1 files changed, 280 insertions, 196 deletions

diff --git a/meta/recipes-core/systemd/systemd-systemctl/systemctl b/meta/recipes-core/systemd/systemd-systemctl/systemctl
index 2bc6489617..d7d4e0d29a 100755
--- a/meta/recipes-core/systemd/systemd-systemctl/systemctl
+++ b/meta/recipes-core/systemd/systemd-systemctl/systemctl
@@ -1,196 +1,280 @@
-#!/bin/sh
-echo "Started $0 $*"
-
-ROOT=
-
-# parse command line params
-action=
-while [ $# != 0 ]; do
-        opt="$1"
-
-        case "$opt" in
-                enable)
-                        shift
-
-                        action="$opt"
-                        services="$1"
-                        cmd_args="1"
-                        shift
-                        ;;
-                disable)
-                        shift
-
-                        action="$opt"
-                        services="$1"
-                        cmd_args="1"
-                        shift
-                        ;;
-                mask)
-                        shift
-
-                        action="$opt"
-                        services="$1"
-                        cmd_args="1"
-                        shift
-                        ;;
-                preset)
-                        shift
-
-                        action="$opt"
-                        services="$1"
-                        cmd_args="1"
-                        shift
-                        ;;
-                --root=*)
-                        ROOT=${opt##--root=}
-                        cmd_args="0"
-                        shift
-                        ;;
-                *)
-                        if [ "$cmd_args" = "1" ]; then
-                                services="$services $opt" 
-                                shift
-                        else
-                                echo "'$opt' is an unkown option; exiting with error"
-                                exit 1
-                        fi
-                        ;;
-        esac
-done
-if [ "$action" = "preset" -a "$service_file" = "" ]; then
-        services=$(for f in `find $ROOT/etc/systemd/system $ROOT/lib/systemd/system $ROOT/usr/lib/systemd/system -type f 2>1`; do basename $f; done)
-        services="$services $opt"
-        presetall=1
-fi
-
-for service in $services; do
-        if [ "$presetall" = "1" ]; then
-                action="preset"
-        fi
-        if [ "$action" = "mask" ]; then
-                if [ ! -d $ROOT/etc/systemd/system/ ]; then
-                        mkdir -p $ROOT/etc/systemd/system/
-                fi
-                cmd="ln -s /dev/null $ROOT/etc/systemd/system/$service"
-                echo "$cmd"
-                $cmd
-                exit 0
-        fi
-
-        service_base_file=`echo $service | sed 's/\(@\).*\(\.[^.]\+\)/\1\2/'`
-        if [ -z `echo $service | sed '/@/p;d'` ]; then
-                echo "Try to find location of $service..."
-                service_template=false
-        else
-                echo "Try to find location of template $service_base_file of instance $service..."
-                service_template=true
-                instance_specified=`echo $service | sed 's/^.\+@\(.*\)\.[^.]\+/\1/'`
-        fi
-
-        # find service file
-        for p in $ROOT/etc/systemd/system \
-                 $ROOT/lib/systemd/system \
-                 $ROOT/usr/lib/systemd/system; do
-                if [ -e $p/$service_base_file ]; then
-                        service_file=$p/$service_base_file
-                        service_file=${service_file##$ROOT}
-                fi
-        done
-        if [ -z "$service_file" ]; then
-                echo "'$service_base_file' couldn't be found; exiting with error"
-                exit 1
-        fi
-        echo "Found $service in $service_file"
-
-        # If any new unit types are added to systemd they should be added
-        # to this regular expression.
-        unit_types_re='\.\(service\|socket\|device\|mount\|automount\|swap\|target\|target\.wants\|path\|timer\|snapshot\)\s*$'
-        if [ "$action" = "preset" ]; then
-                action=`egrep -sh  $service $ROOT/etc/systemd/user-preset/*.preset | cut -f1 -d' '`
-                if [ -z "$action" ]; then
-                        globalpreset=`egrep -sh  '\*'  $ROOT/etc/systemd/user-preset/*.preset | cut -f1 -d' '`
-                        if [ -n "$globalpreset" ]; then
-                                action="$globalpreset"
-                        else
-                                action="enable"
-                        fi
-                fi
-        fi
-        # create the required symbolic links
-        wanted_by=$(sed '/^WantedBy[[:space:]]*=/s,[^=]*=,,p;d' "$ROOT/$service_file" \
-                        | tr ',' '\n' \
-                        | grep "$unit_types_re")
-
-        required_by=$(sed '/^RequiredBy[[:space:]]*=/s,[^=]*=,,p;d' "$ROOT/$service_file" \
-                        | tr ',' '\n' \
-                        | grep "$unit_types_re")
-
-        for dependency in WantedBy RequiredBy; do
-                if [ "$dependency" = "WantedBy" ]; then
-                        suffix="wants"
-                        dependency_list="$wanted_by"
-                elif [ "$dependency" = "RequiredBy" ]; then
-                        suffix="requires"
-                        dependency_list="$required_by"
-                fi
-                for r in $dependency_list; do
-                        echo "$dependency=$r found in $service"
-                        if [ -n "$instance_specified" ]; then
-                                # substitute wildcards in the dependency
-                                r=`echo $r | sed "s/%i/$instance_specified/g"`
-                        fi
-
-                        if [ "$action" = "enable" ]; then
-                                enable_service=$service
-                                if [ "$service_template" = true -a -z "$instance_specified" ]; then
-                                        default_instance=$(sed '/^DefaultInstance[[:space:]]*=/s,[^=]*=,,p;d' "$ROOT/$service_file")
-                                        if [ -z $default_instance ]; then
-                                                echo "Template unit without instance or DefaultInstance directive, nothing to enable"
-                                                continue
-                                        else
-                                                echo "Found DefaultInstance $default_instance, enabling it"
-                                                enable_service=$(echo $service | sed "s/@/@$(echo $default_instance | sed 's/\\/\\\\/g')/")
-                                        fi
-                                fi
-                                mkdir -p $ROOT/etc/systemd/system/$r.$suffix
-                                ln -s $service_file $ROOT/etc/systemd/system/$r.$suffix/$enable_service
-                                echo "Enabled $enable_service for $r."
-                        else
-                                if [ "$service_template" = true -a -z "$instance_specified" ]; then
-                                        disable_service="$ROOT/etc/systemd/system/$r.$suffix/`echo $service | sed 's/@/@*/'`"
-                                else
-                                        disable_service="$ROOT/etc/systemd/system/$r.$suffix/$service"
-                                fi
-                                rm -f $disable_service
-                                [ -d $ROOT/etc/systemd/system/$r.$suffix ] && rmdir --ignore-fail-on-non-empty -p $ROOT/etc/systemd/system/$r.$suffix
-                                echo "Disabled ${disable_service##$ROOT/etc/systemd/system/$r.$suffix/} for $r."
-                        fi
-                done
-        done
-
-        # create the required symbolic 'Alias' links
-        alias=$(sed '/^Alias[[:space:]]*=/s,[^=]*=,,p;d' "$ROOT/$service_file" \
-                        | tr ',' '\n' \
-                        | grep "$unit_types_re")
-
-        for r in $alias; do
-                if [ "$action" = "enable" ]; then
-                        mkdir -p $ROOT/etc/systemd/system
-                        ln -s $service_file $ROOT/etc/systemd/system/$r
-                        echo "Enabled $service for $alias."
-                else
-                        rm -f $ROOT/etc/systemd/system/$r
-                        echo "Disabled $service for $alias."
-                fi
-        done
-
-        # call us for the other required scripts
-        also=$(sed '/^Also[[:space:]]*=/s,[^=]*=,,p;d' "$ROOT/$service_file" \
-                   | tr ',' '\n')
-        for a in $also; do
-                echo "Also=$a found in $service"
-                if [ "$action" = "enable" ]; then
-                        $0 --root=$ROOT enable $a
-                fi
-        done
-done
+#!/usr/bin/env python3
+"""systemctl: subset of systemctl used for image construction
+
+Mask/preset systemd units
+"""
+
+import argparse
+import fnmatch
+import os
+import re
+import sys
+
+from collections import namedtuple
+from pathlib import Path
+
+version = 1.0
+
+ROOT = Path("/")
+SYSCONFDIR = Path("etc")
+BASE_LIBDIR = Path("lib")
+LIBDIR = Path("usr", "lib")
+
+
+class SystemdFile():
+    """Class representing a single systemd configuration file"""
+    def __init__(self, root, path):
+        self.sections = dict()
+        self._parse(root, path)
+
+    def _parse(self, root, path):
+        """Parse a systemd syntax configuration file
+
+        Args:
+            path: A pathlib.Path object pointing to the file
+
+        """
+        skip_re = re.compile(r"^\s*([#;]|$)")
+        section_re = re.compile(r"^\s*\[(?P<section>.*)\]")
+        kv_re = re.compile(r"^\s*(?P<key>[^\s]+)\s*=\s*(?P<value>.*)")
+        section = None
+
+        if path.is_symlink():
+            try:
+                path.resolve()
+            except FileNotFoundError:
+                # broken symlink, try relative to root
+                path = root / Path(os.readlink(str(path))).relative_to(ROOT)
+
+        with path.open() as f:
+            for line in f:
+                if skip_re.match(line):
+                    continue
+
+                line = line.rstrip("\n")
+                m = section_re.match(line)
+                if m:
+                    section = dict()
+                    self.sections[m.group('section')] = section
+                    continue
+
+                while line.endswith("\\"):
+                    line += f.readline().rstrip("\n")
+
+                m = kv_re.match(line)
+                k = m.group('key')
+                v = m.group('value')
+                if k not in section:
+                    section[k] = list()
+                section[k].extend(v.split())
+
+    def get(self, section, prop):
+        """Get a property from section
+
+        Args:
+            section: Section to retrieve property from
+            prop: Property to retrieve
+
+        Returns:
+            List representing all properties of type prop in section.
+
+        Raises:
+            KeyError: if ``section`` or ``prop`` not found
+        """
+        return self.sections[section][prop]
+
+
+class Presets():
+    """Class representing all systemd presets"""
+    def __init__(self, scope, root):
+        self.directives = list()
+        self._collect_presets(scope, root)
+
+    def _parse_presets(self, presets):
+        """Parse presets out of a set of preset files"""
+        skip_re = re.compile(r"^\s*([#;]|$)")
+        directive_re = re.compile(r"^\s*(?P<action>enable|disable)\s+(?P<unit_name>(.+))")
+
+        Directive = namedtuple("Directive", "action unit_name")
+        for preset in presets:
+            with preset.open() as f:
+                for line in f:
+                    m = directive_re.match(line)
+                    if m:
+                        directive = Directive(action=m.group('action'),
+                                              unit_name=m.group('unit_name'))
+                        self.directives.append(directive)
+                    elif skip_re.match(line):
+                        pass
+                    else:
+                        sys.exit("Unparsed preset line in {}".format(preset))
+
+    def _collect_presets(self, scope, root):
+        """Collect list of preset files"""
+        locations = [SYSCONFDIR / "systemd"]
+        # Handle the usrmerge case by ignoring /lib when it's a symlink
+        if not BASE_LIBDIR.is_symlink():
+            locations.append(BASE_LIBDIR / "systemd")
+        locations.append(LIBDIR / "systemd")
+
+        presets = dict()
+        for location in locations:
+            paths = (root / location / scope).glob("*.preset")
+            for path in paths:
+                # earlier names override later ones
+                if path.name not in presets:
+                    presets[path.name] = path
+
+        self._parse_presets([v for k, v in sorted(presets.items())])
+
+    def state(self, unit_name):
+        """Return state of preset for unit_name
+
+        Args:
+            presets: set of presets
+            unit_name: name of the unit
+
+        Returns:
+            None: no matching preset
+            `enable`: unit_name is enabled
+            `disable`: unit_name is disabled
+        """
+        for directive in self.directives:
+            if fnmatch.fnmatch(unit_name, directive.unit_name):
+                return directive.action
+
+        return None
+
+
+def collect_services(root):
+    """Collect list of service files"""
+    locations = [SYSCONFDIR / "systemd"]
+    # Handle the usrmerge case by ignoring /lib when it's a symlink
+    if not BASE_LIBDIR.is_symlink():
+        locations.append(BASE_LIBDIR / "systemd")
+    locations.append(LIBDIR / "systemd")
+
+    services = dict()
+    for location in locations:
+        paths = (root / location / "system").glob("*")
+        for path in paths:
+            if path.is_dir():
+                continue
+            # implement earlier names override later ones
+            if path.name not in services:
+                services[path.name] = path
+
+    return services
+
+
+def add_link(path, target):
+    try:
+        path.parent.mkdir(parents=True)
+    except FileExistsError:
+        pass
+    if not path.is_symlink():
+        print("ln -s {} {}".format(target, path))
+        path.symlink_to(target)
+
+
+def process_deps(root, config, service, location, prop, dirstem):
+    systemdir = SYSCONFDIR / "systemd" / "system"
+
+    target = ROOT / location.relative_to(root)
+    try:
+        for dependent in config.get('Install', prop):
+            wants = root / systemdir / "{}.{}".format(dependent, dirstem) / service
+            add_link(wants, target)
+
+    except KeyError:
+        pass
+
+
+def enable(root, service, location, services):
+    if location.is_symlink():
+        # ignore aliases
+        return
+
+    config = SystemdFile(root, location)
+    template = re.match(r"[^@]+@(?P<instance>[^\.]*)\.", service)
+    if template:
+        instance = template.group('instance')
+        if not instance:
+            try:
+                instance = config.get('Install', 'DefaultInstance')[0]
+                service = service.replace("@.", "@{}.".format(instance))
+            except KeyError:
+                pass
+        if instance is None:
+            return
+    else:
+        instance = None
+
+    process_deps(root, config, service, location, 'WantedBy', 'wants')
+    process_deps(root, config, service, location, 'RequiredBy', 'requires')
+
+    try:
+        for also in config.get('Install', 'Also'):
+            enable(root, also, services[also], services)
+
+    except KeyError:
+        pass
+
+    systemdir = root / SYSCONFDIR / "systemd" / "system"
+    target = ROOT / location.relative_to(root)
+    try:
+        for dest in config.get('Install', 'Alias'):
+            alias = systemdir / dest
+            add_link(alias, target)
+
+    except KeyError:
+        pass
+
+
+def preset_all(root):
+    presets = Presets('system-preset', root)
+    services = collect_services(root)
+
+    for service, location in services.items():
+        state = presets.state(service)
+
+        if state == "enable" or state is None:
+            enable(root, service, location, services)
+
+
+def mask(root, *services):
+    systemdir = root / SYSCONFDIR / "systemd" / "system"
+    for service in services:
+        add_link(systemdir / service, "/dev/null")
+
+
+def main():
+    if sys.version_info < (3, 4, 0):
+        sys.exit("Python 3.4 or greater is required")
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument('command', nargs=1, choices=['mask', 'preset-all'])
+    parser.add_argument('service', nargs=argparse.REMAINDER)
+    parser.add_argument('--root')
+    parser.add_argument('--preset-mode',
+                        choices=['full', 'enable-only', 'disable-only'],
+                        default='full')
+
+    args = parser.parse_args()
+
+    root = Path(args.root) if args.root else ROOT
+    command = args.command[0]
+    if command == "mask":
+        mask(root, *args.service)
+    elif command == "preset-all":
+        if len(args.service) != 0:
+            sys.exit("Too many arguments.")
+        if args.preset_mode != "enable-only":
+            sys.exit("Only enable-only is supported as preset-mode.")
+        preset_all(root)
+    else:
+        raise RuntimeError()
+
+
+if __name__ == '__main__':
+    main()