xref: /openbmc/linux/samples/rust/rust_print.rs (revision 2a954832)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 //! Rust printing macros sample.
4 
5 use kernel::pr_cont;
6 use kernel::prelude::*;
7 
8 module! {
9     type: RustPrint,
10     name: "rust_print",
11     author: "Rust for Linux Contributors",
12     description: "Rust printing macros sample",
13     license: "GPL",
14 }
15 
16 struct RustPrint;
17 
18 fn arc_print() -> Result {
19     use kernel::sync::*;
20 
21     let a = Arc::try_new(1)?;
22     let b = UniqueArc::try_new("hello, world")?;
23 
24     // Prints the value of data in `a`.
25     pr_info!("{}", a);
26 
27     // Uses ":?" to print debug fmt of `b`.
28     pr_info!("{:?}", b);
29 
30     let a: Arc<&str> = b.into();
31     let c = a.clone();
32 
33     // Uses `dbg` to print, will move `c` (for temporary debugging purposes).
34     dbg!(c);
35 
36     // Pretty-prints the debug formatting with lower-case hexadecimal integers.
37     pr_info!("{:#x?}", a);
38 
39     Ok(())
40 }
41 
42 impl kernel::Module for RustPrint {
43     fn init(_module: &'static ThisModule) -> Result<Self> {
44         pr_info!("Rust printing macros sample (init)\n");
45 
46         pr_emerg!("Emergency message (level 0) without args\n");
47         pr_alert!("Alert message (level 1) without args\n");
48         pr_crit!("Critical message (level 2) without args\n");
49         pr_err!("Error message (level 3) without args\n");
50         pr_warn!("Warning message (level 4) without args\n");
51         pr_notice!("Notice message (level 5) without args\n");
52         pr_info!("Info message (level 6) without args\n");
53 
54         pr_info!("A line that");
55         pr_cont!(" is continued");
56         pr_cont!(" without args\n");
57 
58         pr_emerg!("{} message (level {}) with args\n", "Emergency", 0);
59         pr_alert!("{} message (level {}) with args\n", "Alert", 1);
60         pr_crit!("{} message (level {}) with args\n", "Critical", 2);
61         pr_err!("{} message (level {}) with args\n", "Error", 3);
62         pr_warn!("{} message (level {}) with args\n", "Warning", 4);
63         pr_notice!("{} message (level {}) with args\n", "Notice", 5);
64         pr_info!("{} message (level {}) with args\n", "Info", 6);
65 
66         pr_info!("A {} that", "line");
67         pr_cont!(" is {}", "continued");
68         pr_cont!(" with {}\n", "args");
69 
70         arc_print()?;
71 
72         Ok(RustPrint)
73     }
74 }
75 
76 impl Drop for RustPrint {
77     fn drop(&mut self) {
78         pr_info!("Rust printing macros sample (exit)\n");
79     }
80 }
81