kernel: Refactor default stdout to be per-platform

Author: fwsGonzo

api/kernel/os.hpp

@@ -138,11 +138,15 @@ class OS {
    */
   static void add_stdout(print_func func);
   /**
-   *  Add "default" serial port output
+   *  Add stdout handler that calls OS::default_stdout
   **/
-  static void add_stdout_default_serial();
+  static void add_default_stdout();
 
-  static void add_stdout_solo5();
+  /**
+   *  The default output method preferred by each platform
+   *  Directly writes the string to its output mechanism
+   **/
+  static void default_stdout(const char*, size_t);
 
   /** Memory page helpers */
   static constexpr uint32_t page_size() noexcept {

src/drivers/silent.cpp

@@ -25,6 +25,6 @@ void default_stdout_handlers()
   [] (const char* str, size_t len)
   {
     if (OS::is_booted() || OS::is_panicking())
-      kprintf("%.*s", len, str);
+        OS::default_stdout(str, len);
   });
 }

src/kernel/os.cpp

@@ -65,7 +65,6 @@ std::string OS::cmdline{Service::binary_name()};
 // stdout redirection
 using Print_vec = fixedvector<OS::print_func, 8>;
 static Print_vec os_print_handlers(Fixedvector_Init::UNINIT);
-extern void default_stdout_handlers();
 
 // Plugins
 OS::Plugin_vec OS::plugins_(Fixedvector_Init::UNINIT);
@@ -102,17 +101,17 @@ void OS::add_stdout(OS::print_func func)
 {
   os_print_handlers.add(func);
 }
-void OS::add_stdout_default_serial()
+void OS::add_default_stdout()
 {
   add_stdout(
   [] (const char* str, const size_t len) {
-    kprintf("%.*s", static_cast<int>(len), str);
+      OS::default_stdout(str, len);
   });
 }
 __attribute__ ((weak))
 void default_stdout_handlers()
 {
-  OS::add_stdout_default_serial();
+  OS::add_default_stdout();
 }
 size_t OS::print(const char* str, const size_t len)
 {

src/platform/x86_nano/platform.cpp

@@ -16,11 +16,6 @@ void __arch_poweroff()
   __builtin_unreachable();
 }
 
-void default_stdout_handlers()
-{
-  OS::add_stdout_default_serial();
-}
-
 void __platform_init(){
   // FIXME: set up minimal CPU exception handlers
   // TODO: set up minimal CPU exception handlers

src/platform/x86_pc/os.cpp

@@ -226,5 +226,3 @@ void OS::event_loop()
   extern void __arch_poweroff();
   __arch_poweroff();
 }
-
-

src/platform/x86_solo5/kernel_start.cpp

@@ -9,18 +9,12 @@ extern "C" {
 #include <solo5.h>
 }
 
-extern  void solo5_stdout_handlers();
-extern  void __platform_init();
+extern void __platform_init();
+extern void default_stdout_handlers();
 
 char cmdline[256];
 uintptr_t mem_size;
 
-__attribute__ ((weak))
-void solo5_stdout_handlers()
-{
-  OS::add_stdout_solo5();
-}
-
 extern "C" {
   void __init_sanity_checks();
   void kernel_sanity_checks();
@@ -38,7 +32,7 @@ extern "C" {
   void (*current_eoi_mechanism)();
   void (*current_intr_handler)();
   void (*cpu_sampling_irq_handler)();
- 
+
 
   void kernel_start()
   {
@@ -68,7 +62,7 @@ extern "C" {
     _init_syscalls();
 
     //Initialize stdout handlers
-    solo5_stdout_handlers();
+    default_stdout_handlers();
 
     // Call global ctors
     __libc_init_array();

src/platform/x86_solo5/os.cpp

@@ -70,12 +70,9 @@ int64_t OS::micros_since_boot() noexcept {
   return uptime() / 1000;
 }
 
-void OS::add_stdout_solo5()
+void OS::default_stdout(const char* str, const size_t len)
 {
-  add_stdout(
-  [] (const char* str, const size_t len) {
-    solo5_console_write(str, len);
-  });
+  solo5_console_write(str, len);
 }
 
 void OS::start(char* _cmdline, uintptr_t mem_size)

test/lest_util/os_mock.cpp

@@ -75,6 +75,8 @@ Timers::id_t Timers::periodic(duration_t, duration_t, handler_t) {
 #include <kernel/os.hpp>
 void OS::start(unsigned, unsigned) {
 }
+void OS::default_stdout(const char*, size_t) {
+}
 void OS::event_loop() {
 }
 void OS::block() {