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// SPDX-License-Identifier: GPL-2.0
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// Copyright (C) 2025 Google LLC.
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use kernel::prelude::*;
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use crate::defs::*;
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pub(crate) type BinderResult<T = ()> = core::result::Result<T, BinderError>;
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/// An error that will be returned to userspace via the `BINDER_WRITE_READ` ioctl rather than via
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/// errno.
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pub(crate) struct BinderError {
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    pub(crate) reply: u32,
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    source: Option<Error>,
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}
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impl BinderError {
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    pub(crate) fn new_dead() -> Self {
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        Self {
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            reply: BR_DEAD_REPLY,
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            source: None,
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        }
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    }
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    pub(crate) fn new_frozen() -> Self {
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        Self {
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            reply: BR_FROZEN_REPLY,
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            source: None,
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        }
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    }
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    pub(crate) fn new_frozen_oneway() -> Self {
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        Self {
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            reply: BR_TRANSACTION_PENDING_FROZEN,
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            source: None,
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        }
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    }
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    pub(crate) fn is_dead(&self) -> bool {
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        self.reply == BR_DEAD_REPLY
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    }
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    pub(crate) fn as_errno(&self) -> kernel::ffi::c_int {
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        self.source.unwrap_or(EINVAL).to_errno()
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    }
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    pub(crate) fn should_pr_warn(&self) -> bool {
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        self.source.is_some()
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    }
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}
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/// Convert an errno into a `BinderError` and store the errno used to construct it. The errno
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/// should be stored as the thread's extended error when given to userspace.
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impl From<Error> for BinderError {
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    fn from(source: Error) -> Self {
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        Self {
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            reply: BR_FAILED_REPLY,
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            source: Some(source),
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        }
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    }
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}
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impl From<kernel::fs::file::BadFdError> for BinderError {
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    fn from(source: kernel::fs::file::BadFdError) -> Self {
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        BinderError::from(Error::from(source))
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    }
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}
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impl From<kernel::alloc::AllocError> for BinderError {
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    fn from(_: kernel::alloc::AllocError) -> Self {
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        Self {
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            reply: BR_FAILED_REPLY,
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            source: Some(ENOMEM),
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        }
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    }
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}
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impl core::fmt::Debug for BinderError {
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    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
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        match self.reply {
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            BR_FAILED_REPLY => match self.source.as_ref() {
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                Some(source) => f
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                    .debug_struct("BR_FAILED_REPLY")
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                    .field("source", source)
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                    .finish(),
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                None => f.pad("BR_FAILED_REPLY"),
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            },
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            BR_DEAD_REPLY => f.pad("BR_DEAD_REPLY"),
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            BR_FROZEN_REPLY => f.pad("BR_FROZEN_REPLY"),
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            BR_TRANSACTION_PENDING_FROZEN => f.pad("BR_TRANSACTION_PENDING_FROZEN"),
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            BR_TRANSACTION_COMPLETE => f.pad("BR_TRANSACTION_COMPLETE"),
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            _ => f
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                .debug_struct("BinderError")
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                .field("reply", &self.reply)
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                .finish(),
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        }
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    }
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}
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