1// SPDX-License-Identifier: GPL-2.0
 2
 3//! Rust printing macros sample.
 4
 5use kernel::pr_cont;
 6use kernel::prelude::*;
 7
 8module! {
 9    type: RustPrint,
10    name: "rust_print",
11    author: "Rust for Linux Contributors",
12    description: "Rust printing macros sample",
13    license: "GPL",
14}
15
16struct RustPrint;
17
18#[expect(clippy::disallowed_macros)]
19fn arc_print() -> Result {
20    use kernel::sync::*;
21
22    let a = Arc::new(1, GFP_KERNEL)?;
23    let b = UniqueArc::new("hello, world", GFP_KERNEL)?;
24
25    // Prints the value of data in `a`.
26    pr_info!("{}", a);
27
28    // Uses ":?" to print debug fmt of `b`.
29    pr_info!("{:?}", b);
30
31    let a: Arc<&str> = b.into();
32    let c = a.clone();
33
34    // Uses `dbg` to print, will move `c` (for temporary debugging purposes).
35    dbg!(c);
36
37    // Pretty-prints the debug formatting with lower-case hexadecimal integers.
38    pr_info!("{:#x?}", a);
39
40    Ok(())
41}
42
43impl kernel::Module for RustPrint {
44    fn init(_module: &'static ThisModule) -> Result<Self> {
45        pr_info!("Rust printing macros sample (init)\n");
46
47        pr_emerg!("Emergency message (level 0) without args\n");
48        pr_alert!("Alert message (level 1) without args\n");
49        pr_crit!("Critical message (level 2) without args\n");
50        pr_err!("Error message (level 3) without args\n");
51        pr_warn!("Warning message (level 4) without args\n");
52        pr_notice!("Notice message (level 5) without args\n");
53        pr_info!("Info message (level 6) without args\n");
54
55        pr_info!("A line that");
56        pr_cont!(" is continued");
57        pr_cont!(" without args\n");
58
59        pr_emerg!("{} message (level {}) with args\n", "Emergency", 0);
60        pr_alert!("{} message (level {}) with args\n", "Alert", 1);
61        pr_crit!("{} message (level {}) with args\n", "Critical", 2);
62        pr_err!("{} message (level {}) with args\n", "Error", 3);
63        pr_warn!("{} message (level {}) with args\n", "Warning", 4);
64        pr_notice!("{} message (level {}) with args\n", "Notice", 5);
65        pr_info!("{} message (level {}) with args\n", "Info", 6);
66
67        pr_info!("A {} that", "line");
68        pr_cont!(" is {}", "continued");
69        pr_cont!(" with {}\n", "args");
70
71        arc_print()?;
72
73        trace::trace_rust_sample_loaded(42);
74
75        Ok(RustPrint)
76    }
77}
78
79impl Drop for RustPrint {
80    fn drop(&mut self) {
81        pr_info!("Rust printing macros sample (exit)\n");
82    }
83}
84
85mod trace {
86    use kernel::ffi::c_int;
87
88    kernel::declare_trace! {
89        /// # Safety
90        ///
91        /// Always safe to call.
92        unsafe fn rust_sample_loaded(magic: c_int);
93    }
94
95    pub(crate) fn trace_rust_sample_loaded(magic: i32) {
96        // SAFETY: Always safe to call.
97        unsafe { rust_sample_loaded(magic as c_int) }
98    }
99}