scummvm/common/span.h
2021-12-26 18:48:43 +01:00

1026 lines
31 KiB
C++

/* 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#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 {
#define COMMON_SPAN_TYPEDEFS \
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;
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 int32 difference_type;
typedef uint32 index_type;
typedef uint32 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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#endif
inline SpanBase() {}
inline SpanBase(const SpanBase &) {}
inline SpanBase &operator=(const SpanBase &) { return this->impl(); }
inline ~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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#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 pointer data() const;
#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 {
STATIC_ASSERT(sizeof(value_type) == sizeof(uint8), int8_can_only_be_read_from_byte_or_char_spans);
return (int8)getUint8At(index);
}
inline uint8 getUint8At(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) == sizeof(uint8), uint8_can_only_be_read_from_byte_or_char_spans);
impl().validate(index, sizeof(uint8));
return (uint8)impl().data()[index];
}
inline int16 getInt16BEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint16), int16_can_only_be_read_from_int16_or_smaller_spans);
return (int16)impl().getUint16BEAt(index);
}
inline int16 getInt16LEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint16), int16_can_only_be_read_from_int16_or_smaller_spans);
return (int16)impl().getUint16LEAt(index);
}
inline uint16 getUint16BEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint16), uint16_can_only_be_read_from_int16_or_smaller_spans);
impl().validate(index, sizeof(uint16));
return READ_BE_UINT16(impl().data() + index);
}
inline uint16 getUint16LEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint16), uint16_can_only_be_read_from_int16_or_smaller_spans);
impl().validate(index, sizeof(uint16));
return READ_LE_UINT16(impl().data() + index);
}
inline uint32 getUint24LEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= 3, uint24_can_only_be_read_from_int24_or_smaller_spans);
impl().validate(index, 3);
return READ_LE_UINT24(impl().data() + index);
}
inline uint32 getUint32At(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint32), uint32_can_only_be_read_from_int32_or_smaller_spans);
impl().validate(index, sizeof(uint32));
return READ_UINT32(impl().data() + index);
}
inline int32 getInt32BEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint32), int32_can_only_be_read_from_int32_or_smaller_spans);
return (int32)impl().getUint32BEAt(index);
}
inline int32 getInt32LEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint32), int32_can_only_be_read_from_int32_or_smaller_spans);
return (int32)impl().getUint32LEAt(index);
}
inline uint32 getUint32BEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint32), uint32_can_only_be_read_from_int32_or_smaller_spans);
impl().validate(index, sizeof(uint32));
return READ_BE_UINT32(impl().data() + index);
}
inline uint32 getUint32LEAt(const index_type index) const {
STATIC_ASSERT(sizeof(value_type) <= sizeof(uint32), uint32_can_only_be_read_from_int32_or_smaller_spans);
impl().validate(index, sizeof(uint32));
return READ_LE_UINT32(impl().data() + index);
}
inline String getStringAt(const index_type index, size_type numEntries = kSpanMaxSize) const {
STATIC_ASSERT(sizeof(value_type) == sizeof(char), strings_can_only_be_read_from_byte_or_char_spans);
const char *string = (const char *)impl().data() + index;
if (numEntries == kSpanMaxSize) {
numEntries = strnlen(string, impl().size() - index);
}
impl().validate(index, numEntries);
return String(string, 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 * sizeof(value_type));
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 * sizeof(value_type));
return impl().data() + index;
}
inline MemoryReadStream toStream(const index_type index = 0, size_type numEntries = kSpanMaxSize) const {
if (numEntries == kSpanMaxSize) {
numEntries = impl().size() - index;
}
impl().validate(index, numEntries * sizeof(value_type));
return MemoryReadStream(impl().data() + index, numEntries * sizeof(value_type), 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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#endif
/**
* @returns true if bounds are invalid.
*/
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 {
/* LCOV_EXCL_START */
if (impl().checkInvalidBounds(index, deltaInBytes)) {
error("%s", impl().getValidationMessage(index, deltaInBytes, mode).c_str());
}
/* LCOV_EXCL_STOP */
}
};
#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:
COMMON_SPAN_TYPEDEFS
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()) {}
inline void clear() {
_data = nullptr;
_size = 0;
}
inline size_type size() const { return _size; }
inline pointer data() const { 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 = "unknown";
switch (mode) {
case kValidateRead:
modeName = "reading";
break;
case kValidateWrite:
modeName = "writing";
break;
case kValidateSeek:
modeName = "seeking";
break;
default:
break;
}
return String::format("Access violation %s %s: %u + %d > %u",
modeName,
this->impl().name().c_str(),
index,
deltaInBytes / (int)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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#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);
}
const uint32 bytesRequested = numEntries * sizeof(value_type);
assert(stream.pos() + bytesRequested <= (uint)stream.size());
allocate(numEntries);
const uint32 bytesRead = stream.read((void *)const_cast<mutable_value_type *>(_data), bytesRequested);
assert(bytesRead == bytesRequested);
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:
COMMON_SPAN_TYPEDEFS
inline Span() : super_type() {}
inline Span(const pointer data_, const size_type size_) : super_type(data_, size_) {}
// Allows unrelated sibling classes like NamedSpan to assign to superclass
// siblings like Span
template <typename Other>
inline Span(const Other &other) : super_type(other) {}
};
#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:
COMMON_SPAN_TYPEDEFS
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 Other>
inline NamedSpanImpl(const Other &other) :
super_type(other),
_name(other.name()),
_sourceByteOffset(other.sourceByteOffset()) {}
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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#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: %u + %d > %u)",
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());
}
template <typename OtherValueType, template <typename> class OtherDerived>
mutable_value_derived_type &allocateFromSpan(const SpanImpl<OtherValueType, OtherDerived> &other) {
super_type::allocateFromSpan(other);
return (mutable_value_derived_type &)const_cast<Derived<value_type> &>(this->impl());
}
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, const 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;
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
template <typename T> friend class NamedSpan;
#endif
public:
COMMON_SPAN_TYPEDEFS
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) {}
};
#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;
typedef typename OwnedSpan::pointer pointer;
typedef typename OwnedSpan::reference reference;
typedef typename OwnedSpan::const_reference const_reference;
#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);
}
inline SpanOwner &operator=(const SpanOwner &other) {
if (this == &other) {
return *this;
}
delete[] const_cast<typename RemoveConst<value_type>::type *>(_span.data());
_span.clear();
// Allocating memory when copy-assigning 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) {
_span.allocateFromSpan(other._span);
}
return *this;
}
inline ~SpanOwner() {
delete[] const_cast<typename RemoveConst<value_type>::type *>(_span.data());
}
/**
* Transfers ownership of the Span from the other owner to this owner.
*/
inline SpanOwner &moveFrom(SpanOwner &other) {
if (this == &other) {
return *this;
}
delete[] const_cast<typename RemoveConst<value_type>::type *>(_span.data());
_span = other._span;
other.release();
return *this;
}
/**
* Releases the memory owned by this SpanOwner to the caller.
*/
inline pointer release() {
pointer 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(_MSC_VER)
#if !defined(__GNUC__) || GCC_ATLEAST(3, 0)
protected:
#endif
#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_reference operator[](const index_type index) const { return _span[index]; }
inline reference operator[](const index_type index) { return _span[index]; }
};
} // End of namespace Common
#endif