artec_eplus48u.c: fix HOME env bug #315071 (from Jörg Frings-Fürst)

ChangeLog

@@ -1,3 +1,6 @@
+2015-19-08 m. allan noah <kitno455 at gmail dot com>
+	* backend/artec_eplus48u.c: fix HOME env bug #315071 (from Jörg Frings-Fürst)
+
 2015-09-03 Rolf Bensch <rolf at bensch hyphen online dot de>
 	* backend/pixma_mp810.c: Canon Pixma MP990 needs specific reordering pixels
 	  for 4800 dpi, patch from Guillaume Courtois.

backend/artec_eplus48u.c

@@ -67,7 +67,7 @@ Updates (C) 2001 by Henning Meier-Geinitz.
    whether to permit this exception to apply to your modifications.
    If you do not wish that, delete this exception notice.  */
 
-#define BUILD 11
+#define BUILD 12
 
 #include "../include/sane/config.h"
 
@@ -3580,6 +3580,14 @@ load_calibration_data (Artec48U_Scanner * s)
 
   s->calibrated = SANE_FALSE;
   path[0] = 0;
+
+  /* return SANE_STATUS_INVAL if HOME environment variable is not set */
+  if (getenv ("HOME") == NULL)
+  {
+    XDBG ((1, "Environment variable HOME not set\n"));
+    return SANE_STATUS_INVAL;
+  }
+
   if (strlen (getenv ("HOME")) < (PATH_MAX - 1))
     strcat (path, getenv ("HOME"));
   else
@@ -3690,6 +3698,14 @@ save_calibration_data (Artec48U_Scanner * s)
   mode_t mode = S_IRUSR | S_IWUSR;
 
   path[0] = 0;
+
+  /* return SANE_STATUS_INVAL if HOME environment variable is not set */
+  if (getenv ("HOME") == NULL)
+  {
+    XDBG ((1, "Environment variable HOME not set\n"));
+    return SANE_STATUS_INVAL;
+  }
+
   if (strlen (getenv ("HOME")) < (PATH_MAX - 1))
     strcat (path, getenv ("HOME"));
   else