core: ExecCondition= for services

Closes #10596

test/fuzz/fuzz-unit-file/directives.service

@@ -83,6 +83,7 @@ DirectoryNotEmpty=
 Documentation=
 DynamicUser=
 ExecReload=
+ExecCondition=
 ExecStart=
 ExecStartPost=
 ExecStartPre=

test/meson.build

@@ -56,6 +56,8 @@ test_data_files = '''
         test-execute/exec-capabilityboundingset-merge.service
         test-execute/exec-capabilityboundingset-reset.service
         test-execute/exec-capabilityboundingset-simple.service
+        test-execute/exec-condition-failed.service
+        test-execute/exec-condition-skip.service
         test-execute/exec-cpuaffinity1.service
         test-execute/exec-cpuaffinity2.service
         test-execute/exec-cpuaffinity3.service

test/test-execute/exec-condition-failed.service

@@ -0,0 +1,11 @@
+[Unit]
+Description=Test for exec condition that fails the unit
+
+[Service]
+Type=oneshot
+
+# exit 255 will fail the unit
+ExecCondition=/bin/sh -c 'exit 255'
+
+# This should not get run
+ExecStart=/bin/sh -c 'true'

test/test-execute/exec-condition-skip.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=Test for exec condition that triggers skipping
+
+[Service]
+Type=oneshot
+
+# exit codes [1, 254] will result in skipping the rest of execution
+ExecCondition=/bin/sh -c 'exit 0'
+ExecCondition=/bin/sh -c 'exit 254'
+
+# This would normally fail the unit but will not get run due to the skip above
+ExecCondition=/bin/sh -c 'exit 255'
+
+# This should not get run
+ExecStart=/bin/sh -c 'true'