2 files changed, 355 insertions, 0 deletions

diff --git a/meta-oe/recipes-devtools/systemd/nativesdk-systemd-systemctl.bb b/meta-oe/recipes-devtools/systemd/nativesdk-systemd-systemctl.bb
new file mode 100644
index 0000000000..f7160f508b
--- /dev/null
+++ b/meta-oe/recipes-devtools/systemd/nativesdk-systemd-systemctl.bb
@@ -0,0 +1,15 @@
+SUMMARY = "Wrapper for enabling systemd services"
+
+LICENSE = "MIT"
+LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
+
+inherit nativesdk
+
+SRC_URI = "file://systemctl"
+
+S = "${WORKDIR}"
+
+do_install() {
+        install -d ${D}${bindir}
+        install -m 0755 ${WORKDIR}/systemctl ${D}${bindir}
+}
diff --git a/meta-oe/recipes-devtools/systemd/systemd-systemctl/systemctl b/meta-oe/recipes-devtools/systemd/systemd-systemctl/systemctl
new file mode 100755
index 0000000000..07d24fd175
--- /dev/null
+++ b/meta-oe/recipes-devtools/systemd/systemd-systemctl/systemctl
@@ -0,0 +1,340 @@
+#!/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")
+
+locations = list()
+
+
+class SystemdFile():
+    """Class representing a single systemd configuration file"""
+    def __init__(self, root, path):
+        self.sections = dict()
+        self._parse(root, path)
+        dirname = os.path.basename(path.name) + ".d"
+        for location in locations:
+            for path2 in sorted((root / location / "system" / dirname).glob("*.conf")):
+                self._parse(root, path2)
+
+    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.strip()
+                m = section_re.match(line)
+                if m:
+                    if m.group('section') not in self.sections:
+                        section = dict()
+                        self.sections[m.group('section')] = section
+                    else:
+                        section = self.sections[m.group('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"""
+        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 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)
+
+
+class SystemdUnitNotFoundError(Exception):
+    def __init__(self, path, unit):
+        self.path = path
+        self.unit = unit
+
+
+class SystemdUnit():
+    def __init__(self, root, unit):
+        self.root = root
+        self.unit = unit
+        self.config = None
+
+    def _path_for_unit(self, unit):
+        for location in locations:
+            path = self.root / location / "system" / unit
+            if path.exists() or path.is_symlink():
+                return path
+
+        raise SystemdUnitNotFoundError(self.root, unit)
+
+    def _process_deps(self, config, service, location, prop, dirstem):
+        systemdir = self.root / SYSCONFDIR / "systemd" / "system"
+
+        target = ROOT / location.relative_to(self.root)
+        try:
+            for dependent in config.get('Install', prop):
+                wants = systemdir / "{}.{}".format(dependent, dirstem) / service
+                add_link(wants, target)
+
+        except KeyError:
+            pass
+
+    def enable(self, caller_unit=None):
+        # if we're enabling an instance, first extract the actual instance
+        # then figure out what the template unit is
+        template = re.match(r"[^@]+@(?P<instance>[^\.]*)\.", self.unit)
+        if template:
+            instance = template.group('instance')
+            unit = re.sub(r"@[^\.]*\.", "@.", self.unit, 1)
+        else:
+            instance = None
+            unit = self.unit
+
+        path = self._path_for_unit(unit)
+
+        if path.is_symlink():
+            # ignore aliases
+            return
+
+        config = SystemdFile(self.root, path)
+        if instance == "":
+            try:
+                default_instance = config.get('Install', 'DefaultInstance')[0]
+            except KeyError:
+                # no default instance, so nothing to enable
+                return
+
+            service = self.unit.replace("@.",
+                                        "@{}.".format(default_instance))
+        else:
+            service = self.unit
+
+        self._process_deps(config, service, path, 'WantedBy', 'wants')
+        self._process_deps(config, service, path, 'RequiredBy', 'requires')
+
+        try:
+            for also in config.get('Install', 'Also'):
+                try:
+                    if caller_unit != also:
+                        SystemdUnit(self.root, also).enable(unit)
+                except SystemdUnitNotFoundError as e:
+                    sys.exit("Error: Systemctl also enable issue with  %s (%s)" % (service, e.unit))
+
+        except KeyError:
+            pass
+
+        systemdir = self.root / SYSCONFDIR / "systemd" / "system"
+        target = ROOT / path.relative_to(self.root)
+        try:
+            for dest in config.get('Install', 'Alias'):
+                alias = systemdir / dest
+                add_link(alias, target)
+
+        except KeyError:
+            pass
+
+    def mask(self):
+        systemdir = self.root / SYSCONFDIR / "systemd" / "system"
+        add_link(systemdir / self.unit, "/dev/null")
+
+
+def collect_services(root):
+    """Collect list of service files"""
+    services = set()
+    for location in locations:
+        paths = (root / location / "system").glob("*")
+        for path in paths:
+            if path.is_dir():
+                continue
+            services.add(path.name)
+
+    return services
+
+
+def preset_all(root):
+    presets = Presets('system-preset', root)
+    services = collect_services(root)
+
+    for service in services:
+        state = presets.state(service)
+
+        if state == "enable" or state is None:
+            try:
+                SystemdUnit(root, service).enable()
+            except SystemdUnitNotFoundError:
+                sys.exit("Error: Systemctl preset_all issue in %s" % service)
+
+    # If we populate the systemd links we also create /etc/machine-id, which
+    # allows systemd to boot with the filesystem read-only before generating
+    # a real value and then committing it back.
+    #
+    # For the stateless configuration, where /etc is generated at runtime
+    # (for example on a tmpfs), this script shouldn't run at all and we
+    # allow systemd to completely populate /etc.
+    (root / SYSCONFDIR / "machine-id").touch()
+
+
+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='?', choices=['enable', '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
+
+    locations.append(SYSCONFDIR / "systemd")
+    # Handle the usrmerge case by ignoring /lib when it's a symlink
+    if not (root / BASE_LIBDIR).is_symlink():
+        locations.append(BASE_LIBDIR / "systemd")
+    locations.append(LIBDIR / "systemd")
+
+    command = args.command
+    if not command:
+        parser.print_help()
+        return 0
+
+    if command == "mask":
+        for service in args.service:
+            try:
+                SystemdUnit(root, service).mask()
+            except SystemdUnitNotFoundError as e:
+                sys.exit("Error: Systemctl main mask issue in %s (%s)" % (service, e.unit))
+    elif command == "enable":
+        for service in args.service:
+            try:
+                SystemdUnit(root, service).enable()
+            except SystemdUnitNotFoundError as e:
+                sys.exit("Error: Systemctl main enable issue in %s (%s)" % (service, e.unit))
+    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()