From 294a7f1c0358a15037d39fe20b4ba29e0d16faf1 Mon Sep 17 00:00:00 2001
From: Carlos Maddela <e7appew@gmail.com>
Date: Wed, 29 Mar 2017 21:15:31 +1100
Subject: [PATCH] Do not modify HOME environment variable.

https://github.com/kfish/xsel/pull/15 introduces some side-effects.
The HOME environment variable is modified, and more likely than not,
it overflows the string's buffer.

Make sure we return the string in memory we've allocated ourselves
to fix this.
---
 xsel.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/xsel.c b/xsel.c
index 685bdd6..54e7c64 100644
--- a/xsel.c
+++ b/xsel.c
@@ -343,12 +343,21 @@ static char *
 get_xdg_cache_home (void)
 {
   char * cachedir;
+  char * homedir;
+  static const char * slashbasename = "/.cache";
 
   if ((cachedir = getenv ("XDG_CACHE_HOME")) == NULL) {
-    cachedir = strcat(getenv ("HOME"), "/.cache");
+    if ((homedir = getenv ("HOME")) == NULL) {
+      exit_err ("no HOME directory");
+    }
+    cachedir = xs_malloc (strlen (homedir) + strlen (slashbasename) + 1);
+    strcpy (cachedir, homedir);
+    strcat (cachedir, slashbasename);
+  } else {
+    cachedir = _xs_strdup (cachedir);
   }
 
-  mkdir(cachedir, S_IRWXU|S_IRGRP|S_IXGRP);
+  mkdir (cachedir, S_IRWXU|S_IRGRP|S_IXGRP);
 
   return cachedir;
 }
@@ -515,6 +524,8 @@ become_daemon (void)
   }
 
   set_daemon_timeout ();
+
+  free (cachedir);
 }
 
 /*