Simple VFS layer

kernel/hal/hal.h

@@ -11,6 +11,9 @@ void hal_intr_disable(void);
 void hal_intr_enable(void);
 void *hal_memset(void *p, int c, size_t n);
 void *hal_memcpy(void *dst, const void *src, size_t n);
+size_t hal_strlen(char *s);
+int hal_memcmp(const void *s1, const void *s2, int len);
+
 
 #if defined(__x86_64__)
 # define HAL_PAGE_SIZE 0x1000

kernel/hal/util.c

@@ -14,3 +14,34 @@ void *hal_memcpy(void *dst, const void *src, size_t n) {
   for (size_t i = 0; i < n; i++) a[i] = b[i];
   return dst;
 }
+
+size_t hal_strlen(char *s) {
+  char *s2;
+  for (s2 = s; *s2; ++s2);
+  return (s2 - s);
+}
+
+// https://aticleworld.com/memcmp-in-c/
+int hal_memcmp(const void *s1, const void *s2, int len)
+{
+    unsigned char *p = s1;
+    unsigned char *q = s2;
+    int charCompareStatus = 0;
+    //If both pointer pointing same memory block
+    if (s1 == s2)
+    {
+        return charCompareStatus;
+    }
+    while (len > 0)
+    {
+        if (*p != *q)
+        {  //compare the mismatching character
+            charCompareStatus = (*p >*q)?1:-1;
+            break;
+        }
+        len--;
+        p++;
+        q++;
+    }
+    return charCompareStatus;
+}