Merge 4fb07db into a6f6a72

setup.py

@@ -70,6 +70,7 @@
 extra_compile_args = []
 cython_directives = {}
 cython_line_directives = {}
+cython_compile_time_env = {"PY_VERSION_HEX": sys.hexversion}
 
 
 if "test" in sys.argv:
@@ -99,6 +100,7 @@
 for em in ext_modules:
     em.cython_directives = dict(cython_directives)
     em.cython_line_directives = dict(cython_line_directives)
+    em.cython_compile_time_env = dict(cython_compile_time_env)
 
 
 setup(

src/pysharedmem.pyx

@@ -1,3 +1,94 @@
+# cython: boundscheck = False
+# cython: initializedcheck = False
+# cython: nonecheck = False
+# cython: wraparound = False
+
+
+cimport cpython
+cimport cpython.buffer
+cimport cpython.bytes
+cimport cpython.object
+cimport cpython.tuple
+
+from cpython.buffer cimport PyBuffer_ToContiguous
+from cpython.bytes cimport PyBytes_FromStringAndSize
+from cpython.object cimport PyObject
+from cpython.tuple cimport PyTuple_Pack
+
 cimport pysharedmem
 
 include "version.pxi"
+
+
+cdef extern from "Python.h":
+    IF PY_VERSION_HEX >= 0x03040000:
+        void* PyMem_RawMalloc(size_t n) nogil
+        void PyMem_RawFree(void *p) nogil
+    ELSE:
+        void* PyMem_RawMalloc "PyMem_Malloc" (size_t n) nogil
+        void PyMem_RawFree "PyMem_Free" (void *p) nogil
+
+cdef extern from "Python.h":
+    object PyMemoryView_FromObject(object)
+    Py_buffer* PyMemoryView_GET_BUFFER(object)
+
+
+cdef class cbuffer:
+    cdef char[::1] buf
+
+    def __cinit__(self, Py_ssize_t length):
+        self.buf = None
+
+        if length <= 0:
+            raise ValueError("length must be positive definite")
+
+        cdef char* ptr = <char*>PyMem_RawMalloc(length * sizeof(char))
+        if not ptr:
+            raise MemoryError("unable to allocate buffer")
+
+        self.buf = <char[:length]>ptr
+
+    def __getbuffer__(self, Py_buffer *buffer, int flags):
+        buffer.buf = &self.buf[0]
+        buffer.obj = self
+        buffer.len = len(self.buf)
+        buffer.readonly = 0
+        buffer.itemsize = self.buf.itemsize
+        buffer.format = "c"
+        buffer.ndim = self.buf.ndim
+        buffer.shape = self.buf.shape
+        buffer.strides = self.buf.strides
+        buffer.suboffsets = NULL
+        buffer.internal = NULL
+
+    def __releasebuffer__(self, Py_buffer *buffer):
+        pass
+
+    def __reduce__(self):
+        cdef bytes buf_bytes = PyBytes_FromStringAndSize(
+            &self.buf[0], len(self.buf)
+        )
+
+        cdef tuple result = PyTuple_Pack(1, <PyObject*>buf_bytes)
+        result = PyTuple_Pack(2, <PyObject*>frombuffer, <PyObject*>result)
+
+        return result
+
+    def __dealloc__(self):
+        cdef char* ptr
+        if self.buf is not None:
+            ptr = &self.buf[0]
+            self.buf = None
+            PyMem_RawFree(<void*>ptr)
+
+
+def frombuffer(src):
+    src = PyMemoryView_FromObject(src)
+    cdef Py_buffer* src_buf = PyMemoryView_GET_BUFFER(src)
+
+    cdef cbuffer dest = cbuffer(src_buf.len)
+    cdef char* dest_ptr = &dest.buf[0]
+
+    PyBuffer_ToContiguous(<void*>dest_ptr, src_buf, src_buf.len, 'C')
+
+    return dest

tests/test_pysharedmem.py

@@ -3,12 +3,125 @@
 
 from __future__ import absolute_import
 
+import pickle
+import sys
 import unittest
 
 
-class TestImportTopLevel(unittest.TestCase):
-    def runTest(self):
+try:
+    unichr
+except NameError:
+    unichr = chr
+
+
+class TestPySharedMem(unittest.TestCase):
+    def test_import(self):
         try:
             import pysharedmem
         except ImportError:
             self.fail("Unable to import `pysharedmem`.")
+
+
+    def test_create_empty_mem(self):
+        import pysharedmem
+        with self.assertRaises(ValueError):
+            pysharedmem.cbuffer(0)
+
+
+    def test_create_negative_mem(self):
+        import pysharedmem
+        with self.assertRaises(ValueError):
+            pysharedmem.cbuffer(-1)
+
+
+    def test_create_singleton_mem(self):
+        import pysharedmem
+        pysharedmem.cbuffer(1)
+
+
+    def test_memoryview(self):
+        import pysharedmem
+
+        l = 3
+        b = pysharedmem.cbuffer(l)
+
+        m = memoryview(b)
+
+        self.assertEqual(m.readonly, False)
+
+        self.assertEqual(m.format, 'c')
+        self.assertEqual(m.itemsize, 1)
+
+        self.assertEqual(m.ndim, 1)
+        self.assertEqual(m.shape, (l,))
+        self.assertEqual(m.strides, (1,))
+
+        if sys.version_info[0] >= 3:
+            self.assertEqual(m.suboffsets, ())
+        else:
+            self.assertEqual(m.suboffsets, None)
+
+
+    @unittest.skipIf(sys.version_info[0] < 3,
+                     "This test requires Python 3.")
+    def test_memoryview_py3(self):
+        import pysharedmem
+
+        l = 3
+        b = pysharedmem.cbuffer(l)
+
+        m = memoryview(b)
+
+        self.assertIs(m.obj, b)
+
+        self.assertTrue(m.c_contiguous)
+        self.assertTrue(m.contiguous)
+        self.assertTrue(m.f_contiguous)
+
+        self.assertEqual(m.readonly, False)
+
+        self.assertEqual(m.format, 'c')
+        self.assertEqual(m.itemsize, 1)
+
+        self.assertEqual(m.ndim, 1)
+        self.assertEqual(m.nbytes, l)
+        self.assertEqual(m.shape, (l,))
+        self.assertEqual(m.strides, (1,))
+        self.assertEqual(m.suboffsets, ())
+
+
+    def test_assignment(self):
+        import pysharedmem
+
+        l = 3
+        b = pysharedmem.cbuffer(l)
+
+        m = memoryview(b)
+        for i in range(len(m)):
+            m[i] = unichr(i).encode("utf-8")
+
+        a1 = bytearray(m)
+        a2 = bytearray(b)
+
+        self.assertIsNot(a1, a2)
+        self.assertEqual(a1, a2)
+
+
+    def test_pickle(self):
+        import pysharedmem
+
+        l = 3
+        b1 = pysharedmem.cbuffer(l)
+
+        m = memoryview(b1)
+        for i in range(len(m)):
+            m[i] = unichr(i).encode("utf-8")
+
+        b2 = pickle.loads(pickle.dumps(b1))
+
+        a1 = bytes(memoryview(b1))
+        a2 = bytes(memoryview(b2))
+
+        self.assertIsNot(b1, b2)
+        self.assertIsNot(a1, a2)
+        self.assertEqual(a1, a2)