ruby interface: raise an exception if we couldn't open a file

diff --git a/lib/ruby/gfx.c b/lib/ruby/gfx.c
index 661d8ef..958ce40 100644 (file)
--- a/lib/ruby/gfx.c
+++ b/lib/ruby/gfx.c
@@ -63,6 +63,9 @@ static VALUE doc_initialize(VALUE cls, VALUE _filename)
     const char*filename = StringValuePtr(_filename);
     doc->fontlist = gfxfontlist_create();
     doc->doc = pdfdriver->open(pdfdriver, filename);
+    if(!doc->doc) {
+       rb_raise(rb_eIOError, "couldn't open %s", filename);
+    }
     return cls;
 }