Merge pull request #696 from jerynmathew/fix/693-config-pyc

Fix for #693

gunicorn/six.py

@@ -286,6 +286,63 @@ def StringIO(buf=''):
 _add_doc(u, """Text literal""")
 
 
+def _check_if_pyc(fname):
+    """ Returns True if the extension is .pyc, False if .py and None if otherwise """
+    from imp import find_module
+    from os.path import realpath, dirname, basename, splitext
+
+    # Normalize the file-path for the find_module()
+    filepath = realpath(fname)
+    dirpath = dirname(filepath)
+    module_name = splitext(basename(filepath))[0]
+
+    # Validate and fetch
+    try:
+        fileobj, fullpath, (_, _, pytype) = find_module(module_name, [ dirpath ])
+
+    except ImportError:
+        raise IOError("Cannot find config file. Path maybe incorrect! : {0}".format(filepath))
+
+    return (pytype, fileobj, fullpath)
+
+
+def _get_codeobj(pyfile):
+    """ Returns the code object, given a python file """
+    from imp import PY_COMPILED, PY_SOURCE
+
+    result, fileobj, fullpath = _check_if_pyc(pyfile)
+
+    # WARNING:
+    # fp.read() can blowup if the module is extremely large file.
+    # Lookout for overflow errors.
+    try:
+        data = fileobj.read()
+    finally:
+        fileobj.close()
+
+    # This is a .pyc file. Treat accordingly.
+    if result is PY_COMPILED:
+        # .pyc format is as follows:
+        # 0 - 4 bytes: Magic number, which changes with each create of .pyc file.
+        #              First 2 bytes change with each marshal of .pyc file. Last 2 bytes is "\r\n".
+        # 4 - 8 bytes: Datetime value, when the .py was last changed.
+        # 8 - EOF: Marshalled code object data.
+        # So to get code object, just read the 8th byte onwards till EOF, and UN-marshal it.
+        import marshal
+        code_obj = marshal.loads(data[8:])
+
+    elif result is PY_SOURCE:
+        # This is a .py file.
+        code_obj = compile(data, fullpath, 'exec')
+
+    else:
+        # Unsupported extension
+        raise Exception("Input file is unknown format: {0}".format(fullpath))
+
+    # Return code object
+    return code_obj
+
+
 if PY3:
 
     import builtins
@@ -300,7 +357,7 @@ def reraise(tp, value, tb=None):
     print_ = getattr(builtins, "print")
 
     def execfile_(fname, *args):
-        return exec_(compile(open(fname, 'rb').read(), fname, 'exec'), *args)
+        return exec_(_get_codeobj(fname), *args)
 
 
     del builtins
@@ -323,7 +380,10 @@ def exec_(code, globs=None, locs=None):
     raise tp, value, tb
 """)
 
-    execfile_ = execfile
+    def execfile_(fname, *args):
+        """ Overriding PY2 execfile() implementation to support .pyc files """
+        return exec_(_get_codeobj(fname), *args)
+
 
     def print_(*args, **kwargs):
         """The new-style print function."""