Re: [PATCH] Documentation/checkpatch: Prefer str_has_prefix over strncmp

From: Jonathan Corbet
Date: Fri Aug 02 2019 - 09:39:02 EST


On Fri, 2 Aug 2019 14:25:37 +0800
Chuhong Yuan <hslester96@xxxxxxxxx> wrote:

> Add strncmp() to Documentation/process/deprecated.rst since
> using strncmp() to check whether a string starts with a
> prefix is error-prone.
> The safe replacement is str_has_prefix().

Is that the *only* use of strncmp()?

> Also add check to the newly introduced deprecated_string_apis
> in checkpatch.pl.
>
> This patch depends on patch:
> "Documentation/checkpatch: Prefer stracpy/strscpy over
> strcpy/strlcpy/strncpy."
>
> Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
> ---
> Documentation/process/deprecated.rst | 8 ++++++++
> scripts/checkpatch.pl | 1 +
> 2 files changed, 9 insertions(+)
>
> diff --git a/Documentation/process/deprecated.rst b/Documentation/process/deprecated.rst
> index 56280e108d5a..22d3f0dbcf61 100644
> --- a/Documentation/process/deprecated.rst
> +++ b/Documentation/process/deprecated.rst
> @@ -109,6 +109,14 @@ the given limit of bytes to copy. This is inefficient and can lead to
> linear read overflows if a source string is not NUL-terminated. The
> safe replacement is stracpy() or strscpy().
>
> +strncmp()
> +---------
> +:c:func:`strncmp` is often used to test if a string starts with a prefix

Please don't use :c:func: anymore; just say strncmp() and the right things
will happen.

Thanks,

jon