rewrite packet pad

lib/packet_pad_impl.cc

@@ -26,9 +26,11 @@ using namespace gr::foo;
 packet_pad_impl::packet_pad_impl(bool debug, unsigned int pad_front, unsigned int pad_tail) : block("packet_pad",
 			gr::io_signature::make(1, 1, sizeof(gr_complex)),
 			gr::io_signature::make(1, 1, sizeof(gr_complex))),
-			d_debug(debug), d_pad_front(pad_front),
-			d_pad_tail(pad_tail), d_front_left(0),
-			d_tail_left(0), d_frame_left(0), d_state(IDLE) {
+			d_debug(debug),
+			d_pad_front(pad_front),
+			d_pad_tail(pad_tail),
+			d_pad(0),
+			d_eob(false) {
 
 	set_relative_rate(1);
 	set_tag_propagation_policy(block::TPP_DONT);
@@ -62,146 +64,101 @@ packet_pad_impl::general_work (int noutput_items, gr_vector_int& ninput_items,
 		gr_vector_const_void_star& input_items,
 		gr_vector_void_star& output_items) {
 
-	int ninput = ninput_items[0];
-	int noutput = noutput_items;
-
 	// these 4 values are updated in each iteration
 	const gr_complex *in = (const gr_complex*)input_items[0];
 	gr_complex *out = (gr_complex*)output_items[0];
 
-	int written = 0;		// written symbols
-	int consumed = 0;		// read symbols
+	int ninput = ninput_items[0];
+	int noutput = noutput_items;
 
-	// tag handling
+	dout << "call: pad " << d_pad << "   ninput " << ninput << "  noutput " << noutput << std::endl;
+	// insert zeros
+	if(d_pad) {
+		int n = std::min(d_pad, noutput);
+		std::memset(out, 0, n * sizeof(gr_complex));
+		d_pad -= n;
+
+		dout << "padded zeros: " << n << std::endl;
+
+		// add end of burst tag
+		if(!d_pad && d_eob) {
+			d_eob = false;
+			add_eob(nitems_written(0) + n - 1);
+		}
+		return n;
+	}
+
+	// search for tags
 	const uint64_t nread = this->nitems_read(0);
 	std::vector<gr::tag_t> tags;
+	get_tags_in_range(tags, 0, nread, nread + ninput);
+	std::sort(tags.begin(), tags.end(), tag_t::offset_compare);
 
-	dout << "PACKET PAD: input size: " << ninput_items[0] << "   output size: "
-	     << noutput_items << std::endl;
+	uint64_t n = std::min(ninput, noutput);
 
-	while(written < noutput) {
+	if(tags.size()) {
+		tag_t t = tags[0];
 
-		dout << "PACKET PAD: iteration - consumed: " << consumed <<
-				"   written: " << written << std::endl;
+		dout << "found tag: " << pmt::symbol_to_string(t.key) << std::endl;
 
-		switch(d_state) {
+		uint64_t read = nitems_read(0);
+		if(t.offset != read) {
+			dout << "tag does not start at current offset" << std::endl;
+			n = std::min(n, t.offset - read);
 
-		case IDLE:
+		} else {
+			if(pmt::equal(t.key, pmt::mp("tx_sob"))) {
+				dout << "tx_sob tag" << std::endl;
+				add_sob(nitems_written(0));
+				d_pad = d_pad_front;
+				remove_item_tag(0, t);
+				return 0;
 
-			//assert(consumed < ninput);
-			if(consumed >= ninput) {
-				goto out;
+
+			} else if(pmt::equal(t.key, pmt::mp("tx_eob"))) {
+				dout << "tx_eob tag" << std::endl;
+				d_pad = d_pad_tail;
+				d_eob = true;
+				if(n) {
+
+					if(!d_pad) {
+						add_eob(nitems_written(0));
+						d_eob = false;
+					}
+					memcpy(out, in, sizeof(gr_complex));
+					consume(0, 1);
+					return 1;
+				}
+				return 0;
+
+			} else {
+				dout << "unknown tag" << std::endl;
+				if(tags.size() > 1) {
+					n = std::min(n, tags[1].offset - read);
+				}
 			}
-
-			get_tags_in_range(tags, 0, nread + consumed,
-					nread + (consumed + 1) - 1,
-					pmt::string_to_symbol("ofdm_start"));
-
-			assert(tags.size() == 1);
-
-			d_front_left = d_pad_front;
-			d_frame_left = pmt::to_uint64(tags[0].value);
-			d_tail_left = d_pad_tail;
-
-			add_sob(this->nitems_written(0) + written);
-			d_state = FRONT;
-
-			dout << "PACKET PAD: new frame - length: " << d_frame_left << std::endl;
-
-			break;
-
-		case FRONT:
-
-			if(!((ninput >= d_frame_left) || (ninput == 102))) {
-				goto out;
-			}
-
-			if(!d_front_left) {
-				d_state = FRAME;
-				break;
-			}
-
-			dout << "PACKET PAD: pad front" << std::endl;
-
-			memset(out, 0, sizeof(gr_complex));
-
-			d_front_left--;
-			out++;
-			written++;
-
-			break;
-
-		case FRAME:
-
-			//assert((consumed + 1) <= ninput_items[0]);
-			if(consumed >= ninput) {
-				goto out;
-			}
-
-			dout << "PACKET PAD: copy frame" << std::endl;
-
-			memcpy(out, in, sizeof(gr_complex));
-
-			d_frame_left--;
-			consumed++;
-			written++;
-			in++;
-			out++;
-
-			if(!d_frame_left) {
-				d_state = TAIL;
-				break;
-			}
-
-			break;
-
-		case TAIL:
-
-			if(!d_tail_left) {
-				d_state = IDLE;
-				add_eob(this->nitems_written(0) + written - 1);
-				goto out;
-			}
-
-			dout << "PACKET PAD: pad tail" << std::endl;
-
-			memset(out, 0, sizeof(gr_complex));
-
-			d_tail_left--;
-			written++;
-			out ++;
-
-			break;
-
-		default:
-			assert(false);
-			break;
 		}
 	}
 
-out:
+	dout << "copying : " << n << std::endl;
 
-	dout << "PACKET PAD: consumed: " << consumed << "   produced: " << written << std::endl;
-	consume(0, consumed);
-	return written;
+	std::memcpy(out, in, n * sizeof(gr_complex));
+	consume(0, n);
+	return n;
 }
 
 void
 packet_pad_impl::forecast (int noutput_items, gr_vector_int &ninput_items_required)
 {
 
-	if(d_frame_left) {
-		ninput_items_required[0] = noutput_items;
-
-	} else if(d_state == TAIL) {
+	if(d_pad) {
 		ninput_items_required[0] = 0;
 	} else {
-		ninput_items_required[0] = 80;
+		ninput_items_required[0] = noutput_items;
 	}
 
-	dout << "PAD forecast noutput_items: " << noutput_items << "  required: " << ninput_items_required[0] << std::endl;
-	dout << "PAD state " << d_state << std::endl;
-	dout << "d_frame_left " << d_frame_left << std::endl;
+	// dout << "PAD forecast noutput_items: " << noutput_items << "  required: " << ninput_items_required[0] << std::endl;
+	// dout << "d_pad " << d_pad << std::endl;
 }
 
 packet_pad::sptr

lib/packet_pad_impl.h

@@ -35,12 +35,8 @@ namespace foo {
 			int d_pad_front;
 			int d_pad_tail;
 
-			int d_front_left;
-			int d_tail_left;
-			int d_frame_left;
-
-			enum {IDLE, FRONT, FRAME, TAIL} d_state;
-
+			int d_pad;
+			bool d_eob;
 
 		public:
 			packet_pad_impl(bool debug, unsigned int pad_front,