run script: Don't overwrite LD_LIBRARY_PATH and PERL5LIB

This change allows the run scripts of virt-v2v and libguestfs to be chained.
(cherry picked from commit 252ad4aa41c213948e4ee1f01e6c7ff7861f75e3)

diff --git a/run.in b/run.in
index 9388398..7cef715 100755 (executable)
--- a/run.in
+++ b/run.in
@@ -37,9 +37,19 @@ b=@abs_builddir@
 export TMPDIR="$b"
 
 # Set local environment relative to this script.
-export LD_LIBRARY_PATH="$b/src/.libs"
-export LIBGUESTFS_PATH="$b/appliance"
-export PERL5LIB="$b/perl/blib/lib:$b/perl/blib/arch"
+if [ -z "$LD_LIBRARY_PATH" ]; then
+  LD_LIBRARY_PATH="$b/src/.libs"
+else
+  LD_LIBRARY_PATH="$b/src/.libs:$LD_LIBRARY_PATH"
+fi
+if [ -z "$PERL5LIB" ]; then
+  PERL5LIB="$b/perl/blib/lib:$b/perl/blib/arch"
+else
+  PERL5LIB="$b/perl/blib/lib:$b/perl/blib/arch:$PERL5LIB"
+fi
+LIBGUESTFS_PATH="$b/appliance"
+
+export LD_LIBRARY_PATH PERL5LIB LIBGUESTFS_PATH
 
 # Do we have libtool?  If we have it then we can use it to make
 # running valgrind simpler.  However don't depend on it.