From 88a41472404a8e7754e1099ca4a5b2146dae5298 Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Thu, 2 May 2019 14:22:31 -0700
Subject: [PATCH] [serializer] Accept exact type in serialize_subset/copy()

---
 src/hb-open-type.hh            | 12 ++++++------
 src/hb-ot-layout-common.hh     | 33 ++-------------------------------
 src/hb-ot-layout-gpos-table.hh |  6 ++++++
 src/hb-ot-layout-gsub-table.hh |  6 ++++++
 4 files changed, 20 insertions(+), 37 deletions(-)

diff --git a/src/hb-open-type.hh b/src/hb-open-type.hh
index cd80b3a..808e182 100644
--- a/src/hb-open-type.hh
+++ b/src/hb-open-type.hh
@@ -284,11 +284,11 @@ struct OffsetTo : Offset<OffsetType, has_null>
     return * (Type *) Offset<OffsetType>::serialize (c, base);
   }
 
-  template <typename T, typename ...Ts>
-  bool serialize_subset (hb_subset_context_t *c, const T &src, const void *base, Ts &&...ds)
+  template <typename ...Ts>
+  bool serialize_subset (hb_subset_context_t *c, const Type &src, const void *base, Ts &&...ds)
   {
     *this = 0;
-    if (has_null && &src == &Null (T))
+    if (has_null && &src == &Null (Type))
       return false;
 
     auto *s = c->serializer;
@@ -305,11 +305,11 @@ struct OffsetTo : Offset<OffsetType, has_null>
     return ret;
   }
 
-  template <typename T, typename ...Ts>
-  bool serialize_copy (hb_serialize_context_t *c, const T &src, const void *base, Ts &&...ds)
+  template <typename ...Ts>
+  bool serialize_copy (hb_serialize_context_t *c, const Type &src, const void *base, Ts &&...ds)
   {
     *this = 0;
-    if (has_null && &src == &Null (T))
+    if (has_null && &src == &Null (Type))
       return false;
 
     c->push ();
diff --git a/src/hb-ot-layout-common.hh b/src/hb-ot-layout-common.hh
index c8dcc32..3089801 100644
--- a/src/hb-ot-layout-common.hh
+++ b/src/hb-ot-layout-common.hh
@@ -715,23 +715,6 @@ struct Lookup
     return_trace (true);
   }
 
-  /* Older compilers need this to NOT be locally defined in a function. */
-  template <typename TSubTable>
-  struct SubTableSubsetWrapper
-  {
-    SubTableSubsetWrapper (const TSubTable &subtable_,
-			   unsigned int lookup_type_) :
-			     subtable (subtable_),
-			     lookup_type (lookup_type_) {}
-
-    bool subset (hb_subset_context_t *c) const
-    { return subtable.dispatch (c, lookup_type); }
-
-    private:
-    const TSubTable &subtable;
-    unsigned int lookup_type;
-  };
-
   template <typename TSubTable>
   bool subset (hb_subset_context_t *c) const
   {
@@ -746,23 +729,11 @@ struct Lookup
     OffsetArrayOf<TSubTable>& out_subtables = out->get_subtables<TSubTable> ();
     unsigned int count = subTable.len;
     for (unsigned int i = 0; i < count; i++)
-    {
-      SubTableSubsetWrapper<TSubTable> wrapper (this+subtables[i], get_type ());
-
-      out_subtables[i].serialize_subset (c, wrapper, out);
-    }
+      out_subtables[i].serialize_subset (c, this+subtables[i], out, get_type ());
 
     return_trace (true);
   }
 
-  /* Older compilers need this to NOT be locally defined in a function. */
-  template <typename TSubTable>
-  struct SubTableSanitizeWrapper : TSubTable
-  {
-    bool sanitize (hb_sanitize_context_t *c, unsigned int lookup_type) const
-    { return this->dispatch (c, lookup_type); }
-  };
-
   template <typename TSubTable>
   bool sanitize (hb_sanitize_context_t *c) const
   {
@@ -774,7 +745,7 @@ struct Lookup
       if (!markFilteringSet.sanitize (c)) return_trace (false);
     }
 
-    if (unlikely (!CastR<OffsetArrayOf<SubTableSanitizeWrapper<TSubTable>>> (subTable)
+    if (unlikely (!CastR<OffsetArrayOf<TSubTable>> (subTable)
 		   .sanitize (c, this, get_type ())))
       return_trace (false);
 
diff --git a/src/hb-ot-layout-gpos-table.hh b/src/hb-ot-layout-gpos-table.hh
index 407ce9e..4b752fc 100644
--- a/src/hb-ot-layout-gpos-table.hh
+++ b/src/hb-ot-layout-gpos-table.hh
@@ -1525,6 +1525,12 @@ struct PosLookupSubTable
     }
   }
 
+  /* XXX Remove? */
+  bool subset (hb_subset_context_t *c, unsigned lookup_type) const
+  { return dispatch (c, lookup_type); }
+  bool sanitize (hb_sanitize_context_t *c, unsigned lookup_type) const
+  { return dispatch (c, lookup_type); }
+
   protected:
   union {
   SinglePos		single;
diff --git a/src/hb-ot-layout-gsub-table.hh b/src/hb-ot-layout-gsub-table.hh
index be78c1a..4a6f48f 100644
--- a/src/hb-ot-layout-gsub-table.hh
+++ b/src/hb-ot-layout-gsub-table.hh
@@ -1170,6 +1170,12 @@ struct SubstLookupSubTable
     }
   }
 
+  /* XXX Remove? */
+  bool subset (hb_subset_context_t *c, unsigned lookup_type) const
+  { return dispatch (c, lookup_type); }
+  bool sanitize (hb_sanitize_context_t *c, unsigned lookup_type) const
+  { return dispatch (c, lookup_type); }
+
   protected:
   union {
   SingleSubst			single;
-- 
2.7.4