kapi: formally extract device registry

1 files changed, 106 insertions, 0 deletions

diff --git a/kernel/kapi/devices/device_registry.cpp b/kernel/kapi/devices/device_registry.cpp
new file mode 100644
index 00000000..aca0e7fe
--- /dev/null
+++ b/kernel/kapi/devices/device_registry.cpp
@@ -0,0 +1,106 @@
+#include <kapi/devices/device_registry.hpp>
+
+#include <kapi/devices/device.hpp>
+#include <kapi/system.hpp>
+
+#include <kstd/memory.hpp>
+#include <kstd/print.hpp>
+#include <kstd/string.hpp>
+#include <kstd/vector.hpp>
+
+#include <optional>
+#include <string_view>
+#include <utility>
+
+namespace kapi::devices
+{
+
+  namespace
+  {
+    auto constinit instance = std::optional<device_registry>{};
+  }
+
+  auto device_registry::init() -> void
+  {
+    if (instance)
+    {
+      system::panic("[OS:DEV] Device registry has already been initialized");
+    }
+
+    instance = device_registry{};
+  }
+
+  auto device_registry::get() -> device_registry &
+  {
+    if (!instance)
+    {
+      system::panic("[OS:DEV] Device registry has not been initialized");
+    }
+
+    return *instance;
+  }
+
+  auto device_registry::add(kstd::shared_ptr<device> device) -> bool
+  {
+    if (!device)
+    {
+      return false;
+    }
+
+    kstd::println("[OS:DEV] Registering device {}", device->name());
+
+    auto found = m_devices.find(device->name());
+    if (found != m_devices.end())
+    {
+      if (!found->second.expired())
+      {
+        return false;
+      }
+
+      found->second = device;
+      return true;
+    }
+
+    return m_devices.emplace(device->name(), device).second;
+  }
+
+  auto device_registry::remove(device &) -> bool
+  {
+    kstd::println("[OS:DEV] TODO: implement device deregistration");
+    return false;
+  }
+
+  auto device_registry::find(std::string_view name) const -> kstd::shared_ptr<device>
+  {
+    auto found = m_devices.find(kstd::string{name});
+    if (found == m_devices.end())
+    {
+      return nullptr;
+    }
+
+    return found->second.lock();
+  }
+
+  auto device_registry::all() const -> kstd::vector<kstd::shared_ptr<device>>
+  {
+    auto result = kstd::vector<kstd::shared_ptr<device>>{};
+
+    for (auto const & [name, weak_device] : m_devices)
+    {
+      if (auto device = weak_device.lock())
+      {
+        result.push_back(std::move(device));
+      }
+    }
+
+    return result;
+  }
+}  // namespace kapi::devices
+
+namespace kapi::test_support::devices
+{
+  auto deinit_device_registry() -> void
+  {
+    kapi::devices::instance.reset();
+  }
+}  // namespace kapi::test_support::devices
\ No newline at end of file