[U-Boot] [RFC, PATCH v4 05/16] env: fat: add U-Boot environment context support

[Wolfgang Denk <wd@denx.de>]

Dear AKASHI Takahiro,

In message <20190717082525.891-6-takahiro.akashi@linaro.org> you wrote:
> Please note that the aim of this patch is to illustrate how we can
> extend the existing backing storage drivers for env interfaces to
> support U-Boot environment context.
>
> We will be able to support more devices as well as more contexts
> in a similar way. Existing drivers still work exactly in the same
> way as before while they are not extended yet.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
>  env/fat.c | 103 ++++++++++++++++++++++++++++++++++++++++++++----------
>  1 file changed, 84 insertions(+), 19 deletions(-)
>
> diff --git a/env/fat.c b/env/fat.c
> index 7f74c64dfe7e..e4a672d2730a 100644
> --- a/env/fat.c
> +++ b/env/fat.c
> @@ -30,23 +30,44 @@
>  # endif
>  #endif
>  
> +static struct evn_fat_context {
> +	char *interface;
> +	char *dev_and_part;
> +	char *file;
> +} fat_context[ENVCTX_COUNT] = {
> +#if defined(CONFIG_ENV_FAT_INTERFACE) && \
> +	defined(CONFIG_ENV_FAT_DEVICE_AND_PART) && defined(CONFIG_ENV_FAT_FILE)
> +	[ENVCTX_UBOOT] = {
> +		CONFIG_ENV_FAT_INTERFACE,
> +		CONFIG_ENV_FAT_DEVICE_AND_PART,
> +		CONFIG_ENV_FAT_FILE,
> +	},
> +#endif
> +};

Does it make sense to define this in a FAT specific way? I guess we
could come up with a common structure that covers all supported
storage devices and use this here.

Also, the "#if defined" looks really dangerous to me, as missing
#defines will go unnoticed, and in the end you are accessing
uninitialized data... 

Did you review the patchset for memory leaks? 


Best regards,

Wolfgang Denk

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