tpm2_protocol/macro/
enum.rs

1// SPDX-License-Identifier: MIT OR Apache-2.0
2// Copyright (c) 2025 Opinsys Oy
3// Copyright (c) 2024-2025 Jarkko Sakkinen
4
5//! The chain of `if`-statements is a deliberate design choice as patterns in
6//! a `match`-statement is too restricted for arbitrary expressions (e.g, see
7//! `TpmRc` for an example).
8
9#[macro_export]
10macro_rules! tpm_enum {
11    (@impl $(#[$enum_meta:meta])* $vis:vis enum $name:ident($wrapper:ty, $repr:ty) {
12        $(
13            $(#[$variant_meta:meta])*
14            ($variant:ident, $value:expr, $display:literal)
15        ),* $(,)?
16    }) => {
17        $(#[$enum_meta])*
18        #[repr($repr)]
19        $vis enum $name {
20            $(
21                $(#[$variant_meta])*
22                $variant = $value
23            ),*
24        }
25
26        impl TryFrom<$repr> for $name {
27            type Error = $crate::TpmProtocolError;
28
29            fn try_from(value: $repr) -> Result<Self, $crate::TpmProtocolError> {
30                match value {
31                    $(
32                        _ if value == $value => Ok(Self::$variant),
33                    )*
34                    _ => Err($crate::TpmProtocolError::VariantNotAvailable),
35                }
36            }
37        }
38
39        impl core::fmt::Display for $name {
40            fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
41                let s = match self {
42                    $(Self::$variant => $display),*
43                };
44                write!(f, "{}", s)
45            }
46        }
47
48        impl $crate::TpmSized for $name {
49            const SIZE: usize = core::mem::size_of::<$repr>();
50
51            fn len(&self) -> usize {
52                Self::SIZE
53            }
54        }
55
56        impl $crate::TpmMarshal for $name {
57            fn marshal(&self, writer: &mut $crate::TpmWriter) -> $crate::TpmResult<()> {
58                let value = <$wrapper>::from(*self as $repr);
59                $crate::TpmMarshal::marshal(&value, writer)
60            }
61        }
62
63        impl $crate::TpmUnmarshal for $name {
64            fn unmarshal(buf: &[u8]) -> $crate::TpmResult<(Self, &[u8])> {
65                let (val, buf) = <$wrapper as $crate::TpmUnmarshal>::unmarshal(buf)?;
66                let raw: $repr = val.into();
67                let enum_val = Self::try_from(raw)?;
68                Ok((enum_val, buf))
69            }
70        }
71    };
72
73    ($(#[$meta:meta])* $vis:vis enum $name:ident(TpmUint8) { $($rest:tt)* }) => {
74        tpm_enum!(@impl $(#[$meta])* $vis enum $name($crate::basic::TpmUint8, u8) { $($rest)* });
75    };
76    ($(#[$meta:meta])* $vis:vis enum $name:ident(TpmInt8) { $($rest:tt)* }) => {
77        tpm_enum!(@impl $(#[$meta])* $vis enum $name($crate::basic::TpmInt8, i8) { $($rest)* });
78    };
79    ($(#[$meta:meta])* $vis:vis enum $name:ident(TpmUint16) { $($rest:tt)* }) => {
80        tpm_enum!(@impl $(#[$meta])* $vis enum $name($crate::basic::TpmUint16, u16) { $($rest)* });
81    };
82    ($(#[$meta:meta])* $vis:vis enum $name:ident(TpmUint32) { $($rest:tt)* }) => {
83        tpm_enum!(@impl $(#[$meta])* $vis enum $name($crate::basic::TpmUint32, u32) { $($rest)* });
84    };
85    ($(#[$meta:meta])* $vis:vis enum $name:ident(TpmInt32) { $($rest:tt)* }) => {
86        tpm_enum!(@impl $(#[$meta])* $vis enum $name($crate::basic::TpmInt32, i32) { $($rest)* });
87    };
88    ($(#[$meta:meta])* $vis:vis enum $name:ident(TpmUint64) { $($rest:tt)* }) => {
89        tpm_enum!(@impl $(#[$meta])* $vis enum $name($crate::basic::TpmUint64, u64) { $($rest)* });
90    };
91}