pyrox.dev
1{ lib, stdenv, fetchFromGitHub, runtimeShell }:
2
3stdenv.mkDerivation {
4 pname = "flockit";
5 version = "2012-08-11";
6
7 src = fetchFromGitHub {
8 owner = "smerritt";
9 repo = "flockit";
10 rev = "5c2b2092f8edcc8e3e2eb6ef66c968675dbfa686";
11 sha256 = "0vajck9q2677gpn9a4flkyz7mw69ql1647cjwqh834nrcr2b5164";
12 };
13
14 installPhase = ''
15 mkdir -p $out/lib $out/bin
16 cp ./libflockit.so $out/lib
17
18 (cat <<EOI
19 #!${runtimeShell}
20 env LD_PRELOAD="$out/lib/libflockit.so" FLOCKIT_FILE_PREFIX=\$1 \''${@:2}
21 EOI
22 ) > $out/bin/flockit
23 chmod +x $out/bin/flockit
24 '';
25
26 meta = with lib; {
27 description = "LD_PRELOAD shim to add file locking to programs that don't do it (I'm looking at you, rsync!)";
28 longDescription = ''
29 This library and tool exists solely because rsync doesn't have file locking.
30
31 It's not used like a normal library; you don't link against it, and you
32 don't have to patch your source code to use it. It's inserted between your
33 program and its libraries by use of LD_PRELOAD.
34
35 For example:
36
37 $ env LD_PRELOAD=$(nix-build -A pkgs.flockit)/lib/libflockit.so FLOCKIT_FILE_PREFIX=test rsync SRC DEST
38
39 Besides the library a handy executable is provided which can simplify the above to:
40
41 $ $(nix-build -A pkgs.flockit)/bin/flockit test rsync SRC DEST
42
43 Also see the following blog post:
44 https://www.swiftstack.com/blog/2012/08/15/old-school-monkeypatching/
45 '';
46 homepage = "https://github.com/smerritt/flockit";
47 license = licenses.asl20;
48 platforms = platforms.linux;
49 maintainers = [ maintainers.basvandijk ];
50 };
51}