diff mbox series

[v2,3/3] systemd: Build the systemctl executable

Message ID 20250204105315.84079-3-uvv.mail@gmail.com
State New
Headers show
Series [v2,1/3] bitbake.conf: Add conditional host tool getent | expand

Commit Message

Vyacheslav Yurkov Feb. 4, 2025, 10:53 a.m. UTC
From: Vyacheslav Yurkov <uvv.mail@gmail.com>

Instead of the python re-implementation build the actual systemctl from
the systemd source tree. The python script was used when systemd didn't
provide an option to build individual executables. It is possible in the
meantime, so instead of always adapting the script when there's a new
functionality, we simply use upstream implementation.

Signed-off-by: Vyacheslav Yurkov <uvv.mail@gmail.com>
---
 .../systemd/systemd-systemctl-native.bb       |  20 +-
 ...-meson-add-install-tag-for-systemctl.patch |  25 ++
 .../systemd/systemd-systemctl/systemctl       | 366 ------------------
 3 files changed, 33 insertions(+), 378 deletions(-)
 create mode 100644 meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch
 delete mode 100755 meta/recipes-core/systemd/systemd-systemctl/systemctl

Comments

patchtest@automation.yoctoproject.org Feb. 4, 2025, 11:02 a.m. UTC | #1
Thank you for your submission. Patchtest identified one
or more issues with the patch. Please see the log below for
more information:

---
Testing patch /home/patchtest/share/mboxes/v2-3-3-systemd-Build-the-systemctl-executable.patch

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---

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you!
Mikko Rapeli Feb. 4, 2025, 1:18 p.m. UTC | #2
Hi,

On Tue, Feb 04, 2025 at 11:53:15AM +0100, Vyacheslav Yurkov via lists.openembedded.org wrote:
> From: Vyacheslav Yurkov <uvv.mail@gmail.com>
> 
> Instead of the python re-implementation build the actual systemctl from
> the systemd source tree. The python script was used when systemd didn't
> provide an option to build individual executables. It is possible in the
> meantime, so instead of always adapting the script when there's a new
> functionality, we simply use upstream implementation.

Good reason, no objections!

> Signed-off-by: Vyacheslav Yurkov <uvv.mail@gmail.com>
> ---
>  .../systemd/systemd-systemctl-native.bb       |  20 +-
>  ...-meson-add-install-tag-for-systemctl.patch |  25 ++
>  .../systemd/systemd-systemctl/systemctl       | 366 ------------------
>  3 files changed, 33 insertions(+), 378 deletions(-)
>  create mode 100644 meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch
>  delete mode 100755 meta/recipes-core/systemd/systemd-systemctl/systemctl
> 
> diff --git a/meta/recipes-core/systemd/systemd-systemctl-native.bb b/meta/recipes-core/systemd/systemd-systemctl-native.bb
> index ffa024caef..57bb1ab830 100644
> --- a/meta/recipes-core/systemd/systemd-systemctl-native.bb
> +++ b/meta/recipes-core/systemd/systemd-systemctl-native.bb
> @@ -1,17 +1,13 @@
> -SUMMARY = "Wrapper for enabling systemd services"
> +SUMMARY = "Systemctl executable from systemd"
>  
> -LICENSE = "MIT"
> -LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
> +require systemd.inc
>  
> +DEPENDS = "gperf-native libcap-native util-linux-native python3-jinja2-native"
>  
> -inherit native
> +inherit pkgconfig meson native
>  
> -SRC_URI = "file://systemctl"
> +SRC_URI = "file://0001-meson-add-install-tag-for-systemctl.patch"

Hmm, doesn't this overwrite SRC_URI from systemd.inc?

SRC_URI += "file://...patch" would amend the patch file.

> -S = "${WORKDIR}/sources"
> -UNPACKDIR = "${S}"
> -
> -do_install() {
> -	install -d ${D}${bindir}
> -	install -m 0755 ${S}/systemctl ${D}${bindir}
> -}
> +MESON_TARGET = "systemctl:executable"
> +MESON_INSTALL_TAGS = "systemctl"
> +EXTRA_OEMESON:append = " -Dlink-systemctl-shared=false"

I wonder why this tag support is needed since MESON_TARGET already
compiles only the correct executable with static linking. Is it there
just to let meson handle the install step of a single systemctl
executable?

Or does it install more files, like config files too?

I'm comparing this to a draft systemd-boot-native recipe for ukify
which I had and which sets the build target but installs manually:

MESON_TARGET = "ukify"

EXTRA_OEMESON += "-Dnobody-user=nobody \
    -Dnobody-group=nogroup \
    -Drootlibdir=${rootlibdir} \
    -Drootprefix=${rootprefix} \
    -Ddefault-locale=C \
    -Dmode=release \
    -Dsystem-alloc-uid-min=101 \
    -Dsystem-uid-max=999 \
    -Dsystem-alloc-gid-min=101 \
    -Dsystem-gid-max=999 \
"

do_install() {
    install -d ${D}${bindir}/
    install -m 0755 ${S}/src/ukify/ukify.py ${D}${bindir}/ukify
}

So the custom do_install() step could be avoided if systemd meson config
would have "install_tag" for ukify too?

Current systemd-boot-native recipe installs/copies the unmodified ukify.py
from source tree and uses that in native. It doesn't run meson build for it
and thus things like version details are incorrect. Also some additional tools
like systemd-measure, systemd-sbsign etc are not compiled so some usecases may
not be supported atm. If those would also include the install tags, then they
could be compiled and installed too, I presume.

> diff --git a/meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch b/meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch
> new file mode 100644
> index 0000000000..a9b3e62708
> --- /dev/null
> +++ b/meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch
> @@ -0,0 +1,25 @@
> +From fbf1ae3b7bd074a8d3bfb741f54b8539123399f1 Mon Sep 17 00:00:00 2001
> +From: Vyacheslav Yurkov <uvv.mail@gmail.com>
> +Date: Sun, 2 Feb 2025 10:13:38 +0100
> +Subject: [PATCH] meson: add install tag for systemctl
> +
> +Upstream-Status: Backport
> +[https://github.com/systemd/systemd/commit/b1e5a7aa3f1e552c56d5adbeed6ff67d88d1e103]

Thanks for getting this upstreamed!

Cheers,

-Mikko
Vyacheslav Yurkov Feb. 5, 2025, 7:06 a.m. UTC | #3
On 04.02.2025 14:18, Mikko Rapeli wrote:
> Hmm, doesn't this overwrite SRC_URI from systemd.inc?
>
> SRC_URI += "file://...patch" would amend the patch file.

Good catch!

>> -S = "${WORKDIR}/sources"
>> -UNPACKDIR = "${S}"
>> -
>> -do_install() {
>> -	install -d ${D}${bindir}
>> -	install -m 0755 ${S}/systemctl ${D}${bindir}
>> -}
>> +MESON_TARGET = "systemctl:executable"
>> +MESON_INSTALL_TAGS = "systemctl"
>> +EXTRA_OEMESON:append = " -Dlink-systemctl-shared=false"
> I wonder why this tag support is needed since MESON_TARGET already
> compiles only the correct executable with static linking. Is it there
> just to let meson handle the install step of a single systemctl
> executable?
>
> Or does it install more files, like config files too?

Correct. It installs much more when no tags specified :)

>
> I'm comparing this to a draft systemd-boot-native recipe for ukify
> which I had and which sets the build target but installs manually:
>
> MESON_TARGET = "ukify"
>
> EXTRA_OEMESON += "-Dnobody-user=nobody \
>      -Dnobody-group=nogroup \
>      -Drootlibdir=${rootlibdir} \
>      -Drootprefix=${rootprefix} \
>      -Ddefault-locale=C \
>      -Dmode=release \
>      -Dsystem-alloc-uid-min=101 \
>      -Dsystem-uid-max=999 \
>      -Dsystem-alloc-gid-min=101 \
>      -Dsystem-gid-max=999 \
> "
>
> do_install() {
>      install -d ${D}${bindir}/
>      install -m 0755 ${S}/src/ukify/ukify.py ${D}${bindir}/ukify
> }
>
> So the custom do_install() step could be avoided if systemd meson config
> would have "install_tag" for ukify too?

Correct. There's more discussion here 
https://github.com/systemd/systemd/pull/36243 , but if we need more 
tags, they can be added.

>
> Current systemd-boot-native recipe installs/copies the unmodified ukify.py
> from source tree and uses that in native. It doesn't run meson build for it
> and thus things like version details are incorrect. Also some additional tools
> like systemd-measure, systemd-sbsign etc are not compiled so some usecases may
> not be supported atm. If those would also include the install tags, then they
> could be compiled and installed too, I presume.

Yes, that would be an option as well

Slava
Böszörményi Zoltán Feb. 5, 2025, 8:30 a.m. UTC | #4
2025. 02. 04. 11:53 keltezéssel, Vyacheslav Yurkov via lists.openembedded.org írta:
> From: Vyacheslav Yurkov <uvv.mail@gmail.com>
>
> Instead of the python re-implementation build the actual systemctl from
> the systemd source tree. The python script was used when systemd didn't
> provide an option to build individual executables. It is possible in the
> meantime, so instead of always adapting the script when there's a new
> functionality, we simply use upstream implementation.

Finally, "systemctl --set-default mytarget" can be used in images.
Thank you!
diff mbox series

Patch

diff --git a/meta/recipes-core/systemd/systemd-systemctl-native.bb b/meta/recipes-core/systemd/systemd-systemctl-native.bb
index ffa024caef..57bb1ab830 100644
--- a/meta/recipes-core/systemd/systemd-systemctl-native.bb
+++ b/meta/recipes-core/systemd/systemd-systemctl-native.bb
@@ -1,17 +1,13 @@ 
-SUMMARY = "Wrapper for enabling systemd services"
+SUMMARY = "Systemctl executable from systemd"
 
-LICENSE = "MIT"
-LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
+require systemd.inc
 
+DEPENDS = "gperf-native libcap-native util-linux-native python3-jinja2-native"
 
-inherit native
+inherit pkgconfig meson native
 
-SRC_URI = "file://systemctl"
+SRC_URI = "file://0001-meson-add-install-tag-for-systemctl.patch"
 
-S = "${WORKDIR}/sources"
-UNPACKDIR = "${S}"
-
-do_install() {
-	install -d ${D}${bindir}
-	install -m 0755 ${S}/systemctl ${D}${bindir}
-}
+MESON_TARGET = "systemctl:executable"
+MESON_INSTALL_TAGS = "systemctl"
+EXTRA_OEMESON:append = " -Dlink-systemctl-shared=false"
diff --git a/meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch b/meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch
new file mode 100644
index 0000000000..a9b3e62708
--- /dev/null
+++ b/meta/recipes-core/systemd/systemd-systemctl/0001-meson-add-install-tag-for-systemctl.patch
@@ -0,0 +1,25 @@ 
+From fbf1ae3b7bd074a8d3bfb741f54b8539123399f1 Mon Sep 17 00:00:00 2001
+From: Vyacheslav Yurkov <uvv.mail@gmail.com>
+Date: Sun, 2 Feb 2025 10:13:38 +0100
+Subject: [PATCH] meson: add install tag for systemctl
+
+Upstream-Status: Backport
+[https://github.com/systemd/systemd/commit/b1e5a7aa3f1e552c56d5adbeed6ff67d88d1e103]
+
+Signed-off-by: Vyacheslav Yurkov <uvv.mail@gmail.com>
+---
+ src/systemctl/meson.build | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/src/systemctl/meson.build b/src/systemctl/meson.build
+index 88f73bf502..46218dc8ef 100644
+--- a/src/systemctl/meson.build
++++ b/src/systemctl/meson.build
+@@ -61,6 +61,7 @@ executables += [
+                         libzstd_cflags,
+                         threads,
+                 ],
++                'install_tag' : 'systemctl',
+         },
+         fuzz_template + {
+                 'sources' : [
diff --git a/meta/recipes-core/systemd/systemd-systemctl/systemctl b/meta/recipes-core/systemd/systemd-systemctl/systemctl
deleted file mode 100755
index 81c246a5b2..0000000000
--- a/meta/recipes-core/systemd/systemd-systemctl/systemctl
+++ /dev/null
@@ -1,366 +0,0 @@ 
-#!/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 itertools import chain
-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"""
-
-    _clearable_keys = ['WantedBy']
-
-    def __init__(self, root, path, instance_unit_name, unit_type):
-        self.sections = dict()
-        self._parse(root, path)
-        dirname = os.path.basename(path.name) + ".d"
-        for location in locations:
-            files = (root / location / unit_type / dirname).glob("*.conf")
-            if instance_unit_name:
-                inst_dirname = instance_unit_name + ".d"
-                files = chain(files, (root / location / unit_type / inst_dirname).glob("*.conf"))
-            for path2 in sorted(files):
-                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()
-
-                # If we come across a "key=" line for a "clearable key", then
-                # forget all preceding assignments. This works because we are
-                # processing files in correct parse order.
-                if k in self._clearable_keys and not v:
-                    del section[k]
-                    continue
-
-                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, unit_type):
-        self.root = root
-        self.unit = unit
-        self.unit_type = unit_type
-        self.config = None
-
-    def _path_for_unit(self, unit):
-        for location in locations:
-            path = self.root / location / self.unit_type / unit
-            if path.exists() or path.is_symlink():
-                return path
-
-        raise SystemdUnitNotFoundError(self.root, unit)
-
-    def _process_deps(self, config, service, location, prop, dirstem, instance):
-        systemdir = self.root / SYSCONFDIR / "systemd" / self.unit_type
-
-        target = ROOT / location.relative_to(self.root)
-        try:
-            for dependent in config.get('Install', prop):
-                # expand any %i to instance (ignoring escape sequence %%)
-                dependent = re.sub("([^%](%%)*)%i", "\\g<1>{}".format(instance), dependent)
-                wants = systemdir / "{}.{}".format(dependent, dirstem) / service
-                add_link(wants, target)
-
-        except KeyError:
-            pass
-
-    def enable(self, units_enabled=[]):
-        # 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)
-        instance_unit_name = None
-        if template:
-            instance = template.group('instance')
-            if instance != "":
-                instance_unit_name = self.unit
-            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, instance_unit_name, self.unit_type)
-        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', instance)
-        self._process_deps(config, service, path, 'RequiredBy', 'requires', instance)
-
-        try:
-            for also in config.get('Install', 'Also'):
-                try:
-                     units_enabled.append(unit)
-                     if also not in units_enabled:
-                        SystemdUnit(self.root, also, self.unit_type).enable(units_enabled)
-                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" / self.unit_type
-        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" / self.unit_type
-        add_link(systemdir / self.unit, "/dev/null")
-
-
-def collect_services(root, unit_type):
-    """Collect list of service files"""
-    services = set()
-    for location in locations:
-        paths = (root / location / unit_type).glob("*")
-        for path in paths:
-            if path.is_dir():
-                continue
-            services.add(path.name)
-
-    return services
-
-
-def preset_all(root, unit_type):
-    presets = Presets('{}-preset'.format(unit_type), root)
-    services = collect_services(root, unit_type)
-
-    for service in services:
-        state = presets.state(service)
-
-        if state == "enable" or state is None:
-            try:
-                SystemdUnit(root, service, unit_type).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')
-    parser.add_argument('--global', dest="opt_global", action="store_true", default=False)
-
-    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
-
-    unit_type = "user" if args.opt_global else "system"
-
-    if command == "mask":
-        for service in args.service:
-            try:
-                SystemdUnit(root, service, unit_type).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, unit_type).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, unit_type)
-    else:
-        raise RuntimeError()
-
-
-if __name__ == '__main__':
-    main()