Fix android_finder.py

runtime/tools/utils.py

 # Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # This file contains a set of utilities functions used by other Python-based
 # scripts.
 
 import commands
 import os
 import platform
@@ skipping 149 matching lines @@
     errStream: if present, the stderr output of the command will be written to
         errStream.
     killOnEarlyReturn: if true and pollFn returns true, then the subprocess will
         be killed, otherwise the subprocess will be detached.
     verbose: if true, the command is echoed to stderr.
     debug: if true, prints debugging information to stderr.
     printErrorInfo: if true, prints error information when the subprocess
     returns a non-zero exit code.
   Returns: the output of the subprocess.
 
-  Raises an exception if the subprocess returns an error code.
+  Exceptions:
+    Raises Error if the subprocess returns an error code.
+    Raises ValueError if called with invalid arguments.
   """
   if verbose:
     sys.stderr.write("command %s\n" % command)
   stdin = None
-  if input is not None:
+  if input:
     stdin = subprocess.PIPE
   try:
     process = subprocess.Popen(args=command,
                                stdin=stdin,
                                bufsize=1,
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE)
-  except Exception as e:
+  except OSError as e:
     if not isinstance(command, basestring):
       command = ' '.join(command)
     if printErrorInfo:
       sys.stderr.write("Command failed: '%s'\n" % command)
-    raise e
+    raise Error(e)
 
   def StartThread(out):
     queue = Queue.Queue()
     def EnqueueOutput(out, queue):
       for line in iter(out.readline, b''):
         queue.put(line)
       out.close()
     thread = threading.Thread(target=EnqueueOutput, args=(out, queue))
     thread.daemon = True
     thread.start()
     return queue
   outQueue = StartThread(process.stdout)
   errQueue = StartThread(process.stderr)
 
   def ReadQueue(queue, out, out2):
     try:
       while True:
         line = queue.get(False)
         out.write(line)
         if out2 != None:
           out2.write(line)
     except Queue.Empty:
       pass
 
   outBuf = StringIO.StringIO()
   errorBuf = StringIO.StringIO()
-  if input != None:
+  if input:
     process.stdin.write(input)
   while True:
     returncode = process.poll()
     if returncode != None:
       break
     ReadQueue(errQueue, errorBuf, errStream)
     ReadQueue(outQueue, outBuf, outStream)
     if pollFn != None and pollFn():
       returncode = 0
       if killOnEarlyReturn:
         process.kill()
       break
     time.sleep(0.1)
   # Drain queue
   ReadQueue(errQueue, errorBuf, errStream)
   ReadQueue(outQueue, outBuf, outStream)
 
   out = outBuf.getvalue();
   error = errorBuf.getvalue();
-  if returncode != 0:
+  if returncode:
     if not isinstance(command, basestring):
       command = ' '.join(command)
     if printErrorInfo:
       sys.stderr.write("Command failed: '%s'\n" % command)
       sys.stderr.write("        stdout: '%s'\n" % out)
       sys.stderr.write("        stderr: '%s'\n" % error)
       sys.stderr.write("    returncode: %d\n" % returncode)
-    raise Exception("Command failed: %s" % command)
+    raise Error("Command failed: %s" % command)
   if debug:
     sys.stderr.write("output: %s\n" % out)
   return out
 
 
 def Main(argv):
   print "GuessOS() -> ", GuessOS()
   print "GuessArchitecture() -> ", GuessArchitecture()
   print "GuessCpus() -> ", GuessCpus()
   print "IsWindows() -> ", IsWindows()
 
 
+class Error(Exception):
+  pass
+
+
 if __name__ == "__main__":
   import sys
   Main(sys.argv)