1 files changed, 7 insertions, 2 deletions
diff --git a/src/libs/string.hpp b/src/libs/string.hpp
index 305b9a8..a7dce0a 100644
--- a/src/libs/string.hpp
+++ b/src/libs/string.hpp
@@ -5,7 +5,7 @@
 /**
  * Copy data byte per byte from src to dst
  */
-void memcpy(void *src, void *dst, int size);
+void memcpy(void *src, void *dst, u32 size);
 
 /**
  * Convert int to char array
@@ -20,4 +20,9 @@ void itoh(u64 i, char *a);
 /**
  * Length of a char*
  */
-int strlen(char *s);
+u32 strlen(char *s);
+
+/**
+ * Substr
+ */
+void substr(u32 s, u32 e, char *src, char *dst);