[hackers] [st] fix regression by selecting clipboard text || Hiltjo Posthuma

[git]

commit f4020b2cc4fe45c9e8bfe47fc73deccd867cf9de
Author:     Hiltjo Posthuma <hil...@codemadness.org>
AuthorDate: Tue Mar 20 21:25:30 2018 +0100
Commit:     Hiltjo Posthuma <hil...@codemadness.org>
CommitDate: Tue Mar 20 21:25:30 2018 +0100

    fix regression by selecting clipboard text
    
    "restore the old behaviour that the primary doesn't get deleted by a simple
    left click"
    
    Patch by Daniel Tameling <tamelingdan...@gmail.com>, thanks!

diff --git a/x.c b/x.c
index 12bc86b..c343ba2 100644
--- a/x.c
+++ b/x.c
@@ -618,6 +618,9 @@ selrequest(XEvent *e)
 void
 setsel(char *str, Time t)
 {
+       if (!str)
+               return;
+
        free(xsel.primary);
        xsel.primary = str;