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Diffstat (limited to 'common/span.h')
| -rw-r--r-- | common/span.h | 1038 |
1 files changed, 1038 insertions, 0 deletions
diff --git a/common/span.h b/common/span.h new file mode 100644 index 0000000000..a6c393fd53 --- /dev/null +++ b/common/span.h @@ -0,0 +1,1038 @@ +/* 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_SPAN_H +#define COMMON_SPAN_H + +#include "common/file.h" +#include "common/memstream.h" +#include "common/safe-bool.h" +#include "common/scummsys.h" +#include "common/type-traits.h" + +namespace Common { + +enum { + kSpanMaxSize = 0xFFFFFFFF, + kSpanKeepOffset = 0xFFFFFFFF +}; + +#pragma mark - +#pragma mark SpanValidationMode + +enum SpanValidationMode { + kValidateRead, + kValidateWrite, + kValidateSeek +}; + +namespace SpanInternal { +#pragma mark - +#pragma mark SpanIterator + /** + * Bounds-checked iteration over a span of memory. + */ + template <typename Span, bool IsConst> + class SpanIterator { + typedef typename Span::value_type span_value_type; + typedef typename Conditional<IsConst, const Span, Span>::type span_type; + + public: + typedef typename Span::difference_type difference_type; + typedef typename RemoveConst<span_value_type>::type value_type; + typedef typename Conditional<IsConst, const span_value_type, span_value_type>::type *pointer; + typedef typename Conditional<IsConst, const span_value_type, span_value_type>::type &reference; + + inline SpanIterator() : _span(nullptr), _index(0) {} + + inline SpanIterator(span_type *const span, const difference_type index) : + _span(span), + _index(index) { + if (span != nullptr) { + span->validate(index, 0, kValidateSeek); + } + } + + inline SpanIterator(const SpanIterator &other) : + _span(other._span), + _index(other._index) {} + + inline SpanIterator &operator=(const SpanIterator &other) { + _span = other._span; + _index = other._index; + return *this; + } + +#pragma mark - +#pragma mark SpanIterator - Dereferencing operations + + public: + inline reference operator*() const { + // validation is in Span::operator[] + return (*_span)[_index]; + } + + inline pointer operator->() const { + return &operator*(); + } + + inline reference operator[](const difference_type index) const { + // validation is in SpanIterator::operator+= + return *(*this + index); + } + +#pragma mark - +#pragma mark SpanIterator - Arithmetic operations + + public: + inline SpanIterator &operator+=(const difference_type delta) { + assert(_span != nullptr); + _span->validate(_index, delta, kValidateSeek); + _index += delta; + return *this; + } + + inline SpanIterator &operator-=(const difference_type delta) { + return operator+=(-delta); + } + + inline SpanIterator &operator++() { + return operator+=(1); + } + + inline SpanIterator operator++(int) { + SpanIterator old(*this); + operator+=(1); + return old; + } + + inline SpanIterator &operator--() { + return operator+=(-1); + } + + inline SpanIterator operator--(int) { + SpanIterator old(*this); + operator+=(-1); + return old; + } + + inline SpanIterator operator+(const difference_type delta) const { + SpanIterator it(*this); + return it += delta; + } + + inline SpanIterator operator-(const difference_type delta) const { + return operator+(-delta); + } + + inline difference_type operator-(const SpanIterator &other) const { + assert(_span == other._span); + return _index - other._index; + } + +#pragma mark - +#pragma mark SpanIterator - Comparison operations + + public: + inline bool operator==(const SpanIterator& other) const { + return _span == other._span && _index == other._index; + } + + inline bool operator!=(const SpanIterator& other) const { + return !operator==(other); + } + + inline bool operator<(const SpanIterator& other) const { + assert(_span == other._span); + return _index < other._index; + } + + inline bool operator<=(const SpanIterator& other) const { + return !other.operator<(*this); + } + + inline bool operator>(const SpanIterator& other) const { + return other.operator<(*this); + } + + inline bool operator>=(const SpanIterator& other) const { + return !operator<(other); + } + +#pragma mark - +#pragma mark SpanIterator - Data access convenience functions + + public: + inline int8 getInt8() const { + return _span->getInt8At(_index); + } + + inline uint8 getUint8() const { + return _span->getUint8At(_index); + } + + inline int16 getInt16BE() const { + return _span->getInt16BEAt(_index); + } + + inline int16 getInt16LE() const { + return _span->getInt16LEAt(_index); + } + + inline uint16 getUint16BE() const { + return _span->getUint16BEAt(_index); + } + + inline uint16 getUint16LE() const { + return _span->getUint16LEAt(_index); + } + + inline uint32 getUint24LE() const { + return _span->getUint24LEAt(_index); + } + + inline uint32 getUint32() const { + return _span->getUint32At(_index); + } + + inline int32 getInt32BE() const { + return _span->getInt32BEAt(_index); + } + + inline int32 getInt32LE() const { + return _span->getInt32LEAt(_index); + } + + inline uint32 getUint32BE() const { + return _span->getUint32BEAt(_index); + } + + inline uint32 getUint32LE() const { + return _span->getUint32LEAt(_index); + } + + protected: + span_type *_span; + difference_type _index; + }; +} // End of namespace SpanInternal + +#pragma mark - +#pragma mark SpanBase + +template <typename ValueType, template <typename> class Derived> +class SpanBase : public SafeBool<Derived<ValueType> > { + typedef Derived<ValueType> derived_type; + typedef typename AddConst<derived_type>::type const_derived_type; + typedef typename RemoveConst<derived_type>::type mutable_derived_type; + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) + template <typename T, bool U> friend class SpanInternal::SpanIterator; + template <typename T, template <typename> class U> friend class SpanBase; + template <typename T, typename U> friend struct SafeBool; +#endif +#ifdef CXXTEST_RUNNING + friend class ::SpanTestSuite; +#endif + +public: + typedef ValueType value_type; + typedef ptrdiff_t difference_type; + typedef size_t index_type; + typedef size_t size_type; + typedef SpanInternal::SpanIterator<derived_type, true> const_iterator; + typedef SpanInternal::SpanIterator<derived_type, false> iterator; + typedef value_type *pointer; + typedef const value_type *const_pointer; + typedef value_type &reference; + typedef const value_type &const_reference; + + inline size_type byteSize() const { return impl().size() * sizeof(value_type); } + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + SpanBase() {} + SpanBase(const SpanBase &) {} + void operator=(const SpanBase &) {} + ~SpanBase() {} + + inline const_derived_type &impl() const { return static_cast<const_derived_type &>(*this); } + inline mutable_derived_type &impl() { return static_cast<mutable_derived_type &>(*this); } + +#pragma mark - +#pragma mark SpanBase - Interface + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + inline void clear(); + + inline size_type size() const; + + inline const_iterator cbegin() const; + inline const_iterator cend() const; + inline const_iterator begin() const; + inline const_iterator end() const; + inline iterator begin(); + inline iterator end(); + + inline const value_type *data() const; + inline value_type *data(); + +#pragma mark - +#pragma mark SpanBase - Data access functions + +public: + inline const_reference operator[](const index_type index) const { + impl().validate(index, sizeof(value_type)); + return impl().data()[index]; + } + + inline reference operator[](const index_type index) { + impl().validate(index, sizeof(value_type)); + return impl().data()[index]; + } + + inline int8 getInt8At(const index_type index) const { + return (int8)impl()[index]; + } + + inline uint8 getUint8At(const index_type index) const { + return (uint8)impl()[index]; + } + + inline int16 getInt16BEAt(const index_type index) const { + return (int16)impl().getUint16BEAt(index); + } + + inline int16 getInt16LEAt(const index_type index) const { + return (int16)impl().getUint16LEAt(index); + } + + inline uint16 getUint16BEAt(const index_type index) const { + impl().validate(index, sizeof(uint16)); + return READ_BE_UINT16(impl().data() + index); + } + + inline uint16 getUint16LEAt(const index_type index) const { + impl().validate(index, sizeof(uint16)); + return READ_LE_UINT16(impl().data() + index); + } + + inline uint32 getUint24LEAt(const index_type index) const { + impl().validate(index, 3); + return READ_LE_UINT24(impl().data() + index); + } + + inline uint32 getUint32At(const index_type index) const { + impl().validate(index, sizeof(uint32)); + return READ_UINT32(impl().data() + index); + } + + inline int32 getInt32BEAt(const index_type index) const { + return (int32)impl().getUint32BEAt(index); + } + + inline int32 getInt32LEAt(const index_type index) const { + return (int32)impl().getUint32LEAt(index); + } + + inline uint32 getUint32BEAt(const index_type index) const { + impl().validate(index, sizeof(uint32)); + return READ_BE_UINT32(impl().data() + index); + } + + inline uint32 getUint32LEAt(const index_type index) const { + impl().validate(index, sizeof(uint32)); + return READ_LE_UINT32(impl().data() + index); + } + + inline String getStringAt(const index_type index, size_type numEntries = kSpanMaxSize) const { + if (numEntries == kSpanMaxSize) { + const char *string = (const char *)impl().data(); + numEntries = strnlen(string, (impl().size() - index) * sizeof(value_type)) / sizeof(value_type); + } + impl().validate(index, numEntries * sizeof(value_type)); + return String((const char *)(impl().data() + index), numEntries); + } + + /** + * Returns a raw pointer to memory after validating the given index and + * size. Use this only in performance-critical code, like processing pixel + * data in a loop, where validating each read independently would introduce + * unnecessary overhead. + */ + inline const_pointer getUnsafeDataAt(const index_type index, size_type numEntries = kSpanMaxSize) const { + if (numEntries == kSpanMaxSize) { + numEntries = impl().size() - index; + } + + impl().validate(index, numEntries); + return impl().data() + index; + } + + inline pointer getUnsafeDataAt(const index_type index, size_type numEntries = kSpanMaxSize) { + if (numEntries == kSpanMaxSize) { + numEntries = impl().size() - index; + } + + impl().validate(index, numEntries); + return impl().data() + index; + } + + inline MemoryReadStream toStream(const index_type index = 0, size_type numEntries = kSpanMaxSize) const { + if (numEntries == kSpanMaxSize) { + numEntries = impl().size(); + } + + impl().validate(index, numEntries * sizeof(value_type)); + return MemoryReadStream(impl().data() + index, numEntries, DisposeAfterUse::NO); + } + +#pragma mark - +#pragma mark SpanBase - Operators + +public: + template <typename Other> + inline bool operator==(const Other &other) const { + return impl().data() == other.impl().data() && impl().size() == other.impl().size(); + } + + template <typename Other> + inline bool operator!=(const Other &other) const { + return !operator==(other); + } + + template <typename Other> + inline difference_type operator-(const Other &other) const { + return impl().data() - other.impl().data(); + } + + template <typename Other> + inline bool operator<(const Other &other) const { + return impl().data() < other.impl().data(); + } + + template <typename Other> + inline bool operator<=(const Other &other) const { + return !other.operator<(*this); + } + + template <typename Other> + inline bool operator>(const Other &other) const { + return other.operator<(*this); + } + + template <typename Other> + inline bool operator>=(const Other &other) const { + return !operator<(other); + } + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + inline bool operator_bool() const { return impl().data() != nullptr; } + +#pragma mark - +#pragma mark SpanBase - Copying + +public: + /** + * Copies data from this span to a raw pointer. To only copy a portion of + * the span, call subspan first. + */ + inline void unsafeCopyDataTo(void *target) const { + memcpy(target, impl().data(), impl().byteSize()); + } + + /** + * Copies the data from this span to the given target span. To only copy a + * portion of the span, call subspan first. + */ + template <typename Other> + inline void copyDataTo(Other &target) const { + assert((impl().byteSize() % sizeof(typename Other::value_type)) == 0); + target.impl().validate(0, impl().byteSize(), kValidateWrite); + memcpy(target.impl().data(), impl().data(), impl().byteSize()); + } + +#pragma mark - +#pragma mark SpanBase - Validation + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + inline bool checkInvalidBounds(const index_type index, const difference_type deltaInBytes) const { + // There is a potential that large bogus values may cause arithmetic + // overflow, so the individual operands are checked separately first. + // Values that are not allowed to be negative are treated as unsigned to + // reduce the number of necessary comparisons + const size_t maxByteOffset = index * (signed)sizeof(value_type) + deltaInBytes; + return index > impl().size() || deltaInBytes > (difference_type)impl().byteSize() || maxByteOffset > impl().byteSize(); + } + + inline void validate(const index_type index, const difference_type deltaInBytes, const SpanValidationMode mode = kValidateRead) const { + if (impl().checkInvalidBounds(index, deltaInBytes)) { + error("%s", impl().getValidationMessage(index, deltaInBytes, mode).c_str()); + } + } +}; + +#pragma mark - +#pragma mark SpanImpl + +template <typename ValueType, template <typename> class Derived> +class SpanImpl : public SpanBase<ValueType, Derived> { + typedef SpanBase<ValueType, Derived> super_type; + typedef typename AddConst<Derived<ValueType> >::type const_derived_type; + typedef typename RemoveConst<Derived<ValueType> >::type mutable_derived_type; + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) + template <typename T, template <typename> class U> friend class SpanImpl; +#endif +#ifdef CXXTEST_RUNNING + friend class ::SpanTestSuite; +#endif + +public: + typedef typename super_type::value_type value_type; + typedef typename super_type::difference_type difference_type; + typedef typename super_type::index_type index_type; + typedef typename super_type::size_type size_type; + typedef typename super_type::const_iterator const_iterator; + typedef typename super_type::iterator iterator; + typedef typename super_type::pointer pointer; + typedef typename super_type::const_pointer const_pointer; + typedef typename super_type::reference reference; + typedef typename super_type::const_reference const_reference; + + inline SpanImpl() : super_type(), _data(nullptr), _size(0) {} + + inline SpanImpl(const pointer data_, const size_type size_) : + super_type(), + _data(data_), + _size(size_) {} + + template <typename Other> + inline SpanImpl(const Other &other) : + super_type(), + _data(other.data()), + _size(other.size()) {} + + template <typename Other> + inline mutable_derived_type &operator=(const Other &other) { + // TODO: Is there a better way to do this which avoids casting away + // const in the case that value_type is explicitly defined const? + _data = const_cast<typename Other::pointer>(other.data()); + _size = other.size(); + return this->impl(); + } + + inline ~SpanImpl() {} + + inline void clear() { + _data = nullptr; + _size = 0; + } + + inline size_type size() const { return _size; } + inline const_pointer data() const { return _data; } + inline pointer data() { return _data; } + + inline const_iterator cbegin() const { return const_iterator(&this->impl(), 0); } + inline const_iterator cend() const { return const_iterator(&this->impl(), size()); } + inline const_iterator begin() const { return const_iterator(&this->impl(), 0); } + inline const_iterator end() const { return const_iterator(&this->impl(), size()); } + inline iterator begin() { return iterator(&this->impl(), 0); } + inline iterator end() { return iterator(&this->impl(), size()); } + + const String name() const { return String::format("%p", static_cast<const void *>(data())); } + + String getValidationMessage(const index_type index, const difference_type deltaInBytes, const SpanValidationMode mode) const { + const char *modeName; + switch (mode) { + case kValidateRead: + modeName = "reading"; + break; + case kValidateWrite: + modeName = "writing"; + break; + case kValidateSeek: + modeName = "seeking"; + break; + } + + return String::format("Access violation %s %s: %ld + %ld > %ld", + modeName, + this->impl().name().c_str(), + index, + deltaInBytes / sizeof(value_type), + size()); + } + +#pragma mark - +#pragma mark SpanImpl - Subspan + +public: + template <typename NewValueType> + inline const Derived<NewValueType> subspan(const index_type index, size_type numEntries = kSpanMaxSize) const { + Derived<NewValueType> span; + populateSubspan(span, index, numEntries); + return span; + } + + template <typename NewValueType> + inline Derived<NewValueType> subspan(const index_type index, size_type numEntries = kSpanMaxSize) { + Derived<NewValueType> span; + populateSubspan(span, index, numEntries); + return span; + } + + inline const_derived_type subspan(const index_type index, const size_type numEntries = kSpanMaxSize) const { + return subspan<value_type>(index, numEntries); + } + + inline mutable_derived_type subspan(const index_type index, const size_type numEntries = kSpanMaxSize) { + return subspan<value_type>(index, numEntries); + } + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + template <typename NewValueType> + void populateSubspan(Derived<NewValueType> &span, const index_type index, size_type numEntries) const { + if (numEntries == kSpanMaxSize) { + numEntries = CLIP<size_type>(size() - index, 0, size()); + } + + assert(numEntries * sizeof(value_type) % sizeof(NewValueType) == 0); + this->validate(index, numEntries * sizeof(value_type), kValidateSeek); + + span._data = (NewValueType *)const_cast<mutable_value_type *>(_data + index); + span._size = numEntries * sizeof(value_type) / sizeof(NewValueType); + } + +#pragma mark - +#pragma mark SpanImpl - Allocation + +private: + typedef typename RemoveConst<value_type>::type mutable_value_type; + typedef Derived<mutable_value_type> mutable_value_derived_type; + +public: + mutable_value_derived_type &allocate(const size_type numEntries) { + assert(_data == nullptr); + assert(numEntries != kSpanMaxSize); + _data = new mutable_value_type[numEntries]; + _size = numEntries; + return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl()); + } + + template <typename Other> + mutable_value_derived_type &allocateFromSpan(const Other &other) { + assert(_data == nullptr); + assert(sizeof(value_type) == sizeof(typename Other::value_type)); + _data = new mutable_value_type[other.size()]; + _size = other.size(); + copy(other.begin(), other.end(), const_cast<mutable_value_type *>(_data)); + return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl()); + } + + mutable_value_derived_type &allocateFromStream(SeekableReadStream &stream, size_type numEntries = kSpanMaxSize) { + if (numEntries == kSpanMaxSize) { + numEntries = (stream.size() - stream.pos()) / sizeof(value_type); + } + + assert(stream.pos() + numEntries * sizeof(value_type) <= (uint)stream.size()); + allocate(numEntries); + stream.read((void *)const_cast<mutable_value_type *>(_data), numEntries * sizeof(value_type)); + return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl()); + } + + value_type *_data; + size_type _size; +}; + +#pragma mark - +#pragma mark Span + +template <typename ValueType> +class Span : public SpanImpl<ValueType, Span> { + typedef SpanImpl<ValueType, ::Common::Span> super_type; + typedef typename AddConst<Span<ValueType> >::type const_derived_type; + typedef typename RemoveConst<Span<ValueType> >::type mutable_derived_type; +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) + template <typename T> friend class Span; +#endif + +public: + typedef typename super_type::value_type value_type; + typedef typename super_type::difference_type difference_type; + typedef typename super_type::index_type index_type; + typedef typename super_type::size_type size_type; + typedef typename super_type::const_iterator const_iterator; + typedef typename super_type::iterator iterator; + typedef typename super_type::pointer pointer; + typedef typename super_type::const_pointer const_pointer; + typedef typename super_type::reference reference; + typedef typename super_type::const_reference const_reference; + + inline Span() : super_type() {} + + inline Span(const pointer data_, const size_type size_) : super_type(data_, size_) {} + + template <typename Other> + inline Span(const Other &other) : super_type(other) {} + + template <typename Other> + inline mutable_derived_type &operator=(const Other &other) { + super_type::operator=(other); + return this->impl(); + } + + inline ~Span() {} +}; + +#pragma mark - +#pragma mark NamedSpanImpl + +template <typename ValueType, template <typename> class Derived> +class NamedSpanImpl : public SpanImpl<ValueType, Derived> { + typedef SpanImpl<ValueType, Derived> super_type; + typedef typename AddConst<Derived<ValueType> >::type const_derived_type; + typedef typename RemoveConst<Derived<ValueType> >::type mutable_derived_type; + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) + template <typename T, template <typename> class U> friend class NamedSpanImpl; +#endif +#ifdef CXXTEST_RUNNING + friend class ::SpanTestSuite; +#endif + +public: + typedef typename super_type::value_type value_type; + typedef typename super_type::difference_type difference_type; + typedef typename super_type::index_type index_type; + typedef typename super_type::size_type size_type; + typedef typename super_type::const_iterator const_iterator; + typedef typename super_type::iterator iterator; + typedef typename super_type::pointer pointer; + typedef typename super_type::const_pointer const_pointer; + typedef typename super_type::reference reference; + typedef typename super_type::const_reference const_reference; + + inline NamedSpanImpl() : super_type(), _name(), _sourceByteOffset(0) {} + + inline NamedSpanImpl(const pointer data_, + const size_type size_, + const String &name = String(), + const size_type sourceByteOffset = 0) : + super_type(data_, size_), + _name(name), + _sourceByteOffset(sourceByteOffset) {} + + template <typename OtherValueType> + inline NamedSpanImpl(const NamedSpanImpl<OtherValueType, Derived> &other) : + super_type(other), + _name(other.name()), + _sourceByteOffset(other.sourceByteOffset()) {} + + template <typename OtherValueType> + inline NamedSpanImpl(const SpanImpl<OtherValueType, Derived> &other) : + super_type(other), + _name(String::format("%p", const_cast<const void *>(other.data()))), + _sourceByteOffset(0) {} + + template <typename OtherValueType> + inline mutable_derived_type &operator=(const NamedSpanImpl<OtherValueType, Derived> &other) { + super_type::operator=(other); + _name = other.name(); + _sourceByteOffset = other.sourceByteOffset(); + return this->impl(); + } + + template <typename OtherValueType> + inline mutable_derived_type &operator=(const SpanImpl<OtherValueType, Derived> &other) { + super_type::operator=(other); + _name = String::format("%p", const_cast<const void *>(other.data())); + _sourceByteOffset = 0; + return this->impl(); + } + + inline ~NamedSpanImpl() {} + + inline void clear() { + super_type::clear(); + _name.clear(); + _sourceByteOffset = 0; + } + + const String &name() const { return _name; } + String &name() { return _name; } + + const size_type &sourceByteOffset() const { return _sourceByteOffset; } + size_type &sourceByteOffset() { return _sourceByteOffset; } + +private: + String _name; + size_type _sourceByteOffset; + +#pragma mark - +#pragma mark NamedSpanImpl - Subspan + +public: + template <typename NewValueType> + inline const Derived<NewValueType> subspan(const index_type index, const size_type numEntries = kSpanMaxSize, const String &name = String(), const size_type sourceByteOffset = kSpanKeepOffset) const { + Derived<NewValueType> span; + populateSubspan(span, index, numEntries, name, sourceByteOffset); + return span; + } + + template <typename NewValueType> + inline Derived<NewValueType> subspan(const index_type index, const size_type numEntries = kSpanMaxSize, const String &name = String(), const size_type sourceByteOffset = kSpanKeepOffset) { + Derived<NewValueType> span; + populateSubspan(span, index, numEntries, name, sourceByteOffset); + return span; + } + + inline const_derived_type subspan(const index_type index, const size_type numEntries = kSpanMaxSize, const String &name = String(), const size_type sourceByteOffset = kSpanKeepOffset) const { + return subspan<value_type>(index, numEntries, name, sourceByteOffset); + } + + inline mutable_derived_type subspan(const index_type index, const size_type numEntries = kSpanMaxSize, const String &name = String(), const size_type sourceByteOffset = kSpanKeepOffset) { + return subspan<value_type>(index, numEntries, name, sourceByteOffset); + } + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + template <typename NewValueType> + void populateSubspan(Derived<NewValueType> &span, const index_type index, size_type numEntries, const String &name, const size_type sourceByteOffset = kSpanKeepOffset) const { + super_type::template populateSubspan<NewValueType>(span, index, numEntries); + + if (name.empty()) { + span._name = _name; + } else { + span._name = name; + } + + if (sourceByteOffset == kSpanKeepOffset) { + span._sourceByteOffset = _sourceByteOffset + index * sizeof(value_type); + } else { + span._sourceByteOffset = sourceByteOffset; + } + } + +#pragma mark - +#pragma mark NamedSpanImpl - Validation + +public: + String getValidationMessage(const index_type index, const difference_type deltaInBytes, const SpanValidationMode mode) const { + const index_type indexInBytes = index * sizeof(value_type); + const size_type maxSizeInBytes = this->impl().byteSize(); + + return super_type::getValidationMessage(index, deltaInBytes, mode) + + String::format(" (abs: %ld + %ld > %ld)", + this->impl().sourceByteOffset() + indexInBytes, + deltaInBytes, + this->impl().sourceByteOffset() + maxSizeInBytes); + } + +#pragma mark - +#pragma mark NamedSpanImpl - Allocation + +private: + typedef typename RemoveConst<value_type>::type mutable_value_type; + typedef Derived<mutable_value_type> mutable_value_derived_type; + +public: + mutable_value_derived_type &allocate(const size_type numEntries, const String &name = String()) { + super_type::allocate(numEntries); + _name = name; + _sourceByteOffset = 0; + return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl()); + } + + template <typename OtherValueType> + mutable_value_derived_type &allocateFromSpan(const NamedSpanImpl<OtherValueType, Derived> &other) { + super_type::allocateFromSpan(other); + _name = other.name(); + _sourceByteOffset = other.sourceByteOffset(); + return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl()); + } + + using super_type::allocateFromSpan; + + mutable_value_derived_type &allocateFromStream(SeekableReadStream &stream, size_type numEntries = kSpanMaxSize, const String &name = String()) { + super_type::allocateFromStream(stream, numEntries); + _name = name; + _sourceByteOffset = 0; + return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl()); + } + + mutable_value_derived_type &allocateFromStream(File &file, size_type numEntries = kSpanMaxSize) { + return allocateFromStream(file, numEntries, file.getName()); + } +}; + +#pragma mark - +#pragma mark NamedSpan + +template <typename ValueType> +class NamedSpan : public NamedSpanImpl<ValueType, NamedSpan> { + typedef NamedSpanImpl<ValueType, ::Common::NamedSpan> super_type; + typedef typename AddConst<NamedSpan<ValueType> >::type const_derived_type; + typedef typename RemoveConst<NamedSpan<ValueType> >::type mutable_derived_type; + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) + template <typename T> friend class NamedSpan; +#endif + +public: + typedef typename super_type::value_type value_type; + typedef typename super_type::difference_type difference_type; + typedef typename super_type::index_type index_type; + typedef typename super_type::size_type size_type; + typedef typename super_type::const_iterator const_iterator; + typedef typename super_type::iterator iterator; + typedef typename super_type::pointer pointer; + typedef typename super_type::const_pointer const_pointer; + typedef typename super_type::reference reference; + typedef typename super_type::const_reference const_reference; + + inline NamedSpan() : super_type() {} + + inline NamedSpan(const pointer data_, + const size_type size_, + const String &name = String(), + const size_type sourceByteOffset = 0) : + super_type(data_, size_, name, sourceByteOffset) {} + + template <typename Other> + inline NamedSpan(const Other &other) : super_type(other) {} + + template <typename Other> + inline mutable_derived_type &operator=(const Other &other) { + super_type::operator=(other); + return this->impl(); + } + + inline ~NamedSpan() {} +}; + +#pragma mark - +#pragma mark SpanOwner + +/** + * Similar to ScopedPtr, but allows holding and disposing pointers inside Spans + * without requiring an additional pointer to data, and with copyability. + */ +template <typename OwnedSpan> +class SpanOwner : public SafeBool<SpanOwner<OwnedSpan> > { + typedef typename OwnedSpan::value_type value_type; + typedef typename OwnedSpan::size_type size_type; + typedef typename OwnedSpan::index_type index_type; + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) + template <typename T, typename U> friend struct SafeBool; +#endif + +public: + inline SpanOwner() : _span() {} + + inline SpanOwner(const OwnedSpan &span) : _span(span) {} + + /** + * Creates a new owned copy of the memory from the other SpanOwner. + */ + inline SpanOwner(const SpanOwner &other) { + // Allocating memory when copy-constructing from an unallocated owner + // will break the new owner by making it appear allocated even though + // it doesn't (and shouldn't) contain data + if (!other) { + SpanOwner(); + return; + } + + _span.allocateFromSpan(other._span); + } + + /** + * Transfers ownership of the Span from the other owner to this owner. + * If this owner already holds another Span, the old Span will be destroyed. + */ + inline SpanOwner &operator=(SpanOwner &other) { + if (_span.data()) { + delete[] const_cast<typename RemoveConst<value_type>::type *>(_span.data()); + } + _span = other._span; + other.release(); + return *this; + } + + inline ~SpanOwner() { + delete[] const_cast<typename RemoveConst<value_type>::type *>(_span.data()); + } + + /** + * Releases the memory owned by this SpanOwner to the caller. + */ + inline value_type *release() { + value_type *data = _span.data(); + _span.clear(); + return data; + } + + /** + * Destroys the memory owned by this owner. + */ + inline void clear() { + delete[] const_cast<typename RemoveConst<value_type>::type *>(_span.data()); + _span.clear(); + } + +#if !defined(__GNUC__) || GCC_ATLEAST(3, 0) +protected: +#endif + inline bool operator_bool() const { return _span; } + +private: + OwnedSpan _span; + +#pragma mark - +#pragma mark SpanOwner - Data access + +public: + inline const OwnedSpan &operator*() const { return _span; } + inline OwnedSpan &operator*() { return _span; } + + inline const OwnedSpan *operator->() const { return &_span; } + inline OwnedSpan *operator->() { return &_span; } + + inline const value_type &operator[](const index_type index) const { return _span[index]; } + inline value_type &operator[](const index_type index) { return _span[index]; } +}; + +} // End of namespace Common + +#endif |