Add elogind support and use pkg-config to get libsystemd version

igo95862 · igo95862 · commit 570a1de11d57 · 2022-02-05T21:45:19.000+03:00
diff --git a/.github/workflows/ubuntu_test.yml b/.github/workflows/ubuntu_test.yml
@@ -36,7 +36,7 @@ jobs:
         run: |
           sudo apt update
           sudo apt install python3-setuptools python3-dev libsystemd-dev \
-            systemd dbus python3 gcc
+            systemd dbus python3 gcc pkg-config
       - name: Build extension
         env:
           PYTHON_SDBUS_USE_LIMITED_API: "1"
diff --git a/README.md b/README.md
@@ -9,7 +9,7 @@ Features:
 * Asyncio and blocking calls.
 * Type hints. (`mypy --strict` compatible)
 * No Python 2 legacy.
-* Based on fast sd-bus from systemd.
+* Based on fast sd-bus from systemd. (also supports elogind)
 * Unified client/server interface classes. Write interface once!
 * Dbus methods can have keyword and default arguments.
 
@@ -50,9 +50,10 @@ platforms.
 * Python 3.8 or higher.
 * Python headers. (`python3-dev` package on ubuntu)
 * GCC.
-* libsystemd. (comes with systemd)
+* libsystemd or libelogind
 * libsystemd headers. (`libsystemd-dev` package on ubuntu)
 * Python setuptools.
+* pkg-config
 
 Systemd version should be higher than 246.
 
diff --git a/setup.py b/setup.py
@@ -20,7 +20,7 @@
 from __future__ import annotations
 
 from os import environ
-from subprocess import DEVNULL, PIPE, CalledProcessError
+from subprocess import DEVNULL, PIPE
 from subprocess import run as subprocess_run
 from typing import List, Optional, Tuple
 
@@ -30,49 +30,47 @@
 c_macros: List[Tuple[str, Optional[str]]] = []
 
 
-def get_libsystemd_version() -> Tuple[int, int, int]:
+def get_libsystemd_version() -> int:
     process = subprocess_run(
-        args=('ldconfig', '-f', '/dev/null', '-C', '/dev/null',
-              '-v', '-N', '-X'),
+        args=('pkg-config', '--modversion', 'libsystemd'),
         stderr=DEVNULL,
         stdout=PIPE,
+        check=True,
     )
 
-    try:
-        process.check_returncode()
-    except CalledProcessError:
-        return 0, 0, 0
-
     result_str = process.stdout.decode('utf-8')
 
-    for line in result_str.splitlines():
-        if 'libsystemd.so' in line:
-            version_str = line.split('libsystemd.so')[-1]
-            semver_strs = version_str.split('.')
-            return (
-                int(semver_strs[1]),
-                int(semver_strs[2]),
-                int(semver_strs[3]),
-            )
-
-    return 0, 0, 0
+    return int(result_str)
 
 
 if not environ.get('PYTHON_SDBUS_USE_IGNORE_SYSTEMD_VERSION'):
-    LIBSYSTEMD_MAJOR, LIBSYSTEMD_MINOR, LIBSYTEMD_PATCH \
-        = get_libsystemd_version()
+    systemd_version = get_libsystemd_version()
 
-    if LIBSYSTEMD_MAJOR <= 0 and LIBSYSTEMD_MINOR < 29:
+    if systemd_version < 246:
         c_macros.append(('LIBSYSTEMD_NO_VALIDATION_FUNCS', None))
 
-    if LIBSYSTEMD_MAJOR <= 0 and LIBSYSTEMD_MINOR < 31:
+    if systemd_version < 248:
         c_macros.append(('LIBSYSTEMD_NO_OPEN_USER_MACHINE', None))
 
-link_arguments: List[str] = ['-lsystemd']
+
+def get_link_arguments() -> List[str]:
+    process = subprocess_run(
+        args=('pkg-config', '--libs-only-l', 'libsystemd'),
+        stderr=DEVNULL,
+        stdout=PIPE,
+        check=True,
+    )
+
+    result_str = process.stdout.decode('utf-8')
+
+    return result_str.rstrip(' \n').split(' ')
+
+
+link_arguments: List[str] = get_link_arguments()
 
 if environ.get('PYTHON_SDBUS_USE_STATIC_LINK'):
     # Link statically against libsystemd and libcap
-    link_arguments = ['-Wl,-Bstatic', '-lsystemd', '-lcap',
+    link_arguments = ['-Wl,-Bstatic', *link_arguments, '-lcap',
                       '-Wl,-Bdynamic', '-lrt', '-lpthread']
 
 link_arguments.append('-flto')
diff --git a/src/sdbus/sd_bus_internals_funcs.c b/src/sdbus/sd_bus_internals_funcs.c
@@ -65,7 +65,7 @@ static SdBusObject* sd_bus_py_open_user_machine(PyObject* Py_UNUSED(self), PyObj
         CALL_SD_BUS_AND_CHECK(sd_bus_open_user_machine(&(new_sd_bus->sd_bus_ref), remote_host_char_ptr));
         return new_sd_bus;
 #else
-        PyErr_SetString(PyExc_NotImplementedError, "libsystemd<0.31.0 does not opening machine user bus");
+        PyErr_SetString(PyExc_NotImplementedError, "libsystemd < 248 does not support opening machine user bus");
         return NULL;
 #endif
 }
@@ -86,7 +86,7 @@ static PyObject* encode_object_path(PyObject* Py_UNUSED(self), PyObject* args) {
         CALL_PYTHON_BOOL_CHECK(PyArg_ParseTuple(args, "ss", &prefix_char_ptr, &external_char_ptr, NULL));
 #endif
 #ifdef LIBSYSTEMD_NO_VALIDATION_FUNCS
-        PyErr_SetString(PyExc_NotImplementedError, "libsystemd<0.29.0 does not support validation functions");
+        PyErr_SetString(PyExc_NotImplementedError, "libsystemd < 246 does not support validation functions");
         return NULL;
 #else
 
