layout/generic/RubyUtils.h
author Nika Layzell <nika@thelayzells.com>
Tue, 25 Sep 2018 17:34:53 +0200
changeset 507828 5e6dae0c1e5a4939ccd406f14607f7fafffd45a7
parent 489419 73c353f1d88fd07830c9034ad67800f333149cee
child 508163 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1448426 - Wrap windows.h to avoid problematic define statements, r=froydnj,glandium By default, windows.h exposes a large number of problematic define statements which are UpperCamelCase, such as a define from `CreateWindow` to `CreateWindow{A,W}`. As many of these names are generic (e.g. CreateFile, CreateWindow), they can mess up Gecko code that may legitimately have its own methods with the same names. The header also defines some traditional SCREAMING_SNAKE_CASE defines which can mess up our code by conflicting with local values. This patch adds a simple code generator which generates wrappers for these defines, and uses them to wrap the windows.h wrapper using the `stl_wrappers` mechanism, allowing us to use windows.h in more places. Differential Revision: https://phabricator.services.mozilla.com/D10932

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_RubyUtils_h_
#define mozilla_RubyUtils_h_

#include "nsCSSAnonBoxes.h"
#include "nsGkAtoms.h"
#include "nsIFrame.h"
#include "nsTArray.h"

#define RTC_ARRAY_SIZE 1

class nsRubyFrame;
class nsRubyBaseFrame;
class nsRubyTextFrame;
class nsRubyContentFrame;
class nsRubyBaseContainerFrame;
class nsRubyTextContainerFrame;

namespace mozilla {

/**
 * Reserved ISize
 *
 * With some exceptions, each ruby internal box has two isizes, which
 * are the reflowed isize and the final isize. The reflowed isize is
 * what a box itself needs. It is determined when the box gets reflowed.
 *
 * The final isize is what a box should be as the final result. For a
 * ruby base/text box, the final isize is the size of its ruby column.
 * For a ruby base/text container, the final isize is the size of its
 * ruby segment. The final isize is never smaller than the reflowed
 * isize. It is initially determined when a ruby column/segment gets
 * fully reflowed, and may be advanced when a box is expanded, e.g.
 * for justification.
 *
 * The difference between the reflowed isize and the final isize is
 * reserved in the line layout after reflowing a box, hence it is called
 * "Reserved ISize" here. It is used to expand the ruby boxes from their
 * reflowed isize to the final isize during alignment of the line.
 *
 * There are three exceptions for the final isize:
 * 1. A ruby text container has a larger final isize only if it is for
 *    a span or collapsed annotations.
 * 2. A ruby base container has a larger final isize only if at least
 *    one of its ruby text containers does.
 * 3. If a ruby text container has a larger final isize, its children
 *    must not have.
 */

class RubyUtils
{
public:
  static inline bool IsRubyContentBox(LayoutFrameType aFrameType)
  {
    return aFrameType == mozilla::LayoutFrameType::RubyBase ||
           aFrameType == mozilla::LayoutFrameType::RubyText;
  }

  static inline bool IsRubyContainerBox(LayoutFrameType aFrameType)
  {
    return aFrameType == mozilla::LayoutFrameType::RubyBaseContainer ||
           aFrameType == mozilla::LayoutFrameType::RubyTextContainer;
  }

  static inline bool IsRubyBox(LayoutFrameType aFrameType)
  {
    return aFrameType == mozilla::LayoutFrameType::Ruby ||
           IsRubyContentBox(aFrameType) || IsRubyContainerBox(aFrameType);
  }

  static inline bool IsExpandableRubyBox(nsIFrame* aFrame)
  {
    mozilla::LayoutFrameType type = aFrame->Type();
    return IsRubyContentBox(type) || IsRubyContainerBox(type);
  }

  static inline bool IsRubyPseudo(nsAtom* aPseudo)
  {
    return aPseudo == nsCSSAnonBoxes::ruby() ||
           aPseudo == nsCSSAnonBoxes::rubyBase() ||
           aPseudo == nsCSSAnonBoxes::rubyText() ||
           aPseudo == nsCSSAnonBoxes::rubyBaseContainer() ||
           aPseudo == nsCSSAnonBoxes::rubyTextContainer();
  }

  static void SetReservedISize(nsIFrame* aFrame, nscoord aISize);
  static void ClearReservedISize(nsIFrame* aFrame);
  static nscoord GetReservedISize(nsIFrame* aFrame);
};

/**
 * This array stores all ruby text containers of the ruby segment
 * of the given ruby base container.
 */
class MOZ_RAII AutoRubyTextContainerArray final
  : public AutoTArray<nsRubyTextContainerFrame*, RTC_ARRAY_SIZE>
{
public:
  explicit AutoRubyTextContainerArray(nsRubyBaseContainerFrame* aBaseContainer);
};

/**
 * This enumerator enumerates each ruby segment.
 */
class MOZ_STACK_CLASS RubySegmentEnumerator
{
public:
  explicit RubySegmentEnumerator(nsRubyFrame* aRubyFrame);

  void Next();
  bool AtEnd() const { return !mBaseContainer; }

  nsRubyBaseContainerFrame* GetBaseContainer() const
  {
    return mBaseContainer;
  }

private:
  nsRubyBaseContainerFrame* mBaseContainer;
};

/**
 * Ruby column is a unit consists of one ruby base and all ruby
 * annotations paired with it.
 * See http://dev.w3.org/csswg/css-ruby/#ruby-pairing
 */
struct MOZ_STACK_CLASS RubyColumn
{
  nsRubyBaseFrame* mBaseFrame;
  AutoTArray<nsRubyTextFrame*, RTC_ARRAY_SIZE> mTextFrames;
  bool mIsIntraLevelWhitespace;

  RubyColumn() : mBaseFrame(nullptr), mIsIntraLevelWhitespace(false) { }

  // Helper class to support iteration across the frames within a single
  // RubyColumn (the column's ruby base and its annotations).
  class MOZ_STACK_CLASS Iterator
  {
  public:
    nsIFrame* operator*() const;

    Iterator& operator++() { ++mIndex; SkipUntilExistingFrame(); return *this; }
    Iterator operator++(int) { auto ret = *this; ++*this; return ret; }

    friend bool operator==(const Iterator& aIter1, const Iterator& aIter2)
    {
      MOZ_ASSERT(&aIter1.mColumn == &aIter2.mColumn,
                 "Should only compare iterators of the same ruby column");
      return aIter1.mIndex == aIter2.mIndex;
    }
    friend bool operator!=(const Iterator& aIter1, const Iterator& aIter2)
    {
      return !(aIter1 == aIter2);
    }

  private:
    Iterator(const RubyColumn& aColumn, int32_t aIndex)
      : mColumn(aColumn)
      , mIndex(aIndex)
    {
      MOZ_ASSERT(aIndex == -1 ||
                 (aIndex >= 0 &&
                  aIndex <= int32_t(aColumn.mTextFrames.Length())));
      SkipUntilExistingFrame();
    }
    friend struct RubyColumn; // for the constructor

    void SkipUntilExistingFrame();

    const RubyColumn& mColumn;
    // -1 means the ruby base frame,
    // non-negative means the index of ruby text frame
    // a value of mTextFrames.Length() means we're done iterating
    int32_t mIndex = -1;
  };

  Iterator begin() const { return Iterator(*this, -1); }
  Iterator end() const { return Iterator(*this, mTextFrames.Length()); }
  Iterator cbegin() const { return begin(); }
  Iterator cend() const { return end(); }
};

/**
 * This enumerator enumerates ruby columns in a segment.
 */
class MOZ_STACK_CLASS RubyColumnEnumerator
{
public:
  RubyColumnEnumerator(nsRubyBaseContainerFrame* aRBCFrame,
                       const AutoRubyTextContainerArray& aRTCFrames);

  void Next();
  bool AtEnd() const;

  uint32_t GetLevelCount() const { return mFrames.Length(); }
  nsRubyContentFrame* GetFrameAtLevel(uint32_t aIndex) const;
  void GetColumn(RubyColumn& aColumn) const;

private:
  // Frames in this array are NOT necessary part of the current column.
  // When in doubt, use GetFrameAtLevel to access it.
  // See GetFrameAtLevel() and Next() for more info.
  AutoTArray<nsRubyContentFrame*, RTC_ARRAY_SIZE + 1> mFrames;
  // Whether we are on a column for intra-level whitespaces
  bool mAtIntraLevelWhitespace;
};

/**
 * Stores block-axis leadings produced from ruby annotations.
 */
struct RubyBlockLeadings
{
  nscoord mStart = 0;
  nscoord mEnd = 0;

  void Reset() {
    mStart = mEnd = 0;
  }
  void Update(nscoord aStart, nscoord aEnd) {
    mStart = std::max(mStart, aStart);
    mEnd = std::max(mEnd, aEnd);
  }
  void Update(const RubyBlockLeadings& aOther) {
    Update(aOther.mStart, aOther.mEnd);
  }
};

} // namespace mozilla

#endif /* !defined(mozilla_RubyUtils_h_) */