| Index: base/stack_container.h
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| diff --git a/base/stack_container.h b/base/stack_container.h
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| deleted file mode 100644
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| index c5897836db96b163d144121e4337ca190476523d..0000000000000000000000000000000000000000
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| --- a/base/stack_container.h
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| +++ /dev/null
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| @@ -1,251 +0,0 @@
|
| -// Copyright (c) 2012 The Chromium Authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -#ifndef BASE_STACK_CONTAINER_H_
|
| -#define BASE_STACK_CONTAINER_H_
|
| -
|
| -#include <string>
|
| -#include <vector>
|
| -
|
| -#include "base/basictypes.h"
|
| -#include "build/build_config.h"
|
| -#include "base/memory/aligned_memory.h"
|
| -
|
| -// This allocator can be used with STL containers to provide a stack buffer
|
| -// from which to allocate memory and overflows onto the heap. This stack buffer
|
| -// would be allocated on the stack and allows us to avoid heap operations in
|
| -// some situations.
|
| -//
|
| -// STL likes to make copies of allocators, so the allocator itself can't hold
|
| -// the data. Instead, we make the creator responsible for creating a
|
| -// StackAllocator::Source which contains the data. Copying the allocator
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| -// merely copies the pointer to this shared source, so all allocators created
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| -// based on our allocator will share the same stack buffer.
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| -//
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| -// This stack buffer implementation is very simple. The first allocation that
|
| -// fits in the stack buffer will use the stack buffer. Any subsequent
|
| -// allocations will not use the stack buffer, even if there is unused room.
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| -// This makes it appropriate for array-like containers, but the caller should
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| -// be sure to reserve() in the container up to the stack buffer size. Otherwise
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| -// the container will allocate a small array which will "use up" the stack
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| -// buffer.
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| -template<typename T, size_t stack_capacity>
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| -class StackAllocator : public std::allocator<T> {
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| - public:
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| - typedef typename std::allocator<T>::pointer pointer;
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| - typedef typename std::allocator<T>::size_type size_type;
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| -
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| - // Backing store for the allocator. The container owner is responsible for
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| - // maintaining this for as long as any containers using this allocator are
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| - // live.
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| - struct Source {
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| - Source() : used_stack_buffer_(false) {
|
| - }
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| -
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| - // Casts the buffer in its right type.
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| - T* stack_buffer() { return stack_buffer_.template data_as<T>(); }
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| - const T* stack_buffer() const {
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| - return stack_buffer_.template data_as<T>();
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| - }
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| -
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| - // The buffer itself. It is not of type T because we don't want the
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| - // constructors and destructors to be automatically called. Define a POD
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| - // buffer of the right size instead.
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| - base::AlignedMemory<sizeof(T[stack_capacity]), ALIGNOF(T)> stack_buffer_;
|
| -#if defined(OS_ANDROID)
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| - COMPILE_ASSERT(ALIGNOF(T) <= 16, crbug_115612);
|
| -#endif
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| -
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| - // Set when the stack buffer is used for an allocation. We do not track
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| - // how much of the buffer is used, only that somebody is using it.
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| - bool used_stack_buffer_;
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| - };
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| -
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| - // Used by containers when they want to refer to an allocator of type U.
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| - template<typename U>
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| - struct rebind {
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| - typedef StackAllocator<U, stack_capacity> other;
|
| - };
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| -
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| - // For the straight up copy c-tor, we can share storage.
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| - StackAllocator(const StackAllocator<T, stack_capacity>& rhs)
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| - : std::allocator<T>(), source_(rhs.source_) {
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| - }
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| -
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| - // ISO C++ requires the following constructor to be defined,
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| - // and std::vector in VC++2008SP1 Release fails with an error
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| - // in the class _Container_base_aux_alloc_real (from <xutility>)
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| - // if the constructor does not exist.
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| - // For this constructor, we cannot share storage; there's
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| - // no guarantee that the Source buffer of Ts is large enough
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| - // for Us.
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| - // TODO: If we were fancy pants, perhaps we could share storage
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| - // iff sizeof(T) == sizeof(U).
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| - template<typename U, size_t other_capacity>
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| - StackAllocator(const StackAllocator<U, other_capacity>& other)
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| - : source_(NULL) {
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| - }
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| -
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| - explicit StackAllocator(Source* source) : source_(source) {
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| - }
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| -
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| - // Actually do the allocation. Use the stack buffer if nobody has used it yet
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| - // and the size requested fits. Otherwise, fall through to the standard
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| - // allocator.
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| - pointer allocate(size_type n, void* hint = 0) {
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| - if (source_ != NULL && !source_->used_stack_buffer_
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| - && n <= stack_capacity) {
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| - source_->used_stack_buffer_ = true;
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| - return source_->stack_buffer();
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| - } else {
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| - return std::allocator<T>::allocate(n, hint);
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| - }
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| - }
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| -
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| - // Free: when trying to free the stack buffer, just mark it as free. For
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| - // non-stack-buffer pointers, just fall though to the standard allocator.
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| - void deallocate(pointer p, size_type n) {
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| - if (source_ != NULL && p == source_->stack_buffer())
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| - source_->used_stack_buffer_ = false;
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| - else
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| - std::allocator<T>::deallocate(p, n);
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| - }
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| -
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| - private:
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| - Source* source_;
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| -};
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| -
|
| -// A wrapper around STL containers that maintains a stack-sized buffer that the
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| -// initial capacity of the vector is based on. Growing the container beyond the
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| -// stack capacity will transparently overflow onto the heap. The container must
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| -// support reserve().
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| -//
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| -// WATCH OUT: the ContainerType MUST use the proper StackAllocator for this
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| -// type. This object is really intended to be used only internally. You'll want
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| -// to use the wrappers below for different types.
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| -template<typename TContainerType, int stack_capacity>
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| -class StackContainer {
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| - public:
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| - typedef TContainerType ContainerType;
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| - typedef typename ContainerType::value_type ContainedType;
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| - typedef StackAllocator<ContainedType, stack_capacity> Allocator;
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| -
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| - // Allocator must be constructed before the container!
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| - StackContainer() : allocator_(&stack_data_), container_(allocator_) {
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| - // Make the container use the stack allocation by reserving our buffer size
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| - // before doing anything else.
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| - container_.reserve(stack_capacity);
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| - }
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| -
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| - // Getters for the actual container.
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| - //
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| - // Danger: any copies of this made using the copy constructor must have
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| - // shorter lifetimes than the source. The copy will share the same allocator
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| - // and therefore the same stack buffer as the original. Use std::copy to
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| - // copy into a "real" container for longer-lived objects.
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| - ContainerType& container() { return container_; }
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| - const ContainerType& container() const { return container_; }
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| -
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| - // Support operator-> to get to the container. This allows nicer syntax like:
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| - // StackContainer<...> foo;
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| - // std::sort(foo->begin(), foo->end());
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| - ContainerType* operator->() { return &container_; }
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| - const ContainerType* operator->() const { return &container_; }
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| -
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| -#ifdef UNIT_TEST
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| - // Retrieves the stack source so that that unit tests can verify that the
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| - // buffer is being used properly.
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| - const typename Allocator::Source& stack_data() const {
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| - return stack_data_;
|
| - }
|
| -#endif
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| -
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| - protected:
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| - typename Allocator::Source stack_data_;
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| - Allocator allocator_;
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| - ContainerType container_;
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| -
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| - DISALLOW_COPY_AND_ASSIGN(StackContainer);
|
| -};
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| -
|
| -// StackString
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| -template<size_t stack_capacity>
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| -class StackString : public StackContainer<
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| - std::basic_string<char,
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| - std::char_traits<char>,
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| - StackAllocator<char, stack_capacity> >,
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| - stack_capacity> {
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| - public:
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| - StackString() : StackContainer<
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| - std::basic_string<char,
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| - std::char_traits<char>,
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| - StackAllocator<char, stack_capacity> >,
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| - stack_capacity>() {
|
| - }
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| -
|
| - private:
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| - DISALLOW_COPY_AND_ASSIGN(StackString);
|
| -};
|
| -
|
| -// StackWString
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| -template<size_t stack_capacity>
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| -class StackWString : public StackContainer<
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| - std::basic_string<wchar_t,
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| - std::char_traits<wchar_t>,
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| - StackAllocator<wchar_t, stack_capacity> >,
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| - stack_capacity> {
|
| - public:
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| - StackWString() : StackContainer<
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| - std::basic_string<wchar_t,
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| - std::char_traits<wchar_t>,
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| - StackAllocator<wchar_t, stack_capacity> >,
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| - stack_capacity>() {
|
| - }
|
| -
|
| - private:
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| - DISALLOW_COPY_AND_ASSIGN(StackWString);
|
| -};
|
| -
|
| -// StackVector
|
| -//
|
| -// Example:
|
| -// StackVector<int, 16> foo;
|
| -// foo->push_back(22); // we have overloaded operator->
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| -// foo[0] = 10; // as well as operator[]
|
| -template<typename T, size_t stack_capacity>
|
| -class StackVector : public StackContainer<
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| - std::vector<T, StackAllocator<T, stack_capacity> >,
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| - stack_capacity> {
|
| - public:
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| - StackVector() : StackContainer<
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| - std::vector<T, StackAllocator<T, stack_capacity> >,
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| - stack_capacity>() {
|
| - }
|
| -
|
| - // We need to put this in STL containers sometimes, which requires a copy
|
| - // constructor. We can't call the regular copy constructor because that will
|
| - // take the stack buffer from the original. Here, we create an empty object
|
| - // and make a stack buffer of its own.
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| - StackVector(const StackVector<T, stack_capacity>& other)
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| - : StackContainer<
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| - std::vector<T, StackAllocator<T, stack_capacity> >,
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| - stack_capacity>() {
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| - this->container().assign(other->begin(), other->end());
|
| - }
|
| -
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| - StackVector<T, stack_capacity>& operator=(
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| - const StackVector<T, stack_capacity>& other) {
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| - this->container().assign(other->begin(), other->end());
|
| - return *this;
|
| - }
|
| -
|
| - // Vectors are commonly indexed, which isn't very convenient even with
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| - // operator-> (using "->at()" does exception stuff we don't want).
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| - T& operator[](size_t i) { return this->container().operator[](i); }
|
| - const T& operator[](size_t i) const {
|
| - return this->container().operator[](i);
|
| - }
|
| -};
|
| -
|
| -#endif // BASE_STACK_CONTAINER_H_
|
|
|