// bdlb_algorithmworkaroundutil.h -*-C++-*-
#ifndef INCLUDED_BDLB_ALGORITHMWORKAROUNDUTIL
#define INCLUDED_BDLB_ALGORITHMWORKAROUNDUTIL
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
//@PURPOSE: Provide a namespace for workarounds for faulty standard algorithms
//
//@CLASSES:
// AlgorithmWorkaroundUtil: namespace for fixed faulty standard algorithms
//
//@SEE_ALSO: std::lower_bound, std::upper_bound
//
//@DESCRIPTION: This component provides a 'struct' namespace for replacement
// workarounds for some platform supplied faulty algorithms (particularly for
// the Sun Studio compiler).
//
///Usage
///-----
// Suppose that we
#include <bdlscm_version.h>
#include <bsls_libraryfeatures.h>
#include <bsls_platform.h>
#include <bsl_algorithm.h>
#include <bsl_iterator.h>
#ifndef BDE_DONT_ALLOW_TRANSITIVE_INCLUDES
#include <bsls_nativestd.h>
#endif // BDE_DONT_ALLOW_TRANSITIVE_INCLUDES
namespace BloombergLP {
namespace bdlb {
// ==============================
// struct AlgorithmWorkaroundUtil
// ==============================
struct AlgorithmWorkaroundUtil {
// A namespace for replacement workarounds for some platform supplied
// faulty algorithms (particularly for the Sun Studio compiler).
// CLASS METHODS
template<class FORWARD_IT, class TYPE>
static
FORWARD_IT lowerBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value);
// Returns an iterator pointing to the first element in the range
// starting at the specified 'first' iterator and ending immediately
// before the specified 'last' iterator, that is greater than or equal
// to the specified 'value', or 'last' if no such element is found.
// This method works around a deficiency in the STLPort standard
// library that prevents using 'lower_bound' to search for a value of a
// different type than that held in the range being searched (even if
// an appropriate 'operator<' is defined). See DRQS 139734639.
template <class FORWARD_IT, class TYPE, class COMPARE>
static
FORWARD_IT lowerBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value,
COMPARE comp);
// Returns an iterator pointing to the first element in the range
// starting at the specified 'first' iterator and ending immediately
// before the specified 'last' iterator, that is greater than or equal
// to the specified 'value' as determined by the specified 'comp', or
// 'last' if no such element is found. This method works around a
// deficiency in the STLPort standard library that prevents using
// 'lower_bound' to search for a value of a different type than that
// held in the range being searched (even if an appropriate 'operator<'
// is defined). See DRQS 139734639.
template<class FORWARD_IT, class TYPE>
static
FORWARD_IT upperBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value);
// Returns an iterator pointing to the first element in the range
// starting at the specified 'first' iterator and ending immediately
// before the specified 'last' iterator, that is greater than the
// specified 'value', or 'last' if no such element is found. This
// method works around a deficiency in the STLPort standard library
// that prevents using 'upper_bound' to search for a value of a
// different type than that held in the range being searched (even if
// an appropriate 'operator<' is defined). See DRQS 139734639.
template <class FORWARD_IT, class TYPE, class COMPARE>
static
FORWARD_IT upperBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value,
COMPARE comp);
// Returns an iterator pointing to the first element in the range
// starting at the specified 'first' iterator and ending immediately
// before the specified 'last' iterator, that is greater than the
// specified 'value' as determined by the specified 'comp', or 'last'
// if no such element is found. This method works around a deficiency
// in the STLPort standard library that prevents using 'upper_bound' to
// search for a value of a different type than that held in the range
// being searched (even if an appropriate 'operator<' is defined). See
// DRQS 139734639.
};
// ============================================================================
// INLINE FUNCTION DEFINITIONS
// ============================================================================
// ------------------------------
// struct AlgorithmWorkaroundUtil
// ------------------------------
template<class FORWARD_IT, class TYPE>
inline
FORWARD_IT AlgorithmWorkaroundUtil::lowerBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value)
{
#if defined(BSLS_LIBRARYFEATURES_STDCPP_STLPORT) \
&& defined(_STLPORT_VERSION) \
&& (_STLPORT_VERSION <= 0x452)
typedef typename bsl::iterator_traits<FORWARD_IT>::difference_type
difference_type;
difference_type length = bsl::distance(first, last);
while (length > 0) {
difference_type half = length >> 1;
FORWARD_IT it = first;
bsl::advance(it, half);
if (*it < value) {
first = ++it;
length -= half + 1;
}
else {
length = half;
}
}
return first;
#else
return std::lower_bound(first, last, value);
#endif
}
template <class FORWARD_IT, class TYPE, class COMPARE>
inline
FORWARD_IT AlgorithmWorkaroundUtil::lowerBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value,
COMPARE comp)
{
#if defined(BSLS_LIBRARYFEATURES_STDCPP_STLPORT) \
&& defined(_STLPORT_VERSION) \
&& (_STLPORT_VERSION <= 0x452)
typedef typename bsl::iterator_traits<FORWARD_IT>::difference_type
difference_type;
difference_type length = bsl::distance(first, last);
while (length > 0) {
difference_type half = length >> 1;
FORWARD_IT it = first;
bsl::advance(it, half);
if (comp(*it, value)) {
first = ++it;
length -= half + 1;
}
else {
length = half;
}
}
return first;
#else
return std::lower_bound(first, last, value, comp);
#endif
}
template<class FORWARD_IT, class TYPE>
inline
FORWARD_IT AlgorithmWorkaroundUtil::upperBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value)
{
#if defined(BSLS_LIBRARYFEATURES_STDCPP_STLPORT) \
&& defined(_STLPORT_VERSION) \
&& (_STLPORT_VERSION <= 0x452)
typedef typename bsl::iterator_traits<FORWARD_IT>::difference_type
difference_type;
difference_type length = bsl::distance(first, last);
while (length > 0) {
difference_type half = length >> 1;
FORWARD_IT it = first;
bsl::advance(it, half);
if (!(value < *it)) {
first = ++it;
length -= half + 1;
}
else {
length = half;
}
}
return first;
#else
return std::upper_bound(first, last, value);
#endif
}
template <class FORWARD_IT, class TYPE, class COMPARE>
inline
FORWARD_IT AlgorithmWorkaroundUtil::upperBound(FORWARD_IT first,
FORWARD_IT last,
const TYPE& value,
COMPARE comp)
{
#if defined(BSLS_LIBRARYFEATURES_STDCPP_STLPORT) \
&& defined(_STLPORT_VERSION) \
&& (_STLPORT_VERSION <= 0x452)
typedef typename bsl::iterator_traits<FORWARD_IT>::difference_type
difference_type;
difference_type length = bsl::distance(first, last);
while (length > 0) {
difference_type half = length >> 1;
FORWARD_IT it = first;
bsl::advance(it, half);
if (!comp(value, *it)) {
first = ++it;
length -= half + 1;
}
else {
length = half;
}
}
return first;
#else
return std::upper_bound(first, last, value, comp);
#endif
}
} // close package namespace
} // close enterprise namespace
#endif
// ----------------------------------------------------------------------------
// Copyright 2019 Bloomberg Finance L.P.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------- END-OF-FILE ----------------------------------