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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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
#ifndef mozilla_intl_LineBreaker_h__
#define mozilla_intl_LineBreaker_h__
#include <cstdint>
#define NS_LINEBREAKER_NEED_MORE_TEXT -1
namespace mozilla {
namespace intl {
enum class LineBreakRule : uint8_t;
enum class WordBreakRule : uint8_t;
class LineBreaker final {
public:
// LineBreaker is a utility class with only static methods. No need to
// instantiate it.
LineBreaker() = delete;
~LineBreaker() = delete;
// Find the next line break opportunity starting from aPos + 1. It can return
// aLen if there's no break opportunity between [aPos + 1, aLen - 1].
//
// If aPos is already at the end of aText or beyond, i.e. aPos >= aLen, return
// NS_LINEBREAKER_NEED_MORE_TEXT.
//
// DEPRECATED: Use LineBreakIteratorUtf16 instead.
static int32_t Next(const char16_t* aText, uint32_t aLen, uint32_t aPos);
// Call this on a word with whitespace at either end. We will apply JISx4051
// rules to find breaks inside the word. aBreakBefore is set to the break-
// before status of each character; aBreakBefore[0] will always be false
// because we never return a break before the first character.
// aLength is the length of the aText array and also the length of the
// aBreakBefore output array.
static void ComputeBreakPositions(const char16_t* aText, uint32_t aLength,
WordBreakRule aWordBreak,
LineBreakRule aLevel,
bool aIsChineseOrJapanese,
uint8_t* aBreakBefore);
static void ComputeBreakPositions(const uint8_t* aText, uint32_t aLength,
WordBreakRule aWordBreak,
LineBreakRule aLevel,
bool aIsChineseOrJapanese,
uint8_t* aBreakBefore);
};
static inline bool NS_IsSpace(char16_t u) {
return u == 0x0020 || // SPACE
u == 0x0009 || // CHARACTER TABULATION
u == 0x000D || // CARRIAGE RETURN
(0x2000 <= u && u <= 0x2006) || // EN QUAD, EM QUAD, EN SPACE,
// EM SPACE, THREE-PER-EM SPACE,
// FOUR-PER-SPACE, SIX-PER-EM SPACE,
(0x2008 <= u && u <= 0x200B) || // PUNCTUATION SPACE, THIN SPACE,
// HAIR SPACE, ZERO WIDTH SPACE
u == 0x1361 || // ETHIOPIC WORDSPACE
u == 0x1680 || // OGHAM SPACE MARK
u == 0x205F; // MEDIUM MATHEMATICAL SPACE
}
static inline bool NS_NeedsPlatformNativeHandling(char16_t aChar) {
return
// Tibetan; better to just use our class-based breaker.
(0x0e01 <= aChar && aChar <= 0x0eff) || // Thai, Lao
#else
// Routing Tibetan to the platform-native breaker currently results in
// WPT failures in a few css3-text-line-break-opclns-* testcases that mix
// a Tibetan character with other-script context.
(0x0e01 <= aChar && aChar <= 0x0fff) || // Thai, Lao, Tibetan
#endif
(0x1780 <= aChar && aChar <= 0x17ff); // Khmer
}
} // namespace intl
} // namespace mozilla
#endif /* mozilla_intl_LineBreaker_h__ */