Update to Harfbuzz 2.6.4

Quite a big change since it has been several years since
the last update. This drops the Harfbuzz source on top
of the existing code in Qt, and does the following
additional changes:

1. Deletes old source files that have been removed upstream
(everything named foo-private.hh is now renamed to just
foo.hh for instance).

2. Added a header guard to config.h because it may be
double-included.

3. Implement a memory barrier needed by hb-atomic.hh.

4. Changed the signature of hb_atomic_int_impl_add()
to take a pointer to match new upstream.

5. Updated .pro file to include new files and removed
old.

6. Updated qt_attribution.json

7. No longer disable deprecated APIs since
hb_ot_tags_from_script() is now deprecated and is used
from Qt code.

8. Updated and applied the patch in patches/ for CoreText.

9. Updated tst_qtextscriptengine::thaiWithZWJ() according to
changes in Harfbuzz and disabled it for system-harfbuzz,
since this may be an older version of harfbuzz depending on
the system.

Fixes: QTBUG-79606
Change-Id: I3f057a43ff44ee416628b75ef12fb1a221f31910
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 184 insertions, 0 deletions

diff --git a/src/3rdparty/harfbuzz-ng/src/hb-null.hh b/src/3rdparty/harfbuzz-ng/src/hb-null.hh
new file mode 100644
index 0000000000..d4578205e3
--- /dev/null
+++ b/src/3rdparty/harfbuzz-ng/src/hb-null.hh
@@ -0,0 +1,184 @@
+/*
+ * Copyright © 2018  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HB_NULL_HH
+#define HB_NULL_HH
+
+#include "hb.hh"
+#include "hb-meta.hh"
+
+
+/*
+ * Static pools
+ */
+
+/* Global nul-content Null pool.  Enlarge as necessary. */
+
+#define HB_NULL_POOL_SIZE 384
+
+/* Use SFINAE to sniff whether T has min_size; in which case return T::null_size,
+ * otherwise return sizeof(T). */
+
+/* The hard way...
+ * https://stackoverflow.com/questions/7776448/sfinae-tried-with-bool-gives-compiler-error-template-argument-tvalue-invol
+ */
+
+template <typename T, typename>
+struct _hb_null_size : hb_integral_constant<unsigned, sizeof (T)> {};
+template <typename T>
+struct _hb_null_size<T, hb_void_t<decltype (T::min_size)>> : hb_integral_constant<unsigned, T::null_size> {};
+
+template <typename T>
+using hb_null_size = _hb_null_size<T, void>;
+#define hb_null_size(T) hb_null_size<T>::value
+
+/* These doesn't belong here, but since is copy/paste from above, put it here. */
+
+/* hb_static_size (T)
+ * Returns T::static_size if T::min_size is defined, or sizeof (T) otherwise. */
+
+template <typename T, typename>
+struct _hb_static_size : hb_integral_constant<unsigned, sizeof (T)> {};
+template <typename T>
+struct _hb_static_size<T, hb_void_t<decltype (T::min_size)>> : hb_integral_constant<unsigned, T::static_size> {};
+template <typename T>
+using hb_static_size = _hb_static_size<T, void>;
+#define hb_static_size(T) hb_static_size<T>::value
+
+
+/*
+ * Null()
+ */
+
+extern HB_INTERNAL
+uint64_t const _hb_NullPool[(HB_NULL_POOL_SIZE + sizeof (uint64_t) - 1) / sizeof (uint64_t)];
+
+/* Generic nul-content Null objects. */
+template <typename Type>
+struct Null {
+  static Type const & get_null ()
+  {
+    static_assert (hb_null_size (Type) <= HB_NULL_POOL_SIZE, "Increase HB_NULL_POOL_SIZE.");
+    return *reinterpret_cast<Type const *> (_hb_NullPool);
+  }
+};
+template <typename QType>
+struct NullHelper
+{
+  typedef hb_remove_const<hb_remove_reference<QType>> Type;
+  static const Type & get_null () { return Null<Type>::get_null (); }
+};
+#define Null(Type) NullHelper<Type>::get_null ()
+
+/* Specializations for arbitrary-content Null objects expressed in bytes. */
+#define DECLARE_NULL_NAMESPACE_BYTES(Namespace, Type) \
+	} /* Close namespace. */ \
+	extern HB_INTERNAL const unsigned char _hb_Null_##Namespace##_##Type[Namespace::Type::null_size]; \
+	template <> \
+	struct Null<Namespace::Type> { \
+	  static Namespace::Type const & get_null () { \
+	    return *reinterpret_cast<const Namespace::Type *> (_hb_Null_##Namespace##_##Type); \
+	  } \
+	}; \
+	namespace Namespace { \
+	static_assert (true, "Just so we take semicolon after.")
+#define DEFINE_NULL_NAMESPACE_BYTES(Namespace, Type) \
+	const unsigned char _hb_Null_##Namespace##_##Type[Namespace::Type::null_size]
+
+/* Specializations for arbitrary-content Null objects expressed as struct initializer. */
+#define DECLARE_NULL_INSTANCE(Type) \
+	extern HB_INTERNAL const Type _hb_Null_##Type; \
+	template <> \
+	struct Null<Type> { \
+	  static Type const & get_null () { \
+	    return _hb_Null_##Type; \
+	  } \
+	}; \
+	static_assert (true, "Just so we take semicolon after.")
+#define DEFINE_NULL_INSTANCE(Type) \
+	const Type _hb_Null_##Type
+
+/* Global writable pool.  Enlarge as necessary. */
+
+/* To be fully correct, CrapPool must be thread_local. However, we do not rely on CrapPool
+ * for correct operation. It only exist to catch and divert program logic bugs instead of
+ * causing bad memory access. So, races there are not actually introducing incorrectness
+ * in the code. Has ~12kb binary size overhead to have it, also clang build fails with it. */
+extern HB_INTERNAL
+/*thread_local*/ uint64_t _hb_CrapPool[(HB_NULL_POOL_SIZE + sizeof (uint64_t) - 1) / sizeof (uint64_t)];
+
+/* CRAP pool: Common Region for Access Protection. */
+template <typename Type>
+static inline Type& Crap () {
+  static_assert (hb_null_size (Type) <= HB_NULL_POOL_SIZE, "Increase HB_NULL_POOL_SIZE.");
+  Type *obj = reinterpret_cast<Type *> (_hb_CrapPool);
+  memcpy (obj, &Null(Type), sizeof (*obj));
+  return *obj;
+}
+template <typename QType>
+struct CrapHelper
+{
+  typedef hb_remove_const<hb_remove_reference<QType>> Type;
+  static Type & get_crap () { return Crap<Type> (); }
+};
+#define Crap(Type) CrapHelper<Type>::get_crap ()
+
+template <typename Type>
+struct CrapOrNullHelper {
+  static Type & get () { return Crap(Type); }
+};
+template <typename Type>
+struct CrapOrNullHelper<const Type> {
+  static const Type & get () { return Null(Type); }
+};
+#define CrapOrNull(Type) CrapOrNullHelper<Type>::get ()
+
+
+/*
+ * hb_nonnull_ptr_t
+ */
+
+template <typename P>
+struct hb_nonnull_ptr_t
+{
+  typedef hb_remove_pointer<P> T;
+
+  hb_nonnull_ptr_t (T *v_ = nullptr) : v (v_) {}
+  T * operator = (T *v_)   { return v = v_; }
+  T * operator -> () const { return get (); }
+  T & operator * () const  { return *get (); }
+  T ** operator & () const { return &v; }
+  /* Only auto-cast to const types. */
+  template <typename C> operator const C * () const { return get (); }
+  operator const char * () const { return (const char *) get (); }
+  T * get () const { return v ? v : const_cast<T *> (&Null(T)); }
+  T * get_raw () const { return v; }
+
+  T *v;
+};
+
+
+#endif /* HB_NULL_HH */