use stdint

include/kernel/vga.h

@@ -12,6 +12,6 @@ struct vga_char {
 #define VGA_MEM ((struct vga_char*)0xb8000)
 
 void vga_put_char(struct vga_char* c);
-void vga_printk(const char* str, uint8_t color);
+void vga_printk(const int8_t* str, uint8_t color);
 
 #endif // _KERNEL_VGA_H_

src/kernel/vga.c

@@ -1,4 +1,6 @@
 #define _KERNEL_VGA_C_
+#include <types/stdint.h>
+
 #include <kernel/vga.h>
 
 static struct vga_char* p_vga_head = VGA_MEM;
@@ -9,7 +11,7 @@ void vga_put_char(struct vga_char* c)
     ++p_vga_head;
 }
 
-void vga_printk(const char* str, uint8_t color)
+void vga_printk(const int8_t* str, uint8_t color)
 {
     struct vga_char s_c;
     s_c.color = color;