Use std::random

6 files changed, 54 insertions, 242 deletions

diff --git a/configure.ac b/configure.ac
index 74dcb8f17..469673127 100644
--- a/configure.ac
+++ b/configure.ac
@@ -783,6 +783,43 @@ int main(int, char **)
 	])
 dnl }}}
 
+dnl {{{ std::random
+random_is_tr1=
+AC_MSG_CHECKING([for c++0x-compliant <random>])
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+#include <random>
+#include <ctime>
+int main(int, char **)
+{
+	std::mt19937 rand(std::time(0));
+	std::uniform_int_distribution<int> dist(0, 9);
+	return dist(rand);
+}
+])],
+	[AC_MSG_RESULT([yes])],
+	[AC_MSG_RESULT([no])
+	 AC_MSG_CHECKING([for tr1-compliant <random>])
+	 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+#include <random>
+#include <ctime>
+int main(int, char **)
+{
+	std::mt19937 rand(std::time(0));
+	std::uniform_int<int> dist(0, 9);
+	return dist(rand);
+}
+	 ])],
+	  [AC_MSG_RESULT([yes])
+	   random_is_tr1=yes],
+	  [AC_MSG_RESULT([no])
+	   AC_MSG_ERROR([Your compiler does not support <random>])])
+	])
+
+if test x$random_is_tr1 = xyes ; then
+	PALUDIS_CXXFLAGS="${PALUDIS_CXXFLAGS} -DPALUDIS_RANDOM_IS_TR1=1"
+fi
+dnl }}}
+
 dnl {{{ c++0x default and deleted functions
 AC_MSG_CHECKING([for c++0x default and deleted functions])
 AC_COMPILE_IFELSE([AC_LANG_SOURCE([
diff --git a/paludis/repositories/e/e_repository.cc b/paludis/repositories/e/e_repository.cc
index e23350883..0c9f43639 100644
--- a/paludis/repositories/e/e_repository.cc
+++ b/paludis/repositories/e/e_repository.cc
@@ -82,7 +82,6 @@
 #include <paludis/util/options.hh>
 #include <paludis/util/pimp-impl.hh>
 #include <paludis/util/process.hh>
-#include <paludis/util/random.hh>
 #include <paludis/util/rmd160.hh>
 #include <paludis/util/safe_ifstream.hh>
 #include <paludis/util/safe_ofstream.hh>
@@ -98,6 +97,7 @@
 #include <paludis/util/wrapped_forward_iterator.hh>
 #include <paludis/util/wrapped_output_iterator.hh>
 
+#include <random>
 #include <functional>
 #include <unordered_map>
 #include <map>
@@ -105,6 +105,7 @@
 #include <algorithm>
 #include <vector>
 #include <list>
+#include <ctime>
 
 #include <strings.h>
 #include <ctype.h>
@@ -644,6 +645,19 @@ ERepository::arch_flags() const
     return _imp->arch_flags;
 }
 
+namespace
+{
+    struct Randomator
+    {
+        std::mt19937 & rand;
+
+        int operator() (int n)
+        {
+            return rand() % n;
+        }
+    };
+}
+
 void
 ERepository::need_mirrors() const
 {
@@ -666,8 +680,8 @@ ERepository::need_mirrors() const
                     if (! ee.empty())
                     {
                         /* pick up to five random mirrors only */
-                        static Random r;
-                        std::random_shuffle(next(ee.begin()), ee.end(), r);
+                        std::mt19937 random(std::time(0));
+                        std::random_shuffle(next(ee.begin()), ee.end(), Randomator{random});
                         if (ee.size() > 6)
                             ee.resize(6);
 
diff --git a/paludis/util/files.m4 b/paludis/util/files.m4
index d98aae3b3..d475e8f9f 100644
--- a/paludis/util/files.m4
+++ b/paludis/util/files.m4
@@ -64,7 +64,6 @@ add(`pool',                              `hh', `cc', `impl', `test')
 add(`pretty_print',                      `hh', `cc', `test')
 add(`process',                           `hh', `cc', `fwd', `gtest', `testscript')
 add(`pty',                               `hh', `cc', `gtest')
-add(`random',                            `hh', `cc', `test')
 add(`realpath',                          `hh', `cc', `gtest', `testscript')
 add(`remove_shared_ptr',                 `hh')
 add(`return_literal_function',           `hh', `cc', `fwd', `gtest')
diff --git a/paludis/util/random.cc b/paludis/util/random.cc
deleted file mode 100644
index 74bf2d480..000000000
--- a/paludis/util/random.cc
+++ /dev/null
@@ -1,37 +0,0 @@
-/* vim: set sw=4 sts=4 et foldmethod=syntax : */
-
-/*
- * Copyright (c) 2006, 2007 Ciaran McCreesh
- *
- * This file is part of the Paludis package manager. Paludis is free software;
- * you can redistribute it and/or modify it under the terms of the GNU General
- * Public License version 2, as published by the Free Software Foundation.
- *
- * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
- * details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place, Suite 330, Boston, MA  02111-1307  USA
- */
-
-#include "random.hh"
-#include <time.h>
-
-using namespace paludis;
-
-uint32_t Random::global_seed(0xdeadbeef ^ ::time(0));
-
-Random::Random(uint32_t seed) :
-    local_seed(seed)
-{
-}
-
-Random::Random() :
-    local_seed(global_seed ^ ((::time(0) >> 16) | (::time(0) << 16)))
-{
-    global_seed += local_seed;
-}
-
diff --git a/paludis/util/random.hh b/paludis/util/random.hh
deleted file mode 100644
index a5d391fc0..000000000
--- a/paludis/util/random.hh
+++ /dev/null
@@ -1,82 +0,0 @@
-/* vim: set sw=4 sts=4 et foldmethod=syntax : */
-
-/*
- * Copyright (c) 2006, 2007, 2008, 2009 Ciaran McCreesh
- *
- * This file is part of the Paludis package manager. Paludis is free software;
- * you can redistribute it and/or modify it under the terms of the GNU General
- * Public License version 2, as published by the Free Software Foundation.
- *
- * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
- * details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place, Suite 330, Boston, MA  02111-1307  USA
- */
-
-#ifndef PALUDIS_GUARD_PALUDIS_UTIL_RANDOM_HH
-#define PALUDIS_GUARD_PALUDIS_UTIL_RANDOM_HH 1
-
-#include <cstdlib>
-#include <inttypes.h>
-#include <paludis/util/attributes.hh>
-
-/** \file
- * Declarations for the Random class.
- *
- * \ingroup g_utils
- *
- * \section Examples
- *
- * - None at this time.
- */
-
-namespace paludis
-{
-    /**
-     * A basic random number generator class, which is not suitable for
-     * cryptography but is fast and reasonably pseudorandom.
-     *
-     * See \ref TCppPL 22.7 for justification. See \ref TaoCP2 3.2.1 for the
-     * basic algorithm and \ref AppCrypt 16.1 for the choice of numbers.
-     *
-     * \ingroup g_utils
-     * \nosubgrouping
-     */
-    class PALUDIS_VISIBLE Random
-    {
-        private:
-            static uint32_t global_seed;
-            uint32_t local_seed;
-
-            static const uint32_t _a = 2416;
-            static const uint32_t _b = 374441;
-            static const uint32_t _m = 1771875;
-
-        public:
-            ///\name Basic operations
-            ///\{
-
-            /// Constructor, with a seed.
-            Random(uint32_t seed);
-
-            /// Constructor, with a magic random seed.
-            Random();
-
-            ///\}
-
-            /// Fetch a random number in (0, max]
-            template <typename DiffType_>
-            DiffType_ operator() (DiffType_ max)
-            {
-                local_seed = (_a * local_seed + _b) % _m;
-                double t(static_cast<double>(local_seed) / static_cast<double>(_m));
-                return static_cast<DiffType_>(t * max);
-            }
-    };
-}
-
-#endif
diff --git a/paludis/util/random_TEST.cc b/paludis/util/random_TEST.cc
deleted file mode 100644
index 87bcadd84..000000000
--- a/paludis/util/random_TEST.cc
+++ /dev/null
@@ -1,119 +0,0 @@
-/* vim: set sw=4 sts=4 et foldmethod=syntax : */
-
-/*
- * Copyright (c) 2006 Ciaran McCreesh
- *
- * This file is part of the Paludis package manager. Paludis is free software;
- * you can redistribute it and/or modify it under the terms of the GNU General
- * Public License version 2, as published by the Free Software Foundation.
- *
- * Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
- * details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
- * Place, Suite 330, Boston, MA  02111-1307  USA
- */
-
-#include "random.hh"
-#include <test/test_framework.hh>
-#include <test/test_runner.hh>
-#include <vector>
-#include <algorithm>
-
-/** \file
- * Test cases for paludis::Random.
- *
- */
-
-using namespace paludis;
-using namespace test;
-
-namespace
-{
-    struct RandomUpTo
-    {
-        Random random;
-        unsigned max;
-
-        RandomUpTo(const Random & r, const unsigned m) :
-            random(r),
-            max(m)
-        {
-        }
-
-        int operator() ()
-        {
-            return random(max);
-        }
-    };
-
-    inline double square(double v)
-    {
-        return v * v;
-    }
-}
-
-namespace test_cases
-{
-    /**
-     * \test Test Random distibutions using counts.
-     *
-     */
-    struct RandomDistributionCountsTest : TestCase
-    {
-        RandomDistributionCountsTest() : TestCase("distribution (counts)") { }
-
-        void run()
-        {
-            std::vector<int> v;
-            v.reserve(10000);
-            std::generate_n(std::back_inserter(v), 10000, RandomUpTo(Random(), 10));
-
-            TEST_CHECK_EQUAL(0, *std::min_element(v.begin(), v.end()));
-            TEST_CHECK_EQUAL(9, *std::max_element(v.begin(), v.end()));
-            for (int i(0) ; i < 10 ; ++i)
-            {
-                TEST_CHECK(std::count(v.begin(), v.end(), i) > 1);
-                TEST_CHECK(std::count(v.begin(), v.end(), i) < 3000);
-            }
-        }
-    } test_random_counts;
-
-    /**
-     * \test Test Random distibutions using chi square.
-     *
-     * This is a chi square test, so it could theoretically fail
-     * occasionally. See \ref TaoCP2 3.3.1 for details.
-     */
-    struct RandomDistributionChiSquaredTest : TestCase
-    {
-        RandomDistributionChiSquaredTest() : TestCase("distribution (chi square)") { }
-
-        void run()
-        {
-            int failures(0);
-
-            for (int attempts(0) ; attempts < 3 ; ++ attempts)
-            {
-                std::vector<int> v;
-                v.reserve(10000);
-                std::generate_n(std::back_inserter(v), 10000, RandomUpTo(Random(), 10));
-
-                double a(0);
-                for (int i(0) ; i <= 9 ; ++i)
-                    a += (square(std::count(v.begin(), v.end(), i) - (10000 / 10)) / (10000 / 10));
-
-                TestMessageSuffix suffix("a=" + stringify(a), true);
-                TEST_CHECK(true);
-                if ((a < 2.088) || (a > 21.67))
-                    ++failures;
-            }
-
-            TEST_CHECK(failures <= 1);
-        }
-    } test_random_chi_square;
-}
-