diff options
Diffstat (limited to 'thirdparty/harfbuzz/src/hb-serialize.hh')
| -rw-r--r-- | thirdparty/harfbuzz/src/hb-serialize.hh | 62 |
1 files changed, 52 insertions, 10 deletions
diff --git a/thirdparty/harfbuzz/src/hb-serialize.hh b/thirdparty/harfbuzz/src/hb-serialize.hh index 7212d9872a..57689916f6 100644 --- a/thirdparty/harfbuzz/src/hb-serialize.hh +++ b/thirdparty/harfbuzz/src/hb-serialize.hh @@ -189,8 +189,8 @@ struct hb_serialize_context_t { return check_success (!hb_deref (obj).in_error ()); } template <typename T1, typename... Ts> bool propagate_error (T1 &&o1, Ts&&... os) - { return propagate_error (hb_forward<T1> (o1)) && - propagate_error (hb_forward<Ts> (os)...); } + { return propagate_error (std::forward<T1> (o1)) && + propagate_error (std::forward<Ts> (os)...); } /* To be called around main operation. */ template <typename Type> @@ -358,6 +358,35 @@ struct hb_serialize_context_t assert (packed.tail ()->head == tail); } + // Adds a virtual link from the current object to objidx. A virtual link is not associated with + // an actual offset field. They are solely used to enforce ordering constraints between objects. + // Adding a virtual link from object a to object b will ensure that object b is always packed after + // object a in the final serialized order. + // + // This is useful in certain situtations where there needs to be a specific ordering in the + // final serialization. Such as when platform bugs require certain orderings, or to provide + // guidance to the repacker for better offset overflow resolution. + void add_virtual_link (objidx_t objidx) + { + if (unlikely (in_error ())) return; + + if (!objidx) + return; + + assert (current); + + auto& link = *current->links.push (); + if (current->links.in_error ()) + err (HB_SERIALIZE_ERROR_OTHER); + + link.width = 0; + link.objidx = objidx; + link.is_signed = 0; + link.whence = 0; + link.position = 0; + link.bias = 0; + } + template <typename T> void add_link (T &ofs, objidx_t objidx, whence_t whence = Head, @@ -376,11 +405,22 @@ struct hb_serialize_context_t err (HB_SERIALIZE_ERROR_OTHER); link.width = sizeof (T); - link.is_signed = hb_is_signed (hb_unwrap_type (T)); + link.objidx = objidx; + if (unlikely (!sizeof (T))) + { + // This link is not associated with an actual offset and exists merely to enforce + // an ordering constraint. + link.is_signed = 0; + link.whence = 0; + link.position = 0; + link.bias = 0; + return; + } + + link.is_signed = std::is_signed<hb_unwrap_type (T)>::value; link.whence = (unsigned) whence; link.position = (const char *) &ofs - current->head; link.bias = bias; - link.objidx = objidx; } unsigned to_bias (const void *base) const @@ -402,6 +442,8 @@ struct hb_serialize_context_t for (const object_t* parent : ++hb_iter (packed)) for (const object_t::link_t &link : parent->links) { + if (unlikely (!link.width)) continue; // Don't need to resolve virtual offsets + const object_t* child = packed[link.objidx]; if (unlikely (!child)) { err (HB_SERIALIZE_ERROR_OTHER); return; } unsigned offset = 0; @@ -494,7 +536,7 @@ struct hb_serialize_context_t template <typename Type, typename ...Ts> auto _copy (const Type &src, hb_priority<1>, Ts&&... ds) HB_RETURN - (Type *, src.copy (this, hb_forward<Ts> (ds)...)) + (Type *, src.copy (this, std::forward<Ts> (ds)...)) template <typename Type> auto _copy (const Type &src, hb_priority<0>) -> decltype (&(hb_declval<Type> () = src)) @@ -509,16 +551,16 @@ struct hb_serialize_context_t * instead of memcpy(). */ template <typename Type, typename ...Ts> Type *copy (const Type &src, Ts&&... ds) - { return _copy (src, hb_prioritize, hb_forward<Ts> (ds)...); } + { return _copy (src, hb_prioritize, std::forward<Ts> (ds)...); } template <typename Type, typename ...Ts> Type *copy (const Type *src, Ts&&... ds) - { return copy (*src, hb_forward<Ts> (ds)...); } + { return copy (*src, std::forward<Ts> (ds)...); } template<typename Iterator, hb_requires (hb_is_iterator (Iterator)), typename ...Ts> void copy_all (Iterator it, Ts&&... ds) - { for (decltype (*it) _ : it) copy (_, hb_forward<Ts> (ds)...); } + { for (decltype (*it) _ : it) copy (_, std::forward<Ts> (ds)...); } template <typename Type> hb_serialize_context_t& operator << (const Type &obj) & { embed (obj); return *this; } @@ -546,10 +588,10 @@ struct hb_serialize_context_t template <typename Type, typename ...Ts> Type *extend (Type *obj, Ts&&... ds) - { return extend_size (obj, obj->get_size (hb_forward<Ts> (ds)...)); } + { return extend_size (obj, obj->get_size (std::forward<Ts> (ds)...)); } template <typename Type, typename ...Ts> Type *extend (Type &obj, Ts&&... ds) - { return extend (hb_addressof (obj), hb_forward<Ts> (ds)...); } + { return extend (hb_addressof (obj), std::forward<Ts> (ds)...); } /* Output routines. */ hb_bytes_t copy_bytes () const |