1 /*
2 *******************************************************************************
3 *
4 * Copyright (C) 2001-2010, International Business Machines
5 * Corporation and others. All Rights Reserved.
6 *
7 *******************************************************************************
8 * file name: casetrn.cpp
9 * encoding: US-ASCII
10 * tab size: 8 (not used)
11 * indentation:4
12 *
13 * created on: 2004sep03
14 * created by: Markus W. Scherer
15 *
16 * Implementation class for lower-/upper-/title-casing transliterators.
17 */
18
19 #include "unicode/utypes.h"
20
21 #if !UCONFIG_NO_TRANSLITERATION
22
23 #include "unicode/uchar.h"
24 #include "unicode/ustring.h"
25 #include "tolowtrn.h"
26 #include "ucase.h"
27 #include "cpputils.h"
28
29 /* case context iterator using a Replaceable */
30 U_CFUNC UChar32 U_CALLCONV
utrans_rep_caseContextIterator(void * context,int8_t dir)31 utrans_rep_caseContextIterator(void *context, int8_t dir)
32 {
33 U_NAMESPACE_USE
34
35 UCaseContext *csc=(UCaseContext *)context;
36 Replaceable *rep=(Replaceable *)csc->p;
37 UChar32 c;
38
39 if(dir<0) {
40 /* reset for backward iteration */
41 csc->index=csc->cpStart;
42 csc->dir=dir;
43 } else if(dir>0) {
44 /* reset for forward iteration */
45 csc->index=csc->cpLimit;
46 csc->dir=dir;
47 } else {
48 /* continue current iteration direction */
49 dir=csc->dir;
50 }
51
52 // automatically adjust start and limit if the Replaceable disagrees
53 // with the original values
54 if(dir<0) {
55 if(csc->start<csc->index) {
56 c=rep->char32At(csc->index-1);
57 if(c<0) {
58 csc->start=csc->index;
59 } else {
60 csc->index-=U16_LENGTH(c);
61 return c;
62 }
63 }
64 } else {
65 // detect, and store in csc->b1, if we hit the limit
66 if(csc->index<csc->limit) {
67 c=rep->char32At(csc->index);
68 if(c<0) {
69 csc->limit=csc->index;
70 csc->b1=TRUE;
71 } else {
72 csc->index+=U16_LENGTH(c);
73 return c;
74 }
75 } else {
76 csc->b1=TRUE;
77 }
78 }
79 return U_SENTINEL;
80 }
81
82 U_NAMESPACE_BEGIN
83
UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(CaseMapTransliterator)84 UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(CaseMapTransliterator)
85
86 /**
87 * Constructs a transliterator.
88 */
89 CaseMapTransliterator::CaseMapTransliterator(const UnicodeString &id, UCaseMapFull *map) :
90 Transliterator(id, 0),
91 fCsp(ucase_getSingleton()),
92 fMap(map)
93 {
94 // TODO test incremental mode with context-sensitive text (e.g. greek sigma)
95 // TODO need to call setMaximumContextLength()?!
96 }
97
98 /**
99 * Destructor.
100 */
~CaseMapTransliterator()101 CaseMapTransliterator::~CaseMapTransliterator() {
102 }
103
104 /**
105 * Copy constructor.
106 */
CaseMapTransliterator(const CaseMapTransliterator & o)107 CaseMapTransliterator::CaseMapTransliterator(const CaseMapTransliterator& o) :
108 Transliterator(o),
109 fCsp(o.fCsp), fMap(o.fMap)
110 {
111 }
112
113 /**
114 * Assignment operator.
115 */
116 /*CaseMapTransliterator& CaseMapTransliterator::operator=(const CaseMapTransliterator& o) {
117 Transliterator::operator=(o);
118 fCsp = o.fCsp;
119 fMap = o.fMap;
120 return *this;
121 }*/
122
123 /**
124 * Transliterator API.
125 */
126 /*Transliterator* CaseMapTransliterator::clone(void) const {
127 return new CaseMapTransliterator(*this);
128 }*/
129
130 /**
131 * Implements {@link Transliterator#handleTransliterate}.
132 */
handleTransliterate(Replaceable & text,UTransPosition & offsets,UBool isIncremental) const133 void CaseMapTransliterator::handleTransliterate(Replaceable& text,
134 UTransPosition& offsets,
135 UBool isIncremental) const
136 {
137 if (offsets.start >= offsets.limit) {
138 return;
139 }
140
141 UCaseContext csc;
142 uprv_memset(&csc, 0, sizeof(csc));
143 csc.p = &text;
144 csc.start = offsets.contextStart;
145 csc.limit = offsets.contextLimit;
146
147 UnicodeString tmp;
148 const UChar *s;
149 UChar32 c;
150 int32_t textPos, delta, result, locCache=0;
151
152 for(textPos=offsets.start; textPos<offsets.limit;) {
153 csc.cpStart=textPos;
154 c=text.char32At(textPos);
155 csc.cpLimit=textPos+=U16_LENGTH(c);
156
157 result=fMap(fCsp, c, utrans_rep_caseContextIterator, &csc, &s, "", &locCache);
158
159 if(csc.b1 && isIncremental) {
160 // fMap() tried to look beyond the context limit
161 // wait for more input
162 offsets.start=csc.cpStart;
163 return;
164 }
165
166 if(result>=0) {
167 // replace the current code point with its full case mapping result
168 // see UCASE_MAX_STRING_LENGTH
169 if(result<=UCASE_MAX_STRING_LENGTH) {
170 // string s[result]
171 tmp.setTo(FALSE, s, result);
172 delta=result-U16_LENGTH(c);
173 } else {
174 // single code point
175 tmp.setTo(result);
176 delta=tmp.length()-U16_LENGTH(c);
177 }
178 text.handleReplaceBetween(csc.cpStart, textPos, tmp);
179 if(delta!=0) {
180 textPos+=delta;
181 csc.limit=offsets.contextLimit+=delta;
182 offsets.limit+=delta;
183 }
184 }
185 }
186 offsets.start=textPos;
187 }
188
189 U_NAMESPACE_END
190
191 #endif /* #if !UCONFIG_NO_TRANSLITERATION */
192