Making sure filename is null terminated string

Added file_handle validation

src/util/cstr_helper.c

@@ -2,21 +2,33 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "cstr_helper.h"
 
-int copy_cstr(const char *source, char **destination, size_t *size)
+
+int copy_cstr(const char *source, char **dest)
 // Determines length, allocates memory, and returns a null terminated copy
 // Be Aware: caller is responsible for freeing memory
 {
     size_t len;
 
     len = strlen(source);
-    *destination = (char *) calloc(len + 1, sizeof(char));
+    *dest = (char *) calloc((len + 1), sizeof(char));
 
-    if (*destination == NULL)
+    if (*dest == NULL)
         return -1;
     else {
-        strncpy(*destination, source, len);
-        *size = len + 1;
+        strncpy(*dest, source, (len + 1));
+		strncat(*dest, "\0", 1);
     }
     return 0;
 }
+
+
+bool isnullterm_cstr(const char *source)
+{
+	if (strchr(source, '\0'))
+		return true;
+	else
+		return false;
+
+}