Core mojo API for python.

Review URL: https://codereview.chromium.org/377293002

Cr-Commit-Position: refs/heads/master@{#291701}

17 files changed, 1746 insertions, 0 deletions

diff --git a/mojo/BUILD.gn b/mojo/BUILD.gn
index 4a46ecd..39b3859 100644
--- a/mojo/BUILD.gn
+++ b/mojo/BUILD.gn
@@ -13,6 +13,12 @@ group("mojo") {
     "//mojo/services",
     "//mojo/shell:mojo_shell",
   ]
+
+  if (is_linux) {
+    deps += [
+      "//mojo/python",
+    ]
+  }
 }
 
 group("tests") {
diff --git a/mojo/mojo.gyp b/mojo/mojo.gyp
index f38a793..acd8409 100644
--- a/mojo/mojo.gyp
+++ b/mojo/mojo.gyp
@@ -87,6 +87,13 @@
             'mojo_dbus_echo_service',
           ],
         }],
+        ['component != "shared_library" and OS == "linux"', {
+          'dependencies': [
+            'mojo_python_embedder',
+            'mojo_python_system',
+            'mojo_python',
+          ],
+        }],
       ]
     },
     {
@@ -531,5 +538,77 @@
         },
       ],
     }],
+    ['component!="shared_library" and OS=="linux"', {
+      'targets': [
+        {
+          'target_name': 'mojo_python_system',
+          'variables': {
+            'python_base_module': 'mojo',
+            'python_cython_module': 'system',
+          },
+          'sources': [
+            'public/python/mojo/c_core.pxd',
+            'public/python/mojo/system.pyx',
+          ],
+          'dependencies': [
+            'mojo_base.gyp:mojo_system',
+          ],
+          'includes': [ '../third_party/cython/cython_compiler.gypi' ],
+        },
+        {
+          'target_name': 'mojo_python_embedder',
+          'type': 'loadable_module',
+          'variables': {
+            'python_base_module': 'mojo',
+            'python_cython_module': 'embedder',
+          },
+          'sources': [
+            'python/system/mojo/embedder.pyx',
+          ],
+          'dependencies': [
+            'mojo_base.gyp:mojo_system_impl',
+          ],
+          'includes': [ '../third_party/cython/cython_compiler.gypi' ],
+        },
+        {
+          'target_name': 'mojo_python',
+          'type': 'none',
+          'variables': {
+            'python_base_module': 'mojo',
+          },
+          'sources': [
+            'public/python/mojo/__init__.py',
+          ],
+          'dependencies': [
+            'mojo_python_embedder',
+            'mojo_python_system',
+          ],
+          'includes': [ '../third_party/cython/python_module.gypi' ],
+        },
+        {
+          'target_name': 'mojo_python_unittests',
+          'type': 'none',
+          'actions': [
+            {
+              'action_name': 'run_mojo_python_unittests',
+              'inputs': [
+                'python/tests/test_core.py',
+                '<(SHARED_INTERMEDIATE_DIR)/mojo_python_py_module.stamp',
+                '<(PRODUCT_DIR)/python/mojo/__init__.py',
+              ],
+              'outputs': [
+                'none',
+              ],
+              'action': [
+                'python', '<@(_inputs)', '<(PRODUCT_DIR)/python',
+              ],
+            },
+          ],
+          'dependency': [
+            'mojo_python',
+          ],
+        },
+      ],
+    }],
   ],
 }
diff --git a/mojo/public/BUILD.gn b/mojo/public/BUILD.gn
index 631b6e9..03aefb9 100644
--- a/mojo/public/BUILD.gn
+++ b/mojo/public/BUILD.gn
@@ -14,6 +14,12 @@ group("public") {
     "//mojo/public/js/bindings",
   ]
 
+  if (is_linux) {
+    deps += [
+      "//mojo/public/python",
+    ]
+  }
+
   if (is_android) {
     deps += [
       "//mojo/public/java:system",
diff --git a/mojo/public/python/BUILD.gn b/mojo/public/python/BUILD.gn
new file mode 100644
index 0000000..c1c6fbc
--- /dev/null
+++ b/mojo/public/python/BUILD.gn
@@ -0,0 +1,33 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/cython/rules.gni")
+
+group("python") {
+  deps = [
+    ":base",
+    ":system",
+  ]
+}
+
+python_binary_module("system") {
+  python_base_module = "mojo"
+  sources = [
+    "mojo/c_core.pxd",
+    "mojo/system.pyx",
+  ]
+  deps = [
+    "//mojo/public/c/system",
+    ":base",
+  ]
+}
+
+copy("base") {
+  sources = [
+    "mojo/__init__.py",
+  ]
+  outputs = [
+    "$root_out_dir/python/mojo/__init__.py",
+  ]
+}
diff --git a/mojo/public/python/mojo/__init__.py b/mojo/public/python/mojo/__init__.py
new file mode 100644
index 0000000..4d6aabb
--- /dev/null
+++ b/mojo/public/python/mojo/__init__.py
@@ -0,0 +1,3 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
diff --git a/mojo/public/python/mojo/c_core.pxd b/mojo/public/python/mojo/c_core.pxd
new file mode 100644
index 0000000..80b8487d
--- /dev/null
+++ b/mojo/public/python/mojo/c_core.pxd
@@ -0,0 +1,201 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# distutils: language = c++
+
+from cpython.buffer cimport PyBUF_CONTIG
+from cpython.buffer cimport PyBUF_CONTIG_RO
+from cpython.buffer cimport Py_buffer
+from cpython.buffer cimport PyBuffer_FillInfo
+from cpython.buffer cimport PyBuffer_Release
+from cpython.buffer cimport PyObject_GetBuffer
+from cpython.mem cimport PyMem_Malloc, PyMem_Free
+from libc.stdint cimport int32_t, int64_t, uint32_t, uint64_t, uintptr_t
+
+cdef extern from "third_party/cython/python_export.h":
+  pass
+
+cdef extern from "mojo/public/platform/native/system_thunks.h" nogil:
+  cdef struct MojoSystemThunks:
+    pass
+
+cdef extern size_t MojoSetSystemThunks(const MojoSystemThunks* system_thunks)
+
+cdef extern from "mojo/public/c/system/core.h" nogil:
+  # types.h
+  ctypedef int64_t MojoTimeTicks
+
+  ctypedef uint32_t MojoHandle
+  const MojoHandle MOJO_HANDLE_INVALID
+
+  ctypedef int32_t MojoResult
+  const MojoResult MOJO_RESULT_OK
+  const MojoResult MOJO_RESULT_CANCELLED
+  const MojoResult MOJO_RESULT_UNKNOWN
+  const MojoResult MOJO_RESULT_INVALID_ARGUMENT
+  const MojoResult MOJO_RESULT_DEADLINE_EXCEEDED
+  const MojoResult MOJO_RESULT_NOT_FOUND
+  const MojoResult MOJO_RESULT_ALREADY_EXISTS
+  const MojoResult MOJO_RESULT_PERMISSION_DENIED
+  const MojoResult MOJO_RESULT_RESOURCE_EXHAUSTED
+  const MojoResult MOJO_RESULT_FAILED_PRECONDITION
+  const MojoResult MOJO_RESULT_ABORTED
+  const MojoResult MOJO_RESULT_OUT_OF_RANGE
+  const MojoResult MOJO_RESULT_UNIMPLEMENTED
+  const MojoResult MOJO_RESULT_INTERNAL
+  const MojoResult MOJO_RESULT_UNAVAILABLE
+  const MojoResult MOJO_RESULT_DATA_LOSS
+  const MojoResult MOJO_RESULT_BUSY
+  const MojoResult MOJO_RESULT_SHOULD_WAIT
+
+  ctypedef uint64_t MojoDeadline
+  const MojoDeadline MOJO_DEADLINE_INDEFINITE
+
+  ctypedef uint32_t MojoHandleSignals
+  const MojoHandleSignals MOJO_HANDLE_SIGNAL_NONE
+  const MojoHandleSignals MOJO_HANDLE_SIGNAL_READABLE
+  const MojoHandleSignals MOJO_HANDLE_SIGNAL_WRITABLE
+
+  # functions.h
+  MojoTimeTicks MojoGetTimeTicksNow()
+  MojoResult MojoClose(MojoHandle handle)
+  MojoResult MojoWait(MojoHandle handle,
+                      MojoHandleSignals signals,
+                      MojoDeadline deadline)
+  MojoResult MojoWaitMany(const MojoHandle* handles,
+                          const MojoHandleSignals* signals,
+                          uint32_t num_handles,
+                          MojoDeadline deadline)
+
+  # message_pipe.h
+  ctypedef uint32_t MojoCreateMessagePipeOptionsFlags
+  const MojoCreateMessagePipeOptionsFlags MOJO_CREATE_MESSAGE_PIPE_OPTIONS_FLAG_NONE
+
+  ctypedef uint32_t MojoWriteMessageFlags
+  const MojoWriteMessageFlags MOJO_WRITE_MESSAGE_FLAG_NONE
+
+  ctypedef uint32_t MojoReadMessageFlags
+  const MojoReadMessageFlags MOJO_READ_MESSAGE_FLAG_NONE
+  const MojoReadMessageFlags MOJO_READ_MESSAGE_FLAG_MAY_DISCARD
+
+  cdef struct MojoCreateMessagePipeOptions:
+    uint32_t struct_size
+    MojoCreateMessagePipeOptionsFlags flags
+
+  MojoResult MojoCreateMessagePipe(
+      const MojoCreateMessagePipeOptions* options,
+      MojoHandle* message_pipe_handle0,
+      MojoHandle* message_pipe_handle1)
+
+  MojoResult MojoWriteMessage(
+      MojoHandle message_pipe_handle,
+      const void* bytes,
+      uint32_t num_bytes,
+      const MojoHandle* handles,
+      uint32_t num_handles,
+      MojoWriteMessageFlags flags)
+
+  MojoResult MojoReadMessage(
+      MojoHandle message_pipe_handle,
+      void* bytes,
+      uint32_t* num_bytes,
+      MojoHandle* handles,
+      uint32_t* num_handles,
+      MojoReadMessageFlags flags)
+
+  # data_pipe.h
+  ctypedef uint32_t MojoCreateDataPipeOptionsFlags
+  const MojoCreateDataPipeOptionsFlags MOJO_CREATE_DATA_PIPE_OPTIONS_FLAG_NONE
+  const MojoCreateDataPipeOptionsFlags MOJO_CREATE_DATA_PIPE_OPTIONS_FLAG_MAY_DISCARD
+
+  cdef struct MojoCreateDataPipeOptions:
+    uint32_t struct_size
+    MojoCreateDataPipeOptionsFlags flags
+    uint32_t element_num_bytes
+    uint32_t capacity_num_bytes
+
+  ctypedef uint32_t MojoWriteDataFlags
+
+  const MojoWriteDataFlags MOJO_WRITE_DATA_FLAG_NONE
+  const MojoWriteDataFlags MOJO_WRITE_DATA_FLAG_ALL_OR_NONE
+
+  ctypedef uint32_t MojoReadDataFlags
+
+  const MojoReadDataFlags MOJO_READ_DATA_FLAG_NONE
+  const MojoReadDataFlags MOJO_READ_DATA_FLAG_ALL_OR_NONE
+  const MojoReadDataFlags MOJO_READ_DATA_FLAG_DISCARD
+  const MojoReadDataFlags MOJO_READ_DATA_FLAG_QUERY
+
+  MojoResult MojoCreateDataPipe(
+      const MojoCreateDataPipeOptions* options,
+      MojoHandle* data_pipe_producer_handle,
+      MojoHandle* data_pipe_consumer_handle)
+
+  MojoResult MojoWriteData(
+      MojoHandle data_pipe_producer_handle,
+      const void* elements,
+      uint32_t* num_bytes,
+      MojoWriteDataFlags flags)
+
+  MojoResult MojoBeginWriteData(
+      MojoHandle data_pipe_producer_handle,
+      void** buffer,
+      uint32_t* buffer_num_bytes,
+      MojoWriteDataFlags flags)
+
+  MojoResult MojoEndWriteData(
+      MojoHandle data_pipe_producer_handle,
+      uint32_t num_bytes_written)
+
+  MojoResult MojoReadData(
+      MojoHandle data_pipe_consumer_handle,
+      void* elements,
+      uint32_t* num_bytes,
+      MojoReadDataFlags flags)
+
+  MojoResult MojoBeginReadData(
+      MojoHandle data_pipe_consumer_handle,
+      const void** buffer,
+      uint32_t* buffer_num_bytes,
+      MojoReadDataFlags flags)
+
+  MojoResult MojoEndReadData(
+      MojoHandle data_pipe_consumer_handle,
+      uint32_t num_bytes_read)
+
+  # buffer.h
+  ctypedef uint32_t MojoCreateSharedBufferOptionsFlags
+  const MojoCreateSharedBufferOptionsFlags MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE
+
+  cdef struct MojoCreateSharedBufferOptions:
+    uint32_t struct_size
+    MojoCreateSharedBufferOptionsFlags flags
+
+  ctypedef uint32_t MojoDuplicateBufferHandleOptionsFlags
+  const MojoDuplicateBufferHandleOptionsFlags MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE
+
+  cdef struct MojoDuplicateBufferHandleOptions:
+    uint32_t struct_size
+    MojoDuplicateBufferHandleOptionsFlags flags
+
+  ctypedef uint32_t MojoMapBufferFlags
+  const MojoMapBufferFlags MOJO_MAP_BUFFER_FLAG_NONE
+
+  MojoResult MojoCreateSharedBuffer(
+      const MojoCreateSharedBufferOptions* options,
+      uint64_t num_bytes,
+      MojoHandle* shared_buffer_handle)
+
+  MojoResult MojoDuplicateBufferHandle(
+      MojoHandle buffer_handle,
+      const MojoDuplicateBufferHandleOptions* options,
+      MojoHandle* new_buffer_handle)
+
+  MojoResult MojoMapBuffer(MojoHandle buffer_handle,
+                           uint64_t offset,
+                           uint64_t num_bytes,
+                           void** buffer,
+                           MojoMapBufferFlags flags)
+
+  MojoResult MojoUnmapBuffer(void* buffer)
diff --git a/mojo/public/python/mojo/system.pyx b/mojo/public/python/mojo/system.pyx
new file mode 100644
index 0000000..80b8dd3
--- /dev/null
+++ b/mojo/public/python/mojo/system.pyx
@@ -0,0 +1,696 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# distutils language = c++
+
+cimport c_core
+
+from cpython.buffer cimport PyBUF_CONTIG
+from cpython.buffer cimport PyBUF_CONTIG_RO
+from cpython.buffer cimport Py_buffer
+from cpython.buffer cimport PyBuffer_FillInfo
+from cpython.buffer cimport PyBuffer_Release
+from cpython.buffer cimport PyObject_GetBuffer
+from cpython.mem cimport PyMem_Malloc, PyMem_Free
+from libc.stdint cimport int32_t, int64_t, uint32_t, uint64_t, uintptr_t
+
+def set_system_thunks(system_thunks_as_object):
+  """Bind the basic Mojo Core functions.
+
+  This should only be used by the embedder.
+  """
+  cdef const c_core.MojoSystemThunks* system_thunks = (
+      <const c_core.MojoSystemThunks*><uintptr_t>system_thunks_as_object)
+  c_core.MojoSetSystemThunks(system_thunks)
+
+HANDLE_INVALID = c_core.MOJO_HANDLE_INVALID
+RESULT_OK = c_core.MOJO_RESULT_OK
+RESULT_CANCELLED = c_core.MOJO_RESULT_CANCELLED
+RESULT_UNKNOWN = c_core.MOJO_RESULT_UNKNOWN
+RESULT_INVALID_ARGUMENT = c_core.MOJO_RESULT_INVALID_ARGUMENT
+RESULT_DEADLINE_EXCEEDED = c_core.MOJO_RESULT_DEADLINE_EXCEEDED
+RESULT_NOT_FOUND = c_core.MOJO_RESULT_NOT_FOUND
+RESULT_ALREADY_EXISTS = c_core.MOJO_RESULT_ALREADY_EXISTS
+RESULT_PERMISSION_DENIED = c_core.MOJO_RESULT_PERMISSION_DENIED
+RESULT_RESOURCE_EXHAUSTED = c_core.MOJO_RESULT_RESOURCE_EXHAUSTED
+RESULT_FAILED_PRECONDITION = c_core.MOJO_RESULT_FAILED_PRECONDITION
+RESULT_ABORTED = c_core.MOJO_RESULT_ABORTED
+RESULT_OUT_OF_RANGE = c_core.MOJO_RESULT_OUT_OF_RANGE
+RESULT_UNIMPLEMENTED = c_core.MOJO_RESULT_UNIMPLEMENTED
+RESULT_INTERNAL = c_core.MOJO_RESULT_INTERNAL
+RESULT_UNAVAILABLE = c_core.MOJO_RESULT_UNAVAILABLE
+RESULT_DATA_LOSS = c_core.MOJO_RESULT_DATA_LOSS
+RESULT_BUSY = c_core.MOJO_RESULT_BUSY
+RESULT_SHOULD_WAIT = c_core.MOJO_RESULT_SHOULD_WAIT
+DEADLINE_INDEFINITE = c_core.MOJO_DEADLINE_INDEFINITE
+HANDLE_SIGNAL_NONE = c_core.MOJO_HANDLE_SIGNAL_NONE
+HANDLE_SIGNAL_READABLE = c_core.MOJO_HANDLE_SIGNAL_READABLE
+HANDLE_SIGNAL_WRITABLE = c_core.MOJO_HANDLE_SIGNAL_WRITABLE
+WRITE_MESSAGE_FLAG_NONE = c_core.MOJO_WRITE_MESSAGE_FLAG_NONE
+READ_MESSAGE_FLAG_NONE = c_core.MOJO_READ_MESSAGE_FLAG_NONE
+READ_MESSAGE_FLAG_MAY_DISCARD = c_core.MOJO_READ_MESSAGE_FLAG_MAY_DISCARD
+WRITE_DATA_FLAG_NONE = c_core.MOJO_WRITE_DATA_FLAG_NONE
+WRITE_DATA_FLAG_ALL_OR_NONE = c_core.MOJO_WRITE_DATA_FLAG_ALL_OR_NONE
+READ_DATA_FLAG_NONE = c_core.MOJO_READ_DATA_FLAG_NONE
+READ_DATA_FLAG_ALL_OR_NONE = c_core.MOJO_READ_DATA_FLAG_ALL_OR_NONE
+READ_DATA_FLAG_DISCARD = c_core.MOJO_READ_DATA_FLAG_DISCARD
+READ_DATA_FLAG_QUERY = c_core.MOJO_READ_DATA_FLAG_QUERY
+MAP_BUFFER_FLAG_NONE = c_core.MOJO_MAP_BUFFER_FLAG_NONE
+
+def get_time_ticks_now():
+  """Monotonically increasing tick count representing "right now."
+
+  See mojo/public/c/system/functions.h
+  """
+  return c_core.MojoGetTimeTicksNow()
+
+cdef class _ScopedMemory:
+  """Allocate memory at creation, and deallocate it at destruction."""
+  cdef void* memory
+  def __init__(self, size):
+    self.memory = PyMem_Malloc(size)
+
+  def __dealloc__(self):
+    PyMem_Free(self.memory)
+
+cdef class _ScopedBuffer:
+  """Retrieve pointer to a buffer a creation, and release it at destruction.
+  """
+  cdef Py_buffer _buf
+  cdef void* buf
+  cdef Py_ssize_t len
+
+  def __init__(self, obj, flags=PyBUF_CONTIG_RO):
+    if obj:
+      if PyObject_GetBuffer(obj, &self._buf, flags) < 0:
+        raise TypeError('Unable to read buffer.')
+      self.buf = self._buf.buf
+      self.len = self._buf.len
+    else:
+      self.buf = NULL
+      self.len = 0
+
+  def __dealloc__(self):
+    if self.buf:
+      PyBuffer_Release(&self._buf)
+
+def _slice_buffer(buffer, size):
+  """Slice the given buffer, reducing it to the given size.
+
+  Return None if None is passed in.
+  """
+  if not buffer:
+    return buffer
+  return buffer[:size]
+
+cdef class _NativeMemoryView(object):
+  """Create a python buffer wrapping the given memory.
+
+  Will also retain the given handle until this object is deallocated.
+  """
+  cdef void* _memory
+  cdef uint32_t _size
+  cdef char _read_only
+  cdef char _wrapped
+  cdef object _handle
+
+  def __init__(self, handle):
+    self._handle = handle
+
+  def __cinit__(self):
+    self._memory = NULL
+    self._size = 0
+    self._read_only = True
+    self._wrapped = False
+
+  cdef wrap(self,
+            const void* memory,
+            uint32_t size,
+            read_only=True):
+    """Makes this buffer wraps the given memory.
+
+    Must be called before using this buffer, and must only be called once.
+    """
+    assert not self._wrapped
+    self._wrapped = True
+    self._memory = <void*>memory
+    self._size = size
+    self._read_only = read_only
+
+  # buffer interface (PEP 3118)
+  def __getbuffer__(self, Py_buffer *view, int flags):
+    assert self._wrapped
+    if view == NULL:
+      return
+    PyBuffer_FillInfo(view,
+                      self,
+                      self._memory,
+                      self._size,
+                      self._read_only,
+                      flags)
+
+  def __releasebuffer__(self, Py_buffer *view):
+    assert self._wrapped
+    pass
+
+  # legacy buffer interface
+  def __getsegcount__(self, Py_ssize_t *sizes):
+    assert self._wrapped
+    if sizes != NULL:
+      sizes[0] = self._size
+    return 1
+
+  def __getreadbuffer__(self, Py_ssize_t index, void **data):
+    assert self._wrapped
+    if index != 0:
+      raise SystemError('Index out of bounds: %d' % index)
+    data[0] = self._memory
+    return self._size
+
+  def __getwritebuffer__(self, Py_ssize_t index, void **data):
+    assert self._wrapped
+    if index != 0:
+      raise SystemError('Index out of bounds: %d' % index)
+    if self._read_only:
+      raise TypeError('Buffer is read-only.')
+    data[0] = self._memory
+    return self._size
+
+class MojoException(Exception):
+  """Exception wrapping a mojo result error code."""
+
+  def __init__(self, mojo_result):
+    self.mojo_result = mojo_result
+
+def wait_many(handles_and_signals, deadline):
+  """Waits on a list of handles.
+
+  Args:
+    handles_and_signals: list of tuples of handle and signal.
+
+  See mojo/public/c/system/functions.h
+  """
+  cdef uint32_t length = len(handles_and_signals)
+  cdef _ScopedMemory handles_alloc = _ScopedMemory(
+      sizeof(c_core.MojoHandle) * length)
+  cdef _ScopedMemory signals_alloc = _ScopedMemory(
+      sizeof(c_core.MojoHandleSignals) * length)
+  cdef c_core.MojoHandle* handles = <c_core.MojoHandle*>handles_alloc.memory
+  cdef c_core.MojoHandleSignals* signals = (
+      <c_core.MojoHandleSignals*>signals_alloc.memory)
+  cdef int index = 0
+  for (h, s) in handles_and_signals:
+    handles[index] = (<Handle?>h)._mojo_handle
+    signals[index] = s
+    index += 1
+  cdef c_core.MojoResult result = c_core.MOJO_RESULT_OK
+  cdef c_core.MojoDeadline cdeadline = deadline
+  with nogil:
+    result = c_core.MojoWaitMany(handles, signals, length, cdeadline)
+  return result
+
+cdef class DataPipeTwoPhaseBuffer(object):
+  """Return value for two phases read and write.
+
+  The buffer field contains the python buffer where data can be read or written.
+  When done with the buffer, the |end| method must be called with the number of
+  bytes read or written.
+  """
+
+  cdef object _buffer
+  cdef Handle _handle
+  cdef char _read
+
+  def __init__(self, handle, buffer, read=True):
+    self._buffer = buffer
+    self._handle = handle
+    self._read = read
+
+  def end(self, num_bytes):
+    self._buffer = None
+    cdef c_core.MojoResult result
+    if self._read:
+      result = c_core.MojoEndReadData(self._handle._mojo_handle, num_bytes)
+    else:
+      result = c_core.MojoEndWriteData(self._handle._mojo_handle, num_bytes)
+    self._handle = None
+    return result
+
+  @property
+  def buffer(self):
+    return self._buffer
+
+  def __dealloc__(self):
+    assert not self._buffer
+
+cdef class MappedBuffer(object):
+  """Return value for the |map| operation on shared buffer handles.
+
+  The buffer field contains the python buffer where data can be read or written.
+  When done with the buffer, the |unmap| method must be called.
+  """
+
+  cdef object _buffer
+  cdef object _handle
+  cdef object _cleanup
+
+  def __init__(self, handle, buffer, cleanup):
+    self._buffer = buffer
+    self._handle = handle
+    self._cleanup = cleanup
+
+  def unmap(self):
+    self._buffer = None
+    cdef c_core.MojoResult result = self._cleanup()
+    self._cleanup = None
+    self._handle = None
+    return result
+
+  @property
+  def buffer(self):
+    return self._buffer
+
+  def __dealloc__(self):
+    if self._buffer:
+      self.unmap()
+
+cdef class Handle(object):
+  """A mojo object."""
+
+  cdef c_core.MojoHandle _mojo_handle
+
+  def __init__(self, mojo_handle=c_core.MOJO_HANDLE_INVALID):
+    self._mojo_handle = mojo_handle
+
+  def _invalidate(self):
+    """Invalidate the current handle.
+
+    The close operation is not called. It is the responsability of the caller to
+    ensure that the handle is not leaked.
+    """
+    self._mojo_handle = c_core.MOJO_HANDLE_INVALID
+
+  def is_valid(self):
+    """Returns whether this handle is valid."""
+    return self._mojo_handle != c_core.MOJO_HANDLE_INVALID
+
+  def close(self):
+    """Closes this handle.
+
+    See mojo/public/c/system/functions.h
+    """
+    cdef c_core.MojoResult result = c_core.MOJO_RESULT_OK
+    if self.is_valid():
+      result = c_core.MojoClose(self._mojo_handle)
+      self._invalidate()
+    return result
+
+  def __dealloc__(self):
+    self.close()
+
+  def wait(self, signals, deadline):
+    """Waits on the given handle.
+
+    See mojo/public/c/system/functions.h
+    """
+    cdef c_core.MojoHandle handle = self._mojo_handle
+    cdef c_core.MojoHandleSignals csignals = signals
+    cdef c_core.MojoDeadline cdeadline = deadline
+    cdef c_core.MojoResult result
+    with nogil:
+      result = c_core.MojoWait(handle, csignals, cdeadline)
+    return result
+
+  def write_message(self,
+                    buffer=None,
+                    handles=None,
+                    flags=WRITE_MESSAGE_FLAG_NONE):
+    """Writes a message to the message pipe.
+
+    This method can only be used on a handle obtained from |MessagePipe()|.
+
+    See mojo/public/c/system/message_pipe.h
+    """
+    cdef _ScopedBuffer buffer_as_buffer = _ScopedBuffer(buffer)
+    cdef uint32_t input_buffer_length = buffer_as_buffer.len
+    cdef c_core.MojoHandle* input_handles = NULL
+    cdef uint32_t input_handles_length = 0
+    cdef _ScopedMemory handles_alloc = None
+    if handles:
+      input_handles_length = len(handles)
+      handles_alloc = _ScopedMemory(sizeof(c_core.MojoHandle) *
+                                    input_handles_length)
+      input_handles = <c_core.MojoHandle*>handles_alloc.memory
+      for i in xrange(input_handles_length):
+        input_handles[i] = (<Handle?>handles[i])._mojo_handle
+    cdef c_core.MojoResult res = c_core.MojoWriteMessage(self._mojo_handle,
+                                                         buffer_as_buffer.buf,
+                                                         input_buffer_length,
+                                                         input_handles,
+                                                         input_handles_length,
+                                                         flags)
+    if res == c_core.MOJO_RESULT_OK and handles:
+      # Handles have been transferred. Let's invalidate those.
+      for handle in handles:
+        handle._invalidate()
+    return res
+
+  def read_message(self,
+                   buffer=None,
+                   max_number_of_handles=0,
+                   flags=READ_MESSAGE_FLAG_NONE):
+    """Reads a message from the message pipe.
+
+    This method can only be used on a handle obtained from |MessagePipe()|.
+
+    This method returns a triplet of value (code, data, sizes):
+    - if code is RESULT_OK, sizes will be None, and data will be a pair of
+      (buffer, handles) where buffer is a view of the input buffer with the read
+      data, and handles is a list of received handles.
+    - if code is RESULT_RESOURCE_EXHAUSTED, data will be None and sizes will be
+      a pair of (buffer_size, handles_size) where buffer_size is the size of the
+      next message data and handles_size is the number of handles in the next
+      message.
+    - if code is any other value, data and sizes will be None.
+
+    See mojo/public/c/system/message_pipe.h
+    """
+    cdef _ScopedBuffer buffer_as_buffer = _ScopedBuffer(buffer, PyBUF_CONTIG)
+    cdef uint32_t input_buffer_length = buffer_as_buffer.len
+    cdef c_core.MojoHandle* input_handles = NULL
+    cdef uint32_t input_handles_length = 0
+    cdef _ScopedMemory handles_alloc = None
+    if max_number_of_handles > 0:
+      input_handles_length = max_number_of_handles
+      handles_alloc = _ScopedMemory(sizeof(c_core.MojoHandle) *
+                                    input_handles_length)
+      input_handles = <c_core.MojoHandle*>handles_alloc.memory
+    cdef res = c_core.MojoReadMessage(self._mojo_handle,
+                                      buffer_as_buffer.buf,
+                                      &input_buffer_length,
+                                      input_handles,
+                                      &input_handles_length,
+                                      flags)
+    if res == c_core.MOJO_RESULT_RESOURCE_EXHAUSTED:
+      return (res, None, (input_buffer_length, input_handles_length))
+    if res == c_core.MOJO_RESULT_OK:
+      returned_handles = [Handle(input_handles[i])
+                          for i in xrange(input_handles_length)]
+      return (res,
+              (_slice_buffer(buffer, input_buffer_length), returned_handles),
+              None)
+    return (res, None, None)
+
+  def write_data(self, buffer=None, flags=WRITE_DATA_FLAG_NONE):
+    """
+    Writes the given data to the data pipe producer.
+
+    This method can only be used on a producer handle obtained from
+    |DataPipe()|.
+
+    This method returns a tuple (code, num_bytes).
+    - If code is RESULT_OK, num_bytes is the number of written bytes.
+    - Otherwise, num_bytes is None.
+
+    See mojo/public/c/system/data_pipe.h
+    """
+    cdef _ScopedBuffer buffer_as_buffer = _ScopedBuffer(buffer)
+    cdef uint32_t input_buffer_length = buffer_as_buffer.len
+    cdef c_core.MojoResult res = c_core.MojoWriteData(self._mojo_handle,
+                                                      buffer_as_buffer.buf,
+                                                      &input_buffer_length,
+                                                      flags)
+    if res == c_core.MOJO_RESULT_OK:
+      return (res, input_buffer_length)
+    return (res, None)
+
+  def begin_write_data(self,
+                       min_size=None,
+                       flags=WRITE_DATA_FLAG_NONE):
+    """
+    Begins a two-phase write to the data pipe producer.
+
+    This method can only be used on a producer handle obtained from
+    |DataPipe()|.
+
+    This method returns a tuple (code, two_phase_buffer).
+    - If code is RESULT_OK, two_phase_buffer is a writable
+      DataPipeTwoPhaseBuffer
+    - Otherwise, two_phase_buffer is None.
+
+    See mojo/public/c/system/data_pipe.h
+    """
+    cdef void* out_buffer
+    cdef uint32_t out_size = 0
+    if min_size:
+      flags |= c_core.MOJO_WRITE_DATA_FLAG_ALL_OR_NONE
+      out_size = min_size
+    cdef c_core.MojoResult res = c_core.MojoBeginWriteData(self._mojo_handle,
+                                                           &out_buffer,
+                                                           &out_size,
+                                                           flags)
+    if res != c_core.MOJO_RESULT_OK:
+      return (res, None)
+    cdef _NativeMemoryView view_buffer = _NativeMemoryView(self)
+    view_buffer.wrap(out_buffer, out_size, read_only=False)
+    return (res, DataPipeTwoPhaseBuffer(self, memoryview(view_buffer), False))
+
+  def read_data(self, buffer=None, flags=READ_DATA_FLAG_NONE):
+    """Reads data from the data pipe consumer.
+
+    This method can only be used on a consumer handle obtained from
+    |DataPipe()|.
+
+    This method returns a tuple (code, buffer)
+    - if code is RESULT_OK, buffer will be a view of the input buffer with the
+      read data.
+    - otherwise, buffer will be None.
+
+    See mojo/public/c/system/data_pipe.h
+    """
+    cdef _ScopedBuffer buffer_as_buffer = _ScopedBuffer(buffer)
+    cdef uint32_t input_buffer_length = buffer_as_buffer.len
+    cdef c_core.MojoResult res = c_core.MojoReadData(self._mojo_handle,
+                                                     buffer_as_buffer.buf,
+                                                     &input_buffer_length,
+                                                     flags)
+    if res == c_core.MOJO_RESULT_OK:
+      return (res, _slice_buffer(buffer, input_buffer_length))
+    return (res, None)
+
+  def query_data(self, flags=READ_DATA_FLAG_NONE):
+    """Queries the amount of data available on the data pipe consumer.
+
+    This method can only be used on a consumer handle obtained from
+    |DataPipe()|.
+
+    This method returns a tuple (code, num_bytes)
+    - if code is RESULT_OK, num_bytes will be the number of bytes available on
+      the data pipe consumer.
+    - otherwise, num_bytes will be None.
+
+    See mojo/public/c/system/data_pipe.h
+    """
+    cdef uint32_t num_bytes = 0
+    cdef c_core.MojoResult res = c_core.MojoReadData(
+        self._mojo_handle,
+        NULL,
+        &num_bytes,
+        flags|c_core.MOJO_READ_DATA_FLAG_QUERY)
+    return (res, num_bytes)
+
+  def begin_read_data(self, min_size=None, flags=READ_DATA_FLAG_NONE):
+    """
+    Begins a two-phase read to the data pipe consumer.
+
+    This method can only be used on a consumer handle obtained from
+    |DataPipe()|.
+
+    This method returns a tuple (code, two_phase_buffer).
+    - If code is RESULT_OK, two_phase_buffer is a readable
+      DataPipeTwoPhaseBuffer
+    - Otherwise, two_phase_buffer is None.
+
+    See mojo/public/c/system/data_pipe.h
+    """
+    cdef const void* out_buffer
+    cdef uint32_t out_size = 0
+    if min_size:
+      flags |= c_core.MOJO_READ_DATA_FLAG_ALL_OR_NONE
+      out_size = min_size
+    cdef c_core.MojoResult res = c_core.MojoBeginReadData(self._mojo_handle,
+                                                          &out_buffer,
+                                                          &out_size,
+                                                          flags)
+    if res != c_core.MOJO_RESULT_OK:
+      return (res, None)
+    cdef _NativeMemoryView view_buffer = _NativeMemoryView(self)
+    view_buffer.wrap(out_buffer, out_size, read_only=True)
+    return (res, DataPipeTwoPhaseBuffer(self, memoryview(view_buffer), True))
+
+  def duplicate(self, options=None):
+    """Duplicate the shared buffer handle.
+
+    This method can only be used on a handle obtained from
+    |create_shared_buffer()| or |duplicate()|.
+
+    See mojo/public/c/system/buffer.h
+    """
+    cdef c_core.MojoDuplicateBufferHandleOptions coptions
+    cdef c_core.MojoDuplicateBufferHandleOptions* coptions_ptr = NULL
+    cdef c_core.MojoHandle cnew_handle = c_core.MOJO_HANDLE_INVALID
+    if options:
+      coptions.struct_size = sizeof(c_core.MojoDuplicateBufferHandleOptions)
+      coptions.flags = options.flags
+      coptions_ptr = &coptions
+    cdef c_core.MojoResult result = c_core.MojoDuplicateBufferHandle(
+        self._mojo_handle, coptions_ptr, &cnew_handle)
+    new_handle = Handle(cnew_handle)
+    if result != c_core.MOJO_RESULT_OK:
+      raise MojoException(result)
+    return new_handle
+
+  def map(self, offset, num_bytes, flags=MAP_BUFFER_FLAG_NONE):
+    """Maps the part (at offset |offset| of length |num_bytes|) of the buffer.
+
+    This method can only be used on a handle obtained from
+    |create_shared_buffer()| or |duplicate()|.
+
+    This method returns a tuple (code, mapped_buffer).
+    - If code is RESULT_OK, mapped_buffer is a readable/writable
+      MappedBuffer
+    - Otherwise, mapped_buffer is None.
+
+    See mojo/public/c/system/buffer.h
+    """
+    cdef void* buffer
+    res = c_core.MojoMapBuffer(self._mojo_handle,
+                               offset,
+                               num_bytes,
+                               &buffer,
+                               flags)
+    if res != c_core.MOJO_RESULT_OK:
+      return (res, None)
+    cdef _NativeMemoryView view_buffer = _NativeMemoryView(self)
+    view_buffer.wrap(buffer, num_bytes, read_only=False)
+    return (res, MappedBuffer(self,
+                              memoryview(view_buffer),
+                              lambda: c_core.MojoUnmapBuffer(buffer)))
+
+class CreateMessagePipeOptions(object):
+  """Options for creating a message pipe.
+
+  See mojo/public/c/system/message_pipe.h
+  """
+  FLAG_NONE = c_core.MOJO_CREATE_MESSAGE_PIPE_OPTIONS_FLAG_NONE
+
+  def __init__(self):
+    self.flags = CreateMessagePipeOptions.FLAG_NONE
+
+class MessagePipe(object):
+  """Creates a message pipe.
+
+  The two ends of the message pipe are accessible with the members handle0 and
+  handle1.
+
+  See mojo/public/c/system/message_pipe.h
+  """
+  def __init__(self, options=None):
+    cdef c_core.MojoCreateMessagePipeOptions coptions
+    cdef c_core.MojoCreateMessagePipeOptions* coptions_ptr = NULL
+    cdef c_core.MojoHandle chandle0 = c_core.MOJO_HANDLE_INVALID
+    cdef c_core.MojoHandle chandle1 = c_core.MOJO_HANDLE_INVALID
+    if options:
+      coptions.struct_size = sizeof(c_core.MojoCreateMessagePipeOptions)
+      coptions.flags = options.flags
+      coptions_ptr = &coptions
+    cdef c_core.MojoResult result = c_core.MojoCreateMessagePipe(coptions_ptr,
+                                                                 &chandle0,
+                                                                 &chandle1)
+    self.handle0 = Handle(chandle0)
+    self.handle1 = Handle(chandle1)
+    if result != c_core.MOJO_RESULT_OK:
+      raise c_core.MojoException(result)
+
+
+class CreateDataPipeOptions(object):
+  """Options for creating a data pipe.
+
+  See mojo/public/c/system/data_pipe.h
+  """
+  FLAG_NONE = c_core.MOJO_CREATE_DATA_PIPE_OPTIONS_FLAG_NONE
+  FLAG_MAY_DISCARD = c_core.MOJO_CREATE_DATA_PIPE_OPTIONS_FLAG_MAY_DISCARD
+
+  def __init__(self):
+    self.flags = CreateDataPipeOptions.FLAG_NONE
+    self.element_num_bytes = 1
+    self.capacity_num_bytes = 0
+
+class DataPipe(object):
+  """Creates a data pipe.
+
+  The producer end of the data pipe is accessible with the member
+  producer_handle and the consumer end of the data pipe is accessible with the
+  member cconsumer_handle.
+
+  See mojo/public/c/system/data_pipe.h
+  """
+  def __init__(self, options=None):
+    cdef c_core.MojoCreateDataPipeOptions coptions
+    cdef c_core.MojoCreateDataPipeOptions* coptions_ptr = NULL
+    cdef c_core.MojoHandle cproducer_handle = c_core.MOJO_HANDLE_INVALID
+    cdef c_core.MojoHandle cconsumer_handle = c_core.MOJO_HANDLE_INVALID
+    if options:
+      coptions.struct_size = sizeof(c_core.MojoCreateDataPipeOptions)
+      coptions.flags = options.flags
+      coptions.element_num_bytes = options.element_num_bytes
+      coptions.capacity_num_bytes = options.capacity_num_bytes
+      coptions_ptr = &coptions
+    cdef c_core.MojoResult result = c_core.MojoCreateDataPipe(coptions_ptr,
+                                                              &cproducer_handle,
+                                                              &cconsumer_handle)
+    self.producer_handle = Handle(cproducer_handle)
+    self.consumer_handle = Handle(cconsumer_handle)
+    if result != c_core.MOJO_RESULT_OK:
+      raise MojoException(result)
+
+class CreateSharedBufferOptions(object):
+  """Options for creating a shared buffer.
+
+  See mojo/public/c/system/buffer.h
+  """
+  FLAG_NONE = c_core.MOJO_CREATE_SHARED_BUFFER_OPTIONS_FLAG_NONE
+
+  def __init__(self):
+    self.flags = CreateSharedBufferOptions.FLAG_NONE
+
+def create_shared_buffer(num_bytes, options=None):
+  """Creates a buffer of size |num_bytes| bytes that can be shared.
+
+  See mojo/public/c/system/buffer.h
+  """
+  cdef c_core.MojoCreateSharedBufferOptions coptions
+  cdef c_core.MojoCreateSharedBufferOptions* coptions_ptr = NULL
+  cdef c_core.MojoHandle chandle = c_core.MOJO_HANDLE_INVALID
+  if options:
+    coptions.struct_size = sizeof(c_core.MojoCreateSharedBufferOptions)
+    coptions.flags = options.flags
+    coptions_ptr = &coptions
+  cdef c_core.MojoResult result = c_core.MojoCreateSharedBuffer(coptions_ptr,
+                                                                num_bytes,
+                                                                &chandle)
+  handle = Handle(chandle)
+  if result != c_core.MOJO_RESULT_OK:
+    raise MojoException(result)
+  return handle
+
+class DuplicateSharedBufferOptions(object):
+  """Options for duplicating a shared buffer.
+
+  See mojo/public/c/system/buffer.h
+  """
+  FLAG_NONE = c_core.MOJO_DUPLICATE_BUFFER_HANDLE_OPTIONS_FLAG_NONE
+
+  def __init__(self):
+    self.flags = DuplicateSharedBufferOptions.FLAG_NONE
diff --git a/mojo/python/BUILD.gn b/mojo/python/BUILD.gn
new file mode 100644
index 0000000..18b8737
--- /dev/null
+++ b/mojo/python/BUILD.gn
@@ -0,0 +1,29 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/cython/rules.gni")
+
+group("python") {
+  deps = [
+    ":embedder",
+  ]
+}
+
+group("tests") {
+  deps = [
+    "//mojo/python/tests",
+  ]
+}
+python_binary_module("embedder") {
+  python_base_module = "mojo"
+  sources = [
+    "system/mojo/embedder.pyx",
+  ]
+  deps = [
+    "//mojo/system",
+  ]
+  datadeps = [
+    "//mojo/public/python:system",
+  ]
+}
diff --git a/mojo/python/system/mojo/embedder.pyx b/mojo/python/system/mojo/embedder.pyx
new file mode 100644
index 0000000..c7021f0
--- /dev/null
+++ b/mojo/python/system/mojo/embedder.pyx
@@ -0,0 +1,41 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# distutils: language = c++
+
+from libc.stdint cimport uintptr_t
+
+from mojo import system
+
+cdef extern from "third_party/cython/python_export.h":
+  pass
+
+cdef extern from "base/memory/scoped_ptr.h":
+  cdef cppclass scoped_ptr[T]:
+    scoped_ptr(T*)
+
+cdef extern from "mojo/embedder/platform_support.h" \
+    namespace "mojo::embedder" nogil:
+  cdef cppclass PlatformSupport:
+    pass
+
+cdef extern from "mojo/embedder/simple_platform_support.h" \
+    namespace "mojo::embedder" nogil:
+  cdef cppclass SimplePlatformSupport(PlatformSupport):
+    SimplePlatformSupport()
+
+cdef extern from "mojo/embedder/embedder.h" nogil:
+  cdef void InitCEmbedder "mojo::embedder::Init"(
+      scoped_ptr[PlatformSupport] platform_support)
+
+cdef extern from "mojo/public/platform/native/system_thunks.h" nogil:
+  cdef struct MojoSystemThunks:
+    pass
+  cdef MojoSystemThunks MojoMakeSystemThunks()
+
+def init():
+  InitCEmbedder(scoped_ptr[PlatformSupport](
+      new SimplePlatformSupport()))
+  cdef MojoSystemThunks thunks = MojoMakeSystemThunks()
+  system.set_system_thunks(<uintptr_t>(&thunks))
diff --git a/mojo/python/tests/BUILD.gn b/mojo/python/tests/BUILD.gn
new file mode 100644
index 0000000..0d2949d
--- /dev/null
+++ b/mojo/python/tests/BUILD.gn
@@ -0,0 +1,24 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/cython/rules.gni")
+
+group("tests") {
+  deps = [
+    ":test_core",
+  ]
+}
+
+action("test_core") {
+  script = "test_core.py"
+  outputs = [
+    "$root_out_dir/no_file",
+  ]
+  inputs = []
+  deps = [
+    "//mojo/public/python:system",
+    "//mojo/python:embedder",
+  ]
+  args = [ rebase_path("$root_out_dir/python", root_build_dir) ]
+}
diff --git a/mojo/python/tests/test_core.py b/mojo/python/tests/test_core.py
new file mode 100644
index 0000000..be0253b
--- /dev/null
+++ b/mojo/python/tests/test_core.py
@@ -0,0 +1,314 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import random
+import sys
+import time
+import unittest
+
+# Setup sys path
+for path in sys.argv[1:]:
+  sys.path.append(path)
+
+# pylint: disable=F0401
+from mojo.embedder import init as init_embedder
+from mojo import system
+
+DATA_SIZE = 1024
+
+
+def get_random_buffer(size):
+  random.seed(size)
+  return bytearray(''.join(chr(random.randint(0, 255)) for i in xrange(size)))
+
+
+class BaseMojoTest(unittest.TestCase):
+
+  def setUp(self):
+    init_embedder()
+
+
+class CoreTest(BaseMojoTest):
+
+  def test_results(self):
+    self.assertEquals(system.RESULT_OK, 0)
+    self.assertLess(system.RESULT_CANCELLED, 0)
+    self.assertLess(system.RESULT_UNKNOWN, 0)
+    self.assertLess(system.RESULT_INVALID_ARGUMENT, 0)
+    self.assertLess(system.RESULT_DEADLINE_EXCEEDED, 0)
+    self.assertLess(system.RESULT_NOT_FOUND, 0)
+    self.assertLess(system.RESULT_ALREADY_EXISTS, 0)
+    self.assertLess(system.RESULT_PERMISSION_DENIED, 0)
+    self.assertLess(system.RESULT_RESOURCE_EXHAUSTED, 0)
+    self.assertLess(system.RESULT_FAILED_PRECONDITION, 0)
+    self.assertLess(system.RESULT_ABORTED, 0)
+    self.assertLess(system.RESULT_OUT_OF_RANGE, 0)
+    self.assertLess(system.RESULT_UNIMPLEMENTED, 0)
+    self.assertLess(system.RESULT_INTERNAL, 0)
+    self.assertLess(system.RESULT_UNAVAILABLE, 0)
+    self.assertLess(system.RESULT_DATA_LOSS, 0)
+    self.assertLess(system.RESULT_BUSY, 0)
+    self.assertLess(system.RESULT_SHOULD_WAIT, 0)
+
+  def test_constants(self):
+    self.assertGreaterEqual(system.DEADLINE_INDEFINITE, 0)
+    self.assertGreaterEqual(system.HANDLE_SIGNAL_NONE, 0)
+    self.assertGreaterEqual(system.HANDLE_SIGNAL_READABLE, 0)
+    self.assertGreaterEqual(system.HANDLE_SIGNAL_WRITABLE, 0)
+    self.assertGreaterEqual(system.WRITE_MESSAGE_FLAG_NONE, 0)
+    self.assertGreaterEqual(system.READ_MESSAGE_FLAG_NONE, 0)
+    self.assertGreaterEqual(system.READ_MESSAGE_FLAG_MAY_DISCARD, 0)
+    self.assertGreaterEqual(system.WRITE_DATA_FLAG_NONE, 0)
+    self.assertGreaterEqual(system.WRITE_DATA_FLAG_ALL_OR_NONE, 0)
+    self.assertGreaterEqual(system.READ_DATA_FLAG_NONE, 0)
+    self.assertGreaterEqual(system.READ_DATA_FLAG_ALL_OR_NONE, 0)
+    self.assertGreaterEqual(system.READ_DATA_FLAG_DISCARD, 0)
+    self.assertGreaterEqual(system.READ_DATA_FLAG_QUERY, 0)
+    self.assertGreaterEqual(system.MAP_BUFFER_FLAG_NONE, 0)
+
+  def test_get_time_ticks_now(self):
+    pt1 = time.time()
+    v1 = system.get_time_ticks_now()
+    time.sleep(1e-3)
+    v2 = system.get_time_ticks_now()
+    pt2 = time.time()
+    self.assertGreater(v1, 0)
+    self.assertGreater(v2, v1 + 1000)
+    self.assertGreater(1e6 * (pt2 - pt1), v2 - v1)
+
+  def _test_handles_creation(self, *args):
+    for handle in args:
+      self.assertTrue(handle.is_valid())
+      handle.close()
+      self.assertFalse(handle.is_valid())
+
+  def _test_message_handle_creation(self, handles):
+    self._test_handles_creation(handles.handle0, handles.handle1)
+
+  def test_create_message_pipe(self):
+    self._test_message_handle_creation(system.MessagePipe())
+
+  def test_create_message_pipe_with_none_options(self):
+    self._test_message_handle_creation(system.MessagePipe(None))
+
+  def test_create_message_pipe_with_options(self):
+    self._test_message_handle_creation(
+        system.MessagePipe(system.CreateMessagePipeOptions()))
+
+  def test_wait_over_message_pipe(self):
+    handles = system.MessagePipe()
+    handle = handles.handle0
+
+    self.assertEquals(system.RESULT_OK, handle.wait(
+        system.HANDLE_SIGNAL_WRITABLE, system.DEADLINE_INDEFINITE))
+    self.assertEquals(system.RESULT_DEADLINE_EXCEEDED,
+                      handle.wait(system.HANDLE_SIGNAL_READABLE, 0))
+
+    handles.handle1.write_message()
+
+    self.assertEquals(
+        system.RESULT_OK,
+        handle.wait(
+            system.HANDLE_SIGNAL_READABLE,
+            system.DEADLINE_INDEFINITE))
+
+  def test_wait_over_many_message_pipe(self):
+    handles = system.MessagePipe()
+    handle0 = handles.handle0
+    handle1 = handles.handle1
+
+    self.assertEquals(
+        0,
+        system.wait_many(
+            [(handle0, system.HANDLE_SIGNAL_WRITABLE),
+             (handle1, system.HANDLE_SIGNAL_WRITABLE)],
+            system.DEADLINE_INDEFINITE))
+    self.assertEquals(
+        system.RESULT_DEADLINE_EXCEEDED,
+        system.wait_many(
+            [(handle0, system.HANDLE_SIGNAL_READABLE),
+             (handle1, system.HANDLE_SIGNAL_READABLE)], 0))
+
+    handle0.write_message()
+
+    self.assertEquals(
+        1,
+        system.wait_many(
+            [(handle0, system.HANDLE_SIGNAL_READABLE),
+             (handle1, system.HANDLE_SIGNAL_READABLE)],
+            system.DEADLINE_INDEFINITE))
+
+  def test_send_bytes_over_message_pipe(self):
+    handles = system.MessagePipe()
+    data = get_random_buffer(DATA_SIZE)
+    handles.handle0.write_message(data)
+    (res, buffers, next_message) = handles.handle1.read_message()
+    self.assertEquals(system.RESULT_RESOURCE_EXHAUSTED, res)
+    self.assertEquals(None, buffers)
+    self.assertEquals((DATA_SIZE, 0), next_message)
+    result = bytearray(DATA_SIZE)
+    (res, buffers, next_message) = handles.handle1.read_message(result)
+    self.assertEquals(system.RESULT_OK, res)
+    self.assertEquals(None, next_message)
+    self.assertEquals((data, []), buffers)
+
+  def test_send_empty_data_over_message_pipe(self):
+    handles = system.MessagePipe()
+    handles.handle0.write_message(None)
+    (res, buffers, next_message) = handles.handle1.read_message()
+
+    self.assertEquals(system.RESULT_OK, res)
+    self.assertEquals(None, next_message)
+    self.assertEquals((None, []), buffers)
+
+  def test_send_handle_over_message_pipe(self):
+    handles = system.MessagePipe()
+    handles_to_send = system.MessagePipe()
+    handles.handle0.write_message(handles=[handles_to_send.handle0,
+                                           handles_to_send.handle1])
+    (res, buffers, next_message) = handles.handle1.read_message(
+        max_number_of_handles=2)
+
+    self.assertFalse(handles_to_send.handle0.is_valid())
+    self.assertFalse(handles_to_send.handle1.is_valid())
+    self.assertEquals(system.RESULT_OK, res)
+    self.assertEquals(None, next_message)
+    self.assertEquals(None, buffers[0])
+    self.assertEquals(2, len(buffers[1]))
+
+    handles = buffers[1]
+    for handle in handles:
+      self.assertTrue(handle.is_valid())
+      (res, buffers, next_message) = handle.read_message()
+      self.assertEquals(system.RESULT_SHOULD_WAIT, res)
+
+    for handle in handles:
+      handle.write_message()
+
+    for handle in handles:
+      (res, buffers, next_message) = handle.read_message()
+      self.assertEquals(system.RESULT_OK, res)
+
+  def _test_data_handle_creation(self, handles):
+    self._test_handles_creation(
+        handles.producer_handle, handles.consumer_handle)
+
+  def test_create_data_pipe(self):
+    self._test_data_handle_creation(system.DataPipe())
+
+  def test_create_data_pipe_with_none_options(self):
+    self._test_data_handle_creation(system.DataPipe(None))
+
+  def test_create_data_pipe_with_default_options(self):
+    self._test_data_handle_creation(
+        system.DataPipe(system.CreateDataPipeOptions()))
+
+  def test_create_data_pipe_with_discard_flag(self):
+    options = system.CreateDataPipeOptions()
+    options.flags = system.CreateDataPipeOptions.FLAG_MAY_DISCARD
+    self._test_data_handle_creation(system.DataPipe(options))
+
+  def test_create_data_pipe_with_element_size(self):
+    options = system.CreateDataPipeOptions()
+    options.element_num_bytes = 5
+    self._test_data_handle_creation(system.DataPipe(options))
+
+  def test_create_data_pipe_with_capacity(self):
+    options = system.CreateDataPipeOptions()
+    options.element_capacity_num_bytes = DATA_SIZE
+    self._test_data_handle_creation(system.DataPipe(options))
+
+  def test_create_data_pipe_with_incorrect_parameters(self):
+    options = system.CreateDataPipeOptions()
+    options.element_num_bytes = 5
+    options.capacity_num_bytes = DATA_SIZE
+    with self.assertRaises(system.MojoException) as cm:
+      self._test_data_handle_creation(system.DataPipe(options))
+    self.assertEquals(system.RESULT_INVALID_ARGUMENT, cm.exception.mojo_result)
+
+  def test_send_empty_data_over_data_pipe(self):
+    pipes = system.DataPipe()
+    self.assertEquals((system.RESULT_OK, 0), pipes.producer_handle.write_data())
+    self.assertEquals(
+        (system.RESULT_OK, None), pipes.consumer_handle.read_data())
+
+  def test_send_data_over_data_pipe(self):
+    pipes = system.DataPipe()
+    data = get_random_buffer(DATA_SIZE)
+    self.assertEquals((system.RESULT_OK, DATA_SIZE),
+                      pipes.producer_handle.write_data(data))
+    self.assertEquals((system.RESULT_OK, data),
+                      pipes.consumer_handle.read_data(bytearray(DATA_SIZE)))
+
+  def test_two_phase_write_on_data_pipe(self):
+    pipes = system.DataPipe()
+    (res, buf) = pipes.producer_handle.begin_write_data(DATA_SIZE)
+    self.assertEquals(system.RESULT_OK, res)
+    self.assertGreaterEqual(len(buf.buffer), DATA_SIZE)
+    data = get_random_buffer(DATA_SIZE)
+    buf.buffer[0:DATA_SIZE] = data
+    self.assertEquals(system.RESULT_OK, buf.end(DATA_SIZE))
+    self.assertEquals((system.RESULT_OK, data),
+                      pipes.consumer_handle.read_data(bytearray(DATA_SIZE)))
+
+  def test_two_phase_read_on_data_pipe(self):
+    pipes = system.DataPipe()
+    data = get_random_buffer(DATA_SIZE)
+    self.assertEquals((system.RESULT_OK, DATA_SIZE),
+                      pipes.producer_handle.write_data(data))
+    (res, buf) = pipes.consumer_handle.begin_read_data()
+    self.assertEquals(system.RESULT_OK, res)
+    self.assertEquals(DATA_SIZE, len(buf.buffer))
+    self.assertEquals(data, buf.buffer)
+    self.assertEquals(system.RESULT_OK, buf.end(DATA_SIZE))
+
+  def test_create_shared_buffer(self):
+    self._test_handles_creation(system.create_shared_buffer(DATA_SIZE))
+
+  def test_create_shared_buffer_with_none_options(self):
+    self._test_handles_creation(system.create_shared_buffer(DATA_SIZE, None))
+
+  def test_create_shared_buffer_with_default_options(self):
+    self._test_handles_creation(
+        system.create_shared_buffer(
+            DATA_SIZE,
+            system.CreateSharedBufferOptions()))
+
+  def test_duplicate_shared_buffer(self):
+    handle = system.create_shared_buffer(DATA_SIZE)
+    self._test_handles_creation(handle.duplicate())
+
+  def test_duplicate_shared_buffer_with_none_options(self):
+    handle = system.create_shared_buffer(DATA_SIZE)
+    self._test_handles_creation(handle.duplicate(None))
+
+  def test_duplicate_shared_buffer_with_default_options(self):
+    handle = system.create_shared_buffer(DATA_SIZE)
+    self._test_handles_creation(
+        handle.duplicate(system.DuplicateSharedBufferOptions()))
+
+  def test_send_bytes_over_shared_buffer(self):
+    handle = system.create_shared_buffer(DATA_SIZE)
+    duplicated = handle.duplicate()
+    data = get_random_buffer(DATA_SIZE)
+    (res1, buf1) = handle.map(0, DATA_SIZE)
+    (res2, buf2) = duplicated.map(0, DATA_SIZE)
+    self.assertEquals(system.RESULT_OK, res1)
+    self.assertEquals(system.RESULT_OK, res2)
+    self.assertEquals(DATA_SIZE, len(buf1.buffer))
+    self.assertEquals(DATA_SIZE, len(buf2.buffer))
+    self.assertEquals(buf1.buffer, buf2.buffer)
+
+    buf1.buffer[:] = data
+    self.assertEquals(data, buf1.buffer)
+    self.assertEquals(data, buf2.buffer)
+    self.assertEquals(buf1.buffer, buf2.buffer)
+
+
+if __name__ == '__main__':
+  suite = unittest.TestLoader().loadTestsFromTestCase(CoreTest)
+  test_results = unittest.TextTestRunner(verbosity=0).run(suite)
+  if not test_results.wasSuccessful():
+    sys.exit(1)
+  sys.exit(0)
diff --git a/third_party/cython/cp_python_binary_modules.py b/third_party/cython/cp_python_binary_modules.py
new file mode 100644
index 0000000..dd38e64
--- /dev/null
+++ b/third_party/cython/cp_python_binary_modules.py
@@ -0,0 +1,42 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import argparse
+import os
+import shutil
+import sys
+
+def touch(fname):
+  if os.path.exists(fname):
+    os.utime(fname, None)
+  else:
+    open(fname, 'a').close()
+
+def main():
+  """Command line utility to copy python binary modules to the correct package
+  hierarchy.
+  """
+  parser = argparse.ArgumentParser(
+      description='Copy python binary modules to the correct package '
+                  'hierarchy.')
+  parser.add_argument('timestamp', help='The timetsamp file.')
+  parser.add_argument('lib_dir', help='The directory containing the modules')
+  parser.add_argument('destination_dir',
+                      help='The destination directory of the module')
+  parser.add_argument('mappings', nargs='+',
+                      help='The mapping from module to library.')
+  opts = parser.parse_args()
+
+  if not os.path.exists(opts.destination_dir):
+    os.makedirs(opts.destination_dir)
+
+  for mapping in opts.mappings:
+    [module, library] = mapping.split('=')
+    shutil.copy(os.path.join(opts.lib_dir, library),
+                os.path.join(opts.destination_dir, module))
+
+  touch(opts.timestamp)
+
+if __name__ == '__main__':
+  main()
diff --git a/third_party/cython/cython_compiler.gypi b/third_party/cython/cython_compiler.gypi
new file mode 100644
index 0000000..39d8318
--- /dev/null
+++ b/third_party/cython/cython_compiler.gypi
@@ -0,0 +1,71 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'variables': {
+    'python_flags': '<(DEPTH)/third_party/cython/python_flags.py',
+  },
+  'conditions': [
+    ['OS=="mac"', {
+      'variables': {
+        'module_prefix': '',
+        'module_suffix': '.so',
+      },
+    }, {
+      'variables': {
+        'module_prefix': '<(SHARED_LIB_PREFIX)',
+        'module_suffix': '<(SHARED_LIB_SUFFIX)',
+      },
+    }],
+  ],
+  'type': 'loadable_module',
+  'rules': [
+    {
+      'rule_name': '<(_target_name)_cython_compiler',
+      'extension': 'pyx',
+      'variables': {
+        'cython_compiler': '<(DEPTH)/third_party/cython/src/cython.py',
+      },
+      'inputs': [
+        '<(cython_compiler)',
+      ],
+      'outputs': [
+        '<(SHARED_INTERMEDIATE_DIR)/cython/<(python_base_module)/<(RULE_INPUT_ROOT).cc',
+      ],
+      'action': [
+        'python', '<(cython_compiler)',
+        '--cplus',
+        '-I<(DEPTH)',
+        '-o', '<@(_outputs)',
+        '<(RULE_INPUT_PATH)',
+      ],
+      'message': 'Generating C++ source from <(RULE_INPUT_PATH)',
+      'process_outputs_as_sources': 1,
+    }
+  ],
+  'include_dirs': [
+    '<!@(python <(python_flags) --includes)',
+    '<(DEPTH)',
+  ],
+  'libraries': [
+    '<!@(python <(python_flags) --libraries)',
+  ],
+  'cflags': [
+    '-Wno-unused-function',
+  ],
+  'xcode_settings': {
+    'WARNING_CFLAGS': [ '-Wno-unused-function' ],
+  },
+  'library_dirs': [
+    '<!@(python <(python_flags) --library_dirs)',
+  ],
+  'direct_dependent_settings': {
+    'variables': {
+      'python_binary_modules': [
+        '<(python_cython_module)<(module_suffix)=<(module_prefix)<(_target_name)<(module_suffix)',
+      ],
+    },
+  },
+  'hard_dependency': 1,
+}
diff --git a/third_party/cython/python_export.h b/third_party/cython/python_export.h
new file mode 100644
index 0000000..e943399
--- /dev/null
+++ b/third_party/cython/python_export.h
@@ -0,0 +1,13 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#if defined(PyMODINIT_FUNC)
+#undef PyMODINIT_FUNC
+#endif
+
+#if defined(WIN32)
+#define PyMODINIT_FUNC extern "C" __declspec(dllexport) void
+#else
+#define PyMODINIT_FUNC extern "C" __attribute__((visibility("default"))) void
+#endif
diff --git a/third_party/cython/python_flags.py b/third_party/cython/python_flags.py
new file mode 100644
index 0000000..03c4ad7
--- /dev/null
+++ b/third_party/cython/python_flags.py
@@ -0,0 +1,53 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import argparse
+import os
+import sys
+
+from distutils import sysconfig
+from distutils.command import build_ext
+from distutils.dist import Distribution
+from distutils.extension import Extension
+
+def main():
+  """Command line utility to retrieve compilation options for python modules'
+  """
+  parser = argparse.ArgumentParser(
+      description='Retrieves compilation options for python modules.')
+  parser.add_argument('--gn',
+                      help='Returns all values in a format suitable for gn',
+                      action='store_true')
+  parser.add_argument('--libraries', help='Returns libraries',
+                      action='store_true')
+  parser.add_argument('--includes', help='Returns includes',
+                      action='store_true')
+  parser.add_argument('--library_dirs', help='Returns library_dirs',
+                      action='store_true')
+  opts = parser.parse_args()
+
+  ext = Extension('Dummy', [])
+  b = build_ext.build_ext(Distribution())
+  b.initialize_options()
+  b.finalize_options()
+  result = []
+  if opts.libraries:
+    libraries = b.get_libraries(ext)
+    if sys.platform == 'darwin':
+      libraries += [ '-lpython%s' % sys.version[:3] ]
+    result = result + libraries
+  if opts.includes:
+    result = result  + b.include_dirs
+  if opts.library_dirs:
+    if sys.platform == 'darwin':
+      result.append('%s/lib' % sysconfig.get_config_vars('prefix')[0])
+
+  if opts.gn:
+    for x in result:
+      print x
+  else:
+    print ''.join(['"%s"' % x for x in result])
+
+if __name__ == '__main__':
+  main()
diff --git a/third_party/cython/python_module.gypi b/third_party/cython/python_module.gypi
new file mode 100644
index 0000000..a61ca2d
--- /dev/null
+++ b/third_party/cython/python_module.gypi
@@ -0,0 +1,51 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'variables': {
+    'python_binary_modules%': [],
+    'python_module_destination': '<(PRODUCT_DIR)/python/<(python_base_module)',
+    'cp': '<(DEPTH)/third_party/cython/cp_python_binary_modules.py',
+    'timestamp': '<(SHARED_INTERMEDIATE_DIR)/<(_target_name)_py_module.stamp',
+  },
+  'rules': [
+    {
+      'rule_name': '<(_target_name)_cp_python',
+      'extension': 'py',
+      'inputs': [
+        '<(DEPTH)/build/cp.py',
+      ],
+      'outputs': [
+        '<(python_module_destination)/<(RULE_INPUT_NAME)',
+      ],
+      'action': [
+        'python',
+        '<@(_inputs)',
+        '<(RULE_INPUT_PATH)',
+        '<@(_outputs)',
+      ],
+      'message': 'Moving <(RULE_INPUT_PATH) to its destination',
+    }
+  ],
+  'actions': [
+    {
+      'action_name': '<(_target_name)_move_to_python_modules',
+      'inputs': [
+        '<(cp)',
+      ],
+      'outputs': [
+        '<(timestamp)',
+      ],
+      'action': [
+        'python',
+        '<(cp)',
+        '<(timestamp)',
+        '<(PRODUCT_DIR)',
+        '<(python_module_destination)',
+        '>@(python_binary_modules)',
+      ],
+    },
+  ],
+  'hard_dependency': 1,
+}
diff --git a/third_party/cython/rules.gni b/third_party/cython/rules.gni
new file mode 100644
index 0000000..22a56c3
--- /dev/null
+++ b/third_party/cython/rules.gni
@@ -0,0 +1,84 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+template("python_binary_module") {
+  # Only available on linux for now.
+  assert(is_linux)
+  assert(defined(invoker.sources))
+  assert(defined(invoker.python_base_module))
+
+  cython_root = "//third_party/cython"
+  cython_script = "$cython_root/src/cython.py"
+  cython_output = "${target_out_dir}/${target_name}.cc"
+
+  generator_target_name = target_name + "_cython_compiler"
+  shared_library_name = target_name + "_shared_library"
+  config_name = target_name + "_python_config"
+
+  if (is_linux) {
+    shared_library_prefix = "lib"
+    shared_library_suffix = ".so"
+    python_module_suffix = ".so"
+  }
+
+  target_visibility = [
+    ":$generator_target_name",
+    ":$shared_library_name",
+    ":$target_name",
+  ]
+
+  action(generator_target_name) {
+    visibility = target_visibility
+    script = cython_script
+    sources = invoker.sources
+    outputs = [ cython_output ]
+    args = [
+      "--cplus",
+      "-I", rebase_path("//", root_build_dir),
+      "-o", rebase_path(cython_output, root_build_dir),
+    ] + rebase_path(sources, root_build_dir)
+  }
+
+  config(config_name) {
+    visibility = target_visibility
+    python_flags = "//third_party/cython/python_flags.py"
+    include_dirs = exec_script(python_flags,
+                               [ "--gn", "--includes" ],
+                               "list lines")
+    libs = exec_script(python_flags,
+                       [ "--gn", "--libraries" ],
+                       "list lines")
+    lib_dirs = exec_script(python_flags,
+                           [ "--gn", "--library_dirs" ],
+                           "list lines")
+  }
+
+  shared_library(shared_library_name) {
+    visibility = target_visibility
+    deps = [
+      ":$generator_target_name",
+    ]
+    if (defined(invoker.deps)) {
+      deps += invoker.deps
+    }
+    if (defined(invoker.datadeps)) {
+      datadeps = invoker.datadeps
+    }
+    sources = [ cython_output ]
+    configs += [ ":$config_name" ]
+  }
+
+  copy(target_name) {
+    python_base_module = invoker.python_base_module
+    sources = [
+      "$root_out_dir/${shared_library_prefix}${shared_library_name}${shared_library_suffix}"
+    ]
+    outputs = [
+      "$root_out_dir/python/$python_base_module/${target_name}${python_module_suffix}"
+    ]
+    deps = [
+      ":$shared_library_name"
+    ]
+  }
+}