* Implemented task changing

it can change task to certain task
* updated INTTOCHARPOINT
* Bumped SectorOS kernel version
* Added new syscalls

Author: Arun007coder

CPU/syscall.cpp

@@ -1,11 +1,21 @@
 #include "syscall.h"
 
 void printf(char*);
+void printfchar(char);
 PowerControl syscontrol;
 
+inline GlobalDescriptorTable gdt;
+void taskA();
+void taskB();
+
+Task tsk1(&gdt, taskA);
+Task tsk2(&gdt, taskB);
+
 SyscallHandler::SyscallHandler(InterruptManager* interruptManager, uint8_t InterruptNumber)
 :InterruptHandler(InterruptNumber  + interruptManager->HardwareInterruptOffset(), interruptManager)
 {
+    taskManager.AddTask(&tsk1);
+    taskManager.AddTask(&tsk2);
 }
 
 SyscallHandler::~SyscallHandler()
@@ -19,14 +29,22 @@ uint32_t SyscallHandler::HandleInterrupt(uint32_t esp)
 
     switch(cpu->eax)
     {
-        case 1: // sys_print
+        case 1: // sys_printf
             printf((char*)cpu->ebx);
             break;
 
-        case 2: // sys_reboot
+        case 2: // sys_printc
+            printfchar((char)cpu->ebx);
+            break;
+
+        case 3: // sys_reboot
             syscontrol.reboot();
             break;
 
+        case 4: // sys_cng_task
+            esp = (uint32_t)taskManager.SwitchTask((int)cpu->ebx, (CPUState*)esp);
+            break;
+
         default:
             break;
     }

CPU/syscall.h

@@ -4,9 +4,11 @@
 #include "../Include/types.h"
 #include "Interrupts.h"
 #include "PowerControl.h"
+#include "../kernel/MultiTask.h"
 
 class SyscallHandler : public InterruptHandler
 {
+    TaskManager taskManager;
 public:
     SyscallHandler(InterruptManager* interruptManager, uint8_t InterruptNumber);
     ~SyscallHandler();

Drivers/Keyboard.cpp

@@ -12,7 +12,7 @@ char* INTTOCHARPOINT(int num);
 void ColourPrint(int type);
 bool txtcolor;
 bool isESPChanged = false;
-GlobalDescriptorTable gdt;
+inline GlobalDescriptorTable gdt;
 void taskA();
 void taskB();
 const void* mb;
@@ -54,10 +54,6 @@ CommandPort(0x64)
     clear_key_buffer();
     isTxtMode = false;
     this->shell = shell;
-    Task task1(&gdt, taskA);
-    Task task2(&gdt, taskB);
-    taskManager.AddTask(&task1);
-    taskManager.AddTask(&task2);
 
     for(int i = 0; i < 30; i++)
     {
@@ -497,10 +493,10 @@ void KeyboardDriver::CommandInterpreter() // SOSH v1.0.3 [SectorOS SHell]. 11 Co
         }
         else if(key_buffer[0] == "t" && key_buffer[1] == "s" && key_buffer[2] == "k")
         {
-            esp1 = (uint32_t)taskManager.Schedule((CPUState*)esp1);
-            printf("esp1 is :"); printHex(esp1); printf("\n");
-            printf("esp2 is :"); printHex(esp2);
-            isESPChanged = true;
+            char* arg1 = key_buffer[4]; 
+            int tsknum = arg1[0] - '0';
+            asm("int $0x80" : : "a" (0x04), "b" (tsknum));
+            //asm("int $0x80" : : "a" (0x05));
         }
         else if (key_buffer[0] == "e" && key_buffer[1] == "x" && key_buffer[2] == "p" && key_buffer[3] == "o" && key_buffer[4] == "r" && key_buffer[5] == "t")
         {

Include/Public_VAR.h

@@ -4,12 +4,12 @@
 inline char* OS_NAME = "SectorOS";
 
 inline char* KERNEL_NAME = "SectorOS";
-inline char* KERNEL_VERSION = "V2.1.6";
-inline char* KERNEL_BUILD = "Build: 2021-12-11";
+inline char* KERNEL_VERSION = "V2.2.1";
+inline char* KERNEL_BUILD = "Build: 2022-01-06";
 inline char* KERNEL_ARCH = "x86";
 
 inline char* SHELL_NAME = "SOSH";
-inline char* SHELL_VER = "V1.1.2";
+inline char* SHELL_VER = "V1.1.3";
 
 // START Environment variables
 inline char* SP[30]; // Shell Prompt

kernel/MultiTask.cpp

@@ -64,4 +64,11 @@ CPUState* TaskManager::Schedule(CPUState* cpustate)
     if(++currentTask >= numTasks)
         currentTask %= numTasks;
     return tasks[currentTask]->cpustate;
+}
+
+CPUState* TaskManager::SwitchTask(int tasknum, CPUState* CSTATE)
+{
+    if(tasknum >= numTasks)
+        return tasks[tasknum]->cpustate;
+    return tasks[tasknum]->cpustate;
 }

kernel/MultiTask.h

@@ -48,6 +48,7 @@ class TaskManager
     TaskManager();
     ~TaskManager();
     bool AddTask(Task* task);
+    CPUState* SwitchTask(int tasknum, CPUState* CSTATE);
     CPUState* Schedule(CPUState* cpustate);
 };