Log Message:
ghostscript-agpl: Update to 9.50

Changes:
Version 9.50 (2019-09-30)

Highlights in this release include:

  * The change to version 9.50 (rather than the intended 9.28) follows
    recognition of the extent and importance of the file access control
    redesign/reimplementation outlined below.
  * The file access control capability (enable with -dSAFER) has been
    completely rewritten, with a ground-up rethink of the design. For more
    details, see: SAFER.

    It is important to note that -dSAFER now only enables the file access
    controls, and no longer applies restrictions to standard Postscript
    functionality (specifically, restrictions on setpagedevice. If your
    application relies on these Postscript restrictions, see OLDSAFER, and
    please get in touch, as we do plan to remove those Postscript restrictions
    unless we have reason not to.

    IMPORTANT: File access controls are now enabled by default. In order to run
    Ghostscript without these controls, see NOSAFER

    Important Note for Windows Users: See below under Incompatible Changes
  * IMPORTANT: We are in the process of forking LittleCMS. LCMS2 is not thread
    safe, and cannot be made thread safe without breaking the ABI. Our fork
    will be thread safe, and include performance enhancements (these changes
    have all be been offered and rejected upstream). We will maintain
    compatibility between Ghostscript and LCMS2 for a time, but not in
    perpetuity. Our fork will be available as its own package separately from
    Ghostscript (and MuPDF).
  * The usual round of bug fixes, compatibility changes, and incremental
    improvements.
  * Special thanks to Akira Kakuto, Paul Wessel, William Bader, Nelson H. F.
    Beebe and everyone else who put time and effort into testing this new
    release.

For a list of open issues, or to report problems, please visit
bugs.ghostscript.com.

Incompatible changes

  * There are a couple of subtle incompatibilities between the old and new
    SAFER implementations. Firstly, as mentioned above, SAFER now leaves
    standard Postcript functionality unchanged (except for the file access
    limitations). Secondly, the interaction with save/restore operations,
    see SAFER.

    Important Note for Windows Users:
    The file/path pattern matching is case sensitive, even on Windows. This is
    a change in behaviour compared to the old code which, on Windows, was case
    insensitive. This is in recognition of changes in Windows behaviour, in
    that it now supports (although does not enforce) case sensitivity.
  * The following is not strictly speaking new to 9.50, as not much has changed
    since 9.27 in this area, but for those who don't upgrade with every
    release:

    The process of "tidying" the Postscript name space should have \ 
removed only
    non-standard and undocumented operators. Nevertheless, it is possible that
    any integrations or utilities that rely on those non-standard and
    undocumented operators may stop working, or may change behaviour.

    If you encounter such a case, please contact us (either the #ghostscript
    IRC channel, or the gs-devel mailing list would be best), and we'll work
    with you to either find an alternative solution or return the previous
    functionality, if there is genuinely no other option.

    One case we know this has occurred is GSView 5 (and earlier). GSView 5
    support for PDF files relied upon internal use only features which are no
    longer available. GSView 5 will still work as previously for Postscript
    files. For PDF files, users are encouraged to look at MuPDF.