From 906510c90750b09d5b05914f03f190c14460e03e Mon Sep 17 00:00:00 2001
From: Felix Morgner <felix.morgner@ost.ch>
Date: Sat, 25 Jul 2026 00:29:35 +0200
Subject: chore: hide protocol implementations

---
 kernel/kernel/bus/boot_modules.cpp | 68 ++++++++++++++++++++++----------------
 kernel/kernel/bus/boot_modules.hpp |  7 +---
 2 files changed, 40 insertions(+), 35 deletions(-)

(limited to 'kernel')

diff --git a/kernel/kernel/bus/boot_modules.cpp b/kernel/kernel/bus/boot_modules.cpp
index ac5a2068..069d414f 100644
--- a/kernel/kernel/bus/boot_modules.cpp
+++ b/kernel/kernel/bus/boot_modules.cpp
@@ -11,50 +11,60 @@
 
 namespace kernel::bus
 {
-  auto has_parameter(std::string_view cmdline, std::string_view key, std::string_view value) -> bool
+  namespace
   {
-    for (auto token : std::views::split(cmdline, ' '))
+    auto has_parameter(std::string_view cmdline, std::string_view key, std::string_view value) -> bool
     {
-      auto const text = std::string_view{token};
-      auto const equals = text.find('=');
-      if (equals != std::string_view::npos && text.substr(0, equals) == key && text.substr(equals + 1) == value)
+      for (auto token : std::views::split(cmdline, ' '))
       {
-        return true;
+        auto const text = std::string_view{token};
+        auto const equals = text.find('=');
+        if (equals != std::string_view::npos && text.substr(0, equals) == key && text.substr(equals + 1) == value)
+        {
+          return true;
+        }
       }
+      return false;
     }
-    return false;
-  }
 
-  boot_modules::boot_modules()
-      : kapi::devices::bus{"boot_modules"}
-  {}
+    struct boot_modules_protocol : kapi::devices::bus_protocol
+    {
+      auto enumerate(kapi::devices::bus &) -> void override
+      {
+        // The boot modules virtual bus does not support enumeration.
+      }
 
-  auto boot_modules::enumerate(kapi::devices::bus &) -> void {}
+      [[nodiscard]] auto match(kapi::devices::device const & dev, kapi::devices::driver const & drv) const
+          -> kstd::result<unsigned> override
+      {
+        auto signature = dev.as<kapi::boot_modules::boot_module_signature>();
+        auto claim = drv.as<kapi::boot_modules::boot_module_claim>();
 
-  auto boot_modules::match(kapi::devices::device const & dev, kapi::devices::driver const & drv) const
-      -> kstd::result<unsigned>
-  {
-    auto signature = dev.as<kapi::boot_modules::boot_module_signature>();
-    auto claim = drv.as<kapi::boot_modules::boot_module_claim>();
+        if (!signature || !claim)
+        {
+          return kstd::failure(kapi::devices::driver_match_errc::no_match);
+        }
 
-    if (!signature || !claim)
-    {
-      return kstd::failure(kapi::devices::driver_match_errc::no_match);
-    }
+        auto const [key, value] = claim->parameter();
 
-    auto const [key, value] = claim->parameter();
+        if (!has_parameter(signature->command_line(), key, value))
+        {
+          return kstd::failure(kapi::devices::driver_match_errc::no_match);
+        }
 
-    if (!has_parameter(signature->command_line(), key, value))
-    {
-      return kstd::failure(kapi::devices::driver_match_errc::no_match);
-    }
+        return 0u;
+      }
 
-    return 0u;
-  }
+    } constinit protocol_instance;
+  }  // namespace
+
+  boot_modules::boot_modules()
+      : kapi::devices::bus{"boot_modules"}
+  {}
 
   auto boot_modules::protocol() -> kapi::devices::bus_protocol *
   {
-    return this;
+    return &protocol_instance;
   }
 
 }  // namespace kernel::bus
diff --git a/kernel/kernel/bus/boot_modules.hpp b/kernel/kernel/bus/boot_modules.hpp
index 147cfdf2..c73e0d74 100644
--- a/kernel/kernel/bus/boot_modules.hpp
+++ b/kernel/kernel/bus/boot_modules.hpp
@@ -11,15 +11,10 @@ namespace kernel::bus
   //! The boot modules bus.
   //!
   //! Boot modules used to back devices may be attached to this bus.
-  struct boot_modules final : kapi::devices::bus, kapi::devices::bus_protocol
+  struct boot_modules final : kapi::devices::bus
   {
     boot_modules();
 
-    auto enumerate(kapi::devices::bus & self) -> void override;
-
-    [[nodiscard]] auto match(kapi::devices::device const & dev, kapi::devices::driver const & drv) const
-        -> kstd::result<unsigned> override;
-
     [[nodiscard]] auto protocol() -> kapi::devices::bus_protocol * override;
   };
 
-- 
cgit v1.2.3