bundles/samba: add code to show up as time machine backup target

bundles/samba/files/smb.conf

@@ -13,6 +13,13 @@ map to guest = bad user
 load printers = no
 usershare allow guests = yes
 allow insecure wide links = yes
+min protocol = SMB2
+% if timemachine:
+vfs objects = fruit
+fruit:aapl = yes
+fruit:copyfile = yes
+fruit:model = MacSamba
+% endif
 % for name, opts in sorted(node.metadata.get('samba/shares', {}).items()):
 
 [${name}]
@@ -37,3 +44,24 @@ follow symlinks = yes
 wide links = yes
 %  endif
 % endfor
+% for name in sorted(timemachine):
+
+[timemachine-${name}]
+comment = Time Machine backup for ${name}
+available = yes
+browseable = yes
+guest ok = no
+read only = false
+valid users = timemachine-${name}
+path = /srv/timemachine/${name}
+durable handles = yes
+vfs objects = catia fruit streams_xattr
+
+fruit:delete_empty_adfiles = yes
+fruit:metadata = stream
+fruit:posix_rename = yes
+fruit:time machine = yes
+fruit:time machine max size = 750G
+fruit:veto_appledouble = no
+fruit:wipe_intentionally_left_blank_rfork = yes
+% endfor

bundles/samba/files/timemachine.service

@@ -0,0 +1,21 @@
+<?xml version="1.0" standalone='no'?>
+<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
+<service-group>
+    <name replace-wildcards="yes">%h</name>
+    <service>
+        <type>_smb._tcp</type>
+        <port>445</port>
+    </service>
+    <service>
+        <type>_device-info._tcp</type>
+        <port>0</port>
+        <txt-record>model=RackMac1,2</txt-record>
+    </service>
+    <service>
+        <type>_adisk._tcp</type>
+% for idx, share_name in enumerate(sorted(shares)):
+        <txt-record>dk${idx}=adVN=timemachine-${share_name},adVF=0x82</txt-record>
+% endfor
+        <txt-record>sys=waMa=0,adVF=0x100</txt-record>
+    </service>
+</service-group>