cffi: put compiled modules into mercurial.cffi package

Don't pollute the top-level namespace.

mercurial/cffi/bdiffbuild.py

@@ -4,7 +4,7 b' import cffi'
 import os
 
 ffi = cffi.FFI()
-ffi.set_source("_bdiff_cffi",
+ffi.set_source("mercurial.cffi._bdiff",
     open(os.path.join(os.path.join(os.path.dirname(__file__), '..'),
         'bdiff.c')).read(), include_dirs=['mercurial'])
 ffi.cdef("""

mercurial/cffi/mpatchbuild.py

@@ -6,7 +6,7 b' import os'
 ffi = cffi.FFI()
 mpatch_c = os.path.join(os.path.join(os.path.dirname(__file__), '..',
                                      'mpatch.c'))
-ffi.set_source("_mpatch_cffi", open(mpatch_c).read(),
+ffi.set_source("mercurial.cffi._mpatch", open(mpatch_c).read(),
                include_dirs=["mercurial"])
 ffi.cdef("""
 

mercurial/cffi/osutilbuild.py

@@ -3,7 +3,7 b' from __future__ import absolute_import'
 import cffi
 
 ffi = cffi.FFI()
-ffi.set_source("_osutil_cffi", """
+ffi.set_source("mercurial.cffi._osutil", """
 #include <sys/attr.h>
 #include <sys/vnode.h>
 #include <unistd.h>

mercurial/pure/bdiff.py

@@ -96,7 +96,7 b' def fixws(text, allws):'
 
 if modulepolicy not in policynocffi:
     try:
-        from _bdiff_cffi import ffi, lib
+        from ..cffi._bdiff import ffi, lib
     except ImportError:
         if modulepolicy == 'cffi': # strict cffi import
             raise

mercurial/pure/mpatch.py

@@ -130,7 +130,7 b' def patchedsize(orig, delta):'
 
 if modulepolicy not in policynocffi:
     try:
-        from _mpatch_cffi import ffi, lib
+        from ..cffi._mpatch import ffi, lib
     except ImportError:
         if modulepolicy == 'cffi': # strict cffi import
             raise

mercurial/pure/osutil.py

@@ -71,7 +71,7 b' def listdirpure(path, stat=False, skip=N'
 ffi = None
 if modulepolicy not in policynocffi and pycompat.sysplatform == 'darwin':
     try:
-        from _osutil_cffi import ffi, lib
+        from ..cffi._osutil import ffi, lib
     except ImportError:
         if modulepolicy == 'cffi': # strict cffi import
             raise

setup.py

@@ -582,6 +582,7 b" cmdclass = {'build': hgbuild,"
 
 packages = ['mercurial',
             'mercurial.cext',
+            'mercurial.cffi',
             'mercurial.hgweb',
             'mercurial.httpclient',
             'mercurial.pure',