nixpkgs/pkgs/tools/backup/flockit/default.nix
Jörg Thalheim dadc7eb329
treewide: use runtimeShell instead of stdenv.shell whenever possible
Whenever we create scripts that are installed to $out, we must use runtimeShell
in order to get the shell that can be executed on the machine we create the
package for. This is relevant for cross-compiling. The only use case for
stdenv.shell are scripts that are executed as part of the build system.
Usages in checkPhase are borderline however to decrease the likelyhood
of people copying the wrong examples, I decided to use runtimeShell as well.
2019-02-26 14:10:49 +00:00

51 lines
1.6 KiB
Nix

{ stdenv, fetchFromGitHub, runtimeShell }:
stdenv.mkDerivation rec {
name = "flockit-${version}";
version = "2012-08-11";
src = fetchFromGitHub {
owner = "smerritt";
repo = "flockit";
rev = "5c2b2092f8edcc8e3e2eb6ef66c968675dbfa686";
sha256 = "0vajck9q2677gpn9a4flkyz7mw69ql1647cjwqh834nrcr2b5164";
};
installPhase = ''
mkdir -p $out/lib $out/bin
cp ./libflockit.so $out/lib
(cat <<EOI
#!${runtimeShell}
env LD_PRELOAD="$out/lib/libflockit.so" FLOCKIT_FILE_PREFIX=\$1 \''${@:2}
EOI
) > $out/bin/flockit
chmod +x $out/bin/flockit
'';
meta = with stdenv.lib; {
description = "LD_PRELOAD shim to add file locking to programs that don't do it (I'm looking at you, rsync!)";
longDescription = ''
This library and tool exists solely because rsync doesn't have file locking.
It's not used like a normal library; you don't link against it, and you
don't have to patch your source code to use it. It's inserted between your
program and its libraries by use of LD_PRELOAD.
For example:
$ env LD_PRELOAD=$(nix-build -A pkgs.flockit)/lib/libflockit.so FLOCKIT_FILE_PREFIX=test rsync SRC DEST
Besides the library a handy executable is provided which can simplify the above to:
$ $(nix-build -A pkgs.flockit)/bin/flockit test rsync SRC DEST
Also see the following blog post:
https://www.swiftstack.com/blog/2012/08/15/old-school-monkeypatching/
'';
homepage = https://github.com/smerritt/flockit;
license = licenses.asl20;
platforms = platforms.linux;
maintainers = [ maintainers.basvandijk ];
};
}