Add support for using system bus

CMakeLists.txt

@@ -8,9 +8,11 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra")
 set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -O0 -Wall -Wextra")
 
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
+option(USE_USER_BUS "Uses user bus" OFF)
+
 find_package(Git REQUIRED)
 
 # Set version number and update submodules
@@ -46,5 +48,9 @@ message("LogiOps Version Number: ${LOGIOPS_VERSION}")
 
 add_definitions( -DLOGIOPS_VERSION="${LOGIOPS_VERSION}")
 
+if(USE_USER_BUS)
+    add_definitions(-DUSE_USER_BUS)
+endif()
+
 add_subdirectory(src/ipcgull)
 add_subdirectory(src/logid)

README.md

@@ -33,12 +33,18 @@ To build this project, run:
 ```bash
 mkdir build
 cd build
-cmake ..
+cmake -DCMAKE_BUILD_TYPE=Release ..
 make
 ```
 
 To install, run `sudo make install` after building. You can set the daemon to start at boot by running `sudo systemctl enable logid` or `sudo systemctl enable --now logid` if you want to enable and start the daemon.
 
+## Development
+
+The project may only run as root, but for development purposes, you may find it
+convenient to run as non-root on the user bus. You must compile with the CMake
+flag `-DUSE_USER_BUS=ON` to use the user bus.
+
 ## Donate
 This program is (and will always be) provided free of charge. If you would like to support the development of this project by donating, you can donate to my Ko-Fi below.
 

src/logid/CMakeLists.txt

@@ -69,6 +69,7 @@ add_executable(logid
 set_target_properties(logid PROPERTIES RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
 
 pkg_check_modules(PC_EVDEV libevdev REQUIRED)
+pkg_check_modules(DBUS "dbus-1")
 pkg_check_modules(SYSTEMD "systemd")
 pkg_check_modules(LIBCONFIG libconfig REQUIRED)
 pkg_check_modules(LIBUDEV libudev REQUIRED)
@@ -88,13 +89,17 @@ target_link_libraries(logid ${CMAKE_THREAD_LIBS_INIT} ${EVDEV_LIBRARY} config++
 
 install(TARGETS logid DESTINATION bin)
 
-if (SYSTEMD_FOUND AND "${SYSTEMD_SERVICES_INSTALL_DIR}" STREQUAL "")
+if (SYSTEMD_FOUND)
+    if ("${SYSTEMD_SERVICES_INSTALL_DIR}" STREQUAL "")
         execute_process(COMMAND ${PKG_CONFIG_EXECUTABLE}
                 --variable=systemdsystemunitdir systemd
                 OUTPUT_VARIABLE SYSTEMD_SERVICES_INSTALL_DIR)
         string(REGEX REPLACE "[ \t\n]+" "" SYSTEMD_SERVICES_INSTALL_DIR
                 "${SYSTEMD_SERVICES_INSTALL_DIR}")
-    configure_file(logid.service.cmake ${CMAKE_BINARY_DIR}/logid.service)
+    endif ()
+
+    # Install systemd service
+    configure_file(logid.service.in ${CMAKE_BINARY_DIR}/logid.service)
     message(STATUS "systemd units will be installed at ${SYSTEMD_SERVICES_INSTALL_DIR}")
     install(FILES ${CMAKE_BINARY_DIR}/logid.service
             DESTINATION ${SYSTEMD_SERVICES_INSTALL_DIR}
@@ -102,3 +107,14 @@ if (SYSTEMD_FOUND AND "${SYSTEMD_SERVICES_INSTALL_DIR}" STREQUAL "")
 elseif (NOT SYSTEMD_FOUND AND SYSTEMD_SERVICES_INSTALL_DIR)
     message(FATAL_ERROR "systemd is not found w/ pkg-config but SYSTEMD_SERVICES_INSTALL_DIR is defined.")
 endif ()
+
+if(DBUS_FOUND)
+    # Install DBus conf
+    # TODO: Is there a better way of setting the system policy directory?
+    set(DBUS_SYSTEM_POLICY_INSTALL_DIR "/usr/share/dbus-1/system.d")
+    configure_file(logiops-dbus.conf.in ${CMAKE_BINARY_DIR}/pizza.pixl.LogiOps.conf)
+    message(STATUS "dbus system policy will be installed at ${DBUS_SYSTEM_POLICY_INSTALL_DIR}")
+    install(FILES ${CMAKE_BINARY_DIR}/pizza.pixl.LogiOps.conf
+            DESTINATION ${DBUS_SYSTEM_POLICY_INSTALL_DIR}
+            COMPONENT cp)
+endif()

src/logid/logid.cpp

@@ -142,7 +142,13 @@ int main(int argc, char** argv) {
         config = std::make_shared<Configuration>();
     }
 
-    auto server = ipcgull::make_server(SERVICE_ROOT_NAME, server_root_node, ipcgull::IPCGULL_USER);
+#ifdef USE_USER_BUS
+    auto server_bus = ipcgull::IPCGULL_USER;
+#else
+    auto server_bus = ipcgull::IPCGULL_SYSTEM;
+#endif
+
+    auto server = ipcgull::make_server(SERVICE_ROOT_NAME, server_root_node, server_bus);
 
     //Create a virtual input device
     try {
@@ -161,6 +167,7 @@ int main(int argc, char** argv) {
         server->start();
     } catch (ipcgull::connection_failed& e) {
         logPrintf(ERROR, "Lost IPC connection, terminating.");
+        return EXIT_FAILURE;
     }
 
     return EXIT_SUCCESS;

src/logid/logid.service.in

@@ -8,7 +8,6 @@ Wants=multi-user.target
 Type=simple
 ExecStart=${CMAKE_INSTALL_PREFIX}/bin/logid
 User=root
-ExecReload=/bin/kill -HUP $MAINPID
 Restart=on-failure
 
 [Install]

src/logid/logiops-dbus.conf.in

@@ -0,0 +1,16 @@
+<!DOCTYPE busconfig PUBLIC
+ "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
+ "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
+
+<busconfig>
+  <!-- Only root user can own the service -->
+  <policy user="root">
+    <allow own="pizza.pixl.LogiOps"/>
+  </policy>
+
+  <!-- Allow anyone to invoke methods on server, except SetHostName -->
+  <policy context="default">
+    <allow send_destination="pizza.pixl.LogiOps"/>
+    <allow receive_sender="pizza.pixl.LogiOps"/>
+  </policy>
+</busconfig>