chroot-here.sh v1.0

1 files changed, 219 insertions, 0 deletions

diff --git a/tools/chroot-here.sh b/tools/chroot-here.sh
new file mode 100755
index 0000000..b8721b3
--- /dev/null
+++ b/tools/chroot-here.sh
@@ -0,0 +1,219 @@
+#!/bin/bash
+
+# This is a personal script by tomboy64.
+# Copyright 2016 tomboy64.
+# Published under the BSD-3-Clause.
+
+# v1.0
+
+function helpprint() {
+  echo
+  echo "Usage:"
+  echo "ARCH=(arm|arm64|x86|x86_64) chroot-here.sh STAGE3FILE"
+  echo "STAGE3FILE can be any stage3-tarball."
+  echo "ARCH must be one of arm, arm64, x86 or x86_64."
+  echo
+  echo "In general it may name any specific arch you have support for in /etc/binfmt.d."
+  echo "(In case you add more, DO NOT ADD YOUR HOSTS ARCH THERE!"
+  echo
+  echo "BEWARE: THIS SCRIPT GIVES THE CHOICE TO ERASE THE CWD!"
+  echo
+  exit 0
+}
+
+function quit() {
+  echo
+  echo -n "Fatal error: "
+  echo "$@"
+  exit 1
+}
+
+function cntdwn() {
+  local start=10
+  if [[ $1 -ge 0 ]]
+  then
+    start=$1
+  fi
+  echo
+  for i in $(seq "${start}" -1 0)
+  do
+    echo -n "${i} "
+    sleep 1s
+  done
+  echo
+}
+
+function mountDir() {
+  local dir=$1
+  echo -n "Checking ${dir} ... "
+  if [[ ! -d "./${dir}" ]]
+  then
+    echo -n "creating ... "
+    mkdir -p "${dir}" || quit "Creation of ${dir} failed."
+  fi
+  if [[ $(mount | grep "${PWD}" | grep -c "${dir} type") -ge 1 ]]
+  then
+    echo "already mounted."
+  else
+    echo -n "mounting ... "
+    mount --bind "/${dir}" "${dir}" || quit "Couldn't mount ${dir}."
+    echo "done."
+  fi
+}
+
+function umountDir() {
+  local dir=$1
+  echo -n "Unmounting ${dir} ... "
+  umount "${PWD}/${dir}" 2&>/dev/null
+  echo "done."
+}
+
+if [[ $(echo "$@" | grep -c "\-\-help") -gt 0 ]]; then
+  helpprint
+fi
+
+case ${ARCH} in
+  arm)
+    ARCH_FULL=arm
+    ;;
+  arm64)
+    ARCH_FULL=aarch64
+    ;;
+  x86)
+    ARCH_FULL=x86
+    ;;
+  amd64)
+    ARCH_FULL=x86_64
+    ;;
+  *)
+    quit "No suitable ARCH given: ${ARCH}."
+    ;;
+esac
+
+STAGE3_PATH=$(dirname "$1")
+STAGE3_FILE=$(basename "$1")
+
+# various preliminary checks
+if [[ ${ARCH_FULL} == x86 || ${ARCH} == amd64 ]]; then
+  echo "No binfmt support necessary."
+elif [[ $(mount | grep -c '^binfmt_misc') -eq 0 ]]
+then
+  quit "binfmt_misc support missing."
+elif [[ $(grep -c ":${ARCH_FULL}:" /etc/binfmt.d/*) -eq 0 ]]
+then
+  quit "Can't find support for ${ARCH_FULL} in /etc/binfmt.d/."
+elif [[ $(grep -c ":${ARCH_FULL}:" /etc/binfmt.d/*) -gt 1 ]]
+then
+  quit "Support for ${ARCH_FULL} ambiguous in /etc/binfmt.d/."
+else
+  QEMU_BIN=$(grep ":${ARCH_FULL}:" /etc/binfmt.d/* | awk -F ':' '{print $7}')
+fi
+
+if [[ ${ARCH_FULL} == x86 || ${ARCH} == amd64 ]]; then
+  echo "No Qemu needed either."
+elif [[ ! -f "${QEMU_BIN}" ]]
+then
+  quit "Can't find ${QEMU_BIN}. Is it available?"
+elif [[ $(LC_ALL=C ldd "${QEMU_BIN}" | grep -c "not a dynamic executable") -ne 1 ]]
+then
+  quit "The qemu executable (${QEMU_BIN}) is not statically linked."
+elif [[ ${PWD} == '/' ]]
+then
+  quit "You a mad fella. Don't run this in '/'!"
+fi
+
+if [[ ${EUID} -ne 0 ]]
+then
+  quit "You need to run this as root."
+fi
+
+if [[ -z "${STAGE3_PATH}" ]]
+then
+  STAGE3_PATH="${PWD}"
+fi
+if [[ -z "${STAGE3_FILE}" ]]
+then
+  echo -n "No stage3 given; attempt to locate newest available in ${STAGE3_PATH} ..."
+  STAGE3_FILE=$(basename "$(find "${STAGE3_PATH}" -name 'stage3-'"${ARCH}"'-*.tar.bz2' | sort -r | head -n1)")
+  echo " done."
+fi
+if [[ ! -f "${STAGE3_PATH}/${STAGE3_FILE}" ]]
+then
+  echo "No stage3 available (${STAGE3_PATH}/${STAGE3_FILE})."
+fi
+
+# MAKE SURE NONE OF THOSE PATHS IS PREPENDED WITH A /!
+MOUNT_PATHS=( usr/portage proc sys dev dev/pts dev/shm )
+
+#if [[ -d "./${ARCH}-chroot" ]]
+#then
+  echo -n "Erase './'? [y/N] "
+  read -n1 -r response
+  if [[ "${response}" == "y" ]]
+  then
+    echo
+
+    idx=$(( ${#MOUNT_PATHS[@]} - 1 ))
+    while [[ ${idx} -ge 0 ]]
+    do
+      umountDir "./${MOUNT_PATHS[idx]}"
+      idx=$(( idx - 1 ))
+    done
+
+    if [[ $(mount | grep -c "${PWD}") -gt 0 ]]
+    then
+      quit "Not all mounts from ${PWD} removed."
+    fi
+
+    if [[ $(find . | head -n2 | wc -l) -gt 1 ]]; then
+      echo -n "Erasing ... "
+        rm -r ./* || quit "Erasing ${PWD} failed."
+      echo "done."
+    fi
+
+    #mkdir "${ARCH}-chroot" || quit "mkdir ${ARCH}-chroot"
+    #cd "${ARCH}-chroot" || quit "${ARCH}-chroot could not be entered."
+    #echo "Entered ${PWD}"
+
+    if [[ -f "${STAGE3_PATH}/${STAGE3_FILE}" ]]; then
+      echo -n "Extracting stage3 ... "
+      tar xf "${STAGE3_PATH}/${STAGE3_FILE}" || quit "Extraction of ${STAGE3_PATH}/${STAGE3_FILE} failed."
+     echo "done."
+    fi
+
+  fi
+#  else
+
+#    cd "${ARCH}-chroot" || quit "${ARCH}-chroot could not be entered."
+#    echo "Entered ${PWD}"
+#  fi
+#fi
+
+
+for i in "${MOUNT_PATHS[@]}"
+do
+  mountDir "${i}"
+done
+
+cp -v /etc/resolv.conf etc/ || quit "Couldn't copy resolv.conf"
+if [[ ${ARCH_FULL} != x86 && ${ARCH} != amd64 ]]; then
+  cp -v "${QEMU_BIN}" ".$(dirname "${QEMU_BIN}")" || quit "Couldn't copy qemu binary."
+fi
+  cat <<EOF >> etc/portage/make.conf || quit "Couldn't write to etc/portage/make.conf."
+MAKEOPTS="-j5"
+EMERGE_DEFAULT_OPTS="--verbose --autounmask-write --nospinner --keep-going -j5 --load-average=5 --verbose-conflict"
+PYTHON_SINGLE_TARGET="python3_4"
+PYTHON_TARGETS="python2_7 python3_3 python3_4 python3_5 pypy pypy2"
+EOF
+if [[ ${ARCH_FULL} == x86 ]]; then
+  PS1="chroot${PS1}" linux32 chroot ./ /bin/bash --login || quit "Chrooting failed."
+else
+  chroot ./ /bin/bash --login || quit "Chrooting failed."
+fi
+
+idx=$(( ${#MOUNT_PATHS[@]}-1 ))
+while [[ ${idx} -ge 0 ]]
+do
+  umountDir "${MOUNT_PATHS[idx]}"
+  idx=$(( idx - 1 ))
+done