KVS/builder/functions.sh
2024-03-07 00:05:10 -05:00

127 lines
2.5 KiB
Bash

#!/bin/bash
COLOR_RESET="\033[0m"
COLOR_BLACK_B="\033[1;30m"
COLOR_RED="\033[0;31m"
COLOR_RED_B="\033[1;31m"
COLOR_GREEN="\033[0;32m"
COLOR_GREEN_B="\033[1;32m"
COLOR_YELLOW="\033[0;33m"
COLOR_YELLOW_B="\033[1;33m"
COLOR_BLUE="\033[0;34m"
COLOR_BLUE_B="\033[1;34m"
COLOR_MAGENTA="\033[0;35m"
COLOR_MAGENTA_B="\033[1;35m"
COLOR_CYAN="\033[0;36m"
COLOR_CYAN_B="\033[1;36m"
readlink /proc/$$/exe | grep -q bash || error "You MUST execute this with Bash!"
log(){
printf '${COLOR_GREEN}Info: %b${COLOR_RESET}\n' "$*"
}
error(){
printf "${COLOR_RED_B}ERR: %b${COLOR_RESET}\n" "$*" >&2 || :
printf "${COLOR_RED}Exiting... ${COLOR_RESET}\n" >&2 || :
exit 1
}
suppress() {
if [ "${FLAGS_debug:-0}" = "${FLAGS_TRUE:-1}" ]; then
"$@"
else
"$@" &>/dev/null
fi
}
get_sector_size() {
fdisk -l "$1" | grep "Sector size" | awk '{print $4}'
}
get_final_sector() {
fdisk -l -o end "$1" | grep "^\s*[0-9]" | awk '{print $1}' | sort -nr | head -n 1
}
is_ext2() {
local rootfs="$1"
local offset="${2-0}"
local sb_magic_offset=$((0x438))
local sb_value=$(dd if="$rootfs" skip=$((offset + sb_magic_offset)) \
count=2 bs=1 2>/dev/null)
local expected_sb_value=$(printf '\123\357')
if [ "$sb_value" = "$expected_sb_value" ]; then
return 0
fi
return 1
}
enable_rw_mount() {
local rootfs="$1"
local offset="${2-0}"
if ! is_ext2 "$rootfs" $offset; then
echo "enable_rw_mount called on non-ext2 filesystem: $rootfs $offset" 1>&2
return 1
fi
local ro_compat_offset=$((0x464 + 3))
printf '\000' |
dd of="$rootfs" seek=$((offset + ro_compat_offset)) \
conv=notrunc count=1 bs=1 2>/dev/null
}
disable_rw_mount() {
local rootfs="$1"
local offset="${2-0}"
if ! is_ext2 "$rootfs" $offset; then
echo "disable_rw_mount called on non-ext2 filesystem: $rootfs $offset" 1>&2
return 1
fi
local ro_compat_offset=$((0x464 + 3))
printf '\377' |
dd of="$rootfs" seek=$((offset + ro_compat_offset)) \
conv=notrunc count=1 bs=1 2>/dev/null
}
shrink_partitions() {
local shim="$1"
fdisk "$shim" <<EOF
d
12
d
11
d
10
d
9
d
8
d
7
d
6
d
5
d
4
q
EOF
}
truncate_image() {
local buffer=35
local sector_size=$(fdisk -l "$1" | grep "Sector size" | awk '{print $4}')
local final_sector=$(get_final_sector "$1")
local end_bytes=$(((final_sector + buffer) * sector_size))
log_info "Truncating image to $(format_bytes "$end_bytes")"
truncate -s "$end_bytes" "$1"
# recreate backup gpt table/header
suppress sgdisk -e "$1" 2>&1 | sed 's/\a//g'
}