIGNOF, and hence MAXALIGN(), intentionally exclude any
- * larger-than-8-byte types the compiler might have.
- * ----------------
- */
-
- #define TYPEALIGN(ALIGNVAL,LEN) \
- (((uintptr_t) (LEN) + ((ALIGNVAL) - 1)) & ~((uintptr_t) ((ALIGNVAL) - 1)))
-
- #define SHORTALIGN(LEN) TYPEALIGN(ALIGNOF_SHORT, (LEN))
- #define INTALIGN(LEN) TYPEALIGN(ALIGNOF_INT, (LEN))
- #define LONGALIGN(LEN) TYPEALIGN(ALIGNOF_LONG, (LEN))
- #define DOUBLEALIGN(LEN) TYPEALIGN(ALIGNOF_DOUBLE, (LEN))
- #define MAXALIGN(LEN) TYPEALIGN(MAXIMUM_ALIGNOF, (LEN))
- /* MAXALIGN covers only built-in types, not buffers */
- #define BUFFERALIGN(LEN) TYPEALIGN(ALIGNOF_BUFFER, (LEN))
- #define CACHELINEALIGN(LEN) TYPEALIGN(PG_CACHE_LINE_SIZE, (LEN))
-
- #define TYPEALIGN_DOWN(ALIGNVAL,LEN) \
- (((uintptr_t) (LEN)) & ~((uintptr_t) ((ALIGNVAL) - 1)))
-
- #define SHORTALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_SHORT, (LEN))
- #define INTALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_INT, (LEN))
- #define LONGALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_LONG, (LEN))
- #define DOUBLEALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_DOUBLE, (LEN))
- #define MAXALIGN_DOWN(LEN) TYPEALIGN_DOWN(MAXIMUM_ALIGNOF, (LEN))
- #define BUFFERALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_BUFFER, (LEN))
-
- /*
- * The above macros will not work with types wider than uintptr_t, like with
- * uint64 on 32-bit platforms. That's not problem for the usual use where a
- * pointer or a length is aligned, but for the odd case that you need to
- * align something (potentially) wider, use TYPEALIGN64.
- */
- #define TYPEALIGN64(ALIGNVAL,LEN) \
- (((uint64) (LEN) + ((ALIGNVAL) - 1)) & ~((uint64) ((ALIGNVAL) - 1)))
-
- /* we don't currently need wider versions of the other ALIGN macros */
- #define MAXALIGN64(LEN) TYPEALIGN64(MAXIMUM_ALIGNOF, (LEN))
-
-
- /* ----------------------------------------------------------------
- * Section 6: assertions
- * ----------------------------------------------------------------
- */
-
- /*
- * 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
- */
-
- /*
- * Assert() can be used in both frontend and backend code. In frontend code it
- * just calls the standard assert, if it's available. If use of assertions is
- * not configured, it does nothing.
- */
- #ifndef USE_ASSERT_CHECKING
-
- #define Assert(condition) ((void)true)
- #define AssertMacro(condition) ((void)true)
- #define AssertArg(condition) ((void)true)
- #define AssertState(condition) ((void)true)
- #define AssertPointerAlignment(ptr, bndr) ((void)true)
- #define Trap(condition, errorType) ((void)true)
- #define TrapMacro(condition, errorType) (true)
-
- #elif defined(FRONTEND)
-
- #include <assert.h>
- #define Assert(p) assert(p)
- #define AssertMacro(p) ((void) assert(p))
- #define AssertArg(condition) assert(condition)
- #define AssertState(condition) assert(condition)
- #define AssertPointerAlignment(ptr, bndr) ((void)true)
-
- #else /* USE_ASSERT_CHECKING && !FRONTEND */
-
- /*
- * Trap
- * Generates an exception if the given condition is true.
- */
- #define Trap(condition, errorType) \
- do { \
- if (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) (! (condition) || \
- (ExceptionalCondition(CppAsString(condition), (errorType), \
- __FILE__, __LINE__), 0)))
-
- #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")
-
- /*
- * Check that `ptr' is `bndr' aligned.
- */
- #define AssertPointerAlignment(ptr, bndr) \
- Trap(TYPEALIGN(bndr, (uintptr_t)(ptr)) != (uintptr_t)(ptr), \
- "UnalignedPointer")
-
- #endif /* USE_ASSERT_CHECKING && !FRONTEND */
-
- /*
- * ExceptionalCondition is compiled into the backend whether or not
- * USE_ASSERT_CHECKING is defined, so as to support use of extensions
- * that are built with that #define with a backend that isn't. Hence,
- * we should declare it as long as !FRONTEND.
- */
- #ifndef FRONTEND
- extern void ExceptionalCondition(const char *conditionName,
- const char *errorType,
- const char *fileName, int lineNumber) pg_attribute_noreturn();
- #endif
-
- /*
- * Macros to support compile-time assertion checks.
- *
- * If the "condition" (a compile-time-constant expression) evaluates to false,
- * throw a compile error using the "errmessage" (a string literal).
- *
- * gcc 4.6 and up supports _Static_assert(), but there are bizarre syntactic
- * placement restrictions. These macros make it safe to use as a statement
- * or in an expression, respectively.
- *
- * Otherwise we fall back on a kluge that assumes the compiler will complain
- * about a negative width for a struct bit-field. This will not include a
- * helpful error message, but it beats not getting an error at all.
- */
- #ifndef __cplusplus
- #ifdef HAVE__STATIC_ASSERT
- #define StaticAssertStmt(condition, errmessage) \
- do { _Static_assert(condition, errmessage); } while(0)
- #define StaticAssertExpr(condition, errmessage) \
- ((void) ({ StaticAssertStmt(condition, errmessage); true; }))
- #else /* !HAVE__STATIC_ASSERT */
- #define StaticAssertStmt(condition, errmessage) \
- ((void) sizeof(struct { int static_assert_failure : (condition) ? 1 : -1; }))
- #define StaticAssertExpr(condition, errmessage) \
- StaticAssertStmt(condition, errmessage)
- #endif /* HAVE__STATIC_ASSERT */
- #else /* C++ */
- #if defined(__cpp_static_assert) && __cpp_static_assert >= 200410
- #define StaticAssertStmt(condition, errmessage) \
- static_assert(condition, errmessage)
- #define StaticAssertExpr(condition, errmessage) \
- ({ static_assert(condition, errmessage); })
- #else
- #define StaticAssertStmt(condition, errmessage) \
- do { struct static_assert_struct { int static_assert_failure : (condition) ? 1 : -1; }; } while(0)
- #define StaticAssertExpr(condition, errmessage) \
- ((void) ({ StaticAssertStmt(condition, errmessage); }))
- #endif
- #endif /* C++ */
-
-
- /*
- * Compile-time checks that a variable (or expression) has the specified type.
- *
- * AssertVariableIsOfType() can be used as a statement.
- * AssertVariableIsOfTypeMacro() is intended for use in macros, eg
- * #define foo(x) (AssertVariableIsOfTypeMacro(x, int), bar(x))
- *
- * If we don't have __builtin_types_compatible_p, we can still assert that
- * the types have the same size. This is far from ideal (especially on 32-bit
- * platforms) but it provides at least some coverage.
- */
- #ifdef HAVE__BUILTIN_TYPES_COMPATIBLE_P
- #define AssertVariableIsOfType(varname, typename) \
- StaticAssertStmt(__builtin_types_compatible_p(__typeof__(varname), typename), \
- CppAsString(varname) " does not have type " CppAsString(typename))
- #define AssertVariableIsOfTypeMacro(varname, typename) \
- (StaticAssertExpr(__builtin_types_compatible_p(__typeof__(varname), typename), \
- CppAsString(varname) " does not have type " CppAsString(typename)))
- #else /* !HAVE__BUILTIN_TYPES_COMPATIBLE_P */
- #define AssertVariableIsOfType(varname, typename) \
- StaticAssertStmt(sizeof(varname) == sizeof(typename), \
- CppAsString(varname) " does not have type " CppAsString(typename))
- #define AssertVariableIsOfTypeMacro(varname, typename) \
- (StaticAssertExpr(sizeof(varname) == sizeof(typename), \
- CppAsString(varname) " does not have type " CppAsString(typename)))
- #endif /* HAVE__BUILTIN_TYPES_COMPATIBLE_P */
-
-
- /* ----------------------------------------------------------------
- * Section 7: widely useful macros
- * ----------------------------------------------------------------
- */
- /*
- * Max
- * Return the maximum of two numbers.
- */
- #define Max(x, y) ((x) > (y) ? (x) : (y))
-
- /*
- * Min
- * Return the minimum of two numbers.
- */
- #define Min(x, y) ((x) < (y) ? (x) : (y))
-
- /*
- * Abs
- * Return the absolute value of the argument.
- */
- #define Abs(x) ((x) >= 0 ? (x) : -(x))
-
- /*
- * StrNCpy
- * Like standard library function strncpy(), except that result string
- * is guaranteed to be null-terminated --- that is, at most N-1 bytes
- * of the source string will be kept.
- * Also, the macro returns no result (too hard to do that without
- * evaluating the arguments multiple times, which seems worse).
- *
- * BTW: when you need to copy a non-null-terminated string (like a text
- * datum) and add a null, do not do it with StrNCpy(..., len+1). That
- * might seem to work, but it fetches one byte more than there is in the
- * text object. One fine day you'll have a SIGSEGV because there isn't
- * another byte before the end of memory. Don't laugh, we've had real
- * live bug reports from real live users over exactly this mistake.
- * Do it honestly with "memcpy(dst,src,len); dst[len] = '\0';", instead.
- */
- #define StrNCpy(dst,src,len) \
- do \
- { \
- char * _dst = (dst); \
- Size _len = (len); \
- \
- if (_len > 0) \
- { \
- strncpy(_dst, (src), _len); \
- _dst[_len-1] = '\0'; \
- } \
- } while (0)
-
-
- /* Get a bit mask of the bits set in non-long aligned addresses */
- #define LONG_ALIGN_MASK (sizeof(long) - 1)
-
- /*
- * MemSet
- * Exactly the same as standard library function memset(), but considerably
- * faster for zeroing small word-aligned structures (such as parsetree nodes).
- * This has to be a macro because the main point is to avoid function-call
- * overhead. However, we have also found that the loop is faster than
- * native libc memset() on some platforms, even those with assembler
- * memset() functions. More research needs to be done, perhaps with
- * MEMSET_LOOP_LIMIT tests in configure.
- */
- #define MemSet(start, val, len) \
- do \
- { \
- /* must be void* because we don't know if it is integer aligned yet */ \
- void *_vstart = (void *) (start); \
- int _val = (val); \
- Size _len = (len); \
- \
- if ((((uintptr_t) _vstart) & LONG_ALIGN_MASK) == 0 && \
- (_len & LONG_ALIGN_MASK) == 0 && \
- _val == 0 && \
- _len <= MEMSET_LOOP_LIMIT && \
- /* \
- * If MEMSET_LOOP_LIMIT == 0, optimizer should find \
- * the whole "if" false at compile time. \
- */ \
- MEMSET_LOOP_LIMIT != 0) \
- { \
- long *_start = (long *) _vstart; \
- long *_stop = (long *) ((char *) _start + _len); \
- while (_start < _stop) \
- *_start++ = 0; \
- } \
- else \
- memset(_vstart, _val, _len); \
- } while (0)
-
- /*
- * MemSetAligned is the same as MemSet except it omits the test to see if
- * "start" is word-aligned. This is okay to use if the caller knows a-priori
- * that the pointer is suitably aligned (typically, because he just got it
- * from palloc(), which always delivers a max-aligned pointer).
- */
- #define MemSetAligned(start, val, len) \
- do \
- { \
- long *_start = (long *) (start); \
- int _val = (val); \
- Size _len = (len); \
- \
- if ((_len & LONG_ALIGN_MASK) == 0 && \
- _val == 0 && \
- _len <= MEMSET_LOOP_LIMIT && \
- MEMSET_LOOP_LIMIT != 0) \
- { \
- long *_stop = (long *) ((char *) _start + _len); \
- while (_start < _stop) \
- *_start++ = 0; \
- } \
- else \
- memset(_start, _val, _len); \
- } while (0)
-
-
- /*
- * MemSetTest/MemSetLoop are a variant version that allow all the tests in
- * MemSet to be done at compile time in cases where "val" and "len" are
- * constants *and* we know the "start" pointer must be word-aligned.
- * If MemSetTest succeeds, then it is okay to use MemSetLoop, otherwise use
- * MemSetAligned. Beware of multiple evaluations of the arguments when using
- * this approach.
- */
- #define MemSetTest(val, len) \
- ( ((len) & LONG_ALIGN_MASK) == 0 && \
- (len) <= MEMSET_LOOP_LIMIT && \
- MEMSET_LOOP_LIMIT != 0 && \
- (val) == 0 )
-
- #define MemSetLoop(start, val, len) \
- do \
- { \
- long * _start = (long *) (start); \
- long * _stop = (long *) ((char *) _start + (Size) (len)); \
- \
- while (_start < _stop) \
- *_start++ = 0; \
- } while (0)
-
- /*
- * Macros for range-checking float values before converting to integer.
- * We must be careful here that the boundary values are expressed exactly
- * in the float domain. PG_INTnn_MIN is an exact power of 2, so it will
- * be represented exactly; but PG_INTnn_MAX isn't, and might get rounded
- * off, so avoid using that.
- * The input must be rounded to an integer beforehand, typically with rint(),
- * else we might draw the wrong conclusion about close-to-the-limit values.
- * These macros will do the right thing for Inf, but not necessarily for NaN,
- * so check isnan(num) first if that's a possibility.
- */
- #define FLOAT4_FITS_IN_INT16(num) \
- ((num) >= (float4) PG_INT16_MIN && (num) < -((float4) PG_INT16_MIN))
- #define FLOAT4_FITS_IN_INT32(num) \
- ((num) >= (float4) PG_INT32_MIN && (num) < -((float4) PG_INT32_MIN))
- #define FLOAT4_FITS_IN_INT64(num) \
- ((num) >= (float4) PG_INT64_MIN && (num) < -((float4) PG_INT64_MIN))
- #define FLOAT8_FITS_IN_INT16(num) \
- ((num) >= (float8) PG_INT16_MIN && (num) < -((float8) PG_INT16_MIN))
- #define FLOAT8_FITS_IN_INT32(num) \
- ((num) >= (float8) PG_INT32_MIN && (num) < -((float8) PG_INT32_MIN))
- #define FLOAT8_FITS_IN_INT64(num) \
- ((num) >= (float8) PG_INT64_MIN && (num) < -((float8) PG_INT64_MIN))
-
-
- /* ----------------------------------------------------------------
- * Section 8: random stuff
- * ----------------------------------------------------------------
- */
-
- /*
- * Invert the sign of a qsort-style comparison result, ie, exchange negative
- * and positive integer values, being careful not to get the wrong answer
- * for INT_MIN. The argument should be an integral variable.
- */
- #define INVERT_COMPARE_RESULT(var) \
- ((var) = ((var) < 0) ? 1 : -(var))
-
- /*
- * Use this, not "char buf[BLCKSZ]", to declare a field or local variable
- * holding a page buffer, if that page might be accessed as a page and not
- * just a string of bytes. Otherwise the variable might be under-aligned,
- * causing problems on alignment-picky hardware. (In some places, we use
- * this to declare buffers even though we only pass them to read() and
- * write(), because copying to/from aligned buffers is usually faster than
- * using unaligned buffers.) We include both "double" and "int64" in the
- * union to ensure that the compiler knows the value must be MAXALIGN'ed
- * (cf. configure's computation of MAXIMUM_ALIGNOF).
- */
- typedef union PGAlignedBlock
- {
- char data[BLCKSZ];
- double force_align_d;
- int64 force_align_i64;
- } PGAlignedBlock;
-
- /* Same, but for an XLOG_BLCKSZ-sized buffer */
- typedef union PGAlignedXLogBlock
- {
- char data[XLOG_BLCKSZ];
- double force_align_d;
- int64 force_align_i64;
- } PGAlignedXLogBlock;
-
- /* msb for char */
- #define HIGHBIT (0x80)
- #define IS_HIGHBIT_SET(ch) ((unsigned char)(ch) & HIGHBIT)
-
- /*
- * Support macros for escaping strings. escape_backslash should be true
- * if generating a non-standard-conforming string. Prefixing a string
- * with ESCAPE_STRING_SYNTAX guarantees it is non-standard-conforming.
- * Beware of multiple evaluation of the "ch" argument!
- */
- #define SQL_STR_DOUBLE(ch, escape_backslash) \
- ((ch) == '\'' || ((ch) == '\\' && (escape_backslash)))
-
- #define ESCAPE_STRING_SYNTAX 'E'
-
-
- #define STATUS_OK (0)
- #define STATUS_ERROR (-1)
- #define STATUS_EOF (-2)
- #define STATUS_FOUND (1)
- #define STATUS_WAITING (2)
-
- /*
- * gettext support
- */
-
- #ifndef ENABLE_NLS
- /* stuff we'd otherwise get from <libintl.h> */
- #define gettext(x) (x)
- #define dgettext(d,x) (x)
- #define ngettext(s,p,n) ((n) == 1 ? (s) : (p))
- #define dngettext(d,s,p,n) ((n) == 1 ? (s) : (p))
- #endif
-
- #define _(x) gettext(x)
-
- /*
- * Use this to mark string constants as needing translation at some later
- * time, rather than immediately. This is useful for cases where you need
- * access to the original string and translated string, and for cases where
- * immediate translation is not possible, like when initializing global
- * variables.
- * http://www.gnu.org/software/autoconf/manual/gettext/Special-cases.html
- */
- #define gettext_noop(x) (x)
-
- /*
- * To better support parallel installations of major PostgreSQL
- * versions as well as parallel installations of major library soname
- * versions, we mangle the gettext domain name by appending those
- * version numbers. The coding rule ought to be that wherever the
- * domain name is mentioned as a literal, it must be wrapped into
- * PG_TEXTDOMAIN(). The macros below do not work on non-literals; but
- * that is somewhat intentional because it avoids having to worry
- * about multiple states of premangling and postmangling as the values
- * are being passed around.
- *
- * Make sure this matches the installation rules in nls-global.mk.
- */
- #ifdef SO_MAJOR_VERSION
- #define PG_TEXTDOMAIN(domain) (domain CppAsString2(SO_MAJOR_VERSION) "-" PG_MAJORVERSION)
- #else
- #define PG_TEXTDOMAIN(domain) (domain "-" PG_MAJORVERSION)
- #endif
-
- /*
- * Macro that allows to cast constness and volatile away from an expression, but doesn't
- * allow changing the underlying type. Enforcement of the latter
- * currently only works for gcc like compilers.
- *
- * Please note IT IS NOT SAFE to cast constness away if the result will ever
- * be modified (it would be undefined behaviour). Doing so anyway can cause
- * compiler misoptimizations or runtime crashes (modifying readonly memory).
- * It is only safe to use when the result will not be modified, but API
- * design or language restrictions prevent you from declaring that
- * (e.g. because a function returns both const and non-const variables).
- *
- * Note that this only works in function scope, not for global variables (it'd
- * be nice, but not trivial, to improve that).
- */
- #if defined(HAVE__BUILTIN_TYPES_COMPATIBLE_P)
- #define unconstify(underlying_type, expr) \
- (StaticAssertExpr(__builtin_types_compatible_p(__typeof(expr), const underlying_type), \
- "wrong cast"), \
- (underlying_type) (expr))
- #define unvolatize(underlying_type, expr) \
- (StaticAssertExpr(__builtin_types_compatible_p(__typeof(expr), volatile underlying_type), \
- "wrong cast"), \
- (underlying_type) (expr))
- #else
- #define unconstify(underlying_type, expr) \
- ((underlying_type) (expr))
- #define unvolatize(underlying_type, expr) \
- ((underlying_type) (expr))
- #endif
-
- /* ----------------------------------------------------------------
- * Section 9: system-specific hacks
- *
- * This should be limited to things that absolutely have to be
- * included in every source file. The port-specific header file
- * is usually a better place for this sort of thing.
- * ----------------------------------------------------------------
- */
-
- /*
- * NOTE: this is also used for opening text files.
- * WIN32 treats Control-Z as EOF in files opened in text mode.
- * Therefore, we open files in binary mode on Win32 so we can read
- * literal control-Z. The other affect is that we see CRLF, but
- * that is OK because we can already handle those cleanly.
- */
- #if defined(WIN32) || defined(__CYGWIN__)
- #define PG_BINARY O_BINARY
- #define PG_BINARY_A "ab"
- #define PG_BINARY_R "rb"
- #define PG_BINARY_W "wb"
- #else
- #define PG_BINARY 0
- #define PG_BINARY_A "a"
- #define PG_BINARY_R "r"
- #define PG_BINARY_W "w"
- #endif
-
- /*
- * Provide prototypes for routines not present in a particular machine's
- * standard C library.
- */
-
- #if defined(HAVE_FDATASYNC) && !HAVE_DECL_FDATASYNC
- extern int fdatasync(int fildes);
- #endif
-
- #ifdef HAVE_LONG_LONG_INT
- /* Older platforms may provide strto[u]ll functionality under other names */
- #if !defined(HAVE_STRTOLL) && defined(HAVE___STRTOLL)
- #define strtoll __strtoll
- #define HAVE_STRTOLL 1
- #endif
-
- #if !defined(HAVE_STRTOLL) && defined(HAVE_STRTOQ)
- #define strtoll strtoq
- #define HAVE_STRTOLL 1
- #endif
-
- #if !defined(HAVE_STRTOULL) && defined(HAVE___STRTOULL)
- #define strtoull __strtoull
- #define HAVE_STRTOULL 1
- #endif
-
- #if !defined(HAVE_STRTOULL) && defined(HAVE_STRTOUQ)
- #define strtoull strtouq
- #define HAVE_STRTOULL 1
- #endif
-
- #if defined(HAVE_STRTOLL) && !HAVE_DECL_STRTOLL
- extern long long strtoll(const char *str, char **endptr, int base);
- #endif
-
- #if defined(HAVE_STRTOULL) && !HAVE_DECL_STRTOULL
- extern unsigned long long strtoull(const char *str, char **endptr, int base);
- #endif
- #endif /* HAVE_LONG_LONG_INT */
-
- #if !defined(HAVE_MEMMOVE) && !defined(memmove)
- #define memmove(d, s, c) bcopy(s, d, c)
- #endif
-
- /* no special DLL markers on most ports */
- #ifndef PGDLLIMPORT
- #define PGDLLIMPORT
- #endif
- #ifndef PGDLLEXPORT
- #define PGDLLEXPORT
- #endif
-
- /*
- * The following is used as the arg list for signal handlers. Any ports
- * that take something other than an int argument should override this in
- * their pg_config_os.h file. Note that variable names are required
- * because it is used in both the prototypes as well as the definitions.
- * Note also the long name. We expect that this won't collide with
- * other names causing compiler warnings.
- */
-
- #ifndef SIGNAL_ARGS
- #define SIGNAL_ARGS int postgres_signal_arg
- #endif
-
- /*
- * When there is no sigsetjmp, its functionality is provided by plain
- * setjmp. Incidentally, nothing provides setjmp's functionality in
- * that case. We now support the case only on Windows.
- */
- #ifdef WIN32
- #define sigjmp_buf jmp_buf
- #define sigsetjmp(x,y) setjmp(x)
- #define siglongjmp longjmp
- #endif
-
- /* EXEC_BACKEND defines */
- #ifdef EXEC_BACKEND
- #define NON_EXEC_STATIC
- #else
- #define NON_EXEC_STATIC static
- #endif
-
- /* /port compatibility functions */
- #include "port.h"
-
- #endif /* C_H */
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