refactor: split Linux system service adapter

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Split the Linux system adapter into focused single-instance, notification,
+  tray, autostart, secure-storage, and crash/shutdown implementation units,
+  with one private XDG/D-Bus support core and no public API change.
 - Make AppImage the signed Linux update payload when that format is enabled,
   emit its SHA-256 sidecar, and add install-kind-aware update selection so
   AppImage, portable, and package-manager installations cannot cross streams.

docs/architecture.md

@@ -89,6 +89,14 @@ The Swift implementation is intentionally not the framework's specification. `do
 
 The GTK4 host follows the Windows C++ contract but uses a Unix `socketpair` for the in-process RVT1 transport. Racket CS is linked statically, while the UI remains an ordinary GTK4 application. Backend completions are returned to GLib's main loop before widgets are touched.
 
+Linux system integration is split by operating-system responsibility under
+`platform/linux/system`: single-instance activation, notifications, tray,
+autostart, secure storage, and crash/shutdown each have one implementation
+unit. `system_services.cpp` only assembles public capability discovery and
+activation arguments; `system_services_internal.*` is a private XDG, D-Bus,
+and low-level I/O support layer. Native applications continue to include only
+`system_services.hpp`.
+
 ## Runtime ownership
 
 Rivet treats a Racket runtime as process-scoped infrastructure:

examples/taskboard/linux/CMakeLists.txt

@@ -49,7 +49,14 @@ endif()
 add_executable(RivetHost
   src/main.cpp
   "${RIVET_ROOT}/platform/linux/runtime/backend.cpp"
+  "${RIVET_ROOT}/platform/linux/system/autostart.cpp"
+  "${RIVET_ROOT}/platform/linux/system/crash_shutdown.cpp"
+  "${RIVET_ROOT}/platform/linux/system/notifications.cpp"
+  "${RIVET_ROOT}/platform/linux/system/secure_storage.cpp"
+  "${RIVET_ROOT}/platform/linux/system/single_instance.cpp"
   "${RIVET_ROOT}/platform/linux/system/system_services.cpp"
+  "${RIVET_ROOT}/platform/linux/system/system_services_internal.cpp"
+  "${RIVET_ROOT}/platform/linux/system/tray.cpp"
   "${RIVET_ROOT}/platform/linux/theme/theme.cpp"
   "${RIVET_ROOT}/runtime/src/protocol.cpp"
 )

platform/linux/Integration/CMakeLists.txt

@@ -29,7 +29,14 @@ pkg_check_modules(LIBSECRET IMPORTED_TARGET libsecret-1)
 add_executable(RivetIntegration
   main.cpp
   ../runtime/backend.cpp
+  ../system/autostart.cpp
+  ../system/crash_shutdown.cpp
+  ../system/notifications.cpp
+  ../system/secure_storage.cpp
+  ../system/single_instance.cpp
   ../system/system_services.cpp
+  ../system/system_services_internal.cpp
+  ../system/tray.cpp
   ${RIVET_ROOT}/runtime/src/protocol.cpp
 )
 

platform/linux/host/CMakeLists.txt

@@ -49,7 +49,14 @@ endif()
 add_executable(RivetHost
   src/main.cpp
   "${RIVET_ROOT}/platform/linux/runtime/backend.cpp"
+  "${RIVET_ROOT}/platform/linux/system/autostart.cpp"
+  "${RIVET_ROOT}/platform/linux/system/crash_shutdown.cpp"
+  "${RIVET_ROOT}/platform/linux/system/notifications.cpp"
+  "${RIVET_ROOT}/platform/linux/system/secure_storage.cpp"
+  "${RIVET_ROOT}/platform/linux/system/single_instance.cpp"
   "${RIVET_ROOT}/platform/linux/system/system_services.cpp"
+  "${RIVET_ROOT}/platform/linux/system/system_services_internal.cpp"
+  "${RIVET_ROOT}/platform/linux/system/tray.cpp"
   "${RIVET_ROOT}/platform/linux/theme/theme.cpp"
   "${RIVET_ROOT}/runtime/src/protocol.cpp"
 )

platform/linux/host/README.md

@@ -21,8 +21,14 @@ platform/linux/
 │   ├── backend.hpp        # rivet::linux_runtime::Backend — same contract as rivet::windows
 │   └── backend.cpp        # racketcs boot + RVT1-over-socketpair transport
 ├── system/
-│   ├── system_services.hpp  # rivet::system — single-instance, notifications,
-│   └── system_services.cpp  #   autostart, Secret Service, crash hook, capabilities
+│   ├── system_services.hpp  # public rivet::system surface
+│   ├── system_services.cpp  # capability discovery + activation arguments
+│   ├── single_instance.cpp  # local activation lease and forwarding
+│   ├── notifications.cpp    # freedesktop notifications
+│   ├── tray.cpp             # StatusNotifierItem + dbusmenu
+│   ├── autostart.cpp        # XDG autostart entries
+│   ├── secure_storage.cpp   # Secret Service through libsecret
+│   └── crash_shutdown.cpp   # fatal-signal record + orderly termination
 └── host/
     ├── GeneratedBackend.hpp  # scaffold schema; raco rivet build replaces it
     ├── CMakeLists.txt

platform/linux/system/autostart.cpp

@@ -0,0 +1,92 @@
+#include "system_services.hpp"
+#include "system_services_internal.hpp"
+
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <cerrno>
+#include <cstring>
+#include <stdexcept>
+
+namespace rivet::system {
+namespace {
+
+std::string autostart_path(std::string const& application_id) {
+  return detail::xdg_config_home() + "/autostart/" +
+         detail::sanitize_file_name(application_id) + ".desktop";
+}
+
+}  // namespace
+
+using detail::write_all;
+using detail::xdg_config_home;
+
+bool Autostart::Enabled(std::string const& application_id) {
+  std::string path = autostart_path(application_id);
+  int fd = ::open(path.c_str(), O_RDONLY | O_CLOEXEC);
+  if (fd < 0) {
+    if (errno == ENOENT) return false;
+    throw std::runtime_error(std::string("autostart check failed: ") +
+                             std::strerror(errno));
+  }
+  std::string contents;
+  char buffer[1024];
+  while (true) {
+    ssize_t received = ::read(fd, buffer, sizeof(buffer));
+    if (received < 0) {
+      if (errno == EINTR) continue;
+      int saved = errno;
+      ::close(fd);
+      throw std::runtime_error(std::string("autostart read failed: ") +
+                               std::strerror(saved));
+    }
+    if (received == 0) break;
+    contents.append(buffer, static_cast<std::size_t>(received));
+  }
+  ::close(fd);
+
+  // Follow the Desktop Entry spec's disabling keys.
+  if (contents.find("Hidden=true") != std::string::npos) return false;
+  if (contents.find("X-GNOME-Autostart-enabled=false") != std::string::npos)
+    return false;
+  return true;
+}
+
+void Autostart::SetEnabled(std::string const& application_id,
+                           std::string const& executable, bool enabled) {
+  std::string path = autostart_path(application_id);
+  if (!enabled) {
+    if (::unlink(path.c_str()) != 0 && errno != ENOENT)
+      throw std::runtime_error(std::string("autostart removal failed: ") +
+                               std::strerror(errno));
+    return;
+  }
+
+  std::string directory = xdg_config_home() + "/autostart";
+  ::mkdir(xdg_config_home().c_str(), 0755);
+  ::mkdir(directory.c_str(), 0755);
+
+  std::string contents =
+      "[Desktop Entry]\n"
+      "Type=Application\n"
+      "Name=" + application_id + "\n"
+      "Exec=" + executable + "\n"
+      "Terminal=false\n"
+      "X-GNOME-Autostart-enabled=true\n";
+  int fd = ::open(path.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC, 0644);
+  if (fd < 0)
+    throw std::runtime_error(std::string("autostart write failed: ") +
+                             std::strerror(errno));
+  try {
+    write_all(fd, contents.data(), contents.size());
+  } catch (...) {
+    ::close(fd);
+    throw;
+  }
+  ::close(fd);
+}
+
+
+
+}  // namespace rivet::system