[lnst: 2/10] Add NetEm XML recipe parsing support

[jtluka]

commit 8e5294cd0842da4aef1e41db12ff1dc1b0c105d2
Author: Jiri Prochazka 
Date:   Thu May 21 14:24:17 2015 +0200

Add NetEm XML recipe parsing support

This patch adds parsing of XML elements identifying NetEm parameters.
    Along with parsing, basic syntax check is executed, checking if
    mandatory attributes are correctly entered.

Signed-off-by: Jiri Prochazka 
    Signed-off-by: Jan Tluka 
    Acked-by: Jiri Pirko

lnst/Controller/RecipeParser.py |   63 +++++++++++++++++++++++++++++++++++++++
 1 files changed, 63 insertions(+), 0 deletions(-)
---
diff --git a/lnst/Controller/RecipeParser.py b/lnst/Controller/RecipeParser.py
index 7269820..73422f1 100644
--- a/lnst/Controller/RecipeParser.py
+++ b/lnst/Controller/RecipeParser.py
@@ -111,6 +111,11 @@ class RecipeParser(XmlParser):
         if self._has_attribute(iface_tag, "netns"):
             iface["netns"] = self._get_attribute(iface_tag, "netns")

+        # netem
+        netem_tag = iface_tag.find("netem")
+        if netem_tag is not None:
+            iface["netem"] = self._process_netem(netem_tag)
+
         # params
         params_tag = iface_tag.find("params")
         params = self._process_params(params_tag)
@@ -269,6 +274,64 @@ class RecipeParser(XmlParser):

return options

+    def _validate_netem(self, options, netem_op, netem_tag):
+        if netem_op == "delay":
+            valid = False
+            jitter = False
+            correlation = False
+            distribution = False
+            valid_distributions = ["normal", "uniform", "pareto", "paretonormal"]
+            for opt in options:
+                if "time" in opt.values():
+                    valid = True
+                elif "distribution" in opt.values():
+                    if opt["value"] not in valid_distributions:
+                        raise RecipeError("netem: invalid distribution type", netem_tag)
+                    else:
+                        distribution = True
+                elif "jitter" in opt.values():
+                    jitter =  True
+                elif "correlation" in opt.values():
+                    correlation = True
+            if not jitter:
+                if correlation or distribution:
+                    raise RecipeError("netem: jitter option is mandatory when using <correlation> or <distribution>", netem_tag)
+            if not valid:
+                raise RecipeError("netem: time option is mandatory for <delay>", netem_tag)
+        elif netem_op == "loss":
+            for opt in options:
+                if "percent" in opt.values():
+                    return
+            raise RecipeError("netem: percent option is mandatory for <loss>", netem_tag)
+        elif netem_op == "duplication":
+            for opt in options:
+                if "percent" in opt.values():
+                    return
+            raise RecipeError("netem: percent option is mandatory for <duplication>", netem_tag)
+        elif netem_op == "corrupt":
+            for opt in options:
+                if "percent" in opt.values():
+                    return
+            raise RecipeError("netem: percent option is mandatory for <corrupt>", netem_tag)
+        elif netem_op == "reordering":
+            for opt in options:
+                if "percent" in opt.values():
+                    return
+            raise RecipeError("netem: percent option is mandatory for <reordering>", netem_tag)
+
+    def _process_netem(self, netem_tag):
+        interface = XmlData(netem_tag)
+        # params
+        for netem_op in ["delay", "loss", "duplication", "corrupt", "reordering"]:
+            netem_op_tag = netem_tag.find(netem_op)
+            if netem_op_tag is not None:
+                options_tag = netem_op_tag.find("options")
+                options = self._process_options(options_tag)
+                if len(options) > 0:
+                    self._validate_netem(options, netem_op, netem_tag)
+                    interface[netem_op] = options
+        return interface
+
     def _process_task(self, task_tag):
         task = XmlData(task_tag)