Rework codec

docs/data_types/codec.rst

@@ -0,0 +1,12 @@
+.. _codec_pkg:
+
+*codec* package
+---------------
+
+.. literalinclude:: ../../vunit/vhdl/data_types/src/codec.vhd
+   :language: vhdl
+   :lines: 22-229
+
+.. literalinclude:: ../../vunit/vhdl/data_types/src/codec-2008p.vhd
+   :language: vhdl
+   :lines: 24-71

docs/data_types/user_guide.rst

@@ -16,6 +16,11 @@ VUnit comes with a number of convenient data types included:
     append and reshape operations, and reading/writing data to/from
     *.csv* or *.raw* byte files.
 
+VUnit **queue_t** (:ref:`Queue API <queue_pkg>`) functionality is built
+on top of the **codec** (:ref:`Codec API <codec_pkg>`) package. The
+codec (:ref:`Codec API <codec_pkg>`) package enable to encode any
+predefined type into a unique type (each type is encoded into a string).
+
 .. toctree::
    :hidden:
 

vunit/com/codec_datatype_template.py

@@ -16,28 +16,40 @@ class DatatypeCodecTemplate(object):
 
     to_string_declarations = Template(
         """\
-  function to_string (
-    constant data : $type)
-    return string;
+  -- Printing function for the type $type
+  function to_string(data : $type) return string;
 
 """
     )
 
     codec_declarations = Template(
         """\
-  function encode (
-    constant data : $type)
-    return string;
-  alias encode_$type is encode[$type return string];
-  function decode (
-    constant code : string)
-    return $type;
-  alias decode_$type is decode[string return $type];
-  procedure decode (
-    constant code   : string;
-    variable index : inout positive;
-    variable result : out $type);
-  alias decode_$type is decode[string, positive, $type];
+  -----------------------------------------------------------------------------
+  -- Codec package extension for the type $type
+  -----------------------------------------------------------------------------
+
+  function encode_$type(data : $type) return code_t;
+  function decode_$type(code : code_t) return $type;
+  alias encode is encode_$type[$type return code_t];
+  alias decode is decode_$type[code_t return $type];
+  procedure encode_$type(
+    constant data  : in    $type;
+    variable index : inout code_index_t;
+    variable code  : inout code_t
+  );
+  procedure decode_$type(
+    constant code   : in    code_t;
+    variable index  : inout code_index_t;
+    variable result : out   $type
+  );
+  alias encode is encode_$type[$type, code_index_t, code_t];
+  alias decode is decode_$type[code_t, code_index_t, $type];
+
+
+  -----------------------------------------------------------------------------
+  -- Queue package extension for the type $type
+  -----------------------------------------------------------------------------
+
   procedure push(queue : queue_t; value : $type);
   impure function pop(queue : queue_t) return $type;
   alias push_$type is push[queue_t, $type];

vunit/com/codec_generator.py

@@ -54,6 +54,7 @@ def generate_codecs(
 library vunit_lib;
 use vunit_lib.string_ops.all;
 context vunit_lib.com_context;
+use vunit_lib.common_pkg.all;
 use vunit_lib.queue_pkg.all;
 use vunit_lib.queue_2008p_pkg.all;