From fc6c7cac83f05f455be1f35160a618e9df103838 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Thu, 10 Nov 2022 17:41:15 +0100 Subject: [PATCH] rust: print: add `pr_cont!` macro MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This level is a bit different from the rest since it does not pass the module name to the `_printk()` call. Thus add a new parameter to the general `print_macro!` to handle it differently. Co-developed-by: Adam Bratschi-Kaye Signed-off-by: Adam Bratschi-Kaye Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Gary Guo Signed-off-by: Gary Guo Reviewed-by: Wei Liu Reviewed-by: Sergio González Collado Signed-off-by: Miguel Ojeda --- rust/kernel/print.rs | 72 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 63 insertions(+), 9 deletions(-) diff --git a/rust/kernel/print.rs b/rust/kernel/print.rs index 694f51c6da5c..29bf9c2e8aee 100644 --- a/rust/kernel/print.rs +++ b/rust/kernel/print.rs @@ -81,6 +81,7 @@ pub mod format_strings { pub static NOTICE: [u8; LENGTH] = generate(false, bindings::KERN_NOTICE); pub static INFO: [u8; LENGTH] = generate(false, bindings::KERN_INFO); pub static DEBUG: [u8; LENGTH] = generate(false, bindings::KERN_DEBUG); + pub static CONT: [u8; LENGTH] = generate(true, bindings::KERN_CONT); } /// Prints a message via the kernel's [`_printk`]. @@ -111,6 +112,26 @@ pub unsafe fn call_printk( } } +/// Prints a message via the kernel's [`_printk`] for the `CONT` level. +/// +/// Public but hidden since it should only be used from public macros. +/// +/// [`_printk`]: ../../../../include/linux/printk.h +#[doc(hidden)] +#[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))] +pub fn call_printk_cont(args: fmt::Arguments<'_>) { + // `_printk` does not seem to fail in any path. + // + // SAFETY: The format string is fixed. + #[cfg(CONFIG_PRINTK)] + unsafe { + bindings::_printk( + format_strings::CONT.as_ptr() as _, + &args as *const _ as *const c_void, + ); + } +} + /// Performs formatting and forwards the string to [`call_printk`]. /// /// Public but hidden since it should only be used from public macros. @@ -120,7 +141,7 @@ pub unsafe fn call_printk( #[allow(clippy::crate_in_macro_def)] macro_rules! print_macro ( // The non-continuation cases (most of them, e.g. `INFO`). - ($format_string:path, $($arg:tt)+) => ( + ($format_string:path, false, $($arg:tt)+) => ( // SAFETY: This hidden macro should only be called by the documented // printing macros which ensure the format string is one of the fixed // ones. All `__LOG_PREFIX`s are null-terminated as they are generated @@ -134,6 +155,13 @@ macro_rules! print_macro ( ); } ); + + // The `CONT` case. + ($format_string:path, true, $($arg:tt)+) => ( + $crate::print::call_printk_cont( + format_args!($($arg)+), + ); + ); ); /// Stub for doctests @@ -174,7 +202,7 @@ macro_rules! print_macro ( #[macro_export] macro_rules! pr_emerg ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::EMERG, $($arg)*) + $crate::print_macro!($crate::print::format_strings::EMERG, false, $($arg)*) ) ); @@ -198,7 +226,7 @@ macro_rules! pr_emerg ( #[macro_export] macro_rules! pr_alert ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::ALERT, $($arg)*) + $crate::print_macro!($crate::print::format_strings::ALERT, false, $($arg)*) ) ); @@ -222,7 +250,7 @@ macro_rules! pr_alert ( #[macro_export] macro_rules! pr_crit ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::CRIT, $($arg)*) + $crate::print_macro!($crate::print::format_strings::CRIT, false, $($arg)*) ) ); @@ -246,7 +274,7 @@ macro_rules! pr_crit ( #[macro_export] macro_rules! pr_err ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::ERR, $($arg)*) + $crate::print_macro!($crate::print::format_strings::ERR, false, $($arg)*) ) ); @@ -270,7 +298,7 @@ macro_rules! pr_err ( #[macro_export] macro_rules! pr_warn ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::WARNING, $($arg)*) + $crate::print_macro!($crate::print::format_strings::WARNING, false, $($arg)*) ) ); @@ -294,7 +322,7 @@ macro_rules! pr_warn ( #[macro_export] macro_rules! pr_notice ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::NOTICE, $($arg)*) + $crate::print_macro!($crate::print::format_strings::NOTICE, false, $($arg)*) ) ); @@ -319,7 +347,7 @@ macro_rules! pr_notice ( #[doc(alias = "print")] macro_rules! pr_info ( ($($arg:tt)*) => ( - $crate::print_macro!($crate::print::format_strings::INFO, $($arg)*) + $crate::print_macro!($crate::print::format_strings::INFO, false, $($arg)*) ) ); @@ -346,7 +374,33 @@ macro_rules! pr_info ( macro_rules! pr_debug ( ($($arg:tt)*) => ( if cfg!(debug_assertions) { - $crate::print_macro!($crate::print::format_strings::DEBUG, $($arg)*) + $crate::print_macro!($crate::print::format_strings::DEBUG, false, $($arg)*) } ) ); + +/// Continues a previous log message in the same line. +/// +/// Use only when continuing a previous `pr_*!` macro (e.g. [`pr_info!`]). +/// +/// Equivalent to the kernel's [`pr_cont`] macro. +/// +/// Mimics the interface of [`std::print!`]. See [`core::fmt`] and +/// `alloc::format!` for information about the formatting syntax. +/// +/// [`pr_cont`]: https://www.kernel.org/doc/html/latest/core-api/printk-basics.html#c.pr_cont +/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html +/// +/// # Examples +/// +/// ``` +/// # use kernel::pr_cont; +/// pr_info!("hello"); +/// pr_cont!(" {}\n", "there"); +/// ``` +#[macro_export] +macro_rules! pr_cont ( + ($($arg:tt)*) => ( + $crate::print_macro!($crate::print::format_strings::CONT, true, $($arg)*) + ) +);