syscalls: start adding fork syscall, not done yet

include/paging.h

@@ -40,6 +40,7 @@ void set_page_dir(uint32_t new_page_dir);
 uint32_t phys_to_virt(uint32_t phys);
 uint32_t* create_page_dir();
 void destroy_page_dir(uint32_t* page_dir);
+uint32_t* copy_page_dir(uint32_t* page_dir_virt);
 
 static inline uint32_t virt_to_phys(void* virt) {
     return (uint32_t)virt - 0xC0000000;

include/stdio.h

@@ -14,7 +14,7 @@ int printf(const char* __restrict, ...);
 int putchar(int);
 int puts(const char*);
 
-//#define KATAU_DEBUG
+#define KATAU_DEBUG
 
 #ifdef KATAU_DEBUG
 #define debug_log printf

include/task.h

@@ -17,6 +17,8 @@
 
 #define MAX_OPEN_FILES 32
 
+#define KSTACKSIZE 4096
+
 typedef enum TaskState
 {
     Ready,