[Libguestfs] [nbdkit] can't import mmap

[Richard W.M. Jones]

On Thu, Oct 29, 2015 at 09:19:03AM -0500, Jason Pepas wrote:
> Hi,
> 
> I'm new to nbdkit and am trying to run a simple "single file block
> device using mmap" setup, using this python script:
> 
> import mmap
> 
> def config(key, value):
>     print ("ignored parameter %s=%s" % (key, value))
> 
> def open(readonly):
>     print ("open: readonly=%d" % readonly)
>     f = open("disk","r+")
>     m = mmap.mmap(f.fileno(), 0, access=mmap.ACCESS_WRITE)
>     return (f,m)
> 
> def get_size(h):
>     size = 1024*1024
> 
> def pread(h, count, offset):
>     (f,m) = h
>     bytes = bytearray(m[offset:offset+count])
>     return bytes
> 
> def pwrite(h, buf, offset):
>     (f,m) = h
>     m[offset:offset+len(buf)] = bytearray(buf)
> 
> 
> When I run this:
> 
> /usr/sbin/nbdkit -f -v python script=single_file.py
> 
> 
> I get this error:
> 
> nbdkit: debug: registering
> /usr/lib/x86_64-linux-gnu/nbdkit/plugins/nbdkit-python-plugin.so
> nbdkit: debug: registered
> /usr/lib/x86_64-linux-gnu/nbdkit/plugins/nbdkit-python-plugin.so (name
> python)
> nbdkit: debug: /usr/lib/x86_64-linux-gnu/nbdkit/plugins/nbdkit-python-plugin.so:
> load
> nbdkit: debug: /usr/lib/x86_64-linux-gnu/nbdkit/plugins/nbdkit-python-plugin.so:
> config key=script, value=single_file.py
> Traceback (most recent call last):
>   File "single_file.py", line 1, in <module>
>     import mmap
> ImportError: /usr/lib/python2.7/lib-dynload/mmap.x86_64-linux-gnu.so:
> undefined symbol: PyExc_SystemError
> nbdkit: error: single_file.py: error running this script
> 
> 
> Any ideas?

It's probably this bug:

https://bugzilla.redhat.com/1223870

Fixed in this commit:

https://github.com/libguestfs/nbdkit/commit/77f4982e65840b6edff5e97d3dbdf140f7e3229b

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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