[U-Boot] [[RFC Patch] 2/2] tools: buildman: Add compiler wrapper

[York Sun]

Now we can use compiler wrapper such as ccache or distcc for buildman.

Signed-off-by: York Sun <york.sun at nxp.com>
CC: Simon Glass <sjg at chromium.org>
---
This is not perfect and may need some improvement. Something I didn't figure
out is how to drop the name under [toolchain-wrapper]. I intended to have this
format but bsettings.GetItems doesn't like it.

[toolchain-wrapper]
ccache

It doesn't deal with more than one line for this setting. For now, the last
setting is taken.

 tools/buildman/README       |  9 +++++++++
 tools/buildman/toolchain.py | 17 +++++++++++++++--
 2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/tools/buildman/README b/tools/buildman/README
index 8c5f861..514bebc 100644
--- a/tools/buildman/README
+++ b/tools/buildman/README
@@ -211,6 +211,15 @@ arm: arm-none-eabi-
 
 and buildman will find arm-none-eabi-gcc in /usr/bin if you have it installed.
 
+[toolchain-wrapper]
+wrapper: ccache
+
+This tells buildman to use a compiler wrapper in front of CROSS_COMPILE. In
+this example, ccache. It doesn't affect the toolchain scan. The wrapper is
+added when CROSS_COMPILE environtal variable is set. The name in this
+section is ignored. If more than one line is provided, only the last one
+is taken.
+
 3. Make sure you have the require Python pre-requisites
 
 Buildman uses multiprocessing, Queue, shutil, StringIO, ConfigParser and
diff --git a/tools/buildman/toolchain.py b/tools/buildman/toolchain.py
index 41e4e4c..01cdb03 100644
--- a/tools/buildman/toolchain.py
+++ b/tools/buildman/toolchain.py
@@ -127,6 +127,15 @@ class Toolchain:
                 return PRIORITY_CALC + prio
         return PRIORITY_CALC + prio
 
+    def GetWrapper(self, show_warning=True):
+        """Get toolchain wrapper from the setting file.
+        """
+	value = ''
+	for name, value in bsettings.GetItems('toolchain-wrapper'):
+            if not value:
+                print "Warning: Wrapper not found"
+        return value
+
     def MakeEnvironment(self, full_path):
         """Returns an environment for using the toolchain.
 
@@ -138,10 +147,14 @@ class Toolchain:
                 PATH
         """
         env = dict(os.environ)
+        wrapper = self.GetWrapper()
+        if wrapper:
+            wrapper = wrapper + ' '
+
         if full_path:
-            env['CROSS_COMPILE'] = os.path.join(self.path, self.cross)
+            env['CROSS_COMPILE'] = wrapper + os.path.join(self.path, self.cross)
         else:
-            env['CROSS_COMPILE'] = self.cross
+            env['CROSS_COMPILE'] = wrapper + self.cross
             env['PATH'] = self.path + ':' + env['PATH']
 
         return env
-- 
2.7.4