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/////////////////////////////////////////////////////////////////////////// |
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// |
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// Copyright (c) 2009, Industrial Light & Magic, a division of Lucas |
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// Digital Ltd. LLC |
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// |
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// All rights reserved. |
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// |
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// Redistribution and use in source and binary forms, with or without |
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// modification, are permitted provided that the following conditions are |
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// met: |
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// * Redistributions of source code must retain the above copyright |
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// notice, this list of conditions and the following disclaimer. |
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// * Redistributions in binary form must reproduce the above |
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// copyright notice, this list of conditions and the following disclaimer |
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// in the documentation and/or other materials provided with the |
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// distribution. |
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// * Neither the name of Industrial Light & Magic nor the names of |
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// its contributors may be used to endorse or promote products derived |
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// from this software without specific prior written permission. |
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// |
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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// |
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/////////////////////////////////////////////////////////////////////////// |
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|
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#ifndef INCLUDED_IMF_CHECKED_ARITHMETIC_H |
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#define INCLUDED_IMF_CHECKED_ARITHMETIC_H |
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|
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//----------------------------------------------------------------------------- |
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// |
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// Integer arithmetic operations that throw exceptions |
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// on overflow, underflow or division by zero. |
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// |
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//----------------------------------------------------------------------------- |
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|
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#include <limits> |
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#include <IexMathExc.h> |
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|
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namespace Imf { |
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|
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template <bool b> struct StaticAssertionFailed; |
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template <> struct StaticAssertionFailed <true> {}; |
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|
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#define IMF_STATIC_ASSERT(x) \ |
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do {StaticAssertionFailed <x> staticAssertionFailed;} while (false) |
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|
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|
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template <class T> |
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T |
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uiMult (T a, T b) |
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{ |
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// |
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// Unsigned integer multiplication |
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// |
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|
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IMF_STATIC_ASSERT (!std::numeric_limits<T>::is_signed && |
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std::numeric_limits<T>::is_integer); |
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|
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if (a > 0 && b > std::numeric_limits<T>::max() / a) |
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throw Iex::OverflowExc ("Integer multiplication overflow."); |
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|
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return a * b; |
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} |
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|
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|
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template <class T> |
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T |
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uiDiv (T a, T b) |
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{ |
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// |
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// Unsigned integer division |
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// |
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|
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IMF_STATIC_ASSERT (!std::numeric_limits<T>::is_signed && |
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std::numeric_limits<T>::is_integer); |
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|
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if (b == 0) |
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throw Iex::DivzeroExc ("Integer division by zero."); |
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|
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return a / b; |
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} |
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|
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|
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template <class T> |
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T |
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uiAdd (T a, T b) |
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{ |
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// |
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// Unsigned integer addition |
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// |
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|
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IMF_STATIC_ASSERT (!std::numeric_limits<T>::is_signed && |
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std::numeric_limits<T>::is_integer); |
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|
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if (a > std::numeric_limits<T>::max() - b) |
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throw Iex::OverflowExc ("Integer addition overflow."); |
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|
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return a + b; |
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} |
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|
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|
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template <class T> |
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T |
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uiSub (T a, T b) |
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{ |
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// |
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// Unsigned integer subtraction |
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// |
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|
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IMF_STATIC_ASSERT (!std::numeric_limits<T>::is_signed && |
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std::numeric_limits<T>::is_integer); |
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|
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if (a < b) |
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throw Iex::UnderflowExc ("Integer subtraction underflow."); |
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|
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return a - b; |
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} |
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|
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|
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template <class T> |
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size_t |
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checkArraySize (T n, size_t s) |
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{ |
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// |
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// Verify that the size, in bytes, of an array with n elements |
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// of size s can be computed without overflowing: |
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// |
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// If computing |
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// |
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// size_t (n) * s |
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// |
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// would overflow, then throw an Iex::OverflowExc exception. |
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// Otherwise return |
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// |
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// size_t (n). |
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// |
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|
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IMF_STATIC_ASSERT (!std::numeric_limits<T>::is_signed && |
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std::numeric_limits<T>::is_integer); |
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|
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IMF_STATIC_ASSERT (sizeof (T) <= sizeof (size_t)); |
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|
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if (size_t (n) > std::numeric_limits<size_t>::max() / s) |
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throw Iex::OverflowExc ("Integer multiplication overflow."); |
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|
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return size_t (n); |
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} |
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|
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|
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} // namespace Imf |
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|
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#endif |