zephyr: add basic string/mem functions

Author: tylerwhall

src/zephyr/mod.rs

@@ -54,3 +54,15 @@ cfg_if! {
         }
     }
 }
+
+extern {
+    pub fn strlen(cs: *const c_char) -> size_t;
+
+    pub fn memchr(cx: *const c_void, c: c_int, n: size_t) -> *mut c_void;
+    pub fn memcmp(cx: *const c_void, ct: *const c_void, n: size_t) -> c_int;
+    pub fn memcpy(dest: *mut c_void, src: *const c_void,
+                  n: size_t) -> *mut c_void;
+    pub fn memmove(dest: *mut c_void, src: *const c_void,
+                   n: size_t) -> *mut c_void;
+    pub fn memset(dest: *mut c_void, c: c_int, n: size_t) -> *mut c_void;
+}