ydb/util/system/defaults.h

#pragma once

#include "platform.h"

#if defined _unix_
    #define LOCSLASH_C '/'
    #define LOCSLASH_S "/"
#else
    #define LOCSLASH_C '\\'
    #define LOCSLASH_S "\\"
#endif // _unix_

#if defined(__INTEL_COMPILER) && defined(__cplusplus)
    #include <new>
#endif

// low and high parts of integers
#if !defined(_win_)
    #include <sys/param.h>
#endif

#if defined(BSD) || defined(_android_)

    #if defined(BSD)
        #include <machine/endian.h>
    #endif

    #if defined(_android_)
        #include <endian.h>
    #endif

    #if (BYTE_ORDER == LITTLE_ENDIAN)
        #define _little_endian_
    #elif (BYTE_ORDER == BIG_ENDIAN)
        #define _big_endian_
    #else
        #error unknown endian not supported
    #endif

#elif (defined(_sun_) && !defined(__i386__)) || defined(_hpux_) || defined(WHATEVER_THAT_HAS_BIG_ENDIAN)
    #define _big_endian_
#else
    #define _little_endian_
#endif

// alignment
#if (defined(_sun_) && !defined(__i386__)) || defined(_hpux_) || defined(__alpha__) || defined(__ia64__) || defined(WHATEVER_THAT_NEEDS_ALIGNING_QUADS)
    #define _must_align8_
#endif

#if (defined(_sun_) && !defined(__i386__)) || defined(_hpux_) || defined(__alpha__) || defined(__ia64__) || defined(WHATEVER_THAT_NEEDS_ALIGNING_LONGS)
    #define _must_align4_
#endif

#if (defined(_sun_) && !defined(__i386__)) || defined(_hpux_) || defined(__alpha__) || defined(__ia64__) || defined(WHATEVER_THAT_NEEDS_ALIGNING_SHORTS)
    #define _must_align2_
#endif

#if defined(__GNUC__)
    #define alias_hack __attribute__((__may_alias__))
#endif

#ifndef alias_hack
    #define alias_hack
#endif

#include "types.h"

#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
    #define PRAGMA(x) _Pragma(#x)
    #define RCSID(idstr) PRAGMA(comment(exestr, idstr))
#else
    #define RCSID(idstr) static const char rcsid[] = idstr
#endif

#include "compiler.h"

#ifdef _win_
    #include <malloc.h>
#elif defined(_sun_)
    #include <alloca.h>
#endif

#ifdef NDEBUG
    #define Y_IF_DEBUG(X)
    #ifdef __cplusplus
constexpr bool Y_IS_DEBUG_BUILD = false;
    #endif
#else
    #define Y_IF_DEBUG(X) X
    #ifdef __cplusplus
constexpr bool Y_IS_DEBUG_BUILD = true;
    #endif
#endif

/**
 * @def Y_ARRAY_SIZE
 *
 * This macro is needed to get number of elements in a statically allocated fixed size array. The
 * expression is a compile-time constant and therefore can be used in compile time computations.
 *
 * @code
 * enum ENumbers {
 *     EN_ONE,
 *     EN_TWO,
 *     EN_SIZE
 * }
 *
 * const char* NAMES[] = {
 *     "one",
 *     "two"
 * }
 *
 * static_assert(Y_ARRAY_SIZE(NAMES) == EN_SIZE, "you should define `NAME` for each enumeration");
 * @endcode
 *
 * This macro also catches type errors. If you see a compiler error like "warning: division by zero
 * is undefined" when using `Y_ARRAY_SIZE` then you are probably giving it a pointer.
 *
 * Since all of our code is expected to work on a 64 bit platform where pointers are 8 bytes we may
 * falsefully accept pointers to types of sizes that are divisors of 8 (1, 2, 4 and 8).
 */
#if defined(__cplusplus)
    #include <util/generic/array_size.h>
#else
    #undef Y_ARRAY_SIZE
    #define Y_ARRAY_SIZE(arr) \
        ((sizeof(arr) / sizeof((arr)[0])) / static_cast<size_t>(!(sizeof(arr) % sizeof((arr)[0]))))
#endif

#undef Y_ARRAY_BEGIN
#define Y_ARRAY_BEGIN(arr) (arr)

#undef Y_ARRAY_END
#define Y_ARRAY_END(arr) ((arr) + Y_ARRAY_SIZE(arr))

/**
 * Concatenates two symbols, even if one of them is itself a macro.
 */
#define Y_CAT(X, Y) Y_CAT_I(X, Y)
#define Y_CAT_I(X, Y) Y_CAT_II(X, Y)
#define Y_CAT_II(X, Y) X##Y

#define Y_STRINGIZE(X) UTIL_PRIVATE_STRINGIZE_AUX(X)
#define UTIL_PRIVATE_STRINGIZE_AUX(X) #X

#if defined(__COUNTER__)
    #define Y_GENERATE_UNIQUE_ID(N) Y_CAT(N, __COUNTER__)
#endif

#if !defined(Y_GENERATE_UNIQUE_ID)
    #define Y_GENERATE_UNIQUE_ID(N) Y_CAT(N, __LINE__)
#endif

#define NPOS ((size_t)-1)