--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/corelib/tools/qcontiguouscache.h Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,437 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QCONTIGUOUSCACHE_H
+#define QCONTIGUOUSCACHE_H
+
+#include <QtCore/qatomic.h>
+#include <limits.h>
+#include <new>
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+#undef QT_QCONTIGUOUSCACHE_DEBUG
+QT_MODULE(Core)
+
+
+struct Q_CORE_EXPORT QContiguousCacheData
+{
+ QBasicAtomicInt ref;
+ int alloc;
+ int count;
+ int start;
+ int offset;
+ uint sharable : 1;
+
+#ifdef QT_QCONTIGUOUSCACHE_DEBUG
+ void dump() const;
+#endif
+};
+
+template <typename T>
+struct QContiguousCacheTypedData
+{
+ QBasicAtomicInt ref;
+ int alloc;
+ int count;
+ int start;
+ int offset;
+ uint sharable : 1;
+ // uint unused : 31;
+
+ // total is 24 bytes (HP-UX aCC: 40 bytes)
+ // the next entry is already aligned to 8 bytes
+ // there will be an 8 byte gap here if T requires 16-byte alignment
+ // (such as long double on 64-bit platforms, __int128, __float128)
+
+ T array[1];
+};
+
+template<typename T>
+class QContiguousCache {
+ typedef QContiguousCacheTypedData<T> Data;
+ union { QContiguousCacheData *p; QContiguousCacheTypedData<T> *d; };
+public:
+ explicit QContiguousCache(int capacity = 0);
+ QContiguousCache(const QContiguousCache<T> &v) : d(v.d) { d->ref.ref(); if (!d->sharable) detach_helper(); }
+
+ inline ~QContiguousCache() { if (!d) return; if (!d->ref.deref()) free(d); }
+
+ inline void detach() { if (d->ref != 1) detach_helper(); }
+ inline bool isDetached() const { return d->ref == 1; }
+ inline void setSharable(bool sharable) { if (!sharable) detach(); d->sharable = sharable; }
+
+ QContiguousCache<T> &operator=(const QContiguousCache<T> &other);
+ bool operator==(const QContiguousCache<T> &other) const;
+ inline bool operator!=(const QContiguousCache<T> &other) const { return !(*this == other); }
+
+ inline int capacity() const {return d->alloc; }
+ inline int count() const { return d->count; }
+ inline int size() const { return d->count; }
+
+ inline bool isEmpty() const { return d->count == 0; }
+ inline bool isFull() const { return d->count == d->alloc; }
+ inline int available() const { return d->alloc - d->count; }
+
+ void clear();
+ void setCapacity(int size);
+
+ const T &at(int pos) const;
+ T &operator[](int i);
+ const T &operator[](int i) const;
+
+ void append(const T &value);
+ void prepend(const T &value);
+ void insert(int pos, const T &value);
+
+ inline bool containsIndex(int pos) const { return pos >= d->offset && pos - d->offset < d->count; }
+ inline int firstIndex() const { return d->offset; }
+ inline int lastIndex() const { return d->offset + d->count - 1; }
+
+ inline const T &first() const { Q_ASSERT(!isEmpty()); return d->array[d->start]; }
+ inline const T &last() const { Q_ASSERT(!isEmpty()); return d->array[(d->start + d->count -1) % d->alloc]; }
+ inline T &first() { Q_ASSERT(!isEmpty()); detach(); return d->array[d->start]; }
+ inline T &last() { Q_ASSERT(!isEmpty()); detach(); return d->array[(d->start + d->count -1) % d->alloc]; }
+
+ void removeFirst();
+ T takeFirst();
+ void removeLast();
+ T takeLast();
+
+ inline bool areIndexesValid() const
+ { return d->offset >= 0 && d->offset < INT_MAX - d->count && (d->offset % d->alloc) == d->start; }
+
+ inline void normalizeIndexes() { d->offset = d->start; }
+
+#ifdef QT_QCONTIGUOUSCACHE_DEBUG
+ void dump() const { p->dump(); }
+#endif
+private:
+ void detach_helper();
+
+ QContiguousCacheData *malloc(int aalloc);
+ void free(Data *x);
+ int sizeOfTypedData() {
+ // this is more or less the same as sizeof(Data), except that it doesn't
+ // count the padding at the end
+ return reinterpret_cast<const char *>(&(reinterpret_cast<const Data *>(this))->array[1]) - reinterpret_cast<const char *>(this);
+ }
+};
+
+template <typename T>
+void QContiguousCache<T>::detach_helper()
+{
+ union { QContiguousCacheData *p; QContiguousCacheTypedData<T> *d; } x;
+
+ x.p = malloc(d->alloc);
+ x.d->ref = 1;
+ x.d->count = d->count;
+ x.d->start = d->start;
+ x.d->offset = d->offset;
+ x.d->alloc = d->alloc;
+ x.d->sharable = true;
+
+ T *dest = x.d->array + x.d->start;
+ T *src = d->array + d->start;
+ int oldcount = x.d->count;
+ while (oldcount--) {
+ if (QTypeInfo<T>::isComplex) {
+ new (dest) T(*src);
+ } else {
+ *dest = *src;
+ }
+ dest++;
+ if (dest == x.d->array + x.d->alloc)
+ dest = x.d->array;
+ src++;
+ if (src == d->array + d->alloc)
+ src = d->array;
+ }
+
+ if (!d->ref.deref())
+ free(d);
+ d = x.d;
+}
+
+template <typename T>
+void QContiguousCache<T>::setCapacity(int asize)
+{
+ if (asize == d->alloc)
+ return;
+ detach();
+ union { QContiguousCacheData *p; QContiguousCacheTypedData<T> *d; } x;
+ x.p = malloc(asize);
+ x.d->alloc = asize;
+ x.d->count = qMin(d->count, asize);
+ x.d->offset = d->offset + d->count - x.d->count;
+ x.d->start = x.d->offset % x.d->alloc;
+ T *dest = x.d->array + (x.d->start + x.d->count-1) % x.d->alloc;
+ T *src = d->array + (d->start + d->count-1) % d->alloc;
+ int oldcount = x.d->count;
+ while (oldcount--) {
+ if (QTypeInfo<T>::isComplex) {
+ new (dest) T(*src);
+ } else {
+ *dest = *src;
+ }
+ if (dest == x.d->array)
+ dest = x.d->array + x.d->alloc;
+ dest--;
+ if (src == d->array)
+ src = d->array + d->alloc;
+ src--;
+ }
+ /* free old */
+ free(d);
+ d = x.d;
+}
+
+template <typename T>
+void QContiguousCache<T>::clear()
+{
+ if (d->ref == 1) {
+ if (QTypeInfo<T>::isComplex) {
+ int oldcount = d->count;
+ T * i = d->array + d->start;
+ T * e = d->array + d->alloc;
+ while (oldcount--) {
+ i->~T();
+ i++;
+ if (i == e)
+ i = d->array;
+ }
+ }
+ d->count = d->start = d->offset = 0;
+ } else {
+ union { QContiguousCacheData *p; QContiguousCacheTypedData<T> *d; } x;
+ x.p = malloc(d->alloc);
+ x.d->ref = 1;
+ x.d->alloc = d->alloc;
+ x.d->count = x.d->start = x.d->offset = 0;
+ x.d->sharable = true;
+ if (!d->ref.deref()) free(d);
+ d = x.d;
+ }
+}
+
+template <typename T>
+inline QContiguousCacheData *QContiguousCache<T>::malloc(int aalloc)
+{
+ return static_cast<QContiguousCacheData *>(qMalloc(sizeOfTypedData() + (aalloc - 1) * sizeof(T)));
+}
+
+template <typename T>
+QContiguousCache<T>::QContiguousCache(int cap)
+{
+ p = malloc(cap);
+ d->ref = 1;
+ d->alloc = cap;
+ d->count = d->start = d->offset = 0;
+ d->sharable = true;
+}
+
+template <typename T>
+QContiguousCache<T> &QContiguousCache<T>::operator=(const QContiguousCache<T> &other)
+{
+ other.d->ref.ref();
+ if (!d->ref.deref())
+ free(d);
+ d = other.d;
+ if (!d->sharable)
+ detach_helper();
+ return *this;
+}
+
+template <typename T>
+bool QContiguousCache<T>::operator==(const QContiguousCache<T> &other) const
+{
+ if (other.d == d)
+ return true;
+ if (other.d->start != d->start
+ || other.d->count != d->count
+ || other.d->offset != d->offset
+ || other.d->alloc != d->alloc)
+ return false;
+ for (int i = firstIndex(); i <= lastIndex(); ++i)
+ if (!(at(i) == other.at(i)))
+ return false;
+ return true;
+}
+
+template <typename T>
+void QContiguousCache<T>::free(Data *x)
+{
+ if (QTypeInfo<T>::isComplex) {
+ int oldcount = d->count;
+ T * i = d->array + d->start;
+ T * e = d->array + d->alloc;
+ while (oldcount--) {
+ i->~T();
+ i++;
+ if (i == e)
+ i = d->array;
+ }
+ }
+ qFree(x);
+}
+template <typename T>
+void QContiguousCache<T>::append(const T &value)
+{
+ detach();
+ if (QTypeInfo<T>::isComplex) {
+ if (d->count == d->alloc)
+ (d->array + (d->start+d->count) % d->alloc)->~T();
+ new (d->array + (d->start+d->count) % d->alloc) T(value);
+ } else {
+ d->array[(d->start+d->count) % d->alloc] = value;
+ }
+
+ if (d->count == d->alloc) {
+ d->start++;
+ d->start %= d->alloc;
+ d->offset++;
+ } else {
+ d->count++;
+ }
+}
+
+template<typename T>
+void QContiguousCache<T>::prepend(const T &value)
+{
+ detach();
+ if (d->start)
+ d->start--;
+ else
+ d->start = d->alloc-1;
+ d->offset--;
+
+ if (d->count != d->alloc)
+ d->count++;
+ else
+ if (d->count == d->alloc)
+ (d->array + d->start)->~T();
+
+ if (QTypeInfo<T>::isComplex)
+ new (d->array + d->start) T(value);
+ else
+ d->array[d->start] = value;
+}
+
+template<typename T>
+void QContiguousCache<T>::insert(int pos, const T &value)
+{
+ Q_ASSERT_X(pos >= 0 && pos < INT_MAX, "QContiguousCache<T>::insert", "index out of range");
+ detach();
+ if (containsIndex(pos)) {
+ if(QTypeInfo<T>::isComplex)
+ new (d->array + pos % d->alloc) T(value);
+ else
+ d->array[pos % d->alloc] = value;
+ } else if (pos == d->offset-1)
+ prepend(value);
+ else if (pos == d->offset+d->count)
+ append(value);
+ else {
+ // we don't leave gaps.
+ clear();
+ d->offset = pos;
+ d->start = pos % d->alloc;
+ d->count = 1;
+ if (QTypeInfo<T>::isComplex)
+ new (d->array + d->start) T(value);
+ else
+ d->array[d->start] = value;
+ }
+}
+
+template <typename T>
+inline const T &QContiguousCache<T>::at(int pos) const
+{ Q_ASSERT_X(pos >= d->offset && pos - d->offset < d->count, "QContiguousCache<T>::at", "index out of range"); return d->array[pos % d->alloc]; }
+template <typename T>
+inline const T &QContiguousCache<T>::operator[](int pos) const
+{ Q_ASSERT_X(pos >= d->offset && pos - d->offset < d->count, "QContiguousCache<T>::at", "index out of range"); return d->array[pos % d->alloc]; }
+
+template <typename T>
+inline T &QContiguousCache<T>::operator[](int pos)
+{
+ detach();
+ if (!containsIndex(pos))
+ insert(pos, T());
+ return d->array[pos % d->alloc];
+}
+
+template <typename T>
+inline void QContiguousCache<T>::removeFirst()
+{
+ Q_ASSERT(d->count > 0);
+ detach();
+ d->count--;
+ if (QTypeInfo<T>::isComplex)
+ (d->array + d->start)->~T();
+ d->start = (d->start + 1) % d->alloc;
+ d->offset++;
+}
+
+template <typename T>
+inline void QContiguousCache<T>::removeLast()
+{
+ Q_ASSERT(d->count > 0);
+ detach();
+ d->count--;
+ if (QTypeInfo<T>::isComplex)
+ (d->array + (d->start + d->count) % d->alloc)->~T();
+}
+
+template <typename T>
+inline T QContiguousCache<T>::takeFirst()
+{ T t = first(); removeFirst(); return t; }
+
+template <typename T>
+inline T QContiguousCache<T>::takeLast()
+{ T t = last(); removeLast(); return t; }
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif