• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* boost limits_test.cpp   test your <limits> file for important
2  *
3  * Copyright Jens Maurer 2000
4  * Distributed under the Boost Software License, Version 1.0. (See
5  * accompanying file LICENSE_1_0.txt or copy at
6  * http://www.boost.org/LICENSE_1_0.txt)
7  *
8  * $Id$
9  */
10 
11 #include <boost/limits.hpp>
12 #include <boost/detail/lightweight_main.hpp>
13 #include <boost/core/lightweight_test.hpp>
14 #include <iostream>
15 
16 /*
17  * General portability note:
18  * MSVC mis-compiles explicit function template instantiations.
19  * For example, f<A>() and f<B>() are both compiled to call f<A>().
20  * BCC is unable to implicitly convert a "const char *" to a std::string
21  * when using explicit function template instantiations.
22  *
23  * Therefore, avoid explicit function template instantiations.
24  */
25 #if defined(BOOST_MSVC) && (BOOST_MSVC <= 1300)
make_char_numeric_for_streaming(T x)26 template<typename T> inline T make_char_numeric_for_streaming(T x) { return x; }
27 namespace fix{
make_char_numeric_for_streaming(char c)28 inline int make_char_numeric_for_streaming(char c) { return c; }
make_char_numeric_for_streaming(signed char c)29 inline int make_char_numeric_for_streaming(signed char c) { return c; }
make_char_numeric_for_streaming(unsigned char c)30 inline int make_char_numeric_for_streaming(unsigned char c) { return c; }
31 }
32 using namespace fix;
33 #  if defined(_YVALS) && !defined(_CPPLIB_VER) && !defined(__SGI_STL_PORT) && !defined(_STLPORT_VERSION)
34 // fix for missing operator<< in original Dinkumware lib:
operator <<(std::ostream & os,__int64 i)35 std::ostream& operator<<(std::ostream& os, __int64 i )
36 {
37     char buf[80];
38     sprintf(buf,"%I64d", i );
39     os << buf;
40     return os;
41 }
operator <<(std::ostream & os,unsigned __int64 i)42 std::ostream& operator<<(std::ostream& os, unsigned __int64 i )
43 {
44     char buf[80];
45     sprintf(buf,"%I64u", i );
46     os << buf;
47     return os;
48 }
49 #  endif
50 #else
make_char_numeric_for_streaming(T x)51 template<typename T> inline T make_char_numeric_for_streaming(T x) { return x; }
make_char_numeric_for_streaming(char c)52 inline int make_char_numeric_for_streaming(char c) { return c; }
make_char_numeric_for_streaming(signed char c)53 inline int make_char_numeric_for_streaming(signed char c) { return c; }
make_char_numeric_for_streaming(unsigned char c)54 inline int make_char_numeric_for_streaming(unsigned char c) { return c; }
make_char_numeric_for_streaming(wchar_t c)55 inline int make_char_numeric_for_streaming(wchar_t c) { return c; }
56 #endif
57 
58 #if (defined(_GLIBCPP_VERSION) || defined(_GLIBCXX_VERSION)) \
59    && defined(BOOST_HAS_LONG_LONG) \
60    && !defined(_GLIBCPP_USE_LONG_LONG) \
61    && !defined(_GLIBCXX_USE_LONG_LONG)
62 //
63 // Some libstdc++ versions have numeric_limits<long long> but no
64 // iostream support for long long.  TODO, find a better fix!!
65 //
operator <<(std::ostream & os,long long i)66 std::ostream& operator<<(std::ostream& os, long long i )
67 {
68     return os << static_cast<long double>(i);
69 }
operator <<(std::ostream & os,unsigned long long i)70 std::ostream& operator<<(std::ostream& os, unsigned long long i )
71 {
72     return os << static_cast<long double>(i);
73 }
74 #endif
75 
76 template<class T>
test_integral_limits(const T &,const char * msg)77 void test_integral_limits(const T &, const char * msg)
78 {
79   typedef std::numeric_limits<T> lim;
80   std::cout << "Testing " << msg
81             << " (size " << sizeof(T) << ")"
82             << " min: " << make_char_numeric_for_streaming((lim::min)())
83             << ", max: " << make_char_numeric_for_streaming((lim::max)())
84             << std::endl;
85 
86   BOOST_TEST(static_cast<bool>(lim::is_specialized));
87   BOOST_TEST(static_cast<bool>(lim::is_integer));
88   // BOOST_TEST(lim::is_modulo);
89   BOOST_TEST(static_cast<bool>((lim::min)() < (lim::max)()));
90 }
91 
92 template <class T>
print_hex_val(T t,const char * name)93 void print_hex_val(T t, const char* name)
94 {
95   const unsigned char* p = (const unsigned char*)&t;
96   std::cout << "hex value of " << name << " is: ";
97   for (unsigned int i = 0; i < sizeof(T); ++i) {
98     if(p[i] <= 0xF)
99       std::cout << "0";
100     std::cout << std::hex << (int)p[i];
101   }
102   std::cout << std::dec << std::endl;
103 }
104 
105 template<class T>
test_float_limits(const T &,const char * msg)106 void test_float_limits(const T &, const char * msg)
107 {
108   std::cout << "\nTesting " << msg << std::endl;
109   typedef std::numeric_limits<T> lim;
110 
111   BOOST_TEST(static_cast<bool>(lim::is_specialized));
112   BOOST_TEST(static_cast<bool>(!lim::is_modulo));
113   BOOST_TEST(static_cast<bool>(!lim::is_integer));
114   BOOST_TEST(static_cast<bool>(lim::is_signed));
115 
116   const T infinity = lim::infinity();
117   const T qnan = lim::quiet_NaN();
118   const T snan = lim::signaling_NaN();
119 
120   std::cout << "IEEE-compatible: " << lim::is_iec559
121        << ", traps: " << lim::traps
122        << ", bounded: " << lim::is_bounded
123        << ", exact: " << lim::is_exact << '\n'
124        << "min: " << (lim::min)() << ", max: " << (lim::max)() << '\n'
125        << "infinity: " << infinity << ", QNaN: " << qnan << '\n';
126   print_hex_val((lim::max)(), "max");
127   print_hex_val(infinity, "infinity");
128   print_hex_val(qnan, "qnan");
129   print_hex_val(snan, "snan");
130 
131   BOOST_TEST((lim::max)() > 1000);
132   BOOST_TEST((lim::min)() > 0);
133   BOOST_TEST((lim::min)() < 0.001);
134   BOOST_TEST(lim::epsilon() > 0);
135 
136   if(lim::is_iec559) {
137     BOOST_TEST(static_cast<bool>(lim::has_infinity));
138     BOOST_TEST(static_cast<bool>(lim::has_quiet_NaN));
139     BOOST_TEST(static_cast<bool>(lim::has_signaling_NaN));
140   } else {
141     std::cout << "Does not claim IEEE conformance" << std::endl;
142   }
143 
144   if(lim::has_infinity) {
145     // Make sure those values are not 0 or similar nonsense.
146     // Infinity must compare as if larger than the maximum representable value.
147     BOOST_TEST(infinity > (lim::max)());
148     BOOST_TEST(-infinity < -(lim::max)());
149   } else {
150     std::cout << "Does not have infinity" << std::endl;
151   }
152 
153   if(lim::has_quiet_NaN) {
154     // NaNs shall always compare "false" when compared for equality
155     // If one of these fail, your compiler may be optimizing incorrectly,
156     // or the standard library is incorrectly configured.
157     BOOST_TEST(! (qnan == 42));
158     BOOST_TEST(qnan != 42);
159     if(lim::is_iec559)
160     {
161       BOOST_TEST(! (qnan == qnan));
162       BOOST_TEST(qnan != qnan);
163     }
164 
165     // The following tests may cause arithmetic traps.
166     // BOOST_TEST(! (qnan < 42));
167     // BOOST_TEST(! (qnan > 42));
168     // BOOST_TEST(! (qnan <= 42));
169     // BOOST_TEST(! (qnan >= 42));
170   } else {
171     std::cout << "Does not have QNaN" << std::endl;
172   }
173 }
174 
175 
cpp_main(int,char * [])176 int cpp_main(int, char*[])
177 {
178   test_integral_limits(bool(), "bool");
179   test_integral_limits(char(), "char");
180   typedef signed char signed_char;
181   test_integral_limits(signed_char(), "signed char");
182   typedef unsigned char unsigned_char;
183   test_integral_limits(unsigned_char(), "unsigned char");
184   test_integral_limits(wchar_t(), "wchar_t");
185   test_integral_limits(short(), "short");
186   typedef unsigned short unsigned_short;
187   test_integral_limits(unsigned_short(), "unsigned short");
188   test_integral_limits(int(), "int");
189   typedef unsigned int unsigned_int;
190   test_integral_limits(unsigned_int(), "unsigned int");
191   test_integral_limits(long(), "long");
192   typedef unsigned long unsigned_long;
193   test_integral_limits(unsigned_long(), "unsigned long");
194 #if defined(BOOST_HAS_LONG_LONG)
195   test_integral_limits(::boost::long_long_type(), "long long");
196   test_integral_limits(::boost::ulong_long_type(), "unsigned long long");
197 #endif
198 #ifdef BOOST_HAS_MS_INT64
199   typedef __int64 long_long2;
200   test_integral_limits(long_long2(), "__int64");
201   typedef unsigned __int64 unsigned_long_long2;
202   test_integral_limits(unsigned_long_long2(), "unsigned __int64");
203 #endif
204 
205   test_float_limits(float(), "float");
206   test_float_limits(double(), "double");
207   typedef long double long_double;
208   test_float_limits(long_double(), "long double");
209   // Some compilers don't pay attention to std:3.6.1/5 and issue a
210   // warning here if "return 0;" is omitted.
211   return boost::report_errors();
212 }
213 
214 
215