626172a16b
Source files in libcamera start by a comment block header, which
includes the file name and a one-line description of the file contents.
While the latter is useful to get a quick overview of the file contents
at a glance, the former is mostly a source of inconvenience. The name in
the comments can easily get out of sync with the file name when files
are renamed, and copy & paste during development have often lead to
incorrect names being used to start with.
Readers of the source code are expected to know which file they're
looking it. Drop the file name from the header comment block.
The change was generated with the following script:
----------------------------------------
dirs="include/libcamera src test utils"
declare -rA patterns=(
['c']=' \* '
['cpp']=' \* '
['h']=' \* '
['py']='# '
['sh']='# '
)
for ext in ${!patterns[@]} ; do
files=$(for dir in $dirs ; do find $dir -name "*.${ext}" ; done)
pattern=${patterns[${ext}]}
for file in $files ; do
name=$(basename ${file})
sed -i "s/^\(${pattern}\)${name} - /\1/" "$file"
done
done
----------------------------------------
This misses several files that are out of sync with the comment block
header. Those will be addressed separately and manually.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
422 lines
12 KiB
C++
422 lines
12 KiB
C++
/* SPDX-License-Identifier: LGPL-2.1-or-later */
|
|
/*
|
|
* Copyright (C) 2020, Google Inc.
|
|
*
|
|
* C++20 std::span<> implementation for C++11
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <array>
|
|
#include <iterator>
|
|
#include <limits>
|
|
#include <stddef.h>
|
|
#include <type_traits>
|
|
|
|
namespace libcamera {
|
|
|
|
static constexpr std::size_t dynamic_extent = std::numeric_limits<std::size_t>::max();
|
|
|
|
template<typename T, std::size_t Extent = dynamic_extent>
|
|
class Span;
|
|
|
|
namespace details {
|
|
|
|
template<typename U>
|
|
struct is_array : public std::false_type {
|
|
};
|
|
|
|
template<typename U, std::size_t N>
|
|
struct is_array<std::array<U, N>> : public std::true_type {
|
|
};
|
|
|
|
template<typename U>
|
|
struct is_span : public std::false_type {
|
|
};
|
|
|
|
template<typename U, std::size_t Extent>
|
|
struct is_span<Span<U, Extent>> : public std::true_type {
|
|
};
|
|
|
|
} /* namespace details */
|
|
|
|
namespace utils {
|
|
|
|
template<typename C>
|
|
constexpr auto size(const C &c) -> decltype(c.size())
|
|
{
|
|
return c.size();
|
|
}
|
|
|
|
template<typename C>
|
|
constexpr auto data(const C &c) -> decltype(c.data())
|
|
{
|
|
return c.data();
|
|
}
|
|
|
|
template<typename C>
|
|
constexpr auto data(C &c) -> decltype(c.data())
|
|
{
|
|
return c.data();
|
|
}
|
|
|
|
template<class T, std::size_t N>
|
|
constexpr T *data(T (&array)[N]) noexcept
|
|
{
|
|
return array;
|
|
}
|
|
|
|
template<std::size_t I, typename T>
|
|
struct tuple_element;
|
|
|
|
template<std::size_t I, typename T, std::size_t N>
|
|
struct tuple_element<I, Span<T, N>> {
|
|
using type = T;
|
|
};
|
|
|
|
template<typename T>
|
|
struct tuple_size;
|
|
|
|
template<typename T, std::size_t N>
|
|
struct tuple_size<Span<T, N>> : public std::integral_constant<std::size_t, N> {
|
|
};
|
|
|
|
template<typename T>
|
|
struct tuple_size<Span<T, dynamic_extent>>;
|
|
|
|
} /* namespace utils */
|
|
|
|
template<typename T, std::size_t Extent>
|
|
class Span
|
|
{
|
|
public:
|
|
using element_type = T;
|
|
using value_type = typename std::remove_cv_t<T>;
|
|
using size_type = std::size_t;
|
|
using difference_type = std::ptrdiff_t;
|
|
using pointer = T *;
|
|
using const_pointer = const T *;
|
|
using reference = T &;
|
|
using const_reference = const T &;
|
|
using iterator = pointer;
|
|
using const_iterator = const_pointer;
|
|
using reverse_iterator = std::reverse_iterator<iterator>;
|
|
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
|
|
|
|
static constexpr std::size_t extent = Extent;
|
|
|
|
template<bool Dependent = false,
|
|
typename = std::enable_if_t<Dependent || Extent == 0>>
|
|
constexpr Span() noexcept
|
|
: data_(nullptr)
|
|
{
|
|
}
|
|
|
|
explicit constexpr Span(pointer ptr, [[maybe_unused]] size_type count)
|
|
: data_(ptr)
|
|
{
|
|
}
|
|
|
|
explicit constexpr Span(pointer first, [[maybe_unused]] pointer last)
|
|
: data_(first)
|
|
{
|
|
}
|
|
|
|
template<std::size_t N>
|
|
constexpr Span(element_type (&arr)[N],
|
|
std::enable_if_t<std::is_convertible<std::remove_pointer_t<decltype(utils::data(arr))> (*)[],
|
|
element_type (*)[]>::value &&
|
|
N == Extent,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(arr)
|
|
{
|
|
}
|
|
|
|
template<std::size_t N>
|
|
constexpr Span(std::array<value_type, N> &arr,
|
|
std::enable_if_t<std::is_convertible<std::remove_pointer_t<decltype(utils::data(arr))> (*)[],
|
|
element_type (*)[]>::value &&
|
|
N == Extent,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(arr.data())
|
|
{
|
|
}
|
|
|
|
template<std::size_t N>
|
|
constexpr Span(const std::array<value_type, N> &arr,
|
|
std::enable_if_t<std::is_convertible<std::remove_pointer_t<decltype(utils::data(arr))> (*)[],
|
|
element_type (*)[]>::value &&
|
|
N == Extent,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(arr.data())
|
|
{
|
|
}
|
|
|
|
template<class Container>
|
|
explicit constexpr Span(Container &cont,
|
|
std::enable_if_t<!details::is_span<Container>::value &&
|
|
!details::is_array<Container>::value &&
|
|
!std::is_array<Container>::value &&
|
|
std::is_convertible<std::remove_pointer_t<decltype(utils::data(cont))> (*)[],
|
|
element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr)
|
|
: data_(utils::data(cont))
|
|
{
|
|
}
|
|
|
|
template<class Container>
|
|
explicit constexpr Span(const Container &cont,
|
|
std::enable_if_t<!details::is_span<Container>::value &&
|
|
!details::is_array<Container>::value &&
|
|
!std::is_array<Container>::value &&
|
|
std::is_convertible<std::remove_pointer_t<decltype(utils::data(cont))> (*)[],
|
|
element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr)
|
|
: data_(utils::data(cont))
|
|
{
|
|
static_assert(utils::size(cont) == Extent, "Size mismatch");
|
|
}
|
|
|
|
template<class U, std::size_t N>
|
|
explicit constexpr Span(const Span<U, N> &s,
|
|
std::enable_if_t<std::is_convertible<U (*)[], element_type (*)[]>::value &&
|
|
N == Extent,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(s.data())
|
|
{
|
|
}
|
|
|
|
constexpr Span(const Span &other) noexcept = default;
|
|
constexpr Span &operator=(const Span &other) noexcept = default;
|
|
|
|
constexpr iterator begin() const { return data(); }
|
|
constexpr const_iterator cbegin() const { return begin(); }
|
|
constexpr iterator end() const { return data() + size(); }
|
|
constexpr const_iterator cend() const { return end(); }
|
|
constexpr reverse_iterator rbegin() const { return reverse_iterator(end()); }
|
|
constexpr const_reverse_iterator crbegin() const { return rbegin(); }
|
|
constexpr reverse_iterator rend() const { return reverse_iterator(begin()); }
|
|
constexpr const_reverse_iterator crend() const { return rend(); }
|
|
|
|
constexpr reference front() const { return *data(); }
|
|
constexpr reference back() const { return *(data() + size() - 1); }
|
|
constexpr reference operator[](size_type idx) const { return data()[idx]; }
|
|
constexpr pointer data() const noexcept { return data_; }
|
|
|
|
constexpr size_type size() const noexcept { return Extent; }
|
|
constexpr size_type size_bytes() const noexcept { return size() * sizeof(element_type); }
|
|
constexpr bool empty() const noexcept { return size() == 0; }
|
|
|
|
template<std::size_t Count>
|
|
constexpr Span<element_type, Count> first() const
|
|
{
|
|
static_assert(Count <= Extent, "Count larger than size");
|
|
return Span<element_type, Count>{ data(), Count };
|
|
}
|
|
|
|
constexpr Span<element_type, dynamic_extent> first(std::size_t Count) const
|
|
{
|
|
return Span<element_type, dynamic_extent>{ data(), Count };
|
|
}
|
|
|
|
template<std::size_t Count>
|
|
constexpr Span<element_type, Count> last() const
|
|
{
|
|
static_assert(Count <= Extent, "Count larger than size");
|
|
return Span<element_type, Count>{ data() + size() - Count, Count };
|
|
}
|
|
|
|
constexpr Span<element_type, dynamic_extent> last(std::size_t Count) const
|
|
{
|
|
return Span<element_type, dynamic_extent>{ data() + size() - Count, Count };
|
|
}
|
|
|
|
template<std::size_t Offset, std::size_t Count = dynamic_extent>
|
|
constexpr Span<element_type, Count != dynamic_extent ? Count : Extent - Offset> subspan() const
|
|
{
|
|
static_assert(Offset <= Extent, "Offset larger than size");
|
|
static_assert(Count == dynamic_extent || Count + Offset <= Extent,
|
|
"Offset + Count larger than size");
|
|
return Span<element_type, Count != dynamic_extent ? Count : Extent - Offset>{
|
|
data() + Offset,
|
|
Count == dynamic_extent ? size() - Offset : Count
|
|
};
|
|
}
|
|
|
|
constexpr Span<element_type, dynamic_extent>
|
|
subspan(std::size_t Offset, std::size_t Count = dynamic_extent) const
|
|
{
|
|
return Span<element_type, dynamic_extent>{
|
|
data() + Offset,
|
|
Count == dynamic_extent ? size() - Offset : Count
|
|
};
|
|
}
|
|
|
|
private:
|
|
pointer data_;
|
|
};
|
|
|
|
template<typename T>
|
|
class Span<T, dynamic_extent>
|
|
{
|
|
public:
|
|
using element_type = T;
|
|
using value_type = typename std::remove_cv_t<T>;
|
|
using size_type = std::size_t;
|
|
using difference_type = std::ptrdiff_t;
|
|
using pointer = T *;
|
|
using const_pointer = const T *;
|
|
using reference = T &;
|
|
using const_reference = const T &;
|
|
using iterator = T *;
|
|
using const_iterator = const T *;
|
|
using reverse_iterator = std::reverse_iterator<iterator>;
|
|
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
|
|
|
|
static constexpr std::size_t extent = dynamic_extent;
|
|
|
|
constexpr Span() noexcept
|
|
: data_(nullptr), size_(0)
|
|
{
|
|
}
|
|
|
|
constexpr Span(pointer ptr, size_type count)
|
|
: data_(ptr), size_(count)
|
|
{
|
|
}
|
|
|
|
constexpr Span(pointer first, pointer last)
|
|
: data_(first), size_(last - first)
|
|
{
|
|
}
|
|
|
|
template<std::size_t N>
|
|
constexpr Span(element_type (&arr)[N],
|
|
std::enable_if_t<std::is_convertible<std::remove_pointer_t<decltype(utils::data(arr))> (*)[],
|
|
element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(arr), size_(N)
|
|
{
|
|
}
|
|
|
|
template<std::size_t N>
|
|
constexpr Span(std::array<value_type, N> &arr,
|
|
std::enable_if_t<std::is_convertible<std::remove_pointer_t<decltype(utils::data(arr))> (*)[],
|
|
element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(utils::data(arr)), size_(N)
|
|
{
|
|
}
|
|
|
|
template<std::size_t N>
|
|
constexpr Span(const std::array<value_type, N> &arr) noexcept
|
|
: data_(utils::data(arr)), size_(N)
|
|
{
|
|
}
|
|
|
|
template<class Container>
|
|
constexpr Span(Container &cont,
|
|
std::enable_if_t<!details::is_span<Container>::value &&
|
|
!details::is_array<Container>::value &&
|
|
!std::is_array<Container>::value &&
|
|
std::is_convertible<std::remove_pointer_t<decltype(utils::data(cont))> (*)[],
|
|
element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr)
|
|
: data_(utils::data(cont)), size_(utils::size(cont))
|
|
{
|
|
}
|
|
|
|
template<class Container>
|
|
constexpr Span(const Container &cont,
|
|
std::enable_if_t<!details::is_span<Container>::value &&
|
|
!details::is_array<Container>::value &&
|
|
!std::is_array<Container>::value &&
|
|
std::is_convertible<std::remove_pointer_t<decltype(utils::data(cont))> (*)[],
|
|
element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr)
|
|
: data_(utils::data(cont)), size_(utils::size(cont))
|
|
{
|
|
}
|
|
|
|
template<class U, std::size_t N>
|
|
constexpr Span(const Span<U, N> &s,
|
|
std::enable_if_t<std::is_convertible<U (*)[], element_type (*)[]>::value,
|
|
std::nullptr_t> = nullptr) noexcept
|
|
: data_(s.data()), size_(s.size())
|
|
{
|
|
}
|
|
|
|
constexpr Span(const Span &other) noexcept = default;
|
|
|
|
constexpr Span &operator=(const Span &other) noexcept
|
|
{
|
|
data_ = other.data_;
|
|
size_ = other.size_;
|
|
return *this;
|
|
}
|
|
|
|
constexpr iterator begin() const { return data(); }
|
|
constexpr const_iterator cbegin() const { return begin(); }
|
|
constexpr iterator end() const { return data() + size(); }
|
|
constexpr const_iterator cend() const { return end(); }
|
|
constexpr reverse_iterator rbegin() const { return reverse_iterator(end()); }
|
|
constexpr const_reverse_iterator crbegin() const { return rbegin(); }
|
|
constexpr reverse_iterator rend() const { return reverse_iterator(begin()); }
|
|
constexpr const_reverse_iterator crend() const { return rend(); }
|
|
|
|
constexpr reference front() const { return *data(); }
|
|
constexpr reference back() const { return *(data() + size() - 1); }
|
|
constexpr reference operator[](size_type idx) const { return data()[idx]; }
|
|
constexpr pointer data() const noexcept { return data_; }
|
|
|
|
constexpr size_type size() const noexcept { return size_; }
|
|
constexpr size_type size_bytes() const noexcept { return size() * sizeof(element_type); }
|
|
constexpr bool empty() const noexcept { return size() == 0; }
|
|
|
|
template<std::size_t Count>
|
|
constexpr Span<element_type, Count> first() const
|
|
{
|
|
return Span<element_type, Count>{ data(), Count };
|
|
}
|
|
|
|
constexpr Span<element_type, dynamic_extent> first(std::size_t Count) const
|
|
{
|
|
return { data(), Count };
|
|
}
|
|
|
|
template<std::size_t Count>
|
|
constexpr Span<element_type, Count> last() const
|
|
{
|
|
return Span<element_type, Count>{ data() + size() - Count, Count };
|
|
}
|
|
|
|
constexpr Span<element_type, dynamic_extent> last(std::size_t Count) const
|
|
{
|
|
return Span<element_type, dynamic_extent>{ data() + size() - Count, Count };
|
|
}
|
|
|
|
template<std::size_t Offset, std::size_t Count = dynamic_extent>
|
|
constexpr Span<element_type, Count> subspan() const
|
|
{
|
|
return Span<element_type, Count>{
|
|
data() + Offset,
|
|
Count == dynamic_extent ? size() - Offset : Count
|
|
};
|
|
}
|
|
|
|
constexpr Span<element_type, dynamic_extent>
|
|
subspan(std::size_t Offset, std::size_t Count = dynamic_extent) const
|
|
{
|
|
return Span<element_type, dynamic_extent>{
|
|
data() + Offset,
|
|
Count == dynamic_extent ? size() - Offset : Count
|
|
};
|
|
}
|
|
|
|
private:
|
|
pointer data_;
|
|
size_type size_;
|
|
};
|
|
|
|
} /* namespace libcamera */
|