third_party/txt/src/minikin/MinikinInternal.h

/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// Definitions internal to Minikin

#ifndef MINIKIN_INTERNAL_H
#define MINIKIN_INTERNAL_H

#include <mutex>

#include <hb.h>

#include <minikin/MinikinFont.h>

namespace minikin {

// All external Minikin interfaces are designed to be thread-safe.
// Presently, that's implemented by through a global lock, and having
// all external interfaces take that lock.

extern std::recursive_mutex gMinikinLock;

// Aborts if gMinikinLock is not acquired. Do nothing on the release build.
void assertMinikinLocked();

hb_blob_t* getFontTable(const MinikinFont* minikinFont, uint32_t tag);

constexpr uint32_t MAX_UNICODE_CODE_POINT = 0x10FFFF;

// An RAII wrapper for hb_blob_t
class HbBlob {
 public:
  // Takes ownership of hb_blob_t object, caller is no longer
  // responsible for calling hb_blob_destroy().
  explicit HbBlob(hb_blob_t* blob) : mBlob(blob) {}

  ~HbBlob() { hb_blob_destroy(mBlob); }

  const uint8_t* get() const {
    const char* data = hb_blob_get_data(mBlob, nullptr);
    return reinterpret_cast<const uint8_t*>(data);
  }

  size_t size() const { return (size_t)hb_blob_get_length(mBlob); }

 private:
  hb_blob_t* mBlob;
};

}  // namespace minikin

#endif  // MINIKIN_INTERNAL_H