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+ftfuzzer
+========
+
+
+ftfuzzer.cc
+-----------
+
+This file contains a target function for FreeType fuzzing. It can be
+used with libFuzzer (https://llvm.org/docs/LibFuzzer.html) or
+potentially any other similar fuzzer.
+
+Usage:
+
+ 1. Build `libfreetype.a' and `ftfuzzer.cc' using the most recent
+ clang compiler with these flags:
+
+ # for fuzzer coverage feedback
+ -fsanitize-coverage=edge,8bit-counters
+ # for bug checking
+ -fsanitize=address,signed-integer-overflow,shift
+
+ You also need the header files from the `libarchive' library
+ (https://www.libarchive.org/) for handling tar files (see file
+ `ftmutator.cc' below for more).
+
+ 2. Link with `libFuzzer' (it contains `main') and `libarchive'.
+
+ 3. Run the fuzzer on some test corpus.
+
+The exact flags and commands may vary.
+
+ https://github.com/google/oss-fuzz/tree/master/projects/freetype2
+
+There is a continuous fuzzing bot that runs ftfuzzer.
+
+ https://oss-fuzz.com
+
+(You need an account to be able to see coverage reports and the like
+on oss-fuzz.com.)
+
+Check the bot configuration for the most current settings.
+
+
+ftmutator.cc
+------------
+
+FreeType has the ability to `attach' auxiliary files to a font file,
+providing additional information. The main usage is to load AFM files
+for PostScript Type 1 fonts.
+
+However, libFuzzer currently only supports mutation of a single input
+file. For this reason, `ftmutator.cc' contains a custom fuzzer
+mutator that uses an uncompressed tar file archive as the input. The
+first file in such a tarball gets opened by FreeType as a font, all
+other files are treated as input for `FT_Attach_Stream'.
+
+Compilation is similar to `ftfuzzer.c'.
+
+
+runinput.cc
+-----------
+
+To run the target function on a set of input files, this file contains
+a convenience `main' function. Link it with `ftfuzzer.cc',
+`libfreetype.a', and `libarchive' and run like
+
+ ./a.out my_tests_inputs/*
+
+----------------------------------------------------------------------
+
+Copyright 2015-2018 by
+David Turner, Robert Wilhelm, and Werner Lemberg.
+
+This file is part of the FreeType project, and may only be used,
+modified, and distributed under the terms of the FreeType project
+license, LICENSE.TXT. By continuing to use, modify, or distribute
+this file you indicate that you have read the license and understand
+and accept it fully.
+
+
+--- end of README ---