hook_arg2 = "";
        }
 
-       s->fp = fopen(git_path(commit_editmsg), "w");
+       s->fp = fopen_for_writing(git_path(commit_editmsg));
        if (s->fp == NULL)
                die_errno(_("could not open '%s'"), git_path(commit_editmsg));
 
                if (fp == NULL)
                        die_errno(_("could not open '%s' for reading"),
                                  git_path_merge_head());
-               while (strbuf_getline(&m, fp, '\n') != EOF) {
+               while (strbuf_getline_lf(&m, fp) != EOF) {
                        struct commit *parent;
 
                        parent = get_merge_parent(m.buf);