In PhutilLogFileChannel, don't log empty messages

Authored by epriestley on Feb 16 2017, 1:50 PM.



Ref T2794. The LogFile channel is used to debug another channel by sending all the messages to a logfile.

We perform empty (zero-length) reads over nonblocking channels in various reasonable situations. Currently, these get written to the logfile as empty lines. However, they are probably never useful.

Instead, only write data if it has nonzero length.

Test Plan

After this change, debugging output from the experimental Phage stuff no longer fills up the protocol logfile with tons of empty messages.

Diff Detail

rPHU libphutil
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epriestley created this revision.Feb 16 2017, 1:50 PM
chad accepted this revision.Feb 17 2017, 11:57 PM
This revision is now accepted and ready to land.Feb 17 2017, 11:57 PM
This revision was automatically updated to reflect the committed changes.