[OTS] Integrate WOFF 2.0 algorithm into OTS

src/ots.h

 // Copyright (c) 2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef OTS_H_
 #define OTS_H_
 
 #include <stddef.h>
 #include <cstdarg>
 #include <cstddef>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <limits>
 
 #include "opentype-sanitiser.h"
 
+// arraysize borrowed from base/basictypes.h
+template <typename T, size_t N>
+char (&ArraySizeHelper(T (&array)[N]))[N];
+#define arraysize(array) (sizeof(ArraySizeHelper(array)))
+
 namespace ots {
 
 #if defined(_MSC_VER) || !defined(OTS_DEBUG)
 #define OTS_FAILURE() false
 #else
 #define OTS_FAILURE() ots::Failure(__FILE__, __LINE__, __PRETTY_FUNCTION__)
 bool Failure(const char *f, int l, const char *fn);
 #endif
 
 #if defined(_MSC_VER)
@@ skipping 124 matching lines @@
   size_t length() const { return length_; }
 
   void set_offset(size_t newoffset) { offset_ = newoffset; }
 
  private:
   const uint8_t * const buffer_;
   const size_t length_;
   size_t offset_;
 };
 
+// Round a value up to the nearest multiple of 4. Don't round the value in the
+// case that rounding up overflows.
+template<typename T> T Round4(T value) {
+  if (std::numeric_limits<T>::max() - value < 3) {
+    return value;
+  }
+  return (value + 3) & ~3;
+}
+
+bool IsValidVersionTag(uint32_t tag);
+
 #define FOR_EACH_TABLE_TYPE \
   F(cff, CFF) \
   F(cmap, CMAP) \
   F(cvt, CVT) \
   F(fpgm, FPGM) \
   F(gasp, GASP) \
   F(gdef, GDEF) \
   F(glyf, GLYF) \
   F(gpos, GPOS) \
   F(gsub, GSUB) \
@@ skipping 41 matching lines @@
 bool ots_##name##_should_serialise(OpenTypeFile *f); \
 bool ots_##name##_serialise(OTSStream *s, OpenTypeFile *f); \
 void ots_##name##_free(OpenTypeFile *f);
 // TODO(yusukes): change these function names to follow Chromium coding rule.
 FOR_EACH_TABLE_TYPE
 #undef F
 
 }  // namespace ots
 
 #endif  // OTS_H_