release: Add a helper script for common tools

[bnovkov]

Summary

Add a helper script that populates variables used to invoke several tools.
This is also the first step towards cleaning up several inconsistencies
related to tool invocation in various release scripts (e.g. ${MAKEFS} vs makefs).

Sponsored by: Klara, Inc.
Sponsored by: The FreeBSD Foundation

[des]

release/scripts/tools.subr

36

This can be reduced to

: ${ETDUMP:=etdump}

[emaste]

release/scripts/tools.subr

9

[bnovkov]

Address @des 's and @emaste 's comments.

release/scripts/tools.subr

36

Thank you, fixed.

[emaste]

It's OK to omit the license boilerplate and have just the SPDX now too, i.e. remove Redistribution and use ... SUCH DAMAGE. Just noticed since this file only has three lines of content now.

[markj]

Is this the right place to interpose if I want to add a flag to every use of one of these tools? For instance, in reproducible build mode, mkimg should be invoked with the new -R flag; should I just write something like

if [ -n "$REPRODUCIBLE_BUILD" ]; then
    MKIMG="${MKIMG} -R"
fi

here?

[bnovkov]

Remove license boilerplate

[bnovkov]

In D51038#1165125, @emaste wrote:

It's OK to omit the license boilerplate and have just the SPDX now too, i.e. remove Redistribution and use ... SUCH DAMAGE. Just noticed since this file only has three lines of content now.

Done, thank you!

In D51038#1165391, @markj wrote:

Is this the right place to interpose if I want to add a flag to every use of one of these tools? For instance, in reproducible build mode, mkimg should be invoked with the new -R flag; should I just write something like

if [ -n "$REPRODUCIBLE_BUILD" ]; then
    MKIMG="${MKIMG} -R"
fi

here?

Yes, this is a good spot to add such flags.
Should we introduce variables like MKIMGARGS make this a little bit clearer?

[markj]

In D51038#1165439, @bnovkov wrote:

In D51038#1165125, @emaste wrote:

It's OK to omit the license boilerplate and have just the SPDX now too, i.e. remove Redistribution and use ... SUCH DAMAGE. Just noticed since this file only has three lines of content now.

Done, thank you!

In D51038#1165391, @markj wrote:

Is this the right place to interpose if I want to add a flag to every use of one of these tools? For instance, in reproducible build mode, mkimg should be invoked with the new -R flag; should I just write something like

if [ -n "$REPRODUCIBLE_BUILD" ]; then
    MKIMG="${MKIMG} -R"
fi

here?

Yes, this is a good spot to add such flags.
Should we introduce variables like MKIMGARGS make this a little bit clearer?

Probably yes, embedding flags directly in MKIMG is fragile, since the caller might reasonably override MKIMG to point to a different executable.