babeld: Backward compatibility with old config files

This allows to use the old syntax "config interface foo" for specifying an
interface.  The new syntax ("option ifname foo") takes precedence.

Also, old option names for the "general" section are translated
accordingly.  Exceptions are:

- 'hello_interval' and 'wired_hello_interval', which are now interface-specific;
- 'conf_file', since /etc/babeld.conf is now always used;

which are simply ignored.

Beware, the syntax for the 'diversity' option is not backward compatible.

diff --git a/babeld/files/babeld.init b/babeld/files/babeld.init
index d6a6f1ea264fba31ea4814e5f64105fef3794656..180fc7e04f8f1082d7930221a16dad7f8fb22c9d 100755 (executable)
--- a/babeld/files/babeld.init
+++ b/babeld/files/babeld.init
@@ -10,6 +10,10 @@ OTHERCONFIGFILE="/etc/babeld.conf"
 EXTRA_COMMANDS="status"
 EXTRA_HELP="        status Dump Babel's table to the log file."
 
+# Options to ignore for the global section (old options that are translated
+# for backward compatibility with old configuration files)
+ignored_options="carrier_sense assume_wireless no_split_horizon random_router_id multicast_address port hello_interval wired_hello_interval smoothing_half_time duplication_priority local_server conf_file"
+
 # Append a line to the configuration file
 cfg_append() {
         local value="$1"
@@ -56,6 +60,56 @@ append_parm() {
        append buffer "$switch $_loctmp"
 }
 
+
+# Provides backward compatibility for old option names in the global section.
+translate_option() {
+       local section="$1"
+       local old_option="$2"
+       local new_option="$3"
+       local _value
+       config_get _value "$section" "$old_option"
+       [ -z "$_value" ] && return
+       cfg_append "${new_option//_/-} $_value"
+}
+
+translate_bool() {
+       local section="$1"
+       local old_option="$2"
+       local new_option="$3"
+       local _bool
+       local _value
+       config_get_bool _bool "$section" "$old_option" 0
+       [ "$_bool" -eq 0 ] && return
+       cfg_append "${new_option//_/-} true"
+}
+
+# Adds a new interface section for setting default interface options.
+add_default_option() {
+       local option="$1"
+       local value="$2"
+       cfg_append "default ${option//_/-} $value"
+}
+
+# Global 'hello_interval' and 'wired_hello_interval' options are ignored,
+# because they have no direct equivalent: you should use
+# interface-specific settings.
+parse_old_global_options() {
+       local section="$1"
+       translate_bool   "$section" 'carrier_sense'     'link_detect'
+       translate_bool   "$section" 'random_router_id'  'random_id'
+       translate_option "$section" 'multicast_address' 'protocol_group'
+       translate_option "$section" 'port'              'protocol_port'
+       translate_option "$section" 'local_server'      'local_port'
+       translate_option "$section" 'smoothing_half_time'       'smoothing_half_life'
+       translate_option "$section" 'duplication_priority'      'allow_duplicates'
+       # These two global options are turned into default interface options.
+       local _bool
+       config_get_bool _bool "$section" 'assume_wireless' 0
+       [ "$_bool" -eq 1 ] && add_default_option "wired" "false"
+       config_get_bool _bool "$section" 'no_split_horizon' 0
+       [ "$_bool" -eq 1 ] && add_default_option "split_horizon" "false"
+}
+
 babel_filter() {
        local cfg="$1"
        local _loctmp
@@ -98,12 +152,17 @@ babel_config_cb() {
                option_cb() {
                        local option="$1"
                        local value="$2"
+                       # Ignore old options
+                       list_contains ignored_options "$option" && return
                        cfg_append "${option//_/-} $value"
                }
        ;;
        "interface")
                local _ifname
                config_get _ifname "$section" 'ifname'
+               # Backward compatibility: try to use the section name
+               # if no "option ifname" was used.
+               [ -z "$_ifname" -a "${section:0:3}" != "cfg" ] && _ifname="$section"
                # Try to resolve the logical interface name
                unset interface
                network_get_device interface "$_ifname" || interface="$_ifname"
@@ -150,6 +209,8 @@ start() {
        # know their name in advance.
        config_cb() { babel_config_cb "$@"; }
        config_load babeld
+       # Backward compatibility
+       config_foreach parse_old_global_options general
        # Parse filters separately, since we know which options we expect
        config_foreach babel_filter filter
        # Using multiple config files is supported since babeld 1.5.1