Browser Integration requires setgid and setuid programs, which needs to be done in the system configuration.
This is cleaner than the ad-hoc ways we have to set things up for platforms without a global configuration file.
This change is prompted by the following, admittedly cursed tarball:
```
> curl https://registry.npmjs.org/char-regex/-/char-regex-1.0.2.tgz 2>/dev/null \
| tar -ztv
drw-rw-rw- 0/0 0 2020-02-18 10:50 package
-rw-rw-rw- 0/0 297 2020-02-18 10:50 package/index.d.ts
-rw-rw-rw- 0/0 1920 2020-02-18 10:50 package/index.js
-rw-rw-rw- 0/0 1092 2020-01-31 11:31 package/LICENSE
-rw-rw-rw- 0/0 937 2020-02-18 10:51 package/package.json
-rw-rw-rw- 0/0 713 2020-02-18 10:50 package/README.md
```
The minimal reproducer for the issue is the following derivation trying
to work around the uid 0 issue with `dontMakeSourcesWritable = true`:
```nix
{ stdenv, fetchurl }:
stdenv.mkDerivation {
name = "test";
src = fetchurl {
sha1 = "d744358226217f981ed58f479b1d6bcc29545dcf";
url = "https://registry.npmjs.org/char-regex/-/char-regex-1.0.2.tgz";
};
dontMakeSourcesWritable = true;
installPhase = ''
cp -R . $out
'';
}
```
This currently fails in the following way:
```
these derivations will be built:
/nix/store/pc3jbydl0xcc8nrndf5xkf7hdhpgpb41-test.drv
building '/nix/store/pc3jbydl0xcc8nrndf5xkf7hdhpgpb41-test.drv'...
unpacking sources
unpacking source archive /nix/store/v9p98kqplf4kflmy91p0687xlvr6klb1-char-regex-1.0.2.tgz
source root is package
find: 'package/index.d.ts': Permission denied
find: 'package/index.js': Permission denied
find: 'package/LICENSE': Permission denied
find: 'package/package.json': Permission denied
find: 'package/README.md': Permission denied
/nix/store/6c47azxacncswc1pllzj28zfzqw40d7c-stdenv-linux/setup: line 1311: cd: package: Permission denied
builder for '/nix/store/pc3jbydl0xcc8nrndf5xkf7hdhpgpb41-test.drv' failed with exit code 1
error: build of '/nix/store/pc3jbydl0xcc8nrndf5xkf7hdhpgpb41-test.drv' failed
```
As you can see, the issue is that `$sourceRoot` isn't executable,
prohibiting the call to `cd`. This can be fixed by running
`chmod +x "${sourceRoot}"` before `cd` regardless of
`dontMakeSourcesWritable` in `unpackPhase` since if `chmod` fails, `cd`
would fail as well and we are out of options.
Verified that the workaround works locally.
Another thing to investigate is investigating if we should use
`--no-same-owner` for `tar` and if it helps in this case as well.
See also <https://github.com/Profpatsch/yarn2nix/issues/56>.
Pyudev depends only on a libudev implementation, rather than on
systemd-udevd specifically or on systemd generally. Let's adjust the
dependency list to make it more specific. In particular, this allows
pyudev to build and run with the overlay which substitutes eudev for
udev.
Pyudev is used by the auxiliary trackpad calibration tools included as
part of libinput. Because an enormous number of packages depend on
libinput, this allows a very large number of packages to be used
without systemd. Note that libinput.so does not depend on pyudev or
systemd -- only the trackpad calibration utilities bundled with
libudev use pyudev.