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83 lines
2.1 KiB
Markdown
83 lines
2.1 KiB
Markdown
---
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title: "endian"
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---
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{{< callout type="info">}}
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Header: `endian.h`
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Since: `TBC`
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{{< /callout >}}
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Constants & utilities for endianess.
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For endian specific integral types, see `unaligned_type`.
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The values for endianness are dependant on the platform setup.
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If `ETL_ENDIAN_NATIVE` is defined by the user, then
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 `etl::endian::little = 0`
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 `etl::endian::big = 1`
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If `ETL_ENDIAN_NATIVE` is not defined by the user, then the ETL selects an appropriate definition.
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 If `ETL_CPP20_SUPPORTED == 1` and `ETL_USING_STL == 1` then
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  `etl::endian::little = std::endian::little`
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  `etl::endian::big = std::endian::big`
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  `etl::endian::native = std::endian::native`
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else if `__BYTE_ORDER__` is defined then
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 If `__ORDER_LITTLE_ENDIAN__` is defined then
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  `etl::endian::little = __ORDER_LITTLE_ENDIAN__`
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  `etl::endian::big = __ORDER_BIG_ENDIAN__`
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  `etl::endian::native = __BYTE_ORDER__`
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 else if `__LITTLE_ENDIAN__` is defined
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  `etl::endian::little = __LITTLE_ENDIAN__`
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  `etl::endian::big = __BIG_ENDIAN__`
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  `etl::endian::native = __BYTE_ORDER__`
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else
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The user needs to define `ETL_ENDIAN_NATIVE` either as `0` for little endian or `1` for big endian.
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## endian
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A smart enumeration defining little and big members.
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```cpp
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etl::endian::little;
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etl::endian::big;
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```
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## endianness
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Interrogates the endianness of the platform.
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```cpp
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etl::endian operator ()() const
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```
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`constexpr` if `ETL_CPP11_SUPPORTED == 1` and `ETL_ENDIAN_NATIVE` is defined.
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---
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```cpp
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operator etl::endian() const
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```
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`constexpr` if `ETL_CPP11_SUPPORTED == 1` and `ETL_ENDIAN_NATIVE` is defined.
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---
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```cpp
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static etl::endian value()
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```
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`constexpr` if `ETL_CPP11_SUPPORTED == 1` and `ETL_ENDIAN_NATIVE` is defined.
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## Host to network
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```cpp
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template <typename T>
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T hton(T value)
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```
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**Description**
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Converts `value` from host to network ordering.
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## Network to host
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```cpp
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template <typename T>
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T ntoh(T value)
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```
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**Description**
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Converts `value` from network to host ordering. |