From a40921c8018fb8450a4cc7dc1a0bc7fbbdbd0588 Mon Sep 17 00:00:00 2001
From: ptrcnull <git@ptrcnull.me>
Date: Tue, 9 Apr 2024 20:55:01 +0200
Subject: [PATCH] root-enter: upgrade to 11

---
 root-enter/APKBUILD |  4 ++--
 root-enter/enter    | 50 ++++++++++++++++++++++++++++++++++++---------
 2 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/root-enter/APKBUILD b/root-enter/APKBUILD
index d8673e6..6d8b936 100644
--- a/root-enter/APKBUILD
+++ b/root-enter/APKBUILD
@@ -1,7 +1,7 @@
 # Contributor: Patrycja Rosa <alpine@ptrcnull.me>
 # Maintainer: Patrycja Rosa <alpine@ptrcnull.me>
 pkgname=root-enter
-pkgver=10
+pkgver=11
 pkgrel=0
 pkgdesc="enter chroot with mounts"
 url="https://git.ddd.rip/ptrcnull/ptrcports"
@@ -16,5 +16,5 @@ package() {
 }
 
 sha512sums="
-f573f95bf93486f3417e0adfebdabc3a50f8dd7dd16489f3367fc32c93e187ea41daa19b86a17d73a913ddcfb10d1f8cd5b32b1bb376f6ff152e1ae8d2f7e18f  enter
+8f5c61d316624ec599f71c0b4e17a62b3c950fef1895a8a86b978a454b721b56de4049f588005113387647c9850ad879f303b2b3036f65007df364aebe8f00c3  enter
 "
diff --git a/root-enter/enter b/root-enter/enter
index b22f1f5..540d296 100755
--- a/root-enter/enter
+++ b/root-enter/enter
@@ -1,6 +1,9 @@
 #!/bin/sh
 set -eu
 
+USERNAME="${USERNAME:-$(id -u -n)}"
+UNSHARE_CMD="${UNSHARE_CMD:-unshare}"
+
 # make sure we're root
 if [ "$(id -u)" != 0 ]; then
   sucmd="su -c"
@@ -10,19 +13,28 @@ if [ "$(id -u)" != 0 ]; then
     sucmd="sudo"
   fi
 
-  exec $sucmd env HOME="$HOME" USERNAME="$(id -u -n)" "$0" "$@"
+  exec $sucmd \
+    env \
+      HOME="$HOME" \
+      USERNAME="$USERNAME" \
+      UNSHARE_CMD="$UNSHARE_CMD" \
+      WAYLAND_DISPLAY="$WAYLAND_DISPLAY" \
+      DISPLAY="$DISPLAY" \
+      XDG_RUNTIME_DIR="$XDG_RUNTIME_DIR" \
+      DBUS_SESSION_BUS_ADDRESS="$DBUS_SESSION_BUS_ADDRESS" \
+    "$0" "$@"
 fi
 
 # and make sure we're in a separate mount namespace
 if [ "$(readlink /proc/$$/ns/mnt | cut -d: -f2)" = "$(readlink /proc/1/ns/mnt | cut -d: -f2)" ]; then
-  exec unshare -m "$0" "$@"
+  exec $UNSHARE_CMD --keep-caps -m "$0" "$@"
 fi
 
 bindpoints="/etc/resolv.conf"
 command=""
 user="$USERNAME"
 
-while getopts "be:u:c:" opt; do
+while getopts "bde:u:c:" opt; do
   case $opt in
     'b') bindpoints="
       $bindpoints
@@ -31,6 +43,11 @@ while getopts "be:u:c:" opt; do
       $HOME/packages
       $HOME/.abuild
       " ;;
+    'd') bindpoints="
+      $bindpoints
+      $XDG_RUNTIME_DIR
+      /tmp
+      " ;;
     'e') bindpoints="$bindpoints $OPTARG" ;;
     'u') user="$OPTARG" ;;
     'c') command="$OPTARG" ;;
@@ -47,11 +64,14 @@ if [ ! -d "$dest" ]; then
   exit 1
 fi
 
-if [ ! -x "$dest"/bin/sh ]; then
+if ! [ -x "$dest"/bin/sh -o -L "$dest"/bin/sh ]; then
   echo "$dest does not contain executable /bin/sh"
   exit 1
 fi
 
+# do stupid path fixup
+export PATH="/bin:/sbin:/usr/bin:/usr/sbin:$PATH"
+
 mount -t proc proc "$dest"/proc
 mount -t sysfs sysfs "$dest"/sys
 mount -t tmpfs tmpfs "$dest"/tmp
@@ -61,16 +81,23 @@ if grep -q devtmpfs /proc/filesystems; then
 else
   mount -t tmpfs tmpfs "$dest"/dev
 
-  if [ -x "$dest"/sbin/mdev ]; then
+  if [ -x "$dest"/sbin/mdev -o -L "$dest"/sbin/mdev ]; then
     echo "devtmpfs not supported - running 'mdev -s' instead"
-    chroot "$dest" /sbin/mdev -s
+    chroot "$dest" /sbin/mdev -sv
   else
     echo "devtmpfs not supported - devices need to be created manually"
   fi
 fi
+mkdir -p "$dest"/dev/pts "$dest"/dev/shm
 mount -t devpts devpts "$dest"/dev/pts
 mount -t tmpfs tmpfs "$dest"/dev/shm
 
+# workaround for shitty android-based stuff
+if ! [ -f /etc/resolv.conf ]; then
+  # remove /etc/resolv.conf from bindpoints
+  bindpoints="${bindpoints#/etc/resolv.conf}"
+fi
+
 for bindpoint in $bindpoints; do
   if [ -f "$bindpoint" ]; then
     touch "$dest"/"$bindpoint"
@@ -78,7 +105,7 @@ for bindpoint in $bindpoints; do
     mkdir -p "$dest"/"$bindpoint"
   fi
 
-  mount --bind "$bindpoint" "$dest"/"$bindpoint"
+  mount -o bind "$bindpoint" "$dest"/"$bindpoint"
 done
 
 # if running on chromeos, fixup symlink exec
@@ -96,10 +123,13 @@ if [ -e "/run/chrome" ]; then
   fi
 fi
 
+mount -o bind "$dest" /mnt
+pivot_root /mnt /mnt/mnt
+
 if [ "$command" ]; then
-  exec chroot "$dest" su $user -c "$command"
+  exec su $user -c "$command"
 elif [ "$#" -gt 0 ]; then
-  exec chroot "$dest" su $user -c "$*"
+  exec su $user -c "$*"
 else
-  exec chroot "$dest" login -f $user
+  exec login -p -f $user
 fi