PMM::alloc now dies with a BSOD instead of returning an invalid value. Adds stub of scheduler driver.

prototypes/base/include/driver/scheduler.hpp

@@ -0,0 +1,34 @@
+#pragma once
+
+#include "base.hpp"
+#include "cpustate.hpp"
+#include "pointer.hpp"
+
+namespace driver
+{
+	class Task
+	{
+	private:
+		physical_t stackBottom;
+		CpuState *cpu;
+	public:
+		Task();
+		Task(const Task &) = delete;
+		Task(Task &&) = delete;
+		~Task();
+	};
+
+	class Scheduler : 
+		public Driver
+	{
+	private:
+		static Scheduler *current;
+		static void dispatch(CpuState *cpu);
+		
+		void next(CpuState *cpu);
+	public:
+		Scheduler();
+		
+		void install() override;
+	};
+}

prototypes/base/include/errors.hpp

@@ -6,4 +6,5 @@ enum class Error
   OutOfMemory = 1,
   UnhandledException = 2,
 	UnhandledInterrupt = 3,
+	DriverAlreadyInstalled = 4,
 };

prototypes/base/include/pmm.hpp

@@ -22,9 +22,9 @@ public:
 
   /**
    * Allocates a single page.
-   * @param success This boolean will contain true if the allocation was successful.
+   * @remarks This method will either return a valid value or die with a BSOD if out of memory.
    */
-  static physical_t alloc(bool &success);
+  static physical_t alloc();
 
   /**
    * Frees a given page by pointer.

prototypes/base/include/pointer.hpp

@@ -72,7 +72,7 @@ public:
    * Allow explicit conversion to a raw pointer.
    */
   explicit operator void * () const {
-    return this->ptr;
+    return this->data();
   }
   
   /**

prototypes/base/init.cpp

@@ -11,6 +11,7 @@
 #include "io.hpp"
 
 #include "driver/keyboard.hpp"
+#include "driver/scheduler.hpp"
 
 using namespace multiboot;
 using namespace console_tools;
@@ -22,6 +23,7 @@ extern dummy kernelStartMarker;
 extern dummy kernelEndMarker;
 
 driver::Keyboard keyboardDriver;
+driver::Scheduler scheduler;
 
 void timer(CpuState *cpu)
 {
@@ -94,7 +96,9 @@ extern "C" void init(Structure const & data)
 	IDT::initialize();
 	
 	IDT::interrupt(0x20) = Interrupt(timer);
+	
 	keyboardDriver.install();
+	scheduler.install();
 	
 	Console::main << "Interrupts set up.\n";
 	

prototypes/base/src/pmm.cpp

@@ -1,6 +1,7 @@
 #include <inttypes.h>
 #include <stddef.h>
 #include "pmm.hpp"
+#include "bsod.hpp"
 
 /**
  * Number stored of pages in the bitmap
@@ -53,7 +54,7 @@ void PMM::markUsed(physical_t page)
   bitmap[idx] &= ~(1<<bit);
 }
 
-physical_t PMM::alloc(bool &success)
+physical_t PMM::alloc()
 {
   for(uint32_t idx = 0; idx < BitmapLength; idx++) {
     // fast skip when no bit is set
@@ -73,13 +74,10 @@ physical_t PMM::alloc(bool &success)
       uint32_t pageId = 32 * idx + bit;
       uint32_t ptr = 4096 * pageId;
       
-      success = true;
-      
       return physical_t(ptr);
     }
   }
-  // Do something here!
-  success = false;
+  BSOD::die(Error::OutOfMemory, "Out of physical memory!");
 	return physical_t::invalid;
 }
 

prototypes/base/src/scheduler.cpp

@@ -0,0 +1,50 @@
+#include "driver/scheduler.hpp"
+#include "bsod.hpp"
+#include "pmm.hpp"
+
+namespace driver
+{
+	Scheduler * Scheduler::current = nullptr;
+
+	Scheduler::Scheduler()
+	{
+		
+	}
+
+	void Scheduler::install()
+	{
+		if(Scheduler::current != nullptr) {
+			BSOD::die(Error::DriverAlreadyInstalled, "The scheduler is already installed.");
+		}
+		Scheduler::current = this;
+		
+		
+	}
+
+	void Scheduler::next(CpuState *cpu)
+	{
+	
+	}
+	
+	void Scheduler::dispatch(CpuState *cpu)
+	{
+		if(Scheduler::current != nullptr) {
+			Scheduler::current->next(cpu);
+		} else {
+			
+		}
+	}
+	
+	
+	
+	Task::Task() :
+		stackBottom(PMM::alloc()), cpu(nullptr)
+	{
+		
+	}
+	
+	Task::~Task()
+	{
+		PMM::free(this->stackBottom);
+	}
+}