elog-gen.py : implement error inheritance

If an error inherits another error (via the error YAML interface), have
the child error inherit parent's metadata. Only single inheritance is
supported as of now.

Change-Id: I9ff295f4db04a9c5389f66e04f5d28287f9628a9
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>

2 files changed, 12 insertions, 2 deletions

diff --git a/tools/elog-gen.py b/tools/elog-gen.py
index a6fdb1f..e9f4fc0 100755
--- a/tools/elog-gen.py
+++ b/tools/elog-gen.py
@@ -151,7 +151,8 @@ def gen_elog_hpp(i_yaml_dir, i_output_hpp,
     f.write(template.render(
             errors=errors, error_msg=error_msg,
             error_lvl=error_lvl, meta=meta,
-            meta_data=meta_data, error_namespace=i_error_namespace))
+            meta_data=meta_data, error_namespace=i_error_namespace,
+            parents=parents))
     f.close()
 
 
diff --git a/tools/phosphor-logging/templates/elog-gen-template.mako.hpp b/tools/phosphor-logging/templates/elog-gen-template.mako.hpp
index 4222f08..e39deea 100644
--- a/tools/phosphor-logging/templates/elog-gen-template.mako.hpp
+++ b/tools/phosphor-logging/templates/elog-gen-template.mako.hpp
@@ -42,7 +42,16 @@ struct ${b}
     % endfor
 
 }  // namespace _${classname}
-<% meta_string = ', '.join(meta[name]) %>
+<%
+    meta_string = ', '.join(meta[name])
+
+    parent = parents[name]
+    while parent:
+        parent_meta = [parent + "::" + p for p in meta[parent]]
+        parent_meta = ', '.join(parent_meta)
+        meta_string = meta_string + ", " + parent_meta
+        parent = parents[parent]
+%>
 struct ${classname}
 {
     static constexpr auto err_code = "${name}";