[PATCH] Add FAKEROOTNOENV variable

[Richard Purdie <richard.purdie@linuxfoundation.org>]

Add a FAKEROOTNOENV which does the opposite of the FAKEROOTENV variable
and is data loaded into the environment for tasks without the fakeroot
flag. 

The intent here is to provide a way to control the environment when we
aren't needing fakeroot context which allows us to unload the preload
from memory entirely and gain a valuable speedup.

I'm not 100% happy with needing this at the bitbake level, particularly
with the cache hit but it does give a valuable speedup.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/lib/bb/cache.py b/lib/bb/cache.py
index d495f9e..fe35e13 100644
--- a/lib/bb/cache.py
+++ b/lib/bb/cache.py
@@ -143,6 +143,7 @@ class CoreRecipeInfo(RecipeInfoCommon):
         self.section          = self.getvar('SECTION', metadata)
         self.fakerootenv      = self.getvar('FAKEROOTENV', metadata)
         self.fakerootdirs     = self.getvar('FAKEROOTDIRS', metadata)
+        self.fakerootnoenv    = self.getvar('FAKEROOTNOENV', metadata)
 
     @classmethod
     def init_cacheData(cls, cachedata):
@@ -178,6 +179,7 @@ class CoreRecipeInfo(RecipeInfoCommon):
         cachedata.license = {}
         cachedata.section = {}
         cachedata.fakerootenv = {}
+        cachedata.fakerootnoenv = {}
         cachedata.fakerootdirs = {}
 
     def add_cacheData(self, cachedata, fn):
@@ -243,6 +245,7 @@ class CoreRecipeInfo(RecipeInfoCommon):
         cachedata.license[fn] = self.license
         cachedata.section[fn] = self.section
         cachedata.fakerootenv[fn] = self.fakerootenv
+        cachedata.fakerootnoenv[fn] = self.fakerootnoenv
         cachedata.fakerootdirs[fn] = self.fakerootdirs
 
 
diff --git a/lib/bb/runqueue.py b/lib/bb/runqueue.py
index 9a1bad7..7a39d89 100644
--- a/lib/bb/runqueue.py
+++ b/lib/bb/runqueue.py
@@ -1096,6 +1096,12 @@ class RunQueueExecute:
 
             logger.debug(2, 'Running %s:%s under fakeroot, fakedirs: %s' %
                             (fn, taskname, ', '.join(fakedirs)))
+        else:
+            envvars = (self.rqdata.dataCache.fakerootnoenv[fn] or "").split()
+            for key, value in (var.split('=') for var in envvars):
+                envbackup[key] = os.environ.get(key)
+                os.environ[key] = value
+                fakeenv[key] = value
 
         sys.stdout.flush()
         sys.stderr.flush()