diff mbox series

[v2] rust: str: add {make,to}_{upper,lower}case() to CString

Message ID 20240130023843.11512-1-dakr@redhat.com
State New
Headers
Series [v2] rust: str: add {make,to}_{upper,lower}case() to CString |

Commit Message

Danilo Krummrich Jan. 30, 2024, 2:35 a.m. UTC 
  Add functions to convert a CString to upper- / lowercase, either
in-place or by creating a copy of the original CString.

Naming followes the one from the Rust stdlib, where functions starting
with 'to' create a copy and functions starting with 'make' perform an
in-place conversion.

This is required by the Nova project (GSP only Rust successor of
Nouveau) to convert stringified enum values (representing different GPU
chipsets) to strings in order to generate the corresponding firmware
paths. See also [1].

[1] https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/String.20manipulation.20in.20kernel.20Rust

Signed-off-by: Danilo Krummrich <dakr@redhat.com>
---
Changes in V2:
  - expand commit message mentioning the use case
  - expand function doc comments to match the ones from Rust's stdlib
  - rename to_* to make_* and add the actual to_* implementations
---
 rust/kernel/str.rs | 60 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)


base-commit: 41bccc98fb7931d63d03f326a746ac4d429c1dd3

Comments

Danilo Krummrich Feb. 13, 2024, 2:12 p.m. UTC | #1 
On 1/30/24 03:35, Danilo Krummrich wrote:
> Add functions to convert a CString to upper- / lowercase, either
> in-place or by creating a copy of the original CString.
> 
> Naming followes the one from the Rust stdlib, where functions starting
> with 'to' create a copy and functions starting with 'make' perform an
> in-place conversion.
> 
> This is required by the Nova project (GSP only Rust successor of
> Nouveau) to convert stringified enum values (representing different GPU
> chipsets) to strings in order to generate the corresponding firmware
> paths. See also [1].
> 
> [1] https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/String.20manipulation.20in.20kernel.20Rust
> 
> Signed-off-by: Danilo Krummrich <dakr@redhat.com>

Ping.

> ---
> Changes in V2:
>    - expand commit message mentioning the use case
>    - expand function doc comments to match the ones from Rust's stdlib
>    - rename to_* to make_* and add the actual to_* implementations
> ---
>   rust/kernel/str.rs | 60 ++++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 60 insertions(+)
> 
> diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
> index 7d848b83add4..758bb70d98e9 100644
> --- a/rust/kernel/str.rs
> +++ b/rust/kernel/str.rs
> @@ -581,6 +581,66 @@ pub fn try_from_fmt(args: fmt::Arguments<'_>) -> Result<Self, Error> {
>           // exist in the buffer.
>           Ok(Self { buf })
>       }
> +
> +    /// Converts this CString to its ASCII lower case equivalent in-place.
> +    ///
> +    /// ASCII letters 'A' to 'Z' are mapped to 'a' to 'z',
> +    /// but non-ASCII letters are unchanged.
> +    ///
> +    /// To return a new lowercased value without modifying the existing one, use
> +    /// [`to_ascii_lowercase()`].
> +    ///
> +    /// [`to_ascii_lowercase()`]: #method.to_ascii_lowercase
> +    pub fn make_ascii_lowercase(&mut self) {
> +        self.buf.make_ascii_lowercase();
> +    }
> +
> +    /// Converts this CString to its ASCII upper case equivalent in-place.
> +    ///
> +    /// ASCII letters 'a' to 'z' are mapped to 'A' to 'Z',
> +    /// but non-ASCII letters are unchanged.
> +    ///
> +    /// To return a new uppercased value without modifying the existing one, use
> +    /// [`to_ascii_uppercase()`].
> +    ///
> +    /// [`to_ascii_uppercase()`]: #method.to_ascii_uppercase
> +    pub fn make_ascii_uppercase(&mut self) {
> +        self.buf.make_ascii_uppercase();
> +    }
> +
> +    /// Returns a copy of this CString where each character is mapped to its
> +    /// ASCII lower case equivalent.
> +    ///
> +    /// ASCII letters 'A' to 'Z' are mapped to 'a' to 'z',
> +    /// but non-ASCII letters are unchanged.
> +    ///
> +    /// 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();
> +
> +        return Ok(s);
> +    }
> +
> +    /// Returns a copy of this CString where each character is mapped to its
> +    /// ASCII upper case equivalent.
> +    ///
> +    /// ASCII letters 'a' to 'z' are mapped to 'A' to 'Z',
> +    /// but non-ASCII letters are unchanged.
> +    ///
> +    /// 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();
> +
> +        return Ok(s);
> +    }
>   }
>   
>   impl Deref for CString {
> 
> base-commit: 41bccc98fb7931d63d03f326a746ac4d429c1dd3
Alice Ryhl Feb. 13, 2024, 2:19 p.m. UTC | #2 
On Tue, Jan 30, 2024 at 3:38 AM Danilo Krummrich <dakr@redhat.com> wrote:
>
> Add functions to convert a CString to upper- / lowercase, either
> in-place or by creating a copy of the original CString.
>
> Naming followes the one from the Rust stdlib, where functions starting
> with 'to' create a copy and functions starting with 'make' perform an
> in-place conversion.
>
> This is required by the Nova project (GSP only Rust successor of
> Nouveau) to convert stringified enum values (representing different GPU
> chipsets) to strings in order to generate the corresponding firmware
> paths. See also [1].
>
> [1] https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/String.20manipulation.20in.20kernel.20Rust
>
> Signed-off-by: Danilo Krummrich <dakr@redhat.com>

Not a deal-breaker, but this comment of mine still applies:

https://lore.kernel.org/rust-for-linux/CAH5fLgiwRDcyaxbcUNY8M1c_w11vkCWyRfqVVrN9Sgc7XYT0xw@mail.gmail.com/

Alice
Danilo Krummrich Feb. 14, 2024, 5:20 p.m. UTC | #3 
On 2/13/24 15:19, Alice Ryhl wrote:
> On Tue, Jan 30, 2024 at 3:38 AM Danilo Krummrich <dakr@redhat.com> wrote:
>>
>> Add functions to convert a CString to upper- / lowercase, either
>> in-place or by creating a copy of the original CString.
>>
>> Naming followes the one from the Rust stdlib, where functions starting
>> with 'to' create a copy and functions starting with 'make' perform an
>> in-place conversion.
>>
>> This is required by the Nova project (GSP only Rust successor of
>> Nouveau) to convert stringified enum values (representing different GPU
>> chipsets) to strings in order to generate the corresponding firmware
>> paths. See also [1].
>>
>> [1] https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/String.20manipulation.20in.20kernel.20Rust
>>
>> Signed-off-by: Danilo Krummrich <dakr@redhat.com>
> 
> Not a deal-breaker, but this comment of mine still applies:
> 
> https://lore.kernel.org/rust-for-linux/CAH5fLgiwRDcyaxbcUNY8M1c_w11vkCWyRfqVVrN9Sgc7XYT0xw@mail.gmail.com/

I missed your mail, gonna send a v3.

- Danilo

> 
> Alice
>
diff mbox series

Patch

diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 7d848b83add4..758bb70d98e9 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -581,6 +581,66 @@  pub fn try_from_fmt(args: fmt::Arguments<'_>) -> Result<Self, Error> {
         // exist in the buffer.
         Ok(Self { buf })
     }
+
+    /// Converts this CString to its ASCII lower case equivalent in-place.
+    ///
+    /// ASCII letters 'A' to 'Z' are mapped to 'a' to 'z',
+    /// but non-ASCII letters are unchanged.
+    ///
+    /// To return a new lowercased value without modifying the existing one, use
+    /// [`to_ascii_lowercase()`].
+    ///
+    /// [`to_ascii_lowercase()`]: #method.to_ascii_lowercase
+    pub fn make_ascii_lowercase(&mut self) {
+        self.buf.make_ascii_lowercase();
+    }
+
+    /// Converts this CString to its ASCII upper case equivalent in-place.
+    ///
+    /// ASCII letters 'a' to 'z' are mapped to 'A' to 'Z',
+    /// but non-ASCII letters are unchanged.
+    ///
+    /// To return a new uppercased value without modifying the existing one, use
+    /// [`to_ascii_uppercase()`].
+    ///
+    /// [`to_ascii_uppercase()`]: #method.to_ascii_uppercase
+    pub fn make_ascii_uppercase(&mut self) {
+        self.buf.make_ascii_uppercase();
+    }
+
+    /// Returns a copy of this CString where each character is mapped to its
+    /// ASCII lower case equivalent.
+    ///
+    /// ASCII letters 'A' to 'Z' are mapped to 'a' to 'z',
+    /// but non-ASCII letters are unchanged.
+    ///
+    /// 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();
+
+        return Ok(s);
+    }
+
+    /// Returns a copy of this CString where each character is mapped to its
+    /// ASCII upper case equivalent.
+    ///
+    /// ASCII letters 'a' to 'z' are mapped to 'A' to 'Z',
+    /// but non-ASCII letters are unchanged.
+    ///
+    /// 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();
+
+        return Ok(s);
+    }
 }
 
 impl Deref for CString {