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/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program 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.
*
* This program 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef COMMON_ARRAY_H
#define COMMON_ARRAY_H
#include "common/scummsys.h"
#include "common/algorithm.h"
#include "common/textconsole.h" // For error()
#include "common/memory.h"
namespace Common {
/**
* This class implements a dynamically sized container, which
* can be accessed similar to a regular C++ array. Accessing
* elements is performed in constant time (like with plain arrays).
* In addition, one can append, insert and remove entries (this
* is the 'dynamic' part). Doing that in general takes time
* proportional to the number of elements in the array.
*
* The container class closest to this in the C++ standard library is
* std::vector. However, there are some differences.
*/
template<class T>
class Array {
public:
typedef T *iterator;
typedef const T *const_iterator;
typedef T value_type;
typedef uint size_type;
protected:
size_type _capacity;
size_type _size;
T *_storage;
public:
Array() : _capacity(0), _size(0), _storage(0) {}
Array(const Array<T> &array) : _capacity(array._size), _size(array._size), _storage(0) {
if (array._storage) {
allocCapacity(_size);
uninitialized_copy(array._storage, array._storage + _size, _storage);
}
}
/**
* Construct an array by copying data from a regular array.
*/
template<class T2>
Array(const T2 *data, size_type n) {
_size = n;
allocCapacity(n);
uninitialized_copy(data, data + _size, _storage);
}
~Array() {
freeStorage(_storage, _size);
_storage = 0;
_capacity = _size = 0;
}
/** Appends element to the end of the array. */
void push_back(const T &element) {
if (_size + 1 <= _capacity)
new ((void *)&_storage[_size++]) T(element);
else
insert_aux(end(), &element, &element + 1);
}
void push_back(const Array<T> &array) {
if (_size + array.size() <= _capacity) {
uninitialized_copy(array.begin(), array.end(), end());
_size += array.size();
} else
insert_aux(end(), array.begin(), array.end());
}
/** Removes the last element of the array. */
void pop_back() {
assert(_size > 0);
_size--;
// We also need to destroy the last object properly here.
_storage[_size].~T();
}
/** Returns a reference to the first element of the array. */
T &front() {
assert(_size > 0);
return _storage[0];
}
/** Returns a reference to the first element of the array. */
const T &front() const {
assert(_size > 0);
return _storage[0];
}
/** Returns a reference to the last element of the array. */
T &back() {
assert(_size > 0);
return _storage[_size-1];
}
/** Returns a reference to the last element of the array. */
const T &back() const {
assert(_size > 0);
return _storage[_size-1];
}
void insert_at(size_type idx, const T &element) {
assert(idx <= _size);
insert_aux(_storage + idx, &element, &element + 1);
}
void insert_at(size_type idx, const Array<T> &array) {
assert(idx <= _size);
insert_aux(_storage + idx, array.begin(), array.end());
}
/**
* Inserts element before pos.
*/
void insert(iterator pos, const T &element) {
insert_aux(pos, &element, &element + 1);
}
T remove_at(size_type idx) {
assert(idx < _size);
T tmp = _storage[idx];
copy(_storage + idx + 1, _storage + _size, _storage + idx);
_size--;
// We also need to destroy the last object properly here.
_storage[_size].~T();
return tmp;
}
// TODO: insert, remove, ...
T &operator[](size_type idx) {
assert(idx < _size);
return _storage[idx];
}
const T &operator[](size_type idx) const {
assert(idx < _size);
return _storage[idx];
}
Array<T> &operator=(const Array<T> &array) {
if (this == &array)
return *this;
freeStorage(_storage, _size);
_size = array._size;
allocCapacity(_size);
uninitialized_copy(array._storage, array._storage + _size, _storage);
return *this;
}
size_type size() const {
return _size;
}
void clear() {
freeStorage(_storage, _size);
_storage = 0;
_size = 0;
_capacity = 0;
}
iterator erase(iterator pos) {
copy(pos + 1, _storage + _size, pos);
_size--;
// We also need to destroy the last object properly here.
_storage[_size].~T();
return pos;
}
bool empty() const {
return (_size == 0);
}
bool operator==(const Array<T> &other) const {
if (this == &other)
return true;
if (_size != other._size)
return false;
for (size_type i = 0; i < _size; ++i) {
if (_storage[i] != other._storage[i])
return false;
}
return true;
}
bool operator!=(const Array<T> &other) const {
return !(*this == other);
}
iterator begin() {
return _storage;
}
iterator end() {
return _storage + _size;
}
const_iterator begin() const {
return _storage;
}
const_iterator end() const {
return _storage + _size;
}
void reserve(size_type newCapacity) {
if (newCapacity <= _capacity)
return;
T *oldStorage = _storage;
allocCapacity(newCapacity);
if (oldStorage) {
// Copy old data
uninitialized_copy(oldStorage, oldStorage + _size, _storage);
freeStorage(oldStorage, _size);
}
}
void resize(size_type newSize) {
reserve(newSize);
for (size_type i = _size; i < newSize; ++i)
new ((void *)&_storage[i]) T();
_size = newSize;
}
void assign(const_iterator first, const_iterator last) {
resize(distance(first, last)); // FIXME: ineffective?
T *dst = _storage;
while (first != last)
*dst++ = *first++;
}
protected:
static size_type roundUpCapacity(size_type capacity) {
// Round up capacity to the next power of 2;
// we use a minimal capacity of 8.
size_type capa = 8;
while (capa < capacity)
capa <<= 1;
return capa;
}
void allocCapacity(size_type capacity) {
_capacity = capacity;
if (capacity) {
_storage = (T *)malloc(sizeof(T) * capacity);
if (!_storage)
::error("Common::Array: failure to allocate %u bytes", capacity * (size_type)sizeof(T));
} else {
_storage = 0;
}
}
void freeStorage(T *storage, const size_type elements) {
for (size_type i = 0; i < elements; ++i)
storage[i].~T();
free(storage);
}
/**
* Insert a range of elements coming from this or another array.
* Unlike std::vector::insert, this method does not accept
* arbitrary iterators, mainly because our iterator system is
* seriously limited and does not distinguish between input iterators,
* output iterators, forward iterators or random access iterators.
*
* So, we simply restrict to Array iterators. Extending this to arbitrary
* random access iterators would be trivial.
*
* Moreover, this method does not handle all cases of inserting a subrange
* of an array into itself; this is why it is private for now.
*/
iterator insert_aux(iterator pos, const_iterator first, const_iterator last) {
assert(_storage <= pos && pos <= _storage + _size);
assert(first <= last);
const size_type n = last - first;
if (n) {
const size_type idx = pos - _storage;
if (_size + n > _capacity || (_storage <= first && first <= _storage + _size)) {
T *const oldStorage = _storage;
// If there is not enough space, allocate more.
// Likewise, if this is a self-insert, we allocate new
// storage to avoid conflicts.
allocCapacity(roundUpCapacity(_size + n));
// Copy the data from the old storage till the position where
// we insert new data
uninitialized_copy(oldStorage, oldStorage + idx, _storage);
// Copy the data we insert
uninitialized_copy(first, last, _storage + idx);
// Afterwards copy the old data from the position where we
// insert.
uninitialized_copy(oldStorage + idx, oldStorage + _size, _storage + idx + n);
freeStorage(oldStorage, _size);
} else if (idx + n <= _size) {
// Make room for the new elements by shifting back
// existing ones.
// 1. Move a part of the data to the uninitialized area
uninitialized_copy(_storage + _size - n, _storage + _size, _storage + _size);
// 2. Move a part of the data to the initialized area
copy_backward(pos, _storage + _size - n, _storage + _size);
// Insert the new elements.
copy(first, last, pos);
} else {
// Copy the old data from the position till the end to the new
// place.
uninitialized_copy(pos, _storage + _size, _storage + idx + n);
// Copy a part of the new data to the position inside the
// initialized space.
copy(first, first + (_size - idx), pos);
// Copy a part of the new data to the position inside the
// uninitialized space.
uninitialized_copy(first + (_size - idx), last, _storage + _size);
}
// Finally, update the internal state
_size += n;
}
return pos;
}
};
/**
* Double linked list with sorted nodes.
*/
template<class T>
class SortedArray : public Array<T> {
public:
typedef T *iterator;
typedef uint size_type;
SortedArray(int (*comparator)(const void *, const void *)) {
_comparator = comparator;
}
/**
* Inserts element at the sorted position.
*/
void insert(const T &element) {
T *where = (T *)bsearch(element, this->front(), this->_size, sizeof(T), _comparator);
insert(where, element);
}
T &operator[](size_type idx) {
error("Operation not allowed with SortedArray");
}
void insert_at(size_type idx, const T &element) {
error("Operation not allowed with SortedArray");
}
void insert_at(size_type idx, const Array<T> &array) {
error("Operation not allowed with SortedArray");
}
void insert(iterator pos, const T &element) {
error("Operation not allowed with SortedArray");
}
void push_back(const T &element) {
error("Operation not allowed with SortedArray");
}
void push_back(const Array<T> &array) {
error("Operation not allowed with SortedArray");
}
private:
int (*_comparator)(const void *, const void *);
};
} // End of namespace Common
#endif
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