This is a feature and bugfix release.

Broker

  • Add $SYS/broker/messages/dropped
  • Add $SYS/broker/clients/expired
  • Replace $SYS/broker/+/per second/+ with moving average versions published at $SYS/broker/load/#
  • Add $SYS/broker/load/sockets/+ and $SYS/broker/load/connections/+
  • Documentation on password file format has been fixed.
  • Disable SSL compression. This reduces memory usage significantly and removes the possibility of CRIME type attacks.
  • Enable SSL_MODE_RELEASE_BUFFERS mode to reduce SSL memory usage further.
  • Add allow_duplicate_messages option.
  • ACL files can now have comment lines with # as the first character.
  • Display message on startup about which config is being loaded.
  • Fix max_inflight_messages and max_queued_messages not being applied.
  • Fix documentation error in mosquitto.conf.
  • Ensure that QoS 2 queued messages are sent out in a timely manner.
  • Local bridges now act on clean_session correctly.
  • Local bridges with clean_session==false now remove unused subscriptions on broker restart.
  • The $SYS/broker/heap/# messages now no longer include “bytes” as part of the string for ease of use.

Client library

  • Free memory used by OpenSSL in mosquitto_lib_cleanup() where possible.
  • Change WebSocket subprotocol name to mqttv3.1 to make future changes easier and for compatibility with other implementations.
  • mosquitto_loop_read() and mosquitto_loop_write() now handle errors themselves rather than having mosquitto_loop() handle their errors. This makes using them in a separate event loop more straightforward.
  • Add mosquitto_loop_forever() / loop_forever() function call to make simple clients easier.
  • Disable SSL compression. This reduces memory usage significantly and removes the possibility of CRIME type attacks.
  • Enable SSL_MODE_RELEASE_BUFFERS mode to reduce SSL memory usage further.
  • mosquitto_tls_set() will now return an error or raise an exception immediately if the CA certificate or client certificate/key cannot be accessed.
  • Fix potential memory leaks on connection failures.
  • Don’t produce return error from mosquitto_loop() if a system call is interrupted. This prevents disconnects/reconnects in threaded mode and simplifies non-threaded client handling.
  • Ignore SIGPIPE to prevent unnecessary client quits in threaded mode.
  • Fix document error for mosquitto_message_retry_set().
  • Fix mosquitto_topic_matches_sub() for subscriptions with + as the final character. Fixes bug #1085797.
  • Rename all “obj” parameters to “userdata” for consistency with other libraries.
  • Reset errno before network read/write to ensure EAGAIN isn’t mistakenly returned.
  • The message queue length is now tracked and used to determine the maximum number of packets to process at once. This removes the need for the max_packets parameter which is now unused.
  • Fix incorrect error value in Python error_string() function. Fixes bug #1086777.
  • Reset last message in/out timer in Python module when we send a PINGREQ. Fixes too-early disconnects.

Clients

  • Clients now display their own version number and library version number in their help messages.
  • Fix “mosquitto_pub -l -q 2” disconnecting before all messages were transmitted.
  • Fix potential out-of-bounds array access with client ids. Fixes bug #1083182.

Other

  • mosquitto_passwd can now convert password files with plain text files to hashed versions.