Handle keyboard interrupt during build

lib/webports/source_package.py

 # Copyright (c) 2014 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import contextlib
 import fnmatch
 import os
 import re
 import subprocess
 import sys
@@ skipping 347 matching lines @@
           old_log_level = util.log_level
           util.log_level = util.LOG_VERBOSE
           try:
             self.Download()
             self.Extract()
             self.Patch()
             self.RunBuildSh()
             self.CreatePkgFile()
           finally:
             util.log_level = old_log_level
+      except KeyboardInterrupt:
+        # Treat KeyboardInterrupt as special, and not an actual failure.  This
+        # avoid log spew to stdout when they user interupts a quit build.
+        raise
       except:
         if log_filename:
           with open(log_filename) as log_file:
             sys.stdout.write(log_file.read())
         raise
 
     duration = FormatTimeDelta(time.time() - start)
     util.LogHeading('Build complete', ' [took %s]' % duration)
 
   def RunBuildSh(self):
@@ skipping 410 matching lines @@
   if os.path.isdir(package_name):
     return SourcePackage(package_name, config)
 
   for subdir in DEFAULT_LOCATIONS:
     pkg_root = os.path.join(paths.NACLPORTS_ROOT, subdir, package_name)
     info = os.path.join(pkg_root, 'pkg_info')
     if os.path.exists(info):
       return SourcePackage(pkg_root, config)
 
   raise Error("Package not found: %s" % package_name)