BIND 10 trac641, updated. f1f8de8ad231b05e58abbc8644d5c7ae5bfd9feb [trac641] Random number generator now throws exceptions on error
BIND 10 source code commits
bind10-changes at lists.isc.org
Tue Mar 15 20:05:10 UTC 2011
The branch, trac641 has been updated
via f1f8de8ad231b05e58abbc8644d5c7ae5bfd9feb (commit)
from 6a34b5430a7e16c10cc08a957fedb46cd45b5bbf (commit)
Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.
- Log -----------------------------------------------------------------
commit f1f8de8ad231b05e58abbc8644d5c7ae5bfd9feb
Author: Stephen Morris <stephen at isc.org>
Date: Tue Mar 15 20:02:28 2011 +0000
[trac641] Random number generator now throws exceptions on error
Previously when compiled without NDEBUG set it did, if a check
failed it called assert(). The tests checks for this using
ASSERT_DEATH. However, ASSERT_DEATH leaks memory and this was
obscuring the valgrind output. The changes here cause an exception
to be thrown (instead of a call to abort()) in the case of an error
and the unit tests now EXPECT_THROW instead of ASSERT_DEATH.
-----------------------------------------------------------------------
Summary of changes:
src/lib/nsas/random_number_generator.h | 73 ++++++++++++++++----
.../nsas/tests/random_number_generator_unittest.cc | 16 +++--
2 files changed, 69 insertions(+), 20 deletions(-)
-----------------------------------------------------------------------
diff --git a/src/lib/nsas/random_number_generator.h b/src/lib/nsas/random_number_generator.h
index e80ebcb..85c6b89 100644
--- a/src/lib/nsas/random_number_generator.h
+++ b/src/lib/nsas/random_number_generator.h
@@ -15,8 +15,12 @@
#ifndef __NSAS_RANDOM_NUMBER_GENERATOR_H
#define __NSAS_RANDOM_NUMBER_GENERATOR_H
+#include <algorithm>
#include <cmath>
#include <numeric>
+
+#include <exceptions/exceptions.h>
+
#include <boost/random/mersenne_twister.hpp>
#include <boost/random/uniform_int.hpp>
#include <boost/random/uniform_real.hpp>
@@ -25,6 +29,26 @@
namespace isc {
namespace nsas {
+class InvalidLimits : public Exception {
+public:
+ InvalidLimits(const char* file, size_t line, const char* what) :
+ isc::Exception(file, line, what) {}
+};
+
+class SumNotOne : public Exception {
+public:
+ SumNotOne(const char* file, size_t line, const char* what) :
+ isc::Exception(file, line, what) {}
+};
+
+class InvalidProbValue : public Exception {
+public:
+ InvalidProbValue(const char* file, size_t line, const char* what) :
+ isc::Exception(file, line, what) {}
+};
+
+
+
/// \brief Uniform random integer generator
///
/// Generate uniformly distributed integers in range of [min, max]
@@ -35,8 +59,17 @@ public:
/// \param min The minimum number in the range
/// \param max The maximum number in the range
UniformRandomIntegerGenerator(int min, int max):
- min_(min), max_(max), dist_(min, max), generator_(rng_, dist_)
+ min_(std::min(min, max)), max_(std::max(min, max)),
+ dist_(min_, max_), generator_(rng_, dist_)
{
+ // To preserve the restriction of the underlying uniform_int class (and
+ // to retain compatibility with earlier versions of the class), we will
+ // abort if the minimum and maximum given are the wrong way round.
+ if (min > max) {
+ isc_throw(InvalidLimits, "minimum limit is greater than maximum "
+ "when initializing UniformRandomIntegerGenerator");
+ }
+
// Init with the current time
rng_.seed(time(NULL));
}
@@ -73,8 +106,10 @@ public:
size_t min = 0):
dist_(0, 1.0), uniform_real_gen_(rng_, dist_), min_(min)
{
- // The probabilities must be valid
- assert(isProbabilitiesValid(probabilities));
+ // The probabilities must be valid. Checking is quite an expensive
+ // operation, so is only done in a debug build.
+ assert(areProbabilitiesValid(probabilities));
+
// Calculate the partial sum of probabilities
std::partial_sum(probabilities.begin(), probabilities.end(),
std::back_inserter(cumulative_));
@@ -96,8 +131,8 @@ public:
/// \param min The minimum integer that generated
void reset(const std::vector<double>& probabilities, size_t min = 0)
{
- // The probabilities must be valid
- assert(isProbabilitiesValid(probabilities));
+ // The probabilities must be valid.
+ assert(areProbabilitiesValid(probabilities));
// Reset the cumulative sum
cumulative_.clear();
@@ -120,16 +155,24 @@ public:
private:
/// \brief Check the validation of probabilities vector
///
- /// The probability must be in range of [0, 1.0] and the sum must be equal to 1.0
- /// Empty probabilities is also valid.
- bool isProbabilitiesValid(const std::vector<double>& probabilities) const
+ /// The probability must be in range of [0, 1.0] and the sum must be equal
+ /// to 1.0. Empty probabilities are also valid.
+ ///
+ /// Checking the probabilities is quite an expensive operation, so it is
+ /// only done during a debug build (via a call through assert()). However,
+ /// instead of letting assert() call abort(), if this method encounters an
+ /// error, an exception is thrown. This makes unit testing somewhat easier.
+ ///
+ /// \param probabilities Vector of probabilities.
+ bool areProbabilitiesValid(const std::vector<double>& probabilities) const
{
typedef std::vector<double>::const_iterator Iterator;
double sum = probabilities.empty() ? 1.0 : 0.0;
for(Iterator it = probabilities.begin(); it != probabilities.end(); ++it){
//The probability must be in [0, 1.0]
if(*it < 0.0 || *it > 1.0) {
- return false;
+ isc_throw(InvalidProbValue,
+ "probability must be in the range 0..1");
}
sum += *it;
@@ -137,12 +180,16 @@ private:
double epsilon = 0.0001;
// The sum must be equal to 1
- return std::fabs(sum - 1.0) < epsilon;
+ if (std::fabs(sum - 1.0) >= epsilon) {
+ isc_throw(SumNotOne, "Sum of probabilities is not equal to 1");
+ }
+
+ return true;
}
- std::vector<double> cumulative_; ///< The partial sum of the probabilities
- boost::mt19937 rng_; ///< Mersenne Twister: A 623-dimensionally equidistributed uniform pseudo-random number generator
- boost::uniform_real<> dist_; ///< Uniformly distributed real numbers
+ std::vector<double> cumulative_; ///< Partial sum of the probabilities
+ boost::mt19937 rng_; ///< Mersenne Twister: A 623-dimensionally equidistributed uniform pseudo-random number generator
+ boost::uniform_real<> dist_; ///< Uniformly distributed real numbers
// Shortcut typedef
// This typedef is placed directly before its use, as the sunstudio
diff --git a/src/lib/nsas/tests/random_number_generator_unittest.cc b/src/lib/nsas/tests/random_number_generator_unittest.cc
index c306b09..85cbcbf 100644
--- a/src/lib/nsas/tests/random_number_generator_unittest.cc
+++ b/src/lib/nsas/tests/random_number_generator_unittest.cc
@@ -59,11 +59,11 @@ private:
// non-debug environment.
// Note: the death test is not supported by all platforms. We need to
// compile tests using it selectively.
-#if !defined(NDEBUG) && defined(GTEST_HAS_DEATH_TEST)
+#if !defined(NDEBUG)
// Test of the constructor
TEST_F(UniformRandomIntegerGeneratorTest, Constructor) {
// The range must be min<=max
- ASSERT_DEATH(UniformRandomIntegerGenerator(3, 2), "");
+ ASSERT_THROW(UniformRandomIntegerGenerator(3, 2), InvalidLimits);
}
#endif
@@ -109,30 +109,32 @@ TEST_F(WeightedRandomIntegerGeneratorTest, Constructor) {
/// the tests will be failed since assert() is non-op in non-debug version.
/// The "#ifndef NDEBUG" is added to make the tests be performed only in
/// non-debug environment.
-#if !defined(NDEBUG) && defined(GTEST_HAS_DEATH_TEST)
+#if !defined(NDEBUG)
//The probability must be >= 0
probabilities.push_back(-0.1);
probabilities.push_back(1.1);
- ASSERT_DEATH(WeightedRandomIntegerGenerator gen2(probabilities), "");
+ ASSERT_THROW(WeightedRandomIntegerGenerator gen2(probabilities),
+ InvalidProbValue);
//The probability must be <= 1.0
probabilities.clear();
probabilities.push_back(0.1);
probabilities.push_back(1.1);
- ASSERT_DEATH(WeightedRandomIntegerGenerator gen3(probabilities), "");
+ ASSERT_THROW(WeightedRandomIntegerGenerator gen3(probabilities),
+ InvalidProbValue);
//The sum must be equal to 1.0
probabilities.clear();
probabilities.push_back(0.2);
probabilities.push_back(0.9);
- ASSERT_DEATH(WeightedRandomIntegerGenerator gen4(probabilities), "");
+ ASSERT_THROW(WeightedRandomIntegerGenerator gen4(probabilities), SumNotOne);
//The sum must be equal to 1.0
probabilities.clear();
probabilities.push_back(0.3);
probabilities.push_back(0.2);
probabilities.push_back(0.1);
- ASSERT_DEATH(WeightedRandomIntegerGenerator gen5(probabilities), "");
+ ASSERT_THROW(WeightedRandomIntegerGenerator gen5(probabilities), SumNotOne);
#endif
}
More information about the bind10-changes
mailing list