systemd/test/test-execute/exec-temporaryfilesystem-ro.service

[Unit]
Description=Test for TemporaryFileSystem with read-only mode

[Service]
Type=oneshot

# Check directories exist
ExecStart=/bin/sh -c 'test -d /var/test-exec-temporaryfilesystem/rw && test -d /var/test-exec-temporaryfilesystem/ro'

# Check TemporaryFileSystem= are empty
ExecStart=/bin/sh -c 'for i in $$(ls -A /var); do test $$i = test-exec-temporaryfilesystem || false; done'

# Cannot create a file in /var
ExecStart=/bin/sh -c '! touch /var/hoge'

# Create a file in /var/test-exec-temporaryfilesystem/rw
ExecStart=/bin/sh -c 'touch /var/test-exec-temporaryfilesystem/rw/thisisasimpletest-temporaryfilesystem'

# Then, the file can be access through /tmp
ExecStart=/bin/sh -c 'test -f /tmp/thisisasimpletest-temporaryfilesystem'

# Also, through /var/test-exec-temporaryfilesystem/ro
ExecStart=/bin/sh -c 'test -f /var/test-exec-temporaryfilesystem/ro/thisisasimpletest-temporaryfilesystem'

# The file cannot modify through /var/test-exec-temporaryfilesystem/ro
ExecStart=/bin/sh -c '! touch /var/test-exec-temporaryfilesystem/ro/thisisasimpletest-temporaryfilesystem'

# Cleanup
ExecStart=/bin/sh -c 'rm /tmp/thisisasimpletest-temporaryfilesystem'

TemporaryFileSystem=/var:ro
BindPaths=/tmp:/var/test-exec-temporaryfilesystem/rw
BindReadOnlyPaths=/tmp:/var/test-exec-temporaryfilesystem/ro