trace: add DTrace reserved words for .d files

DTrace on Mac OS X fails due to trace events using 'self' as an argument
name:

  GEN   trace/generated-tracers-dtrace.h
dtrace: failed to compile script trace/generated-tracers-dtrace.dtrace: line 1330: syntax error, unexpected DT_KEY_SELF, expecting ) near "self"
make: *** [trace/generated-tracers-dtrace.h] Error 1

Filter argument names according to the list of DTrace .d file reserved
keywords.

Note that DTrace on Mac and Linux still do not work after this patch.
There are additional build issues remaining.

Reported-by: Henk Poley <[email protected]>
Tested-by: Henk Poley <[email protected]>
Cc: Lluís Vilanova <[email protected]>
Signed-off-by: Stefan Hajnoczi <[email protected]>

scripts/tracetool/format/d.py

@@ -16,6 +16,19 @@
 from tracetool import out
 
 
+# Reserved keywords from
+# https://wikis.oracle.com/display/DTrace/Types,+Operators+and+Expressions
+RESERVED_WORDS = (
+    'auto', 'goto', 'sizeof', 'break', 'if', 'static', 'case', 'import',
+    'string', 'char', 'inline', 'stringof', 'const', 'int', 'struct',
+    'continue', 'long', 'switch', 'counter', 'offsetof', 'this',
+    'default', 'probe', 'translator', 'do', 'provider', 'typedef',
+    'double', 'register', 'union', 'else', 'restrict', 'unsigned',
+    'enum', 'return', 'void', 'extern', 'self', 'volatile', 'float',
+    'short', 'while', 'for', 'signed', 'xlate',
+)
+
+
 def generate(events, backend):
     events = [e for e in events
               if "disable" not in e.properties]
@@ -25,18 +38,17 @@ def generate(events, backend):
         'provider qemu {')
 
     for e in events:
-        args = str(e.args)
-
-        # DTrace provider syntax expects foo() for empty
-        # params, not foo(void)
-        if args == 'void':
-            args = ''
+        args = []
+        for type_, name in e.args:
+            if name in RESERVED_WORDS:
+                name += '_'
+            args.append(type_ + ' ' + name)
 
         # Define prototype for probe arguments
         out('',
             'probe %(name)s(%(args)s);',
             name=e.name,
-            args=args)
+            args=','.join(args))
 
     out('',
         '};')