Use a runtime check to see if http://bugs.python.org/issue5380 is fixed.

svn path=/main/trunk/; revision=14413

diff --git a/pym/portage/__init__.py b/pym/portage/__init__.py
index 2b6d937cc7513f5cc98f9577a137bb5acf2753cd..e04e37a828cb78a2af705e9feb11b18d7cb063f4 100644 (file)
--- a/pym/portage/__init__.py
+++ b/pym/portage/__init__.py
@@ -3739,13 +3739,65 @@ class config(object):
                keys = __iter__
                items = iteritems
 
+def _test_pty_eof():
+       """
+       Returns True if this issues is fixed for the currently
+       running version of python: http://bugs.python.org/issue5380
+       """
+
+       import array, pty, termios
+       test_string = 2 * "blah blah blah\n"
+       test_string = _unicode_decode(test_string,
+               encoding='utf_8', errors='strict')
+
+       try:
+               master_fd, slave_fd = pty.openpty()
+       except EnvironmentError:
+               return False
+
+       master_file = os.fdopen(master_fd, 'rb')
+       slave_file = os.fdopen(slave_fd, 'wb')
+
+       # Disable post-processing of output since otherwise weird
+       # things like \n -> \r\n transformations may occur.
+       mode = termios.tcgetattr(slave_fd)
+       mode[1] &= ~termios.OPOST
+       termios.tcsetattr(slave_fd, termios.TCSANOW, mode)
+
+       # Simulate a subprocess writing some data to the
+       # slave end of the pipe, and then exiting.
+       slave_file.write(_unicode_encode(test_string,
+               encoding='utf_8', errors='strict'))
+       slave_file.close()
+
+       eof = False
+       data = []
+
+       while not eof:
+
+               buf = array.array('B')
+               try:
+                       buf.fromfile(master_file, 1024)
+               except EOFError:
+                       eof = True
+               except IOError:
+                       # This is where data loss occurs.
+                       eof = True
+
+               if not buf:
+                       eof = True
+               else:
+                       data.append(_unicode_decode(buf.tostring(),
+                               encoding='utf_8', errors='strict'))
+
+       master_file.close()
+
+       return test_string == ''.join(data)
+
 # In some cases, openpty can be slow when it fails. Therefore,
 # stop trying to use it after the first failure.
 _disable_openpty = False
-
-if sys.hexversion >= 0x3000000:
-       # This is a temporary workaround for http://bugs.python.org/issue5380.
-       _disable_openpty = True
+_tested_pty = False
 
 def _create_pty_or_pipe(copy_term_size=None):
        """
@@ -3763,7 +3815,12 @@ def _create_pty_or_pipe(copy_term_size=None):
 
        got_pty = False
 
-       global _disable_openpty
+       global _disable_openpty, _tested_pty
+       if not _tested_pty:
+               if not _test_pty_eof():
+                       _disable_openpty = True
+               _tested_pty = True
+
        if _disable_openpty:
                master_fd, slave_fd = os.pipe()
        else: