| #ifndef LIBGAV1_SRC_UTILS_ARRAY_2D_H_ |
| #define LIBGAV1_SRC_UTILS_ARRAY_2D_H_ |
| |
| #include <cstddef> |
| #include <cstring> |
| #include <memory> |
| #include <new> |
| #include <type_traits> |
| |
| #include "src/utils/compiler_attributes.h" |
| |
| namespace libgav1 { |
| |
| // Exposes a 1D allocated memory buffer as a 2D array. |
| template <typename T> |
| class Array2DView { |
| public: |
| Array2DView() = default; |
| Array2DView(int rows, int columns, T* const data) { |
| Reset(rows, columns, data); |
| } |
| |
| // Copyable and Movable. |
| Array2DView(const Array2DView& rhs) = default; |
| Array2DView& operator=(const Array2DView& rhs) = default; |
| |
| void Reset(int rows, int columns, T* const data) { |
| rows_ = rows; |
| columns_ = columns; |
| data_ = data; |
| } |
| |
| int rows() const { return rows_; } |
| int columns() const { return columns_; } |
| |
| T* operator[](int row) { return const_cast<T*>(GetRow(row)); } |
| |
| const T* operator[](int row) const { return GetRow(row); } |
| |
| private: |
| const T* GetRow(int row) const { |
| const ptrdiff_t offset = static_cast<ptrdiff_t>(row) * columns_; |
| return (row < rows_) ? data_ + offset : nullptr; |
| } |
| |
| int rows_ = 0; |
| int columns_ = 0; |
| T* data_ = nullptr; |
| }; |
| |
| // Allocates and owns the contiguous memory and exposes an Array2DView of |
| // dimension |rows| x |columns|. |
| template <typename T> |
| class Array2D { |
| public: |
| Array2D() = default; |
| |
| // Copyable and Movable. |
| Array2D(const Array2D& rhs) = default; |
| Array2D& operator=(const Array2D& rhs) = default; |
| |
| LIBGAV1_MUST_USE_RESULT bool Reset(int rows, int columns, |
| bool zero_initialize = true) { |
| const size_t size = rows * columns; |
| // If T is not a trivial type, we should always reallocate the data_ |
| // buffer, so that the destructors of any existing objects are invoked. |
| if (!std::is_trivial<T>::value || size_ < size) { |
| // Note: This invokes the global operator new if T is a non-class type, |
| // such as integer or enum types, or a class type that is not derived |
| // from libgav1::Allocable, such as std::unique_ptr. If we enforce a |
| // maximum allocation size or keep track of our own heap memory |
| // consumption, we will need to handle the allocations here that use the |
| // global operator new. |
| if (zero_initialize) { |
| data_.reset(new (std::nothrow) T[size]()); |
| } else { |
| data_.reset(new (std::nothrow) T[size]); |
| } |
| if (data_ == nullptr) { |
| size_ = 0; |
| return false; |
| } |
| size_ = size; |
| } else if (zero_initialize) { |
| // Cast the data_ pointer to void* to avoid the GCC -Wclass-memaccess |
| // warning. The memset is safe because T is a trivial type. |
| void* dest = data_.get(); |
| memset(dest, 0, sizeof(T) * size); |
| } |
| data_view_.Reset(rows, columns, data_.get()); |
| return true; |
| } |
| |
| int rows() const { return data_view_.rows(); } |
| int columns() const { return data_view_.columns(); } |
| T* data() { return data_.get(); } |
| |
| T* operator[](int row) { return data_view_[row]; } |
| |
| const T* operator[](int row) const { return data_view_[row]; } |
| |
| private: |
| std::unique_ptr<T[]> data_ = nullptr; |
| size_t size_ = 0; |
| Array2DView<T> data_view_; |
| }; |
| |
| } // namespace libgav1 |
| |
| #endif // LIBGAV1_SRC_UTILS_ARRAY_2D_H_ |