From f8caa49f003803856a0db4febd1bbb334ae2a26e Mon Sep 17 00:00:00 2001
From: "Nicolas B. Pierron" <nicolas.b.pierron@gmail.com>
Date: Sun, 23 Aug 2015 13:54:34 +0200
Subject: [PATCH] sane-config: Merge /etc/sane.d/dll.conf content.

---
 pkgs/applications/graphics/sane/config.nix | 28 +++++++++++++++-------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/pkgs/applications/graphics/sane/config.nix b/pkgs/applications/graphics/sane/config.nix
index fc1cd81ebc6..26f1eddbed6 100644
--- a/pkgs/applications/graphics/sane/config.nix
+++ b/pkgs/applications/graphics/sane/config.nix
@@ -4,17 +4,27 @@
 
 with stdenv.lib;
 let installSanePath = path: ''
-      find "${path}/lib/sane" -not -type d -maxdepth 1 | while read backend; do
-        ln -s $backend $out/lib/sane/$(basename $backend)
-      done
+      if test -e "${path}/lib/sane"; then
+        find "${path}/lib/sane" -not -type d -maxdepth 1 | while read backend; do
+          ln -s $backend $out/lib/sane/$(basename $backend)
+        done
+      fi
 
-      find "${path}/etc/sane.d" -not -type d -maxdepth 1 | while read conf; do
-        ln -s $conf $out/etc/sane.d/$(basename $conf)
-      done
+      if test -e "${path}/etc/sane.d"; then
+        find "${path}/etc/sane.d" -not -type d -maxdepth 1 | while read conf; do
+          if test $(basename $conf) = "dll.conf"; then
+            cat $conf >> $out/etc/sane.d/dll.conf
+          else
+            ln -s $conf $out/etc/sane.d/$(basename $conf)
+          fi
+        done
+      fi
 
-      find "${path}/etc/sane.d/dll.d" -not -type d -maxdepth 1 | while read conf; do
-        ln -s $conf $out/etc/sane.d/dll.d/$(basename $conf)
-      done
+      if test -e "${path}/etc/sane.d/dll.d"; then
+        find "${path}/etc/sane.d/dll.d" -not -type d -maxdepth 1 | while read conf; do
+          ln -s $conf $out/etc/sane.d/dll.d/$(basename $conf)
+        done
+      fi
     '';
 in
 stdenv.mkDerivation {