Get non-embedded libuv working on POSIX at least.

Fixes #1395

.travis.yml

@@ -145,10 +145,14 @@ jobs:
         - rm -rf $BUILD_LIBS/share/man/
         - ls -l $BUILD_LIBS $BUILD_LIBS/lib $BUILD_LIBS/include
         - pip install --no-build-isolation .[test]
-        - objdump -p $G_SITE/gevent/libev/*so
+        # Test that we're actually linking
+        # to the .so file.
+        - objdump -p $G_SITE/gevent/libev/_corecffi*so | grep "NEEDED.*libev.so"
+        - objdump -p $G_SITE/gevent/libuv/_corecffi*so | grep "NEEDED.*libuv.so"
       script:
         # Verify that we got non-embedded builds
         - python -c 'import gevent.libev.corecffi as CF; assert not CF.LIBEV_EMBED'
+        - python -c 'import gevent.libuv.loop as CF; assert not CF.libuv.LIBUV_EMBED'
 
     # Ok, now we switch to the test stage. These are all in addition
     # to the jobs created by the matrix (and should override the `script` command).
@@ -244,17 +248,18 @@ jobs:
 
     # 2.7, no-embed. Run the tests that exercise the libraries we
     # linked to.
-    # XXX: The CFFI backends, as exercised by test-lib[eu]v-jobs
-    # don't really support this!
     - <<: *test-ares-jobs
+      # This job exercises both the non-embedded ares resolver
+      # and the non-embedded Cython libev loop.
       env: TRAVIS_PYTHON_VERSION=2.7 GEVENTSETUP_EMBED=0
       name: ares27-noembed
-    # - <<: *test-libuv-jobs
-    #   env: TRAVIS_PYTHON_VERSION=2.7 GEVENTSETUP_EMBED=0
-    #   name: libuv27-noembed
-    # - <<: *test-libev-jobs
-    #   env: TRAVIS_PYTHON_VERSION=2.7 GEVENTSETUP_EMBED=0
-    #   name: libev27-noembed
+    # These exercise the CFFI versions.
+    - <<: *test-libuv-jobs
+      env: TRAVIS_PYTHON_VERSION=2.7 GEVENTSETUP_EMBED=0
+      name: libuv27-noembed
+    - <<: *test-libev-jobs
+      env: TRAVIS_PYTHON_VERSION=2.7 GEVENTSETUP_EMBED=0
+      name: libev27-noembed
 
     # PyPy 2.7
     - <<: *test-dnspython-jobs

CHANGES.rst

@@ -90,6 +90,9 @@
   variables. Instead, use ``GEVENTSETUP_EMBED`` and
   ``GEVENTSETUP_EMBED_LIBEV``. See :issue:`1402`.
 
+- The CFFI backends now respect the embed build-time setting. This allows
+  building the libuv backend without embedding libuv (except on Windows).
+
 - Support test resources. This allows disabling tests that use the
   network. See :ref:`limiting-test-resource-usage` for more.
 

_setuplibev.py

@@ -22,7 +22,6 @@ from _setuputils import DEFINE_MACROS
 from _setuputils import glob_many
 from _setuputils import dep_abspath
 from _setuputils import should_embed
-from _setuputils import cythonize1
 
 
 LIBEV_EMBED = should_embed('libev')

_setuputils.py

@@ -87,7 +87,6 @@ def _bool_from_environ(key):
     raise ValueError('Environment variable %r has invalid value %r. '
                      'Please set it to 1, 0 or an empty string' % (key, value))
 
-IGNORE_CFFI = _bool_from_environ("GEVENTSETUP_NO_CFFI_BUILD")
 
 def _check_embed(key, defkey, path=None, warn=False):
     """

docs/installing_from_source.rst

@@ -107,11 +107,6 @@ yes/no.
   In general, setting ``CPPFLAGS`` is more general and can contain
   other macros recognized by libev.
 
-``GEVENTSETUP_NO_CFFI_BUILD``
-  A boolean; when set to true, this disables all attempts at building
-  the CFFI modules. *This disables libuv.* (TODO: verify that.)
-  Ignored on PyPy and ignored on Windows.
-
 
 Embedding Libraries
 -------------------
@@ -124,8 +119,7 @@ embedding, especially in the case of libev, can be more efficient as
 features not needed by gevent can be disabled, resulting in smaller or
 faster libraries or runtimes.
 
-However, this can be disabled (TODO: verify how this interacts with
-CFFI; see NO_CFFI_BUILD), either for all libraries at once or for
+However, this can be disabled, either for all libraries at once or for
 individual libraries.
 
 When embedding a library is disabled, the library must already be

setup.py

@@ -17,7 +17,6 @@ from _setuputils import read
 from _setuputils import read_version
 from _setuputils import system
 from _setuputils import PYPY, WIN
-from _setuputils import IGNORE_CFFI
 from _setuputils import ConfiguringBuildExt
 from _setuputils import GeventClean
 from _setuputils import BuildFailed
@@ -285,15 +284,6 @@ for mod in _to_cythonize:
 del _to_cythonize
 
 
-if IGNORE_CFFI and not PYPY and not WIN:
-    # Allow distributors to turn off CFFI builds
-    # even if it's available, because CFFI always embeds
-    # our copy of libev/libuv and they may not want that.
-    # Not allowed on PyPy and not allowed on Windows, because those
-    # backends are required there.
-    # TODO: CONFIRM if this is still the case.
-    del cffi_modules[:]
-
 ## Extras
 
 EXTRA_DNSPYTHON = [

src/gevent/libev/_corecffi_build.py

@@ -12,8 +12,12 @@ import os
 import os.path # pylint:disable=no-name-in-module
 from cffi import FFI
 
-# We must be run from the directory containing setup.py.
-import _setuplibev
+sys.path.append(".")
+try:
+    import _setuplibev
+except ImportError:
+    print("This file must be imported with setup.py in the current working dir.")
+    raise
 
 thisdir = os.path.dirname(os.path.abspath(__file__))
 setup_dir = os.path.abspath(os.path.join(thisdir, '..', '..', '..'))

src/gevent/libuv/_corecffi_build.py

@@ -11,16 +11,29 @@ import sys
 import os
 import os.path # pylint:disable=no-name-in-module
 
+from cffi import FFI
+
+sys.path.append(".")
+
+try:
+    import _setuputils
+except ImportError:
+    print("This file must be imported with setup.py in the current working dir.")
+    raise
+
 
 __all__ = []
 
 WIN = sys.platform.startswith('win32')
+LIBUV_EMBED = _setuputils.should_embed('libuv')
+print("Embedding libuv?", LIBUV_EMBED)
 
-
-from cffi import FFI
 ffi = FFI()
 
 thisdir = os.path.dirname(os.path.abspath(__file__))
+setup_py_dir = os.path.abspath(os.path.join(thisdir, '..', '..', '..'))
+libuv_dir = os.path.abspath(os.path.join(setup_py_dir, 'deps', 'libuv'))
+
 def read_source(name):
     with open(os.path.join(thisdir, name), 'r') as f:
         return f.read()
@@ -49,12 +62,9 @@ _void_pointer_as_integer = 'intptr_t'
 _cdef = _cdef.replace("GEVENT_UV_OS_SOCK_T", 'int' if not WIN else _void_pointer_as_integer)
 
 
-setup_py_dir = os.path.abspath(os.path.join(thisdir, '..', '..', '..'))
-libuv_dir = os.path.abspath(os.path.join(setup_py_dir, 'deps', 'libuv'))
 
 
 LIBUV_INCLUDE_DIRS = [
-    thisdir, # libev_vfd.h
     os.path.join(libuv_dir, 'include'),
     os.path.join(libuv_dir, 'src'),
 ]
@@ -192,7 +202,9 @@ elif sys.platform.startswith('sunos'):
     ]
 
 
-LIBUV_MACROS = []
+LIBUV_MACROS = [
+    ('LIBUV_EMBED', int(LIBUV_EMBED)),
+]
 
 def _define_macro(name, value):
     LIBUV_MACROS.append((name, value))
@@ -239,6 +251,11 @@ elif WIN:
     _add_library('userenv')
     _add_library('ws2_32')
 
+if not LIBUV_EMBED:
+    del LIBUV_SOURCES[:]
+    del LIBUV_INCLUDE_DIRS[:]
+    _add_library('uv')
+
 ffi.cdef(_cdef)
 ffi.set_source('gevent.libuv._corecffi',
                _source,
@@ -249,4 +266,9 @@ ffi.set_source('gevent.libuv._corecffi',
                define_macros=list(LIBUV_MACROS))
 
 if __name__ == '__main__':
-    ffi.compile()
+    # See notes in libev/_corecffi_build.py for how to test this.
+    #
+    # Other than the obvious directory changes, the changes are:
+    #
+    # CPPFLAGS=-Ideps/libuv/include/
+    ffi.compile(verbose=True)

src/gevent/libuv/_corecffi_cdef.c

+/* access whether we built embedded or not */
+
+#define LIBUV_EMBED ...
+
 /* markers for the CFFI parser. Replaced when the string is read. */
 #define GEVENT_STRUCT_DONE int
 #define GEVENT_ST_NLINK_T int