k2pdfopt: fix build against mupdf >= 1.25.0 (#397905)

  runCommand,

  fetchzip,

  fetchurl,

  fetchpatch,

  fetchFromGitHub,

  cmake,

  jbig2dec,

          cp ${k2pdfopt_src}/mupdf_mod/pdf-* ./source/pdf/

        '';

      };

      # mupdf_patch no longer applies cleanly against mupdf 1.25.0 or later, due to a conflicting

      # hunk (mupdf_conflict) introduced in commit bd8d337939f36f55b96cb6984f5c7bbf2f488ce0 of mupdf.

      # This merge conflict can be resolved as desired by reverting mupdf_conflict, applying mupdf_patch,

      # and finally reapplying mupdf_conflict, with an increased fuzz factor (see mupdf_modded below).

      # TODO: remove workaround with conflicting hunk when mupdf in k2pdfopt is updated to 1.25.0 or later

      mupdf_conflict =

        hash: revert:

        fetchpatch {

          name = "mupdf-conflicting-hunk" + (lib.optionalString revert "-reverted") + ".patch";

          url = "https://github.com/ArtifexSoftware/mupdf/commit/bd8d337939f36f55b96cb6984f5c7bbf2f488ce0.patch";

          inherit hash revert;

          includes = [ "source/fitz/stext-device.c" ];

          postFetch = ''

            filterdiff -#6 "$out" > "$tmpfile"

            mv "$tmpfile" "$out"

          '';

        };

      mupdf_modded = mupdf.overrideAttrs (

        {

          patches ? [ ],

          ...

        }:

        {

          patches = patches ++ [ mupdf_patch ];

          # The fuzz factor is increased to automatically resolve the merge conflict.

          patchFlags = [

            "-p1"

            "-F3"

          ];

          # Reverting and reapplying the conflicting hunk is necessary, otherwise the result will be faulty.

          patches = patches ++ [

            # revert conflicting hunk

            (mupdf_conflict "sha256-24tl9YBuZBYhb12yY3T0lKsA7NswfK0QcMYhb2IpepA=" true)

            # apply modifications

            mupdf_patch

            # reapply conflicting hunk

            (mupdf_conflict "sha256-bnBV7LyX1w/BXxBFF1bkA8x+/0I9Am33o8GiAeEKHYQ=" false)

          ];

          # This function is missing in font.c, see font-win32.c

          postPatch = ''

            echo "void pdf_install_load_system_font_funcs(fz_context *ctx) {}" >> source/fitz/font.c