Commit fc6c7cac authored by Miguel Ojeda's avatar Miguel Ojeda
Browse files

rust: print: add `pr_cont!` macro 



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: default avatarAdam Bratschi-Kaye <ark.email@gmail.com>
Signed-off-by: default avatarAdam Bratschi-Kaye <ark.email@gmail.com>
Co-developed-by: default avatarWedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: default avatarWedson Almeida Filho <wedsonaf@gmail.com>
Co-developed-by: default avatarGary Guo <gary@garyguo.net>
Signed-off-by: default avatarGary Guo <gary@garyguo.net>
Reviewed-by: default avatarWei Liu <wei.liu@kernel.org>
Reviewed-by: default avatarSergio González Collado <sergio.collado@gmail.com>
Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent 4c7f9499

rust/kernel/print.rs

+63 −9
Original line number Diff line number Diff line
@@ -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)*)

    )

);