This is commonly the default behavior with -R, but POSIX leaves the
default unspecified.

(cherry picked from commit 10414d4)
Signed-off-by: Domen Kožar <domen@dev.si>

This is not used anywhere.

(cherry picked from commit 1c3ccba)
Signed-off-by: Domen Kožar <domen@dev.si>

Some tar implementations can't auto-detect compression formats, so
they must be specified explicitly.

(cherry picked from commit 43eb7b6)
Signed-off-by: Domen Kožar <domen@dev.si>

…n the system

On a systemd-based Linux distribution: If the user has previously had multi-user Nix installed on the system, removed it and then reinstalled multi-user Nix again the old nix-daemon.service will still be running when `scripts/install-systemd-multi-user.sh` tries to start it which results in nothing being done and the old daemon continuing its run.

When a normal user then tries to use Nix through the daemon the nix binary will fail to connect to the nix-daemon as it does not belong to the currently installed Nix system. See below for steps to reproduce the issue that motivated this change.

$ sh <(curl https://nixos.org/nix/install) --daemon

$ sudo rm -rf /etc/nix /nix /root/.nix-profile /root/.nix-defexpr /root/.nix-channels /home/nix-installer/.nix-profile /home/nix-installer/.nix-defexpr /home/nix-installer/.nix-channels ~/.nix-channels ~/.nix-defexpr/ ~/.nix-profile /etc/profile.d/nix.sh.backup-before-nix /etc/profile.d/nix.sh; sed -i '/added by Nix installer$/d' ~/.bash_profile

$ unset NIX_REMOTE

$ sh <(curl https://nixos.org/nix/install) --daemon

└$ export NIX_REMOTE=daemon

└$ nix-env -iA nixpkgs.hello
installing 'hello-2.10'
error: cannot connect to daemon at '/nix/var/nix/daemon-socket/socket': No such file or directory
(use '--show-trace' to show detailed location information)

└$ sudo systemctl restart nix-daemon.service

└$ nix-env -iA nixpkgs.hello
installing 'hello-2.10'
these paths will be fetched (6.09 MiB download, 27.04 MiB unpacked):
  /nix/store/2g75chlbpxlrqn15zlby2dfh8hr9qwbk-hello-2.10
  /nix/store/aag9d1y4wcddzzrpfmfp9lcmc7skd7jk-glibc-2.27
copying path '/nix/store/aag9d1y4wcddzzrpfmfp9lcmc7skd7jk-glibc-2.27' from 'https://cache.nixos.org'...
copying path '/nix/store/2g75chlbpxlrqn15zlby2dfh8hr9qwbk-hello-2.10' from 'https://cache.nixos.org'...
building '/nix/store/w9adagg6vlikr799nkkqc9la5hbbpgmi-user-environment.drv'...
created 2 symlinks in user environment

(cherry picked from commit a413594)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit e063c71)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 9080d5d)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 9450dec)
Signed-off-by: Domen Kožar <domen@dev.si>

After installing Nix, I found that all the files and directories
initially copied into the store were writable, with mode 644 or 755:

  drwxr-xr-x 9 root root 4096 Dec 31  1969 /nix/store/ddmmzn4ggz1f66lwxjy64n89864yj9w9-nix-2.3.3

The reason is that that's how they were in the unpacked tarball, and
the install-multi-user script used `rsync -p` without doing anything
else to affect the permissions.

The plain `install` script for a single-user install takes care to
do a `chmod -R a-w` on each store path copied.  We could do the same
here with one more command; or we can pass `--chmod` to rsync, to
have it write the files with the desired modes in the first place.

Tested the new `rsync` command on both a Linux machine with a
reasonably-modern rsync (3.1.3) and a Mac with its default, ancient,
rsync 2.6.9, and it works as expected on both.  Thankfully the latter
is just new enough to have `--chmod`, which dates to rsync 2.6.7.

(cherry picked from commit 26851dd)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 46be11b)
Signed-off-by: Domen Kožar <domen@dev.si>

… flags

(cherry picked from commit 9e12b2f)
Signed-off-by: Domen Kožar <domen@dev.si>

Starting macOS 10.15 /nix can't be creasted directly anymore due to the
readonly filesystem, but synthetic.conf was introduced to enable
creating mountpoints or symlinks for special usecases like package
managers.

(cherry picked from commit 0726ad5)
Signed-off-by: Domen Kožar <domen@dev.si>

The default login shell for users on macOS 10.15 changed from bash to
zsh.  So while generally nonstandard we need to configure it to make nix
function out of the box on macOS.

(cherry picked from commit 1020262)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 083bb3b)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit caface1)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit ee89b77)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 04f597c)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 3386575)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit bc24c09)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 477d7c2)
Signed-off-by: Domen Kožar <domen@dev.si>

This should handle installation scenarios we can handle with
anything resembling confidence. Goal is approximating the existing
setup--not enforcing a best-practice...

Approaches (+ installer-handled, - manual) and configs each covers:

+ no change needed; /nix OK on boot volume:
  All pre-Catalina (regardless of T2 or FileVault use)

+ create new unencrypted volume:
  Catalina, pre-T2, no FileVault

+ create new encrypted-at-rest volume:
  Catalina, pre-T2, FileVault
  Catalina, T2, no FileVault

- require user to pre-create encrypted volume
  Catalina, T2, FileVault

(cherry picked from commit 2b0a81d)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit d3df188)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 2a7ea2e)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 90b0c63)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 573ff8d)
Signed-off-by: Domen Kožar <domen@dev.si>

This is used to determine the dependency tree of impure libraries so nix
knows what paths to open in the sandbox.  With the less restrictive
defaults it isn't needed anymore.

(cherry picked from commit afb78eb)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 7f2df90)
Signed-off-by: Domen Kožar <domen@dev.si>

Nix now runs builds with a pseudo-terminal to enable colored build
output.

(cherry picked from commit f6c122a)
Signed-off-by: Domen Kožar <domen@dev.si>

Sadly 10.15 changed /bin/sh to a shim which executes bash, this means it
can't be used anymore without also opening up the sandbox to allow bash.

    Failed to exec /bin/bash as variant for /bin/sh (1: Operation not permitted).

(cherry picked from commit 2e9bc12)
Signed-off-by: Domen Kožar <domen@dev.si>

- --no-channel-add didn't have effect on multi-user installation
- some new flags didn't work at all
- document all installer flags

(cherry picked from commit 1a5ac89)
Signed-off-by: Domen Kožar <domen@dev.si>

(cherry picked from commit 3d3c219)
Signed-off-by: Domen Kožar <domen@dev.si>