[OS-BUILD PATCHv2] redhat/configs: Change script interpreter to /bin/bash

[Benjamin Poirier (via Email Bridge)]

From: Benjamin Poirier

redhat/configs: Change script interpreter to /bin/bash

Upstream-status: RHEL-only
Bugzilla: https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3668

When running `make dist-configs` on a system where /bin/sh is dash (rather
than bash), the command fails with:

[...]
Building .../redhat/configs/kernel-riscv64-rt-debug-fedora.config ...
Building .../redhat/configs/kernel-riscv64-rt-debug-fedora.config complete
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
./generate_all_configs.sh: 26: Bad substitution
head: cannot open '.../redhat/configs/kernel-6.14.0*.config' for reading: No such file or directory
cat: '.../redhat/configs/kernel-6.14.0*.config': No such file or directory
Processing .../redhat/configs/kernel-6.14.0*.config ...
.../Makefile:750: arch//Makefile: No such file or directory
make[3]: *** No rule to make target 'arch//Makefile'.  Stop.
make[2]: *** [Makefile:263: __sub-make] Error 2
make[1]: *** [Makefile:564: dist-configs] Error 1
make[1]: Leaving directory '.../redhat'
make: *** [makefile:12: dist-configs] Error 2

The problem is due to the following substitution:
${i:$specpackage_name_len}

If we remove the shellcheck ignore, shellcheck explains:
SC3057 (warning): In POSIX sh, string indexing is undefined.

Since there are already many other scripts under redhat/ which use
/bin/bash as their interpreter, fix this problem by changing the
interpreter for this script to use bash as well.

We can then remove the shellcheck ignore but this results in another
message:
SC2001 (style): See if you can use ${variable//search/replace} instead.

The code is restructured as suggested.

Signed-off-by: Benjamin Poirier

diff --git a/redhat/configs/generate_all_configs.sh b/redhat/configs/generate_all_configs.sh
index blahblah..blahblah 100755
--- a/redhat/configs/generate_all_configs.sh
+++ b/redhat/configs/generate_all_configs.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash

# Adjusts the configuration options to build the variants correctly

@@ -22,9 +22,9 @@ fi
 # The +1 is to remove the - at the end of the SPECPACKAGE_NAME string
 specpackage_name_len=$((${#SPECPACKAGE_NAME} + 1))
 for i in "${SPECPACKAGE_NAME}"*-"$FLAVOR".config; do
-	# shellcheck disable=SC3057
-	NEW=${SPECPACKAGE_NAME}-"$SPECRPMVERSION"-$(echo "${i:$specpackage_name_len}" | sed s/-"$FLAVOR"//)
-	mv "$i" "$NEW"
+	variant=${i:$specpackage_name_len}
+	variant=${variant/-$FLAVOR}
+	mv "$i" "$SPECPACKAGE_NAME-$SPECRPMVERSION-$variant"
 done

rm -f kernel-*-"$SECONDARY".config

--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3668

[Prarit Bhargava (via Email Bridge)]

From: Prarit Bhargava on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3668#note_2326778...

For Fedora and RHEL this should be /usr/bin/bash IIRC.

[Benjamin Poirier (via Email Bridge)]

From: Benjamin Poirier on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3668#note_2328325...

On my Fedora and RHEL-9.5 systems, `/bin` is a symlink to `/usr/bin` so I
don't think it makes a practical difference. Also, there is currently no
consistency for the scripts in the redhat directory:
```
$ git grep -h '^#!.*bash' -- redhat/ | sort | uniq -c
      4 #! /bin/bash
     19 #!/bin/bash
      3 #!/usr/bin/bash
      3 #!/usr/bin/env bash
```

[Prarit Bhargava (via Email Bridge)]

From: Prarit Bhargava on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3668#note_2330985...

I believe this will result in an rpm warning if I'm not mistaken.

[Benjamin Poirier (via Email Bridge)]

From: Benjamin Poirier on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/3668#note_2332342...

Looking in the [build log](https://s3.amazonaws.com/arr-cki-prod-trusted-
artifacts/trusted-
artifacts/1650768901/build_x86_64/9011705058/artifacts/build.log) from one of
the [pipeline jobs](https://gitlab.com/redhat/red-hat-ci-tools/kernel/cki-
internal-pipelines/cki-trusted-contributors/-/jobs/9011705058), is this the
kind of warning you are talking about:
```
mangling shebang in /usr/libexec/kselftests/net/altnames.sh from /bin/bash to
#!/usr/bin/bash
```
That warning is not printed for generate_all_configs.sh, perhaps because that
script is not part of any .rpm package. But anyways, I'll change the
interpreter.