13 files changed, 849 insertions, 0 deletions
diff --git a/gr-blocks/CMakeLists.txt b/gr-blocks/CMakeLists.txt
index 13b41a2e3c..685f5736fb 100644
--- a/gr-blocks/CMakeLists.txt
+++ b/gr-blocks/CMakeLists.txt
@@ -87,6 +87,7 @@ add_subdirectory(lib)
 #endif(ENABLE_TESTING)
 if(ENABLE_PYTHON)
      add_subdirectory(python/blocks)
+     add_subdirectory(python/grc_gnuradio)
      add_subdirectory(swig)
      add_subdirectory(grc)
      add_subdirectory(doc)
diff --git a/gr-blocks/grc/blks2_error_rate.xml b/gr-blocks/grc/blks2_error_rate.xml
new file mode 100644
index 0000000000..91a303206d
--- /dev/null
+++ b/gr-blocks/grc/blks2_error_rate.xml
@@ -0,0 +1,69 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Error Rate:
+##	Custom blks2 block
+###################################################
+ -->
+<block>
+	<name>Error Rate</name>
+	<key>blks2_error_rate</key>
+	<import>from grc_gnuradio import blks2 as grc_blks2</import>
+	<make>grc_blks2.error_rate(
+	type=$type,
+	win_size=$win_size,
+	bits_per_symbol=$bits_per_symbol,
+)</make>
+	<param>
+		<name>Type</name>
+		<key>type</key>
+		<type>enum</type>
+		<option>
+			<name>Bit Error Rate</name>
+			<key>'BER'</key>
+			<opt>hide_bps:</opt>
+		</option>
+		<option>
+			<name>Symbol Error Rate</name>
+			<key>'SER'</key>
+			<opt>hide_bps:all</opt>
+		</option>
+	</param>
+	<param>
+		<name>Window Size</name>
+		<key>win_size</key>
+		<value>1000</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Bits per Symbol</name>
+		<key>bits_per_symbol</key>
+		<value>2</value>
+		<type>int</type>
+		<hide>$type.hide_bps</hide>
+	</param>
+	<sink>
+		<name>ref</name>
+		<type>byte</type>
+	</sink>
+	<sink>
+		<name>in</name>
+		<type>byte</type>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>float</type>
+	</source>
+	<doc>
+Calculate the bit error rate (BER) or the symbol error rate (SER) over a number of samples given by the window size. \
+The actual window size will start at size one and grow to the full window size as new samples arrive. \
+Once the window has reached full size, old samples are shifted out of the window and new samples shfited in.
+
+The error block compares the input byte stream to the reference byte stream. \
+For example, the reference byte stream could be the input to a modulator, \
+and the input byte stream could be the output of a modulator.
+
+Each byte in the incoming stream represents one symbol. \
+The bits per symbol parameter is only useful for calculating the BER.
+	</doc>
+</block>
diff --git a/gr-blocks/grc/blks2_selector.xml b/gr-blocks/grc/blks2_selector.xml
new file mode 100644
index 0000000000..2d89df1860
--- /dev/null
+++ b/gr-blocks/grc/blks2_selector.xml
@@ -0,0 +1,97 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Selector:
+##	Custom blks2 block
+###################################################
+ -->
+<block>
+	<name>Selector</name>
+	<key>blks2_selector</key>
+	<import>from grc_gnuradio import blks2 as grc_blks2</import>
+	<make>grc_blks2.selector(
+	item_size=$type.size*$vlen,
+	num_inputs=$num_inputs,
+	num_outputs=$num_outputs,
+	input_index=$input_index,
+	output_index=$output_index,
+)</make>
+	<callback>set_input_index(int($input_index))</callback>
+	<callback>set_output_index(int($output_index))</callback>
+	<param>
+		<name>Type</name>
+		<key>type</key>
+		<type>enum</type>
+		<option>
+			<name>Complex</name>
+			<key>complex</key>
+			<opt>size:gr.sizeof_gr_complex</opt>
+		</option>
+		<option>
+			<name>Float</name>
+			<key>float</key>
+			<opt>size:gr.sizeof_float</opt>
+		</option>
+		<option>
+			<name>Int</name>
+			<key>int</key>
+			<opt>size:gr.sizeof_int</opt>
+		</option>
+		<option>
+			<name>Short</name>
+			<key>short</key>
+			<opt>size:gr.sizeof_short</opt>
+		</option>
+		<option>
+			<name>Byte</name>
+			<key>byte</key>
+			<opt>size:gr.sizeof_char</opt>
+		</option>
+	</param>
+	<param>
+		<name>Num Inputs</name>
+		<key>num_inputs</key>
+		<value>2</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Num Outputs</name>
+		<key>num_outputs</key>
+		<value>2</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Input Index</name>
+		<key>input_index</key>
+		<value>0</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Output Index</name>
+		<key>output_index</key>
+		<value>0</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Vec Length</name>
+		<key>vlen</key>
+		<value>1</value>
+		<type>int</type>
+	</param>
+	<check>$vlen &gt; 0</check>
+	<sink>
+		<name>in</name>
+		<type>$type</type>
+		<vlen>$vlen</vlen>
+		<nports>$num_inputs</nports>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>$type</type>
+		<vlen>$vlen</vlen>
+		<nports>$num_outputs</nports>
+	</source>
+	<doc>
+Connect the sink at input index to the source at output index. Leave all other ports disconnected.
+	</doc>
+</block>
diff --git a/gr-blocks/grc/blks2_tcp_sink.xml b/gr-blocks/grc/blks2_tcp_sink.xml
new file mode 100644
index 0000000000..46b10a7790
--- /dev/null
+++ b/gr-blocks/grc/blks2_tcp_sink.xml
@@ -0,0 +1,90 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##TCP Sink: Custom blks2 block
+###################################################
+ -->
+<block>
+	<name>TCP Sink</name>
+	<key>blks2_tcp_sink</key>
+	<category>Deprecated</category>
+	<import>from grc_gnuradio import blks2 as grc_blks2</import>
+	<make>grc_blks2.tcp_sink(
+	itemsize=$type.size*$vlen,
+	addr=$addr,
+	port=$port,
+	server=$server,
+)</make>
+	<param>
+		<name>Input Type</name>
+		<key>type</key>
+		<type>enum</type>
+		<option>
+			<name>Complex</name>
+			<key>complex</key>
+			<opt>size:gr.sizeof_gr_complex</opt>
+		</option>
+		<option>
+			<name>Float</name>
+			<key>float</key>
+			<opt>size:gr.sizeof_float</opt>
+		</option>
+		<option>
+			<name>Int</name>
+			<key>int</key>
+			<opt>size:gr.sizeof_int</opt>
+		</option>
+		<option>
+			<name>Short</name>
+			<key>short</key>
+			<opt>size:gr.sizeof_short</opt>
+		</option>
+		<option>
+			<name>Byte</name>
+			<key>byte</key>
+			<opt>size:gr.sizeof_char</opt>
+		</option>
+	</param>
+	<param>
+		<name>Address</name>
+		<key>addr</key>
+		<value>127.0.0.1</value>
+		<type>string</type>
+	</param>
+	<param>
+		<name>Port</name>
+		<key>port</key>
+		<value>0</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Mode</name>
+		<key>server</key>
+		<value>False</value>
+		<type>enum</type>
+		<option>
+			<name>Server</name>
+			<key>True</key>
+		</option>
+		<option>
+			<name>Client</name>
+			<key>False</key>
+		</option>
+	</param>
+	<param>
+		<name>Vec Length</name>
+		<key>vlen</key>
+		<value>1</value>
+		<type>int</type>
+	</param>
+	<check>$vlen &gt; 0</check>
+	<sink>
+		<name>in</name>
+		<type>$type</type>
+		<vlen>$vlen</vlen>
+	</sink>
+		<doc>
+In client mode, we attempt to connect to a server at the given address and port. \
+In server mode, we bind a socket to the given address and port and accept the first client.
+	</doc>
+</block>
diff --git a/gr-blocks/grc/blks2_tcp_source.xml b/gr-blocks/grc/blks2_tcp_source.xml
new file mode 100644
index 0000000000..6bf742aa00
--- /dev/null
+++ b/gr-blocks/grc/blks2_tcp_source.xml
@@ -0,0 +1,89 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##TCP Source: Custom blks2 block
+###################################################
+ -->
+<block>
+	<name>TCP Source</name>
+	<key>blks2_tcp_source</key>
+	<import>from grc_gnuradio import blks2 as grc_blks2</import>
+	<make>grc_blks2.tcp_source(
+	itemsize=$type.size*$vlen,
+	addr=$addr,
+	port=$port,
+	server=$server,
+)</make>
+	<param>
+		<name>Output Type</name>
+		<key>type</key>
+		<type>enum</type>
+		<option>
+			<name>Complex</name>
+			<key>complex</key>
+			<opt>size:gr.sizeof_gr_complex</opt>
+		</option>
+		<option>
+			<name>Float</name>
+			<key>float</key>
+			<opt>size:gr.sizeof_float</opt>
+		</option>
+		<option>
+			<name>Int</name>
+			<key>int</key>
+			<opt>size:gr.sizeof_int</opt>
+		</option>
+		<option>
+			<name>Short</name>
+			<key>short</key>
+			<opt>size:gr.sizeof_short</opt>
+		</option>
+		<option>
+			<name>Byte</name>
+			<key>byte</key>
+			<opt>size:gr.sizeof_char</opt>
+		</option>
+	</param>
+	<param>
+		<name>Address</name>
+		<key>addr</key>
+		<value>127.0.0.1</value>
+		<type>string</type>
+	</param>
+	<param>
+		<name>Port</name>
+		<key>port</key>
+		<value>0</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Mode</name>
+		<key>server</key>
+		<value>True</value>
+		<type>enum</type>
+		<option>
+			<name>Server</name>
+			<key>True</key>
+		</option>
+		<option>
+			<name>Client</name>
+			<key>False</key>
+		</option>
+	</param>
+	<param>
+		<name>Vec Length</name>
+		<key>vlen</key>
+		<value>1</value>
+		<type>int</type>
+	</param>
+	<check>$vlen &gt; 0</check>
+	<source>
+		<name>out</name>
+		<type>$type</type>
+		<vlen>$vlen</vlen>
+	</source>
+	<doc>
+In client mode, we attempt to connect to a server at the given address and port. \
+In server mode, we bind a socket to the given address and port and accept the first client.
+	</doc>
+</block>
diff --git a/gr-blocks/grc/blks2_valve.xml b/gr-blocks/grc/blks2_valve.xml
new file mode 100644
index 0000000000..47c553523f
--- /dev/null
+++ b/gr-blocks/grc/blks2_valve.xml
@@ -0,0 +1,72 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Valve:
+##	Custom blks2 block
+###################################################
+ -->
+<block>
+	<name>Valve</name>
+	<key>blks2_valve</key>
+	<import>from grc_gnuradio import blks2 as grc_blks2</import>
+	<make>grc_blks2.valve(item_size=$type.size*$vlen, open=bool($open))</make>
+	<callback>set_open(bool($open))</callback>
+	<param>
+		<name>Type</name>
+		<key>type</key>
+		<type>enum</type>
+		<option>
+			<name>Complex</name>
+			<key>complex</key>
+			<opt>size:gr.sizeof_gr_complex</opt>
+		</option>
+		<option>
+			<name>Float</name>
+			<key>float</key>
+			<opt>size:gr.sizeof_float</opt>
+		</option>
+		<option>
+			<name>Int</name>
+			<key>int</key>
+			<opt>size:gr.sizeof_int</opt>
+		</option>
+		<option>
+			<name>Short</name>
+			<key>short</key>
+			<opt>size:gr.sizeof_short</opt>
+		</option>
+		<option>
+			<name>Byte</name>
+			<key>byte</key>
+			<opt>size:gr.sizeof_char</opt>
+		</option>
+	</param>
+	<param>
+		<name>Open</name>
+		<key>open</key>
+		<value>0</value>
+		<type>raw</type>
+	</param>
+	<param>
+		<name>Vec Length</name>
+		<key>vlen</key>
+		<value>1</value>
+		<type>int</type>
+	</param>
+	<check>$vlen &gt; 0</check>
+	<sink>
+		<name>in</name>
+		<type>$type</type>
+		<vlen>$vlen</vlen>
+		<nports>$num_inputs</nports>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>$type</type>
+		<vlen>$vlen</vlen>
+		<nports>$num_outputs</nports>
+	</source>
+	<doc>
+Connect output to input when valve is closed (not open).
+	</doc>
+</block>
diff --git a/gr-blocks/python/grc_gnuradio/CMakeLists.txt b/gr-blocks/python/grc_gnuradio/CMakeLists.txt
new file mode 100644
index 0000000000..9ff1240997
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/CMakeLists.txt
@@ -0,0 +1,37 @@
+# Copyright 2011 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+
+########################################################################
+
+include(GrPython)
+
+GR_PYTHON_INSTALL(
+    FILES __init__.py
+    DESTINATION ${GR_PYTHON_DIR}/grc_gnuradio
+    COMPONENT "blocks_python"
+)
+
+GR_PYTHON_INSTALL(FILES
+    blks2/__init__.py
+    blks2/error_rate.py
+    blks2/selector.py
+    blks2/tcp.py
+    DESTINATION ${GR_PYTHON_DIR}/grc_gnuradio/blks2
+    COMPONENT "blocks_python"
+)
diff --git a/gr-blocks/python/grc_gnuradio/README b/gr-blocks/python/grc_gnuradio/README
new file mode 100644
index 0000000000..897eed65ca
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/README
@@ -0,0 +1,11 @@
+This is the grc_gnuradio module.
+It contains supplemental python modules that grc uses at runtime.
+The supplemental modules are meant to mimic modules in gnuradio.
+These will be phased-out as new functionaility is merged into gnuradio.
+
+The blk2s module wraps many blocks in blks2 and gives them streaming outputs.
+Will be phased-out by new message passing implementations.
+Other blks2 blocks will hopefully make their way into blks2impl.
+
+The wxgui module contains a top_block + wxgui frame.
+Will be phased-out by gui.py in wxgui and a new top block template.
diff --git a/gr-blocks/python/grc_gnuradio/__init__.py b/gr-blocks/python/grc_gnuradio/__init__.py
new file mode 100644
index 0000000000..8b13789179
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/__init__.py
@@ -0,0 +1 @@
+
diff --git a/gr-blocks/python/grc_gnuradio/blks2/__init__.py b/gr-blocks/python/grc_gnuradio/blks2/__init__.py
new file mode 100644
index 0000000000..d3c8210834
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/blks2/__init__.py
@@ -0,0 +1,30 @@
+# Copyright 2008-2011 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+from selector import selector, valve
+from error_rate import error_rate
+from tcp import tcp_source, tcp_sink
+
+try:
+    from packet import options, packet_encoder, packet_decoder, \
+        packet_mod_b, packet_mod_s, packet_mod_i, packet_mod_f, packet_mod_c, \
+        packet_demod_b, packet_demod_s, packet_demod_i, packet_demod_f, packet_demod_c
+except ImportError:
+    pass  # only available if gr-digital is install
diff --git a/gr-blocks/python/grc_gnuradio/blks2/error_rate.py b/gr-blocks/python/grc_gnuradio/blks2/error_rate.py
new file mode 100644
index 0000000000..9bf387030a
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/blks2/error_rate.py
@@ -0,0 +1,140 @@
+# Copyright 2008 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+default_win_size = 1000
+
+from gnuradio import gr
+from gnuradio import blocks
+import gnuradio.gr.gr_threading as _threading
+import numpy
+
+#generate 1s counts array
+_1s_counts = [sum([1&(i>>j) for j in range(8)]) for i in range(2**8)]
+
+class input_watcher(_threading.Thread):
+    """
+    Read samples from the message queue and hand them to the callback.
+    """
+
+    def __init__(self, msgq, callback):
+        self._msgq = msgq
+        self._callback = callback
+        _threading.Thread.__init__(self)
+        self.setDaemon(1)
+        self.keep_running = True
+        self.start()
+
+    def run(self):
+        r = ''
+        while True:
+            msg = self._msgq.delete_head()
+            itemsize = int(msg.arg1())
+            nitems = int(msg.arg2())
+            s = r + msg.to_string()
+            i = (nitems-nitems%2)*itemsize
+            r = s[i:]
+            s = s[:i]
+            samples = numpy.fromstring(s, numpy.int8)
+            self._callback(samples)
+
+class error_rate(gr.hier_block2):
+    """
+    Sample the incoming data streams (byte) and calculate the bit or symbol error rate.
+    Write the running rate to the output data stream (float).
+    """
+
+    def __init__(self, type='BER', win_size=default_win_size, bits_per_symbol=2):
+        """
+        Error rate constructor.
+
+        Args:
+            type: a string 'BER' or 'SER'
+            win_size: the number of samples to calculate over
+            bits_per_symbol: the number of information bits per symbol (BER only)
+        """
+        #init
+        gr.hier_block2.__init__(
+            self, 'error_rate',
+            gr.io_signature(2, 2, gr.sizeof_char),
+            gr.io_signature(1, 1, gr.sizeof_float),
+        )
+        assert type in ('BER', 'SER')
+        self._max_samples = win_size
+        self._bits_per_symbol = bits_per_symbol
+        #setup message queue
+        msg_source = blocks.message_source(gr.sizeof_float, 1)
+        self._msgq_source = msg_source.msgq()
+        msgq_sink = gr.msg_queue(2)
+        msg_sink = blocks.message_sink(gr.sizeof_char, msgq_sink, False) #False -> blocking
+        inter = blocks.interleave(gr.sizeof_char)
+        #start thread
+        self._num_errs = 0
+        self._err_index = 0
+        self._num_samps = 0
+        self._err_array = numpy.zeros(self._max_samples, numpy.int8)
+        if type == 'BER':
+            input_watcher(msgq_sink, self._handler_ber)
+        elif type == 'SER':
+            input_watcher(msgq_sink, self._handler_ser)
+        #connect
+        self.connect(msg_source, self)
+        self.connect((self, 0), (inter, 0))
+        self.connect((self, 1), (inter, 1))
+        self.connect(inter, msg_sink)
+
+    def _handler_ber(self, samples):
+        num = len(samples)/2
+        arr = numpy.zeros(num, numpy.float32)
+        for i in range(num):
+            old_err = self._err_array[self._err_index]
+            #record error
+            self._err_array[self._err_index] = _1s_counts[samples[i*2] ^ samples[i*2 + 1]]
+            self._num_errs = self._num_errs + self._err_array[self._err_index] - old_err
+            #increment index
+            self._err_index = (self._err_index + 1)%self._max_samples
+            self._num_samps = min(self._num_samps + 1, self._max_samples)
+            #write sample
+            arr[i] = float(self._num_errs)/float(self._num_samps*self._bits_per_symbol)
+        #write message
+        msg = gr.message_from_string(arr.tostring(), 0, gr.sizeof_float, num)
+        self._msgq_source.insert_tail(msg)
+
+    def _handler_ser(self, samples):
+        num = len(samples)/2
+        arr = numpy.zeros(num, numpy.float32)
+        for i in range(num):
+            old_err = self._err_array[self._err_index]
+            #record error
+            ref = samples[i*2]
+            res = samples[i*2 + 1]
+            if ref == res:
+                self._err_array[self._err_index] = 0
+            else:
+                self._err_array[self._err_index] = 1
+            #update number of errors
+            self._num_errs = self._num_errs + self._err_array[self._err_index] - old_err
+            #increment index
+            self._err_index = (self._err_index + 1)%self._max_samples
+            self._num_samps = min(self._num_samps + 1, self._max_samples)
+            #write sample
+            arr[i] = float(self._num_errs)/float(self._num_samps)
+        #write message
+        msg = gr.message_from_string(arr.tostring(), 0, gr.sizeof_float, num)
+        self._msgq_source.insert_tail(msg)
diff --git a/gr-blocks/python/grc_gnuradio/blks2/selector.py b/gr-blocks/python/grc_gnuradio/blks2/selector.py
new file mode 100644
index 0000000000..24e3844658
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/blks2/selector.py
@@ -0,0 +1,142 @@
+#
+# Copyright 2008,2013 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+from gnuradio import gr
+from gnuradio import blocks
+
+class selector(gr.hier_block2):
+    """A hier2 block with N inputs and M outputs, where data is only forwarded through input n to output m."""
+    def __init__(self, item_size, num_inputs, num_outputs, input_index, output_index):
+        """
+        Selector constructor.
+
+        Args:
+            item_size: the size of the gr data stream in bytes
+            num_inputs: the number of inputs (integer)
+            num_outputs: the number of outputs (integer)
+            input_index: the index for the source data
+            output_index: the index for the destination data
+        """
+        gr.hier_block2.__init__(
+            self, 'selector',
+            gr.io_signature(num_inputs, num_inputs, item_size),
+            gr.io_signature(num_outputs, num_outputs, item_size),
+        )
+        #terminator blocks for unused inputs and outputs
+        self.input_terminators = [blocks.null_sink(item_size) for i in range(num_inputs)]
+        self.output_terminators = [blocks.head(item_size, 0) for i in range(num_outputs)]
+        self.copy = blocks.copy(item_size)
+        #connections
+        for i in range(num_inputs): self.connect((self, i), self.input_terminators[i])
+        for i in range(num_outputs): self.connect(blocks.null_source(item_size),
+                                                          self.output_terminators[i], (self, i))
+        self.item_size = item_size
+        self.input_index = input_index
+        self.output_index = output_index
+        self.num_inputs = num_inputs
+        self.num_outputs = num_outputs
+        self._connect_current()
+
+    def _indexes_valid(self):
+        """
+        Are the input and output indexes within range of the number of inputs and outputs?
+
+        Returns:
+            true if input index and output index are in range
+        """
+        return self.input_index in range(self.num_inputs) and self.output_index in range(self.num_outputs)
+
+    def _connect_current(self):
+        """If the input and output indexes are valid:
+        disconnect the blocks at the input and output index from their terminators,
+        and connect them to one another. Then connect the terminators to one another."""
+        if self._indexes_valid():
+            self.disconnect((self, self.input_index), self.input_terminators[self.input_index])
+            self.disconnect(self.output_terminators[self.output_index], (self, self.output_index))
+            self.connect((self, self.input_index), self.copy)
+            self.connect(self.copy, (self, self.output_index))
+            self.connect(self.output_terminators[self.output_index], self.input_terminators[self.input_index])
+
+    def _disconnect_current(self):
+        """If the input and output indexes are valid:
+        disconnect the blocks at the input and output index from one another,
+        and the terminators at the input and output index from one another.
+        Reconnect the blocks to the terminators."""
+        if self._indexes_valid():
+            self.disconnect((self, self.input_index), self.copy)
+            self.disconnect(self.copy, (self, self.output_index))
+            self.disconnect(self.output_terminators[self.output_index], self.input_terminators[self.input_index])
+            self.connect((self, self.input_index), self.input_terminators[self.input_index])
+            self.connect(self.output_terminators[self.output_index], (self, self.output_index))
+
+    def set_input_index(self, input_index):
+        """
+        Change the block to the new input index if the index changed.
+
+        Args:
+            input_index: the new input index
+        """
+        if self.input_index != input_index:
+            self.lock()
+            self._disconnect_current()
+            self.input_index = input_index
+            self._connect_current()
+            self.unlock()
+
+    def set_output_index(self, output_index):
+        """
+        Change the block to the new output index if the index changed.
+
+        Args:
+            output_index: the new output index
+        """
+        if self.output_index != output_index:
+            self.lock()
+            self._disconnect_current()
+            self.output_index = output_index
+            self._connect_current()
+            self.unlock()
+
+class valve(selector):
+    """Wrapper for selector with 1 input and 1 output."""
+
+    def __init__(self, item_size, open):
+        """
+        Constructor for valve.
+
+        Args:
+            item_size: the size of the gr data stream in bytes
+            open: true if initial valve state is open
+        """
+        if open: output_index = -1
+        else: output_index = 0
+        selector.__init__(self, item_size, 1, 1, 0, output_index)
+
+    def set_open(self, open):
+        """
+        Callback to set open state.
+
+        Args:
+            open: true to set valve state to open
+        """
+        if open: output_index = -1
+        else: output_index = 0
+        self.set_output_index(output_index)
diff --git a/gr-blocks/python/grc_gnuradio/blks2/tcp.py b/gr-blocks/python/grc_gnuradio/blks2/tcp.py
new file mode 100644
index 0000000000..aee90fad2c
--- /dev/null
+++ b/gr-blocks/python/grc_gnuradio/blks2/tcp.py
@@ -0,0 +1,70 @@
+#
+# Copyright 2009 Free Software Foundation, Inc.
+#
+# This file is part of GNU Radio
+#
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+#
+
+from gnuradio import gr, blocks
+import socket
+import os
+
+def _get_sock_fd(addr, port, server):
+    """
+    Get the file descriptor for the socket.
+    As a client, block on connect, dup the socket descriptor.
+    As a server, block on accept, dup the client descriptor.
+
+    Args:
+        addr: the ip address string
+        port: the tcp port number
+        server: true for server mode, false for client mode
+
+    Returns:
+        the file descriptor number
+    """
+    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    if server:
+        sock.bind((addr, port))
+        sock.listen(1)
+        clientsock, address = sock.accept()
+        return os.dup(clientsock.fileno())
+    else:
+        sock.connect((addr, port))
+        return os.dup(sock.fileno())
+
+class tcp_source(gr.hier_block2):
+    def __init__(self, itemsize, addr, port, server=True):
+        #init hier block
+        gr.hier_block2.__init__(
+            self, 'tcp_source',
+            gr.io_signature(0, 0, 0),
+            gr.io_signature(1, 1, itemsize),
+        )
+        fd = _get_sock_fd(addr, port, server)
+        self.connect(blocks.file_descriptor_source(itemsize, fd), self)
+
+class tcp_sink(gr.hier_block2):
+    def __init__(self, itemsize, addr, port, server=False):
+        #init hier block
+        gr.hier_block2.__init__(
+            self, 'tcp_sink',
+            gr.io_signature(1, 1, itemsize),
+            gr.io_signature(0, 0, 0),
+        )
+        fd = _get_sock_fd(addr, port, server)
+        self.connect(self, blocks.file_descriptor_sink(itemsize, fd))