The Melon kernel now has support for simple multitasking

1 files changed, 106 insertions, 0 deletions

diff --git a/Source/Kernel/TaskManager/Thread.class.cpp b/Source/Kernel/TaskManager/Thread.class.cpp
new file mode 100644
index 0000000..cc2f569
--- /dev/null
+++ b/Source/Kernel/TaskManager/Thread.class.cpp
@@ -0,0 +1,106 @@
+#include "Thread.class.h"
+#include <TaskManager/Task.ns.h>
+#include <MemoryManager/PageAlloc.ns.h>
+#include <DeviceManager/Time.ns.h>
+
+void runThread(Thread* thread, u32int (*entry_point)()) {
+	asm volatile("sti");
+	thread->run(entry_point);
+}
+
+Thread::Thread() {	//Private constructor, does nothing
+}
+
+Thread::Thread(u32int (*entry_point)(), bool iskernel) {
+	if (iskernel) {
+		m_isKernel = true;
+		u32int tmp;
+		m_kernelStackFrame = (u32int)PageAlloc::alloc(&tmp);
+		m_process = Task::getKernelProcess();
+		setup(entry_point, m_kernelStackFrame + STACKSIZE);
+	} else {
+		m_isKernel = false;
+		m_process = Task::currentProcess;
+		setup(entry_point, m_process->stackAlloc() + STACKSIZE);
+	}
+}
+
+Thread::Thread(Process* process, u32int (*entry_point)()) {
+	m_isKernel = false;
+	m_process = process;
+	setup(entry_point, m_process->stackAlloc() + STACKSIZE);
+}
+
+Thread::~Thread() {
+	if (m_isKernel)
+		PageAlloc::free((void*)m_kernelStackFrame);
+	Task::unregisterThread(this);
+	//Don't unregister thread in process, it has probably already been done
+}
+
+void Thread::setup(u32int (*entry_point)(), u32int esp) {
+	//Pass function parameters for runThread()
+	u32int *stack = (u32int*)esp;
+	stack--;
+	*stack = (u32int)entry_point;	//Push entry point (function parameter)
+	stack--;
+	*stack = (u32int)this;	//Push object pointer
+	stack--;
+	*stack = 0;	//Null return address
+	m_esp = (u32int)stack;
+	m_ebp = m_esp + 8;
+	m_eip = (u32int)runThread;
+
+	m_state = T_RUNNING;
+	m_process->registerThread(this);
+	Task::registerThread(this);
+}
+
+void Thread::finish(u32int errcode) {
+	//Needs not set m_state to a finished state, either :
+	// - thread is unregistered from process and everywhere
+	// - errcode is an exception or this is main thread, process exits
+	m_process->threadFinishes(this, errcode);
+} 
+
+void Thread::run(u32int (*entry_point)()) {
+	u32int ret = entry_point();	//Run !
+	finish(ret);
+}
+
+void Thread::setState(u32int esp, u32int ebp, u32int eip) {
+	m_esp = esp;
+	m_ebp = ebp;
+	m_eip = eip;
+}
+
+u32int Thread::getEsp() { return m_esp; }
+u32int Thread::getEbp() { return m_ebp; }
+u32int Thread::getEip() { return m_eip; }
+
+Process* Thread::getProcess() { return m_process; }
+
+void Thread::sleep(u32int msecs) {
+	m_state = T_SLEEPING;
+	waitfor.m_time = Time::time() + msecs;
+
+	Task::triggerSwitch();
+}
+
+void Thread::waitIRQ(u8int irq) {
+	if (m_process->m_uid != 0) return;
+
+	m_state = T_IRQWAIT;
+	waitfor.m_irq = irq;
+
+	Task::triggerSwitch();
+}
+
+bool Thread::runnable() {
+	if (m_state == T_RUNNING) return true;
+	if (m_state == T_SLEEPING and Time::time() >= waitfor.m_time) {
+		m_state = T_RUNNING;
+		return true;
+	}
+	return false;
+}