changes-1.0.3-1.0.4.xml

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<group from="1.0.3" to="1.0.4">
  <subsystem>
    <name>varnishd</name>

    <change type="enh,bug" ref="1277">
      <para>The request workflow has been redesigned to simplify
      request processing and eliminate code duplication.  All
      codepaths which need to speak HTTP now share a single
      implementation of the protocol.  Some new VCL hooks have been
      added, though they aren't much use yet.  The only real
      user-visible change should be that Varnish now handles
      persistent backend connections correctly (see <ticket
      ref="56"/>).</para>
    </change>

    <change type="enh" ref="1280">
      <para>Support for multiple listen addresses has been
      added.</para>
    </change>

    <change type="enh" ref="1281">
      <para>An "include" facility has been added to VCL, allowing
      VCL code to pull in code fragments from multiple files.</para>
    </change>

    <change type="enh" ref="1284">
      <para>Multiple definitions of the same VCL function are now
      concatenated into one in the order in which they appear in the
      source.  This simplifies the mechanism for falling back to the
      built-in default for cases which aren't handled in custom
      code, and facilitates modularization.</para>
    </change>

    <change type="bug" ref="1287,1288">
      <para>The code used to format management command arguments
      before passing them on to the child process would
      underestimate the amount of space needed to hold each argument
      once quotes and special characters were properly escaped,
      resulting in a buffer overflow.  This has been
      corrected.</para>
    </change>

    <change type="enh,bug" ref="1289-1291,1294,1296-1303,1306">
      <para>The VCL compiler has been overhauled.  Several memory
      leaks have been plugged, and error detection and reporting has
      been improved throughout.  Parts of the compiler have been
      refactored to simplify future extension of the
      language.</para>
    </change>

    <change type="bug" ref="1293">
      <para>A bug in the VCL compiler which resulted in incorrect
      parsing of the decrement (<code>-=</code>) operator has been
      fixed.</para>
    </change>

    <change type="enh" ref="1309,1312,1381">
      <para>A new <code>-C</code> command-line option has been added
      which causes <code>varnishd</code> to compile the VCL code
      (either from a file specified with <code>-f</code> or the
      built-in default), print the resulting C code and exit.</para>
    </change>

    <change type="bug" ref="1359">
      <para>When processing a backend response using chunked
      encoding, if a chunk header crosses a read buffer boundary,
      read additional bytes from the backend connection until the
      chunk header is complete.</para>
    </change>

    <change type="enh" ref="1373">
      <para>A new <code>ping_interval</code> run-time parameter
      controls how often the management process checks that the
      worker process is alive.</para>
    </change>

    <change type="bug" ref="1376">
      <para>A bug which would cause the worker process to
      dereference a <code>NULL</code> pointer and crash if the
      backend did not respond has been fixed.</para>
    </change>

    <change type="bug" ref="1382">
      <para>In some cases, such as when they are used by AJAX
      applications to circumvent Internet Explorer's over-eager disk
      cache, it may be desirable to cache <code>POST</code>
      requests.  However, the code path responsible for delivering
      objects from cache would only transmit the response body when
      replying to a <code>GET</code> request.  This has been
      extended to also apply to <code>POST</code>.</para>

      <para>This should be revisited at a later date to allow VCL
      code to control whether the body is delivered.</para>
    </change>

    <change type="bug" ref="1386">
      <para>Varnish now respects <code>Cache-control:
      s-maxage</code>, and prefers it to <code>Cache-control:
      max-age</code> if both are present.</para>

      <para>This should be revisited at a later date to allow VCL
      code to control which headers are used and how they are
      interpreted.</para>
    </change>

    <change type="enh" ref="1394">
      <para>When loading a new VCL script, the management process
      will now load the compiled object to verify that it links
      correctly before instructing the worker process to load
      it.</para>
    </change>

    <change type="enh" ref="1415">
      <para>A new <code>-P</code> command-line options has been
      added which causes <code>varnishd</code> to create a PID
      file.</para>
    </change>

    <change type="bug" ref="1417">
      <para>The <code>sendfile_threshold</code> run-time parameter's
      default value has been set to infinity after a variety of
      <code>sendfile()</code>-related bugs were discovered on
      several platforms.</para>
    </change>
  </subsystem>

  <subsystem>
    <name>varnishlog</name>

    <change type="bug" ref="1372,1374">
      <para>When grouping log entries by request,
      <code>varnishlog</code> attempts to collapse the log entry for
      a call to a VCL function with the log entry for the
      corresponding return from VCL.  When two VCL calls were made
      in succession, <code>varnishlog</code> would incorrectly omit
      the newline between the two calls (see <ticket
      ref="95"/>).</para>
    </change>

    <change type="enh" ref="1411">
      <para>New <code>-D</code> and <code>-P</code> command-line
      options have been added to daemonize and create a pidfile,
      respectively.</para>
    </change>

    <change type="bug" ref="1450">
      <para>The flag that is raised upon reception of a
      <code>SIGHUP</code> has been marked <code>volatile</code> so it
      will not be optimized away by the compiler.</para>
    </change>
  </subsystem>

  <subsystem>
    <name>varnishncsa</name>

    <change type="enh,bug" ref="1361-1363">
      <para>The formatting callback has been largely rewritten for
      clarity, robustness and efficiency.</para>

      <para>If a request included a <code>Host:</code> header,
      construct and output an absolute URL.  This makes
      <code>varnishncsa</code> output from servers which handle
      multiple virtual hosts far more useful.</para>
    </change>

    <change type="bug" ref="1450">
      <para>The flag that is raised upon reception of a
      <code>SIGHUP</code> has been marked <code>volatile</code> so it
      will not be optimized away by the compiler.</para>
    </change>
  </subsystem>

  <subsystem>
    <name>Documentation</name>

    <change type="enh">
      <para>The documentation&mdash;especially the VCL
      documentation&mdash;has been greatly extended and improved.</para>
    </change>
  </subsystem>

  <subsystem>
    <name>Build system</name>

    <change type="bug" ref="1364">
      <para>The name and location of the <code>curses</code> or
      <code>ncurses</code> library is now correctly detected by the
      <code>configure</code> script instead of being hardcoded into
      affected Makefiles.  This allows Varnish to build correctly on
      a wider range of platforms.</para>
    </change>

    <change type="enh" ref="1368">
      <para>Compatibility shims for <code>clock_gettime()</code> are
      now correctly applied where needed, allowing Varnish to build
      on MacOS X.</para>
    </change>

    <change type="bug" ref="1399">
      <para>The <code>autogen.sh</code> script will now correctly
      detect and warn about <code>automake</code> versions which are
      known not to work correctly.</para>
    </change>
  </subsystem>

  <!--subsystem>
    <name>Packaging</name>

    <change type="enh">
      <para>XXX</para>
    </change>
  </subsystem-->
</group>