Bug 950419

+++ This bug was initially created as a clone of Bug #912172 +++

the problem also on:
libvirt-1.0.2-1.el7.x86_64
libvirt-python-1.0.2-1.el7.x86_64

+++ This bug was initially created as a clone of Bug #912170 +++

Description of problem:
memoryStats fail did not raise libvirtError 

# python
Python 2.7.3 (default, Aug 10 2012, 02:54:27)
[GCC 4.7.1 20120720 (Red Hat 4.7.1-5)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import libvirt
>>> con = libvirt.open(None)
>>> dom = con.lookupByName('test')
>>> dom.memoryStats()
libvir: QEMU Driver error : Requested operation is not valid: domain is not running

user will fail to catch exception. 

Version-Release number of selected component (if applicable):
libvirt-0.10.2-18.el6.x86_64 

How reproducible:
always

Steps to Reproduce:
1. as description 
2.
3.
  
Actual results:
memoryStats fail did not raise libvirtError 

Expected results:
memoryStats fail raise libvirtError

>>> dom.memoryStats()
libvir: QEMU Driver error : Requested operation is not valid: domain is not running
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1981, in memoryStats
    if ret is None: raise libvirtError ('virDomainMemoryStats() failed', dom=self)
libvirt.libvirtError: Requested operation is not valid: domain is not running


--- Additional comment from Gunannan Ren on 2013-03-20 23:25:41 EDT ---

commit 4b143ab23173000d1afa258726be0ff38cf2b386
Author: Guannan Ren <gren>
Date:   Thu Mar 21 11:24:49 2013 +0800

    python: fix bindings that don't raise an exception
    
    For example:
     >>> dom.memoryStats()
     libvir: QEMU Driver error : Requested operation is not valid:\
             domain is not running
    
    There are six such python API functions like so.
    The root reason is that generator.py script checks the type of return
    value of a python stub function defined in libvirt-api.xml or
    libvirt-override-api.xml to see whether to add the raise clause or not
    in python wrapper code in libvirt.py.
    
    The type of return value is supposed to be C types.
    For those stub functions which return python non-integer data type like
    string, list, tuple, dictionary, the existing type in functions varies
    from each other which leads problem like this.
    
    Currently, in generator.py, it maintains a buggy whitelist for stub functions
    returning a list type. I think it is easy to forget adding new function name
    in the whitelist.
    
    This patch makes the value of type consistent with C type "char *"
    in libvirt-override-api.xml. For python, any of types could be printed
    as string, so I choose "char *" in this case. And the comment in xml
    could explain it when adding new function definition.
    
          <function name='virNodeGetCPUStats' file='python'>
            ...
     -      <return type='virNodeCPUStats' info='...'/>
     +      <return type='char *' info='...'/>
            ...
          </function>

--- Additional comment from Wayne Sun on 2013-04-10 03:43:44 EDT ---

pkgs:
libvirt-1.0.4-1.el7.x86_64
libvirt-python-1.0.4-1.el7.x86_64
kernel-3.7.0-0.32.el7.x86_64
qemu-kvm-1.4.0-2.el7.x86_64

steps:

As far all affected API works fine except for blockJobInfo:

# virsh blockjob aa hda;echo $?

0

>>> dom1.blockJobInfo('hda')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1909, in blockJobInfo
    if ret is None: raise libvirtError ('virDomainGetBlockJobInfo() failed', dom=self)
libvirt.libvirtError: virDomainGetBlockJobInfo() failed
>>> 

the return is None as no block job running, virsh not fail but python will raise exception.

--- Additional comment from Gunannan Ren on 2013-04-10 04:28:50 EDT ---


> >>> dom1.blockJobInfo('hda')
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
>   File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1909, in
> blockJobInfo
>     if ret is None: raise libvirtError ('virDomainGetBlockJobInfo() failed',
> dom=self)
> libvirt.libvirtError: virDomainGetBlockJobInfo() failed
> >>> 
> 
> the return is None as no block job running, virsh not fail but python will
> raise exception.

The virDomainGetBlockJobInfo API 
Returns -1 in case of failure, 0 when nothing found, 1 when info was found.

But in the python C stub, it doesn't distinguish the case of failure from nothing found like, I think there is a new bug found.

if (c_ret != 1)
   return VIR_PY_NONE;