From bf232a6e6e73d156c9a46c26842480352c6794c0 Mon Sep 17 00:00:00 2001
From: Josh Blum <josh@joshknows.com>
Date: Thu, 20 Aug 2009 01:30:23 -0700
Subject: [PATCH] added continuation mode for pad source and sinks

---
 grc/base/Block.py          |  4 +++-
 grc/blocks/pad_sink.xml    | 21 ++++++++++++++++++---
 grc/blocks/pad_source.xml  | 31 +++++++++++++++++++++++++++----
 grc/python/flow_graph.tmpl | 17 +++++++++++++++++
 grc/todo.txt               |  2 ++
 5 files changed, 67 insertions(+), 8 deletions(-)

diff --git a/grc/base/Block.py b/grc/base/Block.py
index 82d27656..349e71f7 100644
--- a/grc/base/Block.py
+++ b/grc/base/Block.py
@@ -47,7 +47,9 @@ class TemplateArg(UserDict):
 		return self._param.get_evaluated()
 
 def _get_keys(lst): return [elem.get_key() for elem in lst]
-def _get_elem(lst, key): return lst[_get_keys(lst).index(key)]
+def _get_elem(lst, key):
+	try: return lst[_get_keys(lst).index(key)]
+	except ValueError: raise ValueError, 'Key "%s" not found in %s.'%(key, _get_keys(lst))
 
 class Block(Element):
 
diff --git a/grc/blocks/pad_sink.xml b/grc/blocks/pad_sink.xml
index 477f2ad1..999de315 100644
--- a/grc/blocks/pad_sink.xml
+++ b/grc/blocks/pad_sink.xml
@@ -8,6 +8,20 @@
 	<name>Pad Sink</name>
 	<key>pad_sink</key>
 	<make></make>
+	<param>
+		<name>Mode</name>
+		<key>mode</key>
+		<value>hb</value>
+		<type>enum</type>
+		<option>
+			<name>Hierarchical</name>
+			<key>hb</key>
+		</option>
+		<option>
+			<name>Continuation</name>
+			<key>cont</key>
+		</option>
+	</param>
 	<param>
 		<name>Num Inputs</name>
 		<key>nports</key>
@@ -59,10 +73,11 @@
 		<nports>$nports</nports>
 	</sink>
 	<doc>
-This is a sink pad block for creating hierarchical flow graphs. \
+Continuation Mode:
+The inputs of this block can be aliased by one or more pad source blocks.
+
+Hierarchical Mode:
 The inputs of this block will become the outputs to this flow graph when it is instantiated as a hierarchical block. \
 Limit one sink pad block per flow graph.
-
-Remember to set the generate options to hier block.
 	</doc>
 </block>
diff --git a/grc/blocks/pad_source.xml b/grc/blocks/pad_source.xml
index b6ef2c55..26491adb 100644
--- a/grc/blocks/pad_source.xml
+++ b/grc/blocks/pad_source.xml
@@ -8,6 +8,20 @@
 	<name>Pad Source</name>
 	<key>pad_source</key>
 	<make></make>
+	<param>
+		<name>Mode</name>
+		<key>mode</key>
+		<value>hb</value>
+		<type>enum</type>
+		<option>
+			<name>Hierarchical</name>
+			<key>hb</key>
+		</option>
+		<option>
+			<name>Continuation</name>
+			<key>cont</key>
+		</option>
+	</param>
 	<param>
 		<name>Num Outputs</name>
 		<key>nports</key>
@@ -50,6 +64,13 @@
 		<value>1</value>
 		<type>int</type>
 	</param>
+	<param>
+		<name>Pad Sink ID</name>
+		<key>pad_sink_id</key>
+		<value>pad_sink_0</value>
+		<type>string</type>
+		<hide>#if $mode() == 'cont' then 'none' else 'all'#</hide>
+	</param>
 	<check>$vlen &gt; 0</check>
 	<check>0 &lt; $nports</check>
 	<source>
@@ -59,10 +80,12 @@
 		<nports>$nports</nports>
 	</source>
 	<doc>
-This is a source pad block for creating hierarchical flow graphs. \
-The outputs of this block will become the inputs to this flow graph when it is instantiated as a hierarchical block. \
-Limit one source pad block per flow graph.
+Continuation Mode:
+The outputs of this block will alias the inputs of the pad sink specified by "pad sink id".
 
-Remember to set the generate options to hier block.
+Hierarchical Mode:
+The outputs of this block will become the inputs to this flow graph when it is instantiated as a hierarchical block. \
+Limit one source pad block per flow graph. \
+The "pad sink id" will be ignored in this mode.
 	</doc>
 </block>
diff --git a/grc/python/flow_graph.tmpl b/grc/python/flow_graph.tmpl
index df346dd1..32139636 100644
--- a/grc/python/flow_graph.tmpl
+++ b/grc/python/flow_graph.tmpl
@@ -161,8 +161,20 @@ class $(class_name)(gr.hier_block2):
 		$DIVIDER
 #end if
 #for $con in $connections
+	####################################################################
+	## Logic to extract source and sink
+	##   Special resolution logic for pad source in continuation mode
+	####################################################################
 	#set $source = $con.get_source()
 	#set $sink = $con.get_sink()
+	#if $source.get_parent().get_key() == 'pad_source' and $source.get_parent().get_param('mode').get_value() == 'cont'
+		#set $pad_sink_id = $source.get_parent().get_param('pad_sink_id').get_evaluated()
+		#set $pad_sink = filter(lambda b: b.get_id() == pad_sink_id, $blocks)[0]
+		#set $source = $pad_sink.get_sink($source.get_key()).get_connections()[0].get_source()
+	#end if
+	####################################################################
+	## Logic to extract source and sink names
+	####################################################################
 	#if $source.get_parent().get_key() == 'pad_source'
 		#set $source_name = 'self'
 	#else
@@ -173,7 +185,12 @@ class $(class_name)(gr.hier_block2):
 	#else
 		#set $sink_name = 'self.' + $sink.get_parent().get_id()
 	#end if
+	####################################################################
+	## Dont make a connection for continuation pad sinks!!!
+	####################################################################
+	#if not ($sink.get_parent().get_key() == 'pad_sink' and $sink.get_parent().get_param('mode').get_value() == 'cont')
 		self.connect(($source_name, $source.get_key()), ($sink_name, $sink.get_key()))
+	#end if
 #end for
 
 ########################################################
diff --git a/grc/todo.txt b/grc/todo.txt
index bb40e1f1..577e4c33 100644
--- a/grc/todo.txt
+++ b/grc/todo.txt
@@ -59,6 +59,8 @@
 ##################################################
 # Problems
 ##################################################
+* need a way to make an id param in the xml that will override the default
+  * ex: display pad sink id in continuation mode using hide tag for id param
 * hier block generation
   * auto generate hier library on changes
   * auto clean hier library when block removed
-- 
2.47.2