New issue 2588: ctypes package error: "TypeError: expected a readable buffer object" https://bitbucket.org/pypy/pypy/issues/2588/ctypes-package-error-typeerror-expected-a
MilesCranmer: I am trying out PyPy on the following python 2.7 package (written with ctypes calls): https://github.com/ledatelescope/bifrost. Everything installs correctly. However, in running the test suite, I get the following errors (about 2/3 of the tests have this error): ``` #!python Exception in thread Pipeline_0/SigprocSourceBlock_0: Traceback (most recent call last): File "/workspace/pypy2-v5.8.0-linux64/lib-python/2.7/threading.py", line 797, in __bootstrap_inner self.run() File "/workspace/pypy2-v5.8.0-linux64/lib-python/2.7/threading.py", line 750, in run self.__target(*self.__args, **self.__kwargs) File "build/bdist.linux-x86_64/egg/bifrost/pipeline.py", line 308, in run self.main(active_orings) File "build/bdist.linux-x86_64/egg/bifrost/pipeline.py", line 380, in main ostrides = self.on_data(ireader, ospans) File "build/bdist.linux-x86_64/egg/bifrost/blocks/sigproc.py", line 109, in on_data ospan.data[:nframe] = indata File "build/bdist.linux-x86_64/egg/bifrost/ring2.py", line 399, in data dtype=self.dtype) File "build/bdist.linux-x86_64/egg/bifrost/ndarray.py", line 224, in __new__ data_buffer, offset, strides) TypeError: expected a readable buffer object ``` The minimal reproducible code is: ``` #!python >>>> import bifrost >>>> from bifrost import blocks as blocks >>>> from bifrost import pipeline as bfp >>>> with bfp.Pipeline() as pipeline: .... blocks.read_sigproc(['data/2chan4bitNoDM.fil'], 4096) .... pipeline.run() ``` This reads in a file from "data" into the pipeline class, which calls a C++ backend to allocate a ring buffer and put the data on it. The relevant code where the error is: https://github.com/ledatelescope/bifrost/blob/master/python/bifrost/ndarray.py ``` #!python BufferType = ctypes.c_byte*nbyte data_buffer_ptr = ctypes.cast(buffer, ctypes.POINTER(BufferType)) data_buffer = data_buffer_ptr.contents obj = np.ndarray.__new__(cls, shape, dtype_np, data_buffer, offset, strides) obj.bf = BFArrayInfo(space, dtype, native, conjugated, ownbuffer) obj._update_BFarray() ``` Please let me know if you would like any other info. Here are some system stats: ``` ➜ test git:(master) ✗ pypy --version Python 2.7.13 (c925e7381036, Jun 05 2017, 21:20:51) [PyPy 5.8.0 with GCC 6.2.0 20160901] ``` ``` ➜ test git:(master) ✗ uname -a Linux 004a0c817a24 4.9.27-14.31.amzn1.x86_64 #1 SMP Wed May 10 01:58:40 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux ``` This is running inside a Docker (which is running Ubuntu 16.04). You can try this package with: ``` docker pull mcranmer/bifrost:cpu-base ``` Then, clone Bifrost and install it with pypy. _______________________________________________ pypy-issue mailing list pypy-issue@python.org https://mail.python.org/mailman/listinfo/pypy-issue
