From 6ecdd2c54bbb26259f898e55ec672bc7438a356a Mon Sep 17 00:00:00 2001
From: William Petit <wpetit@cadoles.com>
Date: Thu, 11 Jan 2024 09:59:55 +0100
Subject: [PATCH] feat: automatically create /data mountpoint with available
 disk free space

---
 .../99-emissary-create-data-partition.sh      | 79 +++++++++++++++++++
 packages.txt                                  |  6 +-
 2 files changed, 84 insertions(+), 1 deletion(-)
 create mode 100644 misc/common/uci-defaults/99-emissary-create-data-partition.sh

diff --git a/misc/common/uci-defaults/99-emissary-create-data-partition.sh b/misc/common/uci-defaults/99-emissary-create-data-partition.sh
new file mode 100644
index 0000000..27c0661
--- /dev/null
+++ b/misc/common/uci-defaults/99-emissary-create-data-partition.sh
@@ -0,0 +1,79 @@
+#!/bin/sh
+
+MIN_DISK_SPACE_MB=1000
+
+list_disks() {
+    lsblk -o NAME -r -d -n
+}
+
+main() {
+    local disks=$(list_disks)
+
+    local found_free_space=0
+    local found_device=""
+
+    for device_name in ${disks}; do
+        local device="/dev/${device_name}"
+        echo "Checking disk '$device'..."
+        
+        local disk_free_space="$(parted $device unit MB print free 2>/dev/null | grep 'Free Space' | tail -n1 | awk '{ print $3 }')"
+        disk_free_space=${disk_free_space%MB}
+        disk_free_space=$(printf '%.0f' "${disk_free_space:-0}")
+        
+        echo "Free space on disk: ${disk_free_space}"
+
+        if [ ! -z "${disk_free_space}" ]; then
+            if [ ${disk_free_space} -gt ${found_free_space} ]; then
+                found_free_space=${disk_free_space}
+                found_device=${device}
+            fi
+        fi
+    done
+
+    if [ -z "${found_device}" ] || [ ${MIN_DISK_SPACE_MB} -gt ${found_free_space} ]; then
+        echo "No device with sufficient remaining disk space, exiting."
+        exit 1
+    fi
+
+    echo "Creating new partition on '${found_device}' with remaining disk free space"
+
+    local last_partition_end_mb=$(parted "$found_device" unit MB print | awk '/^ [0-9]+ / {start=$3} END {print int(start)}')
+    
+    if [ "${last_partition_end_mb}" != "0" ]; then
+        parted -s "${found_device}" -f -a opt mkpart primary "${last_partition_end_mb}MB" '100%'
+    else
+        parted -s "${found_device}" -f -a opt mkpart primary '0%' '100%'
+    fi
+
+    sync
+
+    local last_partition_number=$(parted ${found_device} print | grep -o -e '^ [0-9]*' | awk '{print $1}' | tail -n 1)
+    local new_partition_device=$(lsblk -r -n -o PARTN,NAME ${found_device} | awk -v partition_number="${last_partition_number}" '$1 == partition_number {print $2}')
+
+    mkfs.ext4 -F /dev/${new_partition_device}
+    if [ $? -ne 0 ]; then
+        echo "Could not initialize filesystem on new partition !"
+        exit 1
+    fi
+    
+    local new_partition_uuid=$(lsblk -r -n -o PARTN,UUID ${found_device} | awk -v partition_number="${last_partition_number}" '$1 == partition_number {print $2}')
+
+    if [ -z "${new_partition_uuid}" ]; then
+        echo "Could not find partition with number '${last_partition_number}' !"
+        exit 1
+    fi
+
+    umount -f /data
+    rm -rf /data
+    mkdir -p /data
+
+    uci add fstab mount
+    uci set fstab.@mount[-1].target='/data'
+    uci set fstab.@mount[-1].uuid=${new_partition_uuid}
+    uci set fstab.@mount[-1].enabled='1'
+    uci commit fstab
+
+    reload_config
+}
+
+main
\ No newline at end of file
diff --git a/packages.txt b/packages.txt
index 9fe1252..b93ee41 100644
--- a/packages.txt
+++ b/packages.txt
@@ -1,3 +1,7 @@
 luci 
 openssh-server
-openssh-sftp-server
\ No newline at end of file
+openssh-sftp-server
+parted
+lsblk
+e2fsprogs
+block-mount
\ No newline at end of file