[????] BUILD 0.1.1.50 DATE 9/20/2011 AT 12:43 PM

====================================================
Mainly changed: Tasking
+ Implemented multitasking
+ Switching works
? TODO: Fix other not working tasking routines

Kernel/debug/logger.c

@@ -118,3 +118,9 @@ int32 LogWrite (uint8 error, string device, string format, ...)
 	ConsoleCursorUpdateHardware();
 	return i;
 }
+
+void LogAssert (int32 condition, string file, int32 line)
+{
+	if (!condition)
+		Panic("Assert", "Assertion failed in file %s line %d.\n", file, line);
+}

Kernel/hal/clock/clock.c

@@ -6,9 +6,9 @@
 volatile TimeSystem _internal_time;
 uint32 _internal_frequency_hz;
 
-extern void TaskSwitch ();
+extern void TaskSwitch (_RegsStack32* regs);
 
-void TimeHandler(_RegsStack32* UNUSED(r))
+void TimeHandler(_RegsStack32* r)
 {
 	if (_internal_frequency_hz == 0) return;
 
@@ -19,5 +19,5 @@ void TimeHandler(_RegsStack32* UNUSED(r))
 		_internal_time.Time-=MILISECONDS_IN_DAY;
 	}
 
-	TaskSwitch();
+	TaskSwitch(r);
 }

Kernel/hal/crash.c

@@ -70,8 +70,8 @@ void CrashMessage(_RegsStack32 *r)
 	ConsoleCursorGoto(c); ConsoleWrite("eflags=0x%x", r->eflags);
 	ConsoleCursorGoto(d); ConsoleWrite("useresp=0x%x\n", r->useresp);
 
-	ConsoleCursorGoto(a); ConsoleWrite("gs=0x%x", r->ss);
-	ConsoleCursorGoto(b); ConsoleWrite("fs=0x%x", r->int_no);
+	ConsoleCursorGoto(a); ConsoleWrite("ss=0x%x", r->ss);
+	ConsoleCursorGoto(b); ConsoleWrite("int_no=0x%x", r->int_no);
 	ConsoleCursorGoto(c); ConsoleWrite("err_code=0x%x", r->err_code);
 
 	// Useful info about page fault

Kernel/include/debugio.h

@@ -65,10 +65,12 @@ extern void ConsoleMain();
 // External test routines
 extern void SystemPanic();
 extern int32 LogWrite (uint8 error, string device, string format, ...);
+extern void LogAssert (int32 condition, string file, int32 line);
 
 // Debug print
 #define Log(dev, ...) { LogWrite(0, dev, __VA_ARGS__); }
 #define Error(dev, ...) { LogWrite(1, dev, __VA_ARGS__); }
 #define Panic(dev, ...) { LogWrite(1, dev, __VA_ARGS__); SystemPanic();  }
+#define Assert(c) { LogAssert(c, __FILE__, __LINE__); }
 
 #endif

Kernel/include/tasking.h

@@ -13,10 +13,11 @@
 
 typedef struct _Task {
 	uint32 Pid;
-	uint32 Esp, Ebp; // Stack
+	uint32 Eip, Esp, Ebp;
 	PageDirectory* Pd;
 	uint32 StackLowerBase;
 	uint32 StackUpperBase;
+	uint8 Initialized;
 	struct _Task* Next;
 } Task;
 

Kernel/include/version.h

@@ -1 +1 @@
-#define OS_BUILD "0.1.1.19"
+#define OS_BUILD "0.1.1.50"

Kernel/tasking/tasking-asm.asm

@@ -0,0 +1,7 @@
+; tasking.asm
+bits 32
+
+global TaskReadEip
+TaskReadEip:
+	pop eax
+	jmp eax

Kernel/tasking/tasking-multi.c

@@ -7,27 +7,41 @@
 
 #include <tasking.h>
 #include <memory-add.h>
+#include <stdio.h>
 
 Task* TaskList;
 Task* CurrentTask;
 uint32 NextPid = 1;
 
-void TaskSwitch ()
+void TaskSwitch (_RegsStack32* regs)
 {
+	MagicBreakpoint();
+
 	if (!TaskList) return;
 
+	uint32 eip = TaskReadEip();
+	if (eip == 0xABCDEF) return;
+
 	// Save context
-	asm volatile ("mov %%esp, %0" : "=r"(CurrentTask->Esp));	// Stack pointer
-	asm volatile ("mov %%ebp, %0" : "=r"(CurrentTask->Ebp)); // Base pointer
-	CurrentTask->Pd = CurrentDirectory;
+	asm volatile ("mov %%esp, %0" : "=r"(CurrentTask->Esp));
+	asm volatile ("mov %%ebp, %0" : "=r"(CurrentTask->Ebp));
+	CurrentTask->Eip = eip;
 
 	// Next task
 	CurrentTask = (!CurrentTask->Next) ? TaskList : CurrentTask->Next ;
 
 	// Switch context
 	PagingSwitchDirectory(CurrentTask->Pd);
-	asm volatile ("mov %0, %%esp" : : "r"(CurrentTask->Esp));	// Stack pointer
-	asm volatile ("mov %0, %%ebp" : : "r"(CurrentTask->Ebp)); // Base pointer
+
+	// Prepare for jump
+	asm volatile (""
+			"mov %0, %%ebp; "
+			"mov %1, %%esp; "
+			"mov %2, %%ecx; "
+			"mov $0xABCDEF, %%eax; "
+			"jmp *%%ecx; "
+			: : "r"(CurrentTask->Ebp), "r"(CurrentTask->Esp), "r"(CurrentTask->Eip)
+			: "eax", "ecx");
 }
 
 // Fallback for new tasks
@@ -64,25 +78,16 @@ void TaskCreate (void (*func)())
 	t->Pid = NextPid++;
 
 	// Set up stack
-	*(uint32 *) (t->StackUpperBase - 0x4) = (uint32) TaskEnd; // Fallback function
-	t->Ebp = (uint32) t->StackUpperBase;
+	/*memset(&t->Regs, 0, sizeof(_RegsStack32));
+	t->Regs.ebp = t->StackUpperBase;
+	t->Regs.esp = (t->StackUpperBase - 0x4 - sizeof(_RegsStack32));
+	t->Regs.useresp = t->StackUpperBase - 0x4;
+	t->Regs.eip = (uint32) func;
+	*(uint32 *) (t->Regs.esp) = (uint32) TaskEnd; // Fallback function
+	t->Initialized = 0;
 
-	_RegsStack32* regs = (_RegsStack32*) (t->StackUpperBase - 0x4 - sizeof(_RegsStack32));
-
-	asm volatile ("mov %%ss, %0" : "=r" (regs->ss));
-	asm volatile ("mov %%cs, %0" : "=r" (regs->cs));
-	asm volatile ("pushf; pop %0" : "=r" (regs->eflags));
-	asm volatile ("mov %%esi, %0" : "=r" (regs->esi));
-	asm volatile ("mov %%edi, %0" : "=r" (regs->edi));
-	asm volatile ("mov %%gs, %0" : "=r" (regs->gs));
-	asm volatile ("mov %%fs, %0" : "=r" (regs->fs));
-	asm volatile ("mov %%es, %0" : "=r" (regs->es));
-	asm volatile ("mov %%ds, %0" : "=r" (regs->ds));
-	regs->eax = regs->ebx = regs->ecx = regs->edx = 0;
-	regs->eip = (uint32)func;
-	regs->useresp = t->StackUpperBase-0x4;
-	regs->esp = t->StackUpperBase - 40;
-	regs->ebp = t->Ebp = t->StackUpperBase;
+	// Read eflags
+	asm volatile ("pushf; pop %0" : "=r"(t->Regs.eflags));*/
 
 	// Add the task to the list
 	Task* last = TaskList;
@@ -96,7 +101,6 @@ void TaskInitialize()
 
 	t->Pid = NextPid++;
 	t->Pd = KernelDirectory;
-	t->Esp = t->Ebp = 0;
 	t->Next = NULL;
 
 	TaskList = CurrentTask = t;