[libcamera-devel] [PATCH 4/4] libcamera: file: Create the file on open() if it doesn't exist

[Kieran Bingham]

Hi Laurent,

On 12/07/2020 15:44, Laurent Pinchart wrote:
> When a file is opened in WriteOnly or ReadWrite mode, create it if it
> doesn't exist.
> 

Indeed, this solved my issue when using this series before.

Thanks!

Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
>  src/libcamera/file.cpp | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/src/libcamera/file.cpp b/src/libcamera/file.cpp
> index 8bd109090919..77701666e438 100644
> --- a/src/libcamera/file.cpp
> +++ b/src/libcamera/file.cpp
> @@ -148,8 +148,9 @@ bool File::exists() const
>   * \param[in] mode The open mode
>   *
>   * This function opens the file specified by fileName() in \a mode. If the file
> - * doesn't exist and the mode is WriteOnly or ReadWrite, this
> - * function will attempt to create the file.
> + * doesn't exist and the mode is WriteOnly or ReadWrite, this function will
> + * attempt to create the file with initial permissions set to 0666 (modified by
> + * the process' umask).
>   *
>   * The error() status is updated.
>   *
> @@ -163,8 +164,10 @@ bool File::open(File::OpenMode mode)
>  	}
>  
>  	int flags = (mode & ReadWrite) - 1;
> +	if (mode & WriteOnly)

This looks a bit awkward, as it's actually WriteOnly or ReadWrite (i.e.
it's not 'Write .. Only') because we know the bit will be set in both
cases ... but that is detailed above in the function comment anyway, so
this is fine, and I'm sure if anyone was looking they'd figure out it
works for RW files too :)

In otherwords, it's only the use of the word 'only' in the enum that's
awkward, but not something worthy of a change of the enum.


> +		flags |= O_CREAT;
>  
> -	fd_ = ::open(name_.c_str(), flags);
> +	fd_ = ::open(name_.c_str(), flags, 0666);
>  	if (fd_ < 0) {
>  		error_ = -errno;
>  		return false;
> 

-- 
Regards
--
Kieran