zfs/scripts
Graham Christensen dda702fd16
bash scripts: use /usr/bin/env for bash shebangs
Not all systems / distros have a `/bin/bash`, and these scripts are
more difficult to run at development time.

For example, my system is NixOS which doesn't have a /bin/bash. This
is not a problem for NixOS building ZFS as a package: the build
environment automatically replaces these shebangs with corrected
paths.

The problem is much more annoying at development time: either the
scripts don't run, or I correct them for my local machine and deal with
a perpetually dirty work tree.

Before committing this patch I confirmed there are existing scripts
which use `/usr/bin/env` to locate bash, so I am thinking this is a
safe transformation.

There are a handful of other shebangs in this repository which don't
work on my system. This patch is useful on its own specifically for
`commitcheck.sh`, otherwise I can't validate my commits before
submission.

Here are the remaining shebangs which NixOS systems won't have:

       1274 #!/bin/ksh -p
         91 #!/bin/ksh
         89 #! /bin/ksh -p
          2 #!/bin/sed -f
          1 #!/usr/bin/perl -w
          1 #!/usr/bin/ksh
          1 #!/bin/nawk -f

plus this which will create an invalid shebang in
`tests/zfs-tests/tests/functional/mv_files/mv_files_common.kshlib`:

        echo "#!/bin/ksh" > $TEST_BASE_DIR/exitsZero.ksh

I chose to leave those alone for now, and gauge the interest in this
much smaller patch first.

The fixes for these are easy enough by simply using `/usr/bin/env ksh`:

         91 #!/bin/ksh
          1 #!/usr/bin/ksh

The fix for the other set is much trickier. Quoting the GNU coreutils
manual:

    Most operating systems (e.g. GNU/Linux, BSDs) treat all text after
    the first space as a single argument. When using env in a script it
    is thus not possible to specify multiple arguments.

and not all `env`'s support arguments.

Mine (GNU Coreutils 8.31) does, though this feature is new since
April 2018, GNU Coreutils 8.30:
https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=668306ed86c8c79b0af0db8b9c882654ebb66db2

and worse, requires the -S argument:

    -S, --split-string=S  process and split S into separate arguments;
                          used to pass multiple arguments on shebang
                          lines

Example:

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A coreutils)/bin/env "sort -nr"
    /nix/[...]-coreutils-8.31/bin/env: ‘sort -nr’: No such file or directory
    /nix/[...]-coreutils-8.31/bin/env: use -[v]S to pass options in shebang lines

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A coreutils)/bin/env "-S sort -nr"
    2
    1

GNU Coreutils says FreeBSD's `env` does, though I wonder if FreeBSD's
would be unhappy with the `-S`:
https://www.gnu.org/software/coreutils/manual/html_node/env-invocation.html#env-invocation

BusyBox v1.30.1 does not, and does not have a `-S`-like option:

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A busybox)/bin/env "sort -nr"
    env: can't execute 'sort -nr': No such file or directory

Toybox 0.8.1 also does not, and also does not have a `-S` option:

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A toybox)/bin/env "sort -nr"
    env: exec sort -nr: No such file or directory

---

At any rate, if this patch merges and the remaining ~1,500 are updated,
the much larger patch should probably include a checkstyle-like test
asserting all new shebangs use `/usr/bin/env`. I also don't mind
dealing with NixOS weirdness if the project would prefer that.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Graham Christensen <graham@grahamc.com>
Closes #9893
2020-02-10 13:13:46 -08:00
..
zfs-images@3331601f6d Add zimport.sh compatibility test script 2014-02-21 12:10:31 -08:00
.gitignore Remove autotools products 2012-08-27 11:47:44 -07:00
Makefile.am Add FreeBSD core handling in zloop.sh 2020-01-02 13:48:06 -08:00
commitcheck.sh bash scripts: use /usr/bin/env for bash shebangs 2020-02-10 13:13:46 -08:00
common.sh.in ZTS: Adopt OpenZFS test analysis script 2018-06-20 14:03:13 -07:00
cstyle.pl OpenZFS 8794 - cstyle generates warnings with recent perl 2017-12-19 12:54:08 -08:00
dkms.mkconf dkms: Enable debuginfo option to be set with zfs sysconfig file 2019-01-18 10:10:24 -08:00
dkms.postbuild Retire legacy test infrastructure 2017-08-15 17:26:38 -07:00
enum-extract.pl Fix free memory calculation on v3.14+ 2018-02-23 08:50:06 -08:00
kmodtool bash scripts: use /usr/bin/env for bash shebangs 2020-02-10 13:13:46 -08:00
make_gitrev.sh Avoid updating zfs_gitrev.h when rev is unchanged 2019-06-06 19:01:41 -07:00
man-dates.sh Correct man page dates 2019-05-08 10:59:32 -07:00
paxcheck.sh Enable shellcheck to run for select scripts 2017-03-09 10:20:15 -08:00
zfs-helpers.sh Adopt pyzfs from ClusterHQ 2018-05-01 10:33:35 -07:00
zfs-tests.sh ZTS: Reverse constrained path lookup order 2020-01-29 11:23:20 -08:00
zfs.sh Update zfs.sh work on FreeBSD 2019-12-19 09:31:16 -08:00
zfs2zol-patch.sed Add libtpool (thread pools) 2017-08-09 15:31:08 -07:00
zimport.sh bash scripts: use /usr/bin/env for bash shebangs 2020-02-10 13:13:46 -08:00
zloop.sh Add FreeBSD core handling in zloop.sh 2020-01-02 13:48:06 -08:00
zol2zfs-patch.sed Add a script to change file names when upstreaming to OpenZFS/illumos 2016-09-29 21:01:50 -07:00