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Diffstat (limited to 'extra/yassl/taocrypt/include/block.hpp')
| -rw-r--r-- | extra/yassl/taocrypt/include/block.hpp | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/extra/yassl/taocrypt/include/block.hpp b/extra/yassl/taocrypt/include/block.hpp new file mode 100644 index 00000000000..6e96ec9cc35 --- /dev/null +++ b/extra/yassl/taocrypt/include/block.hpp @@ -0,0 +1,211 @@ +/* block.hpp + * + * Copyright (C) 2003 Sawtooth Consulting Ltd. + * + * This file is part of yaSSL. + * + * yaSSL is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * yaSSL 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 + */ + + +/* block.hpp provides word and byte blocks with configurable allocators +*/ + + +#ifndef TAO_CRYPT_BLOCK_HPP +#define TAO_CRYPT_BLOCK_HPP + +#include "algorithm.hpp" // mySTL::swap +#include "stdexcept.hpp" // mySTL::runtime_error +#include "misc.hpp" +#include <string.h> // memcpy +#include <cstddef> // ptrdiff_t + + +#if defined(_MSC_VER) && defined(_CRTAPI1) +#define TAOCRYPT_MSVCRT6 +#endif + + +namespace TaoCrypt { + + +// a Base class for Allocators +template<class T> +class AllocatorBase +{ +public: + typedef T value_type; + typedef size_t size_type; +#ifdef TAOCRYPT_MSVCRT6 + typedef ptrdiff_t difference_type; +#else + typedef std::ptrdiff_t difference_type; +#endif + typedef T* pointer; + typedef const T* const_pointer; + typedef T& reference; + typedef const T& const_reference; + + pointer address(reference r) const {return (&r);} + const_pointer address(const_reference r) const {return (&r); } + void construct(pointer p, const T& val) {new (p) T(val);} + void destroy(pointer p) {p->~T();} + size_type max_size() const {return ~size_type(0)/sizeof(T);} +protected: + static void CheckSize(size_t n) + { + assert(n <= ~size_t(0) / sizeof(T)); + } +}; + + +// General purpose realloc +template<typename T, class A> +typename A::pointer StdReallocate(A& a, T* p, typename A::size_type oldSize, + typename A::size_type newSize, bool preserve) +{ + if (oldSize == newSize) + return p; + + if (preserve) { + A b = A(); + typename A::pointer newPointer = b.allocate(newSize, 0); + memcpy(newPointer, p, sizeof(T) * min(oldSize, newSize)); + a.deallocate(p, oldSize); + mySTL::swap(a, b); + return newPointer; + } + else { + a.deallocate(p, oldSize); + return a.allocate(newSize, 0); + } +} + + +// Allocator that zeros out memory on deletion +template <class T> +class AllocatorWithCleanup : public AllocatorBase<T> +{ +public: + typedef typename AllocatorBase<T>::pointer pointer; + typedef typename AllocatorBase<T>::size_type size_type; + + pointer allocate(size_type n, const void* = 0) + { + CheckSize(n); + if (n == 0) + return 0; + return new (tc) T[n]; + } + + void deallocate(void* p, size_type n) + { + memset(p, 0, n * sizeof(T)); + delete [] (T*)p; + } + + pointer reallocate(T* p, size_type oldSize, size_type newSize, + bool preserve) + { + return StdReallocate(*this, p, oldSize, newSize, preserve); + } + + // VS.NET STL enforces the policy of "All STL-compliant allocators have to + // provide a template class member called rebind". + template <class U> struct rebind { typedef AllocatorWithCleanup<U> other;}; +}; + + +// Block class template +template<typename T, class A = AllocatorWithCleanup<T> > +class Block { +public: + explicit Block(word32 s = 0) : sz_(s), buffer_(allocator_.allocate(sz_)) + { CleanNew(sz_); } + + Block(const T* buff, word32 s) : sz_(s), buffer_(allocator_.allocate(sz_)) + { memcpy(buffer_, buff, sz_ * sizeof(T)); } + + Block(const Block& that) : sz_(that.sz_), buffer_(allocator_.allocate(sz_)) + { memcpy(buffer_, that.buffer_, sz_ * sizeof(T)); } + + Block& operator=(const Block& that) { + Block tmp(that); + Swap(tmp); + return *this; + } + + T& operator[] (word32 i) { assert(i < sz_); return buffer_[i]; } + const T& operator[] (word32 i) const + { assert(i < sz_); return buffer_[i]; } + + T* operator+ (word32 i) { return buffer_ + i; } + const T* operator+ (word32 i) const { return buffer_ + i; } + + word32 size() const { return sz_; } + + T* get_buffer() const { return buffer_; } + T* begin() const { return get_buffer(); } + + void CleanGrow(word32 newSize) + { + if (newSize > sz_) { + buffer_ = allocator_.reallocate(buffer_, sz_, newSize, true); + memset(buffer_ + sz_, 0, (newSize - sz_) * sizeof(T)); + sz_ = newSize; + } + } + + void CleanNew(word32 newSize) + { + New(newSize); + memset(buffer_, 0, sz_ * sizeof(T)); + } + + void New(word32 newSize) + { + buffer_ = allocator_.reallocate(buffer_, sz_, newSize, false); + sz_ = newSize; + } + + void resize(word32 newSize) + { + buffer_ = allocator_.reallocate(buffer_, sz_, newSize, true); + sz_ = newSize; + } + + void Swap(Block& other) { + mySTL::swap(sz_, other.sz_); + mySTL::swap(buffer_, other.buffer_); + mySTL::swap(allocator_, other.allocator_); + } + + ~Block() { allocator_.deallocate(buffer_, sz_); } +private: + word32 sz_; // size in Ts + T* buffer_; + A allocator_; +}; + + +typedef Block<byte> ByteBlock; +typedef Block<word> WordBlock; +typedef Block<word32> Word32Block; + + +} // namespace + +#endif // TAO_CRYPT_BLOCK_HPP |