Configure default resource and data directories from CMake

As anbox is expected to installed in two ways (`snap` or `make install`),
it should be enough to get `snap` ENV or configure by cmake.

.gitignore

@@ -2,6 +2,8 @@ build*/
 parts/
 stage/
 prime/
+snap/
+android-images/
 *.snap
 CMakeLists.txt.user
 *.o.cmd
@@ -14,6 +16,8 @@ CMakeLists.txt.user
 modules.order
 .tmp_versions
 .idea
+src/anbox/config.h
+
 
 debian/anbox-modules-dkms.debhelper.log
 debian/anbox-modules-dkms.substvars

CMakeLists.txt

@@ -108,6 +108,12 @@ endif()
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/src/anbox/build/version.h.in
                ${CMAKE_CURRENT_SOURCE_DIR}/src/anbox/build/version.h)
 
+set(ANBOX_RESOURCE_DIR "${CMAKE_INSTALL_DATADIR}/anbox")
+set(ANBOX_RESOURCE_DIR_FULL "${CMAKE_INSTALL_FULL_DATADIR}/anbox")
+set(ANBOX_STATEDIR_FULL "${CMAKE_INSTALL_FULL_LOCALSTATEDIR}/anbox")
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/src/anbox/config.h.in
+               ${CMAKE_CURRENT_SOURCE_DIR}/src/anbox/config.h)
+
 add_subdirectory(external)
 add_subdirectory(src)
 add_subdirectory(tests)
@@ -118,7 +124,7 @@ if (NOT "${HOST_CMAKE_C_COMPILER}" STREQUAL "")
   message(STATUS "Host C compiler: ${HOST_CMAKE_CXX_COMPILER}")
 endif()
 
-install(FILES data/ui/loading-screen.png DESTINATION share/anbox/ui)
+install(FILES data/ui/loading-screen.png DESTINATION ${ANBOX_RESOURCE_DIR}/ui)
 
 # uninstall target
 configure_file("${CMAKE_CURRENT_SOURCE_DIR}/cmake_uninstall.cmake.in"

src/anbox/config.cpp

@@ -90,18 +90,11 @@ anbox::SystemConfiguration::SystemConfiguration() {
     const auto snap_path = utils::get_env_value("SNAP");
     if (!snap_path.empty()) {
       return fs::path(snap_path) / "usr/share/anbox";
-    }
-
-    const std::string exe = utils::process_get_exe_path(::getpid());
-    const std::size_t pos = exe.rfind("/bin/anbox");
-    if (pos != std::string::npos) {
-      const std::string leading_path = exe.substr(0, pos);
-      return fs::path(leading_path) / "share/anbox";
     } else {
-      return "/usr/local/share/anbox";
+      return default_resource_path;
     }
   };
 
   resource_path = gen_resource_path();
-  data_path = "/var/local/lib/anbox";
+  data_path = default_path_path;
 }

src/anbox/config.h → src/anbox/config.h.in

@@ -48,6 +48,10 @@ class SystemConfiguration {
   boost::filesystem::path data_path;
   boost::filesystem::path resource_path;
 
+ private:
+  static constexpr const char *default_resource_path{"@ANBOX_RESOURCE_DIR_FULL@"};
+  static constexpr const char *default_path_path{"@ANBOX_STATEDIR_FULL@"};
+
 };
 }  // namespace anbox