YugabyteDB (2.13.1.0-b60, 21121d69985fbf76aa6958d8f04a9bfa936293b5)

//

// Copyright (C) 1999 and onwards Google, Inc.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except

// in compliance with the License.  You may obtain a copy of the License at

//

// http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software distributed under the License

// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

// or implied.  See the License for the specific language governing permissions and limitations

// under the License.

//

// These are weird things we need to do to get this compiling on

// random systems (and on SWIG).

#ifndef YB_GUTIL_PORT_H

#define YB_GUTIL_PORT_H

#include <errno.h>

#include <limits.h>         // So we can set the bounds of our types

#include <stdlib.h>         // for free()

#include <string.h>         // for memcpy()

#if defined(__APPLE__)

#include <unistd.h>         // for getpagesize() on mac

#elif defined(OS_CYGWIN)

#include <malloc.h>         // for memalign()

#endif

#include <type_traits>

#include "yb/gutil/integral_types.h"

// Must happens before inttypes.h inclusion */

#if defined(__APPLE__)

/* From MacOSX's inttypes.h:

 * "C++ implementations should define these macros only when

 *  __STDC_FORMAT_MACROS is defined before <inttypes.h> is included." */

#ifndef __STDC_FORMAT_MACROS

#define __STDC_FORMAT_MACROS

#endif  /* __STDC_FORMAT_MACROS */

#endif  /* __APPLE__ */

/* Default for most OSes */

/* We use SIGPWR since that seems unlikely to be used for other reasons. */

#define GOOGLE_OBSCURE_SIGNAL  SIGPWR

#if defined __linux__ || defined OS_CYGWIN

// _BIG_ENDIAN

#include <endian.h>

// The uint mess:

// mysql.h sets _GNU_SOURCE which sets __USE_MISC in <features.h>

// sys/types.h typedefs uint if __USE_MISC

// mysql typedefs uint if HAVE_UINT not set

// The following typedef is carefully considered, and should not cause

//  any clashes

#if !defined(__USE_MISC)

#if !defined(HAVE_UINT)

#define HAVE_UINT 1

typedef unsigned int uint;

#endif

#if !defined(HAVE_USHORT)

#define HAVE_USHORT 1

typedef unsigned short ushort; // NOLINT

#endif

#if !defined(HAVE_ULONG)

#define HAVE_ULONG 1

typedef unsigned long ulong; // NOLINT

#endif

#endif

#if defined(__cplusplus)

#include <cstddef>              // For _GLIBCXX macros

#endif

#if !defined(HAVE_TLS) && defined(_GLIBCXX_HAVE_TLS) && defined(__x86_64__)

#define HAVE_TLS 1

#endif

#elif defined OS_FREEBSD

// _BIG_ENDIAN

#include <machine/endian.h>

#elif defined OS_SOLARIS

// _BIG_ENDIAN

#include <sys/isa_defs.h>

// Solaris doesn't define sig_t (function taking an int, returning void)

typedef void (*sig_t)(int);

// Solaris only defines strtoll, not strtoq

#define strtoq  strtoll

#define strtouq strtoull

// It doesn't define the posix-standard(?) u_int_16

#include <sys/int_types.h>  // NOLINT(build/include)

typedef uint16_t u_int16_t;

#elif defined __APPLE__

// BIG_ENDIAN

#include <machine/endian.h>  // NOLINT(build/include)

/* Let's try and follow the Linux convention */

#define __BYTE_ORDER  BYTE_ORDER

#define __LITTLE_ENDIAN LITTLE_ENDIAN

#define __BIG_ENDIAN BIG_ENDIAN

#endif

// The following guarenty declaration of the byte swap functions, and

// define __BYTE_ORDER for MSVC

#ifdef _MSC_VER

#include <stdlib.h>  // NOLINT(build/include)

#define __BYTE_ORDER __LITTLE_ENDIAN

#define bswap_16(x) _byteswap_ushort(x)

#define bswap_32(x) _byteswap_ulong(x)

#define bswap_64(x) _byteswap_uint64(x)

#elif defined(__APPLE__)

// Mac OS X / Darwin features

#include <libkern/OSByteOrder.h>

#define bswap_16(x) OSSwapInt16(x)

#define bswap_32(x) OSSwapInt32(x)

#define bswap_64(x) OSSwapInt64(x)

#elif defined(__GLIBC__)

#include <byteswap.h>  // IWYU pragma: export

#else

static inline uint16 bswap_16(uint16 x) {

  return ((x & 0xFF) << 8) | ((x & 0xFF00) >> 8);

}

#define bswap_16(x) bswap_16(x)

static inline uint32 bswap_32(uint32 x) {

  return (((x & 0xFF) << 24) |

          ((x & 0xFF00) << 8) |

          ((x & 0xFF0000) >> 8) |

          ((x & 0xFF000000) >> 24));

}

#define bswap_32(x) bswap_32(x)

static inline uint64 bswap_64(uint64 x) {

  return (((x & GG_ULONGLONG(0xFF)) << 56) |

          ((x & GG_ULONGLONG(0xFF00)) << 40) |

          ((x & GG_ULONGLONG(0xFF0000)) << 24) |

          ((x & GG_ULONGLONG(0xFF000000)) << 8) |

          ((x & GG_ULONGLONG(0xFF00000000)) >> 8) |

          ((x & GG_ULONGLONG(0xFF0000000000)) >> 24) |

          ((x & GG_ULONGLONG(0xFF000000000000)) >> 40) |

          ((x & GG_ULONGLONG(0xFF00000000000000)) >> 56));

}

#define bswap_64(x) bswap_64(x)

#endif

// define the macros IS_LITTLE_ENDIAN or IS_BIG_ENDIAN

// using the above endian defintions from endian.h if

// endian.h was included

#ifdef __BYTE_ORDER

#if __BYTE_ORDER == __LITTLE_ENDIAN

#define IS_LITTLE_ENDIAN

#endif

#if __BYTE_ORDER == __BIG_ENDIAN

#define IS_BIG_ENDIAN

#endif

#else

#if defined(__LITTLE_ENDIAN__)

#define IS_LITTLE_ENDIAN

#elif defined(__BIG_ENDIAN__)

#define IS_BIG_ENDIAN

#endif

// there is also PDP endian ...

#endif  // __BYTE_ORDER

// Define the OS's path separator

#ifdef __cplusplus  // C won't merge duplicate const variables at link time

// Some headers provide a macro for this (GCC's system.h), remove it so that we

// can use our own.

#undef PATH_SEPARATOR

#if defined(OS_WINDOWS)

const char PATH_SEPARATOR = '\\';

#else

const char PATH_SEPARATOR = '/';

#endif

#endif

// Windows has O_BINARY as a flag to open() (like "b" for fopen).

// Linux doesn't need make this distinction.

#if defined __linux__ && !defined O_BINARY

#define O_BINARY 0

#endif

// va_copy portability definitions

#ifdef _MSC_VER

// MSVC doesn't have va_copy yet.

// This is believed to work for 32-bit msvc.  This may not work at all for

// other platforms.

// If va_list uses the single-element-array trick, you will probably get

// a compiler error here.

//

#include <stdarg.h>

inline void va_copy(va_list& a, va_list& b) { // NOLINT

  a = b;

}

// Nor does it have uid_t

typedef int uid_t;

#endif

// Mac OS X / Darwin features

#if defined(__APPLE__)

// For mmap, Linux defines both MAP_ANONYMOUS and MAP_ANON and says MAP_ANON is

// deprecated. In Darwin, MAP_ANON is all there is.

#if !defined MAP_ANONYMOUS

#define MAP_ANONYMOUS MAP_ANON

#endif

// Linux has this in <sys/cdefs.h>

#define __ptr_t void *

// Linux has this in <linux/errno.h>

#define EXFULL      ENOMEM  // not really that great a translation...

// Darwin doesn't have strnlen. No comment.

inline size_t strnlen(const char *s, size_t maxlen) {

  const char* end = (const char *)memchr(s, '\0', maxlen);

  if (end)

    return end - s;

  return maxlen;

}

// Doesn't exist on some versions on macOS; used in google.cc for send() to mean "no flags".

#ifndef MSG_NOSIGNAL

#define MSG_NOSIGNAL 0

#endif

// No SIGPWR on MacOSX.  SIGINFO seems suitably obscure.

#undef GOOGLE_OBSCURE_SIGNAL

#define GOOGLE_OBSCURE_SIGNAL  SIGINFO

#elif defined(OS_CYGWIN)  // Cygwin-specific behavior.

#if defined(__CYGWIN32__)

#define __WORDSIZE 32

#else

// It's probably possible to support 64-bit, but the #defines will need checked.

#error "Cygwin is currently only 32-bit."

#endif

// No signalling on Windows.

#undef GOOGLE_OBSCURE_SIGNAL

#define GOOGLE_OBSCURE_SIGNAL 0

struct stack_t {

  void* ss_sp;

  int ss_flags;

  size_t ss_size;

};

inline int sigaltstack(stack_t* ss, stack_t* oss) { return 0; }

#define PTHREAD_STACK_MIN 0  // Not provided by cygwin

// Scans memory for a character.

// memrchr is used in a few places, but it's linux-specific.

inline void* memrchr(const void* bytes, int find_char, size_t len) {

  const unsigned char* cursor =

      reinterpret_cast<const unsigned char*>(bytes) + len - 1;

  unsigned char actual_char = find_char;

  for (; cursor >= bytes; --cursor) {

    if (*cursor == actual_char) {

      return const_cast<void*>(reinterpret_cast<const void*>(cursor));

    }

  }

  return NULL;

}

#endif

// Klocwork static analysis tool's C/C++ complier kwcc

#if defined(__KLOCWORK__)

#define STATIC_ANALYSIS

#endif // __KLOCWORK__

// Annotate a function indicating the caller must examine the return value.

// Use like:

//   int foo() WARN_UNUSED_RESULT;

// To explicitly ignore a result, see |ignore_result()| in <base/basictypes.h>.

#if defined(__GNUC__)

#define WARN_UNUSED_RESULT __attribute__((warn_unused_result))

#else

#define WARN_UNUSED_RESULT

#endif

// GCC-specific features

#if (defined(__GNUC__) || defined(__APPLE__)) && !defined(SWIG)

//

// Tell the compiler to do printf format string checking if the

// compiler supports it; see the 'format' attribute in

// <http://gcc.gnu.org/onlinedocs/gcc-4.3.0/gcc/Function-Attributes.html>.

//

// N.B.: As the GCC manual states, "[s]ince non-static C++ methods

// have an implicit 'this' argument, the arguments of such methods

// should be counted from two, not one."

//

#define PRINTF_ATTRIBUTE(string_index, first_to_check) \

    __attribute__((__format__ (__printf__, string_index, first_to_check)))

#define SCANF_ATTRIBUTE(string_index, first_to_check) \

    __attribute__((__format__ (__scanf__, string_index, first_to_check)))

//

// Prevent the compiler from padding a structure to natural alignment

//

#define PACKED __attribute__ ((packed))

// Cache line alignment

#if defined(__i386__) || defined(__x86_64__)

#define CACHELINE_SIZE 64

#elif defined(__powerpc64__)

// TODO(user) This is the L1 D-cache line size of our Power7 machines.

// Need to check if this is appropriate for other PowerPC64 systems.

#define CACHELINE_SIZE 128

#elif defined(__aarch64__)

// TODO: confirm whether this is always correct and how exactly we are using this.

// https://github.com/yugabyte/yugabyte-db/issues/9218

#define CACHELINE_SIZE 64

#elif defined(__arm__)

// Cache line sizes for ARM: These values are not strictly correct since

// cache line sizes depend on implementations, not architectures.  There

// are even implementations with cache line sizes configurable at boot

// time.

#if defined(__ARM_ARCH_5T__)

#define CACHELINE_SIZE 32

#elif defined(__ARM_ARCH_7A__)

#define CACHELINE_SIZE 64

#endif

#endif

// This is a NOP if CACHELINE_SIZE is not defined.

#ifdef CACHELINE_SIZE

#define CACHELINE_ALIGNED __attribute__((aligned(CACHELINE_SIZE)))

#else

#define CACHELINE_ALIGNED

#endif

//

// Prevent the compiler from complaining about or optimizing away variables

// that appear unused

// (careful, others e.g. third_party/libxml/xmlversion.h also define this)

#undef ATTRIBUTE_UNUSED

#define ATTRIBUTE_UNUSED __attribute__ ((unused))

// Same as above, but for class members.

// As of 10/2013 this appears to only be supported in Clang/LLVM.

// See http://patchwork.ozlabs.org/patch/232594/ which is not yet committed

// in gcc trunk.

#if defined(__llvm__)

#define ATTRIBUTE_MEMBER_UNUSED ATTRIBUTE_UNUSED

#else

#define ATTRIBUTE_MEMBER_UNUSED

#endif

//

// For functions we want to force inline or not inline.

// Introduced in gcc 3.1.

#define ATTRIBUTE_ALWAYS_INLINE  __attribute__ ((always_inline))

#define HAVE_ATTRIBUTE_ALWAYS_INLINE 1

#define ATTRIBUTE_NOINLINE __attribute__ ((noinline))

#define HAVE_ATTRIBUTE_NOINLINE 1

// For weak functions

#undef ATTRIBUTE_WEAK

#define ATTRIBUTE_WEAK __attribute__ ((weak))

#define HAVE_ATTRIBUTE_WEAK 1

// For deprecated functions or variables, generate a warning at usage sites.

// Verified to work as early as GCC 3.1.1 and clang 3.2 (so we'll assume any

// clang is new enough).

#if defined(__clang__) || \

  (defined(COMPILER_GCC) && \

   (__GNUC__ * 10000 + __GNUC_MINOR__ * 100) >= 30200)

#define ATTRIBUTE_DEPRECATED(msg) __attribute__ ((deprecated (msg) ))

#else

#define ATTRIBUTE_DEPRECATED(msg)

#endif

// Tell the compiler to use "initial-exec" mode for a thread-local variable.

// See http://people.redhat.com/drepper/tls.pdf for the gory details.

#define ATTRIBUTE_INITIAL_EXEC __attribute__ ((tls_model ("initial-exec")))

//

// Tell the compiler that some function parameters should be non-null pointers.

// Note: As the GCC manual states, "[s]ince non-static C++ methods

// have an implicit 'this' argument, the arguments of such methods

// should be counted from two, not one."

//

#define ATTRIBUTE_NONNULL(arg_index) __attribute__((nonnull(arg_index)))

//

// Tell the compiler that a given function never returns

//

#define ATTRIBUTE_NORETURN __attribute__((noreturn))

// Tell AddressSanitizer (or other memory testing tools) to ignore a given

// function. Useful for cases when a function reads random locations on stack,

// calls _exit from a cloned subprocess, deliberately accesses buffer

// out of bounds or does other scary things with memory.

#ifdef ADDRESS_SANITIZER

#define ATTRIBUTE_NO_ADDRESS_SAFETY_ANALYSIS \

    __attribute__((no_address_safety_analysis))

#else

#define ATTRIBUTE_NO_ADDRESS_SAFETY_ANALYSIS

#endif

// Tell ThreadSanitizer to ignore a given function. This can dramatically reduce

// the running time and memory requirements for racy code when TSAN is active.

// GCC does not support this attribute at the time of this writing (GCC 4.8).

// Also a similar macro for AddressSanitizer.

#if defined(__llvm__)

#define ATTRIBUTE_NO_SANITIZE_THREAD \

    __attribute__((no_sanitize_thread))

#define ATTRIBUTE_NO_SANITIZE_ADDRESS \

    __attribute__((no_sanitize("address")))

#define ATTRIBUTE_NO_SANITIZE_UNDEFINED \

    __attribute__((no_sanitize("undefined")))

#else

#define ATTRIBUTE_NO_SANITIZE_THREAD

#define ATTRIBUTE_NO_SANITIZE_ADDRESS

#define ATTRIBUTE_NO_SANITIZE_UNDEFINED

#endif

#ifndef HAVE_ATTRIBUTE_SECTION  // may have been pre-set to 0, e.g. for Darwin

#define HAVE_ATTRIBUTE_SECTION 1

#endif

//

// The legacy prod71 libc does not provide the stack alignment required for use

// of SSE intrinsics.  In order to properly use the intrinsics you need to use

// a trampoline function which aligns the stack prior to calling your code,

// or as of crosstool v10 with gcc 4.2.0 there is an attribute which asks

// gcc to do this for you.

//

// It has also been discovered that crosstool up to and including v10 does not

// provide proper alignment for pthread_once() functions in x86-64 code either.

// Unfortunately gcc does not provide force_align_arg_pointer as an option in

// x86-64 code, so this requires us to always have a trampoline.

//

// For an example of using this see util/hash/adler32*

#if defined(__i386__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 2))

#define ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC __attribute__((force_align_arg_pointer))

#define REQUIRE_STACK_ALIGN_TRAMPOLINE (0)

#elif defined(__i386__) || defined(__x86_64__)

#define REQUIRE_STACK_ALIGN_TRAMPOLINE (1)

#define ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC

#else

#define REQUIRE_STACK_ALIGN_TRAMPOLINE (0)

#define ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC

#endif

//

// Tell the compiler to warn about unused return values for functions declared

// with this macro.  The macro should be used on function declarations

// following the argument list:

//

//   Sprocket* AllocateSprocket() MUST_USE_RESULT;

//

#if defined(SWIG)

#define MUST_USE_RESULT

#elif __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)

#define MUST_USE_RESULT __attribute__ ((warn_unused_result))

#else

#define MUST_USE_RESULT

#endif

// Annotate a virtual method indicating that subclasses must not override it,

// or annotate a class to indicate that it cannot be subclassed.

// Use like:

//   virtual void foo() FINAL;

//   class B FINAL : public A {};

#if defined(COMPILER_MSVC)

// TODO(jered): Change this to "final" when chromium no longer uses MSVC 2010.

#define FINAL sealed

#elif defined(__clang__)

#define FINAL final

#elif defined(COMPILER_GCC) && __cplusplus >= 201103 && \

      (__GNUC__ * 10000 + __GNUC_MINOR__ * 100) >= 40700

// GCC 4.7 supports explicit virtual overrides when C++11 support is enabled.

#define FINAL final

#else

#define FINAL

#endif

#if defined(__GNUC__)

// Defined behavior on some of the uarchs:

// PREFETCH_HINT_T0:

//   prefetch to all levels of the hierarchy (except on p4: prefetch to L2)

// PREFETCH_HINT_NTA:

//   p4: fetch to L2, but limit to 1 way (out of the 8 ways)

//   core: skip L2, go directly to L1

//   k8 rev E and later: skip L2, can go to either of the 2-ways in L1

enum PrefetchHint {

  PREFETCH_HINT_T0 = 3,  // More temporal locality

  PREFETCH_HINT_T1 = 2,

  PREFETCH_HINT_T2 = 1,  // Less temporal locality

  PREFETCH_HINT_NTA = 0  // No temporal locality

};

#else

// prefetch is a no-op for this target. Feel free to add more sections above.

#endif

extern inline void prefetch(const char *x, int hint) {

#if defined(__llvm__)

  // In the gcc version of prefetch(), hint is only a constant _after_ inlining

  // (assumed to have been successful).  llvm views things differently, and

  // checks constant-ness _before_ inlining.  This leads to compilation errors

  // with using the other version of this code with llvm.

  //

  // One way round this is to use a switch statement to explicitly match

  // prefetch hint enumerations, and invoke __builtin_prefetch for each valid

  // value.  llvm's optimization removes the switch and unused case statements

  // after inlining, so that this boils down in the end to the same as for gcc;

  // that is, a single inlined prefetchX instruction.

  //

  // Note that this version of prefetch() cannot verify constant-ness of hint.

  // If client code calls prefetch() with a variable value for hint, it will

  // receive the full expansion of the switch below, perhaps also not inlined.

  // This should however not be a problem in the general case of well behaved

  // caller code that uses the supplied prefetch hint enumerations.

  switch (hint) {

    case PREFETCH_HINT_T0:

      __builtin_prefetch(x, 0, PREFETCH_HINT_T0);

      break;

    case PREFETCH_HINT_T1:

      __builtin_prefetch(x, 0, PREFETCH_HINT_T1);

      break;

    case PREFETCH_HINT_T2:

      __builtin_prefetch(x, 0, PREFETCH_HINT_T2);

      break;

    case PREFETCH_HINT_NTA:

      __builtin_prefetch(x, 0, PREFETCH_HINT_NTA);

      break;

    default:

      __builtin_prefetch(x);

      break;

  }

#elif defined(__GNUC__)

  #if !defined(__i386) || defined(__SSE__)

    if (__builtin_constant_p(hint)) {

      __builtin_prefetch(x, 0, hint);

    } else {

      // Defaults to PREFETCH_HINT_T0

      __builtin_prefetch(x);

    }

  #else

    // We want a __builtin_prefetch, but we build with the default -march=i386

    // where __builtin_prefetch quietly turns into nothing.

    // Once we crank up to -march=pentium3 or higher the __SSE__

    // clause above will kick in with the builtin.

    // -- mec 2006-06-06

    if (hint == PREFETCH_HINT_NTA)

      __asm__ __volatile__("prefetchnta (%0)" : : "r"(x));

  #endif

#else

  // You get no effect.  Feel free to add more sections above.

#endif

}

#ifdef __cplusplus

// prefetch intrinsic (bring data to L1 without polluting L2 cache)

extern inline void prefetch(const char *x) {

  return prefetch(x, 0);

}

#endif  // ifdef __cplusplus

//

// GCC can be told that a certain branch is not likely to be taken (for

// instance, a CHECK failure), and use that information in static analysis.

// Giving it this information can help it optimize for the common case in

// the absence of better information (ie. -fprofile-arcs).

//

#if defined(__GNUC__)

#define PREDICT_FALSE(x) (__builtin_expect(
x1.48G
, 0))

#define PREDICT_TRUE(x) (__builtin_expect(!!(
x76.0M
), 1))

#else

#define PREDICT_FALSE(x) x

#define PREDICT_TRUE(x) x

#endif

//

// Tell GCC that a function is hot or cold. GCC can use this information to

// improve static analysis, i.e. a conditional branch to a cold function

// is likely to be not-taken.

// This annotation is used for function declarations, e.g.:

//   int foo() ATTRIBUTE_HOT;

//

#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)

#define ATTRIBUTE_HOT __attribute__ ((hot))

#define ATTRIBUTE_COLD __attribute__ ((cold))

#else

#define ATTRIBUTE_HOT

#define ATTRIBUTE_COLD

#endif

#define FTELLO ftello

#define FSEEKO fseeko

#if !defined(__cplusplus) && !defined(__APPLE__) && !defined(OS_CYGWIN)

// stdlib.h only declares this in C++, not in C, so we declare it here.

// Also make sure to avoid declaring it on platforms which don't support it.

extern int posix_memalign(void **memptr, size_t alignment, size_t size);

#endif

inline void *aligned_malloc(size_t size, int minimum_alignment) {

#if defined(__APPLE__)

  // mac lacks memalign(), posix_memalign(), however, according to

  // http://stackoverflow.com/questions/196329/osx-lacks-memalign

  // mac allocs are already 16-byte aligned.

  if (minimum_alignment <= 16)

    return malloc(size);

  // next, try to return page-aligned memory. perhaps overkill

  if (minimum_alignment <= getpagesize())

    return valloc(size);

  // give up

  return NULL;

#elif defined(OS_CYGWIN)

  return memalign(minimum_alignment, size);

#else  // !__APPLE__ && !OS_CYGWIN

  void *ptr = NULL;

  if (posix_memalign(&ptr, minimum_alignment, size) != 0)

    return NULL;

  else

    return ptr;

#endif

}

inline void aligned_free(void *aligned_memory) {

  free(aligned_memory);

}

#else   // not GCC

#define PRINTF_ATTRIBUTE(string_index, first_to_check)

#define SCANF_ATTRIBUTE(string_index, first_to_check)

#define PACKED

#define CACHELINE_ALIGNED

#define ATTRIBUTE_UNUSED

#define ATTRIBUTE_ALWAYS_INLINE

#define ATTRIBUTE_NOINLINE

#define ATTRIBUTE_HOT

#define ATTRIBUTE_COLD

#define ATTRIBUTE_WEAK

#define HAVE_ATTRIBUTE_WEAK 0

#define ATTRIBUTE_INITIAL_EXEC

#define ATTRIBUTE_NONNULL(arg_index)

#define ATTRIBUTE_NORETURN

#define ATTRIBUTE_STACK_ALIGN_FOR_OLD_LIBC

#define REQUIRE_STACK_ALIGN_TRAMPOLINE (0)

#define MUST_USE_RESULT

extern inline void prefetch(const char *x) {}

#define PREDICT_FALSE(x) x

#define PREDICT_TRUE(x) x

// These should be redefined appropriately if better alternatives to

// ftell/fseek exist in the compiler

#define FTELLO ftell

#define FSEEKO fseek

#endif  // GCC

//

// Provides a char array with the exact same alignment as another type. The

// first parameter must be a complete type, the second parameter is how many

// of that type to provide space for.

//

//   ALIGNED_CHAR_ARRAY(struct stat, 16) storage_;

//

#if defined(__cplusplus)

#undef ALIGNED_CHAR_ARRAY

// Because MSVC and older GCCs require that the argument to their alignment

// construct to be a literal constant integer, we use a template instantiated

// at all the possible powers of two.

#ifndef SWIG

template<int alignment, int size> struct AlignType { };

template<int size> struct AlignType<0, size> { typedef char result[size]; };

#if defined(_MSC_VER)

#define BASE_PORT_H_ALIGN_ATTRIBUTE(X) __declspec(align(X))

#define BASE_PORT_H_ALIGN_OF(T) __alignof(T)

#elif defined(__GNUC__)

#define BASE_PORT_H_ALIGN_ATTRIBUTE(X) __attribute__((aligned(X)))

#define BASE_PORT_H_ALIGN_OF(T) __alignof__(T)

#endif

#if defined(BASE_PORT_H_ALIGN_ATTRIBUTE)

#define BASE_PORT_H_ALIGNTYPE_TEMPLATE(X) \

  template<int size> struct AlignType<X, size> { \

    typedef BASE_PORT_H_ALIGN_ATTRIBUTE(X) char result[size]; \

  }

BASE_PORT_H_ALIGNTYPE_TEMPLATE(1);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(2);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(4);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(8);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(16);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(32);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(64);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(128);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(256);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(512);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(1024);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(2048);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(4096);

BASE_PORT_H_ALIGNTYPE_TEMPLATE(8192);

// Any larger and MSVC++ will complain.

#define ALIGNED_CHAR_ARRAY(T, Size) \

  typename AlignType<BASE_PORT_H_ALIGN_OF(T), sizeof(T) * Size>::result

#undef BASE_PORT_H_ALIGNTYPE_TEMPLATE

#undef BASE_PORT_H_ALIGN_ATTRIBUTE

#else  // defined(BASE_PORT_H_ALIGN_ATTRIBUTE)

#define ALIGNED_CHAR_ARRAY you_must_define_ALIGNED_CHAR_ARRAY_for_your_compiler_in_base_port_h

#endif // defined(BASE_PORT_H_ALIGN_ATTRIBUTE)

#else  // !SWIG

// SWIG can't represent alignment and doesn't care about alignment on data

// members (it works fine without it).

template<typename Size>

struct AlignType { typedef char result[Size]; };

#define ALIGNED_CHAR_ARRAY(T, Size) AlignType<Size * sizeof(T)>::result

#endif // !SWIG

#else  // __cpluscplus

#define ALIGNED_CHAR_ARRAY ALIGNED_CHAR_ARRAY_is_not_available_without_Cplusplus

#endif // __cplusplus

#ifdef _MSC_VER     /* if Visual C++ */

// This compiler flag can be easily overlooked on MSVC.

// _CHAR_UNSIGNED gets set with the /J flag.

#ifndef _CHAR_UNSIGNED

#error chars must be unsigned! Use the /J flag on the compiler command line. // NOLINT

#endif

// MSVC is a little hyper-active in its warnings

// Signed vs. unsigned comparison is ok.

#pragma warning(disable : 4018 )

// We know casting from a long to a char may lose data

#pragma warning(disable : 4244 )

// Don't need performance warnings about converting ints to bools

#pragma warning(disable : 4800 )

// Integral constant overflow is apparently ok too

// for example:

//  short k;  int n;

//  k = k + n;

#pragma warning(disable : 4307 )

// It's ok to use this* in constructor

// Example:

//  class C {

//   Container cont_;

//   C() : cont_(this) { ...

#pragma warning(disable : 4355 )

// Truncating from double to float is ok

#pragma warning(disable : 4305 )

#include <winsock2.h>

#include <assert.h>

#include <windows.h>

#undef ERROR

#include <float.h>  // for nextafter functionality on windows

#include <math.h>  // for HUGE_VAL

#ifndef HUGE_VALF

#define HUGE_VALF (static_cast<float>(HUGE_VAL))

#endif

namespace std {}  // Avoid error if we didn't see std.

using namespace std; // NOLINT

// VC++ doesn't understand "uint"

#ifndef HAVE_UINT

#define HAVE_UINT 1

typedef unsigned int uint;

#endif

// VC++ doesn't understand "ssize_t"

#ifndef HAVE_SSIZET

#define HAVE_SSIZET 1

// The following correctly defines ssize_t on most (all?) VC++ versions:

//   #include <BaseTsd.h>

//   typedef SSIZE_T ssize_t;

// However, several projects in googleclient already use plain 'int', e.g.,

//   googleclient/posix/unistd.h

//   googleclient/earth/client/libs/base/types.h

// so to avoid conflicts with those definitions, we do the same here.

typedef int ssize_t;

#endif

#define strtoq   _strtoi64

#define strtouq  _strtoui64

#define strtoll  _strtoi64

#define strtoull _strtoui64

#define atoll    _atoi64

// VC++ 6 and before ship without an ostream << operator for 64-bit ints

#if (_MSC_VER <= 1200)

#include <iosfwd>

using std::ostream;

inline ostream& operator<< (ostream& os, const unsigned __int64& num ) {

  // Fake operator; doesn't actually do anything.

  LOG(FATAL) << "64-bit ostream operator << not supported in VC++ 6";

  return os;

}

#endif

// You say tomato, I say atotom

#define PATH_MAX MAX_PATH

// You say tomato, I say _tomato

#define vsnprintf _vsnprintf

#define snprintf _snprintf

#define strcasecmp _stricmp

#define strncasecmp _strnicmp

#define nextafter _nextafter

#define hypot _hypot

#define hypotf _hypotf

#define strdup _strdup

#define tempnam _tempnam

#define chdir  _chdir

#define getcwd _getcwd

#define putenv  _putenv

// You say tomato, I say toma

#define random() rand()

#define srandom(x) srand(x)

// You say juxtapose, I say transpose

#define bcopy(s, d, n) memcpy(d, s, n)

inline void *aligned_malloc(size_t size, int minimum_alignment) {

  return _aligned_malloc(size, minimum_alignment);

}

inline void aligned_free(void *aligned_memory) {

  _aligned_free(aligned_memory);

}

// ----- BEGIN VC++ STUBS & FAKE DEFINITIONS ---------------------------------

// See http://en.wikipedia.org/wiki/IEEE_754 for details of

// floating point format.

enum {

  FP_NAN,  //  is "Not a Number"

  FP_INFINITE,  //  is either plus or minus infinity.

  FP_ZERO,

  FP_SUBNORMAL,  // is too small to be represented in normalized format.

  FP_NORMAL  // if nothing of the above is correct that it must be a

  // normal floating-point number.

};

inline int fpclassify_double(double x) {

  const int float_point_class = _fpclass(x);

  int c99_class;

  switch  (float_point_class) {

  case _FPCLASS_SNAN:  // Signaling NaN

  case _FPCLASS_QNAN:  // Quiet NaN

    c99_class = FP_NAN;

    break;

  case _FPCLASS_NZ:  // Negative zero ( -0)

  case _FPCLASS_PZ:  // Positive 0 (+0)

    c99_class = FP_ZERO;

    break;

  case _FPCLASS_NINF:  // Negative infinity ( -INF)

  case _FPCLASS_PINF:  // Positive infinity (+INF)

    c99_class = FP_INFINITE;

    break;

  case _FPCLASS_ND:  // Negative denormalized

  case _FPCLASS_PD:  // Positive denormalized

    c99_class = FP_SUBNORMAL;

    break;

  case _FPCLASS_NN:  // Negative normalized non-zero

  case _FPCLASS_PN:  // Positive normalized non-zero

    c99_class = FP_NORMAL;

    break;

  default:

    c99_class = FP_NAN;  // Should never happen

    break;

  }

  return  c99_class;

}

// This function handle the special subnormal case for float; it will

// become a normal number while casting to double.

// bit_cast is avoided to simplify dependency and to create a code that is

// easy to deploy in C code

inline int fpclassify_float(float x) {

  uint32 bitwise_representation;

  memcpy(&bitwise_representation, &x, 4);

  if ((bitwise_representation & 0x7f800000) == 0 &&

      (bitwise_representation & 0x007fffff) != 0)

    return FP_SUBNORMAL;

  return fpclassify_double(x);

}

//

// This define takes care of the denormalized float; the casting to

// double make it a normal number

#define fpclassify(x) ((sizeof(x) == sizeof(float)) ? fpclassify_float(x) : fpclassify_double(x))

#define isnan _isnan

inline int isinf(double x) {

  const int float_point_class = _fpclass(x);

  if (float_point_class == _FPCLASS_PINF) return 1;

  if (float_point_class == _FPCLASS_NINF) return -1;

  return 0;

}

// #include "yb/conflict-signal.h"

typedef void (*sig_t)(int);

// These actually belong in errno.h but there's a name confilict in errno

// on WinNT. They (and a ton more) are also found in Winsock2.h, but

// if'd out under NT. We need this subset at minimum.

#define EXFULL      ENOMEM  // not really that great a translation...

// The following are already defined in VS2010.

#if (_MSC_VER < 1600)

#define EWOULDBLOCK WSAEWOULDBLOCK

#ifndef PTHREADS_REDHAT_WIN32

#define ETIMEDOUT   WSAETIMEDOUT

#endif

#define ENOTSOCK    WSAENOTSOCK

#define EINPROGRESS WSAEINPROGRESS

#define ECONNRESET  WSAECONNRESET

#endif

//

// Really from <string.h>

//

inline void bzero(void *s, int n) {

  memset(s, 0, n);

}

// From glob.h

#define __ptr_t   void *

// Defined all over the place.

typedef int pid_t;

// From stat.h

typedef unsigned int mode_t;

// u_int16_t, int16_t don't exist in MSVC

typedef unsigned short u_int16_t; // NOLINT

typedef short int16_t; // NOLINT

// ----- END VC++ STUBS & FAKE DEFINITIONS ----------------------------------

#endif  // _MSC_VER

#ifdef STL_MSVC  // not always the same as _MSC_VER

#include "yb/base/port_hash.h"

#else

struct PortableHashBase { };

#endif

#if defined(OS_WINDOWS) || defined(__APPLE__)

// gethostbyname() *is* thread-safe for Windows native threads. It is also

// safe on Mac OS X, where it uses thread-local storage, even though the

// manpages claim otherwise. For details, see

// http://lists.apple.com/archives/Darwin-dev/2006/May/msg00008.html

#else

// gethostbyname() is not thread-safe.  So disallow its use.  People

// should either use the HostLookup::Lookup*() methods, or gethostbyname_r()

#define gethostbyname gethostbyname_is_not_thread_safe_DO_NOT_USE

#endif

// create macros in which the programmer should enclose all specializations

// for hash_maps and hash_sets. This is necessary since these classes are not

// STL standardized. Depending on the STL implementation they are in different

// namespaces. Right now the right namespace is passed by the Makefile

// Examples: gcc3: -DHASH_NAMESPACE=__gnu_cxx

//           icc:  -DHASH_NAMESPACE=std

//           gcc2: empty

#ifndef HASH_NAMESPACE

#  define HASH_NAMESPACE_DECLARATION_START

#  define HASH_NAMESPACE_DECLARATION_END

#else

#  define HASH_NAMESPACE_DECLARATION_START  namespace HASH_NAMESPACE {

#  define HASH_NAMESPACE_DECLARATION_END    }

#endif

// Our STL-like classes use __STD.

#if defined(__GNUC__) || defined(__APPLE__) || defined(_MSC_VER)

#define __STD std

#endif

#if defined __GNUC__

#define STREAM_SET(s, bit) (s).setstate(ios_base::bit)

#define STREAM_SETF(s, flag) (s).setf(ios_base::flag)

#else

#define STREAM_SET(s, bit) (s).set(ios::bit)

#define STREAM_SETF(s, flag) (s).setf(ios::flag)

#endif

// Portable handling of unaligned loads, stores, and copies.

// On some platforms, like ARM, the copy functions can be more efficient

// then a load and a store.

#if defined(__i386) || \

    defined(ARCH_ATHLON) || \

    defined(__x86_64__) || \

    defined(_ARCH_PPC) || \

    defined(__aarch64__)

// x86 and x86-64 can perform unaligned loads/stores directly;

// modern PowerPC hardware can also do unaligned integer loads and stores;

// but note: the FPU still sends unaligned loads and stores to a trap handler!

#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))

#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))

#define UNALIGNED_LOAD64(_p) (*reinterpret_cast<const uint64 *>(_p))

#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))

#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))

#define UNALIGNED_STORE64(_p, _val) (*reinterpret_cast<uint64 *>(_p) = (_val))

#elif defined(__arm__) && \

      !defined(__ARM_ARCH_5__) && \

      !defined(__ARM_ARCH_5T__) && \

      !defined(__ARM_ARCH_5TE__) && \

      !defined(__ARM_ARCH_5TEJ__) && \

      !defined(__ARM_ARCH_6__) && \

      !defined(__ARM_ARCH_6J__) && \

      !defined(__ARM_ARCH_6K__) && \

      !defined(__ARM_ARCH_6Z__) && \

      !defined(__ARM_ARCH_6ZK__) && \

      !defined(__ARM_ARCH_6T2__)

// ARMv7 and newer support native unaligned accesses, but only of 16-bit

// and 32-bit values (not 64-bit); older versions either raise a fatal signal,

// do an unaligned read and rotate the words around a bit, or do the reads very

// slowly (trip through kernel mode). There's no simple #define that says just

// "ARMv7 or higher", so we have to filter away all ARMv5 and ARMv6

// sub-architectures. Newer gcc (>= 4.6) set an __ARM_FEATURE_ALIGNED #define,

// so in time, maybe we can move on to that.

//

// This is a mess, but there's not much we can do about it.

#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))

#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))

#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))

#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))

// TODO(user): NEON supports unaligned 64-bit loads and stores.

// See if that would be more efficient on platforms supporting it,

// at least for copies.

inline uint64 UNALIGNED_LOAD64(const void *p) {

  uint64 t;

  memcpy(&t, p, sizeof t);

  return t;

}

inline void UNALIGNED_STORE64(void *p, uint64 v) {