Last commit made the script break on macOS.
From `man sed` (On Linux):
```
-E, -r, --regexp-extended
use extended regular expressions in the script (for portability use POSIX -E).
```
This reverts commit 1806504983.
In Buster, APT has built‐in support for HTTPS repos (since version 1.5).
The ca-certificates package is already included in the modified file, so
this commit shouldn’t break anything.
* bash variables in build-docker.sh are wrapped by curly brackets
* Ensure presence of config file while running build-docker.sh
* Do not assume that build-docker.sh is run from the repository root directory
* Mount config file in predictable location in docker container
Turning off IPv6 by aliasing `net-pf-10` to `off` does not work anymore.
Also, turning off IPv6 on system level breaks apps depending on IPv6
loopback or IPv6 link-local addresssing and creates issues in both
dual-stack and IPv6-only environments.
Signed-off-by: Ondřej Caletka <ondrej@caletka.cz>
Added a handy message to make it clear that compiling on a 64 bit OS is causing issues. After spending over an hour of troubleshooting think it should be made clearer as it'll affect quite a few users.
With the Qemu version shipped with Debian Stretch, the `man-db` package
being installed for Buster in the image triggers many of these errors:
qemu: Unsupported syscall: 383
This is a manifestation of the following bug:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=891109
This is resolved in the current Qemu version shipped with Debian Buster.
The `(..)/raspberrypi-kernel/changelog.Debian.gz` file is not guaranteed
to be present in the built `ROOTFS_DIR`, for example when building very
minimal images without package documentation. In these cases, the `firmware`
variable will be left empty and the subsequent calls to `curl` will return
large 404 HTML content from GitHub.
Instead, simply check if the changelog file exists before using it.
* SC1091: the `config` file might not be present, which is normal.
* SC2086: Double quote to prevent globbing and word splitting.
Tested clean output using: `find -name "*.sh" -exec shellcheck -x {} \;`
