* [PATCH v7 1/4] rust: move BStr,CStr Display impls behind method
2025-02-02 16:31 [PATCH v7 0/4] rust: replace kernel::str::CStr w/ core::ffi::CStr Tamir Duberstein
@ 2025-02-02 16:31 ` Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 2/4] rust: replace `CStr` with `core::ffi::CStr` Tamir Duberstein
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Tamir Duberstein @ 2025-02-02 16:31 UTC (permalink / raw)
To: Michal Rostecki, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Benno Lossin, Andreas Hindborg, Alice Ryhl,
Trevor Gross
Cc: rust-for-linux, linux-kernel, Tamir Duberstein
There are two reasons for doing this:
- Moving the Display impl behind a display method matches the style used
in the standard library for printing non-Unicode data.
- The standard library's core::ffi::CStr doesn't implement Display;
moving Display to a helper struct is a necessary step toward using it.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
rust/kernel/kunit.rs | 9 ++--
rust/kernel/str.rs | 121 +++++++++++++++++++++++++++++++++++----------------
2 files changed, 90 insertions(+), 40 deletions(-)
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 824da0e9738a..630b947c708c 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -56,6 +56,7 @@ macro_rules! kunit_assert {
break 'out;
}
+ static NAME: &'static $crate::str::CStr = $crate::c_str!($name);
static FILE: &'static $crate::str::CStr = $crate::c_str!($file);
static LINE: i32 = core::line!() as i32 - $diff;
static CONDITION: &'static $crate::str::CStr = $crate::c_str!(stringify!($condition));
@@ -71,11 +72,13 @@ macro_rules! kunit_assert {
//
// This mimics KUnit's failed assertion format.
$crate::kunit::err(format_args!(
- " # {}: ASSERTION FAILED at {FILE}:{LINE}\n",
- $name
+ " # {NAME}: ASSERTION FAILED at {FILE}:{LINE}\n",
+ NAME = NAME.display(),
+ FILE = FILE.display(),
));
$crate::kunit::err(format_args!(
- " Expected {CONDITION} to be true, but is false\n"
+ " Expected {CONDITION} to be true, but is false\n",
+ CONDITION = CONDITION.display(),
));
$crate::kunit::err(format_args!(
" Failure not reported to KUnit since this is a non-KUnit task\n"
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 28e2201604d6..c273f1367607 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -31,29 +31,77 @@ pub const fn from_bytes(bytes: &[u8]) -> &Self {
// SAFETY: `BStr` is transparent to `[u8]`.
unsafe { &*(bytes as *const [u8] as *const BStr) }
}
-}
-impl fmt::Display for BStr {
- /// Formats printable ASCII characters, escaping the rest.
+ /// Returns an object that implements [`Display`] for safely printing a [`BStr`] that may
+ /// contain non-Unicode data. If you would like an implementation which escapes the [`BStr`]
+ /// please use [`Debug`] instead.
+ ///
+ /// [`Display`]: fmt::Display
+ /// [`Debug`]: fmt::Debug
+ ///
+ /// # Examples
///
/// ```
- /// # use kernel::{fmt, b_str, str::{BStr, CString}};
+ /// # use kernel::{fmt, b_str, str::CString};
/// let ascii = b_str!("Hello, BStr!");
- /// let s = CString::try_from_fmt(fmt!("{}", ascii))?;
+ /// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
/// assert_eq!(s.as_bytes(), "Hello, BStr!".as_bytes());
///
/// let non_ascii = b_str!("🦀");
- /// let s = CString::try_from_fmt(fmt!("{}", non_ascii))?;
+ /// let s = CString::try_from_fmt(fmt!("{}", non_ascii.display()))?;
/// assert_eq!(s.as_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
/// ```
+ #[inline]
+ pub fn display(&self) -> Display<'_> {
+ Display {
+ inner: self,
+ escape_common: true,
+ }
+ }
+}
+
+/// Helper struct for safely printing a [`BStr`] with [`fmt!`] and `{}`.
+///
+/// A [`BStr`] might contain non-Unicode data. This `struct` implements the [`Display`] trait in a
+/// way that mitigates that. It is created by the [`display`](BStr::display) method on [`BStr`].
+///
+/// If you would like an implementation which escapes the string please use [`Debug`] instead.
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::{fmt, b_str, str::CString};
+/// let ascii = b_str!("Hello, BStr!");
+/// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
+/// assert_eq!(s.as_bytes(), "Hello, BStr!".as_bytes());
+///
+/// let non_ascii = b_str!("🦀");
+/// let s = CString::try_from_fmt(fmt!("{}", non_ascii.display()))?;
+/// assert_eq!(s.as_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());
+/// # Ok::<(), kernel::error::Error>(())
+/// ```
+///
+/// [`fmt!`]: crate::fmt
+/// [`Debug`]: fmt::Debug
+/// [`Display`]: fmt::Display
+pub struct Display<'a> {
+ inner: &'a BStr,
+ escape_common: bool,
+}
+
+impl fmt::Display for Display<'_> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
- for &b in &self.0 {
+ let Self {
+ inner: BStr(b),
+ escape_common,
+ } = self;
+ for &b in b {
match b {
// Common escape codes.
- b'\t' => f.write_str("\\t")?,
- b'\n' => f.write_str("\\n")?,
- b'\r' => f.write_str("\\r")?,
+ b'\t' if *escape_common => f.write_str("\\t")?,
+ b'\n' if *escape_common => f.write_str("\\n")?,
+ b'\r' if *escape_common => f.write_str("\\r")?,
// Printable characters.
0x20..=0x7e => f.write_char(b as char)?,
_ => write!(f, "\\x{:02x}", b)?,
@@ -68,7 +116,7 @@ impl fmt::Debug for BStr {
/// escaping the rest.
///
/// ```
- /// # use kernel::{fmt, b_str, str::{BStr, CString}};
+ /// # use kernel::{fmt, b_str, str::CString};
/// // Embedded double quotes are escaped.
/// let ascii = b_str!("Hello, \"BStr\"!");
/// let s = CString::try_from_fmt(fmt!("{:?}", ascii))?;
@@ -376,35 +424,35 @@ pub fn to_ascii_uppercase(&self) -> Result<CString, AllocError> {
Ok(s)
}
-}
-impl fmt::Display for CStr {
- /// Formats printable ASCII characters, escaping the rest.
+ /// Returns an object that implements [`Display`] for safely printing a [`CStr`] that may
+ /// contain non-Unicode data. If you would like an implementation which escapes the [`CStr`]
+ /// please use [`Debug`] instead.
+ ///
+ /// [`Display`]: fmt::Display
+ /// [`Debug`]: fmt::Debug
+ ///
+ /// # Examples
///
/// ```
/// # use kernel::c_str;
/// # use kernel::fmt;
- /// # use kernel::str::CStr;
/// # use kernel::str::CString;
/// let penguin = c_str!("🐧");
- /// let s = CString::try_from_fmt(fmt!("{}", penguin))?;
+ /// let s = CString::try_from_fmt(fmt!("{}", penguin.display()))?;
/// assert_eq!(s.as_bytes_with_nul(), "\\xf0\\x9f\\x90\\xa7\0".as_bytes());
///
/// let ascii = c_str!("so \"cool\"");
- /// let s = CString::try_from_fmt(fmt!("{}", ascii))?;
+ /// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
/// assert_eq!(s.as_bytes_with_nul(), "so \"cool\"\0".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
/// ```
- fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
- for &c in self.as_bytes() {
- if (0x20..0x7f).contains(&c) {
- // Printable character.
- f.write_char(c as char)?;
- } else {
- write!(f, "\\x{:02x}", c)?;
- }
+ #[inline]
+ pub fn display(&self) -> Display<'_> {
+ Display {
+ inner: self,
+ escape_common: false,
}
- Ok(())
}
}
@@ -414,7 +462,6 @@ impl fmt::Debug for CStr {
/// ```
/// # use kernel::c_str;
/// # use kernel::fmt;
- /// # use kernel::str::CStr;
/// # use kernel::str::CString;
/// let penguin = c_str!("🐧");
/// let s = CString::try_from_fmt(fmt!("{:?}", penguin))?;
@@ -595,13 +642,13 @@ fn test_cstr_as_str_unchecked() {
#[test]
fn test_cstr_display() {
let hello_world = CStr::from_bytes_with_nul(b"hello, world!\0").unwrap();
- assert_eq!(format!("{}", hello_world), "hello, world!");
+ assert_eq!(format!("{}", hello_world.display()), "hello, world!");
let non_printables = CStr::from_bytes_with_nul(b"\x01\x09\x0a\0").unwrap();
- assert_eq!(format!("{}", non_printables), "\\x01\\x09\\x0a");
+ assert_eq!(format!("{}", non_printables.display()), "\\x01\\x09\\x0a");
let non_ascii = CStr::from_bytes_with_nul(b"d\xe9j\xe0 vu\0").unwrap();
- assert_eq!(format!("{}", non_ascii), "d\\xe9j\\xe0 vu");
+ assert_eq!(format!("{}", non_ascii.display()), "d\\xe9j\\xe0 vu");
let good_bytes = CStr::from_bytes_with_nul(b"\xf0\x9f\xa6\x80\0").unwrap();
- assert_eq!(format!("{}", good_bytes), "\\xf0\\x9f\\xa6\\x80");
+ assert_eq!(format!("{}", good_bytes.display()), "\\xf0\\x9f\\xa6\\x80");
}
#[test]
@@ -612,7 +659,7 @@ fn test_cstr_display_all_bytes() {
bytes[i as usize] = i.wrapping_add(1);
}
let cstr = CStr::from_bytes_with_nul(&bytes).unwrap();
- assert_eq!(format!("{}", cstr), ALL_ASCII_CHARS);
+ assert_eq!(format!("{}", cstr.display()), ALL_ASCII_CHARS);
}
#[test]
@@ -630,15 +677,15 @@ fn test_cstr_debug() {
#[test]
fn test_bstr_display() {
let hello_world = BStr::from_bytes(b"hello, world!");
- assert_eq!(format!("{}", hello_world), "hello, world!");
+ assert_eq!(format!("{}", hello_world.display()), "hello, world!");
let escapes = BStr::from_bytes(b"_\t_\n_\r_\\_\'_\"_");
- assert_eq!(format!("{}", escapes), "_\\t_\\n_\\r_\\_'_\"_");
+ assert_eq!(format!("{}", escapes.display()), "_\\t_\\n_\\r_\\_'_\"_");
let others = BStr::from_bytes(b"\x01");
- assert_eq!(format!("{}", others), "\\x01");
+ assert_eq!(format!("{}", others.display()), "\\x01");
let non_ascii = BStr::from_bytes(b"d\xe9j\xe0 vu");
- assert_eq!(format!("{}", non_ascii), "d\\xe9j\\xe0 vu");
+ assert_eq!(format!("{}", non_ascii.display()), "d\\xe9j\\xe0 vu");
let good_bytes = BStr::from_bytes(b"\xf0\x9f\xa6\x80");
- assert_eq!(format!("{}", good_bytes), "\\xf0\\x9f\\xa6\\x80");
+ assert_eq!(format!("{}", good_bytes.display()), "\\xf0\\x9f\\xa6\\x80");
}
#[test]
--
2.48.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v7 2/4] rust: replace `CStr` with `core::ffi::CStr`
2025-02-02 16:31 [PATCH v7 0/4] rust: replace kernel::str::CStr w/ core::ffi::CStr Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 1/4] rust: move BStr,CStr Display impls behind method Tamir Duberstein
@ 2025-02-02 16:31 ` Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 3/4] rust: replace `kernel::c_str!` with C-Strings Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 4/4] rust: remove core::ffi::CStr reexport Tamir Duberstein
3 siblings, 0 replies; 5+ messages in thread
From: Tamir Duberstein @ 2025-02-02 16:31 UTC (permalink / raw)
To: Michal Rostecki, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Benno Lossin, Andreas Hindborg, Alice Ryhl,
Trevor Gross
Cc: rust-for-linux, linux-kernel, Tamir Duberstein
`std::ffi::CStr` was moved to `core::ffi::CStr` in Rust 1.64. Replace
`kernel::str::CStr` with `core::ffi::CStr` now that we can.
`kernel::str::CStr::{from,as}_char_ptr` live on as free functions in
`kernel::str` to paper over the difference between `core::ffi::c_char`
and `kernel::ffi::char`; see the code comment on the latter type for
details.
C-String literals were added in Rust 1.77. Opportunistically replace
instances of `kernel::c_str!` with C-String literals where other code
changes were already necessary; the rest will be done in a later commit.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
drivers/gpu/drm/drm_panic_qr.rs | 2 +-
rust/kernel/device.rs | 12 +-
rust/kernel/error.rs | 4 +-
rust/kernel/firmware.rs | 2 +-
rust/kernel/kunit.rs | 4 +-
rust/kernel/miscdevice.rs | 2 +-
rust/kernel/net/phy.rs | 2 +-
rust/kernel/of.rs | 2 +-
rust/kernel/pci.rs | 8 +-
rust/kernel/platform.rs | 2 +-
rust/kernel/prelude.rs | 5 +-
rust/kernel/seq_file.rs | 4 +-
rust/kernel/str.rs | 446 ++++++++++------------------------------
rust/kernel/sync/condvar.rs | 2 +-
rust/kernel/sync/lock.rs | 2 +-
rust/kernel/sync/lock/global.rs | 2 +-
rust/kernel/workqueue.rs | 2 +-
17 files changed, 138 insertions(+), 365 deletions(-)
diff --git a/drivers/gpu/drm/drm_panic_qr.rs b/drivers/gpu/drm/drm_panic_qr.rs
index bcf248f69252..ef294017888e 100644
--- a/drivers/gpu/drm/drm_panic_qr.rs
+++ b/drivers/gpu/drm/drm_panic_qr.rs
@@ -958,7 +958,7 @@ fn draw_all(&mut self, data: impl Iterator<Item = u8>) {
} else {
// SAFETY: The caller ensures that `url` is a valid pointer to a
// nul-terminated string.
- let url_cstr: &CStr = unsafe { CStr::from_char_ptr(url) };
+ let url_cstr: &CStr = unsafe { kernel::str::from_char_ptr(url) };
let segments = &[
&Segment::Binary(url_cstr.as_bytes()),
&Segment::Numeric(&data_slice[0..data_len]),
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index db2d9658ba47..9554921368c0 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -11,9 +11,6 @@
};
use core::{fmt, ptr};
-#[cfg(CONFIG_PRINTK)]
-use crate::c_str;
-
/// A reference-counted device.
///
/// This structure represents the Rust abstraction for a C `struct device`. This implementation
@@ -176,7 +173,7 @@ unsafe fn printk(&self, klevel: &[u8], msg: fmt::Arguments<'_>) {
bindings::_dev_printk(
klevel as *const _ as *const crate::ffi::c_char,
self.as_raw(),
- c_str!("%pA").as_char_ptr(),
+ crate::str::as_char_ptr(c"%pA"),
&msg as *const _ as *const crate::ffi::c_void,
)
};
@@ -185,7 +182,12 @@ unsafe fn printk(&self, klevel: &[u8], msg: fmt::Arguments<'_>) {
/// Checks if property is present or not.
pub fn property_present(&self, name: &CStr) -> bool {
// SAFETY: By the invariant of `CStr`, `name` is null-terminated.
- unsafe { bindings::device_property_present(self.as_raw().cast_const(), name.as_char_ptr()) }
+ unsafe {
+ bindings::device_property_present(
+ self.as_raw().cast_const(),
+ crate::str::as_char_ptr(name),
+ )
+ }
}
}
diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs
index f6ecf09cb65f..51c5e0f0a0bc 100644
--- a/rust/kernel/error.rs
+++ b/rust/kernel/error.rs
@@ -164,7 +164,7 @@ pub fn name(&self) -> Option<&'static CStr> {
None
} else {
// SAFETY: The string returned by `errname` is static and `NUL`-terminated.
- Some(unsafe { CStr::from_char_ptr(ptr) })
+ Some(unsafe { crate::str::from_char_ptr(ptr) })
}
}
@@ -187,7 +187,7 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
Some(name) => f
.debug_tuple(
// SAFETY: These strings are ASCII-only.
- unsafe { core::str::from_utf8_unchecked(name) },
+ unsafe { core::str::from_utf8_unchecked(name.to_bytes()) },
)
.finish(),
}
diff --git a/rust/kernel/firmware.rs b/rust/kernel/firmware.rs
index c5162fdc95ff..e75db4d825ce 100644
--- a/rust/kernel/firmware.rs
+++ b/rust/kernel/firmware.rs
@@ -61,7 +61,7 @@ fn request_internal(name: &CStr, dev: &Device, func: FwFunc) -> Result<Self> {
// SAFETY: `pfw` is a valid pointer to a NULL initialized `bindings::firmware` pointer.
// `name` and `dev` are valid as by their type invariants.
- let ret = unsafe { func.0(pfw as _, name.as_char_ptr(), dev.as_raw()) };
+ let ret = unsafe { func.0(pfw as _, crate::str::as_char_ptr(name), dev.as_raw()) };
if ret != 0 {
return Err(Error::from_errno(ret));
}
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 630b947c708c..9f40ea744fc2 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -101,12 +101,12 @@ unsafe impl Sync for Location {}
unsafe impl Sync for UnaryAssert {}
static LOCATION: Location = Location($crate::bindings::kunit_loc {
- file: FILE.as_char_ptr(),
+ file: $crate::str::as_char_ptr(FILE),
line: LINE,
});
static ASSERTION: UnaryAssert = UnaryAssert($crate::bindings::kunit_unary_assert {
assert: $crate::bindings::kunit_assert {},
- condition: CONDITION.as_char_ptr(),
+ condition: $crate::str::as_char_ptr(CONDITION),
expected_true: true,
});
diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
index e14433b2ab9d..65f70ff61eb3 100644
--- a/rust/kernel/miscdevice.rs
+++ b/rust/kernel/miscdevice.rs
@@ -34,7 +34,7 @@ pub const fn into_raw<T: MiscDevice>(self) -> bindings::miscdevice {
// SAFETY: All zeros is valid for this C type.
let mut result: bindings::miscdevice = unsafe { MaybeUninit::zeroed().assume_init() };
result.minor = bindings::MISC_DYNAMIC_MINOR as _;
- result.name = self.name.as_char_ptr();
+ result.name = crate::str::as_char_ptr(self.name);
result.fops = create_vtable::<T>();
result
}
diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs
index bb654a28dab3..c60205606aee 100644
--- a/rust/kernel/net/phy.rs
+++ b/rust/kernel/net/phy.rs
@@ -504,7 +504,7 @@ unsafe impl Sync for DriverVTable {}
pub const fn create_phy_driver<T: Driver>() -> DriverVTable {
// INVARIANT: All the fields of `struct phy_driver` are initialized properly.
DriverVTable(Opaque::new(bindings::phy_driver {
- name: T::NAME.as_char_ptr().cast_mut(),
+ name: crate::str::as_char_ptr(T::NAME),
flags: T::FLAGS,
phy_id: T::PHY_DEVICE_ID.id,
phy_id_mask: T::PHY_DEVICE_ID.mask_as_int(),
diff --git a/rust/kernel/of.rs b/rust/kernel/of.rs
index 04f2d8ef29cb..12ea65df46de 100644
--- a/rust/kernel/of.rs
+++ b/rust/kernel/of.rs
@@ -29,7 +29,7 @@ fn index(&self) -> usize {
impl DeviceId {
/// Create a new device id from an OF 'compatible' string.
pub const fn new(compatible: &'static CStr) -> Self {
- let src = compatible.as_bytes_with_nul();
+ let src = compatible.to_bytes_with_nul();
// Replace with `bindings::of_device_id::default()` once stabilized for `const`.
// SAFETY: FFI type is valid to be zero-initialized.
let mut of: bindings::of_device_id = unsafe { core::mem::zeroed() };
diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs
index 4c98b5b9aa1e..af36ddac80ff 100644
--- a/rust/kernel/pci.rs
+++ b/rust/kernel/pci.rs
@@ -35,7 +35,7 @@ unsafe fn register(
) -> Result {
// SAFETY: It's safe to set the fields of `struct pci_driver` on initialization.
unsafe {
- (*pdrv.get()).name = name.as_char_ptr();
+ (*pdrv.get()).name = crate::str::as_char_ptr(name);
(*pdrv.get()).probe = Some(Self::probe_callback);
(*pdrv.get()).remove = Some(Self::remove_callback);
(*pdrv.get()).id_table = T::ID_TABLE.as_ptr();
@@ -43,7 +43,7 @@ unsafe fn register(
// SAFETY: `pdrv` is guaranteed to be a valid `RegType`.
to_result(unsafe {
- bindings::__pci_register_driver(pdrv.get(), module.0, name.as_char_ptr())
+ bindings::__pci_register_driver(pdrv.get(), module.0, crate::str::as_char_ptr(name))
})
}
@@ -275,7 +275,9 @@ fn new(pdev: Device, num: u32, name: &CStr) -> Result<Self> {
// `pdev` is valid by the invariants of `Device`.
// `num` is checked for validity by a previous call to `Device::resource_len`.
// `name` is always valid.
- let ret = unsafe { bindings::pci_request_region(pdev.as_raw(), num, name.as_char_ptr()) };
+ let ret = unsafe {
+ bindings::pci_request_region(pdev.as_raw(), num, crate::str::as_char_ptr(name))
+ };
if ret != 0 {
return Err(EBUSY);
}
diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index 50e6b0421813..d1752a978af4 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -36,7 +36,7 @@ unsafe fn register(
// SAFETY: It's safe to set the fields of `struct platform_driver` on initialization.
unsafe {
- (*pdrv.get()).driver.name = name.as_char_ptr();
+ (*pdrv.get()).driver.name = crate::str::as_char_ptr(name);
(*pdrv.get()).probe = Some(Self::probe_callback);
(*pdrv.get()).remove = Some(Self::remove_callback);
(*pdrv.get()).driver.of_match_table = of_table;
diff --git a/rust/kernel/prelude.rs b/rust/kernel/prelude.rs
index dde2e0649790..96e7029c27da 100644
--- a/rust/kernel/prelude.rs
+++ b/rust/kernel/prelude.rs
@@ -34,7 +34,10 @@
pub use super::error::{code::*, Error, Result};
-pub use super::{str::CStr, ThisModule};
+pub use super::{
+ str::{CStr, CStrExt as _},
+ ThisModule,
+};
pub use super::init::{InPlaceInit, InPlaceWrite, Init, PinInit};
diff --git a/rust/kernel/seq_file.rs b/rust/kernel/seq_file.rs
index 04947c672979..bb3c49fd4ef3 100644
--- a/rust/kernel/seq_file.rs
+++ b/rust/kernel/seq_file.rs
@@ -4,7 +4,7 @@
//!
//! C header: [`include/linux/seq_file.h`](srctree/include/linux/seq_file.h)
-use crate::{bindings, c_str, types::NotThreadSafe, types::Opaque};
+use crate::{bindings, types::NotThreadSafe, types::Opaque};
/// A utility for generating the contents of a seq file.
#[repr(transparent)]
@@ -35,7 +35,7 @@ pub fn call_printf(&self, args: core::fmt::Arguments<'_>) {
unsafe {
bindings::seq_printf(
self.inner.get(),
- c_str!("%pA").as_char_ptr(),
+ crate::str::as_char_ptr(c"%pA"),
&args as *const _ as *const crate::ffi::c_void,
);
}
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index c273f1367607..0c4189a478b4 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -4,7 +4,7 @@
use crate::alloc::{flags::*, AllocError, KVec};
use core::fmt::{self, Write};
-use core::ops::{self, Deref, DerefMut, Index};
+use core::ops::{Deref, DerefMut};
use crate::error::{code::*, Error};
@@ -45,11 +45,11 @@ pub const fn from_bytes(bytes: &[u8]) -> &Self {
/// # use kernel::{fmt, b_str, str::CString};
/// let ascii = b_str!("Hello, BStr!");
/// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
- /// assert_eq!(s.as_bytes(), "Hello, BStr!".as_bytes());
+ /// assert_eq!(s.to_bytes(), "Hello, BStr!".as_bytes());
///
/// let non_ascii = b_str!("🦀");
/// let s = CString::try_from_fmt(fmt!("{}", non_ascii.display()))?;
- /// assert_eq!(s.as_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());
+ /// assert_eq!(s.to_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
/// ```
#[inline]
@@ -74,11 +74,11 @@ pub fn display(&self) -> Display<'_> {
/// # use kernel::{fmt, b_str, str::CString};
/// let ascii = b_str!("Hello, BStr!");
/// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
-/// assert_eq!(s.as_bytes(), "Hello, BStr!".as_bytes());
+/// assert_eq!(s.to_bytes(), "Hello, BStr!".as_bytes());
///
/// let non_ascii = b_str!("🦀");
/// let s = CString::try_from_fmt(fmt!("{}", non_ascii.display()))?;
-/// assert_eq!(s.as_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());
+/// assert_eq!(s.to_bytes(), "\\xf0\\x9f\\xa6\\x80".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
/// ```
///
@@ -120,11 +120,11 @@ impl fmt::Debug for BStr {
/// // Embedded double quotes are escaped.
/// let ascii = b_str!("Hello, \"BStr\"!");
/// let s = CString::try_from_fmt(fmt!("{:?}", ascii))?;
- /// assert_eq!(s.as_bytes(), "\"Hello, \\\"BStr\\\"!\"".as_bytes());
+ /// assert_eq!(s.to_bytes(), "\"Hello, \\\"BStr\\\"!\"".as_bytes());
///
/// let non_ascii = b_str!("😺");
/// let s = CString::try_from_fmt(fmt!("{:?}", non_ascii))?;
- /// assert_eq!(s.as_bytes(), "\"\\xf0\\x9f\\x98\\xba\"".as_bytes());
+ /// assert_eq!(s.to_bytes(), "\"\\xf0\\x9f\\x98\\xba\"".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
/// ```
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -177,190 +177,36 @@ macro_rules! b_str {
}};
}
-/// Possible errors when using conversion functions in [`CStr`].
-#[derive(Debug, Clone, Copy)]
-pub enum CStrConvertError {
- /// Supplied bytes contain an interior `NUL`.
- InteriorNul,
+pub use core::ffi::CStr;
- /// Supplied bytes are not terminated by `NUL`.
- NotNulTerminated,
+/// Wraps a raw C string with a safe C string wrapper.
+///
+/// # Safety
+///
+/// `ptr` must be a valid pointer to a `NUL`-terminated C string, and it must
+/// last at least `'a`. When `CStr` is alive, the memory pointed by `ptr`
+/// must not be mutated.
+// This function exists to paper over the fact that `CStr::from_ptr` takes a `*const
+// core::ffi::c_char` rather than a `*const crate::ffi::c_char`.
+#[inline]
+pub unsafe fn from_char_ptr<'a>(ptr: *const crate::ffi::c_char) -> &'a CStr {
+ // SAFETY: The safety preconditions are the same as for `CStr::from_ptr`.
+ unsafe { CStr::from_ptr(ptr.cast()) }
}
-impl From<CStrConvertError> for Error {
- #[inline]
- fn from(_: CStrConvertError) -> Error {
- EINVAL
- }
+/// Returns a C pointer to the string.
+// This function exists to paper over the fact that `CStr::as_ptr` returns a `*const
+// core::ffi::c_char` rather than a `*const crate::ffi::c_char`. It is a free function rather than a
+// method on an extension trait because:
+//
+// - error[E0379]: functions in trait impls cannot be declared const
+#[inline]
+pub const fn as_char_ptr(c_str: &CStr) -> *const crate::ffi::c_char {
+ c_str.as_ptr().cast()
}
-/// A string that is guaranteed to have exactly one `NUL` byte, which is at the
-/// end.
-///
-/// Used for interoperability with kernel APIs that take C strings.
-#[repr(transparent)]
-pub struct CStr([u8]);
-
-impl CStr {
- /// Returns the length of this string excluding `NUL`.
- #[inline]
- pub const fn len(&self) -> usize {
- self.len_with_nul() - 1
- }
-
- /// Returns the length of this string with `NUL`.
- #[inline]
- pub const fn len_with_nul(&self) -> usize {
- if self.0.is_empty() {
- // SAFETY: This is one of the invariant of `CStr`.
- // We add a `unreachable_unchecked` here to hint the optimizer that
- // the value returned from this function is non-zero.
- unsafe { core::hint::unreachable_unchecked() };
- }
- self.0.len()
- }
-
- /// Returns `true` if the string only includes `NUL`.
- #[inline]
- pub const fn is_empty(&self) -> bool {
- self.len() == 0
- }
-
- /// Wraps a raw C string pointer.
- ///
- /// # Safety
- ///
- /// `ptr` must be a valid pointer to a `NUL`-terminated C string, and it must
- /// last at least `'a`. When `CStr` is alive, the memory pointed by `ptr`
- /// must not be mutated.
- #[inline]
- pub unsafe fn from_char_ptr<'a>(ptr: *const crate::ffi::c_char) -> &'a Self {
- // SAFETY: The safety precondition guarantees `ptr` is a valid pointer
- // to a `NUL`-terminated C string.
- let len = unsafe { bindings::strlen(ptr) } + 1;
- // SAFETY: Lifetime guaranteed by the safety precondition.
- let bytes = unsafe { core::slice::from_raw_parts(ptr as _, len) };
- // SAFETY: As `len` is returned by `strlen`, `bytes` does not contain interior `NUL`.
- // As we have added 1 to `len`, the last byte is known to be `NUL`.
- unsafe { Self::from_bytes_with_nul_unchecked(bytes) }
- }
-
- /// Creates a [`CStr`] from a `[u8]`.
- ///
- /// The provided slice must be `NUL`-terminated, does not contain any
- /// interior `NUL` bytes.
- pub const fn from_bytes_with_nul(bytes: &[u8]) -> Result<&Self, CStrConvertError> {
- if bytes.is_empty() {
- return Err(CStrConvertError::NotNulTerminated);
- }
- if bytes[bytes.len() - 1] != 0 {
- return Err(CStrConvertError::NotNulTerminated);
- }
- let mut i = 0;
- // `i + 1 < bytes.len()` allows LLVM to optimize away bounds checking,
- // while it couldn't optimize away bounds checks for `i < bytes.len() - 1`.
- while i + 1 < bytes.len() {
- if bytes[i] == 0 {
- return Err(CStrConvertError::InteriorNul);
- }
- i += 1;
- }
- // SAFETY: We just checked that all properties hold.
- Ok(unsafe { Self::from_bytes_with_nul_unchecked(bytes) })
- }
-
- /// Creates a [`CStr`] from a `[u8]` without performing any additional
- /// checks.
- ///
- /// # Safety
- ///
- /// `bytes` *must* end with a `NUL` byte, and should only have a single
- /// `NUL` byte (or the string will be truncated).
- #[inline]
- pub const unsafe fn from_bytes_with_nul_unchecked(bytes: &[u8]) -> &CStr {
- // SAFETY: Properties of `bytes` guaranteed by the safety precondition.
- unsafe { core::mem::transmute(bytes) }
- }
-
- /// Creates a mutable [`CStr`] from a `[u8]` without performing any
- /// additional checks.
- ///
- /// # Safety
- ///
- /// `bytes` *must* end with a `NUL` byte, and should only have a single
- /// `NUL` byte (or the string will be truncated).
- #[inline]
- pub unsafe fn from_bytes_with_nul_unchecked_mut(bytes: &mut [u8]) -> &mut CStr {
- // SAFETY: Properties of `bytes` guaranteed by the safety precondition.
- unsafe { &mut *(bytes as *mut [u8] as *mut CStr) }
- }
-
- /// Returns a C pointer to the string.
- #[inline]
- pub const fn as_char_ptr(&self) -> *const crate::ffi::c_char {
- self.0.as_ptr()
- }
-
- /// Convert the string to a byte slice without the trailing `NUL` byte.
- #[inline]
- pub fn as_bytes(&self) -> &[u8] {
- &self.0[..self.len()]
- }
-
- /// Convert the string to a byte slice containing the trailing `NUL` byte.
- #[inline]
- pub const fn as_bytes_with_nul(&self) -> &[u8] {
- &self.0
- }
-
- /// Yields a [`&str`] slice if the [`CStr`] contains valid UTF-8.
- ///
- /// If the contents of the [`CStr`] are valid UTF-8 data, this
- /// function will return the corresponding [`&str`] slice. Otherwise,
- /// it will return an error with details of where UTF-8 validation failed.
- ///
- /// # Examples
- ///
- /// ```
- /// # use kernel::str::CStr;
- /// let cstr = CStr::from_bytes_with_nul(b"foo\0")?;
- /// assert_eq!(cstr.to_str(), Ok("foo"));
- /// # Ok::<(), kernel::error::Error>(())
- /// ```
- #[inline]
- pub fn to_str(&self) -> Result<&str, core::str::Utf8Error> {
- core::str::from_utf8(self.as_bytes())
- }
-
- /// Unsafely convert this [`CStr`] into a [`&str`], without checking for
- /// valid UTF-8.
- ///
- /// # Safety
- ///
- /// The contents must be valid UTF-8.
- ///
- /// # Examples
- ///
- /// ```
- /// # use kernel::c_str;
- /// # use kernel::str::CStr;
- /// let bar = c_str!("ツ");
- /// // SAFETY: String literals are guaranteed to be valid UTF-8
- /// // by the Rust compiler.
- /// assert_eq!(unsafe { bar.as_str_unchecked() }, "ツ");
- /// ```
- #[inline]
- pub unsafe fn as_str_unchecked(&self) -> &str {
- // SAFETY: TODO.
- unsafe { core::str::from_utf8_unchecked(self.as_bytes()) }
- }
-
- /// Convert this [`CStr`] into a [`CString`] by allocating memory and
- /// copying over the string data.
- pub fn to_cstring(&self) -> Result<CString, AllocError> {
- CString::try_from(self)
- }
-
+/// Extensions to [`CStr`].
+pub trait CStrExt {
/// Converts this [`CStr`] to its ASCII lower case equivalent in-place.
///
/// ASCII letters 'A' to 'Z' are mapped to 'a' to 'z',
@@ -370,11 +216,7 @@ pub fn to_cstring(&self) -> Result<CString, AllocError> {
/// [`to_ascii_lowercase()`].
///
/// [`to_ascii_lowercase()`]: #method.to_ascii_lowercase
- pub fn make_ascii_lowercase(&mut self) {
- // INVARIANT: This doesn't introduce or remove NUL bytes in the C
- // string.
- self.0.make_ascii_lowercase();
- }
+ fn make_ascii_lowercase(&mut self);
/// Converts this [`CStr`] to its ASCII upper case equivalent in-place.
///
@@ -385,11 +227,7 @@ pub fn make_ascii_lowercase(&mut self) {
/// [`to_ascii_uppercase()`].
///
/// [`to_ascii_uppercase()`]: #method.to_ascii_uppercase
- pub fn make_ascii_uppercase(&mut self) {
- // INVARIANT: This doesn't introduce or remove NUL bytes in the C
- // string.
- self.0.make_ascii_uppercase();
- }
+ fn make_ascii_uppercase(&mut self);
/// Returns a copy of this [`CString`] where each character is mapped to its
/// ASCII lower case equivalent.
@@ -400,13 +238,7 @@ pub fn make_ascii_uppercase(&mut self) {
/// To lowercase the value in-place, use [`make_ascii_lowercase`].
///
/// [`make_ascii_lowercase`]: str::make_ascii_lowercase
- pub fn to_ascii_lowercase(&self) -> Result<CString, AllocError> {
- let mut s = self.to_cstring()?;
-
- s.make_ascii_lowercase();
-
- Ok(s)
- }
+ fn to_ascii_lowercase(&self) -> Result<CString, AllocError>;
/// Returns a copy of this [`CString`] where each character is mapped to its
/// ASCII upper case equivalent.
@@ -417,13 +249,7 @@ pub fn to_ascii_lowercase(&self) -> Result<CString, AllocError> {
/// To uppercase the value in-place, use [`make_ascii_uppercase`].
///
/// [`make_ascii_uppercase`]: str::make_ascii_uppercase
- pub fn to_ascii_uppercase(&self) -> Result<CString, AllocError> {
- let mut s = self.to_cstring()?;
-
- s.make_ascii_uppercase();
-
- Ok(s)
- }
+ fn to_ascii_uppercase(&self) -> Result<CString, AllocError>;
/// Returns an object that implements [`Display`] for safely printing a [`CStr`] that may
/// contain non-Unicode data. If you would like an implementation which escapes the [`CStr`]
@@ -440,116 +266,65 @@ pub fn to_ascii_uppercase(&self) -> Result<CString, AllocError> {
/// # use kernel::str::CString;
/// let penguin = c_str!("🐧");
/// let s = CString::try_from_fmt(fmt!("{}", penguin.display()))?;
- /// assert_eq!(s.as_bytes_with_nul(), "\\xf0\\x9f\\x90\\xa7\0".as_bytes());
+ /// assert_eq!(s.to_bytes_with_nul(), "\\xf0\\x9f\\x90\\xa7\0".as_bytes());
///
/// let ascii = c_str!("so \"cool\"");
/// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
- /// assert_eq!(s.as_bytes_with_nul(), "so \"cool\"\0".as_bytes());
+ /// assert_eq!(s.to_bytes_with_nul(), "so \"cool\"\0".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
/// ```
+ fn display(&self) -> Display<'_>;
+}
+
+/// Converts a mutable C string to a mutable byte slice.
+///
+/// # Safety
+///
+/// The caller must ensure that the slice ends in a NUL byte and contains no other NUL bytes before
+/// the borrow ends and the underlying [`CStr`] is used.
+unsafe fn to_bytes_mut(s: &mut CStr) -> &mut [u8] {
+ // SAFETY: the cast from `&CStr` to `&[u8]` is safe since `CStr` has the same layout as `&[u8]`
+ // (this is technically not guaranteed, but we rely on it here). The pointer dereference is
+ // safe since it comes from a mutable reference which is guaranteed to be valid for writes.
+ unsafe { &mut *(s as *mut CStr as *mut [u8]) }
+}
+
+impl CStrExt for CStr {
+ fn make_ascii_lowercase(&mut self) {
+ // SAFETY: This doesn't introduce or remove NUL bytes in the C string.
+ unsafe { to_bytes_mut(self) }.make_ascii_lowercase();
+ }
+
+ fn make_ascii_uppercase(&mut self) {
+ // SAFETY: This doesn't introduce or remove NUL bytes in the C string.
+ unsafe { to_bytes_mut(self) }.make_ascii_uppercase();
+ }
+
+ fn to_ascii_lowercase(&self) -> Result<CString, AllocError> {
+ let mut s = CString::try_from(self)?;
+
+ s.make_ascii_lowercase();
+
+ Ok(s)
+ }
+
+ fn to_ascii_uppercase(&self) -> Result<CString, AllocError> {
+ let mut s = CString::try_from(self)?;
+
+ s.make_ascii_uppercase();
+
+ Ok(s)
+ }
+
#[inline]
- pub fn display(&self) -> Display<'_> {
+ fn display(&self) -> Display<'_> {
Display {
- inner: self,
+ inner: BStr::from_bytes(self.to_bytes()),
escape_common: false,
}
}
}
-impl fmt::Debug for CStr {
- /// Formats printable ASCII characters with a double quote on either end, escaping the rest.
- ///
- /// ```
- /// # use kernel::c_str;
- /// # use kernel::fmt;
- /// # use kernel::str::CString;
- /// let penguin = c_str!("🐧");
- /// let s = CString::try_from_fmt(fmt!("{:?}", penguin))?;
- /// assert_eq!(s.as_bytes_with_nul(), "\"\\xf0\\x9f\\x90\\xa7\"\0".as_bytes());
- ///
- /// // Embedded double quotes are escaped.
- /// let ascii = c_str!("so \"cool\"");
- /// let s = CString::try_from_fmt(fmt!("{:?}", ascii))?;
- /// assert_eq!(s.as_bytes_with_nul(), "\"so \\\"cool\\\"\"\0".as_bytes());
- /// # Ok::<(), kernel::error::Error>(())
- /// ```
- fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
- f.write_str("\"")?;
- for &c in self.as_bytes() {
- match c {
- // Printable characters.
- b'\"' => f.write_str("\\\"")?,
- 0x20..=0x7e => f.write_char(c as char)?,
- _ => write!(f, "\\x{:02x}", c)?,
- }
- }
- f.write_str("\"")
- }
-}
-
-impl AsRef<BStr> for CStr {
- #[inline]
- fn as_ref(&self) -> &BStr {
- BStr::from_bytes(self.as_bytes())
- }
-}
-
-impl Deref for CStr {
- type Target = BStr;
-
- #[inline]
- fn deref(&self) -> &Self::Target {
- self.as_ref()
- }
-}
-
-impl Index<ops::RangeFrom<usize>> for CStr {
- type Output = CStr;
-
- #[inline]
- fn index(&self, index: ops::RangeFrom<usize>) -> &Self::Output {
- // Delegate bounds checking to slice.
- // Assign to _ to mute clippy's unnecessary operation warning.
- let _ = &self.as_bytes()[index.start..];
- // SAFETY: We just checked the bounds.
- unsafe { Self::from_bytes_with_nul_unchecked(&self.0[index.start..]) }
- }
-}
-
-impl Index<ops::RangeFull> for CStr {
- type Output = CStr;
-
- #[inline]
- fn index(&self, _index: ops::RangeFull) -> &Self::Output {
- self
- }
-}
-
-mod private {
- use core::ops;
-
- // Marker trait for index types that can be forward to `BStr`.
- pub trait CStrIndex {}
-
- impl CStrIndex for usize {}
- impl CStrIndex for ops::Range<usize> {}
- impl CStrIndex for ops::RangeInclusive<usize> {}
- impl CStrIndex for ops::RangeToInclusive<usize> {}
-}
-
-impl<Idx> Index<Idx> for CStr
-where
- Idx: private::CStrIndex,
- BStr: Index<Idx>,
-{
- type Output = <BStr as Index<Idx>>::Output;
-
- #[inline]
- fn index(&self, index: Idx) -> &Self::Output {
- &self.as_ref()[index]
- }
-}
-
/// Creates a new [`CStr`] from a string literal.
///
/// The string literal should not contain any `NUL` bytes.
@@ -630,25 +405,15 @@ fn test_cstr_to_str_panic() {
checked_cstr.to_str().unwrap();
}
- #[test]
- fn test_cstr_as_str_unchecked() {
- let good_bytes = b"\xf0\x9f\x90\xA7\0";
- let checked_cstr = CStr::from_bytes_with_nul(good_bytes).unwrap();
- // SAFETY: The contents come from a string literal which contains valid UTF-8.
- let unchecked_str = unsafe { checked_cstr.as_str_unchecked() };
- assert_eq!(unchecked_str, "🐧");
- }
-
#[test]
fn test_cstr_display() {
- let hello_world = CStr::from_bytes_with_nul(b"hello, world!\0").unwrap();
- assert_eq!(format!("{}", hello_world.display()), "hello, world!");
- let non_printables = CStr::from_bytes_with_nul(b"\x01\x09\x0a\0").unwrap();
- assert_eq!(format!("{}", non_printables.display()), "\\x01\\x09\\x0a");
- let non_ascii = CStr::from_bytes_with_nul(b"d\xe9j\xe0 vu\0").unwrap();
- assert_eq!(format!("{}", non_ascii.display()), "d\\xe9j\\xe0 vu");
- let good_bytes = CStr::from_bytes_with_nul(b"\xf0\x9f\xa6\x80\0").unwrap();
- assert_eq!(format!("{}", good_bytes.display()), "\\xf0\\x9f\\xa6\\x80");
+ assert_eq!(format!("{}", c"hello, world!".display()), "hello, world!");
+ assert_eq!(format!("{}", c"\x01\x09\x0a".display()), "\\x01\\x09\\x0a");
+ assert_eq!(format!("{}", c"d\xe9j\xe0 vu".display()), "d\\xe9j\\xe0 vu");
+ assert_eq!(
+ format!("{}", c"\xf0\x9f\xa6\x80".display()),
+ "\\xf0\\x9f\\xa6\\x80"
+ );
}
#[test]
@@ -664,14 +429,13 @@ fn test_cstr_display_all_bytes() {
#[test]
fn test_cstr_debug() {
- let hello_world = CStr::from_bytes_with_nul(b"hello, world!\0").unwrap();
- assert_eq!(format!("{:?}", hello_world), "\"hello, world!\"");
- let non_printables = CStr::from_bytes_with_nul(b"\x01\x09\x0a\0").unwrap();
- assert_eq!(format!("{:?}", non_printables), "\"\\x01\\x09\\x0a\"");
- let non_ascii = CStr::from_bytes_with_nul(b"d\xe9j\xe0 vu\0").unwrap();
- assert_eq!(format!("{:?}", non_ascii), "\"d\\xe9j\\xe0 vu\"");
- let good_bytes = CStr::from_bytes_with_nul(b"\xf0\x9f\xa6\x80\0").unwrap();
- assert_eq!(format!("{:?}", good_bytes), "\"\\xf0\\x9f\\xa6\\x80\"");
+ assert_eq!(format!("{:?}", c"hello, world!"), "\"hello, world!\"");
+ assert_eq!(format!("{:?}", c"\x01\x09\x0a"), "\"\\x01\\t\\n\"");
+ assert_eq!(format!("{:?}", c"d\xe9j\xe0 vu"), "\"d\\xe9j\\xe0 vu\"");
+ assert_eq!(
+ format!("{:?}", c"\xf0\x9f\xa6\x80"),
+ "\"\\xf0\\x9f\\xa6\\x80\""
+ );
}
#[test]
@@ -851,14 +615,14 @@ fn write_str(&mut self, s: &str) -> fmt::Result {
/// # Examples
///
/// ```
-/// use kernel::{str::CString, fmt};
+/// use kernel::{fmt, str::CString};
///
/// let s = CString::try_from_fmt(fmt!("{}{}{}", "abc", 10, 20))?;
-/// assert_eq!(s.as_bytes_with_nul(), "abc1020\0".as_bytes());
+/// assert_eq!(s.to_bytes_with_nul(), "abc1020\0".as_bytes());
///
/// let tmp = "testing";
/// let s = CString::try_from_fmt(fmt!("{tmp}{}", 123))?;
-/// assert_eq!(s.as_bytes_with_nul(), "testing123\0".as_bytes());
+/// assert_eq!(s.to_bytes_with_nul(), "testing123\0".as_bytes());
///
/// // This fails because it has an embedded `NUL` byte.
/// let s = CString::try_from_fmt(fmt!("a\0b{}", 123));
@@ -916,9 +680,11 @@ fn deref(&self) -> &Self::Target {
impl DerefMut for CString {
fn deref_mut(&mut self) -> &mut Self::Target {
- // SAFETY: A `CString` is always NUL-terminated and contains no other
- // NUL bytes.
- unsafe { CStr::from_bytes_with_nul_unchecked_mut(self.buf.as_mut_slice()) }
+ // SAFETY: the cast from `&[u8]` to `&CStr` is safe since `CStr` has the same layout as
+ // `&[u8]` (this is technically not guaranteed, but we rely on it here). The pointer
+ // dereference is safe since it comes from a mutable reference which is guaranteed to be
+ // valid for writes.
+ unsafe { &mut *(self.buf.as_mut_slice() as *mut [u8] as *mut CStr) }
}
}
@@ -928,7 +694,7 @@ impl<'a> TryFrom<&'a CStr> for CString {
fn try_from(cstr: &'a CStr) -> Result<CString, AllocError> {
let mut buf = KVec::new();
- buf.extend_from_slice(cstr.as_bytes_with_nul(), GFP_KERNEL)?;
+ buf.extend_from_slice(cstr.to_bytes_with_nul(), GFP_KERNEL)?;
// INVARIANT: The `CStr` and `CString` types have the same invariants for
// the string data, and we copied it over without changes.
diff --git a/rust/kernel/sync/condvar.rs b/rust/kernel/sync/condvar.rs
index 7df565038d7d..7bf3df980433 100644
--- a/rust/kernel/sync/condvar.rs
+++ b/rust/kernel/sync/condvar.rs
@@ -107,7 +107,7 @@ pub fn new(name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self
// SAFETY: `slot` is valid while the closure is called and both `name` and `key` have
// static lifetimes so they live indefinitely.
wait_queue_head <- Opaque::ffi_init(|slot| unsafe {
- bindings::__init_waitqueue_head(slot, name.as_char_ptr(), key.as_ptr())
+ bindings::__init_waitqueue_head(slot, crate::str::as_char_ptr(name), key.as_ptr())
}),
})
}
diff --git a/rust/kernel/sync/lock.rs b/rust/kernel/sync/lock.rs
index eb80048e0110..5ad62d718279 100644
--- a/rust/kernel/sync/lock.rs
+++ b/rust/kernel/sync/lock.rs
@@ -136,7 +136,7 @@ pub fn new(t: T, name: &'static CStr, key: &'static LockClassKey) -> impl PinIni
// SAFETY: `slot` is valid while the closure is called and both `name` and `key` have
// static lifetimes so they live indefinitely.
state <- Opaque::ffi_init(|slot| unsafe {
- B::init(slot, name.as_char_ptr(), key.as_ptr())
+ B::init(slot, crate::str::as_char_ptr(name), key.as_ptr())
}),
})
}
diff --git a/rust/kernel/sync/lock/global.rs b/rust/kernel/sync/lock/global.rs
index 480ee724e3cc..4c4d60a51c1f 100644
--- a/rust/kernel/sync/lock/global.rs
+++ b/rust/kernel/sync/lock/global.rs
@@ -69,7 +69,7 @@ pub unsafe fn init(&'static self) {
unsafe {
B::Backend::init(
self.inner.state.get(),
- B::NAME.as_char_ptr(),
+ crate::str::as_char_ptr(B::NAME),
B::get_lock_class().as_ptr(),
)
}
diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index 0cd100d2aefb..1008dd2635e1 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -382,7 +382,7 @@ pub fn new(name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self
slot,
Some(T::Pointer::run),
false,
- name.as_char_ptr(),
+ crate::str::as_char_ptr(name),
key.as_ptr(),
)
}
--
2.48.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v7 3/4] rust: replace `kernel::c_str!` with C-Strings
2025-02-02 16:31 [PATCH v7 0/4] rust: replace kernel::str::CStr w/ core::ffi::CStr Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 1/4] rust: move BStr,CStr Display impls behind method Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 2/4] rust: replace `CStr` with `core::ffi::CStr` Tamir Duberstein
@ 2025-02-02 16:31 ` Tamir Duberstein
2025-02-02 16:31 ` [PATCH v7 4/4] rust: remove core::ffi::CStr reexport Tamir Duberstein
3 siblings, 0 replies; 5+ messages in thread
From: Tamir Duberstein @ 2025-02-02 16:31 UTC (permalink / raw)
To: Michal Rostecki, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Benno Lossin, Andreas Hindborg, Alice Ryhl,
Trevor Gross
Cc: rust-for-linux, linux-kernel, Tamir Duberstein
C-String literals were added in Rust 1.77. Replace instances of
`kernel::c_str!` with C-String literals where possible and rename
`kernel::c_str!` to `c_str_avoid_literals` to clarify its intended use.
Closes: https://github.com/Rust-for-Linux/linux/issues/1075
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
drivers/net/phy/ax88796b_rust.rs | 7 +++----
drivers/net/phy/qt2025.rs | 5 ++---
rust/kernel/devres.rs | 2 +-
rust/kernel/firmware.rs | 4 ++--
rust/kernel/kunit.rs | 7 ++++---
rust/kernel/net/phy.rs | 6 ++----
rust/kernel/platform.rs | 4 ++--
rust/kernel/str.rs | 37 +++++++++++++++++++++++-------------
rust/kernel/sync.rs | 4 ++--
rust/kernel/sync/lock/global.rs | 3 ++-
rust/macros/module.rs | 2 +-
samples/rust/rust_driver_pci.rs | 4 ++--
samples/rust/rust_driver_platform.rs | 4 ++--
samples/rust/rust_misc_device.rs | 3 +--
14 files changed, 50 insertions(+), 42 deletions(-)
diff --git a/drivers/net/phy/ax88796b_rust.rs b/drivers/net/phy/ax88796b_rust.rs
index 8c7eb009d9fc..b07d36f45a43 100644
--- a/drivers/net/phy/ax88796b_rust.rs
+++ b/drivers/net/phy/ax88796b_rust.rs
@@ -5,7 +5,6 @@
//!
//! C version of this driver: [`drivers/net/phy/ax88796b.c`](./ax88796b.c)
use kernel::{
- c_str,
net::phy::{self, reg::C22, DeviceId, Driver},
prelude::*,
uapi,
@@ -41,7 +40,7 @@ fn asix_soft_reset(dev: &mut phy::Device) -> Result {
#[vtable]
impl Driver for PhyAX88772A {
const FLAGS: u32 = phy::flags::IS_INTERNAL;
- const NAME: &'static CStr = c_str!("Asix Electronics AX88772A");
+ const NAME: &'static CStr = c"Asix Electronics AX88772A";
const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_exact_mask(0x003b1861);
// AX88772A is not working properly with some old switches (NETGEAR EN 108TP):
@@ -105,7 +104,7 @@ fn link_change_notify(dev: &mut phy::Device) {
#[vtable]
impl Driver for PhyAX88772C {
const FLAGS: u32 = phy::flags::IS_INTERNAL;
- const NAME: &'static CStr = c_str!("Asix Electronics AX88772C");
+ const NAME: &'static CStr = c"Asix Electronics AX88772C";
const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_exact_mask(0x003b1881);
fn suspend(dev: &mut phy::Device) -> Result {
@@ -125,7 +124,7 @@ fn soft_reset(dev: &mut phy::Device) -> Result {
#[vtable]
impl Driver for PhyAX88796B {
- const NAME: &'static CStr = c_str!("Asix Electronics AX88796B");
+ const NAME: &'static CStr = c"Asix Electronics AX88796B";
const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_model_mask(0x003b1841);
fn soft_reset(dev: &mut phy::Device) -> Result {
diff --git a/drivers/net/phy/qt2025.rs b/drivers/net/phy/qt2025.rs
index 1ab065798175..2f4ba85a0d73 100644
--- a/drivers/net/phy/qt2025.rs
+++ b/drivers/net/phy/qt2025.rs
@@ -9,7 +9,6 @@
//!
//! The QT2025 PHY integrates an Intel 8051 micro-controller.
-use kernel::c_str;
use kernel::error::code;
use kernel::firmware::Firmware;
use kernel::net::phy::{
@@ -36,7 +35,7 @@
#[vtable]
impl Driver for PhyQT2025 {
- const NAME: &'static CStr = c_str!("QT2025 10Gpbs SFP+");
+ const NAME: &'static CStr = c"QT2025 10Gpbs SFP+";
const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x0043a400);
fn probe(dev: &mut phy::Device) -> Result<()> {
@@ -69,7 +68,7 @@ fn probe(dev: &mut phy::Device) -> Result<()> {
// The micro-controller will start running from the boot ROM.
dev.write(C45::new(Mmd::PCS, 0xe854), 0x00c0)?;
- let fw = Firmware::request(c_str!("qt2025-2.0.3.3.fw"), dev.as_ref())?;
+ let fw = Firmware::request(c"qt2025-2.0.3.3.fw", dev.as_ref())?;
if fw.data().len() > SZ_16K + SZ_8K {
return Err(code::EFBIG);
}
diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs
index 942376f6f3af..68af33ca2f25 100644
--- a/rust/kernel/devres.rs
+++ b/rust/kernel/devres.rs
@@ -45,7 +45,7 @@ struct DevresInner<T> {
/// # Example
///
/// ```no_run
-/// # use kernel::{bindings, c_str, device::Device, devres::Devres, io::{Io, IoRaw}};
+/// # use kernel::{bindings, device::Device, devres::Devres, io::{Io, IoRaw}};
/// # use core::ops::Deref;
///
/// // See also [`pci::Bar`] for a real example.
diff --git a/rust/kernel/firmware.rs b/rust/kernel/firmware.rs
index e75db4d825ce..93e375e75ca0 100644
--- a/rust/kernel/firmware.rs
+++ b/rust/kernel/firmware.rs
@@ -40,13 +40,13 @@ fn request_nowarn() -> Self {
/// # Examples
///
/// ```no_run
-/// # use kernel::{c_str, device::Device, firmware::Firmware};
+/// # use kernel::{device::Device, firmware::Firmware};
///
/// # fn no_run() -> Result<(), Error> {
/// # // SAFETY: *NOT* safe, just for the example to get an `ARef<Device>` instance
/// # let dev = unsafe { Device::get_device(core::ptr::null_mut()) };
///
-/// let fw = Firmware::request(c_str!("path/to/firmware.bin"), &dev)?;
+/// let fw = Firmware::request(c"path/to/firmware.bin", &dev)?;
/// let blob = fw.data();
///
/// # Ok(())
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 9f40ea744fc2..3d812edec057 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -56,10 +56,11 @@ macro_rules! kunit_assert {
break 'out;
}
- static NAME: &'static $crate::str::CStr = $crate::c_str!($name);
- static FILE: &'static $crate::str::CStr = $crate::c_str!($file);
+ static NAME: &'static $crate::str::CStr = $crate::c_str_avoid_literals!($name);
+ static FILE: &'static $crate::str::CStr = $crate::c_str_avoid_literals!($file);
static LINE: i32 = core::line!() as i32 - $diff;
- static CONDITION: &'static $crate::str::CStr = $crate::c_str!(stringify!($condition));
+ static CONDITION: &'static $crate::str::CStr =
+ $crate::c_str_avoid_literals!(stringify!($condition));
// SAFETY: FFI call without safety requirements.
let kunit_test = unsafe { $crate::bindings::kunit_get_current_test() };
diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs
index c60205606aee..631a81e79a9f 100644
--- a/rust/kernel/net/phy.rs
+++ b/rust/kernel/net/phy.rs
@@ -780,7 +780,6 @@ const fn as_int(&self) -> u32 {
///
/// ```
/// # mod module_phy_driver_sample {
-/// use kernel::c_str;
/// use kernel::net::phy::{self, DeviceId};
/// use kernel::prelude::*;
///
@@ -799,7 +798,7 @@ const fn as_int(&self) -> u32 {
///
/// #[vtable]
/// impl phy::Driver for PhySample {
-/// const NAME: &'static CStr = c_str!("PhySample");
+/// const NAME: &'static CStr = c"PhySample";
/// const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x00000001);
/// }
/// # }
@@ -808,7 +807,6 @@ const fn as_int(&self) -> u32 {
/// This expands to the following code:
///
/// ```ignore
-/// use kernel::c_str;
/// use kernel::net::phy::{self, DeviceId};
/// use kernel::prelude::*;
///
@@ -828,7 +826,7 @@ const fn as_int(&self) -> u32 {
///
/// #[vtable]
/// impl phy::Driver for PhySample {
-/// const NAME: &'static CStr = c_str!("PhySample");
+/// const NAME: &'static CStr = c"PhySample";
/// const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x00000001);
/// }
///
diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index d1752a978af4..f23a433b2273 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -120,7 +120,7 @@ macro_rules! module_platform_driver {
/// # Example
///
///```
-/// # use kernel::{bindings, c_str, of, platform};
+/// # use kernel::{bindings, of, platform};
///
/// struct MyDriver;
///
@@ -129,7 +129,7 @@ macro_rules! module_platform_driver {
/// MODULE_OF_TABLE,
/// <MyDriver as platform::Driver>::IdInfo,
/// [
-/// (of::DeviceId::new(c_str!("test,device")), ())
+/// (of::DeviceId::new(c"test,device"), ())
/// ]
/// );
///
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 0c4189a478b4..27911eaede27 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -261,14 +261,13 @@ pub trait CStrExt {
/// # Examples
///
/// ```
- /// # use kernel::c_str;
/// # use kernel::fmt;
/// # use kernel::str::CString;
- /// let penguin = c_str!("🐧");
+ /// let penguin = c"🐧";
/// let s = CString::try_from_fmt(fmt!("{}", penguin.display()))?;
/// assert_eq!(s.to_bytes_with_nul(), "\\xf0\\x9f\\x90\\xa7\0".as_bytes());
///
- /// let ascii = c_str!("so \"cool\"");
+ /// let ascii = c"so \"cool\"";
/// let s = CString::try_from_fmt(fmt!("{}", ascii.display()))?;
/// assert_eq!(s.to_bytes_with_nul(), "so \"cool\"\0".as_bytes());
/// # Ok::<(), kernel::error::Error>(())
@@ -325,25 +324,37 @@ fn display(&self) -> Display<'_> {
}
}
-/// Creates a new [`CStr`] from a string literal.
+/// Creates a static C string wrapper at compile time.
///
-/// The string literal should not contain any `NUL` bytes.
+/// Rust supports C string literals since Rust 1.77, and they should be used instead of this macro
+/// where possible. This macro exists to allow static *non-literal* C strings to be created at
+/// compile time. This is most often used in other macros.
+///
+/// # Panics
+///
+/// This macro panics if the operand contains an interior `NUL` byte.
///
/// # Examples
///
/// ```
-/// # use kernel::c_str;
+/// # use kernel::c_str_avoid_literals;
/// # use kernel::str::CStr;
-/// const MY_CSTR: &CStr = c_str!("My awesome CStr!");
+/// const MY_CSTR: &CStr = c_str_avoid_literals!(concat!(file!(), ":", line!(), ": My CStr!"));
/// ```
#[macro_export]
-macro_rules! c_str {
+macro_rules! c_str_avoid_literals {
+ // NB: we could write `($str:lit) => compile_error!("use a C string literal instead");` here but
+ // that would trigger when the literal is at the top of several macro expansions. That would be
+ // too limiting to macro authors, so we rely on the name as a hint instead.
($str:expr) => {{
- const S: &str = concat!($str, "\0");
- const C: &$crate::str::CStr = match $crate::str::CStr::from_bytes_with_nul(S.as_bytes()) {
- Ok(v) => v,
- Err(_) => panic!("string contains interior NUL"),
- };
+ const S: &'static str = concat!($str, "\0");
+ const C: &'static $crate::str::CStr =
+ match $crate::str::CStr::from_bytes_with_nul(S.as_bytes()) {
+ Ok(v) => v,
+ Err(core::ffi::FromBytesWithNulError { .. }) => {
+ panic!("string contains interior NUL")
+ }
+ };
C
}};
}
diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
index 3498fb344dc9..f86d109b4b89 100644
--- a/rust/kernel/sync.rs
+++ b/rust/kernel/sync.rs
@@ -62,9 +62,9 @@ macro_rules! static_lock_class {
#[macro_export]
macro_rules! optional_name {
() => {
- $crate::c_str!(::core::concat!(::core::file!(), ":", ::core::line!()))
+ $crate::c_str_avoid_literals!(::core::concat!(::core::file!(), ":", ::core::line!()))
};
($name:literal) => {
- $crate::c_str!($name)
+ $crate::c_str_avoid_literals!($name)
};
}
diff --git a/rust/kernel/sync/lock/global.rs b/rust/kernel/sync/lock/global.rs
index 4c4d60a51c1f..732dde45024b 100644
--- a/rust/kernel/sync/lock/global.rs
+++ b/rust/kernel/sync/lock/global.rs
@@ -266,7 +266,8 @@ macro_rules! global_lock {
$pub enum $name {}
impl $crate::sync::lock::GlobalLockBackend for $name {
- const NAME: &'static $crate::str::CStr = $crate::c_str!(::core::stringify!($name));
+ const NAME: &'static $crate::str::CStr =
+ $crate::c_str_avoid_literals!(::core::stringify!($name));
type Item = $valuety;
type Backend = $crate::global_lock_inner!(backend $kind);
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index cdf94f4982df..a534fabd29d6 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -229,7 +229,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
}};
impl kernel::ModuleMetadata for {type_} {{
- const NAME: &'static kernel::str::CStr = kernel::c_str!(\"{name}\");
+ const NAME: &'static kernel::str::CStr = c\"{name}\";
}}
// Double nested modules, since then nobody can access the public items inside.
diff --git a/samples/rust/rust_driver_pci.rs b/samples/rust/rust_driver_pci.rs
index 1fb6e44f3395..cb4a9247ff5e 100644
--- a/samples/rust/rust_driver_pci.rs
+++ b/samples/rust/rust_driver_pci.rs
@@ -4,7 +4,7 @@
//!
//! To make this driver probe, QEMU must be run with `-device pci-testdev`.
-use kernel::{bindings, c_str, devres::Devres, pci, prelude::*};
+use kernel::{bindings, devres::Devres, pci, prelude::*};
struct Regs;
@@ -73,7 +73,7 @@ fn probe(pdev: &mut pci::Device, info: &Self::IdInfo) -> Result<Pin<KBox<Self>>>
pdev.enable_device_mem()?;
pdev.set_master();
- let bar = pdev.iomap_region_sized::<{ Regs::END }>(0, c_str!("rust_driver_pci"))?;
+ let bar = pdev.iomap_region_sized::<{ Regs::END }>(0, c"rust_driver_pci")?;
let drvdata = KBox::new(
Self {
diff --git a/samples/rust/rust_driver_platform.rs b/samples/rust/rust_driver_platform.rs
index 8120609e2940..d2df2d0f8261 100644
--- a/samples/rust/rust_driver_platform.rs
+++ b/samples/rust/rust_driver_platform.rs
@@ -2,7 +2,7 @@
//! Rust Platform driver sample.
-use kernel::{c_str, of, platform, prelude::*};
+use kernel::{of, platform, prelude::*};
struct SampleDriver {
pdev: platform::Device,
@@ -14,7 +14,7 @@ struct SampleDriver {
OF_TABLE,
MODULE_OF_TABLE,
<SampleDriver as platform::Driver>::IdInfo,
- [(of::DeviceId::new(c_str!("test,rust-device")), Info(42))]
+ [(of::DeviceId::new(c"test,rust-device"), Info(42))]
);
impl platform::Driver for SampleDriver {
diff --git a/samples/rust/rust_misc_device.rs b/samples/rust/rust_misc_device.rs
index 40ad7266c225..9d85819a195b 100644
--- a/samples/rust/rust_misc_device.rs
+++ b/samples/rust/rust_misc_device.rs
@@ -97,7 +97,6 @@
use core::pin::Pin;
use kernel::{
- c_str,
device::Device,
fs::File,
ioctl::{_IO, _IOC_SIZE, _IOR, _IOW},
@@ -132,7 +131,7 @@ fn init(_module: &'static ThisModule) -> impl PinInit<Self, Error> {
pr_info!("Initialising Rust Misc Device Sample\n");
let options = MiscDeviceOptions {
- name: c_str!("rust-misc-device"),
+ name: c"rust-misc-device",
};
try_pin_init!(Self {
--
2.48.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v7 4/4] rust: remove core::ffi::CStr reexport
2025-02-02 16:31 [PATCH v7 0/4] rust: replace kernel::str::CStr w/ core::ffi::CStr Tamir Duberstein
` (2 preceding siblings ...)
2025-02-02 16:31 ` [PATCH v7 3/4] rust: replace `kernel::c_str!` with C-Strings Tamir Duberstein
@ 2025-02-02 16:31 ` Tamir Duberstein
3 siblings, 0 replies; 5+ messages in thread
From: Tamir Duberstein @ 2025-02-02 16:31 UTC (permalink / raw)
To: Michal Rostecki, Miguel Ojeda, Alex Gaynor, Boqun Feng, Gary Guo,
Björn Roy Baron, Benno Lossin, Andreas Hindborg, Alice Ryhl,
Trevor Gross
Cc: rust-for-linux, linux-kernel, Tamir Duberstein
Clean up references to `kernel::str::CStr`.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
rust/kernel/device.rs | 3 +--
rust/kernel/driver.rs | 4 ++--
rust/kernel/error.rs | 6 ++----
rust/kernel/firmware.rs | 3 ++-
rust/kernel/kunit.rs | 6 +++---
rust/kernel/lib.rs | 2 +-
rust/kernel/miscdevice.rs | 3 +--
rust/kernel/of.rs | 4 ++--
rust/kernel/pci.rs | 3 +--
rust/kernel/platform.rs | 3 +--
rust/kernel/prelude.rs | 5 +----
rust/kernel/str.rs | 19 +++++++++----------
rust/kernel/sync/condvar.rs | 2 +-
rust/kernel/sync/lock.rs | 3 +--
rust/kernel/sync/lock/global.rs | 4 ++--
rust/kernel/sync/poll.rs | 1 +
rust/kernel/workqueue.rs | 1 +
rust/macros/module.rs | 2 +-
18 files changed, 33 insertions(+), 41 deletions(-)
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index 9554921368c0..7248bfcfe8f2 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -6,10 +6,9 @@
use crate::{
bindings,
- str::CStr,
types::{ARef, Opaque},
};
-use core::{fmt, ptr};
+use core::{ffi::CStr, fmt, ptr};
/// A reference-counted device.
///
diff --git a/rust/kernel/driver.rs b/rust/kernel/driver.rs
index 2a16d5e64e6c..0fbcdc226729 100644
--- a/rust/kernel/driver.rs
+++ b/rust/kernel/driver.rs
@@ -6,8 +6,8 @@
//! register using the [`Registration`] class.
use crate::error::{Error, Result};
-use crate::{device, init::PinInit, of, str::CStr, try_pin_init, types::Opaque, ThisModule};
-use core::pin::Pin;
+use crate::{device, init::PinInit, of, try_pin_init, types::Opaque, ThisModule};
+use core::{ffi::CStr, pin::Pin};
use macros::{pin_data, pinned_drop};
/// The [`RegistrationOps`] trait serves as generic interface for subsystems (e.g., PCI, Platform,
diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs
index 51c5e0f0a0bc..81972a8f695d 100644
--- a/rust/kernel/error.rs
+++ b/rust/kernel/error.rs
@@ -4,11 +4,9 @@
//!
//! C header: [`include/uapi/asm-generic/errno-base.h`](srctree/include/uapi/asm-generic/errno-base.h)
-use crate::{
- alloc::{layout::LayoutError, AllocError},
- str::CStr,
-};
+use crate::alloc::{layout::LayoutError, AllocError};
+use core::ffi::CStr;
use core::fmt;
use core::num::NonZeroI32;
use core::num::TryFromIntError;
diff --git a/rust/kernel/firmware.rs b/rust/kernel/firmware.rs
index 93e375e75ca0..86ed79cef211 100644
--- a/rust/kernel/firmware.rs
+++ b/rust/kernel/firmware.rs
@@ -4,7 +4,8 @@
//!
//! C header: [`include/linux/firmware.h`](srctree/include/linux/firmware.h)
-use crate::{bindings, device::Device, error::Error, error::Result, str::CStr};
+use crate::{bindings, device::Device, error::Error, error::Result};
+use core::ffi::CStr;
use core::ptr::NonNull;
/// # Invariants
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 3d812edec057..f83988959257 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -56,10 +56,10 @@ macro_rules! kunit_assert {
break 'out;
}
- static NAME: &'static $crate::str::CStr = $crate::c_str_avoid_literals!($name);
- static FILE: &'static $crate::str::CStr = $crate::c_str_avoid_literals!($file);
+ static NAME: &'static core::ffi::CStr = $crate::c_str_avoid_literals!($name);
+ static FILE: &'static core::ffi::CStr = $crate::c_str_avoid_literals!($file);
static LINE: i32 = core::line!() as i32 - $diff;
- static CONDITION: &'static $crate::str::CStr =
+ static CONDITION: &'static core::ffi::CStr =
$crate::c_str_avoid_literals!(stringify!($condition));
// SAFETY: FFI call without safety requirements.
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 496ed32b0911..a129ef3292dc 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -132,7 +132,7 @@ fn init(module: &'static ThisModule) -> impl init::PinInit<Self, error::Error> {
/// Metadata attached to a [`Module`] or [`InPlaceModule`].
pub trait ModuleMetadata {
/// The name of the module as specified in the `module!` macro.
- const NAME: &'static crate::str::CStr;
+ const NAME: &'static core::ffi::CStr;
}
/// Equivalent to `THIS_MODULE` in the C API.
diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
index 65f70ff61eb3..e8c272e24bd0 100644
--- a/rust/kernel/miscdevice.rs
+++ b/rust/kernel/miscdevice.rs
@@ -16,10 +16,9 @@
fs::File,
prelude::*,
seq_file::SeqFile,
- str::CStr,
types::{ForeignOwnable, Opaque},
};
-use core::{marker::PhantomData, mem::MaybeUninit, pin::Pin};
+use core::{ffi::CStr, marker::PhantomData, mem::MaybeUninit, pin::Pin};
/// Options for creating a misc device.
#[derive(Copy, Clone)]
diff --git a/rust/kernel/of.rs b/rust/kernel/of.rs
index 12ea65df46de..04d8dc924147 100644
--- a/rust/kernel/of.rs
+++ b/rust/kernel/of.rs
@@ -2,7 +2,7 @@
//! Device Tree / Open Firmware abstractions.
-use crate::{bindings, device_id::RawDeviceId, prelude::*};
+use crate::{bindings, device_id::RawDeviceId};
/// IdTable type for OF drivers.
pub type IdTable<T> = &'static dyn kernel::device_id::IdTable<DeviceId, T>;
@@ -28,7 +28,7 @@ fn index(&self) -> usize {
impl DeviceId {
/// Create a new device id from an OF 'compatible' string.
- pub const fn new(compatible: &'static CStr) -> Self {
+ pub const fn new(compatible: &'static core::ffi::CStr) -> Self {
let src = compatible.to_bytes_with_nul();
// Replace with `bindings::of_device_id::default()` once stabilized for `const`.
// SAFETY: FFI type is valid to be zero-initialized.
diff --git a/rust/kernel/pci.rs b/rust/kernel/pci.rs
index af36ddac80ff..d248b966cab4 100644
--- a/rust/kernel/pci.rs
+++ b/rust/kernel/pci.rs
@@ -13,11 +13,10 @@
error::{to_result, Result},
io::Io,
io::IoRaw,
- str::CStr,
types::{ARef, ForeignOwnable, Opaque},
ThisModule,
};
-use core::{ops::Deref, ptr::addr_of_mut};
+use core::{ffi::CStr, ops::Deref, ptr::addr_of_mut};
use kernel::prelude::*;
/// An adapter for the registration of PCI drivers.
diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index f23a433b2273..b8aabc229442 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -9,12 +9,11 @@
error::{to_result, Result},
of,
prelude::*,
- str::CStr,
types::{ARef, ForeignOwnable, Opaque},
ThisModule,
};
-use core::ptr::addr_of_mut;
+use core::{ffi::CStr, ptr::addr_of_mut};
/// An adapter for the registration of platform drivers.
pub struct Adapter<T: Driver>(T);
diff --git a/rust/kernel/prelude.rs b/rust/kernel/prelude.rs
index 96e7029c27da..21fa7b3a68c3 100644
--- a/rust/kernel/prelude.rs
+++ b/rust/kernel/prelude.rs
@@ -34,10 +34,7 @@
pub use super::error::{code::*, Error, Result};
-pub use super::{
- str::{CStr, CStrExt as _},
- ThisModule,
-};
+pub use super::{str::CStrExt as _, ThisModule};
pub use super::init::{InPlaceInit, InPlaceWrite, Init, PinInit};
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 27911eaede27..a68acb54f0c8 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -3,6 +3,7 @@
//! String representations.
use crate::alloc::{flags::*, AllocError, KVec};
+use core::ffi::CStr;
use core::fmt::{self, Write};
use core::ops::{Deref, DerefMut};
@@ -177,8 +178,6 @@ macro_rules! b_str {
}};
}
-pub use core::ffi::CStr;
-
/// Wraps a raw C string with a safe C string wrapper.
///
/// # Safety
@@ -338,7 +337,7 @@ fn display(&self) -> Display<'_> {
///
/// ```
/// # use kernel::c_str_avoid_literals;
-/// # use kernel::str::CStr;
+/// # use core::ffi::CStr;
/// const MY_CSTR: &CStr = c_str_avoid_literals!(concat!(file!(), ":", line!(), ": My CStr!"));
/// ```
#[macro_export]
@@ -348,13 +347,13 @@ macro_rules! c_str_avoid_literals {
// too limiting to macro authors, so we rely on the name as a hint instead.
($str:expr) => {{
const S: &'static str = concat!($str, "\0");
- const C: &'static $crate::str::CStr =
- match $crate::str::CStr::from_bytes_with_nul(S.as_bytes()) {
- Ok(v) => v,
- Err(core::ffi::FromBytesWithNulError { .. }) => {
- panic!("string contains interior NUL")
- }
- };
+ const C: &'static core::ffi::CStr = match core::ffi::CStr::from_bytes_with_nul(S.as_bytes())
+ {
+ Ok(v) => v,
+ Err(core::ffi::FromBytesWithNulError { .. }) => {
+ panic!("string contains interior NUL")
+ }
+ };
C
}};
}
diff --git a/rust/kernel/sync/condvar.rs b/rust/kernel/sync/condvar.rs
index 7bf3df980433..3b82acdcd56c 100644
--- a/rust/kernel/sync/condvar.rs
+++ b/rust/kernel/sync/condvar.rs
@@ -10,11 +10,11 @@
ffi::{c_int, c_long},
init::PinInit,
pin_init,
- str::CStr,
task::{MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE, TASK_NORMAL, TASK_UNINTERRUPTIBLE},
time::Jiffies,
types::Opaque,
};
+use core::ffi::CStr;
use core::marker::PhantomPinned;
use core::ptr;
use macros::pin_data;
diff --git a/rust/kernel/sync/lock.rs b/rust/kernel/sync/lock.rs
index 5ad62d718279..7951c0ca60cb 100644
--- a/rust/kernel/sync/lock.rs
+++ b/rust/kernel/sync/lock.rs
@@ -9,10 +9,9 @@
use crate::{
init::PinInit,
pin_init,
- str::CStr,
types::{NotThreadSafe, Opaque, ScopeGuard},
};
-use core::{cell::UnsafeCell, marker::PhantomPinned};
+use core::{cell::UnsafeCell, ffi::CStr, marker::PhantomPinned};
use macros::pin_data;
pub mod mutex;
diff --git a/rust/kernel/sync/lock/global.rs b/rust/kernel/sync/lock/global.rs
index 732dde45024b..ee438654eb6c 100644
--- a/rust/kernel/sync/lock/global.rs
+++ b/rust/kernel/sync/lock/global.rs
@@ -5,13 +5,13 @@
//! Support for defining statics containing locks.
use crate::{
- str::CStr,
sync::lock::{Backend, Guard, Lock},
sync::{LockClassKey, LockedBy},
types::Opaque,
};
use core::{
cell::UnsafeCell,
+ ffi::CStr,
marker::{PhantomData, PhantomPinned},
};
@@ -266,7 +266,7 @@ macro_rules! global_lock {
$pub enum $name {}
impl $crate::sync::lock::GlobalLockBackend for $name {
- const NAME: &'static $crate::str::CStr =
+ const NAME: &'static core::ffi::CStr =
$crate::c_str_avoid_literals!(::core::stringify!($name));
type Item = $valuety;
type Backend = $crate::global_lock_inner!(backend $kind);
diff --git a/rust/kernel/sync/poll.rs b/rust/kernel/sync/poll.rs
index d5f17153b424..3349f48725f2 100644
--- a/rust/kernel/sync/poll.rs
+++ b/rust/kernel/sync/poll.rs
@@ -11,6 +11,7 @@
sync::{CondVar, LockClassKey},
types::Opaque,
};
+use core::ffi::CStr;
use core::ops::Deref;
/// Creates a [`PollCondVar`] initialiser with the given name and a newly-created lock class.
diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index 1008dd2635e1..69f419bdb0e7 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -135,6 +135,7 @@
use crate::alloc::{AllocError, Flags};
use crate::{prelude::*, sync::Arc, sync::LockClassKey, types::Opaque};
+use core::ffi::CStr;
use core::marker::PhantomData;
/// Creates a [`Work`] initialiser with the given name and a newly-created lock class.
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index a534fabd29d6..7f81cbbcc4ef 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -229,7 +229,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
}};
impl kernel::ModuleMetadata for {type_} {{
- const NAME: &'static kernel::str::CStr = c\"{name}\";
+ const NAME: &'static core::ffi::CStr = c\"{name}\";
}}
// Double nested modules, since then nobody can access the public items inside.
--
2.48.1
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