Implement printf

kernel/include/console.hpp

@@ -12,5 +12,6 @@ void k_print(const char* string);
 void k_print(std::size_t number);
 void k_print_line();
 void k_print_line(const char* string);
+void k_printf(const char* fmt, ...);
 
 #endif

kernel/src/console.cpp

@@ -1,4 +1,5 @@
 #include <cstddef>
+#include <cstdarg>
 
 #include "console.hpp"
 #include "types.hpp"
@@ -109,3 +110,28 @@ void wipeout(){
     current_line = 0;
     current_column = 0;
 }
+
+void k_printf(const char* fmt, ...){
+    va_list va;
+    va_start(va, fmt);
+
+    char ch;
+
+    while ((ch=*(fmt++))) {
+        if(ch != '%'){
+            k_print(ch);
+        } else {
+            ch = *(fmt++);
+
+            if(ch == 'd'){
+                auto arg = va_arg(va, std::size_t);
+                k_print(arg);
+            } else if(ch == 's'){
+                auto arg = va_arg(va, const char*);
+                k_print(arg);
+            }
+        }
+    }
+
+    va_end(va);
+}

kernel/src/shell.cpp

@@ -100,9 +100,7 @@ void exec_command(){
         }
     }
 
-    k_print("The command \"");
+    k_printf("The command \"%s\" does not exist\n", current_input);
-    k_print(current_input);
-    k_print("\" does not exist \n");
 }
 
 void clear_command(const char*){