android / platform / external / icu4c / e4bd30ae28bdb65c480411b345a41373ae899852 / . / i18n / collationweights.h

/* | |

******************************************************************************* | |

* | |

* Copyright (C) 1999-2014, International Business Machines | |

* Corporation and others. All Rights Reserved. | |

* | |

******************************************************************************* | |

* file name: collationweights.h | |

* encoding: US-ASCII | |

* tab size: 8 (not used) | |

* indentation:4 | |

* | |

* created on: 2001mar08 as ucol_wgt.h | |

* created by: Markus W. Scherer | |

*/ | |

#ifndef __COLLATIONWEIGHTS_H__ | |

#define __COLLATIONWEIGHTS_H__ | |

#include "unicode/utypes.h" | |

#if !UCONFIG_NO_COLLATION | |

#include "unicode/uobject.h" | |

U_NAMESPACE_BEGIN | |

/** | |

* Allocates n collation element weights between two exclusive limits. | |

* Used only internally by the collation tailoring builder. | |

*/ | |

class U_I18N_API CollationWeights : public UMemory { | |

public: | |

CollationWeights(); | |

static inline int32_t lengthOfWeight(uint32_t weight) { | |

if((weight&0xffffff)==0) { | |

return 1; | |

} else if((weight&0xffff)==0) { | |

return 2; | |

} else if((weight&0xff)==0) { | |

return 3; | |

} else { | |

return 4; | |

} | |

} | |

void initForPrimary(UBool compressible); | |

void initForSecondary(); | |

void initForTertiary(); | |

/** | |

* Determine heuristically | |

* what ranges to use for a given number of weights between (excluding) | |

* two limits. | |

* | |

* @param lowerLimit A collation element weight; the ranges will be filled to cover | |

* weights greater than this one. | |

* @param upperLimit A collation element weight; the ranges will be filled to cover | |

* weights less than this one. | |

* @param n The number of collation element weights w necessary such that | |

* lowerLimit<w<upperLimit in lexical order. | |

* @return TRUE if it is possible to fit n elements between the limits | |

*/ | |

UBool allocWeights(uint32_t lowerLimit, uint32_t upperLimit, int32_t n); | |

/** | |

* Given a set of ranges calculated by allocWeights(), | |

* iterate through the weights. | |

* The ranges are modified to keep the current iteration state. | |

* | |

* @return The next weight in the ranges, or 0xffffffff if there is none left. | |

*/ | |

uint32_t nextWeight(); | |

/** @internal */ | |

struct WeightRange { | |

uint32_t start, end; | |

int32_t length, count; | |

}; | |

private: | |

/** @return number of usable byte values for byte idx */ | |

inline int32_t countBytes(int32_t idx) const { | |

return (int32_t)(maxBytes[idx] - minBytes[idx] + 1); | |

} | |

uint32_t incWeight(uint32_t weight, int32_t length) const; | |

uint32_t incWeightByOffset(uint32_t weight, int32_t length, int32_t offset) const; | |

void lengthenRange(WeightRange &range) const; | |

/** | |

* Takes two CE weights and calculates the | |

* possible ranges of weights between the two limits, excluding them. | |

* For weights with up to 4 bytes there are up to 2*4-1=7 ranges. | |

*/ | |

UBool getWeightRanges(uint32_t lowerLimit, uint32_t upperLimit); | |

UBool allocWeightsInShortRanges(int32_t n, int32_t minLength); | |

UBool allocWeightsInMinLengthRanges(int32_t n, int32_t minLength); | |

int32_t middleLength; | |

uint32_t minBytes[5]; // for byte 1, 2, 3, 4 | |

uint32_t maxBytes[5]; | |

WeightRange ranges[7]; | |

int32_t rangeIndex; | |

int32_t rangeCount; | |

}; | |

U_NAMESPACE_END | |

#endif // !UCONFIG_NO_COLLATION | |

#endif // __COLLATIONWEIGHTS_H__ |