Check in the pristine copy of ICU 4.6...

icu46/source/i18n/casetrn.cpp

+/*
+*******************************************************************************
+*
+*   Copyright (C) 2001-2010, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+*******************************************************************************
+*   file name:  casetrn.cpp
+*   encoding:   US-ASCII
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2004sep03
+*   created by: Markus W. Scherer
+*
+*   Implementation class for lower-/upper-/title-casing transliterators.
+*/
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_TRANSLITERATION
+
+#include "unicode/uchar.h"
+#include "unicode/ustring.h"
+#include "tolowtrn.h"
+#include "ucase.h"
+#include "cpputils.h"
+
+/* case context iterator using a Replaceable */
+U_CFUNC UChar32 U_CALLCONV
+utrans_rep_caseContextIterator(void *context, int8_t dir)
+{
+    U_NAMESPACE_USE
+
+    UCaseContext *csc=(UCaseContext *)context;
+    Replaceable *rep=(Replaceable *)csc->p;
+    UChar32 c;
+
+    if(dir<0) {
+        /* reset for backward iteration */
+        csc->index=csc->cpStart;
+        csc->dir=dir;
+    } else if(dir>0) {
+        /* reset for forward iteration */
+        csc->index=csc->cpLimit;
+        csc->dir=dir;
+    } else {
+        /* continue current iteration direction */
+        dir=csc->dir;
+    }
+
+    // automatically adjust start and limit if the Replaceable disagrees
+    // with the original values
+    if(dir<0) {
+        if(csc->start<csc->index) {
+            c=rep->char32At(csc->index-1);
+            if(c<0) {
+                csc->start=csc->index;
+            } else {
+                csc->index-=U16_LENGTH(c);
+                return c;
+            }
+        }
+    } else {
+        // detect, and store in csc->b1, if we hit the limit
+        if(csc->index<csc->limit) {
+            c=rep->char32At(csc->index);
+            if(c<0) {
+                csc->limit=csc->index;
+                csc->b1=TRUE;
+            } else {
+                csc->index+=U16_LENGTH(c);
+                return c;
+            }
+        } else {
+            csc->b1=TRUE;
+        }
+    }
+    return U_SENTINEL;
+}
+
+U_NAMESPACE_BEGIN
+
+UOBJECT_DEFINE_ABSTRACT_RTTI_IMPLEMENTATION(CaseMapTransliterator)
+
+/**
+ * Constructs a transliterator.
+ */
+CaseMapTransliterator::CaseMapTransliterator(const UnicodeString &id, UCaseMapFull *map) : 
+    Transliterator(id, 0),
+    fCsp(ucase_getSingleton()),
+    fMap(map)
+{
+    // TODO test incremental mode with context-sensitive text (e.g. greek sigma)
+    // TODO need to call setMaximumContextLength()?!
+}
+
+/**
+ * Destructor.
+ */
+CaseMapTransliterator::~CaseMapTransliterator() {
+}
+
+/**
+ * Copy constructor.
+ */
+CaseMapTransliterator::CaseMapTransliterator(const CaseMapTransliterator& o) :
+    Transliterator(o),
+    fCsp(o.fCsp), fMap(o.fMap)
+{
+}
+
+/**
+ * Assignment operator.
+ */
+/*CaseMapTransliterator& CaseMapTransliterator::operator=(const CaseMapTransliterator& o) {
+    Transliterator::operator=(o);
+    fCsp = o.fCsp;
+    fMap = o.fMap;
+    return *this;
+}*/
+
+/**
+ * Transliterator API.
+ */
+/*Transliterator* CaseMapTransliterator::clone(void) const {
+    return new CaseMapTransliterator(*this);
+}*/
+
+/**
+ * Implements {@link Transliterator#handleTransliterate}.
+ */
+void CaseMapTransliterator::handleTransliterate(Replaceable& text,
+                                 UTransPosition& offsets, 
+                                 UBool isIncremental) const
+{
+    if (offsets.start >= offsets.limit) {
+        return;
+    }
+
+    UCaseContext csc;
+    uprv_memset(&csc, 0, sizeof(csc));
+    csc.p = &text;
+    csc.start = offsets.contextStart;
+    csc.limit = offsets.contextLimit;
+
+    UnicodeString tmp;
+    const UChar *s;
+    UChar32 c;
+    int32_t textPos, delta, result, locCache=0;
+
+    for(textPos=offsets.start; textPos<offsets.limit;) {
+        csc.cpStart=textPos;
+        c=text.char32At(textPos);
+        csc.cpLimit=textPos+=U16_LENGTH(c);
+
+        result=fMap(fCsp, c, utrans_rep_caseContextIterator, &csc, &s, "", &locCache);
+
+        if(csc.b1 && isIncremental) {
+            // fMap() tried to look beyond the context limit
+            // wait for more input
+            offsets.start=csc.cpStart;
+            return;
+        }
+
+        if(result>=0) {
+            // replace the current code point with its full case mapping result
+            // see UCASE_MAX_STRING_LENGTH
+            if(result<=UCASE_MAX_STRING_LENGTH) {
+                // string s[result]
+                tmp.setTo(FALSE, s, result);
+                delta=result-U16_LENGTH(c);
+            } else {
+                // single code point
+                tmp.setTo(result);
+                delta=tmp.length()-U16_LENGTH(c);
+            }
+            text.handleReplaceBetween(csc.cpStart, textPos, tmp);
+            if(delta!=0) {
+                textPos+=delta;
+                csc.limit=offsets.contextLimit+=delta;
+                offsets.limit+=delta;
+            }
+        }
+    }
+    offsets.start=textPos;
+}
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_TRANSLITERATION */