From b17988134bc1449c8f4c1c8319e463fae5594b0c Mon Sep 17 00:00:00 2001
From: Peter Surda <surda@economicsofbitcoin.com>
Date: Tue, 2 Mar 2021 14:39:19 +0100
Subject: [PATCH] feat: high leve functions for install and update

---
 drive.inc         |  5 ++++-
 install.sh        | 35 ++++++++++++++---------------------
 maas-images.inc   | 41 +++++++++++++++++++++--------------------
 syslinux.inc      | 21 ++++++++++++++++-----
 syslinux_menu.inc | 14 ++++++++++++--
 5 files changed, 67 insertions(+), 49 deletions(-)

diff --git a/drive.inc b/drive.inc
index fe75b43..e06a00c 100644
--- a/drive.inc
+++ b/drive.inc
@@ -52,10 +52,13 @@ function find_unused
 function find_oldest
 {
     local drive="$1"
+    local current="$(grep -E ^serial: /etc/cloud/build.info |cut -d\  -f2)"
     oldest="$(parted -m "$drive" -- print|awk -F: \
+        -v current="root_$current" \
         'BEGIN {min="zzzzz"}
          {if (NR > 2 && $1 >= 2 && $1 <= 4 &&
-                        $6 < min && $6 != "root unused") {
+                        $6 < min && $6 != "root unused" &&
+                        $6 != current) {
              min=$6; part=$1
          }}
          END {print part}')"
diff --git a/install.sh b/install.sh
index b6b4450..18ca160 100644
--- a/install.sh
+++ b/install.sh
@@ -1,25 +1,18 @@
 #!/bin/bash
 
-function setup_bootloader()
-{
-    local dev="$1"
-    check_if_can_overwrite
-    check_if_mounted_or_used_in_lvm_md_crypt
-    wipe_or_nvme_format
-    parted mklabel gpt
-    parted mkpart 1GB EFI
-    parted mkpart 1GB squashfs-1
-    parted mkpart 1GB squashfs-2
-    parted mkpart 1GB squashfs-3
+. install.inc
+
+drive="$1"
+
+if [ ! -b "$drive" ]; then
+    echo "Usage install.sh /dev/wherever"
+    exit 1
+fi
+
+setup_drive "$drive"
+get_streams
+get_latest_maas_id
+download_version "$release_version" "$drive"
+update_syslinux_menu "$drive"
 
-    dd gptmbr.bin
-    mkfs.vfat "$dev"1
-    syslinux "$dev"1
-    mount
-    copy_efi_files
-    create_syslinux_cfg
-    umount
-}
 
-detect_disks
-select_disk
diff --git a/maas-images.inc b/maas-images.inc
index ce5f181..a3280b2 100644
--- a/maas-images.inc
+++ b/maas-images.inc
@@ -6,6 +6,9 @@ OS_VERSION=20.04
 
 function get_streams()
 {
+    if [ -e "$streams" ]; then
+        return 0
+    fi
     streams="$(mktemp)"
     wget -qO "$streams" https://images.maas.io/ephemeral-v3/stable/streams/v1/com.ubuntu.maas:stable:v3:download.json
 }
@@ -23,27 +26,39 @@ function get_checksum()
 {
     local release_version="$1"
     local filename="$2"
+    if [ ! -f "$streams" ]; then
+        return 1
+    fi
     checksum=$(jq -r '.products[]|select(.version=="'"$OS_VERSION"'" and .arch=="amd64" and .kflavor=="generic" and .subarch=="ga-'"$OS_VERSION"'").versions."'"$release_version"'".items."'"$filename"'".sha256' \
         "$streams")
 }
 
-function remove_version()
+function file_url()
 {
-    local version="$1"
-
+    local release_version="$1"
+    local filename="$2"
+    if [ ! -f "$streams" ]; then
+        return 1
+    fi
+    url=$(jq -r '.products[]|select(.version=="'"$OS_VERSION"'" and .arch=="amd64" and .kflavor=="generic" and .subarch=="ga-'"$OS_VERSION"'").versions."'"$release_version"'".items."'"$filename"'".path' \
+        "$streams")
+    url="https://images.maas.io/ephemeral-v3/stable/$url"
 }
 
 function download_and_verify()
 {
-    local url="$1"
-    local checksum="$2"
-    local fname="$3"
+    local release_version="$1"
+    local fname="$2"
+
+    file_url "$release_version" "$fname"
+    checksum "$release_version" "$fname"
 
     wget "$url" -O "$fname"
     sha256sum=$(sha256sum "$fname")
     if [ "$sha256sum" == "$checksum" ]; then
         return 0
     fi
+    rm -f "$fname"
     return 1
 }
 
@@ -54,18 +69,4 @@ function cleanup_temp()
     fi
 }
 
-function download_files()
-{
-    download kernel
-    download initrd
-    download squashfs
-
-    dd if=squashfs of="$partition" bs=1M
-
-    create_options_file
-    update_default
-    delete_oldest_if_needed
-    update_onerror_second_youngest
-}
-
 # vim: set ft=sh:
diff --git a/syslinux.inc b/syslinux.inc
index fa45cb6..c3cd46e 100644
--- a/syslinux.inc
+++ b/syslinux.inc
@@ -1,17 +1,25 @@
 #!/bin/bash
 
-function mount_efi()
+function dev_from_partnum()
 {
     local drive="$1"
-    local partition="$drive"1
+    local partnum="$2"
+    partition="$drive""$partnum"
     if [ ! -b "$partition" ]; then
-        partition="$drive"p1
+        partition="$drive"p"$partnum"
         if [ ! -b "$partition" ]; then
             echo "Can't find first partition for \"$drive\""
 
             exit 1
         fi
     fi
+}
+
+function mount_efi()
+{
+    local drive="$1"
+
+    dev_from_partnum "$drive" 1
 
     unset mnt
     mnt="$(mktemp -d)"
@@ -25,7 +33,7 @@ function mount_efi()
     fi 
 }
 
-function cleanup_mnt()
+function umount_efi()
 {
     umount "$mnt"
     flush
@@ -36,6 +44,9 @@ function install_syslinux()
 {
     local drive="$1"
 
+    dd bs=440 count=1 conv=notrunc \
+        if=/usr/lib/syslinux/mbr/gptmbr.bin of="$drive"
+
     mount_efi "$drive"
 
     # legacy
@@ -48,7 +59,7 @@ function install_syslinux()
     cp syslinux/{mainmenu,syslinux}.cfg "$mnt"/syslinux
     cp syslinux/syslx64.cfg "$mnt"/EFI/BOOT
 
-    cleanup_mnt
+    umount_efi
     syslinux "$partition"
 }
 
diff --git a/syslinux_menu.inc b/syslinux_menu.inc
index e218dea..593b8a2 100644
--- a/syslinux_menu.inc
+++ b/syslinux_menu.inc
@@ -25,7 +25,7 @@ function update_syslinux_menu()
         version_from_partnum "$drive" "$part"
         versions["$version"]=1
         for f in $files; do
-            if [ ! -e "$imagepath"/"$f""$version" ]; then
+            if [ ! -e "$mnt"/"$imagepath"/"$f""$version" ]; then
                 continue
             fi
         done
@@ -38,7 +38,17 @@ APPEND initrd=$imagepath/boot-initrd.$version root=PARTLABEL="rootfs_$version" i
 (EOL)
     done
 
-    cleanup_mnt
+    # find expired
+    for f in $files; do
+        for i in "$mnt"/"$imagepath"/"$f"*; do
+            version="$(basename "$i"|cut -d_ -f2-)"
+            if [ -z "${versions[$version]}" ]; then
+                rm -f $i
+            fi
+        done
+    done
+
+    umount_efi
 }
 
 # vim: set ft=sh: