Make this file mostly conformant with gpylint. There should be no semantic

consequences.

TESTS: make distcheck
REVIEWER: fergus@google.com


git-svn-id: http://distcc.googlecode.com/svn/trunk@134 01de4be4-8c4a-0410-9132-4925637da917

1 files changed, 134 insertions, 112 deletions

diff --git a/include_server/basics.py b/include_server/basics.py
index a6aa5bf..c23c7be 100755
--- a/include_server/basics.py
+++ b/include_server/basics.py
@@ -1,4 +1,4 @@
-#! /usr/bin/python2.4
+#!/usr/bin/python2.4
 #
 # Copyright 2007 Google Inc.
 # 
@@ -16,16 +16,17 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 #
-
+#
 """Common and low-level stuff for include server."""
 
-__author__ = "Nils Klarlund"
+__author__ = 'Nils Klarlund'
 
-import sys
-import tempfile
 import os.path
-import signal
 import resource
+import signal
+import sys
+import tempfile
+
 
 # MISCELLANEOUS CONSTANTS
 
@@ -35,32 +36,34 @@ client_tmp = None
 client_root = None
 
 # This constant is embedded in names of client root directories.
-INCLUDE_SERVER_NAME = "include_server"
+INCLUDE_SERVER_NAME = 'include_server'
+
 
 def InitializeClientTmp():
   """Determine the tmp directory to use.
 
   Use the RAM disk-like /dev/shm as default place to store compressed files if
-  available."""
+  available.
+  """
 
   global client_tmp
-  if "DISTCC_CLIENT_TMP" in os.environ:
-    client_tmp = os.environ["DISTCC_CLIENT_TMP"]
-  elif os.path.isdir("/dev/shm") and os.access("/dev/shm", 
-                                             os.X_OK + os.W_OK + os.R_OK):
-    client_tmp = "/dev/shm"
+  if 'DISTCC_CLIENT_TMP' in os.environ:
+    client_tmp = os.environ['DISTCC_CLIENT_TMP']
+  elif os.path.isdir('/dev/shm') and os.access('/dev/shm',
+                                               os.X_OK + os.W_OK + os.R_OK):
+    client_tmp = '/dev/shm'
   else:
-    client_tmp = "/tmp"
+    client_tmp = '/tmp'
   if not client_tmp or client_tmp[0] != '/':
-    sys.exit("DISTCC_CLIENT_TMP must start with '/'.")
+    sys.exit("""DISTCC_CLIENT_TMP must start with '/'.""")
   client_tmp = client_tmp.rstrip('/')
   # The protocol between the include server and distcc client stipulates
   # that the top three directories constitute the prefix prepended to absolute
   # file paths. To have room to make a temp directory, we'll need to have less
   # than two levels at this point.
-  # Note: "/a/b".split('/') == ["", "a", "b'].
+  # Note: '/a/b'.split('/') == ['', 'a', 'b'].
   if len(client_tmp.split('/')) > 3:
-    sys.exit("DISTCC_CLIENT_TMP must have at most two directory levels.")
+    sys.exit('DISTCC_CLIENT_TMP must have at most two directory levels.')
 
 
 def InitializeClientRoot(generation):
@@ -75,24 +78,24 @@ def InitializeClientRoot(generation):
   try:
     # Create a unique identifier that will never repeat. Use pid as suffix for
     # cleanout mechanism that wipes files not associated with a running pid.
-    client_root = tempfile.mkdtemp(".%s-%s-%d" %
+    client_root = tempfile.mkdtemp('.%s-%s-%d' %
                                    (INCLUDE_SERVER_NAME,
                                     os.getpid(), generation),
                                    dir=client_tmp)
     number_missing_levels = 3 - len(client_tmp.split('/'))
     # Stuff client_root path until we have exactly three levels in all.
-    for i in range(number_missing_levels):
-      client_root = client_root + "/padding"
+    for unused_i in range(number_missing_levels):
+      client_root += '/padding'
       os.mkdir(client_root)
   except (IOError, OSError), why:
-      sys.exit("Could not create client root directory %s: %s" %
-               (client_root, why))
+    sys.exit('Could not create client root directory %s: %s' %
+             (client_root, why))
       
 
 # For automated emails, see also src/emaillog.h.
-DCC_EMAILLOG_WHOM_TO_BLAME = os.getenv("DISTCC_EMAILLOG_WHOM_TO_BLAME",
-                                       "distcc-pump-errors") 
-EMAIL_SUBJECT = "distcc-pump include server email"
+DCC_EMAILLOG_WHOM_TO_BLAME = os.getenv('DISTCC_EMAILLOG_WHOM_TO_BLAME',
+                                       'distcc-pump-errors')
+EMAIL_SUBJECT = 'distcc-pump include server email'
 CANT_SEND_MESSAGE = """Please notify %s that the distcc-pump include server
 tried to send them email but failed.""" % DCC_EMAILLOG_WHOM_TO_BLAME
 MAX_EMAILS_TO_SEND = 3
@@ -116,18 +119,18 @@ USER_TIME_QUOTA_CHECK_INTERVAL_TIME = 4  # seconds, an integer
 
 # ALGORITHMS
 
-SIMPLE = 0 # not implemented
-MEMOIZING = 1 # only one currently implemented
-ALGORITHMS = [ SIMPLE, MEMOIZING ]
+SIMPLE = 0     # not implemented
+MEMOIZING = 1  # only one currently implemented
+ALGORITHMS = [SIMPLE, MEMOIZING]
 
 
 # FLAGS FOR COMMAND LINE OPTIONS
 
-opt_debug_pattern = 1 # see DEBUG below
-opt_verify = False # whether to compare calculated include closure to that
-                   # produced by compiler
-opt_exact_analysis = False # use CPP instead of include analyzer
-opt_write_include_closure = False # write include closures to file
+opt_debug_pattern = 1  # see DEBUG below
+opt_verify = False     # whether to compare calculated include closure to that
+                       # produced by compiler
+opt_exact_analysis = False         # use CPP instead of include analyzer
+opt_write_include_closure = False  # write include closures to file
 opt_statistics = False
 opt_algorithm = MEMOIZING
 opt_stat_reset_triggers = {}
@@ -140,6 +143,7 @@ opt_realpath_warning_re = None
 
 # HELPER FUNCTION FOR STAT_RESET_TRIGGERS
 
+
 def Stamp(path):
   """Return a stamp characterizing a file and its modification time."""
   try:
@@ -153,40 +157,37 @@ def Stamp(path):
 # REALPATH WARNINGS
 
 BAD_REALPATH_WARNING_MSG = (
-  "For translation unit '%s' while processing '%s': lookup of file '%s' "
-  + "resolved to '%s' whose realpath is '%s'.")
+    """For translation unit '%s' while processing '%s': lookup of file '%s' """
+    """resolved to '%s' whose realpath is '%s'.""")
 
 
 # LANGUAGES AND FILE EXTENSIONS
 
 # The languages that we recognize.
 #
-# TODO: add "objective-c" and "objective-c++".
-# Currently we try to compute the default include path for all
-# languages at startup, and barf if it fails.  We need to fix that
-# before enabling objective-c or objective-c++.
-# So Objective C and Objective C++ support is disabled for now.
+# TODO(klarlund): add "objective-c" and "objective-c++".  Currently we try to
+# compute the default include path for all languages at startup, and barf if it
+# fails.  We need to fix that before enabling objective-c or objective-c++.  So
+# Objective C and Objective C++ support is disabled for now.
 #
-# (Also, I couldn't test the Objective C++ case, because I couldn't figure
-# out how to install GNU Objective C++.  We need to test it before
-# enabling it.)
 # To enable, uncomment the code below and the test case
 # ObjectiveC(PlusPlus)_Case in ../test/testdistcc.py.)
 
-LANGUAGES = set(["c", "c++"])
-#LANGUAGES = set(["c", "c++", "objective-c", "objective-c++"])
+LANGUAGES = set(['c', 'c++'])
+#LANGUAGES = set(['c', 'c++', 'objective-c', 'objective-c++'])
 
 # The suffixes, following last period, used for source files and
 # preprocessed files, each with their corresponding source language.
 TRANSLATION_UNIT_MAP = {
     # C
-    "c":"c", "i":"c",
+    'c': 'c', 'i': 'c',
     # C++
-    "cc":"c++", "cpp":"c++", "cxx":"c++", "C":"c++", "CXX":"c++", "ii":"c++",
+    'cc': 'c++', 'cpp': 'c++', 'cxx': 'c++', 'C': 'c++', 'CXX': 'c++',
+    'ii': 'c++',
     # Objective C
-    # "m":"objective-c", "mi":"objective-c"
+    # 'm': 'objective-c', 'mi': 'objective-c'
     # Objective C++
-    # "mm":"objective-c++", "M":"objective-c++", "mii":"objective-c++",
+    # 'mm': 'objective-c++', 'M': 'objective-c++', 'mii': 'objective-c++',
     }
 
 # All languages are described by suffixes.
@@ -197,102 +198,115 @@ assert set(TRANSLATION_UNIT_MAP.values()) == LANGUAGES
 
 # Debugging is controlled by the 5 least significant bits of
 # opt_debug_pattern.
-DEBUG_WARNING = 1  # For warnings
-DEBUG_TRACE =  2   # For tracing functions (upper level)
-DEBUG_TRACE1 = 4   # For tracing functions (medium level)
-DEBUG_TRACE2 = 8   # For tracing functions (lower level)
-DEBUG_DATA = 16    # For printing data
-DEBUG_NUM_BITS = 5 # The cardinality of {1,2,4,8,16}
+DEBUG_WARNING = 1   # For warnings
+DEBUG_TRACE = 2     # For tracing functions (upper level)
+DEBUG_TRACE1 = 4    # For tracing functions (medium level)
+DEBUG_TRACE2 = 8    # For tracing functions (lower level)
+DEBUG_DATA = 16     # For printing data
+DEBUG_NUM_BITS = 5  # The cardinality of {1,2,4,8,16}
+
 
 def Debug(trigger_pattern, message, *params):
+  """Print message to stderr depending on trigger pattern.
+
+  Args:
+    trigger_pattern: a bit vector (as an integer)
+    message: a format string
+    params: arguments to message
+  """
+  # TODO(klarlund): use Python's logging module.
   triggered = opt_debug_pattern & trigger_pattern
   if triggered:
     i = 1
     for unused_j in range(DEBUG_NUM_BITS):
       if i & DEBUG_WARNING & triggered:
-	print >> sys.stderr, "WARNING include server:", message % params
+        print >> sys.stderr, 'WARNING include server:', message % params
       if i & DEBUG_TRACE & triggered:
-	print >> sys.stderr, "TRACE:", message % params
+        print >> sys.stderr, 'TRACE:', message % params
       elif i & DEBUG_TRACE1 & triggered:
-	print >> sys.stderr, "TRACE1:", message % params
+        print >> sys.stderr, 'TRACE1:', message % params
       elif i & DEBUG_TRACE2 & triggered:
-	print >> sys.stderr, "TRACE2:", message % params
+        print >> sys.stderr, 'TRACE2:', message % params
       elif i & DEBUG_DATA & triggered:
-	print >> sys.stderr, "DATA:", message % params
+        print >> sys.stderr, 'DATA:', message % params
       i *= 2
     sys.stderr.flush()
 
 
 # EXCEPTIONS
 
+
 class Error(Exception):
+  """For include server errors."""
   pass
 
+
 class NotCoveredError(Error):
-    """Exception for included file not covered by include processing."""
-
-    def __init__(self, message,
-                 source_file=None,
-                 line_number=None,
-                 send_email=True):
-      """Constructor.
-
-      Arguments:
-        message: text of error message
-        source_file: name of source_file if known
-        line_number: an integer, if known
-        send_email: a Boolean, if False then never send email
-
-      These arguments are all stored in the exception. However, the source_file
-      and line_number are appended, in a syntax defined here, to the message
-      before it is stored as self.args[0] through invocation of the Error
-      constructor."""
-      assert not line_number or source_file
-      self.source_file = None
-      self.line_number = None
-      self.send_email = send_email
-      if source_file:
-        # Mark this exception as mentioning the source_file.
-        self.source_file = source_file
-        # Line numbers are not currently used.
-        if line_number:
-          self.line_number = line_number
-          message = "File: '%s', line: %s: %s" % (
-            source_file, line_number, message)
-        else:
-          message = "File: '%s': %s" % (source_file, message)
-      # Message, a string, becomes self.args[0]    
-      Error.__init__(self, message)
+  """Exception for included file not covered by include processing."""
+
+  def __init__(self, message,
+               source_file=None,
+               line_number=None,
+               send_email=True):
+    """Constructor.
+
+    Arguments:
+      message: text of error message
+      source_file: name of source_file if known
+      line_number: an integer, if known
+      send_email: a Boolean, if False then never send email
+
+    These arguments are all stored in the exception. However, the source_file
+    and line_number are appended, in a syntax defined here, to the message
+    before it is stored as self.args[0] through invocation of the Error
+    constructor.
+    """
+    assert not line_number or source_file
+    self.source_file = None
+    self.line_number = None
+    self.send_email = send_email
+    if source_file:
+      # Mark this exception as mentioning the source_file.
+      self.source_file = source_file
+      # Line numbers are not currently used.
+      if line_number:
+        self.line_number = line_number
+        message = ("""File: '%s', line: %s: %s"""
+                   % (source_file, line_number, message))
+      else:
+        message = """File: '%s': %s""" % (source_file, message)
+    # Message, a string, becomes self.args[0]    
+    Error.__init__(self, message)
 
 
 class NotCoveredTimeOutError(NotCoveredError):
-  """An instance of this class is raised when the include server has spent too
-  much time analyzing dependencies."""
+  """Raised when spending too much time analyzing dependencies."""
   pass
 
 
 class IncludeAnalyzerTimer(object):
-  """Start a timer that limits the amount of CPU time the include analyzer may
-  spend servicing a single request.
+  """Start a timer limiting CPU time for servicing a single request.
 
   We use user time so that a network hiccup will not entail a cache reset if,
   say, we are using NFS.
 
-  An object of this class must be instantiated so that, no matter what, the Cancel
-  method is eventually called. This reinstates the original timer (if present).
+  An object of this class must be instantiated so that, no matter what, the
+  Cancel method is eventually called. This reinstates the original timer (if
+  present).
   """
+
   def __init__(self):
     self.start_utime = resource.getrusage(resource.RUSAGE_SELF).ru_utime
     self.old = signal.signal(signal.SIGALRM, self._TimeIsUp)
     signal.alarm(USER_TIME_QUOTA_CHECK_INTERVAL_TIME)
 
-  def _TimeIsUp(self, _sig_number, _frame):
+  def _TimeIsUp(self, unused_sig_number, unused_frame):
     """Check CPU time spent and raise exception or reschedule."""
     if (resource.getrusage(resource.RUSAGE_SELF).ru_utime
         > self.start_utime + USER_TIME_QUOTA):
-      raise NotCoveredTimeOutError(("Bailing out because include server "
-                                    + "spent more than %3.1fs user time "
-                                    + "handling request") %
+      raise NotCoveredTimeOutError(('Bailing out because include server '
+                                    + 'spent more than %3.1fs user time '
+                                    + 'handling request') %
                                    USER_TIME_QUOTA)
     else:
       # Reschedule ourselves.
@@ -305,7 +319,7 @@ class IncludeAnalyzerTimer(object):
     signal.alarm(USER_TIME_QUOTA_CHECK_INTERVAL_TIME)
 
   def Cancel(self):
-    """Must be called eventually.  See class documentation."""
+    """Must be called eventually. See class documentation."""
     sys.stdout.flush()
     signal.alarm(0)
     signal.signal(signal.SIGALRM, self.old)
@@ -315,25 +329,33 @@ class SignalSIGTERM(Error):
   pass
 
 
-def RaiseSignalSIGTERM(*_args):
+def RaiseSignalSIGTERM(*unused_args):
   """Raise SignalSIGTERM.
 
   Use signal.signal for binding this function to SIGTERM.
-  """  
+  """
   raise SignalSIGTERM
 
 
 # COMMON FUNCTIONS
 
+
 def SafeNormPath(path):
   """Safe, but limited, version of os.path.normpath.
 
+  Args:
+    path: a string
+
+  Returns:
+    a string
+    
   Python's os.path.normpath is an unsafe operation; the result may not point to
   the same file as the argument. Instead, this function just removes
-  initial './'s and a final '/'s if present."""
-  if path == ".":
-    return ""
+  initial './'s and a final '/'s if present.
+  """
+  if path == '.':
+    return ''
   else:
-    while path.startswith("./"):
+    while path.startswith('./'):
       path = path[2:]
-    return path.rstrip("/")
+    return path.rstrip('/')