The patch for https://issues.apache.org/jira/browse/MAPREDUCE-2254 required minor changes to the LineReader class to allow extensions (see attached 2.patch). Description copied below:
It will be useful to allow setting the end-of-record delimiter for TextInputFormat. The current implementation hardcodes '\n', '\r' or '\r\n' as the only possible record delimiters. This is a problem if users have embedded newlines in their data fields (which is pretty common). This is also a problem for other tools using this TextInputFormat (See for example: https://issues.apache.org/jira/browse/PIG-836 and https://issues.cloudera.org/browse/SQOOP-136).
I have wrote a patch to address this issue. This patch allows users to specify any custom end-of-record delimiter using a new added configuration property. For backward compatibility, if this new configuration property is absent, then the same exact previous delimiters are used (i.e., '\n', '\r' or '\r\n').