1 files changed, 95 insertions, 0 deletions
diff --git a/grc/core/epy_block_io.py b/grc/core/epy_block_io.py
new file mode 100644
index 0000000000..e089908a01
--- /dev/null
+++ b/grc/core/epy_block_io.py
@@ -0,0 +1,95 @@
+
+import inspect
+import collections
+
+from gnuradio import gr
+import pmt
+
+
+TYPE_MAP = {
+    'complex64': 'complex', 'complex': 'complex',
+    'float32': 'float', 'float': 'float',
+    'int32': 'int', 'uint32': 'int',
+    'int16': 'short', 'uint16': 'short',
+    'int8': 'byte', 'uint8': 'byte',
+}
+
+BlockIO = collections.namedtuple('BlockIO', 'name cls params sinks sources doc')
+
+
+def _ports(sigs, msgs):
+    ports = list()
+    for i, dtype in enumerate(sigs):
+        port_type = TYPE_MAP.get(dtype.name, None)
+        if not port_type:
+            raise ValueError("Can't map {0:!r} to GRC port type".format(dtype))
+        ports.append((str(i), port_type))
+    for msg_key in msgs:
+        if msg_key == 'system':
+            continue
+        ports.append((msg_key, 'message'))
+    return ports
+
+
+def _blk_class(source_code):
+    ns = {}
+    try:
+        exec source_code in ns
+    except Exception as e:
+        raise ValueError("Can't interpret source code: " + str(e))
+    for var in ns.itervalues():
+        if inspect.isclass(var)and issubclass(var, gr.gateway.gateway_block):
+            return var
+    raise ValueError('No python block class found in code')
+
+
+def extract(cls):
+    if not inspect.isclass(cls):
+        cls = _blk_class(cls)
+
+    spec = inspect.getargspec(cls.__init__)
+    defaults = map(repr, spec.defaults or ())
+    doc = cls.__doc__ or cls.__init__.__doc__ or ''
+    cls_name = cls.__name__
+
+    if len(defaults) + 1 != len(spec.args):
+        raise ValueError("Need all __init__ arguments to have default values")
+
+    try:
+        instance = cls()
+    except Exception as e:
+        raise RuntimeError("Can't create an instance of your block: " + str(e))
+
+    name = instance.name()
+    params = list(zip(spec.args[1:], defaults))
+
+    sinks = _ports(instance.in_sig(),
+                   pmt.to_python(instance.message_ports_in()))
+    sources = _ports(instance.out_sig(),
+                     pmt.to_python(instance.message_ports_out()))
+
+    return BlockIO(name, cls_name, params, sinks, sources, doc)
+
+
+if __name__ == '__main__':
+    blk_code = """
+import numpy as np
+from gnuradio import gr
+import pmt
+
+class blk(gr.sync_block):
+    def __init__(self, param1=None, param2=None):
+        "Test Docu"
+        gr.sync_block.__init__(
+            self,
+            name='Embedded Python Block',
+            in_sig = (np.float32,),
+            out_sig = (np.float32,np.complex64,),
+        )
+        self.message_port_register_in(pmt.intern('msg_in'))
+        self.message_port_register_out(pmt.intern('msg_out'))
+
+    def work(self, inputs_items, output_items):
+        return 10
+    """
+    print extract(blk_code)