linux-support 0.0.25

// This file is part of linux-support. It is subject to the license terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/linux-support/master/COPYRIGHT. No part of linux-support, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
// Copyright © 2020 The developers of linux-support. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/linux-support/master/COPYRIGHT.


/// Command to get state of device's features
#[repr(C)]
#[derive(Default, Copy, Clone)]
pub(crate) struct ethtool_gfeatures
{
	/// Always `ETHTOOL_GFEATURES`.
	cmd: u32,
	
	/// On entry, the number of elements in the `features[]` array.
	/// On return, the number of elements in `features[]` needed to hold all features (`NETIF_F::ETHTOOL_DEV_FEATURE_WORDS`).
	///
	/// If `size` is not large enough, `EFAULT` is returned.
	size: u32,
	
	/// State of features.
	features: __IncompleteArrayField<ethtool_get_features_block>,
}

impl EthtoolCommand for ethtool_gfeatures
{
	#[inline(always)]
	fn command(&self) -> u32
	{
		self.cmd
	}
}

impl VariablySizedEthtoolCommand for ethtool_gfeatures
{
	type ArrayElement = ethtool_get_features_block;
	
	#[inline(always)]
	fn array_length(&self) -> u32
	{
		self.size
	}
}

impl VariablySizedEthtoolCommandWrapper<ethtool_gfeatures>
{
	/// Returns `true` if one or more features were added to `set_features`.
	pub(crate) fn change_features_if_possible(&self, features_to_change: &HashMap<NETIF_F, bool>, set_features: &mut VariablySizedEthtoolCommandWrapper<ethtool_sfeatures>) -> bool
	{
		let mut have_added_to_set_features = false;
		for (feature, desired_value) in features_to_change
		{
			let added_to_set_features = self.change_feature_if_possible(*feature, set_features, *desired_value);
			have_added_to_set_features |= added_to_set_features;
		}
		have_added_to_set_features
	}
	
	/// Returns `true` if the feature was added to `set_features`.
	pub(crate) fn change_feature_if_possible(&self, feature: NETIF_F, set_features: &mut VariablySizedEthtoolCommandWrapper<ethtool_sfeatures>, desired_value: bool) -> bool
	{
		if let Some(feature_value) = self.feature_is_available_and_can_be_changed_with_value(feature)
		{
			feature_value.update_if_desired(feature, set_features, desired_value)
		}
		else
		{
			false
		}
	}
	
	fn feature_is_available_and_can_be_changed_with_value(&self, feature: NETIF_F) -> Option<FeatureValue>
	{
		if self.feature_is_available_and_can_be_changed(feature)
		{
			Some
			(
				FeatureValue
				{
					requested: self.requested_is_set(feature),
					active: self.active_is_set(feature),
				}
			)
		}
		else
		{
			None
		}
	}
	
	#[inline(always)]
	fn feature_is_available_and_can_be_changed(&self, feature: NETIF_F) -> bool
	{
		self.available_is_set(feature) && !self.never_changed_is_set(feature)
	}
	
	#[inline(always)]
	pub(crate) fn available_features(&self) -> HashSet<NETIF_F>
	{
		self.features(Self::available_is_set)
	}
	
	#[inline(always)]
	pub(crate) fn requested_features(&self) -> HashSet<NETIF_F>
	{
		self.features(Self::requested_is_set)
	}
	
	#[inline(always)]
	pub(crate) fn active_features(&self) -> HashSet<NETIF_F>
	{
		self.features(Self::active_is_set)
	}
	
	#[inline(always)]
	pub(crate) fn never_changed_features(&self) -> HashSet<NETIF_F>
	{
		self.features(Self::never_changed_is_set)
	}
	
	#[inline(always)]
	fn features(&self, is_set: impl FnOnce(&Self, NETIF_F) -> bool + Copy) -> HashSet<NETIF_F>
	{
		let mut features = HashSet::with_capacity(NETIF_F::COUNT);
		for feature in NETIF_F::iter()
		{
			if is_set(self, feature)
			{
				features.insert(feature);
			}
		}
		features.shrink_to_fit();
		features
	}
	
	#[inline(always)]
	pub(crate) fn available_is_set(&self, feature: NETIF_F) -> bool
	{
		feature.is_set_field_locator(self.array_elements(), |ethtool_get_features_block| ethtool_get_features_block.available)
	}
	
	#[inline(always)]
	pub(crate) fn requested_is_set(&self, feature: NETIF_F) -> bool
	{
		feature.is_set_field_locator(self.array_elements(), |ethtool_get_features_block| ethtool_get_features_block.requested)
	}
	
	#[inline(always)]
	pub(crate) fn active_is_set(&self, feature: NETIF_F) -> bool
	{
		feature.is_set_field_locator(self.array_elements(), |ethtool_get_features_block| ethtool_get_features_block.active)
	}
	
	#[inline(always)]
	pub(crate) fn never_changed_is_set(&self, feature: NETIF_F) -> bool
	{
		feature.is_set_field_locator(self.array_elements(), |ethtool_get_features_block| ethtool_get_features_block.never_changed)
	}
}

impl ethtool_gfeatures
{
	#[inline(always)]
	pub(crate) fn new() -> VariablySizedEthtoolCommandWrapper<Self>
	{
		Self::new_with_initialized_header_but_uninitialized_array
		(
			Self
			{
				cmd: ETHTOOL_GFEATURES,
				size: NETIF_F::SafeSize as u32,
				features: __IncompleteArrayField::new(),
			}
		)
	}
}