[Buildroot] [PATCH v2] support/download/file: fix file:// protocol handling

[Yann E. MORIN <yann.morin.1998@free.fr>]

Angelo, All,

Thanks for the respin.

On 2018-05-08 15:28 +0200, Angelo Compagnucci spake thusly:
> When a file is used a source for download using the file:// protocol, a
> malformed url is passed to the file download script which then crashes.
> Following an example of a wrong path passed to the script:
> 
> eval cp -v ''\''file:///home/angelo/DEV/TOOLCHAINSarmv7-eabihf--glibc--bleeding-edge-2017.11-1.tar.bz2'\''' ''\''/home/angelo/DEV/BUILDROOT/br_qemu_arm/build/.armv7-eabihf--glibc--bleeding-edge-2017.11-1.tar.bz2.f403PT/output'\'''.
> 
> Path passed to cp lacks of a / between dir and file part of the url,
> moreover it presents a wrong file:// prefix.

Well, the misisng / is indeed incorrect.

However, the leading protocol is expected: the dl-wrapper calls all
backend scripts with the exact same set of options and semantics. It's
is then up to the backend scripts to interpret that as they see fit.

So, it is not "semantically wrong"; it *is* correct.

The bug lies in the fact that the 'file' backend did not strip out the
protocol part when calling the actual tool; we missed that during the
download overhaul.

Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

Regards,
Yann E. MORIN.

> Fixes:
> 
> cp: cannot stat
> 'file:///home/angelo/DEV/TOOLCHAINSarmv7-eabihf--glibc--bleeding-edge-2017.11-1.tar.bz2':
> No such file or directory
> 
> Signed-off-by: Angelo Compagnucci <angelo@amarulasolutions.com>
> ---
>  support/download/file | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/support/download/file b/support/download/file
> index fefd6d2..6dd37b0 100755
> --- a/support/download/file
> +++ b/support/download/file
> @@ -40,4 +40,4 @@ _localfiles() {
>      eval ${LOCALFILES} "${@}"
>  }
>  
> -_localfiles ${verbose} "'${dir}${file}'" "'${output}'"
> +_localfiles ${verbose} "'${dir##file://}/${file}'" "'${output}'"
> -- 
> 2.7.4
> 

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