pw_format_core/
pw_format_core.rs

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1// Copyright 2024 The Pigweed Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License"); you may not
4// use this file except in compliance with the License. You may obtain a copy of
5// the License at
6//
7//     https://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12// License for the specific language governing permissions and limitations under
13// the License.
14#![no_std]
15//! Core support code for code generated by `pw_format` macros
16//!
17//! The contents of this crate are primarily used by code which is generated
18//! by macros using `pw_format`.
19
20/// Trait used to produce printf style format strings for untyped format
21/// specifiers.
22///
23/// The const [`PrintfFormatter::FORMAT_ARG`] is used to provide the printf
24/// format specifier (i.e. the `d` in `%02d`) for a given type in Rust.  This
25/// must be const so that it can be used to build static const format strings at
26/// compile time.
27pub trait PrintfFormatter {
28    /// The format specifier for this type.
29    const FORMAT_ARG: &'static str;
30}
31
32/// Trait used to produce printf style format strings for hex formatted untyped
33/// format specifiers.
34///
35/// The const [`PrintfHexFormatter::FORMAT_ARG`] is used to provide the printf
36/// format specifier (i.e. the `x` in `%02x`) for a given type in Rust.  This
37/// must be const so that it can be used to build static const format strings at
38/// compile time.
39pub trait PrintfHexFormatter {
40    /// The format specifier for this type.
41    const FORMAT_ARG: &'static str;
42}
43
44/// Trait used to produce printf style format strings for upper case hex
45/// formatted untyped format specifiers.
46///
47/// The const [`PrintfUpperHexFormatter::FORMAT_ARG`] is used to provide the
48/// printf format specifier (i.e. the `x` in `%02x`) for a given type in Rust.
49/// This must be const so that it can be used to build static const format
50/// strings at compile time.
51pub trait PrintfUpperHexFormatter {
52    /// The format specifier for this type.
53    const FORMAT_ARG: &'static str;
54}
55
56/// A helper to declare a [`PrintfFormatter`] trait and optionally
57/// [`PrintfHexFormatter`] and [`PrintfUpperHexFormatter`] traits for a given
58/// type.
59macro_rules! declare_formatter {
60    ($ty:ty, $specifier:literal, $hex_specifier:literal, $upper_hex_specifier:literal) => {
61        impl PrintfFormatter for $ty {
62            const FORMAT_ARG: &'static str = $specifier;
63        }
64
65        impl PrintfHexFormatter for $ty {
66            const FORMAT_ARG: &'static str = $hex_specifier;
67        }
68
69        impl PrintfUpperHexFormatter for $ty {
70            const FORMAT_ARG: &'static str = $upper_hex_specifier;
71        }
72    };
73
74    ($ty:ty, $specifier:literal) => {
75        impl PrintfFormatter for $ty {
76            const FORMAT_ARG: &'static str = $specifier;
77        }
78    };
79}
80
81declare_formatter!(char, "c");
82declare_formatter!(u8, "d");
83declare_formatter!(i32, "d");
84declare_formatter!(u32, "u", "x", "X");
85declare_formatter!(i64, "d");
86declare_formatter!(u64, "u", "x", "X");
87declare_formatter!(usize, "u", "x", "X");
88declare_formatter!(&str, "s");
pw_format_core/pw_format_core.rs

pw_format_core/
pw_format_core.rs
