text: // Copyright 2005, Google Inc.
  // All rights reserved.
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  //
  // Authors: wan@google.com (Zhanyong Wan)
  //
  // Low-level types and utilities for porting Google Test to various
  // platforms.  They are subject to change without notice.  DO NOT USE
  // THEM IN USER CODE.
  //
  // This file is fundamental to Google Test.  All other Google Test source
  // files are expected to #include this.  Therefore, it cannot #include
  // any other Google Test header.
  
  #ifndef GTEST_INCLUDE_GTEST_INTERNAL_GTEST_PORT_H_
  #define GTEST_INCLUDE_GTEST_INTERNAL_GTEST_PORT_H_
  
  // The user can define the following macros in the build script to
  // control Google Test's behavior.  If the user doesn't define a macro
  // in this list, Google Test will define it.
  //
  //   GTEST_HAS_CLONE          - Define it to 1/0 to indicate that clone(2)
  //                              is/isn't available.
  //   GTEST_HAS_EXCEPTIONS     - Define it to 1/0 to indicate that exceptions
  //                              are enabled.
  //   GTEST_HAS_GLOBAL_STRING  - Define it to 1/0 to indicate that ::string
  //                              is/isn't available (some systems define
  //                              ::string, which is different to std::string).
  //   GTEST_HAS_GLOBAL_WSTRING - Define it to 1/0 to indicate that ::string
  //                              is/isn't available (some systems define
  //                              ::wstring, which is different to std::wstring).
  //   GTEST_HAS_POSIX_RE       - Define it to 1/0 to indicate that POSIX regular
  //                              expressions are/aren't available.
  //   GTEST_HAS_PTHREAD        - Define it to 1/0 to indicate that <pthread.h>
  //                              is/isn't available.
  //   GTEST_HAS_RTTI           - Define it to 1/0 to indicate that RTTI is/isn't
  //                              enabled.
  //   GTEST_HAS_STD_WSTRING    - Define it to 1/0 to indicate that
  //                              std::wstring does/doesn't work (Google Test can
  //                              be used where std::wstring is unavailable).
  //   GTEST_HAS_TR1_TUPLE      - Define it to 1/0 to indicate tr1::tuple
  //                              is/isn't available.
  //   GTEST_HAS_SEH            - Define it to 1/0 to indicate whether the
  //                              compiler supports Microsoft's "Structured
  //                              Exception Handling".
  //   GTEST_HAS_STREAM_REDIRECTION
  //                            - Define it to 1/0 to indicate whether the
  //                              platform supports I/O stream redirection using
  //                              dup() and dup2().
  //   GTEST_USE_OWN_TR1_TUPLE  - Define it to 1/0 to indicate whether Google
  //                              Test's own tr1 tuple implementation should be
  //                              used.  Unused when the user sets
  //                              GTEST_HAS_TR1_TUPLE to 0.
  //   GTEST_LANG_CXX11         - Define it to 1/0 to indicate that Google Test
  //                              is building in C++11/C++98 mode.
  //   GTEST_LINKED_AS_SHARED_LIBRARY
  //                            - Define to 1 when compiling tests that use
  //                              Google Test as a shared library (known as
  //                              DLL on Windows).
  //   GTEST_CREATE_SHARED_LIBRARY
  //                            - Define to 1 when compiling Google Test itself
  //                              as a shared library.
  
  // This header defines the following utilities:
  //
  // Macros indicating the current platform (defined to 1 if compiled on
  // the given platform; otherwise undefined):
  //   GTEST_OS_AIX      - IBM AIX
  //   GTEST_OS_CYGWIN   - Cygwin
  //   GTEST_OS_HPUX     - HP-UX
  //   GTEST_OS_LINUX    - Linux
  //     GTEST_OS_LINUX_ANDROID - Google Android
  //   GTEST_OS_MAC      - Mac OS X
  //     GTEST_OS_IOS    - iOS
  //       GTEST_OS_IOS_SIMULATOR - iOS simulator
  //   GTEST_OS_NACL     - Google Native Client (NaCl)
  //   GTEST_OS_OPENBSD  - OpenBSD
  //   GTEST_OS_QNX      - QNX
  //   GTEST_OS_SOLARIS  - Sun Solaris
  //   GTEST_OS_SYMBIAN  - Symbian
  //   GTEST_OS_WINDOWS  - Windows (Desktop, MinGW, or Mobile)
  //     GTEST_OS_WINDOWS_DESKTOP  - Windows Desktop
  //     GTEST_OS_WINDOWS_MINGW    - MinGW
  //     GTEST_OS_WINDOWS_MOBILE   - Windows Mobile
  //   GTEST_OS_ZOS      - z/OS
  //
  // Among the platforms, Cygwin, Linux, Max OS X, and Windows have the
  // most stable support.  Since core members of the Google Test project
  // don't have access to other platforms, support for them may be less
  // stable.  If you notice any problems on your platform, please notify
  // googletestframework@googlegroups.com (patches for fixing them are
  // even more welcome!).
  //
  // Note that it is possible that none of the GTEST_OS_* macros are defined.
  //
  // Macros indicating available Google Test features (defined to 1 if
  // the corresponding feature is supported; otherwise undefined):
  //   GTEST_HAS_COMBINE      - the Combine() function (for value-parameterized
  //                            tests)
  //   GTEST_HAS_DEATH_TEST   - death tests
  //   GTEST_HAS_PARAM_TEST   - value-parameterized tests
  //   GTEST_HAS_TYPED_TEST   - typed tests
  //   GTEST_HAS_TYPED_TEST_P - type-parameterized tests
  //   GTEST_USES_POSIX_RE    - enhanced POSIX regex is used. Do not confuse with
  //                            GTEST_HAS_POSIX_RE (see above) which users can
  //                            define themselves.
  //   GTEST_USES_SIMPLE_RE   - our own simple regex is used;
  //                            the above two are mutually exclusive.
  //   GTEST_CAN_COMPARE_NULL - accepts untyped NULL in EXPECT_EQ().
  //
  // Macros for basic C++ coding:
  //   GTEST_AMBIGUOUS_ELSE_BLOCKER_ - for disabling a gcc warning.
  //   GTEST_ATTRIBUTE_UNUSED_  - declares that a class' instances or a
  //                              variable don't have to be used.
  //   GTEST_DISALLOW_ASSIGN_   - disables operator=.
  //   GTEST_DISALLOW_COPY_AND_ASSIGN_ - disables copy ctor and operator=.
  //   GTEST_MUST_USE_RESULT_   - declares that a function's result must be used.
  //
  // Synchronization:
  //   Mutex, MutexLock, ThreadLocal, GetThreadCount()
  //                  - synchronization primitives.
  //   GTEST_IS_THREADSAFE - defined to 1 to indicate that the above
  //                         synchronization primitives have real implementations
  //                         and Google Test is thread-safe; or 0 otherwise.
  //
  // Template meta programming:
  //   is_pointer     - as in TR1; needed on Symbian and IBM XL C/C++ only.
  //   IteratorTraits - partial implementation of std::iterator_traits, which
  //                    is not available in libCstd when compiled with Sun C++.
  //
  // Smart pointers:
  //   scoped_ptr     - as in TR2.
  //
  // Regular expressions:
  //   RE             - a simple regular expression class using the POSIX
  //                    Extended Regular Expression syntax on UNIX-like
  //                    platforms, or a reduced regular exception syntax on
  //                    other platforms, including Windows.
  //
  // Logging:
  //   GTEST_LOG_()   - logs messages at the specified severity level.
  //   LogToStderr()  - directs all log messages to stderr.
  //   FlushInfoLog() - flushes informational log messages.
  //
  // Stdout and stderr capturing:
  //   CaptureStdout()     - starts capturing stdout.
  //   GetCapturedStdout() - stops capturing stdout and returns the captured
  //                         string.
  //   CaptureStderr()     - starts capturing stderr.
  //   GetCapturedStderr() - stops capturing stderr and returns the captured
  //                         string.
  //
  // Integer types:
  //   TypeWithSize   - maps an integer to a int type.
  //   Int32, UInt32, Int64, UInt64, TimeInMillis
  //                  - integers of known sizes.
  //   BiggestInt     - the biggest signed integer type.
  //
  // Command-line utilities:
  //   GTEST_FLAG()       - references a flag.
  //   GTEST_DECLARE_*()  - declares a flag.
  //   GTEST_DEFINE_*()   - defines a flag.
  //   GetInjectableArgvs() - returns the command line as a vector of strings.
  //
  // Environment variable utilities:
  //   GetEnv()             - gets the value of an environment variable.
  //   BoolFromGTestEnv()   - parses a bool environment variable.
  //   Int32FromGTestEnv()  - parses an Int32 environment variable.
  //   StringFromGTestEnv() - parses a string environment variable.
  
  #include <ctype.h>   // for isspace, etc
  #include <stddef.h>  // for ptrdiff_t
  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
  #ifndef _WIN32_WCE
  # include <sys/types.h>
  # include <sys/stat.h>
  #endif  // !_WIN32_WCE
  
  #if defined __APPLE__
  # include <AvailabilityMacros.h>
  # include <TargetConditionals.h>
  #endif
  
  #include <iostream>  // NOLINT
  #include <sstream>  // NOLINT
  #include <string>  // NOLINT
  
  #define GTEST_DEV_EMAIL_ "googletestframework@@googlegroups.com"
  #define GTEST_FLAG_PREFIX_ "gtest_"
  #define GTEST_FLAG_PREFIX_DASH_ "gtest-"
  #define GTEST_FLAG_PREFIX_UPPER_ "GTEST_"
  #define GTEST_NAME_ "Google Test"
  #define GTEST_PROJECT_URL_ "http://code.google.com/p/googletest/"
  
  // Determines the version of gcc that is used to compile this.
  #ifdef __GNUC__
  // 40302 means version 4.3.2.
  # define GTEST_GCC_VER_ \
      (__GNUC__*10000 + __GNUC_MINOR__*100 + __GNUC_PATCHLEVEL__)
  #endif  // __GNUC__
  
  // Determines the platform on which Google Test is compiled.
  #ifdef __CYGWIN__
  # define GTEST_OS_CYGWIN 1
  #elif defined __SYMBIAN32__
  # define GTEST_OS_SYMBIAN 1
  #elif defined _WIN32
  # define GTEST_OS_WINDOWS 1
  # ifdef _WIN32_WCE
  #  define GTEST_OS_WINDOWS_MOBILE 1
  # elif defined(__MINGW__) || defined(__MINGW32__)
  #  define GTEST_OS_WINDOWS_MINGW 1
  # else
  #  define GTEST_OS_WINDOWS_DESKTOP 1
  # endif  // _WIN32_WCE
  #elif defined __APPLE__
  # define GTEST_OS_MAC 1
  # if TARGET_OS_IPHONE
  #  define GTEST_OS_IOS 1
  #  if TARGET_IPHONE_SIMULATOR
  #   define GTEST_OS_IOS_SIMULATOR 1
  #  endif
  # endif
  #elif defined __linux__
  # define GTEST_OS_LINUX 1
  # if defined __ANDROID__
  #  define GTEST_OS_LINUX_ANDROID 1
  # endif
  #elif defined __MVS__
  # define GTEST_OS_ZOS 1
  #elif defined(__sun) && defined(__SVR4)
  # define GTEST_OS_SOLARIS 1
  #elif defined(_AIX)
  # define GTEST_OS_AIX 1
  #elif defined(__hpux)
  # define GTEST_OS_HPUX 1
  #elif defined __native_client__
  # define GTEST_OS_NACL 1
  #elif defined __OpenBSD__
  # define GTEST_OS_OPENBSD 1
  #elif defined __QNX__
  # define GTEST_OS_QNX 1
  #endif  // __CYGWIN__
  
  #ifndef GTEST_LANG_CXX11
  // gcc and clang define __GXX_EXPERIMENTAL_CXX0X__ when
  // -std={c,gnu}++{0x,11} is passed.  The C++11 standard specifies a
  // value for __cplusplus, and recent versions of clang, gcc, and
  // probably other compilers set that too in C++11 mode.
  # if __GXX_EXPERIMENTAL_CXX0X__ || __cplusplus >= 201103L
  // Compiling in at least C++11 mode.
  #  define GTEST_LANG_CXX11 1
  # else
  #  define GTEST_LANG_CXX11 0
  # endif
  #endif
  
  // Brings in definitions for functions used in the testing::internal::posix
  // namespace (read, write, close, chdir, isatty, stat). We do not currently
  // use them on Windows Mobile.
  #if !GTEST_OS_WINDOWS
  // This assumes that non-Windows OSes provide unistd.h. For OSes where this
  // is not the case, we need to include headers that provide the functions
  // mentioned above.
  # include <unistd.h>
  # include <strings.h>
  #elif !GTEST_OS_WINDOWS_MOBILE
  # include <direct.h>
  # include <io.h>
  #endif
  
  #if GTEST_OS_LINUX_ANDROID
  // Used to define __ANDROID_API__ matching the target NDK API level.
  #  include <android/api-level.h>  // NOLINT
  #endif
  
  // Defines this to true iff Google Test can use POSIX regular expressions.
  #ifndef GTEST_HAS_POSIX_RE
  # if GTEST_OS_LINUX_ANDROID
  // On Android, <regex.h> is only available starting with Gingerbread.
  #  define GTEST_HAS_POSIX_RE (__ANDROID_API__ >= 9)
  # else
  #  define GTEST_HAS_POSIX_RE (!GTEST_OS_WINDOWS)
  # endif
  #endif
  
  #if GTEST_HAS_POSIX_RE
  
  // On some platforms, <regex.h> needs someone to define size_t, and
  // won't compile otherwise.  We can #include it here as we already
  // included <stdlib.h>, which is guaranteed to define size_t through
  // <stddef.h>.
  # include <regex.h>  // NOLINT
  
  # define GTEST_USES_POSIX_RE 1
  
  #elif GTEST_OS_WINDOWS
  
  // <regex.h> is not available on Windows.  Use our own simple regex
  // implementation instead.
  # define GTEST_USES_SIMPLE_RE 1
  
  #else
  
  // <regex.h> may not be available on this platform.  Use our own
  // simple regex implementation instead.
  # define GTEST_USES_SIMPLE_RE 1
  
  #endif  // GTEST_HAS_POSIX_RE
  
  #ifndef GTEST_HAS_EXCEPTIONS
  // The user didn't tell us whether exceptions are enabled, so we need
  // to figure it out.
  # if defined(_MSC_VER) || defined(__BORLANDC__)
  // MSVC's and C++Builder's implementations of the STL use the _HAS_EXCEPTIONS
  // macro to enable exceptions, so we'll do the same.
  // Assumes that exceptions are enabled by default.
  #  ifndef _HAS_EXCEPTIONS
  #   define _HAS_EXCEPTIONS 1
  #  endif  // _HAS_EXCEPTIONS
  #  define GTEST_HAS_EXCEPTIONS _HAS_EXCEPTIONS
  # elif defined(__GNUC__) && __EXCEPTIONS
  // gcc defines __EXCEPTIONS to 1 iff exceptions are enabled.
  #  define GTEST_HAS_EXCEPTIONS 1
  # elif defined(__SUNPRO_CC)
  // Sun Pro CC supports exceptions.  However, there is no compile-time way of
  // detecting whether they are enabled or not.  Therefore, we assume that
  // they are enabled unless the user tells us otherwise.
  #  define GTEST_HAS_EXCEPTIONS 1
  # elif defined(__IBMCPP__) && __EXCEPTIONS
  // xlC defines __EXCEPTIONS to 1 iff exceptions are enabled.
  #  define GTEST_HAS_EXCEPTIONS 1
  # elif defined(__HP_aCC)
  // Exception handling is in effect by default in HP aCC compiler. It has to
  // be turned of by +noeh compiler option if desired.
  #  define GTEST_HAS_EXCEPTIONS 1
  # else
  // For other compilers, we assume exceptions are disabled to be
  // conservative.
  #  define GTEST_HAS_EXCEPTIONS 0
  # endif  // defined(_MSC_VER) || defined(__BORLANDC__)
  #endif  // GTEST_HAS_EXCEPTIONS
  
  #if !defined(GTEST_HAS_STD_STRING)
  // Even though we don't use this macro any longer, we keep it in case
  // some clients still depend on it.
  # define GTEST_HAS_STD_STRING 1
  #elif !GTEST_HAS_STD_STRING
  // The user told us that ::std::string isn't available.
  # error "Google Test cannot be used where ::std::string isn't available."
  #endif  // !defined(GTEST_HAS_STD_STRING)
  
  #ifndef GTEST_HAS_GLOBAL_STRING
  // The user didn't tell us whether ::string is available, so we need
  // to figure it out.
  
  # define GTEST_HAS_GLOBAL_STRING 0
  
  #endif  // GTEST_HAS_GLOBAL_STRING
  
  #ifndef GTEST_HAS_STD_WSTRING
  // The user didn't tell us whether ::std::wstring is available, so we need
  // to figure it out.
  // TODO(wan@google.com): uses autoconf to detect whether ::std::wstring
  //   is available.
  
  // Cygwin 1.7 and below doesn't support ::std::wstring.
  // Solaris' libc++ doesn't support it either.  Android has
  // no support for it at least as recent as Froyo (2.2).
  # define GTEST_HAS_STD_WSTRING \
      (!(GTEST_OS_LINUX_ANDROID || GTEST_OS_CYGWIN || GTEST_OS_SOLARIS))
  
  #endif  // GTEST_HAS_STD_WSTRING
  
  #ifndef GTEST_HAS_GLOBAL_WSTRING
  // The user didn't tell us whether ::wstring is available, so we need
  // to figure it out.
  # define GTEST_HAS_GLOBAL_WSTRING \
      (GTEST_HAS_STD_WSTRING && GTEST_HAS_GLOBAL_STRING)
  #endif  // GTEST_HAS_GLOBAL_WSTRING
  
  // Determines whether RTTI is available.
  #ifndef GTEST_HAS_RTTI
  // The user didn't tell us whether RTTI is enabled, so we need to
  // figure it out.
  
  # ifdef _MSC_VER
  
  #  ifdef _CPPRTTI  // MSVC defines this macro iff RTTI is enabled.
  #   define GTEST_HAS_RTTI 1
  #  else
  #   define GTEST_HAS_RTTI 0
  #  endif
  
  // Starting with version 4.3.2, gcc defines __GXX_RTTI iff RTTI is enabled.
  # elif defined(__GNUC__) && (GTEST_GCC_VER_ >= 40302)
  
  #  ifdef __GXX_RTTI
  // When building against STLport with the Android NDK and with
  // -frtti -fno-exceptions, the build fails at link time with undefined
  // references to __cxa_bad_typeid. Note sure if STL or toolchain bug,
  // so disable RTTI when detected.
  #   if GTEST_OS_LINUX_ANDROID && defined(_STLPORT_MAJOR) && \
         !defined(__EXCEPTIONS)
  #    define GTEST_HAS_RTTI 0
  #   else
  #    define GTEST_HAS_RTTI 1
  #   endif  // GTEST_OS_LINUX_ANDROID && __STLPORT_MAJOR && !__EXCEPTIONS
  #  else
  #   define GTEST_HAS_RTTI 0
  #  endif  // __GXX_RTTI
  
  // Clang defines __GXX_RTTI starting with version 3.0, but its manual recommends
  // using has_feature instead. has_feature(cxx_rtti) is supported since 2.7, the
  // first version with C++ support.
  # elif defined(__clang__)
  
  #  define GTEST_HAS_RTTI __has_feature(cxx_rtti)
  
  // Starting with version 9.0 IBM Visual Age defines __RTTI_ALL__ to 1 if
  // both the typeid and dynamic_cast features are present.
  # elif defined(__IBMCPP__) && (__IBMCPP__ >= 900)
  
  #  ifdef __RTTI_ALL__
  #   define GTEST_HAS_RTTI 1
  #  else
  #   define GTEST_HAS_RTTI 0
  #  endif
  
  # else
  
  // For all other compilers, we assume RTTI is enabled.
  #  define GTEST_HAS_RTTI 1
  
  # endif  // _MSC_VER
  
  #endif  // GTEST_HAS_RTTI
  
  // It's this header's responsibility to #include <typeinfo> when RTTI
  // is enabled.
  #if GTEST_HAS_RTTI
  # include <typeinfo>
  #endif
  
  // Determines whether Google Test can use the pthreads library.
  #ifndef GTEST_HAS_PTHREAD
  // The user didn't tell us explicitly, so we assume pthreads support is
  // available on Linux and Mac.
  //
  // To disable threading support in Google Test, add -DGTEST_HAS_PTHREAD=0
  // to your compiler flags.
  # define GTEST_HAS_PTHREAD (GTEST_OS_LINUX || GTEST_OS_MAC || GTEST_OS_HPUX \
      || GTEST_OS_QNX)
  #endif  // GTEST_HAS_PTHREAD
  
  #if GTEST_HAS_PTHREAD
  // gtest-port.h guarantees to #include <pthread.h> when GTEST_HAS_PTHREAD is
  // true.
  # include <pthread.h>  // NOLINT
  
  // For timespec and nanosleep, used below.
  # include <time.h>  // NOLINT
  #endif
  
  // Determines whether Google Test can use tr1/tuple.  You can define
  // this macro to 0 to prevent Google Test from using tuple (any
  // feature depending on tuple with be disabled in this mode).
  #ifndef GTEST_HAS_TR1_TUPLE
  # if GTEST_OS_LINUX_ANDROID && defined(_STLPORT_MAJOR)
  // STLport, provided with the Android NDK, has neither <tr1/tuple> or <tuple>.
  #  define GTEST_HAS_TR1_TUPLE 0
  # else
  // The user didn't tell us not to do it, so we assume it's OK.
  #  define GTEST_HAS_TR1_TUPLE 1
  # endif
  #endif  // GTEST_HAS_TR1_TUPLE
  
  // Determines whether Google Test's own tr1 tuple implementation
  // should be used.
  #ifndef GTEST_USE_OWN_TR1_TUPLE
  // The user didn't tell us, so we need to figure it out.
  
  // We use our own TR1 tuple if we aren't sure the user has an
  // implementation of it already.  At this time, libstdc++ 4.0.0+ and
  // MSVC 2010 are the only mainstream standard libraries that come
  // with a TR1 tuple implementation.  NVIDIA's CUDA NVCC compiler
  // pretends to be GCC by defining __GNUC__ and friends, but cannot
  // compile GCC's tuple implementation.  MSVC 2008 (9.0) provides TR1
  // tuple in a 323 MB Feature Pack download, which we cannot assume the
  // user has.  QNX's QCC compiler is a modified GCC but it doesn't
  // support TR1 tuple.  libc++ only provides std::tuple, in C++11 mode,
  // and it can be used with some compilers that define __GNUC__.
  # if (defined(__GNUC__) && !defined(__CUDACC__) && (GTEST_GCC_VER_ >= 40000) \
        && !GTEST_OS_QNX && !defined(_LIBCPP_VERSION)) || _MSC_VER >= 1600
  #  define GTEST_ENV_HAS_TR1_TUPLE_ 1
  # endif
  
  // C++11 specifies that <tuple> provides std::tuple. Use that if gtest is used
  // in C++11 mode and libstdc++ isn't very old (binaries targeting OS X 10.6
  // can build with clang but need to use gcc4.2's libstdc++).
  # if GTEST_LANG_CXX11 && (!defined(__GLIBCXX__) || __GLIBCXX__ > 20110325)
  #  define GTEST_ENV_HAS_STD_TUPLE_ 1
  # endif
  
  # if GTEST_ENV_HAS_TR1_TUPLE_ || GTEST_ENV_HAS_STD_TUPLE_
  #  define GTEST_USE_OWN_TR1_TUPLE 0
  # else
  #  define GTEST_USE_OWN_TR1_TUPLE 1
  # endif
  
  #endif  // GTEST_USE_OWN_TR1_TUPLE
  
  // To avoid conditional compilation everywhere, we make it
  // gtest-port.h's responsibility to #include the header implementing
  // tr1/tuple.
  #if GTEST_HAS_TR1_TUPLE
  
  # if GTEST_USE_OWN_TR1_TUPLE
  #  include "gtest/internal/gtest-tuple.h"
  # elif GTEST_ENV_HAS_STD_TUPLE_
  #  include <tuple>
  // C++11 puts its tuple into the ::std namespace rather than
  // ::std::tr1.  gtest expects tuple to live in ::std::tr1, so put it there.
  // This causes undefined behavior, but supported compilers react in
  // the way we intend.
  namespace std {
  namespace tr1 {
  using ::std::get;
  using ::std::make_tuple;
  using ::std::tuple;
  using ::std::tuple_element;
  using ::std::tuple_size;
  }
  }
  
  # elif GTEST_OS_SYMBIAN
  
  // On Symbian, BOOST_HAS_TR1_TUPLE causes Boost's TR1 tuple library to
  // use STLport's tuple implementation, which unfortunately doesn't
  // work as the copy of STLport distributed with Symbian is incomplete.
  // By making sure BOOST_HAS_TR1_TUPLE is undefined, we force Boost to
  // use its own tuple implementation.
  #  ifdef BOOST_HAS_TR1_TUPLE
  #   undef BOOST_HAS_TR1_TUPLE
  #  endif  // BOOST_HAS_TR1_TUPLE
  
  // This prevents <boost/tr1/detail/config.hpp>, which defines
  // BOOST_HAS_TR1_TUPLE, from being #included by Boost's <tuple>.
  #  define BOOST_TR1_DETAIL_CONFIG_HPP_INCLUDED
  #  include <tuple>
  
  # elif defined(__GNUC__) && (GTEST_GCC_VER_ >= 40000)
  // GCC 4.0+ implements tr1/tuple in the <tr1/tuple> header.  This does
  // not conform to the TR1 spec, which requires the header to be <tuple>.
  
  #  if !GTEST_HAS_RTTI && GTEST_GCC_VER_ < 40302
  // Until version 4.3.2, gcc has a bug that causes <tr1/functional>,
  // which is #included by <tr1/tuple>, to not compile when RTTI is
  // disabled.  _TR1_FUNCTIONAL is the header guard for
  // <tr1/functional>.  Hence the following #define is a hack to prevent
  // <tr1/functional> from being included.
  #   define _TR1_FUNCTIONAL 1
  #   include <tr1/tuple>
  #   undef _TR1_FUNCTIONAL  // Allows the user to #include
                          // <tr1/functional> if he chooses to.
  #  else
  #   include <tr1/tuple>  // NOLINT
  #  endif  // !GTEST_HAS_RTTI && GTEST_GCC_VER_ < 40302
  
  # else
  // If the compiler is not GCC 4.0+, we assume the user is using a
  // spec-conforming TR1 implementation.
  #  include <tuple>  // NOLINT
  # endif  // GTEST_USE_OWN_TR1_TUPLE
  
  #endif  // GTEST_HAS_TR1_TUPLE
  
  // Determines whether clone(2) is supported.
  // Usually it will only be available on Linux, excluding
  // Linux on the Itanium architecture.
  // Also see http://linux.die.net/man/2/clone.
  #ifndef GTEST_HAS_CLONE
  // The user didn't tell us, so we need to figure it out.
  
  # if GTEST_OS_LINUX && !defined(__ia64__)
  #  if GTEST_OS_LINUX_ANDROID
  // On Android, clone() is only available on ARM starting with Gingerbread.
  #    if defined(__arm__) && __ANDROID_API__ >= 9
  #     define GTEST_HAS_CLONE 1
  #    else
  #     define GTEST_HAS_CLONE 0
  #    endif
  #  else
  #   define GTEST_HAS_CLONE 1
  #  endif
  # else
  #  define GTEST_HAS_CLONE 0
  # endif  // GTEST_OS_LINUX && !defined(__ia64__)
  
  #endif  // GTEST_HAS_CLONE
  
  // Determines whether to support stream redirection. This is used to test
  // output correctness and to implement death tests.
  #ifndef GTEST_HAS_STREAM_REDIRECTION
  // By default, we assume that stream redirection is supported on all
  // platforms except known mobile ones.
  # if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_SYMBIAN
  #  define GTEST_HAS_STREAM_REDIRECTION 0
  # else
  #  define GTEST_HAS_STREAM_REDIRECTION 1
  # endif  // !GTEST_OS_WINDOWS_MOBILE && !GTEST_OS_SYMBIAN
  #endif  // GTEST_HAS_STREAM_REDIRECTION
  
  // Determines whether to support death tests.
  // Google Test does not support death tests for VC 7.1 and earlier as
  // abort() in a VC 7.1 application compiled as GUI in debug config
  // pops up a dialog window that cannot be suppressed programmatically.
  #if (GTEST_OS_LINUX || GTEST_OS_CYGWIN || GTEST_OS_SOLARIS || \
       (GTEST_OS_MAC && !GTEST_OS_IOS) || GTEST_OS_IOS_SIMULATOR || \
       (GTEST_OS_WINDOWS_DESKTOP && _MSC_VER >= 1400) || \
       GTEST_OS_WINDOWS_MINGW || GTEST_OS_AIX || GTEST_OS_HPUX || \
       GTEST_OS_OPENBSD || GTEST_OS_QNX)
  # define GTEST_HAS_DEATH_TEST 1
  # include <vector>  // NOLINT
  #endif
  
  // We don't support MSVC 7.1 with exceptions disabled now.  Therefore
  // all the compilers we care about are adequate for supporting
  // value-parameterized tests.
  #define GTEST_HAS_PARAM_TEST 1
  
  // Determines whether to support type-driven tests.
  
  // Typed tests need <typeinfo> and variadic macros, which GCC, VC++ 8.0,
  // Sun Pro CC, IBM Visual Age, and HP aCC support.
  #if defined(__GNUC__) || (_MSC_VER >= 1400) || defined(__SUNPRO_CC) || \
      defined(__IBMCPP__) || defined(__HP_aCC)
  # define GTEST_HAS_TYPED_TEST 1
  # define GTEST_HAS_TYPED_TEST_P 1
  #endif
  
  // Determines whether to support Combine(). This only makes sense when
  // value-parameterized tests are enabled.  The implementation doesn't
  // work on Sun Studio since it doesn't understand templated conversion
  // operators.
  #if GTEST_HAS_PARAM_TEST && GTEST_HAS_TR1_TUPLE && !defined(__SUNPRO_CC)
  # define GTEST_HAS_COMBINE 1
  #endif
  
  // Determines whether the system compiler uses UTF-16 for encoding wide strings.
  #define GTEST_WIDE_STRING_USES_UTF16_ \
      (GTEST_OS_WINDOWS || GTEST_OS_CYGWIN || GTEST_OS_SYMBIAN || GTEST_OS_AIX)
  
  // Determines whether test results can be streamed to a socket.
  #if GTEST_OS_LINUX
  # define GTEST_CAN_STREAM_RESULTS_ 1
  #endif
  
  // Defines some utility macros.
  
  // The GNU compiler emits a warning if nested "if" statements are followed by
  // an "else" statement and braces are not used to explicitly disambiguate the
  // "else" binding.  This leads to problems with code like:
  //
  //   if (gate)
  //     ASSERT_*(condition) << "Some message";
  //
  // The "switch (0) case 0:" idiom is used to suppress this.
  #ifdef __INTEL_COMPILER
  # define GTEST_AMBIGUOUS_ELSE_BLOCKER_
  #else
  # define GTEST_AMBIGUOUS_ELSE_BLOCKER_ switch (0) case 0: default:  // NOLINT
  #endif
  
  // Use this annotation at the end of a struct/class definition to
  // prevent the compiler from optimizing away instances that are never
  // used.  This is useful when all interesting logic happens inside the
  // c'tor and / or d'tor.  Example:
  //
  //   struct Foo {
  //     Foo() { ... }
  //   } GTEST_ATTRIBUTE_UNUSED_;
  //
  // Also use it after a variable or parameter declaration to tell the
  // compiler the variable/parameter does not have to be used.
  #if defined(__GNUC__) && !defined(COMPILER_ICC)
  # define GTEST_ATTRIBUTE_UNUSED_ __attribute__ ((unused))
  #else
  # define GTEST_ATTRIBUTE_UNUSED_
  #endif
  
  // A macro to disallow operator=
  // This should be used in the private: declarations for a class.
  #define GTEST_DISALLOW_ASSIGN_(type)\
    void operator=(type const &)
  
  // A macro to disallow copy constructor and operator=
  // This should be used in the private: declarations for a class.
  #define GTEST_DISALLOW_COPY_AND_ASSIGN_(type)\
    type(type const &);\
    GTEST_DISALLOW_ASSIGN_(type)
  
  // 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() GTEST_MUST_USE_RESULT_;
  #if defined(__GNUC__) && (GTEST_GCC_VER_ >= 30400) && !defined(COMPILER_ICC)
  # define GTEST_MUST_USE_RESULT_ __attribute__ ((warn_unused_result))
  #else
  # define GTEST_MUST_USE_RESULT_
  #endif  // __GNUC__ && (GTEST_GCC_VER_ >= 30400) && !COMPILER_ICC
  
  // Determine whether the compiler supports Microsoft's Structured Exception
  // Handling.  This is supported by several Windows compilers but generally
  // does not exist on any other system.
  #ifndef GTEST_HAS_SEH
  // The user didn't tell us, so we need to figure it out.
  
  # if defined(_MSC_VER) || defined(__BORLANDC__)
  // These two compilers are known to support SEH.
  #  define GTEST_HAS_SEH 1
  # else
  // Assume no SEH.
  #  define GTEST_HAS_SEH 0
  # endif
  
  #endif  // GTEST_HAS_SEH
  
  #ifdef _MSC_VER
  
  # if GTEST_LINKED_AS_SHARED_LIBRARY
  #  define GTEST_API_ __declspec(dllimport)
  # elif GTEST_CREATE_SHARED_LIBRARY
  #  define GTEST_API_ __declspec(dllexport)
  # endif
  
  #endif  // _MSC_VER
  
  #ifndef GTEST_API_
  # define GTEST_API_
  #endif
  
  #ifdef __GNUC__
  // Ask the compiler to never inline a given function.
  # define GTEST_NO_INLINE_ __attribute__((noinline))
  #else
  # define GTEST_NO_INLINE_
  #endif
  
  // _LIBCPP_VERSION is defined by the libc++ library from the LLVM project.
  #if defined(__GLIBCXX__) || defined(_LIBCPP_VERSION)
  # define GTEST_HAS_CXXABI_H_ 1
  #else
  # define GTEST_HAS_CXXABI_H_ 0
  #endif
  
  namespace testing {
  
  class Message;
  
  namespace internal {
  
  // A secret type that Google Test users don't know about.  It has no
  // definition on purpose.  Therefore it's impossible to create a
  // Secret object, which is what we want.
  class Secret;
  
  // The GTEST_COMPILE_ASSERT_ macro can be used to verify that a compile time
  // expression is true. For example, you could use it to verify the
  // size of a static array:
  //
  //   GTEST_COMPILE_ASSERT_(ARRAYSIZE(content_type_names) == CONTENT_NUM_TYPES,
  //                         content_type_names_incorrect_size);
  //
  // or to make sure a struct is smaller than a certain size:
  //
  //   GTEST_COMPILE_ASSERT_(sizeof(foo) < 128, foo_too_large);
  //
  // The second argument to the macro is the name of the variable. If
  // the expression is false, most compilers will issue a warning/error
  // containing the name of the variable.
  
  template <bool>
  struct CompileAssert {
  };
  
  #define GTEST_COMPILE_ASSERT_(expr, msg) \
    typedef ::testing::internal::CompileAssert<(static_cast<bool>(expr))> \
        msg[static_cast<bool>(expr) ? 1 : -1] GTEST_ATTRIBUTE_UNUSED_
  
  // Implementation details of GTEST_COMPILE_ASSERT_:
  //
  // - GTEST_COMPILE_ASSERT_ works by defining an array type that has -1
  //   elements (and thus is invalid) when the expression is false.
  //
  // - The simpler definition
  //
  //    #define GTEST_COMPILE_ASSERT_(expr, msg) typedef char msg[(expr) ? 1 : -1]
  //
  //   does not work, as gcc supports variable-length arrays whose sizes
  //   are determined at run-time (this is gcc's extension and not part
  //   of the C++ standard).  As a result, gcc fails to reject the
  //   following code with the simple definition:
  //
  //     int foo;
  //     GTEST_COMPILE_ASSERT_(foo, msg); // not supposed to compile as foo is
  //                                      // not a compile-time constant.
  //
  // - By using the type CompileAssert<(bool(expr))>, we ensures that
  //   expr is a compile-time constant.  (Template arguments must be
  //   determined at compile-time.)
  //
  // - The outter parentheses in CompileAssert<(bool(expr))> are necessary
  //   to work around a bug in gcc 3.4.4 and 4.0.1.  If we had written
  //
  //     CompileAssert<bool(expr)>
  //
  //   instead, these compilers will refuse to compile
  //
  //     GTEST_COMPILE_ASSERT_(5 > 0, some_message);
  //
  //   (They seem to think the ">" in "5 > 0" marks the end of the
  //   template argument list.)
  //
  // - The array size is (bool(expr) ? 1 : -1), instead of simply
  //
  //     ((expr) ? 1 : -1).
  //
  //   This is to avoid running into a bug in MS VC 7.1, which
  //   causes ((0.0) ? 1 : -1) to incorrectly evaluate to 1.
  
  // StaticAssertTypeEqHelper is used by StaticAssertTypeEq defined in gtest.h.
  //
  // This template is declared, but intentionally undefined.
  template <typename T1, typename T2>
  struct StaticAssertTypeEqHelper;
  
  template <typename T>
  struct StaticAssertTypeEqHelper<T, T> {};
  
  #if GTEST_HAS_GLOBAL_STRING
  typedef ::string string;
  #else
  typedef ::std::string string;
  #endif  // GTEST_HAS_GLOBAL_STRING
  
  #if GTEST_HAS_GLOBAL_WSTRING
  typedef ::wstring wstring;
  #elif GTEST_HAS_STD_WSTRING
  typedef ::std::wstring wstring;
  #endif  // GTEST_HAS_GLOBAL_WSTRING
  
  // A helper for suppressing warnings on constant condition.  It just
  // returns 'condition'.
  GTEST_API_ bool IsTrue(bool condition);
  
  // Defines scoped_ptr.
  
  // This implementation of scoped_ptr is PARTIAL - it only contains
  // enough stuff to satisfy Google Test's need.
  template <typename T>
  class scoped_ptr {
   public:
    typedef T element_type;
  
    explicit scoped_ptr(T* p = NULL) : ptr_(p) {}
    ~scoped_ptr() { reset(); }
  
    T& operator*() const { return *ptr_; }
    T* operator->() const { return ptr_; }
    T* get() const { return ptr_; }
  
    T* release() {
      T* const ptr = ptr_;
      ptr_ = NULL;
      return ptr;
    }
  
    void reset(T* p = NULL) {
      if (p != ptr_) {
        if (IsTrue(sizeof(T) > 0)) {  // Makes sure T is a complete type.
          delete ptr_;
        }
        ptr_ = p;
      }
    }
  
   private:
    T* ptr_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(scoped_ptr);
  };
  
  // Defines RE.
  
  // A simple C++ wrapper for <regex.h>.  It uses the POSIX Extended
  // Regular Expression syntax.
  class GTEST_API_ RE {
   public:
    // A copy constructor is required by the Standard to initialize object
    // references from r-values.
    RE(const RE& other) { Init(other.pattern()); }
  
    // Constructs an RE from a string.
    RE(const ::std::string& regex) { Init(regex.c_str()); }  // NOLINT
  
  #if GTEST_HAS_GLOBAL_STRING
  
    RE(const ::string& regex) { Init(regex.c_str()); }  // NOLINT
  
  #endif  // GTEST_HAS_GLOBAL_STRING
  
    RE(const char* regex) { Init(regex); }  // NOLINT
    ~RE();
  
    // Returns the string representation of the regex.
    const char* pattern() const { return pattern_; }
  
    // FullMatch(str, re) returns true iff regular expression re matches
    // the entire str.
    // PartialMatch(str, re) returns true iff regular expression re
    // matches a substring of str (including str itself).
    //
    // TODO(wan@google.com): make FullMatch() and PartialMatch() work
    // when str contains NUL characters.
    static bool FullMatch(const ::std::string& str, const RE& re) {
      return FullMatch(str.c_str(), re);
    }
    static bool PartialMatch(const ::std::string& str, const RE& re) {
      return PartialMatch(str.c_str(), re);
    }
  
  #if GTEST_HAS_GLOBAL_STRING
  
    static bool FullMatch(const ::string& str, const RE& re) {
      return FullMatch(str.c_str(), re);
    }
    static bool PartialMatch(const ::string& str, const RE& re) {
      return PartialMatch(str.c_str(), re);
    }
  
  #endif  // GTEST_HAS_GLOBAL_STRING
  
    static bool FullMatch(const char* str, const RE& re);
    static bool PartialMatch(const char* str, const RE& re);
  
   private:
    void Init(const char* regex);
  
    // We use a const char* instead of an std::string, as Google Test used to be
    // used where std::string is not available.  TODO(wan@google.com): change to
    // std::string.
    const char* pattern_;
    bool is_valid_;
  
  #if GTEST_USES_POSIX_RE
  
    regex_t full_regex_;     // For FullMatch().
    regex_t partial_regex_;  // For PartialMatch().
  
  #else  // GTEST_USES_SIMPLE_RE
  
    const char* full_pattern_;  // For FullMatch();
  
  #endif
  
    GTEST_DISALLOW_ASSIGN_(RE);
  };
  
  // Formats a source file path and a line number as they would appear
  // in an error message from the compiler used to compile this code.
  GTEST_API_ ::std::string FormatFileLocation(const char* file, int line);
  
  // Formats a file location for compiler-independent XML output.
  // Although this function is not platform dependent, we put it next to
  // FormatFileLocation in order to contrast the two functions.
  GTEST_API_ ::std::string FormatCompilerIndependentFileLocation(const char* file,
                                                                 int line);
  
  // Defines logging utilities:
  //   GTEST_LOG_(severity) - logs messages at the specified severity level. The
  //                          message itself is streamed into the macro.
  //   LogToStderr()  - directs all log messages to stderr.
  //   FlushInfoLog() - flushes informational log messages.
  
  enum GTestLogSeverity {
    GTEST_INFO,
    GTEST_WARNING,
    GTEST_ERROR,
    GTEST_FATAL
  };
  
  // Formats log entry severity, provides a stream object for streaming the
  // log message, and terminates the message with a newline when going out of
  // scope.
  class GTEST_API_ GTestLog {
   public:
    GTestLog(GTestLogSeverity severity, const char* file, int line);
  
    // Flushes the buffers and, if severity is GTEST_FATAL, aborts the program.
    ~GTestLog();
  
    ::std::ostream& GetStream() { return ::std::cerr; }
  
   private:
    const GTestLogSeverity severity_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(GTestLog);
  };
  
  #define GTEST_LOG_(severity) \
      ::testing::internal::GTestLog(::testing::internal::GTEST_##severity, \
                                    __FILE__, __LINE__).GetStream()
  
  inline void LogToStderr() {}
  inline void FlushInfoLog() { fflush(NULL); }
  
  // INTERNAL IMPLEMENTATION - DO NOT USE.
  //
  // GTEST_CHECK_ is an all-mode assert. It aborts the program if the condition
  // is not satisfied.
  //  Synopsys:
  //    GTEST_CHECK_(boolean_condition);
  //     or
  //    GTEST_CHECK_(boolean_condition) << "Additional message";
  //
  //    This checks the condition and if the condition is not satisfied
  //    it prints message about the condition violation, including the
  //    condition itself, plus additional message streamed into it, if any,
  //    and then it aborts the program. It aborts the program irrespective of
  //    whether it is built in the debug mode or not.
  #define GTEST_CHECK_(condition) \
      GTEST_AMBIGUOUS_ELSE_BLOCKER_ \
      if (::testing::internal::IsTrue(condition)) \
        ; \
      else \
        GTEST_LOG_(FATAL) << "Condition " #condition " failed. "
  
  // An all-mode assert to verify that the given POSIX-style function
  // call returns 0 (indicating success).  Known limitation: this
  // doesn't expand to a balanced 'if' statement, so enclose the macro
  // in {} if you need to use it as the only statement in an 'if'
  // branch.
  #define GTEST_CHECK_POSIX_SUCCESS_(posix_call) \
    if (const int gtest_error = (posix_call)) \
      GTEST_LOG_(FATAL) << #posix_call << "failed with error " \
                        << gtest_error
  
  // INTERNAL IMPLEMENTATION - DO NOT USE IN USER CODE.
  //
  // Use ImplicitCast_ as a safe version of static_cast for upcasting in
  // the type hierarchy (e.g. casting a Foo* to a SuperclassOfFoo* or a
  // const Foo*).  When you use ImplicitCast_, the compiler checks that
  // the cast is safe.  Such explicit ImplicitCast_s are necessary in
  // surprisingly many situations where C++ demands an exact type match
  // instead of an argument type convertable to a target type.
  //
  // The syntax for using ImplicitCast_ is the same as for static_cast:
  //
  //   ImplicitCast_<ToType>(expr)
  //
  // ImplicitCast_ would have been part of the C++ standard library,
  // but the proposal was submitted too late.  It will probably make
  // its way into the language in the future.
  //
  // This relatively ugly name is intentional. It prevents clashes with
  // similar functions users may have (e.g., implicit_cast). The internal
  // namespace alone is not enough because the function can be found by ADL.
  template<typename To>
  inline To ImplicitCast_(To x) { return x; }
  
  // When you upcast (that is, cast a pointer from type Foo to type
  // SuperclassOfFoo), it's fine to use ImplicitCast_<>, since upcasts
  // always succeed.  When you downcast (that is, cast a pointer from
  // type Foo to type SubclassOfFoo), static_cast<> isn't safe, because
  // how do you know the pointer is really of type SubclassOfFoo?  It
  // could be a bare Foo, or of type DifferentSubclassOfFoo.  Thus,
  // when you downcast, you should use this macro.  In debug mode, we
  // use dynamic_cast<> to double-check the downcast is legal (we die
  // if it's not).  In normal mode, we do the efficient static_cast<>
  // instead.  Thus, it's important to test in debug mode to make sure
  // the cast is legal!
  //    This is the only place in the code we should use dynamic_cast<>.
  // In particular, you SHOULDN'T be using dynamic_cast<> in order to
  // do RTTI (eg code like this:
  //    if (dynamic_cast<Subclass1>(foo)) HandleASubclass1Object(foo);
  //    if (dynamic_cast<Subclass2>(foo)) HandleASubclass2Object(foo);
  // You should design the code some other way not to need this.
  //
  // This relatively ugly name is intentional. It prevents clashes with
  // similar functions users may have (e.g., down_cast). The internal
  // namespace alone is not enough because the function can be found by ADL.
  template<typename To, typename From>  // use like this: DownCast_<T*>(foo);
  inline To DownCast_(From* f) {  // so we only accept pointers
    // Ensures that To is a sub-type of From *.  This test is here only
    // for compile-time type checking, and has no overhead in an
    // optimized build at run-time, as it will be optimized away
    // completely.
    if (false) {
      const To to = NULL;
      ::testing::internal::ImplicitCast_<From*>(to);
    }
  
  #if GTEST_HAS_RTTI
    // RTTI: debug mode only!
    GTEST_CHECK_(f == NULL || dynamic_cast<To>(f) != NULL);
  #endif
    return static_cast<To>(f);
  }
  
  // Downcasts the pointer of type Base to Derived.
  // Derived must be a subclass of Base. The parameter MUST
  // point to a class of type Derived, not any subclass of it.
  // When RTTI is available, the function performs a runtime
  // check to enforce this.
  template <class Derived, class Base>
  Derived* CheckedDowncastToActualType(Base* base) {
  #if GTEST_HAS_RTTI
    GTEST_CHECK_(typeid(*base) == typeid(Derived));
    return dynamic_cast<Derived*>(base);  // NOLINT
  #else
    return static_cast<Derived*>(base);  // Poor man's downcast.
  #endif
  }
  
  #if GTEST_HAS_STREAM_REDIRECTION
  
  // Defines the stderr capturer:
  //   CaptureStdout     - starts capturing stdout.
  //   GetCapturedStdout - stops capturing stdout and returns the captured string.
  //   CaptureStderr     - starts capturing stderr.
  //   GetCapturedStderr - stops capturing stderr and returns the captured string.
  //
  GTEST_API_ void CaptureStdout();
  GTEST_API_ std::string GetCapturedStdout();
  GTEST_API_ void CaptureStderr();
  GTEST_API_ std::string GetCapturedStderr();
  
  #endif  // GTEST_HAS_STREAM_REDIRECTION
  
  
  #if GTEST_HAS_DEATH_TEST
  
  const ::std::vector<testing::internal::string>& GetInjectableArgvs();
  void SetInjectableArgvs(const ::std::vector<testing::internal::string>*
                               new_argvs);
  
  // A copy of all command line arguments.  Set by InitGoogleTest().
  extern ::std::vector<testing::internal::string> g_argvs;
  
  #endif  // GTEST_HAS_DEATH_TEST
  
  // Defines synchronization primitives.
  
  #if GTEST_HAS_PTHREAD
  
  // Sleeps for (roughly) n milli-seconds.  This function is only for
  // testing Google Test's own constructs.  Don't use it in user tests,
  // either directly or indirectly.
  inline void SleepMilliseconds(int n) {
    const timespec time = {
      0,                  // 0 seconds.
      n * 1000L * 1000L,  // And n ms.
    };
    nanosleep(&time, NULL);
  }
  
  // Allows a controller thread to pause execution of newly created
  // threads until notified.  Instances of this class must be created
  // and destroyed in the controller thread.
  //
  // This class is only for testing Google Test's own constructs. Do not
  // use it in user tests, either directly or indirectly.
  class Notification {
   public:
    Notification() : notified_(false) {
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_init(&mutex_, NULL));
    }
    ~Notification() {
      pthread_mutex_destroy(&mutex_);
    }
  
    // Notifies all threads created with this notification to start. Must
    // be called from the controller thread.
    void Notify() {
      pthread_mutex_lock(&mutex_);
      notified_ = true;
      pthread_mutex_unlock(&mutex_);
    }
  
    // Blocks until the controller thread notifies. Must be called from a test
    // thread.
    void WaitForNotification() {
      for (;;) {
        pthread_mutex_lock(&mutex_);
        const bool notified = notified_;
        pthread_mutex_unlock(&mutex_);
        if (notified)
          break;
        SleepMilliseconds(10);
      }
    }
  
   private:
    pthread_mutex_t mutex_;
    bool notified_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(Notification);
  };
  
  // As a C-function, ThreadFuncWithCLinkage cannot be templated itself.
  // Consequently, it cannot select a correct instantiation of ThreadWithParam
  // in order to call its Run(). Introducing ThreadWithParamBase as a
  // non-templated base class for ThreadWithParam allows us to bypass this
  // problem.
  class ThreadWithParamBase {
   public:
    virtual ~ThreadWithParamBase() {}
    virtual void Run() = 0;
  };
  
  // pthread_create() accepts a pointer to a function type with the C linkage.
  // According to the Standard (7.5/1), function types with different linkages
  // are different even if they are otherwise identical.  Some compilers (for
  // example, SunStudio) treat them as different types.  Since class methods
  // cannot be defined with C-linkage we need to define a free C-function to
  // pass into pthread_create().
  extern "C" inline void* ThreadFuncWithCLinkage(void* thread) {
    static_cast<ThreadWithParamBase*>(thread)->Run();
    return NULL;
  }
  
  // Helper class for testing Google Test's multi-threading constructs.
  // To use it, write:
  //
  //   void ThreadFunc(int param) { /* Do things with param */ }
  //   Notification thread_can_start;
  //   ...
  //   // The thread_can_start parameter is optional; you can supply NULL.
  //   ThreadWithParam<int> thread(&ThreadFunc, 5, &thread_can_start);
  //   thread_can_start.Notify();
  //
  // These classes are only for testing Google Test's own constructs. Do
  // not use them in user tests, either directly or indirectly.
  template <typename T>
  class ThreadWithParam : public ThreadWithParamBase {
   public:
    typedef void (*UserThreadFunc)(T);
  
    ThreadWithParam(
        UserThreadFunc func, T param, Notification* thread_can_start)
        : func_(func),
          param_(param),
          thread_can_start_(thread_can_start),
          finished_(false) {
      ThreadWithParamBase* const base = this;
      // The thread can be created only after all fields except thread_
      // have been initialized.
      GTEST_CHECK_POSIX_SUCCESS_(
          pthread_create(&thread_, 0, &ThreadFuncWithCLinkage, base));
    }
    ~ThreadWithParam() { Join(); }
  
    void Join() {
      if (!finished_) {
        GTEST_CHECK_POSIX_SUCCESS_(pthread_join(thread_, 0));
        finished_ = true;
      }
    }
  
    virtual void Run() {
      if (thread_can_start_ != NULL)
        thread_can_start_->WaitForNotification();
      func_(param_);
    }
  
   private:
    const UserThreadFunc func_;  // User-supplied thread function.
    const T param_;  // User-supplied parameter to the thread function.
    // When non-NULL, used to block execution until the controller thread
    // notifies.
    Notification* const thread_can_start_;
    bool finished_;  // true iff we know that the thread function has finished.
    pthread_t thread_;  // The native thread object.
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(ThreadWithParam);
  };
  
  // MutexBase and Mutex implement mutex on pthreads-based platforms. They
  // are used in conjunction with class MutexLock:
  //
  //   Mutex mutex;
  //   ...
  //   MutexLock lock(&mutex);  // Acquires the mutex and releases it at the end
  //                            // of the current scope.
  //
  // MutexBase implements behavior for both statically and dynamically
  // allocated mutexes.  Do not use MutexBase directly.  Instead, write
  // the following to define a static mutex:
  //
  //   GTEST_DEFINE_STATIC_MUTEX_(g_some_mutex);
  //
  // You can forward declare a static mutex like this:
  //
  //   GTEST_DECLARE_STATIC_MUTEX_(g_some_mutex);
  //
  // To create a dynamic mutex, just define an object of type Mutex.
  class MutexBase {
   public:
    // Acquires this mutex.
    void Lock() {
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_lock(&mutex_));
      owner_ = pthread_self();
      has_owner_ = true;
    }
  
    // Releases this mutex.
    void Unlock() {
      // Since the lock is being released the owner_ field should no longer be
      // considered valid. We don't protect writing to has_owner_ here, as it's
      // the caller's responsibility to ensure that the current thread holds the
      // mutex when this is called.
      has_owner_ = false;
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_unlock(&mutex_));
    }
  
    // Does nothing if the current thread holds the mutex. Otherwise, crashes
    // with high probability.
    void AssertHeld() const {
      GTEST_CHECK_(has_owner_ && pthread_equal(owner_, pthread_self()))
          << "The current thread is not holding the mutex @" << this;
    }
  
    // A static mutex may be used before main() is entered.  It may even
    // be used before the dynamic initialization stage.  Therefore we
    // must be able to initialize a static mutex object at link time.
    // This means MutexBase has to be a POD and its member variables
    // have to be public.
   public:
    pthread_mutex_t mutex_;  // The underlying pthread mutex.
    // has_owner_ indicates whether the owner_ field below contains a valid thread
    // ID and is therefore safe to inspect (e.g., to use in pthread_equal()). All
    // accesses to the owner_ field should be protected by a check of this field.
    // An alternative might be to memset() owner_ to all zeros, but there's no
    // guarantee that a zero'd pthread_t is necessarily invalid or even different
    // from pthread_self().
    bool has_owner_;
    pthread_t owner_;  // The thread holding the mutex.
  };
  
  // Forward-declares a static mutex.
  # define GTEST_DECLARE_STATIC_MUTEX_(mutex) \
      extern ::testing::internal::MutexBase mutex
  
  // Defines and statically (i.e. at link time) initializes a static mutex.
  // The initialization list here does not explicitly initialize each field,
  // instead relying on default initialization for the unspecified fields. In
  // particular, the owner_ field (a pthread_t) is not explicitly initialized.
  // This allows initialization to work whether pthread_t is a scalar or struct.
  // The flag -Wmissing-field-initializers must not be specified for this to work.
  # define GTEST_DEFINE_STATIC_MUTEX_(mutex) \
      ::testing::internal::MutexBase mutex = { PTHREAD_MUTEX_INITIALIZER, false }
  
  // The Mutex class can only be used for mutexes created at runtime. It
  // shares its API with MutexBase otherwise.
  class Mutex : public MutexBase {
   public:
    Mutex() {
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_init(&mutex_, NULL));
      has_owner_ = false;
    }
    ~Mutex() {
      GTEST_CHECK_POSIX_SUCCESS_(pthread_mutex_destroy(&mutex_));
    }
  
   private:
    GTEST_DISALLOW_COPY_AND_ASSIGN_(Mutex);
  };
  
  // We cannot name this class MutexLock as the ctor declaration would
  // conflict with a macro named MutexLock, which is defined on some
  // platforms.  Hence the typedef trick below.
  class GTestMutexLock {
   public:
    explicit GTestMutexLock(MutexBase* mutex)
        : mutex_(mutex) { mutex_->Lock(); }
  
    ~GTestMutexLock() { mutex_->Unlock(); }
  
   private:
    MutexBase* const mutex_;
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(GTestMutexLock);
  };
  
  typedef GTestMutexLock MutexLock;
  
  // Helpers for ThreadLocal.
  
  // pthread_key_create() requires DeleteThreadLocalValue() to have
  // C-linkage.  Therefore it cannot be templatized to access
  // ThreadLocal<T>.  Hence the need for class
  // ThreadLocalValueHolderBase.
  class ThreadLocalValueHolderBase {
   public:
    virtual ~ThreadLocalValueHolderBase() {}
  };
  
  // Called by pthread to delete thread-local data stored by
  // pthread_setspecific().
  extern "C" inline void DeleteThreadLocalValue(void* value_holder) {
    delete static_cast<ThreadLocalValueHolderBase*>(value_holder);
  }
  
  // Implements thread-local storage on pthreads-based systems.
  //
  //   // Thread 1
  //   ThreadLocal<int> tl(100);  // 100 is the default value for each thread.
  //
  //   // Thread 2
  //   tl.set(150);  // Changes the value for thread 2 only.
  //   EXPECT_EQ(150, tl.get());
  //
  //   // Thread 1
  //   EXPECT_EQ(100, tl.get());  // In thread 1, tl has the original value.
  //   tl.set(200);
  //   EXPECT_EQ(200, tl.get());
  //
  // The template type argument T must have a public copy constructor.
  // In addition, the default ThreadLocal constructor requires T to have
  // a public default constructor.
  //
  // An object managed for a thread by a ThreadLocal instance is deleted
  // when the thread exits.  Or, if the ThreadLocal instance dies in
  // that thread, when the ThreadLocal dies.  It's the user's
  // responsibility to ensure that all other threads using a ThreadLocal
  // have exited when it dies, or the per-thread objects for those
  // threads will not be deleted.
  //
  // Google Test only uses global ThreadLocal objects.  That means they
  // will die after main() has returned.  Therefore, no per-thread
  // object managed by Google Test will be leaked as long as all threads
  // using Google Test have exited when main() returns.
  template <typename T>
  class ThreadLocal {
   public:
    ThreadLocal() : key_(CreateKey()),
                    default_() {}
    explicit ThreadLocal(const T& value) : key_(CreateKey()),
                                           default_(value) {}
  
    ~ThreadLocal() {
      // Destroys the managed object for the current thread, if any.
      DeleteThreadLocalValue(pthread_getspecific(key_));
  
      // Releases resources associated with the key.  This will *not*
      // delete managed objects for other threads.
      GTEST_CHECK_POSIX_SUCCESS_(pthread_key_delete(key_));
    }
  
    T* pointer() { return GetOrCreateValue(); }
    const T* pointer() const { return GetOrCreateValue(); }
    const T& get() const { return *pointer(); }
    void set(const T& value) { *pointer() = value; }
  
   private:
    // Holds a value of type T.
    class ValueHolder : public ThreadLocalValueHolderBase {
     public:
      explicit ValueHolder(const T& value) : value_(value) {}
  
      T* pointer() { return &value_; }
  
     private:
      T value_;
      GTEST_DISALLOW_COPY_AND_ASSIGN_(ValueHolder);
    };
  
    static pthread_key_t CreateKey() {
      pthread_key_t key;
      // When a thread exits, DeleteThreadLocalValue() will be called on
      // the object managed for that thread.
      GTEST_CHECK_POSIX_SUCCESS_(
          pthread_key_create(&key, &DeleteThreadLocalValue));
      return key;
    }
  
    T* GetOrCreateValue() const {
      ThreadLocalValueHolderBase* const holder =
          static_cast<ThreadLocalValueHolderBase*>(pthread_getspecific(key_));
      if (holder != NULL) {
        return CheckedDowncastToActualType<ValueHolder>(holder)->pointer();
      }
  
      ValueHolder* const new_holder = new ValueHolder(default_);
      ThreadLocalValueHolderBase* const holder_base = new_holder;
      GTEST_CHECK_POSIX_SUCCESS_(pthread_setspecific(key_, holder_base));
      return new_holder->pointer();
    }
  
    // A key pthreads uses for looking up per-thread values.
    const pthread_key_t key_;
    const T default_;  // The default value for each thread.
  
    GTEST_DISALLOW_COPY_AND_ASSIGN_(ThreadLocal);
  };
  
  # define GTEST_IS_THREADSAFE 1
  
  #else  // GTEST_HAS_PTHREAD
  
  // A dummy implementation of synchronization primitives (mutex, lock,
  // and thread-local variable).  Necessary for compiling Google Test where
  // mutex is not supported - using Google Test in multiple threads is not
  // supported on such platforms.
  
  class Mutex {
   public:
    Mutex() {}
    void Lock() {}
    void Unlock() {}
    void AssertHeld() const {}
  };
  
  # define GTEST_DECLARE_STATIC_MUTEX_(mutex) \
    extern ::testing::internal::Mutex mutex
  
  # define GTEST_DEFINE_STATIC_MUTEX_(mutex) ::testing::internal::Mutex mutex
  
  class GTestMutexLock {
   public:
    explicit GTestMutexLock(Mutex*) {}  // NOLINT
  };
  
  typedef GTestMutexLock MutexLock;
  
  template <typename T>
  class ThreadLocal {
   public:
    ThreadLocal() : value_() {}
    explicit ThreadLocal(const T& value) : value_(value) {}
    T* pointer() { return &value_; }
    const T* pointer() const { return &value_; }
    const T& get() const { return value_; }
    void set(const T& value) { value_ = value; }
   private:
    T value_;
  };
  
  // The above synchronization primitives have dummy implementations.
  // Therefore Google Test is not thread-safe.
  # define GTEST_IS_THREADSAFE 0
  
  #endif  // GTEST_HAS_PTHREAD
  
  // Returns the number of threads running in the process, or 0 to indicate that
  // we cannot detect it.
  GTEST_API_ size_t GetThreadCount();
  
  // Passing non-POD classes through ellipsis (...) crashes the ARM
  // compiler and generates a warning in Sun Studio before 12u4. The Nokia Symbian
  // and the IBM XL C/C++ compiler try to instantiate a copy constructor
  // for objects passed through ellipsis (...), failing for uncopyable
  // objects.  We define this to ensure that only POD is passed through
  // ellipsis on these systems.
  #if defined(__SYMBIAN32__) || defined(__IBMCPP__) || \
       (defined(__SUNPRO_CC) && __SUNPRO_CC < 0x5130)
  // We lose support for NULL detection where the compiler doesn't like
  // passing non-POD classes through ellipsis (...).
  # define GTEST_ELLIPSIS_NEEDS_POD_ 1
  #else
  # define GTEST_CAN_COMPARE_NULL 1
  #endif
  
  // The Nokia Symbian and IBM XL C/C++ compilers cannot decide between
  // const T& and const T* in a function template.  These compilers
  // _can_ decide between class template specializations for T and T*,
  // so a tr1::type_traits-like is_pointer works.
  #if defined(__SYMBIAN32__) || defined(__IBMCPP__)
  # define GTEST_NEEDS_IS_POINTER_ 1
  #endif
  
  template <bool bool_value>
  struct bool_constant {
    typedef bool_constant<bool_value> type;
    static const bool value = bool_value;
  };
  template <bool bool_value> const bool bool_constant<bool_value>::value;
  
  typedef bool_constant<false> false_type;
  typedef bool_constant<true> true_type;
  
  template <typename T>
  struct is_pointer : public false_type {};
  
  template <typename T>
  struct is_pointer<T*> : public true_type {};
  
  template <typename Iterator>
  struct IteratorTraits {
    typedef typename Iterator::value_type value_type;
  };
  
  template <typename T>
  struct IteratorTraits<T*> {
    typedef T value_type;
  };
  
  template <typename T>
  struct IteratorTraits<const T*> {
    typedef T value_type;
  };
  
  #if GTEST_OS_WINDOWS
  # define GTEST_PATH_SEP_ "\\"
  # define GTEST_HAS_ALT_PATH_SEP_ 1
  // The biggest signed integer type the compiler supports.
  typedef __int64 BiggestInt;
  #else
  # define GTEST_PATH_SEP_ "/"
  # define GTEST_HAS_ALT_PATH_SEP_ 0
  typedef long long BiggestInt;  // NOLINT
  #endif  // GTEST_OS_WINDOWS
  
  // Utilities for char.
  
  // isspace(int ch) and friends accept an unsigned char or EOF.  char
  // may be signed, depending on the compiler (or compiler flags).
  // Therefore we need to cast a char to unsigned char before calling
  // isspace(), etc.
  
  inline bool IsAlpha(char ch) {
    return isalpha(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsAlNum(char ch) {
    return isalnum(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsDigit(char ch) {
    return isdigit(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsLower(char ch) {
    return islower(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsSpace(char ch) {
    return isspace(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsUpper(char ch) {
    return isupper(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsXDigit(char ch) {
    return isxdigit(static_cast<unsigned char>(ch)) != 0;
  }
  inline bool IsXDigit(wchar_t ch) {
    const unsigned char low_byte = static_cast<unsigned char>(ch);
    return ch == low_byte && isxdigit(low_byte) != 0;
  }
  
  inline char ToLower(char ch) {
    return static_cast<char>(tolower(static_cast<unsigned char>(ch)));
  }
  inline char ToUpper(char ch) {
    return static_cast<char>(toupper(static_cast<unsigned char>(ch)));
  }
  
  // The testing::internal::posix namespace holds wrappers for common
  // POSIX functions.  These wrappers hide the differences between
  // Windows/MSVC and POSIX systems.  Since some compilers define these
  // standard functions as macros, the wrapper cannot have the same name
  // as the wrapped function.
  
  namespace posix {
  
  // Functions with a different name on Windows.
  
  #if GTEST_OS_WINDOWS
  
  typedef struct _stat StatStruct;
  
  # ifdef __BORLANDC__
  inline int IsATTY(int fd) { return isatty(fd); }
  inline int StrCaseCmp(const char* s1, const char* s2) {
    return stricmp(s1, s2);
  }
  inline char* StrDup(const char* src) { return strdup(src); }
  # else  // !__BORLANDC__
  #  if GTEST_OS_WINDOWS_MOBILE
  inline int IsATTY(int /* fd */) { return 0; }
  #  else
  inline int IsATTY(int fd) { return _isatty(fd); }
  #  endif  // GTEST_OS_WINDOWS_MOBILE
  inline int StrCaseCmp(const char* s1, const char* s2) {
    return _stricmp(s1, s2);
  }
  inline char* StrDup(const char* src) { return _strdup(src); }
  # endif  // __BORLANDC__
  
  # if GTEST_OS_WINDOWS_MOBILE
  inline int FileNo(FILE* file) { return reinterpret_cast<int>(_fileno(file)); }
  // Stat(), RmDir(), and IsDir() are not needed on Windows CE at this
  // time and thus not defined there.
  # else
  inline int FileNo(FILE* file) { return _fileno(file); }
  inline int Stat(const char* path, StatStruct* buf) { return _stat(path, buf); }
  inline int RmDir(const char* dir) { return _rmdir(dir); }
  inline bool IsDir(const StatStruct& st) {
    return (_S_IFDIR & st.st_mode) != 0;
  }
  # endif  // GTEST_OS_WINDOWS_MOBILE
  
  #else
  
  typedef struct stat StatStruct;
  
  inline int FileNo(FILE* file) { return fileno(file); }
  inline int IsATTY(int fd) { return isatty(fd); }
  inline int Stat(const char* path, StatStruct* buf) { return stat(path, buf); }
  inline int StrCaseCmp(const char* s1, const char* s2) {
    return strcasecmp(s1, s2);
  }
  inline char* StrDup(const char* src) { return strdup(src); }
  inline int RmDir(const char* dir) { return rmdir(dir); }
  inline bool IsDir(const StatStruct& st) { return S_ISDIR(st.st_mode); }
  
  #endif  // GTEST_OS_WINDOWS
  
  // Functions deprecated by MSVC 8.0.
  
  #ifdef _MSC_VER
  // Temporarily disable warning 4996 (deprecated function).
  # pragma warning(push)
  # pragma warning(disable:4996)
  #endif
  
  inline const char* StrNCpy(char* dest, const char* src, size_t n) {
    return strncpy(dest, src, n);
  }
  
  // ChDir(), FReopen(), FDOpen(), Read(), Write(), Close(), and
  // StrError() aren't needed on Windows CE at this time and thus not
  // defined there.
  
  #if !GTEST_OS_WINDOWS_MOBILE
  inline int ChDir(const char* dir) { return chdir(dir); }
  #endif
  inline FILE* FOpen(const char* path, const char* mode) {
    return fopen(path, mode);
  }
  #if !GTEST_OS_WINDOWS_MOBILE
  inline FILE *FReopen(const char* path, const char* mode, FILE* stream) {
    return freopen(path, mode, stream);
  }
  inline FILE* FDOpen(int fd, const char* mode) { return fdopen(fd, mode); }
  #endif
  inline int FClose(FILE* fp) { return fclose(fp); }
  #if !GTEST_OS_WINDOWS_MOBILE
  inline int Read(int fd, void* buf, unsigned int count) {
    return static_cast<int>(read(fd, buf, count));
  }
  inline int Write(int fd, const void* buf, unsigned int count) {
    return static_cast<int>(write(fd, buf, count));
  }
  inline int Close(int fd) { return close(fd); }
  inline const char* StrError(int errnum) { return strerror(errnum); }
  #endif
  inline const char* GetEnv(const char* name) {
  #if GTEST_OS_WINDOWS_MOBILE
    // We are on Windows CE, which has no environment variables.
    return NULL;
  #elif defined(__BORLANDC__) || defined(__SunOS_5_8) || defined(__SunOS_5_9)
    // Environment variables which we programmatically clear will be set to the
    // empty string rather than unset (NULL).  Handle that case.
    const char* const env = getenv(name);
    return (env != NULL && env[0] != '\0') ? env : NULL;
  #else
    return getenv(name);
  #endif
  }
  
  #ifdef _MSC_VER
  # pragma warning(pop)  // Restores the warning state.
  #endif
  
  #if GTEST_OS_WINDOWS_MOBILE
  // Windows CE has no C library. The abort() function is used in
  // several places in Google Test. This implementation provides a reasonable
  // imitation of standard behaviour.
  void Abort();
  #else
  inline void Abort() { abort(); }
  #endif  // GTEST_OS_WINDOWS_MOBILE
  
  }  // namespace posix
  
  // MSVC "deprecates" snprintf and issues warnings wherever it is used.  In
  // order to avoid these warnings, we need to use _snprintf or _snprintf_s on
  // MSVC-based platforms.  We map the GTEST_SNPRINTF_ macro to the appropriate
  // function in order to achieve that.  We use macro definition here because
  // snprintf is a variadic function.
  #if _MSC_VER >= 1400 && !GTEST_OS_WINDOWS_MOBILE
  // MSVC 2005 and above support variadic macros.
  # define GTEST_SNPRINTF_(buffer, size, format, ...) \
       _snprintf_s(buffer, size, size, format, __VA_ARGS__)
  #elif defined(_MSC_VER)
  // Windows CE does not define _snprintf_s and MSVC prior to 2005 doesn't
  // complain about _snprintf.
  # define GTEST_SNPRINTF_ _snprintf
  #else
  # define GTEST_SNPRINTF_ snprintf
  #endif
  
  // The maximum number a BiggestInt can represent.  This definition
  // works no matter BiggestInt is represented in one's complement or
  // two's complement.
  //
  // We cannot rely on numeric_limits in STL, as __int64 and long long
  // are not part of standard C++ and numeric_limits doesn't need to be
  // defined for them.
  const BiggestInt kMaxBiggestInt =
      ~(static_cast<BiggestInt>(1) << (8*sizeof(BiggestInt) - 1));
  
  // This template class serves as a compile-time function from size to
  // type.  It maps a size in bytes to a primitive type with that
  // size. e.g.
  //
  //   TypeWithSize<4>::UInt
  //
  // is typedef-ed to be unsigned int (unsigned integer made up of 4
  // bytes).
  //
  // Such functionality should belong to STL, but I cannot find it
  // there.
  //
  // Google Test uses this class in the implementation of floating-point
  // comparison.
  //
  // For now it only handles UInt (unsigned int) as that's all Google Test
  // needs.  Other types can be easily added in the future if need
  // arises.
  template <size_t size>
  class TypeWithSize {
   public:
    // This prevents the user from using TypeWithSize<N> with incorrect
    // values of N.
    typedef void UInt;
  };
  
  // The specialization for size 4.
  template <>
  class TypeWithSize<4> {
   public:
    // unsigned int has size 4 in both gcc and MSVC.
    //
    // As base/basictypes.h doesn't compile on Windows, we cannot use
    // uint32, uint64, and etc here.
    typedef int Int;
    typedef unsigned int UInt;
  };
  
  // The specialization for size 8.
  template <>
  class TypeWithSize<8> {
   public:
  #if GTEST_OS_WINDOWS
    typedef __int64 Int;
    typedef unsigned __int64 UInt;
  #else
    typedef long long Int;  // NOLINT
    typedef unsigned long long UInt;  // NOLINT
  #endif  // GTEST_OS_WINDOWS
  };
  
  // Integer types of known sizes.
  typedef TypeWithSize<4>::Int Int32;
  typedef TypeWithSize<4>::UInt UInt32;
  typedef TypeWithSize<8>::Int Int64;
  typedef TypeWithSize<8>::UInt UInt64;
  typedef TypeWithSize<8>::Int TimeInMillis;  // Represents time in milliseconds.
  
  // Utilities for command line flags and environment variables.
  
  // Macro for referencing flags.
  #define GTEST_FLAG(name) FLAGS_gtest_##name
  
  // Macros for declaring flags.
  #define GTEST_DECLARE_bool_(name) GTEST_API_ extern bool GTEST_FLAG(name)
  #define GTEST_DECLARE_int32_(name) \
      GTEST_API_ extern ::testing::internal::Int32 GTEST_FLAG(name)
  #define GTEST_DECLARE_string_(name) \
      GTEST_API_ extern ::std::string GTEST_FLAG(name)
  
  // Macros for defining flags.
  #define GTEST_DEFINE_bool_(name, default_val, doc) \
      GTEST_API_ bool GTEST_FLAG(name) = (default_val)
  #define GTEST_DEFINE_int32_(name, default_val, doc) \
      GTEST_API_ ::testing::internal::Int32 GTEST_FLAG(name) = (default_val)
  #define GTEST_DEFINE_string_(name, default_val, doc) \
      GTEST_API_ ::std::string GTEST_FLAG(name) = (default_val)
  
  // Thread annotations
  #define GTEST_EXCLUSIVE_LOCK_REQUIRED_(locks)
  #define GTEST_LOCK_EXCLUDED_(locks)
  
  // Parses 'str' for a 32-bit signed integer.  If successful, writes the result
  // to *value and returns true; otherwise leaves *value unchanged and returns
  // false.
  // TODO(chandlerc): Find a better way to refactor flag and environment parsing
  // out of both gtest-port.cc and gtest.cc to avoid exporting this utility
  // function.
  bool ParseInt32(const Message& src_text, const char* str, Int32* value);
  
  // Parses a bool/Int32/string from the environment variable
  // corresponding to the given Google Test flag.
  bool BoolFromGTestEnv(const char* flag, bool default_val);
  GTEST_API_ Int32 Int32FromGTestEnv(const char* flag, Int32 default_val);
  const char* StringFromGTestEnv(const char* flag, const char* default_val);
  
  }  // namespace internal
  }  // namespace testing
  
  #endif  // GTEST_INCLUDE_GTEST_INTERNAL_GTEST_PORT_H_
  