Commit fbd3199c authored by fengzch-das's avatar fengzch-das
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/*
* Copyright 2014 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef FLATBUFFERS_H_
#define FLATBUFFERS_H_
#include <algorithm>
// TODO: These includes are for mitigating the pains of users editing their
// source because they relied on flatbuffers.h to include everything for them.
#include "flatbuffers/array.h"
#include "flatbuffers/base.h"
#include "flatbuffers/buffer.h"
#include "flatbuffers/buffer_ref.h"
#include "flatbuffers/detached_buffer.h"
#include "flatbuffers/flatbuffer_builder.h"
#include "flatbuffers/stl_emulation.h"
#include "flatbuffers/string.h"
#include "flatbuffers/struct.h"
#include "flatbuffers/table.h"
#include "flatbuffers/vector.h"
#include "flatbuffers/vector_downward.h"
#include "flatbuffers/verifier.h"
namespace flatbuffers {
/// @brief This can compute the start of a FlatBuffer from a root pointer, i.e.
/// it is the opposite transformation of GetRoot().
/// This may be useful if you want to pass on a root and have the recipient
/// delete the buffer afterwards.
inline const uint8_t *GetBufferStartFromRootPointer(const void *root) {
auto table = reinterpret_cast<const Table *>(root);
auto vtable = table->GetVTable();
// Either the vtable is before the root or after the root.
auto start = (std::min)(vtable, reinterpret_cast<const uint8_t *>(root));
// Align to at least sizeof(uoffset_t).
start = reinterpret_cast<const uint8_t *>(reinterpret_cast<uintptr_t>(start) &
~(sizeof(uoffset_t) - 1));
// Additionally, there may be a file_identifier in the buffer, and the root
// offset. The buffer may have been aligned to any size between
// sizeof(uoffset_t) and FLATBUFFERS_MAX_ALIGNMENT (see "force_align").
// Sadly, the exact alignment is only known when constructing the buffer,
// since it depends on the presence of values with said alignment properties.
// So instead, we simply look at the next uoffset_t values (root,
// file_identifier, and alignment padding) to see which points to the root.
// None of the other values can "impersonate" the root since they will either
// be 0 or four ASCII characters.
static_assert(flatbuffers::kFileIdentifierLength == sizeof(uoffset_t),
"file_identifier is assumed to be the same size as uoffset_t");
for (auto possible_roots = FLATBUFFERS_MAX_ALIGNMENT / sizeof(uoffset_t) + 1;
possible_roots; possible_roots--) {
start -= sizeof(uoffset_t);
if (ReadScalar<uoffset_t>(start) + start ==
reinterpret_cast<const uint8_t *>(root))
return start;
}
// We didn't find the root, either the "root" passed isn't really a root,
// or the buffer is corrupt.
// Assert, because calling this function with bad data may cause reads
// outside of buffer boundaries.
FLATBUFFERS_ASSERT(false);
return nullptr;
}
/// @brief This return the prefixed size of a FlatBuffer.
template<typename SizeT = uoffset_t>
inline SizeT GetPrefixedSize(const uint8_t *buf) {
return ReadScalar<SizeT>(buf);
}
// Base class for native objects (FlatBuffer data de-serialized into native
// C++ data structures).
// Contains no functionality, purely documentative.
struct NativeTable {};
/// @brief Function types to be used with resolving hashes into objects and
/// back again. The resolver gets a pointer to a field inside an object API
/// object that is of the type specified in the schema using the attribute
/// `cpp_type` (it is thus important whatever you write to this address
/// matches that type). The value of this field is initially null, so you
/// may choose to implement a delayed binding lookup using this function
/// if you wish. The resolver does the opposite lookup, for when the object
/// is being serialized again.
typedef uint64_t hash_value_t;
typedef std::function<void(void **pointer_adr, hash_value_t hash)>
resolver_function_t;
typedef std::function<hash_value_t(void *pointer)> rehasher_function_t;
// Helper function to test if a field is present, using any of the field
// enums in the generated code.
// `table` must be a generated table type. Since this is a template parameter,
// this is not typechecked to be a subclass of Table, so beware!
// Note: this function will return false for fields equal to the default
// value, since they're not stored in the buffer (unless force_defaults was
// used).
template<typename T>
bool IsFieldPresent(const T *table, typename T::FlatBuffersVTableOffset field) {
// Cast, since Table is a private baseclass of any table types.
return reinterpret_cast<const Table *>(table)->CheckField(
static_cast<voffset_t>(field));
}
// Utility function for reverse lookups on the EnumNames*() functions
// (in the generated C++ code)
// names must be NULL terminated.
inline int LookupEnum(const char **names, const char *name) {
for (const char **p = names; *p; p++)
if (!strcmp(*p, name)) return static_cast<int>(p - names);
return -1;
}
// These macros allow us to layout a struct with a guarantee that they'll end
// up looking the same on different compilers and platforms.
// It does this by disallowing the compiler to do any padding, and then
// does padding itself by inserting extra padding fields that make every
// element aligned to its own size.
// Additionally, it manually sets the alignment of the struct as a whole,
// which is typically its largest element, or a custom size set in the schema
// by the force_align attribute.
// These are used in the generated code only.
// clang-format off
#if defined(_MSC_VER)
#define FLATBUFFERS_MANUALLY_ALIGNED_STRUCT(alignment) \
__pragma(pack(1)) \
struct __declspec(align(alignment))
#define FLATBUFFERS_STRUCT_END(name, size) \
__pragma(pack()) \
static_assert(sizeof(name) == size, "compiler breaks packing rules")
#elif defined(__GNUC__) || defined(__clang__) || defined(__ICCARM__)
#define FLATBUFFERS_MANUALLY_ALIGNED_STRUCT(alignment) \
_Pragma("pack(1)") \
struct __attribute__((aligned(alignment)))
#define FLATBUFFERS_STRUCT_END(name, size) \
_Pragma("pack()") \
static_assert(sizeof(name) == size, "compiler breaks packing rules")
#else
#error Unknown compiler, please define structure alignment macros
#endif
// clang-format on
// Minimal reflection via code generation.
// Besides full-fat reflection (see reflection.h) and parsing/printing by
// loading schemas (see idl.h), we can also have code generation for minimal
// reflection data which allows pretty-printing and other uses without needing
// a schema or a parser.
// Generate code with --reflect-types (types only) or --reflect-names (names
// also) to enable.
// See minireflect.h for utilities using this functionality.
// These types are organized slightly differently as the ones in idl.h.
enum SequenceType { ST_TABLE, ST_STRUCT, ST_UNION, ST_ENUM };
// Scalars have the same order as in idl.h
// clang-format off
#define FLATBUFFERS_GEN_ELEMENTARY_TYPES(ET) \
ET(ET_UTYPE) \
ET(ET_BOOL) \
ET(ET_CHAR) \
ET(ET_UCHAR) \
ET(ET_SHORT) \
ET(ET_USHORT) \
ET(ET_INT) \
ET(ET_UINT) \
ET(ET_LONG) \
ET(ET_ULONG) \
ET(ET_FLOAT) \
ET(ET_DOUBLE) \
ET(ET_STRING) \
ET(ET_SEQUENCE) // See SequenceType.
enum ElementaryType {
#define FLATBUFFERS_ET(E) E,
FLATBUFFERS_GEN_ELEMENTARY_TYPES(FLATBUFFERS_ET)
#undef FLATBUFFERS_ET
};
inline const char * const *ElementaryTypeNames() {
static const char * const names[] = {
#define FLATBUFFERS_ET(E) #E,
FLATBUFFERS_GEN_ELEMENTARY_TYPES(FLATBUFFERS_ET)
#undef FLATBUFFERS_ET
};
return names;
}
// clang-format on
// Basic type info cost just 16bits per field!
// We're explicitly defining the signedness since the signedness of integer
// bitfields is otherwise implementation-defined and causes warnings on older
// GCC compilers.
struct TypeCode {
// ElementaryType
unsigned short base_type : 4;
// Either vector (in table) or array (in struct)
unsigned short is_repeating : 1;
// Index into type_refs below, or -1 for none.
signed short sequence_ref : 11;
};
static_assert(sizeof(TypeCode) == 2, "TypeCode");
struct TypeTable;
// Signature of the static method present in each type.
typedef const TypeTable *(*TypeFunction)();
struct TypeTable {
SequenceType st;
size_t num_elems; // of type_codes, values, names (but not type_refs).
const TypeCode *type_codes; // num_elems count
const TypeFunction *type_refs; // less than num_elems entries (see TypeCode).
const int16_t *array_sizes; // less than num_elems entries (see TypeCode).
const int64_t *values; // Only set for non-consecutive enum/union or structs.
const char *const *names; // Only set if compiled with --reflect-names.
};
// String which identifies the current version of FlatBuffers.
inline const char *flatbuffers_version_string() {
return "FlatBuffers " FLATBUFFERS_STRING(FLATBUFFERS_VERSION_MAJOR) "."
FLATBUFFERS_STRING(FLATBUFFERS_VERSION_MINOR) "."
FLATBUFFERS_STRING(FLATBUFFERS_VERSION_REVISION);
}
// clang-format off
#define FLATBUFFERS_DEFINE_BITMASK_OPERATORS(E, T)\
inline E operator | (E lhs, E rhs){\
return E(T(lhs) | T(rhs));\
}\
inline E operator & (E lhs, E rhs){\
return E(T(lhs) & T(rhs));\
}\
inline E operator ^ (E lhs, E rhs){\
return E(T(lhs) ^ T(rhs));\
}\
inline E operator ~ (E lhs){\
return E(~T(lhs));\
}\
inline E operator |= (E &lhs, E rhs){\
lhs = lhs | rhs;\
return lhs;\
}\
inline E operator &= (E &lhs, E rhs){\
lhs = lhs & rhs;\
return lhs;\
}\
inline E operator ^= (E &lhs, E rhs){\
lhs = lhs ^ rhs;\
return lhs;\
}\
inline bool operator !(E rhs) \
{\
return !bool(T(rhs)); \
}
/// @endcond
} // namespace flatbuffers
// clang-format on
#endif // FLATBUFFERS_H_
/*
* Copyright 2017 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef FLATBUFFERS_STL_EMULATION_H_
#define FLATBUFFERS_STL_EMULATION_H_
// clang-format off
#include "flatbuffers/base.h"
#include <string>
#include <type_traits>
#include <vector>
#include <memory>
#include <limits>
#ifndef FLATBUFFERS_USE_STD_OPTIONAL
// Detect C++17 compatible compiler.
// __cplusplus >= 201703L - a compiler has support of 'static inline' variables.
#if (defined(__cplusplus) && __cplusplus >= 201703L) \
|| (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)
#define FLATBUFFERS_USE_STD_OPTIONAL 1
#else
#define FLATBUFFERS_USE_STD_OPTIONAL 0
#endif // (defined(__cplusplus) && __cplusplus >= 201703L) ...
#endif // FLATBUFFERS_USE_STD_OPTIONAL
#if FLATBUFFERS_USE_STD_OPTIONAL
#include <optional>
#endif
#ifndef FLATBUFFERS_USE_STD_SPAN
// Testing __cpp_lib_span requires including either <version> or <span>,
// both of which were added in C++20.
// See: https://en.cppreference.com/w/cpp/utility/feature_test
#if defined(__cplusplus) && __cplusplus >= 202002L
#define FLATBUFFERS_USE_STD_SPAN 1
#endif
#endif // FLATBUFFERS_USE_STD_SPAN
#if defined(FLATBUFFERS_USE_STD_SPAN)
#include <array>
#include <span>
#else
// Disable non-trivial ctors if FLATBUFFERS_SPAN_MINIMAL defined.
#if !defined(FLATBUFFERS_TEMPLATES_ALIASES)
#define FLATBUFFERS_SPAN_MINIMAL
#else
// Enable implicit construction of a span<T,N> from a std::array<T,N>.
#include <array>
#endif
#endif // defined(FLATBUFFERS_USE_STD_SPAN)
// This header provides backwards compatibility for older versions of the STL.
namespace flatbuffers {
#if defined(FLATBUFFERS_TEMPLATES_ALIASES)
template <typename T>
using numeric_limits = std::numeric_limits<T>;
#else
template <typename T> class numeric_limits :
public std::numeric_limits<T> {};
#endif // defined(FLATBUFFERS_TEMPLATES_ALIASES)
#if defined(FLATBUFFERS_TEMPLATES_ALIASES)
template <typename T> using is_scalar = std::is_scalar<T>;
template <typename T, typename U> using is_same = std::is_same<T,U>;
template <typename T> using is_floating_point = std::is_floating_point<T>;
template <typename T> using is_unsigned = std::is_unsigned<T>;
template <typename T> using is_enum = std::is_enum<T>;
template <typename T> using make_unsigned = std::make_unsigned<T>;
template<bool B, class T, class F>
using conditional = std::conditional<B, T, F>;
template<class T, T v>
using integral_constant = std::integral_constant<T, v>;
template <bool B>
using bool_constant = integral_constant<bool, B>;
using true_type = std::true_type;
using false_type = std::false_type;
#else
// MSVC 2010 doesn't support C++11 aliases.
template <typename T> struct is_scalar : public std::is_scalar<T> {};
template <typename T, typename U> struct is_same : public std::is_same<T,U> {};
template <typename T> struct is_floating_point :
public std::is_floating_point<T> {};
template <typename T> struct is_unsigned : public std::is_unsigned<T> {};
template <typename T> struct is_enum : public std::is_enum<T> {};
template <typename T> struct make_unsigned : public std::make_unsigned<T> {};
template<bool B, class T, class F>
struct conditional : public std::conditional<B, T, F> {};
template<class T, T v>
struct integral_constant : public std::integral_constant<T, v> {};
template <bool B>
struct bool_constant : public integral_constant<bool, B> {};
typedef bool_constant<true> true_type;
typedef bool_constant<false> false_type;
#endif // defined(FLATBUFFERS_TEMPLATES_ALIASES)
#if defined(FLATBUFFERS_TEMPLATES_ALIASES)
template <class T> using unique_ptr = std::unique_ptr<T>;
#else
// MSVC 2010 doesn't support C++11 aliases.
// We're manually "aliasing" the class here as we want to bring unique_ptr
// into the flatbuffers namespace. We have unique_ptr in the flatbuffers
// namespace we have a completely independent implementation (see below)
// for C++98 STL implementations.
template <class T> class unique_ptr : public std::unique_ptr<T> {
public:
unique_ptr() {}
explicit unique_ptr(T* p) : std::unique_ptr<T>(p) {}
unique_ptr(std::unique_ptr<T>&& u) { *this = std::move(u); }
unique_ptr(unique_ptr&& u) { *this = std::move(u); }
unique_ptr& operator=(std::unique_ptr<T>&& u) {
std::unique_ptr<T>::reset(u.release());
return *this;
}
unique_ptr& operator=(unique_ptr&& u) {
std::unique_ptr<T>::reset(u.release());
return *this;
}
unique_ptr& operator=(T* p) {
return std::unique_ptr<T>::operator=(p);
}
};
#endif // defined(FLATBUFFERS_TEMPLATES_ALIASES)
#if FLATBUFFERS_USE_STD_OPTIONAL
template<class T>
using Optional = std::optional<T>;
using nullopt_t = std::nullopt_t;
inline constexpr nullopt_t nullopt = std::nullopt;
#else
// Limited implementation of Optional<T> type for a scalar T.
// This implementation limited by trivial types compatible with
// std::is_arithmetic<T> or std::is_enum<T> type traits.
// A tag to indicate an empty flatbuffers::optional<T>.
struct nullopt_t {
explicit FLATBUFFERS_CONSTEXPR_CPP11 nullopt_t(int) {}
};
#if defined(FLATBUFFERS_CONSTEXPR_DEFINED)
namespace internal {
template <class> struct nullopt_holder {
static constexpr nullopt_t instance_ = nullopt_t(0);
};
template<class Dummy>
constexpr nullopt_t nullopt_holder<Dummy>::instance_;
}
static constexpr const nullopt_t &nullopt = internal::nullopt_holder<void>::instance_;
#else
namespace internal {
template <class> struct nullopt_holder {
static const nullopt_t instance_;
};
template<class Dummy>
const nullopt_t nullopt_holder<Dummy>::instance_ = nullopt_t(0);
}
static const nullopt_t &nullopt = internal::nullopt_holder<void>::instance_;
#endif
template<class T>
class Optional FLATBUFFERS_FINAL_CLASS {
// Non-scalar 'T' would extremely complicated Optional<T>.
// Use is_scalar<T> checking because flatbuffers flatbuffers::is_arithmetic<T>
// isn't implemented.
static_assert(flatbuffers::is_scalar<T>::value, "unexpected type T");
public:
~Optional() {}
FLATBUFFERS_CONSTEXPR_CPP11 Optional() FLATBUFFERS_NOEXCEPT
: value_(), has_value_(false) {}
FLATBUFFERS_CONSTEXPR_CPP11 Optional(nullopt_t) FLATBUFFERS_NOEXCEPT
: value_(), has_value_(false) {}
FLATBUFFERS_CONSTEXPR_CPP11 Optional(T val) FLATBUFFERS_NOEXCEPT
: value_(val), has_value_(true) {}
FLATBUFFERS_CONSTEXPR_CPP11 Optional(const Optional &other) FLATBUFFERS_NOEXCEPT
: value_(other.value_), has_value_(other.has_value_) {}
FLATBUFFERS_CONSTEXPR_CPP14 Optional &operator=(const Optional &other) FLATBUFFERS_NOEXCEPT {
value_ = other.value_;
has_value_ = other.has_value_;
return *this;
}
FLATBUFFERS_CONSTEXPR_CPP14 Optional &operator=(nullopt_t) FLATBUFFERS_NOEXCEPT {
value_ = T();
has_value_ = false;
return *this;
}
FLATBUFFERS_CONSTEXPR_CPP14 Optional &operator=(T val) FLATBUFFERS_NOEXCEPT {
value_ = val;
has_value_ = true;
return *this;
}
void reset() FLATBUFFERS_NOEXCEPT {
*this = nullopt;
}
void swap(Optional &other) FLATBUFFERS_NOEXCEPT {
std::swap(value_, other.value_);
std::swap(has_value_, other.has_value_);
}
FLATBUFFERS_CONSTEXPR_CPP11 FLATBUFFERS_EXPLICIT_CPP11 operator bool() const FLATBUFFERS_NOEXCEPT {
return has_value_;
}
FLATBUFFERS_CONSTEXPR_CPP11 bool has_value() const FLATBUFFERS_NOEXCEPT {
return has_value_;
}
FLATBUFFERS_CONSTEXPR_CPP11 const T& operator*() const FLATBUFFERS_NOEXCEPT {
return value_;
}
const T& value() const {
FLATBUFFERS_ASSERT(has_value());
return value_;
}
T value_or(T default_value) const FLATBUFFERS_NOEXCEPT {
return has_value() ? value_ : default_value;
}
private:
T value_;
bool has_value_;
};
template<class T>
FLATBUFFERS_CONSTEXPR_CPP11 bool operator==(const Optional<T>& opt, nullopt_t) FLATBUFFERS_NOEXCEPT {
return !opt;
}
template<class T>
FLATBUFFERS_CONSTEXPR_CPP11 bool operator==(nullopt_t, const Optional<T>& opt) FLATBUFFERS_NOEXCEPT {
return !opt;
}
template<class T, class U>
FLATBUFFERS_CONSTEXPR_CPP11 bool operator==(const Optional<T>& lhs, const U& rhs) FLATBUFFERS_NOEXCEPT {
return static_cast<bool>(lhs) && (*lhs == rhs);
}
template<class T, class U>
FLATBUFFERS_CONSTEXPR_CPP11 bool operator==(const T& lhs, const Optional<U>& rhs) FLATBUFFERS_NOEXCEPT {
return static_cast<bool>(rhs) && (lhs == *rhs);
}
template<class T, class U>
FLATBUFFERS_CONSTEXPR_CPP11 bool operator==(const Optional<T>& lhs, const Optional<U>& rhs) FLATBUFFERS_NOEXCEPT {
return static_cast<bool>(lhs) != static_cast<bool>(rhs)
? false
: !static_cast<bool>(lhs) ? false : (*lhs == *rhs);
}
#endif // FLATBUFFERS_USE_STD_OPTIONAL
// Very limited and naive partial implementation of C++20 std::span<T,Extent>.
#if defined(FLATBUFFERS_USE_STD_SPAN)
inline constexpr std::size_t dynamic_extent = std::dynamic_extent;
template<class T, std::size_t Extent = std::dynamic_extent>
using span = std::span<T, Extent>;
#else // !defined(FLATBUFFERS_USE_STD_SPAN)
FLATBUFFERS_CONSTEXPR std::size_t dynamic_extent = static_cast<std::size_t>(-1);
// Exclude this code if MSVC2010 or non-STL Android is active.
// The non-STL Android doesn't have `std::is_convertible` required for SFINAE.
#if !defined(FLATBUFFERS_SPAN_MINIMAL)
namespace internal {
// This is SFINAE helper class for checking of a common condition:
// > This overload only participates in overload resolution
// > Check whether a pointer to an array of From can be converted
// > to a pointer to an array of To.
// This helper is used for checking of 'From -> const From'.
template<class To, std::size_t Extent, class From, std::size_t N>
struct is_span_convertible {
using type =
typename std::conditional<std::is_convertible<From (*)[], To (*)[]>::value
&& (Extent == dynamic_extent || N == Extent),
int, void>::type;
};
template<typename T>
struct SpanIterator {
// TODO: upgrade to std::random_access_iterator_tag.
using iterator_category = std::forward_iterator_tag;
using difference_type = std::ptrdiff_t;
using value_type = typename std::remove_cv<T>::type;
using reference = T&;
using pointer = T*;
// Convince MSVC compiler that this iterator is trusted (it is verified).
#ifdef _MSC_VER
using _Unchecked_type = pointer;
#endif // _MSC_VER
SpanIterator(pointer ptr) : ptr_(ptr) {}
reference operator*() const { return *ptr_; }
pointer operator->() { return ptr_; }
SpanIterator& operator++() { ptr_++; return *this; }
SpanIterator operator++(int) { auto tmp = *this; ++(*this); return tmp; }
friend bool operator== (const SpanIterator& lhs, const SpanIterator& rhs) { return lhs.ptr_ == rhs.ptr_; }
friend bool operator!= (const SpanIterator& lhs, const SpanIterator& rhs) { return lhs.ptr_ != rhs.ptr_; }
private:
pointer ptr_;
};
} // namespace internal
#endif // !defined(FLATBUFFERS_SPAN_MINIMAL)
// T - element type; must be a complete type that is not an abstract
// class type.
// Extent - the number of elements in the sequence, or dynamic.
template<class T, std::size_t Extent = dynamic_extent>
class span FLATBUFFERS_FINAL_CLASS {
public:
typedef T element_type;
typedef T& reference;
typedef const T& const_reference;
typedef T* pointer;
typedef const T* const_pointer;
typedef std::size_t size_type;
static FLATBUFFERS_CONSTEXPR size_type extent = Extent;
// Returns the number of elements in the span.
FLATBUFFERS_CONSTEXPR_CPP11 size_type size() const FLATBUFFERS_NOEXCEPT {
return count_;
}
// Returns the size of the sequence in bytes.
FLATBUFFERS_CONSTEXPR_CPP11
size_type size_bytes() const FLATBUFFERS_NOEXCEPT {
return size() * sizeof(element_type);
}
// Checks if the span is empty.
FLATBUFFERS_CONSTEXPR_CPP11 bool empty() const FLATBUFFERS_NOEXCEPT {
return size() == 0;
}
// Returns a pointer to the beginning of the sequence.
FLATBUFFERS_CONSTEXPR_CPP11 pointer data() const FLATBUFFERS_NOEXCEPT {
return data_;
}
#if !defined(FLATBUFFERS_SPAN_MINIMAL)
using Iterator = internal::SpanIterator<T>;
Iterator begin() const { return Iterator(data()); }
Iterator end() const { return Iterator(data() + size()); }
#endif
// Returns a reference to the idx-th element of the sequence.
// The behavior is undefined if the idx is greater than or equal to size().
FLATBUFFERS_CONSTEXPR_CPP11 reference operator[](size_type idx) const {
return data()[idx];
}
FLATBUFFERS_CONSTEXPR_CPP11 span(const span &other) FLATBUFFERS_NOEXCEPT
: data_(other.data_), count_(other.count_) {}
FLATBUFFERS_CONSTEXPR_CPP14 span &operator=(const span &other)
FLATBUFFERS_NOEXCEPT {
data_ = other.data_;
count_ = other.count_;
}
// Limited implementation of
// `template <class It> constexpr std::span(It first, size_type count);`.
//
// Constructs a span that is a view over the range [first, first + count);
// the resulting span has: data() == first and size() == count.
// The behavior is undefined if [first, first + count) is not a valid range,
// or if (extent != flatbuffers::dynamic_extent && count != extent).
FLATBUFFERS_CONSTEXPR_CPP11
explicit span(pointer first, size_type count) FLATBUFFERS_NOEXCEPT
: data_ (Extent == dynamic_extent ? first : (Extent == count ? first : nullptr)),
count_(Extent == dynamic_extent ? count : (Extent == count ? Extent : 0)) {
// Make span empty if the count argument is incompatible with span<T,N>.
}
// Exclude this code if MSVC2010 is active. The MSVC2010 isn't C++11
// compliant, it doesn't support default template arguments for functions.
#if defined(FLATBUFFERS_SPAN_MINIMAL)
FLATBUFFERS_CONSTEXPR_CPP11 span() FLATBUFFERS_NOEXCEPT : data_(nullptr),
count_(0) {
static_assert(extent == 0 || extent == dynamic_extent, "invalid span");
}
#else
// Constructs an empty span whose data() == nullptr and size() == 0.
// This overload only participates in overload resolution if
// extent == 0 || extent == flatbuffers::dynamic_extent.
// A dummy template argument N is need dependency for SFINAE.
template<std::size_t N = 0,
typename internal::is_span_convertible<element_type, Extent, element_type, (N - N)>::type = 0>
FLATBUFFERS_CONSTEXPR_CPP11 span() FLATBUFFERS_NOEXCEPT : data_(nullptr),
count_(0) {
static_assert(extent == 0 || extent == dynamic_extent, "invalid span");
}
// Constructs a span that is a view over the array arr; the resulting span
// has size() == N and data() == std::data(arr). These overloads only
// participate in overload resolution if
// extent == std::dynamic_extent || N == extent is true and
// std::remove_pointer_t<decltype(std::data(arr))>(*)[]
// is convertible to element_type (*)[].
template<std::size_t N,
typename internal::is_span_convertible<element_type, Extent, element_type, N>::type = 0>
FLATBUFFERS_CONSTEXPR_CPP11 span(element_type (&arr)[N]) FLATBUFFERS_NOEXCEPT
: data_(arr), count_(N) {}
template<class U, std::size_t N,
typename internal::is_span_convertible<element_type, Extent, U, N>::type = 0>
FLATBUFFERS_CONSTEXPR_CPP11 span(std::array<U, N> &arr) FLATBUFFERS_NOEXCEPT
: data_(arr.data()), count_(N) {}
//template<class U, std::size_t N,
// int = 0>
//FLATBUFFERS_CONSTEXPR_CPP11 span(std::array<U, N> &arr) FLATBUFFERS_NOEXCEPT
// : data_(arr.data()), count_(N) {}
template<class U, std::size_t N,
typename internal::is_span_convertible<element_type, Extent, U, N>::type = 0>
FLATBUFFERS_CONSTEXPR_CPP11 span(const std::array<U, N> &arr) FLATBUFFERS_NOEXCEPT
: data_(arr.data()), count_(N) {}
// Converting constructor from another span s;
// the resulting span has size() == s.size() and data() == s.data().
// This overload only participates in overload resolution
// if extent == std::dynamic_extent || N == extent is true and U (*)[]
// is convertible to element_type (*)[].
template<class U, std::size_t N,
typename internal::is_span_convertible<element_type, Extent, U, N>::type = 0>
FLATBUFFERS_CONSTEXPR_CPP11 span(const flatbuffers::span<U, N> &s) FLATBUFFERS_NOEXCEPT
: span(s.data(), s.size()) {
}
#endif // !defined(FLATBUFFERS_SPAN_MINIMAL)
private:
// This is a naive implementation with 'count_' member even if (Extent != dynamic_extent).
pointer const data_;
size_type count_;
};
#endif // defined(FLATBUFFERS_USE_STD_SPAN)
#if !defined(FLATBUFFERS_SPAN_MINIMAL)
template<class ElementType, std::size_t Extent>
FLATBUFFERS_CONSTEXPR_CPP11
flatbuffers::span<ElementType, Extent> make_span(ElementType(&arr)[Extent]) FLATBUFFERS_NOEXCEPT {
return span<ElementType, Extent>(arr);
}
template<class ElementType, std::size_t Extent>
FLATBUFFERS_CONSTEXPR_CPP11
flatbuffers::span<const ElementType, Extent> make_span(const ElementType(&arr)[Extent]) FLATBUFFERS_NOEXCEPT {
return span<const ElementType, Extent>(arr);
}
template<class ElementType, std::size_t Extent>
FLATBUFFERS_CONSTEXPR_CPP11
flatbuffers::span<ElementType, Extent> make_span(std::array<ElementType, Extent> &arr) FLATBUFFERS_NOEXCEPT {
return span<ElementType, Extent>(arr);
}
template<class ElementType, std::size_t Extent>
FLATBUFFERS_CONSTEXPR_CPP11
flatbuffers::span<const ElementType, Extent> make_span(const std::array<ElementType, Extent> &arr) FLATBUFFERS_NOEXCEPT {
return span<const ElementType, Extent>(arr);
}
template<class ElementType, std::size_t Extent>
FLATBUFFERS_CONSTEXPR_CPP11
flatbuffers::span<ElementType, dynamic_extent> make_span(ElementType *first, std::size_t count) FLATBUFFERS_NOEXCEPT {
return span<ElementType, dynamic_extent>(first, count);
}
template<class ElementType, std::size_t Extent>
FLATBUFFERS_CONSTEXPR_CPP11
flatbuffers::span<const ElementType, dynamic_extent> make_span(const ElementType *first, std::size_t count) FLATBUFFERS_NOEXCEPT {
return span<const ElementType, dynamic_extent>(first, count);
}
#endif // !defined(FLATBUFFERS_SPAN_MINIMAL)
} // namespace flatbuffers
#endif // FLATBUFFERS_STL_EMULATION_H_
/*
* Copyright 2021 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef FLATBUFFERS_STRING_H_
#define FLATBUFFERS_STRING_H_
#include "flatbuffers/base.h"
#include "flatbuffers/vector.h"
namespace flatbuffers {
struct String : public Vector<char> {
const char *c_str() const { return reinterpret_cast<const char *>(Data()); }
std::string str() const { return std::string(c_str(), size()); }
// clang-format off
#ifdef FLATBUFFERS_HAS_STRING_VIEW
flatbuffers::string_view string_view() const {
return flatbuffers::string_view(c_str(), size());
}
#endif // FLATBUFFERS_HAS_STRING_VIEW
// clang-format on
bool operator<(const String &o) const {
return StringLessThan(this->data(), this->size(), o.data(), o.size());
}
};
// Convenience function to get std::string from a String returning an empty
// string on null pointer.
static inline std::string GetString(const String *str) {
return str ? str->str() : "";
}
// Convenience function to get char* from a String returning an empty string on
// null pointer.
static inline const char *GetCstring(const String *str) {
return str ? str->c_str() : "";
}
#ifdef FLATBUFFERS_HAS_STRING_VIEW
// Convenience function to get string_view from a String returning an empty
// string_view on null pointer.
static inline flatbuffers::string_view GetStringView(const String *str) {
return str ? str->string_view() : flatbuffers::string_view();
}
#endif // FLATBUFFERS_HAS_STRING_VIEW
} // namespace flatbuffers
#endif // FLATBUFFERS_STRING_H_
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