Bug 1585015

Created attachment 1446542 [details]
The patch fixes the issues.

Description of problem:

gmond system metric module returns uninitialized local variable value for machine_type metric, which causes gmetad fails to parse the data. As a result, no metric data can be saved.

Version-Release number of selected component (if applicable): 

It's 3.7.2.

# yum info ganglia-gmond
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * epel: mirrors.sohu.com
 * epel-debuginfo: mirrors.tongji.edu.cn
Installed Packages
Name        : ganglia-gmond
Arch        : aarch64
Version     : 3.7.2
Release     : 2.el7
Size        : 295 k
Repo        : installed
From repo   : epel
Summary     : Ganglia Monitoring daemon
URL         : http://ganglia.sourceforge.net/
License     : BSD
Description : Ganglia is a scalable, real-time monitoring and execution environment
            : with all execution requests and statistics expressed in an open
            : well-defined XML format.
            : 
            : This gmond daemon provides the ganglia service within a single cluster or
            : Multicast domain.


How reproducible:


Steps to Reproduce:

1. Make sure gmond service is started

2. Get machine_type metric value by using nc

$ nc localhost 8649 | grep machine_type
<METRIC NAME="machine_type" VAL="I&#30;&#13;[" TYPE="string" UNITS="" TN="19" TMAX="1200" DMAX="0" SLOPE="zero">
^C

Note the value above, it's garbage.

3. Start the Python version of gmetad in debug mode. It will dump error message on screen, like the following:

Exception in thread Thread-3:
Traceback (most recent call last):
  File "/usr/lib64/python2.7/threading.py", line 812, in __bootstrap_inner
    self.run()
  File "/root/osgcloud/cbtool/3rd_party/monitor-core/gmetad-python/Gmetad/gmetad_gmondReader.py", line 140, in run
    xml.sax.parseString(xmlbuf, gch)
  File "/usr/lib64/python2.7/xml/sax/__init__.py", line 49, in parseString
    parser.parse(inpsrc)
  File "/usr/lib64/python2.7/xml/sax/expatreader.py", line 107, in parse
    xmlreader.IncrementalParser.parse(self, source)
  File "/usr/lib64/python2.7/xml/sax/xmlreader.py", line 123, in parse
    self.feed(buffer)
  File "/usr/lib64/python2.7/xml/sax/expatreader.py", line 214, in feed
    self._err_handler.fatalError(exc)
  File "/usr/lib64/python2.7/xml/sax/handler.py", line 38, in fatalError
    raise exception
SAXParseException: <unknown>:252:34: reference to invalid character number

The invalid charcter in question is the "I&#30;&#13;[" string shown in step 2.

Query gmetad as below, it outputs nothing because the exception above prevents it from saving any metric data.

$ nc localhost 8651


Actual results:

See abvoe

Expected results:

It should returns "aarch64" on aarch64 platform, or "unknown" on unsupported platform.

Additional info:

The fix is attached.