current/deps/icu-small/source/common/dictionarydata.h
// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 2014, International Business Machines
* Corporation and others. All Rights Reserved.
*******************************************************************************
* dictionarydata.h
*
* created on: 2012may31
* created by: Markus W. Scherer & Maxime Serrano
*/
#ifndef __DICTIONARYDATA_H__
#define __DICTIONARYDATA_H__
#include "unicode/utypes.h"
#if !UCONFIG_NO_BREAK_ITERATION
#include "unicode/utext.h"
#include "unicode/udata.h"
#include "udataswp.h"
#include "unicode/uobject.h"
#include "unicode/ustringtrie.h"
U_NAMESPACE_BEGIN
class UCharsTrie;
class BytesTrie;
class U_COMMON_API DictionaryData : public UMemory {
public:
static const int32_t TRIE_TYPE_BYTES; // = 0;
static const int32_t TRIE_TYPE_UCHARS; // = 1;
static const int32_t TRIE_TYPE_MASK; // = 7;
static const int32_t TRIE_HAS_VALUES; // = 8;
static const int32_t TRANSFORM_NONE; // = 0;
static const int32_t TRANSFORM_TYPE_OFFSET; // = 0x1000000;
static const int32_t TRANSFORM_TYPE_MASK; // = 0x7f000000;
static const int32_t TRANSFORM_OFFSET_MASK; // = 0x1fffff;
enum {
// Byte offsets from the start of the data, after the generic header.
IX_STRING_TRIE_OFFSET,
IX_RESERVED1_OFFSET,
IX_RESERVED2_OFFSET,
IX_TOTAL_SIZE,
// Trie type: TRIE_HAS_VALUES | TRIE_TYPE_BYTES etc.
IX_TRIE_TYPE,
// Transform specification: TRANSFORM_TYPE_OFFSET | 0xe00 etc.
IX_TRANSFORM,
IX_RESERVED6,
IX_RESERVED7,
IX_COUNT
};
};
/**
* Wrapper class around generic dictionaries, implementing matches().
* getType() should return a TRIE_TYPE_??? constant from DictionaryData.
*
* All implementations of this interface must be thread-safe if they are to be used inside of the
* dictionary-based break iteration code.
*/
class U_COMMON_API DictionaryMatcher : public UMemory {
public:
DictionaryMatcher() {}
virtual ~DictionaryMatcher();
// this should emulate CompactTrieDictionary::matches()
/* @param text The text in which to look for matching words. Matching begins
* at the current position of the UText.
* @param maxLength The max length of match to consider. Units are the native indexing
* units of the UText.
* @param limit Capacity of output arrays, which is also the maximum number of
* matching words to be found.
* @param lengths output array, filled with the lengths of the matches, in order,
* from shortest to longest. Lengths are in native indexing units
* of the UText. May be NULL.
* @param cpLengths output array, filled with the lengths of the matches, in order,
* from shortest to longest. Lengths are the number of Unicode code points.
* May be NULL.
* @param values Output array, filled with the values associated with the words found.
* May be NULL.
* @param prefix Output parameter, the code point length of the prefix match, even if that
* prefix didn't lead to a complete word. Will always be >= the cpLength
* of the longest complete word matched. May be NULL.
* @return Number of matching words found.
*/
virtual int32_t matches(UText *text, int32_t maxLength, int32_t limit,
int32_t *lengths, int32_t *cpLengths, int32_t *values,
int32_t *prefix) const = 0;
/** @return DictionaryData::TRIE_TYPE_XYZ */
virtual int32_t getType() const = 0;
};
// Implementation of the DictionaryMatcher interface for a UCharsTrie dictionary
class U_COMMON_API UCharsDictionaryMatcher : public DictionaryMatcher {
public:
// constructs a new UCharsDictionaryMatcher.
// The UDataMemory * will be closed on this object's destruction.
UCharsDictionaryMatcher(const UChar *c, UDataMemory *f) : characters(c), file(f) { }
virtual ~UCharsDictionaryMatcher();
virtual int32_t matches(UText *text, int32_t maxLength, int32_t limit,
int32_t *lengths, int32_t *cpLengths, int32_t *values,
int32_t *prefix) const;
virtual int32_t getType() const;
private:
const UChar *characters;
UDataMemory *file;
};
// Implementation of the DictionaryMatcher interface for a BytesTrie dictionary
class U_COMMON_API BytesDictionaryMatcher : public DictionaryMatcher {
public:
// constructs a new BytesTrieDictionaryMatcher
// the transform constant should be the constant read from the file, not a masked version!
// the UDataMemory * fed in here will be closed on this object's destruction
BytesDictionaryMatcher(const char *c, int32_t t, UDataMemory *f)
: characters(c), transformConstant(t), file(f) { }
virtual ~BytesDictionaryMatcher();
virtual int32_t matches(UText *text, int32_t maxLength, int32_t limit,
int32_t *lengths, int32_t *cpLengths, int32_t *values,
int32_t *prefix) const;
virtual int32_t getType() const;
private:
UChar32 transform(UChar32 c) const;
const char *characters;
int32_t transformConstant;
UDataMemory *file;
};
U_NAMESPACE_END
U_CAPI int32_t U_EXPORT2
udict_swap(const UDataSwapper *ds, const void *inData, int32_t length, void *outData, UErrorCode *pErrorCode);
/**
* Format of dictionary .dict data files.
* Format version 1.0.
*
* A dictionary .dict data file contains a byte-serialized BytesTrie or
* a UChars-serialized UCharsTrie.
* Such files are used in dictionary-based break iteration (DBBI).
*
* For a BytesTrie, a transformation type is specified for
* transforming Unicode strings into byte sequences.
*
* A .dict file begins with a standard ICU data file header
* (DataHeader, see ucmndata.h and unicode/udata.h).
* The UDataInfo.dataVersion field is currently unused (set to 0.0.0.0).
*
* After the header, the file contains the following parts.
* Constants are defined in the DictionaryData class.
*
* For the data structure of BytesTrie & UCharsTrie see
* http://site.icu-project.org/design/struct/tries
* and the bytestrie.h and ucharstrie.h header files.
*
* int32_t indexes[indexesLength]; -- indexesLength=indexes[IX_STRING_TRIE_OFFSET]/4;
*
* The first four indexes are byte offsets in ascending order.
* Each byte offset marks the start of the next part in the data file,
* and the end of the previous one.
* When two consecutive byte offsets are the same, then the corresponding part is empty.
* Byte offsets are offsets from after the header,
* that is, from the beginning of the indexes[].
* Each part starts at an offset with proper alignment for its data.
* If necessary, the previous part may include padding bytes to achieve this alignment.
*
* trieType=indexes[IX_TRIE_TYPE] defines the trie type.
* transform=indexes[IX_TRANSFORM] defines the Unicode-to-bytes transformation.
* If the transformation type is TRANSFORM_TYPE_OFFSET,
* then the lower 21 bits contain the offset code point.
* Each code point c is mapped to byte b = (c - offset).
* Code points outside the range offset..(offset+0xff) cannot be mapped
* and do not occur in the dictionary.
*
* stringTrie; -- a serialized BytesTrie or UCharsTrie
*
* The dictionary maps strings to specific values (TRIE_HAS_VALUES bit set in trieType),
* or it maps all strings to 0 (TRIE_HAS_VALUES bit not set).
*/
#endif /* !UCONFIG_NO_BREAK_ITERATION */
#endif /* __DICTIONARYDATA_H__ */