cooker: use BBHandler.inherit for INHERIT

Ideally we'd avoid direct BBHandler usage, but honestly, to say the whole
bb.parse abstraction is incredibly leaky is an understatement.  If we try to
make handle() not reparse classes, things get ugly fairly quickly, as
inherit() calls handle() itself after adding the class to the inherit cache.

This change fixes it so we no longer risk reparsing a class if:

- it's listed in INHERIT multiple times
- it's listed in INHERIT and is 'inherit'ed from a class in INHERIT

(Bitbake rev: 057c3cddeb72584c6c3908bd702288cece9b66ea)

Signed-off-by: Chris Larson <chris_larson@mentor.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/cooker.py

@@ -33,6 +33,7 @@ import sre_constants
 import threading
 from cStringIO import StringIO
 from contextlib import closing
+from functools import wraps
 import bb, bb.exceptions
 from bb import utils, data, parse, event, cache, providers, taskdata, command, runqueue
 
@@ -637,13 +638,6 @@ class BBCooker:
             path, _ = os.path.split(path)
 
     def parseConfigurationFiles(self, files):
-        def _parse(f, data, include=False):
-            try:
-                return bb.parse.handle(f, data, include)
-            except (IOError, bb.parse.ParseError) as exc:
-                parselog.critical("Unable to parse %s: %s" % (f, exc))
-                sys.exit(1)
-
         data = self.configuration.data
         bb.parse.init_parser(data)
         for f in files:
@@ -671,9 +665,9 @@ class BBCooker:
         data = _parse(os.path.join("conf", "bitbake.conf"), data)
 
         # Handle any INHERITs and inherit the base class
-        inherits  = ["base"] + (data.getVar('INHERIT', True) or "").split()
-        for inherit in inherits:
-            data = _parse(os.path.join('classes', '%s.bbclass' % inherit), data, True)
+        bbclasses  = ["base"] + (data.getVar('INHERIT', True) or "").split()
+        for bbclass in bbclasses:
+            data = _inherit(bbclass, data)
 
         # Nomally we only register event handlers at the end of parsing .bb files
         # We register any handlers we've found so far here...
@@ -1123,6 +1117,26 @@ class CookerExit(bb.event.Event):
     def __init__(self):
         bb.event.Event.__init__(self)
 
+def catch_parse_error(func):
+    """Exception handling bits for our parsing"""
+    @wraps(func)
+    def wrapped(fn, *args):
+        try:
+            return func(fn, *args)
+        except (IOError, bb.parse.ParseError, bb.data_smart.ExpansionError) as exc:
+            parselog.critical("Unable to parse %s: %s" % (fn, exc))
+            sys.exit(1)
+    return wrapped
+
+@catch_parse_error
+def _parse(fn, data, include=False):
+    return bb.parse.handle(fn, data, include)
+
+@catch_parse_error
+def _inherit(bbclass, data):
+    bb.parse.BBHandler.inherit([bbclass], data)
+    return data
+
 class ParsingFailure(Exception):
     def __init__(self, realexception, recipe):
         self.realexception = realexception