spectrumPackages: update execline backtick uses

execline 2.8.0.0 changed how backtick's options work:

 * -i (exit with the program's error code on failure) and -n (chomp off
   a trailing newline from the captured output) are now the defaults.
 * -E has been introduced, which does importas automatically.

-E is fantastic, because we followed every single use of backtick with
importas.

Even we didn't have -n before, it's okay that chomping will now be
enabled from the default, because in all those cases, there won't be a
trailing newline anyway.

Message-Id: <20210808170439.1372425-1-hi@alyssa.is>
Reviewed-by: sterni <sternenseemann@systemli.org>

3 files changed, 7 insertions, 16 deletions

diff --git a/pkgs/os-specific/linux/spectrum/testhost/default.nix b/pkgs/os-specific/linux/spectrum/testhost/default.nix
index de62f0add67..d81ff8b826e 100644
--- a/pkgs/os-specific/linux/spectrum/testhost/default.nix
+++ b/pkgs/os-specific/linux/spectrum/testhost/default.nix
@@ -52,18 +52,14 @@ let
           #       routers from clients.  Other bits are reserved.
           #  5-6  Last two octets of client's IP (in 100.64.0.0/16).
           #
-          backtick -i router_mac {
+          backtick -E router_mac {
             pipeline { printf %.4x ${toString sys-vms.app.vmID} }
             sed s/^\\(..\\)\\(..\\)$/0A:B3:EC:80:\\1:\\2/
           }
-          backtick -i client_mac {
+          backtick -E client_mac {
             pipeline { printf %.4x ${toString sys-vms.app.vmID} }
             sed s/^\\(..\\)\\(..\\)$/0A:B3:EC:00:\\1:\\2/
           }
-          multisubstitute {
-            importas -iu router_mac router_mac
-            importas -iu client_mac client_mac
-          }
 
           # Create the net VM end, and attach it to the net VM.
           #
@@ -143,12 +139,11 @@ let
           # is allowed to fail because it might already know that, in
           # which case it'll return EEXIST.
           if { modprobe vfio-pci }
-          backtick -in device_id {
+          backtick -E device_id {
             if { dd bs=2 skip=1 count=2 status=none if=''${PCI_PATH}/vendor }
             if { printf " " }
             dd bs=2 skip=1 count=2 status=none if=''${PCI_PATH}/device
           }
-          importas -iu device_id device_id
           foreground {
             redirfd -w 1 /sys/bus/pci/drivers/vfio-pci/new_id
             printf "%s" $device_id
@@ -205,8 +200,7 @@ writeScriptBin "spectrum-testhost" ''
   if { redirfd -w 1 /proc/sys/net/ipv4/ip_forward echo 1 }
 
   importas -iu runtime_dir XDG_RUNTIME_DIR
-  backtick -in TOP { mktemp -dp $runtime_dir spectrum.XXXXXXXXXX }
-  importas -iu top TOP
+  backtick -E top { mktemp -dp $runtime_dir spectrum.XXXXXXXXXX }
   if { echo $top }
   if { rsync -r --chmod=Du+w ${servicesDir}/ ''${top}/service }
   background {
diff --git a/pkgs/os-specific/linux/spectrum/vm/app/default.nix b/pkgs/os-specific/linux/spectrum/vm/app/default.nix
index f8ff480932c..9ffed7e5b13 100644
--- a/pkgs/os-specific/linux/spectrum/vm/app/default.nix
+++ b/pkgs/os-specific/linux/spectrum/vm/app/default.nix
@@ -26,12 +26,11 @@ runCommand "vm-app" rec {
         oneshot
       '';
       up = writeText "net-up" ''
-        backtick -i LOCAL_IP {
+        backtick -E LOCAL_IP {
           pipeline { ip -j link show eth0 }
           pipeline { jq -r ".[0].address | split(\":\") | .[4:6] | \"0x\" + .[]" }
           xargs printf "100.64.%d.%d"
         }
-        importas -iu LOCAL_IP LOCAL_IP
 
         if { ip address add ''${LOCAL_IP}/32 dev eth0 }
         if { ip link set eth0 up }
diff --git a/pkgs/os-specific/linux/spectrum/vm/net/default.nix b/pkgs/os-specific/linux/spectrum/vm/net/default.nix
index 5921b62fcf7..75c86b8f92c 100644
--- a/pkgs/os-specific/linux/spectrum/vm/net/default.nix
+++ b/pkgs/os-specific/linux/spectrum/vm/net/default.nix
@@ -54,12 +54,11 @@ runCommand "vm-net" rec {
 
               # Our IP is encoded in the NIC-specific portion of the
               # interface's MAC address.
-              backtick -i CLIENT_IP {
+              backtick -E CLIENT_IP {
                 pipeline { ip -j link show $INTERFACE }
                 pipeline { jq -r ".[0].address | split(\":\") | .[4:6] | \"0x\" + .[]" }
                 xargs printf "100.64.%d.%d"
               }
-              importas -iu CLIENT_IP CLIENT_IP
 
               if { ip address add 169.254.0.1/32 dev $INTERFACE }
               if { ip link set $INTERFACE up }
@@ -121,7 +120,7 @@ runCommand "vm-net" rec {
       '';
       run = writeScript "connman-run" ''
         #! ${execline}/bin/execlineb -S0
-        backtick -in HARDWARE_INTERFACES {
+        backtick -E HARDWARE_INTERFACES {
           pipeline {
             find -L /sys/class/net -mindepth 2 -maxdepth 2 -name address -print0
           }
@@ -132,7 +131,6 @@ runCommand "vm-net" rec {
           # Extract the interface names from the address file paths.
           awk -F/ "{if (NR > 1) printf \",\"; printf \"%s\", $5}"
         }
-        importas -iu HARDWARE_INTERFACES HARDWARE_INTERFACES
 
         ${connman}/bin/connmand -ni $HARDWARE_INTERFACES
       '';