Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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+# mapped_hyph
+
+mapped_hyph is a reimplementation of the hyphenation algorithm from the
+[libhyphen](https://github.com/hunspell/hyphen) library
+that is intended to reduce the in-memory footprint of loaded
+hyphenation dictionaries, especially when the same dictionary
+may be in use by multiple processes.
+
+To reduce memory footprint, mapped_hyph uses hyphenation dictionaries that are
+"precompiled" into a flat, position-independent binary format that is used
+directly by the runtime hyphenation functions.
+Therefore, dictionaries do not have to be parsed into a dynamic structure in memory;
+the files can simply be mmap'd into the address space and immediately used.
+In addition, a compiled dictionary mapped into a shared-memory block
+can be made available to multiple processes for no added physical memory cost.
+
+One deliberate simplification compared to libhyphen
+is that mapped_hyph only accepts UTF-8 text and hyphenation dictionaries;
+legacy non-Unicode encodings are not supported.
+
+mapped_hyph has been created primarily for use by Gecko, replacing the use of libhyphen,
+and so its features (and limitations) are based on this use case.
+However, it is hoped that it will also be more generally useful.
+
+## Functionality
+
+Currently, mapped_hyph supports only "standard" hyphenation, where spelling does not
+change around the hyphenation position. At present this is the only kind of
+hyphenation supported in Gecko.
+
+The compiled hyphenation dictionary format includes provision for replacement
+strings and indexes, as used by libhyphen to support non-standard hyphenations
+(e.g. German "Schiffahrt" -> "Schiff-fahrt"), but the `find_hyphen_values` function
+will ignore any such hyphenation positions it finds.
+(None of the hyphenation dictionaries shipping with Firefox includes such rules.)
+
+## Licensing
+
+mapped_hyph is dual licensed under the Apache-2.0 and MIT licenses;
+see the file COPYRIGHT.
+
+## Documentation
+
+Use `cargo doc --open` to view (admittedly brief) documentation generated from
+comments in the source.
+
+## C and C++ bindings
+
+See src/ffi.rs for C/C++ APIs that can be used to load hyphenation files
+and to locate valid hyphenation positions in a word.
+
+## Sample programs
+
+See main.rs for a simple example program.
+
+## Compiled dictionaries
+
+The `hyf_compile` tool is used to generate `.hyf` files for mapped_hyph
+from standard `.dic` (or `.pat`) files as used by libhyphen, LibreOffice, etc.
+
+(A compiled version of the `hyph_en_US` dictionary from libhyphen is currently
+included here, as it is handy for testing purposes.)
+
+## Release Notes
+
+### 0.4.0
+
+* Added a boolean `compress` param to the pattern compiler to control whether
+  it attempts to compress the compiled table by merging duplicate states (which
+  takes significant extra time).
+
+* Added FFI functions to compile hyphenation tables from a file path or a buffer,
+  intended for use from Gecko.
+
+### 0.3.0
+
+* Switched from MPL2 to Apache2/MIT dual license.
+
+* Misc bug-fixes and optimizations.
+
+### 0.2.0
+
+* Implemented a hyphenation table compiler in the `builder` submodule,
+  and `hyf_compile` command-line tool.
+
+* Moved C-callable API functions into an `ffi` submodule.
+
+### 0.1.0
+
+* Initial release.