fix

Makefile

@@ -5,8 +5,8 @@ BUILDDIR = build
 SRC := $(wildcard $(SRCDIR)/**/*.c)
 OBJ := $(patsubst $(SRCDIR)/%.c,$(OBJDIR)/%.o,$(SRC))
 
-CC = gcc
-CFLAGS = -iquoteheaders -c
+CC = i386-elf-gcc
+CFLAGS = -std=gnu99 -ffreestanding -O2 -Wall -Wextra -iquoteheaders -c
 
 AR = ar
 ARFLAGS = 

src/kprint/kvprintf.c

@@ -18,6 +18,7 @@ static int print_flag(char flag, va_list ap)
 		case 's':
 			return terminal_writestring(va_arg(ap, char *));
 	}
+	return 0;
 }
 
 int kvprintf(int level, const char *restrict format, va_list ap)

src/terminal/terminal.c

@@ -1,4 +1,5 @@
-#include "../../headers/terminal.h"
+#include "terminal.h"
+#include "string.h"
 
 #include <stdbool.h>
 #include <stddef.h>
@@ -14,14 +15,6 @@ static inline uint16_t vga_entry(unsigned char uc, uint8_t color)
 	return (uint16_t) uc | (uint16_t) color << 8;
 }
 
-size_t strlen(const char* str) 
-{
-	size_t len = 0;
-	while (str[len])
-		len++;
-	return len;
-}
-
 static const size_t VGA_WIDTH = 80;
 static const size_t VGA_HEIGHT = 25;
 
@@ -81,17 +74,20 @@ int terminal_writestring(const char* data)
     return len;
 }
 
-int terminal_writelong(long number)
+int terminal_writelong(long n)
 {
-    unsigned long number2 = number;
-
-    if (number < 0) {
-        terminal_putchar('-');
-        number2 = -number;
-    }
-    else {
-        if (number2 > 9)
-            terminal_writelong(number2 / 10);          
-        terminal_putchar(number2 % 10);
-    }
+	long div = 10;
+	int rv = 0;
+	if (n < 0) {
+		rv += terminal_putchar('-');
+		n *= -1;
+	}
+	div = 1;
+	while (div <= n / 10)
+		div *= 10;
+	while (div > 0) {
+		rv += terminal_putchar('0' + n / div % 10);
+		div /= 10;
+	}
+	return rv;
 }