Rename C accelerator modules to avoid clashes.

Fixes #1480.

docs/changes/1480.bugfix

+Rename gevent's C accelerator extension modules using a prefix to
+avoid clashing with other C extensions.

setup.py

@@ -48,81 +48,89 @@ from _setupares import ARES
 
 CORE = cythonize1(build_libev_extension())
 
-# Get access to the greenlet header file.
-
-SEMAPHORE = Extension(name="gevent.__semaphore",
+# Modules that we cythonize for performance.
+# Be careful not to use simple names for these modules,
+# as the non-static symbols cython generates do not include
+# the module name. Thus an extension of 'gevent._queue'
+# results in symbols like 'PyInit__queue', which is the same
+# symbol used by the standard library _queue accelerator module.
+# The name of the .pxd file must match the local name of the accelerator
+# extension; however, sadly, the generated .c and .html files will
+# still use the same name as the .py source.
+
+SEMAPHORE = Extension(name="gevent._gevent_c_semaphore",
                       sources=["src/gevent/_semaphore.py"],
-                      depends=['src/gevent/__semaphore.pxd'],
+                      depends=['src/gevent/_gevent_c_semaphore.pxd'],
                       include_dirs=get_include_dirs())
 
 
-LOCAL = Extension(name="gevent._local",
+LOCAL = Extension(name="gevent._gevent_clocal",
                   sources=["src/gevent/local.py"],
-                  depends=['src/gevent/_local.pxd'],
+                  depends=['src/gevent/_gevent_clocal.pxd'],
                   include_dirs=get_include_dirs())
 
 
-GREENLET = Extension(name="gevent._greenlet",
+GREENLET = Extension(name="gevent._gevent_cgreenlet",
                      sources=[
                          "src/gevent/greenlet.py",
                      ],
                      depends=[
-                         'src/gevent/_greenlet.pxd',
-                         'src/gevent/__ident.pxd',
+                         'src/gevent/_gevent_cgreenlet.pxd',
+                         'src/gevent/_gevent_c_ident.pxd',
                          'src/gevent/_ident.py'
                      ],
                      include_dirs=get_include_dirs())
 
-ABSTRACT_LINKABLE = Extension(name="gevent.__abstract_linkable",
+ABSTRACT_LINKABLE = Extension(name="gevent._gevent_c_abstract_linkable",
                               sources=["src/gevent/_abstract_linkable.py"],
-                              depends=['src/gevent/__abstract_linkable.pxd'],
+                              depends=['src/gevent/_gevent_c_abstract_linkable.pxd'],
                               include_dirs=get_include_dirs())
 
 
-IDENT = Extension(name="gevent.__ident",
+IDENT = Extension(name="gevent._gevent_c_ident",
                   sources=["src/gevent/_ident.py"],
-                  depends=['src/gevent/__ident.pxd'],
+                  depends=['src/gevent/_gevent_c_ident.pxd'],
                   include_dirs=get_include_dirs())
 
 
-IMAP = Extension(name="gevent.__imap",
+IMAP = Extension(name="gevent._gevent_c_imap",
                  sources=["src/gevent/_imap.py"],
-                 depends=['src/gevent/__imap.pxd'],
+                 depends=['src/gevent/_gevent_c_imap.pxd'],
                  include_dirs=get_include_dirs())
 
-EVENT = Extension(name="gevent._event",
+EVENT = Extension(name="gevent._gevent_cevent",
                   sources=["src/gevent/event.py"],
-                  depends=['src/gevent/_event.pxd'],
+                  depends=['src/gevent/_gevent_cevent.pxd'],
                   include_dirs=get_include_dirs())
 
-QUEUE = Extension(name="gevent._queue",
+QUEUE = Extension(name="gevent._gevent_cqueue",
                   sources=["src/gevent/queue.py"],
-                  depends=['src/gevent/_queue.pxd'],
+                  depends=['src/gevent/_gevent_cqueue.pxd'],
                   include_dirs=get_include_dirs())
 
-HUB_LOCAL = Extension(name="gevent.__hub_local",
+HUB_LOCAL = Extension(name="gevent._gevent_c_hub_local",
                       sources=["src/gevent/_hub_local.py"],
-                      depends=['src/gevent/__hub_local.pxd'],
+                      depends=['src/gevent/_gevent_c_hub_local.pxd'],
                       include_dirs=get_include_dirs())
 
-WAITER = Extension(name="gevent.__waiter",
+WAITER = Extension(name="gevent._gevent_c_waiter",
                    sources=["src/gevent/_waiter.py"],
-                   depends=['src/gevent/__waiter.pxd'],
+                   depends=['src/gevent/_gevent_c_waiter.pxd'],
                    include_dirs=get_include_dirs())
 
-HUB_PRIMITIVES = Extension(name="gevent.__hub_primitives",
+HUB_PRIMITIVES = Extension(name="gevent._gevent_c_hub_primitives",
                            sources=["src/gevent/_hub_primitives.py"],
-                           depends=['src/gevent/__hub_primitives.pxd'],
+                           depends=['src/gevent/_gevent_c_hub_primitives.pxd'],
                            include_dirs=get_include_dirs())
 
-GLT_PRIMITIVES = Extension(name="gevent.__greenlet_primitives",
+GLT_PRIMITIVES = Extension(name="gevent._gevent_c_greenlet_primitives",
                            sources=["src/gevent/_greenlet_primitives.py"],
-                           depends=['src/gevent/__greenlet_primitives.pxd'],
+                           depends=['src/gevent/_gevent_c_greenlet_primitives.pxd'],
                            include_dirs=get_include_dirs())
 
-TRACER = Extension(name="gevent.__tracer",
+TRACER = Extension(name="gevent._gevent_c_tracer",
                    sources=["src/gevent/_tracer.py"],
-                   depends=['src/gevent/__tracer.pxd'],
+                   depends=['src/gevent/_gevent_c_tracer.pxd'],
                    include_dirs=get_include_dirs())
 
 

src/gevent/__abstract_linkable.pxd → src/gevent/_gevent_c_abstract_linkable.pxd

 cimport cython
 
-from gevent.__greenlet_primitives cimport SwitchOutGreenletWithLoop
-from gevent.__hub_local cimport get_hub_noargs as get_hub
+from gevent._gevent_c_greenlet_primitives cimport SwitchOutGreenletWithLoop
+from gevent._gevent_c_hub_local cimport get_hub_noargs as get_hub
 
 cdef InvalidSwitchError
 cdef Timeout

src/gevent/__hub_local.pxd → src/gevent/_gevent_c_hub_local.pxd

-from gevent.__greenlet_primitives cimport SwitchOutGreenletWithLoop
+from gevent._gevent_c_greenlet_primitives cimport SwitchOutGreenletWithLoop
 
 cdef _threadlocal
 

src/gevent/__hub_primitives.pxd → src/gevent/_gevent_c_hub_primitives.pxd

 cimport cython
 
-from gevent.__greenlet_primitives cimport SwitchOutGreenletWithLoop
-from gevent.__hub_local cimport get_hub_noargs as get_hub
+from gevent._gevent_c_greenlet_primitives cimport SwitchOutGreenletWithLoop
+from gevent._gevent_c_hub_local cimport get_hub_noargs as get_hub
 
-from gevent.__waiter cimport Waiter
-from gevent.__waiter cimport MultipleWaiter
+from gevent._gevent_c_waiter cimport Waiter
+from gevent._gevent_c_waiter cimport MultipleWaiter
 
 cdef InvalidSwitchError
 cdef _waiter

src/gevent/__imap.pxd → src/gevent/_gevent_c_imap.pxd

 cimport cython
-from gevent._greenlet cimport Greenlet
-from gevent.__semaphore cimport Semaphore
-from gevent._queue cimport UnboundQueue
+from gevent._gevent_cgreenlet cimport Greenlet
+from gevent._gevent_c_semaphore cimport Semaphore
+from gevent._gevent_cqueue cimport UnboundQueue
 
 @cython.freelist(100)
 @cython.internal

src/gevent/__semaphore.pxd → src/gevent/_gevent_c_semaphore.pxd

 cimport cython
 
-from gevent.__abstract_linkable cimport AbstractLinkable
+from gevent._gevent_c_abstract_linkable cimport AbstractLinkable
 cdef Timeout
 
 

src/gevent/__waiter.pxd → src/gevent/_gevent_c_waiter.pxd

 cimport cython
 
-from gevent.__greenlet_primitives cimport SwitchOutGreenletWithLoop
-from gevent.__hub_local cimport get_hub_noargs as get_hub
+from gevent._gevent_c_greenlet_primitives cimport SwitchOutGreenletWithLoop
+from gevent._gevent_c_hub_local cimport get_hub_noargs as get_hub
 
 cdef sys
 cdef ConcurrentObjectUseError

src/gevent/_event.pxd → src/gevent/_gevent_cevent.pxd

 cimport cython
 
-from gevent.__hub_local cimport get_hub_noargs as get_hub
-from gevent.__abstract_linkable cimport AbstractLinkable
+from gevent._gevent_c_hub_local cimport get_hub_noargs as get_hub
+from gevent._gevent_c_abstract_linkable cimport AbstractLinkable
 
 cdef _None
 cdef reraise

src/gevent/_greenlet.pxd → src/gevent/_gevent_cgreenlet.pxd

 # cython: auto_pickle=False
 
 cimport cython
-from gevent.__ident cimport IdentRegistry
-from gevent.__hub_local cimport get_hub_noargs as get_hub
-from gevent.__waiter cimport Waiter
-from gevent.__greenlet_primitives cimport SwitchOutGreenletWithLoop
+from gevent._gevent_c_ident cimport IdentRegistry
+from gevent._gevent_c_hub_local cimport get_hub_noargs as get_hub
+from gevent._gevent_c_waiter cimport Waiter
+from gevent._gevent_c_greenlet_primitives cimport SwitchOutGreenletWithLoop
 
 cdef bint _PYPY
 cdef sys_getframe

src/gevent/_local.pxd → src/gevent/_gevent_clocal.pxd

 # cython: auto_pickle=False
 
 cimport cython
-from gevent._greenlet cimport Greenlet
+from gevent._gevent_cgreenlet cimport Greenlet
 
 cdef bint _PYPY
 cdef ref

src/gevent/_queue.pxd → src/gevent/_gevent_cqueue.pxd

 cimport cython
-from gevent.__waiter cimport Waiter
-from gevent._event cimport Event
-from gevent.__hub_local cimport get_hub_noargs as get_hub
+from gevent._gevent_c_waiter cimport Waiter
+from gevent._gevent_cevent cimport Event
+from gevent._gevent_c_hub_local cimport get_hub_noargs as get_hub
 
 cdef bint _greenlet_imported
 cdef _heappush

src/gevent/_util.py

@@ -75,9 +75,19 @@ def copy_globals(source,
 
 def import_c_accel(globs, cname):
     """
-    Import the C-accelerator for the __name__
+    Import the C-accelerator for the *cname*
     and copy its globals.
+
+    The *cname* should be hardcoded to match the expected
+    C accelerator module.
+
+    Unless PURE_PYTHON is set (in the environment or automatically
+    on PyPy), then the C-accelerator is required.
     """
+    if not cname.startswith('gevent._gevent_c'):
+        # Old module code that hasn't been updated yet.
+        cname = cname.replace('gevent._',
+                              'gevent._gevent_c')
 
     name = globs.get('__name__')
 

src/gevent/libev/corecext.pyx

@@ -8,7 +8,7 @@
 # that's a new feature that we don't need or want to allow in a gevent
 # point release.
 
-# cython: emit_code_comments=False, auto_pickle=False
+# cython: emit_code_comments=False, auto_pickle=False, language_level=3str
 
 # NOTE: We generally cannot use the Cython IF directive as documented
 # at
@@ -19,6 +19,9 @@
 # C file for all platforms so that end users that don't use a binary
 # wheel don't have to sit through cythonpp and other steps the Makefile does.
 # See https://github.com/gevent/gevent/issues/1076
+# We compile in 3str mode, which should mean we get absolute import
+# by default.
+from __future__ import absolute_import
 
 cimport cython
 cimport libev
@@ -33,14 +36,11 @@ cdef extern from "Python.h":
     int    Py_ReprEnter(object)
     void   Py_ReprLeave(object)
 
-# Work around lack of absolute_import in Cython
-# Note for PY3: not doing so will leave reference to locals() on import
-# (reproducible under Python 3.3, not under Python 3.4; see test__refcount_core.py)
-sys = __import__('sys', level=0)
-os = __import__('os', level=0)
-traceback = __import__('traceback', level=0)
-signalmodule = __import__('signal', level=0)
-getswitchinterval = __import__('gevent', level=0).getswitchinterval
+import sys
+import os
+import traceback
+import signal as signalmodule
+from gevent import getswitchinterval
 
 
 __all__ = ['get_version',

src/gevent/tests/test___ident.py

@@ -71,7 +71,7 @@ class TestCExt(greentest.TestCase):
 
     def test_c_extension(self):
         self.assertEqual(IdentRegistry.__module__,
-                         'gevent.__ident')
+                         'gevent._gevent_c_ident')
 
 
 

src/gevent/tests/test__greenlet.py

@@ -828,9 +828,9 @@ class TestCExt(greentest.TestCase): # pragma: no cover (we only do coverage on p
 
     def test_c_extension(self):
         self.assertEqual(greenlet.Greenlet.__module__,
-                         'gevent._greenlet')
+                         'gevent._gevent_cgreenlet')
         self.assertEqual(greenlet.SpawnedLink.__module__,
-                         'gevent._greenlet')
+                         'gevent._gevent_cgreenlet')
 
 @greentest.skipWithCExtensions("Needs pure python")
 class TestPure(greentest.TestCase):

src/gevent/tests/test__local.py

@@ -414,7 +414,7 @@ class TestCExt(greentest.TestCase): # pragma: no cover
 
     def test_c_extension(self):
         self.assertEqual(local.__module__,
-                         'gevent._local')
+                         'gevent._gevent_clocal')
 
 @greentest.skipWithCExtensions("Needs pure-python")
 class TestPure(greentest.TestCase):

src/gevent/tests/test__semaphore.py

@@ -91,7 +91,7 @@ class TestCExt(greentest.TestCase):
 
     def test_c_extension(self):
         self.assertEqual(Semaphore.__module__,
-                         'gevent.__semaphore')
+                         'gevent._gevent_c_semaphore')
 
 
 class SwitchWithFixedHash(object):