chore: replace some naked pointers

The coding guidelines explicitly prohibit the use of "naked"/C-style
pointers. However, there were some prominent examples in the kapi and
the core kernel source. This changeset replaces them with the
appropriate smart pointer types.

7 files changed, 39 insertions, 37 deletions

diff --git a/kernel/kapi/devices/bus.cpp b/kernel/kapi/devices/bus.cpp
index 300151d5..d956c3b8 100644
--- a/kernel/kapi/devices/bus.cpp
+++ b/kernel/kapi/devices/bus.cpp
@@ -84,15 +84,15 @@ namespace kapi::devices
     return m_devices;
   }
 
-  auto bus::query_facet(kapi::capabilities::facet_id facet) -> void *
+  auto bus::query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void>
   {
     if (facet == bus::id)
     {
-      return this;
+      return kstd::observer_ptr(this);
     }
     else if (facet == bus_protocol::id)
     {
-      return m_protocol;
+      return kstd::observer_ptr{m_protocol};
     }
 
     return device::query_facet(facet);
diff --git a/kernel/kapi/devices/device.cpp b/kernel/kapi/devices/device.cpp
index 2576e20a..3a3b7cc1 100644
--- a/kernel/kapi/devices/device.cpp
+++ b/kernel/kapi/devices/device.cpp
@@ -23,12 +23,12 @@ namespace kapi::devices
       : m_name(name)
   {}
 
-  auto device::facet(kapi::capabilities::facet_id facet) noexcept -> void *
+  auto device::facet(kapi::capabilities::facet_id facet) noexcept -> kstd::observer_ptr<void>
   {
     return query_facet(facet);
   }
 
-  auto device::facet(kapi::capabilities::facet_id facet) const noexcept -> void const *
+  auto device::facet(kapi::capabilities::facet_id facet) const noexcept -> kstd::observer_ptr<void const>
   {
     return const_cast<device *>(this)->query_facet(facet);
   }
@@ -61,10 +61,10 @@ namespace kapi::devices
     m_state = state;
   }
 
-  auto device::bound_driver() const noexcept -> driver *
+  auto device::bound_driver() const noexcept -> kstd::shared_ptr<driver>
   {
     auto guard = kstd::lock_guard{m_lock};
-    return m_driver.lock().get();
+    return m_driver.lock();
   }
 
   auto device::bind_driver(kstd::weak_ptr<struct driver> driver) -> void
@@ -114,7 +114,7 @@ namespace kapi::devices
     m_resources = std::move(resources);
   }
 
-  auto device::query_facet(kapi::capabilities::facet_id) -> void *
+  auto device::query_facet(kapi::capabilities::facet_id) -> kstd::observer_ptr<void>
   {
     return nullptr;
   }
diff --git a/kernel/kapi/devices/driver.cpp b/kernel/kapi/devices/driver.cpp
index 5ca92dc8..0f103cbc 100644
--- a/kernel/kapi/devices/driver.cpp
+++ b/kernel/kapi/devices/driver.cpp
@@ -1,6 +1,7 @@
 #include <kapi/capabilities/facet_id.hpp>
 #include <kapi/devices.hpp>
 
+#include <kstd/memory.hpp>
 #include <kstd/result.hpp>
 
 #include <cstdint>
@@ -29,7 +30,7 @@ namespace kapi::devices
     return kstd::success();
   }
 
-  auto driver::query_facet(kapi::capabilities::facet_id) -> void *
+  auto driver::query_facet(kapi::capabilities::facet_id) -> kstd::observer_ptr<void>
   {
     return nullptr;
   }
diff --git a/kernel/kapi/devices/driver.tests.cpp b/kernel/kapi/devices/driver.tests.cpp
index ee3fe577..38d07ed9 100644
--- a/kernel/kapi/devices/driver.tests.cpp
+++ b/kernel/kapi/devices/driver.tests.cpp
@@ -36,8 +36,8 @@ namespace
     [[nodiscard]] auto match(kapi::devices::device const & dev, kapi::devices::driver const & drv) const
         -> kstd::result<std::uint32_t> override
     {
-      auto const * signature = dev.facet<controller_signature>();
-      auto const * claim = drv.facet<controller_claim>();
+      auto const signature = dev.facet<controller_signature>();
+      auto const claim = drv.facet<controller_claim>();
       if (!signature || !claim || !std::ranges::contains(claim->supported_names(), signature->controller_name()))
       {
         return kstd::failure(kapi::devices::driver_match_errc::no_match);
@@ -65,11 +65,11 @@ namespace
     }
 
   protected:
-    auto query_facet(kapi::capabilities::facet_id facet) -> void * override
+    auto query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void> override
     {
       if (facet == controller_signature::id)
       {
-        return static_cast<controller_signature *>(this);
+        return kstd::make_observer<controller_signature>(this);
       }
       return kapi::devices::bus::query_facet(facet);
     }
@@ -101,11 +101,11 @@ namespace
     }
 
   protected:
-    auto query_facet(kapi::capabilities::facet_id facet) -> void * override
+    auto query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void> override
     {
       if (facet == leaf_signature::id)
       {
-        return static_cast<leaf_signature *>(this);
+        return kstd::make_observer<leaf_signature>(this);
       }
       return kapi::devices::device::query_facet(facet);
     }
@@ -123,9 +123,9 @@ namespace
     [[nodiscard]] auto match(kapi::devices::device const & dev, kapi::devices::driver const & drv) const
         -> kstd::result<std::uint32_t> override
     {
-      auto const * ident = dev.facet<leaf_signature>();
-      auto const * claims = drv.facet<leaf_claim>();
-      if (!ident || !claims || !std::ranges::contains(claims->supported_names(), ident->leaf_name()))
+      auto const signature = dev.facet<leaf_signature>();
+      auto const claims = drv.facet<leaf_claim>();
+      if (!signature || !claims || !std::ranges::contains(claims->supported_names(), signature->leaf_name()))
       {
         return kstd::failure(kapi::devices::driver_match_errc::no_match);
       }
@@ -166,11 +166,11 @@ namespace
     }
 
   protected:
-    auto query_facet(kapi::capabilities::facet_id facet) -> void * override
+    auto query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void> override
     {
       if (facet == controller_claim::id)
       {
-        return static_cast<controller_claim *>(this);
+        return kstd::make_observer<controller_claim>(this);
       }
 
       return kapi::devices::driver::query_facet(facet);
@@ -198,11 +198,11 @@ namespace
     }
 
   protected:
-    auto query_facet(kapi::capabilities::facet_id facet) -> void * override
+    auto query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void> override
     {
       if (facet == leaf_claim::id)
       {
-        return static_cast<leaf_claim *>(this);
+        return kstd::make_observer<leaf_claim>(this);
       }
 
       return kapi::devices::driver::query_facet(facet);
@@ -213,7 +213,8 @@ namespace
 SCENARIO("a bound controller driver can attach a further, independently-typed bus protocol of its own",
          "[devices][driver][stacking]")
 {
-  GIVEN("a controller bus, a controller driver, and a leaf driver, none aware of each other's identification scheme")
+  GIVEN(
+      "a controller bus, a controller driver, and a leaf driver, none aware of each other's signatureification scheme")
   {
     auto outer_bus = kstd::make_shared<controller_bus>("stacking_test_controller_bus");
 
diff --git a/kernel/kapi/devices/driver_registry.tests.cpp b/kernel/kapi/devices/driver_registry.tests.cpp
index 02f5065f..7b08799c 100644
--- a/kernel/kapi/devices/driver_registry.tests.cpp
+++ b/kernel/kapi/devices/driver_registry.tests.cpp
@@ -40,7 +40,7 @@ namespace
     {
       ++*match_calls;
 
-      auto const * identification = driver.facet<test_claim>();
+      auto const identification = driver.facet<test_claim>();
       if (!identification)
       {
         return kstd::failure(kapi::devices::driver_match_errc::no_match);
@@ -107,11 +107,11 @@ namespace
     mutable unsigned probe_calls;
 
   protected:
-    auto query_facet(kapi::capabilities::facet_id facet) -> void * override
+    auto query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void> override
     {
       if (facet == test_claim::id)
       {
-        return static_cast<test_claim *>(this);
+        return kstd::make_observer<test_claim>(this);
       }
 
       return kapi::devices::driver::query_facet(facet);
@@ -178,7 +178,7 @@ SCENARIO("Driver registry picks the highest-priority match", "[devices][driver_r
       {
         auto dev = kapi::devices::device_registry::get().find("driver_registry_priority_device");
         REQUIRE(dev != nullptr);
-        REQUIRE(dev->bound_driver() == high_priority.get());
+        REQUIRE(dev->bound_driver() == high_priority);
       }
     }
   }
@@ -203,7 +203,7 @@ SCENARIO("Driver registry breaks ties by registration order", "[devices][driver_
       {
         auto dev = kapi::devices::device_registry::get().find("driver_registry_tie_device");
         REQUIRE(dev != nullptr);
-        REQUIRE(dev->bound_driver() == registered_first.get());
+        REQUIRE(dev->bound_driver() == registered_first);
       }
     }
   }
@@ -255,7 +255,7 @@ SCENARIO("Driver registry leaves bound driver bound, even if better driver arriv
           auto dev = kapi::devices::device_registry::get().find("driver_probe_failure_device");
           REQUIRE(dev != nullptr);
           REQUIRE(dev->state() == kapi::devices::state::bound);
-          REQUIRE(dev->bound_driver() == lower.get());
+          REQUIRE(dev->bound_driver() == lower);
         }
       }
     }
diff --git a/kernel/kapi/devices/facet_registry.cpp b/kernel/kapi/devices/facet_registry.cpp
index 2974c71e..f2f5d03b 100644
--- a/kernel/kapi/devices/facet_registry.cpp
+++ b/kernel/kapi/devices/facet_registry.cpp
@@ -46,7 +46,7 @@ namespace kapi::devices
   }
 
   auto facet_registry::do_publish(kstd::shared_ptr<device> device, kstd::string name, kapi::capabilities::facet_id id,
-                                  void * facet) -> kstd::result<void>
+                                  kstd::observer_ptr<void> facet) -> kstd::result<void>
   {
     auto published = std::optional<entry>{};
 
@@ -169,7 +169,7 @@ namespace kapi::devices
     return filtered;
   }
 
-  auto facet_registry::resolve(kapi::capabilities::facet_id facet, std::string_view name) -> void *
+  auto facet_registry::resolve(kapi::capabilities::facet_id facet, std::string_view name) -> kstd::observer_ptr<void>
   {
     auto found_device = kstd::shared_ptr<device>{};
     {
@@ -193,7 +193,7 @@ namespace kapi::devices
     return resolve(facet, *found_device);
   }
 
-  auto facet_registry::resolve(kapi::capabilities::facet_id id, device & device) -> void *
+  auto facet_registry::resolve(kapi::capabilities::facet_id id, device & device) -> kstd::observer_ptr<void>
   {
     if (auto by_device = device.facet(id))
     {
diff --git a/kernel/kapi/devices/facet_registry.tests.cpp b/kernel/kapi/devices/facet_registry.tests.cpp
index 9396fc6c..f6735f01 100644
--- a/kernel/kapi/devices/facet_registry.tests.cpp
+++ b/kernel/kapi/devices/facet_registry.tests.cpp
@@ -50,15 +50,15 @@ namespace
       return m_value;
     }
 
-    auto query_facet(kapi::capabilities::facet_id facet) -> void * override
+    auto query_facet(kapi::capabilities::facet_id facet) -> kstd::observer_ptr<void> override
     {
       if (facet == probe_device::id)
       {
-        return static_cast<probe_device *>(this);
+        return kstd::make_observer<probe_device>(this);
       }
       if (facet == const_device::id)
       {
-        return m_const_device;
+        return kstd::observer_ptr{m_const_device};
       }
 
       return kapi::devices::device::query_facet(facet);
@@ -143,7 +143,7 @@ SCENARIO("Publishing and finding a device", "[kapi][devices][facet_registry]")
 
       THEN("publishing a free standing second facet for the same device succeeds")
       {
-        REQUIRE(registry.publish(device, "probe0", &free_standing_facet));
+        REQUIRE(registry.publish(device, "probe0", kstd::make_observer(&free_standing_facet)));
       }
 
       AND_WHEN("getting all devices implementing that facet")
@@ -239,7 +239,7 @@ SCENARIO("Publishing and finding a device", "[kapi][devices][facet_registry]")
 
     THEN("publishing the facet for the device fails")
     {
-      REQUIRE_FALSE(registry.publish(device, "probe0", &facet));
+      REQUIRE_FALSE(registry.publish(device, "probe0", kstd::make_observer(&facet)));
     }
   }
 }