diff options
Diffstat (limited to 'gr-blocks/lib')
| -rw-r--r-- | gr-blocks/lib/head_impl.cc | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/gr-blocks/lib/head_impl.cc b/gr-blocks/lib/head_impl.cc index 0ee22682d0..567a12d1df 100644 --- a/gr-blocks/lib/head_impl.cc +++ b/gr-blocks/lib/head_impl.cc @@ -1,6 +1,7 @@ /* -*- c++ -*- */ /* * Copyright 2004,2009,2013 Free Software Foundation, Inc. + * Copyright 2021 Marcus Müller * * This file is part of GNU Radio * @@ -27,7 +28,7 @@ head::sptr head::make(size_t sizeof_stream_item, uint64_t nitems) head_impl::head_impl(size_t sizeof_stream_item, uint64_t nitems) : sync_block("head", io_signature::make(1, 1, sizeof_stream_item), - io_signature::make(1, 1, sizeof_stream_item)), + io_signature::make(0, 1, sizeof_stream_item)), d_nitems(nitems), d_ncopied_items(0) { @@ -47,7 +48,12 @@ int head_impl::work(int noutput_items, if (n == 0) return 0; - memcpy(output_items[0], input_items[0], n * input_signature()->sizeof_stream_item(0)); + // can have zero or one output port, if zero, don't copy + if (!output_items.empty()) { + memcpy(output_items[0], + input_items[0], + n * input_signature()->sizeof_stream_item(0)); + } d_ncopied_items += n; return n; |