From ddd28e45d507665ffd89b35e8c759b6add7686a6 Mon Sep 17 00:00:00 2001
From: Andrew Cady <d@jerkface.net>
Date: Wed, 19 Jun 2019 18:26:54 -0400
Subject: add some commands to the live system

---
 src/samizdat-daily-snapshot-root | 55 ++++++++++++++++++++++++++++++++++++++++
 src/samizdat-diff-root           | 43 +++++++++++++++++++++++++++++++
 2 files changed, 98 insertions(+)
 create mode 100755 src/samizdat-daily-snapshot-root
 create mode 100755 src/samizdat-diff-root

(limited to 'src')

diff --git a/src/samizdat-daily-snapshot-root b/src/samizdat-daily-snapshot-root
new file mode 100755
index 0000000..c57524c
--- /dev/null
+++ b/src/samizdat-daily-snapshot-root
@@ -0,0 +1,55 @@
+#/bin/sh
+[ "$(id -u)" = 0 ] || exec sudo "$0" "$@" || exit
+
+is_subvol()
+{
+    btrfs subvolume show "$1" >/dev/null 2>&1
+}
+
+btrfs_subvolumes()
+{
+    btrfs subvolume list -a -t "${1:-/}" | awk '{print $4}' | sed -Ene 's?^(<FS_TREE>/)\?root/?/?p'
+}
+
+snapit()
+{
+    local dev mnt target
+
+    mnt=$(mktemp -d /tmp/mnt.XXXXXX) || return
+    src=$mnt/$1/
+    target=$mnt/${2:-daily/}${1%/}~$(date -I)
+    dev=$(btrfs fi sh / | sed -ne 's/.* path //p' | tail -n1) || return
+
+    mount "$dev" -o subvol=/ "$mnt"
+    if [ -e "$target" ]
+    then
+      :
+    else
+      mkdir -p "$(dirname "$target")"
+      btrfs subvolume snapshot -r "$src" "$target"
+    fi
+    umount "$mnt"
+    rmdir "$mnt"
+}
+
+do_not_snap()
+{
+  case "${1#/root/}" in
+    /var/cache/apt/archives|/home/*/.cache|/home/*/src/fsmgr/_build|/home/*/.stack|/home/*/.rustup)
+      true
+    ;;
+    *)
+      false
+    ;;
+  esac
+}
+
+snapit /root
+
+btrfs_subvolumes | while read f
+do
+    if is_subvol "$f"
+    then
+        do_not_snap "$f" || snapit /root/"${f#/}"
+    fi
+done
diff --git a/src/samizdat-diff-root b/src/samizdat-diff-root
new file mode 100755
index 0000000..ea9bb85
--- /dev/null
+++ b/src/samizdat-diff-root
@@ -0,0 +1,43 @@
+#!/bin/sh
+mp=/mnt/root.tmp
+fs=/
+
+excludes='--exclude /var/log/ --exclude /tmp/'
+
+devs()
+{
+  btrfs fi sh "$fs"  | sed -ne 's?^[ \t]*devid[ \t].*/dev?/dev?p'
+}
+
+[ $(id -u) = 0 ] || exec sudo "$0" "$@" || exit
+
+if ! [ -e "$mp" ] || ! mountpoint -q "$mp"
+then
+  mkdir -p "$mp"
+  dev=$(devs | tail -n1) || exit
+  mount -t btrfs "$dev" -o subvol=/ "$mp" || exit
+fi
+
+case $# in
+  0) run()
+     {
+       rsync -xani $excludes "$mp"/root/ "$mp"/root~orig/
+     }
+     ;;
+  *) run()
+     {
+       for f
+       do
+         diff "$mp"/root/"$f" "$mp"/root~orig/"$f"
+       done
+     }
+     ;;
+esac
+if [ -t 0 ]
+then
+  run "$@" | less
+else
+  run "$@"
+fi
+
+umount "$mp"
-- 
cgit v1.2.3