Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1739 insertions, 0 deletions

diff --git a/intl/icu/source/common/ucase.cpp b/intl/icu/source/common/ucase.cpp
new file mode 100644
index 0000000000..392e1266ae
--- /dev/null
+++ b/intl/icu/source/common/ucase.cpp
@@ -0,0 +1,1739 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+*******************************************************************************
+*
+*   Copyright (C) 2004-2014, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+*******************************************************************************
+*   file name:  ucase.cpp
+*   encoding:   UTF-8
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2004aug30
+*   created by: Markus W. Scherer
+*
+*   Low-level Unicode character/string case mapping code.
+*   Much code moved here (and modified) from uchar.c.
+*/
+
+#include "unicode/utypes.h"
+#include "unicode/unistr.h"
+#include "unicode/uset.h"
+#include "unicode/utf16.h"
+#include "cmemory.h"
+#include "uassert.h"
+#include "ucase.h"
+#include "umutex.h"
+#include "utrie2.h"
+
+/* ucase_props_data.h is machine-generated by genprops/casepropsbuilder.cpp */
+#define INCLUDED_FROM_UCASE_CPP
+#include "ucase_props_data.h"
+
+/* set of property starts for UnicodeSet ------------------------------------ */
+
+static UBool U_CALLCONV
+_enumPropertyStartsRange(const void *context, UChar32 start, UChar32 /*end*/, uint32_t /*value*/) {
+    /* add the start code point to the USet */
+    const USetAdder *sa=(const USetAdder *)context;
+    sa->add(sa->set, start);
+    return true;
+}
+
+U_CFUNC void U_EXPORT2
+ucase_addPropertyStarts(const USetAdder *sa, UErrorCode *pErrorCode) {
+    if(U_FAILURE(*pErrorCode)) {
+        return;
+    }
+
+    /* add the start code point of each same-value range of the trie */
+    utrie2_enum(&ucase_props_singleton.trie, nullptr, _enumPropertyStartsRange, sa);
+
+    /* add code points with hardcoded properties, plus the ones following them */
+
+    /* (none right now, see comment below) */
+
+    /*
+     * Omit code points with hardcoded specialcasing properties
+     * because we do not build property UnicodeSets for them right now.
+     */
+}
+
+/* data access primitives --------------------------------------------------- */
+
+U_CAPI const struct UCaseProps * U_EXPORT2
+ucase_getSingleton(int32_t *pExceptionsLength, int32_t *pUnfoldLength) {
+    *pExceptionsLength = UPRV_LENGTHOF(ucase_props_exceptions);
+    *pUnfoldLength = UPRV_LENGTHOF(ucase_props_unfold);
+    return &ucase_props_singleton;
+}
+
+U_CFUNC const UTrie2 * U_EXPORT2
+ucase_getTrie() {
+    return &ucase_props_singleton.trie;
+}
+
+#define GET_EXCEPTIONS(csp, props) ((csp)->exceptions+((props)>>UCASE_EXC_SHIFT))
+
+/* number of bits in an 8-bit integer value */
+static const uint8_t flagsOffset[256]={
+    0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
+    1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+    1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+    2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+    1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+    2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+    2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+    3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+    1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+    2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+    2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+    3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+    2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+    3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+    3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+    4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
+};
+
+#define HAS_SLOT(flags, idx) ((flags)&(1<<(idx)))
+#define SLOT_OFFSET(flags, idx) flagsOffset[(flags)&((1<<(idx))-1)]
+
+/*
+ * Get the value of an optional-value slot where HAS_SLOT(excWord, idx).
+ *
+ * @param excWord (in) initial exceptions word
+ * @param idx (in) desired slot index
+ * @param pExc16 (in/out) const uint16_t * after excWord=*pExc16++;
+ *               moved to the last uint16_t of the value, use +1 for beginning of next slot
+ * @param value (out) int32_t or uint32_t output if hasSlot, otherwise not modified
+ */
+#define GET_SLOT_VALUE(excWord, idx, pExc16, value) UPRV_BLOCK_MACRO_BEGIN { \
+    if(((excWord)&UCASE_EXC_DOUBLE_SLOTS)==0) { \
+        (pExc16)+=SLOT_OFFSET(excWord, idx); \
+        (value)=*pExc16; \
+    } else { \
+        (pExc16)+=2*SLOT_OFFSET(excWord, idx); \
+        (value)=*pExc16++; \
+        (value)=((value)<<16)|*pExc16; \
+    } \
+} UPRV_BLOCK_MACRO_END
+
+/* simple case mappings ----------------------------------------------------- */
+
+U_CAPI UChar32 U_EXPORT2
+ucase_tolower(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_IS_UPPER_OR_TITLE(props)) {
+            c+=UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        uint16_t excWord=*pe++;
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_IS_UPPER_OR_TITLE(props)) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_LOWER)) {
+            GET_SLOT_VALUE(excWord, UCASE_EXC_LOWER, pe, c);
+        }
+    }
+    return c;
+}
+
+U_CAPI UChar32 U_EXPORT2
+ucase_toupper(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_GET_TYPE(props)==UCASE_LOWER) {
+            c+=UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        uint16_t excWord=*pe++;
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_GET_TYPE(props)==UCASE_LOWER) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_UPPER)) {
+            GET_SLOT_VALUE(excWord, UCASE_EXC_UPPER, pe, c);
+        }
+    }
+    return c;
+}
+
+U_CAPI UChar32 U_EXPORT2
+ucase_totitle(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_GET_TYPE(props)==UCASE_LOWER) {
+            c+=UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        uint16_t excWord=*pe++;
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_GET_TYPE(props)==UCASE_LOWER) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        int32_t idx;
+        if(HAS_SLOT(excWord, UCASE_EXC_TITLE)) {
+            idx=UCASE_EXC_TITLE;
+        } else if(HAS_SLOT(excWord, UCASE_EXC_UPPER)) {
+            idx=UCASE_EXC_UPPER;
+        } else {
+            return c;
+        }
+        GET_SLOT_VALUE(excWord, idx, pe, c);
+    }
+    return c;
+}
+
+static const char16_t iDot[2] = { 0x69, 0x307 };
+static const char16_t jDot[2] = { 0x6a, 0x307 };
+static const char16_t iOgonekDot[3] = { 0x12f, 0x307 };
+static const char16_t iDotGrave[3] = { 0x69, 0x307, 0x300 };
+static const char16_t iDotAcute[3] = { 0x69, 0x307, 0x301 };
+static const char16_t iDotTilde[3] = { 0x69, 0x307, 0x303 };
+
+
+U_CFUNC void U_EXPORT2
+ucase_addCaseClosure(UChar32 c, const USetAdder *sa) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_GET_TYPE(props)!=UCASE_NONE) {
+            /* add the one simple case mapping, no matter what type it is */
+            int32_t delta=UCASE_GET_DELTA(props);
+            if(delta!=0) {
+                sa->add(sa->set, c+delta);
+            }
+        }
+    } else {
+        /*
+         * c has exceptions, so there may be multiple simple and/or
+         * full case mappings. Add them all.
+         */
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        uint16_t excWord=*pe++;
+        const uint16_t *pe0=pe;
+
+        // Hardcode the case closure of i and its relatives and ignore the
+        // data file data for these characters.
+        // The Turkic dotless i and dotted I with their case mapping conditions
+        // and case folding option make the related characters behave specially.
+        // This code matches their closure behavior to their case folding behavior.
+        if (excWord&UCASE_EXC_CONDITIONAL_FOLD) {
+            // These characters have Turkic case foldings. Hardcode their closure.
+            if (c == 0x49) {
+                // Regular i and I are in one equivalence class.
+                sa->add(sa->set, 0x69);
+                return;
+            } else if (c == 0x130) {
+                // Dotted I is in a class with <0069 0307>
+                // (for canonical equivalence with <0049 0307>).
+                sa->addString(sa->set, iDot, 2);
+                return;
+            }
+        } else if (c == 0x69) {
+            sa->add(sa->set, 0x49);
+            return;
+        } else if (c == 0x131) {
+            // Dotless i is in a class by itself.
+            return;
+        }
+
+        /* add all simple case mappings */
+        for(int32_t idx=UCASE_EXC_LOWER; idx<=UCASE_EXC_TITLE; ++idx) {
+            if(HAS_SLOT(excWord, idx)) {
+                pe=pe0;
+                UChar32 mapping;
+                GET_SLOT_VALUE(excWord, idx, pe, mapping);
+                sa->add(sa->set, mapping);
+            }
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA)) {
+            pe=pe0;
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe, delta);
+            sa->add(sa->set, (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta);
+        }
+
+        /* get the closure string pointer & length */
+        const char16_t *closure;
+        int32_t closureLength;
+        if(HAS_SLOT(excWord, UCASE_EXC_CLOSURE)) {
+            pe=pe0;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_CLOSURE, pe, closureLength);
+            closureLength&=UCASE_CLOSURE_MAX_LENGTH; /* higher bits are reserved */
+            closure=(const char16_t *)pe+1; /* behind this slot, unless there are full case mappings */
+        } else {
+            closureLength=0;
+            closure=nullptr;
+        }
+
+        /* add the full case folding */
+        if(HAS_SLOT(excWord, UCASE_EXC_FULL_MAPPINGS)) {
+            pe=pe0;
+            int32_t fullLength;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_FULL_MAPPINGS, pe, fullLength);
+
+            /* start of full case mapping strings */
+            ++pe;
+
+            fullLength&=0xffff; /* bits 16 and higher are reserved */
+
+            /* skip the lowercase result string */
+            pe+=fullLength&UCASE_FULL_LOWER;
+            fullLength>>=4;
+
+            /* add the full case folding string */
+            int32_t length=fullLength&0xf;
+            if(length!=0) {
+                sa->addString(sa->set, (const char16_t *)pe, length);
+                pe+=length;
+            }
+
+            /* skip the uppercase and titlecase strings */
+            fullLength>>=4;
+            pe+=fullLength&0xf;
+            fullLength>>=4;
+            pe+=fullLength;
+
+            closure=(const char16_t *)pe; /* behind full case mappings */
+        }
+
+        /* add each code point in the closure string */
+        for(int32_t idx=0; idx<closureLength;) {
+            UChar32 mapping;
+            U16_NEXT_UNSAFE(closure, idx, mapping);
+            sa->add(sa->set, mapping);
+        }
+    }
+}
+
+namespace {
+
+/**
+ * Add the simple case closure mapping,
+ * except if there is not actually an scf relationship between the two characters.
+ * TODO: Unicode should probably add the corresponding scf mappings.
+ * See https://crbug.com/v8/13377 and Unicode-internal PAG issue #23.
+ * If & when those scf mappings are added, we should be able to remove all of these exceptions.
+ */
+void addOneSimpleCaseClosure(UChar32 c, UChar32 t, const USetAdder *sa) {
+    switch (c) {
+    case 0x0390:
+        if (t == 0x1FD3) { return; }
+        break;
+    case 0x03B0:
+        if (t == 0x1FE3) { return; }
+        break;
+    case 0x1FD3:
+        if (t == 0x0390) { return; }
+        break;
+    case 0x1FE3:
+        if (t == 0x03B0) { return; }
+        break;
+    case 0xFB05:
+        if (t == 0xFB06) { return; }
+        break;
+    case 0xFB06:
+        if (t == 0xFB05) { return; }
+        break;
+    default:
+        break;
+    }
+    sa->add(sa->set, t);
+}
+
+}  // namespace
+
+U_CFUNC void U_EXPORT2
+ucase_addSimpleCaseClosure(UChar32 c, const USetAdder *sa) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_GET_TYPE(props)!=UCASE_NONE) {
+            /* add the one simple case mapping, no matter what type it is */
+            int32_t delta=UCASE_GET_DELTA(props);
+            if(delta!=0) {
+                sa->add(sa->set, c+delta);
+            }
+        }
+    } else {
+        // c has exceptions. Add the mappings relevant for scf=Simple_Case_Folding.
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        uint16_t excWord=*pe++;
+        const uint16_t *pe0=pe;
+
+        // Hardcode the case closure of i and its relatives and ignore the
+        // data file data for these characters, like in ucase_addCaseClosure().
+        if (excWord&UCASE_EXC_CONDITIONAL_FOLD) {
+            // These characters have Turkic case foldings. Hardcode their closure.
+            if (c == 0x49) {
+                // Regular i and I are in one equivalence class.
+                sa->add(sa->set, 0x69);
+                return;
+            } else if (c == 0x130) {
+                // For scf=Simple_Case_Folding, dotted I is in a class by itself.
+                return;
+            }
+        } else if (c == 0x69) {
+            sa->add(sa->set, 0x49);
+            return;
+        } else if (c == 0x131) {
+            // Dotless i is in a class by itself.
+            return;
+        }
+
+        // Add all simple case mappings.
+        for(int32_t idx=UCASE_EXC_LOWER; idx<=UCASE_EXC_TITLE; ++idx) {
+            if(HAS_SLOT(excWord, idx)) {
+                pe=pe0;
+                UChar32 mapping;
+                GET_SLOT_VALUE(excWord, idx, pe, mapping);
+                addOneSimpleCaseClosure(c, mapping, sa);
+            }
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA)) {
+            pe=pe0;
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe, delta);
+            UChar32 mapping = (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+            addOneSimpleCaseClosure(c, mapping, sa);
+        }
+
+        /* get the closure string pointer & length */
+        const char16_t *closure;
+        int32_t closureLength;
+        if(HAS_SLOT(excWord, UCASE_EXC_CLOSURE)) {
+            pe=pe0;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_CLOSURE, pe, closureLength);
+            closureLength&=UCASE_CLOSURE_MAX_LENGTH; /* higher bits are reserved */
+            closure=(const char16_t *)pe+1; /* behind this slot, unless there are full case mappings */
+        } else {
+            closureLength=0;
+            closure=nullptr;
+        }
+
+        // Skip the full case mappings.
+        if(closureLength > 0 && HAS_SLOT(excWord, UCASE_EXC_FULL_MAPPINGS)) {
+            pe=pe0;
+            int32_t fullLength;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_FULL_MAPPINGS, pe, fullLength);
+
+            /* start of full case mapping strings */
+            ++pe;
+
+            fullLength&=0xffff; /* bits 16 and higher are reserved */
+
+            // Skip all 4 full case mappings.
+            pe+=fullLength&UCASE_FULL_LOWER;
+            fullLength>>=4;
+            pe+=fullLength&0xf;
+            fullLength>>=4;
+            pe+=fullLength&0xf;
+            fullLength>>=4;
+            pe+=fullLength;
+
+            closure=(const char16_t *)pe; /* behind full case mappings */
+        }
+
+        // Add each code point in the closure string whose scf maps back to c.
+        for(int32_t idx=0; idx<closureLength;) {
+            UChar32 mapping;
+            U16_NEXT_UNSAFE(closure, idx, mapping);
+            addOneSimpleCaseClosure(c, mapping, sa);
+        }
+    }
+}
+
+/*
+ * compare s, which has a length, with t, which has a maximum length or is NUL-terminated
+ * must be length>0 and max>0 and length<=max
+ */
+static inline int32_t
+strcmpMax(const char16_t *s, int32_t length, const char16_t *t, int32_t max) {
+    int32_t c1, c2;
+
+    max-=length; /* we require length<=max, so no need to decrement max in the loop */
+    do {
+        c1=*s++;
+        c2=*t++;
+        if(c2==0) {
+            return 1; /* reached the end of t but not of s */
+        }
+        c1-=c2;
+        if(c1!=0) {
+            return c1; /* return difference result */
+        }
+    } while(--length>0);
+    /* ends with length==0 */
+
+    if(max==0 || *t==0) {
+        return 0; /* equal to length of both strings */
+    } else {
+        return -max; /* return length difference */
+    }
+}
+
+U_CFUNC UBool U_EXPORT2
+ucase_addStringCaseClosure(const char16_t *s, int32_t length, const USetAdder *sa) {
+    int32_t i, start, limit, result, unfoldRows, unfoldRowWidth, unfoldStringWidth;
+
+    if(ucase_props_singleton.unfold==nullptr || s==nullptr) {
+        return false; /* no reverse case folding data, or no string */
+    }
+    if(length<=1) {
+        /* the string is too short to find any match */
+        /*
+         * more precise would be:
+         * if(!u_strHasMoreChar32Than(s, length, 1))
+         * but this does not make much practical difference because
+         * a single supplementary code point would just not be found
+         */
+        return false;
+    }
+
+    const uint16_t *unfold=ucase_props_singleton.unfold;
+    unfoldRows=unfold[UCASE_UNFOLD_ROWS];
+    unfoldRowWidth=unfold[UCASE_UNFOLD_ROW_WIDTH];
+    unfoldStringWidth=unfold[UCASE_UNFOLD_STRING_WIDTH];
+    unfold+=unfoldRowWidth;
+
+    if(length>unfoldStringWidth) {
+        /* the string is too long to find any match */
+        return false;
+    }
+
+    /* do a binary search for the string */
+    start=0;
+    limit=unfoldRows;
+    while(start<limit) {
+        i=(start+limit)/2;
+        const char16_t *p=reinterpret_cast<const char16_t *>(unfold+(i*unfoldRowWidth));
+        result=strcmpMax(s, length, p, unfoldStringWidth);
+
+        if(result==0) {
+            /* found the string: add each code point, and its case closure */
+            UChar32 c;
+
+            for(i=unfoldStringWidth; i<unfoldRowWidth && p[i]!=0;) {
+                U16_NEXT_UNSAFE(p, i, c);
+                sa->add(sa->set, c);
+                ucase_addCaseClosure(c, sa);
+            }
+            return true;
+        } else if(result<0) {
+            limit=i;
+        } else /* result>0 */ {
+            start=i+1;
+        }
+    }
+
+    return false; /* string not found */
+}
+
+U_NAMESPACE_BEGIN
+
+FullCaseFoldingIterator::FullCaseFoldingIterator()
+        : unfold(reinterpret_cast<const char16_t *>(ucase_props_singleton.unfold)),
+          unfoldRows(unfold[UCASE_UNFOLD_ROWS]),
+          unfoldRowWidth(unfold[UCASE_UNFOLD_ROW_WIDTH]),
+          unfoldStringWidth(unfold[UCASE_UNFOLD_STRING_WIDTH]),
+          currentRow(0),
+          rowCpIndex(unfoldStringWidth) {
+    unfold+=unfoldRowWidth;
+}
+
+UChar32
+FullCaseFoldingIterator::next(UnicodeString &full) {
+    // Advance past the last-delivered code point.
+    const char16_t *p=unfold+(currentRow*unfoldRowWidth);
+    if(rowCpIndex>=unfoldRowWidth || p[rowCpIndex]==0) {
+        ++currentRow;
+        p+=unfoldRowWidth;
+        rowCpIndex=unfoldStringWidth;
+    }
+    if(currentRow>=unfoldRows) { return U_SENTINEL; }
+    // Set "full" to the NUL-terminated string in the first unfold column.
+    int32_t length=unfoldStringWidth;
+    while(length>0 && p[length-1]==0) { --length; }
+    full.setTo(false, p, length);
+    // Return the code point.
+    UChar32 c;
+    U16_NEXT_UNSAFE(p, rowCpIndex, c);
+    return c;
+}
+
+namespace LatinCase {
+
+const int8_t TO_LOWER_NORMAL[LIMIT] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
+    32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, EXC, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
+    32, 32, 32, 32, 32, 32, 32, 0, 32, 32, 32, 32, 32, 32, 32, EXC,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    EXC, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1,
+
+    0, 1, 0, 1, 0, 1, 0, 1, 0, EXC, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, -121, 1, 0, 1, 0, 1, 0, EXC
+};
+
+const int8_t TO_LOWER_TR_LT[LIMIT] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 32, 32, 32, 32, 32, 32, 32, 32, EXC, EXC, 32, 32, 32, 32, 32,
+    32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, EXC, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, EXC, EXC, 32, 32,
+    32, 32, 32, 32, 32, 32, 32, 0, 32, 32, 32, 32, 32, 32, 32, EXC,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, EXC, 0, 1, 0, 1, 0, EXC, 0,
+    EXC, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1,
+
+    0, 1, 0, 1, 0, 1, 0, 1, 0, EXC, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,
+    1, 0, 1, 0, 1, 0, 1, 0, -121, 1, 0, 1, 0, 1, 0, EXC
+};
+
+const int8_t TO_UPPER_NORMAL[LIMIT] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32,
+    -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, EXC, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, EXC,
+    -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32,
+    -32, -32, -32, -32, -32, -32, -32, 0, -32, -32, -32, -32, -32, -32, -32, 121,
+
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, EXC, 0, -1, 0, -1, 0, -1, 0, 0, -1, 0, -1, 0, -1, 0,
+
+    -1, 0, -1, 0, -1, 0, -1, 0, -1, EXC, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, 0, -1, 0, -1, 0, -1, EXC
+};
+
+const int8_t TO_UPPER_TR[LIMIT] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, -32, -32, -32, -32, -32, -32, -32, -32, EXC, -32, -32, -32, -32, -32, -32,
+    -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, EXC, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, EXC,
+    -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32, -32,
+    -32, -32, -32, -32, -32, -32, -32, 0, -32, -32, -32, -32, -32, -32, -32, 121,
+
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, EXC, 0, -1, 0, -1, 0, -1, 0, 0, -1, 0, -1, 0, -1, 0,
+
+    -1, 0, -1, 0, -1, 0, -1, 0, -1, EXC, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1, 0, -1,
+    0, -1, 0, -1, 0, -1, 0, -1, 0, 0, -1, 0, -1, 0, -1, EXC
+};
+
+}  // namespace LatinCase
+
+U_NAMESPACE_END
+
+/** @return UCASE_NONE, UCASE_LOWER, UCASE_UPPER, UCASE_TITLE */
+U_CAPI int32_t U_EXPORT2
+ucase_getType(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    return UCASE_GET_TYPE(props);
+}
+
+/** @return same as ucase_getType() and set bit 2 if c is case-ignorable */
+U_CAPI int32_t U_EXPORT2
+ucase_getTypeOrIgnorable(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    return UCASE_GET_TYPE_AND_IGNORABLE(props);
+}
+
+/** @return UCASE_NO_DOT, UCASE_SOFT_DOTTED, UCASE_ABOVE, UCASE_OTHER_ACCENT */
+static inline int32_t
+getDotType(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        return props&UCASE_DOT_MASK;
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        return (*pe>>UCASE_EXC_DOT_SHIFT)&UCASE_DOT_MASK;
+    }
+}
+
+U_CAPI UBool U_EXPORT2
+ucase_isSoftDotted(UChar32 c) {
+    return (UBool)(getDotType(c)==UCASE_SOFT_DOTTED);
+}
+
+U_CAPI UBool U_EXPORT2
+ucase_isCaseSensitive(UChar32 c) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        return (UBool)((props&UCASE_SENSITIVE)!=0);
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        return (UBool)((*pe&UCASE_EXC_SENSITIVE)!=0);
+    }
+}
+
+/* string casing ------------------------------------------------------------ */
+
+/*
+ * These internal functions form the core of string case mappings.
+ * They map single code points to result code points or strings and take
+ * all necessary conditions (context, locale ID, options) into account.
+ *
+ * They do not iterate over the source or write to the destination
+ * so that the same functions are useful for non-standard string storage,
+ * such as in a Replaceable (for Transliterator) or UTF-8/32 strings etc.
+ * For the same reason, the "surrounding text" context is passed in as a
+ * UCaseContextIterator which does not make any assumptions about
+ * the underlying storage.
+ *
+ * This section contains helper functions that check for conditions
+ * in the input text surrounding the current code point
+ * according to SpecialCasing.txt.
+ *
+ * Each helper function gets the index
+ * - after the current code point if it looks at following text
+ * - before the current code point if it looks at preceding text
+ *
+ * Unicode 3.2 UAX 21 "Case Mappings" defines the conditions as follows:
+ *
+ * Final_Sigma
+ *   C is preceded by a sequence consisting of
+ *     a cased letter and a case-ignorable sequence,
+ *   and C is not followed by a sequence consisting of
+ *     an ignorable sequence and then a cased letter.
+ *
+ * More_Above
+ *   C is followed by one or more characters of combining class 230 (ABOVE)
+ *   in the combining character sequence.
+ *
+ * After_Soft_Dotted
+ *   The last preceding character with combining class of zero before C
+ *   was Soft_Dotted,
+ *   and there is no intervening combining character class 230 (ABOVE).
+ *
+ * Before_Dot
+ *   C is followed by combining dot above (U+0307).
+ *   Any sequence of characters with a combining class that is neither 0 nor 230
+ *   may intervene between the current character and the combining dot above.
+ *
+ * The erratum from 2002-10-31 adds the condition
+ *
+ * After_I
+ *   The last preceding base character was an uppercase I, and there is no
+ *   intervening combining character class 230 (ABOVE).
+ *
+ *   (See Jitterbug 2344 and the comments on After_I below.)
+ *
+ * Helper definitions in Unicode 3.2 UAX 21:
+ *
+ * D1. A character C is defined to be cased
+ *     if it meets any of the following criteria:
+ *
+ *   - The general category of C is Titlecase Letter (Lt)
+ *   - In [CoreProps], C has one of the properties Uppercase, or Lowercase
+ *   - Given D = NFD(C), then it is not the case that:
+ *     D = UCD_lower(D) = UCD_upper(D) = UCD_title(D)
+ *     (This third criterion does not add any characters to the list
+ *      for Unicode 3.2. Ignored.)
+ *
+ * D2. A character C is defined to be case-ignorable
+ *     if it meets either of the following criteria:
+ *
+ *   - The general category of C is
+ *     Nonspacing Mark (Mn), or Enclosing Mark (Me), or Format Control (Cf), or
+ *     Letter Modifier (Lm), or Symbol Modifier (Sk)
+ *   - C is one of the following characters
+ *     U+0027 APOSTROPHE
+ *     U+00AD SOFT HYPHEN (SHY)
+ *     U+2019 RIGHT SINGLE QUOTATION MARK
+ *            (the preferred character for apostrophe)
+ *
+ * D3. A case-ignorable sequence is a sequence of
+ *     zero or more case-ignorable characters.
+ */
+
+#define is_d(c) ((c)=='d' || (c)=='D')
+#define is_e(c) ((c)=='e' || (c)=='E')
+#define is_i(c) ((c)=='i' || (c)=='I')
+#define is_l(c) ((c)=='l' || (c)=='L')
+#define is_r(c) ((c)=='r' || (c)=='R')
+#define is_t(c) ((c)=='t' || (c)=='T')
+#define is_u(c) ((c)=='u' || (c)=='U')
+#define is_y(c) ((c)=='y' || (c)=='Y')
+#define is_z(c) ((c)=='z' || (c)=='Z')
+
+/* separator? */
+#define is_sep(c) ((c)=='_' || (c)=='-' || (c)==0)
+
+/**
+ * Requires non-nullptr locale ID but otherwise does the equivalent of
+ * checking for language codes as if uloc_getLanguage() were called:
+ * Accepts both 2- and 3-letter codes and accepts case variants.
+ */
+U_CFUNC int32_t
+ucase_getCaseLocale(const char *locale) {
+    /*
+     * This function used to use uloc_getLanguage(), but the current code
+     * removes the dependency of this low-level code on uloc implementation code
+     * and is faster because not the whole locale ID has to be
+     * examined and copied/transformed.
+     *
+     * Because this code does not want to depend on uloc, the caller must
+     * pass in a non-nullptr locale, i.e., may need to call uloc_getDefault().
+     */
+    char c=*locale++;
+    // Fastpath for English "en" which is often used for default (=root locale) case mappings,
+    // and for Chinese "zh": Very common but no special case mapping behavior.
+    // Then check lowercase vs. uppercase to reduce the number of comparisons
+    // for other locales without special behavior.
+    if(c=='e') {
+        /* el or ell? */
+        c=*locale++;
+        if(is_l(c)) {
+            c=*locale++;
+            if(is_l(c)) {
+                c=*locale;
+            }
+            if(is_sep(c)) {
+                return UCASE_LOC_GREEK;
+            }
+        }
+        // en, es, ... -> root
+    } else if(c=='z') {
+        return UCASE_LOC_ROOT;
+#if U_CHARSET_FAMILY==U_ASCII_FAMILY
+    } else if(c>='a') {  // ASCII a-z = 0x61..0x7a, after A-Z
+#elif U_CHARSET_FAMILY==U_EBCDIC_FAMILY
+    } else if(c<='z') {  // EBCDIC a-z = 0x81..0xa9 with two gaps, before A-Z
+#else
+#   error Unknown charset family!
+#endif
+        // lowercase c
+        if(c=='t') {
+            /* tr or tur? */
+            c=*locale++;
+            if(is_u(c)) {
+                c=*locale++;
+            }
+            if(is_r(c)) {
+                c=*locale;
+                if(is_sep(c)) {
+                    return UCASE_LOC_TURKISH;
+                }
+            }
+        } else if(c=='a') {
+            /* az or aze? */
+            c=*locale++;
+            if(is_z(c)) {
+                c=*locale++;
+                if(is_e(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_TURKISH;
+                }
+            }
+        } else if(c=='l') {
+            /* lt or lit? */
+            c=*locale++;
+            if(is_i(c)) {
+                c=*locale++;
+            }
+            if(is_t(c)) {
+                c=*locale;
+                if(is_sep(c)) {
+                    return UCASE_LOC_LITHUANIAN;
+                }
+            }
+        } else if(c=='n') {
+            /* nl or nld? */
+            c=*locale++;
+            if(is_l(c)) {
+                c=*locale++;
+                if(is_d(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_DUTCH;
+                }
+            }
+        } else if(c=='h') {
+            /* hy or hye? *not* hyw */
+            c=*locale++;
+            if(is_y(c)) {
+                c=*locale++;
+                if(is_e(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_ARMENIAN;
+                }
+            }
+        }
+    } else {
+        // uppercase c
+        // Same code as for lowercase c but also check for 'E'.
+        if(c=='T') {
+            /* tr or tur? */
+            c=*locale++;
+            if(is_u(c)) {
+                c=*locale++;
+            }
+            if(is_r(c)) {
+                c=*locale;
+                if(is_sep(c)) {
+                    return UCASE_LOC_TURKISH;
+                }
+            }
+        } else if(c=='A') {
+            /* az or aze? */
+            c=*locale++;
+            if(is_z(c)) {
+                c=*locale++;
+                if(is_e(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_TURKISH;
+                }
+            }
+        } else if(c=='L') {
+            /* lt or lit? */
+            c=*locale++;
+            if(is_i(c)) {
+                c=*locale++;
+            }
+            if(is_t(c)) {
+                c=*locale;
+                if(is_sep(c)) {
+                    return UCASE_LOC_LITHUANIAN;
+                }
+            }
+        } else if(c=='E') {
+            /* el or ell? */
+            c=*locale++;
+            if(is_l(c)) {
+                c=*locale++;
+                if(is_l(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_GREEK;
+                }
+            }
+        } else if(c=='N') {
+            /* nl or nld? */
+            c=*locale++;
+            if(is_l(c)) {
+                c=*locale++;
+                if(is_d(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_DUTCH;
+                }
+            }
+        } else if(c=='H') {
+            /* hy or hye? *not* hyw */
+            c=*locale++;
+            if(is_y(c)) {
+                c=*locale++;
+                if(is_e(c)) {
+                    c=*locale;
+                }
+                if(is_sep(c)) {
+                    return UCASE_LOC_ARMENIAN;
+                }
+            }
+        }
+    }
+    return UCASE_LOC_ROOT;
+}
+
+/*
+ * Is followed by
+ *   {case-ignorable}* cased
+ * ?
+ * (dir determines looking forward/backward)
+ * If a character is case-ignorable, it is skipped regardless of whether
+ * it is also cased or not.
+ */
+static UBool
+isFollowedByCasedLetter(UCaseContextIterator *iter, void *context, int8_t dir) {
+    UChar32 c;
+
+    if(iter==nullptr) {
+        return false;
+    }
+
+    for(/* dir!=0 sets direction */; (c=iter(context, dir))>=0; dir=0) {
+        int32_t type=ucase_getTypeOrIgnorable(c);
+        if(type&4) {
+            /* case-ignorable, continue with the loop */
+        } else if(type!=UCASE_NONE) {
+            return true; /* followed by cased letter */
+        } else {
+            return false; /* uncased and not case-ignorable */
+        }
+    }
+
+    return false; /* not followed by cased letter */
+}
+
+/* Is preceded by Soft_Dotted character with no intervening cc=230 ? */
+static UBool
+isPrecededBySoftDotted(UCaseContextIterator *iter, void *context) {
+    UChar32 c;
+    int32_t dotType;
+    int8_t dir;
+
+    if(iter==nullptr) {
+        return false;
+    }
+
+    for(dir=-1; (c=iter(context, dir))>=0; dir=0) {
+        dotType=getDotType(c);
+        if(dotType==UCASE_SOFT_DOTTED) {
+            return true; /* preceded by TYPE_i */
+        } else if(dotType!=UCASE_OTHER_ACCENT) {
+            return false; /* preceded by different base character (not TYPE_i), or intervening cc==230 */
+        }
+    }
+
+    return false; /* not preceded by TYPE_i */
+}
+
+/*
+ * See Jitterbug 2344:
+ * The condition After_I for Turkic-lowercasing of U+0307 combining dot above
+ * is checked in ICU 2.0, 2.1, 2.6 but was not in 2.2 & 2.4 because
+ * we made those releases compatible with Unicode 3.2 which had not fixed
+ * a related bug in SpecialCasing.txt.
+ *
+ * From the Jitterbug 2344 text:
+ * ... this bug is listed as a Unicode erratum
+ * from 2002-10-31 at http://www.unicode.org/uni2errata/UnicodeErrata.html
+ * <quote>
+ * There are two errors in SpecialCasing.txt.
+ * 1. Missing semicolons on two lines. ... [irrelevant for ICU]
+ * 2. An incorrect context definition. Correct as follows:
+ * < 0307; ; 0307; 0307; tr After_Soft_Dotted; # COMBINING DOT ABOVE
+ * < 0307; ; 0307; 0307; az After_Soft_Dotted; # COMBINING DOT ABOVE
+ * ---
+ * > 0307; ; 0307; 0307; tr After_I; # COMBINING DOT ABOVE
+ * > 0307; ; 0307; 0307; az After_I; # COMBINING DOT ABOVE
+ * where the context After_I is defined as:
+ * The last preceding base character was an uppercase I, and there is no
+ * intervening combining character class 230 (ABOVE).
+ * </quote>
+ *
+ * Note that SpecialCasing.txt even in Unicode 3.2 described the condition as:
+ *
+ * # When lowercasing, remove dot_above in the sequence I + dot_above, which will turn into i.
+ * # This matches the behavior of the canonically equivalent I-dot_above
+ *
+ * See also the description in this place in older versions of uchar.c (revision 1.100).
+ *
+ * Markus W. Scherer 2003-feb-15
+ */
+
+/* Is preceded by base character 'I' with no intervening cc=230 ? */
+static UBool
+isPrecededBy_I(UCaseContextIterator *iter, void *context) {
+    UChar32 c;
+    int32_t dotType;
+    int8_t dir;
+
+    if(iter==nullptr) {
+        return false;
+    }
+
+    for(dir=-1; (c=iter(context, dir))>=0; dir=0) {
+        if(c==0x49) {
+            return true; /* preceded by I */
+        }
+        dotType=getDotType(c);
+        if(dotType!=UCASE_OTHER_ACCENT) {
+            return false; /* preceded by different base character (not I), or intervening cc==230 */
+        }
+    }
+
+    return false; /* not preceded by I */
+}
+
+/* Is followed by one or more cc==230 ? */
+static UBool
+isFollowedByMoreAbove(UCaseContextIterator *iter, void *context) {
+    UChar32 c;
+    int32_t dotType;
+    int8_t dir;
+
+    if(iter==nullptr) {
+        return false;
+    }
+
+    for(dir=1; (c=iter(context, dir))>=0; dir=0) {
+        dotType=getDotType(c);
+        if(dotType==UCASE_ABOVE) {
+            return true; /* at least one cc==230 following */
+        } else if(dotType!=UCASE_OTHER_ACCENT) {
+            return false; /* next base character, no more cc==230 following */
+        }
+    }
+
+    return false; /* no more cc==230 following */
+}
+
+/* Is followed by a dot above (without cc==230 in between) ? */
+static UBool
+isFollowedByDotAbove(UCaseContextIterator *iter, void *context) {
+    UChar32 c;
+    int32_t dotType;
+    int8_t dir;
+
+    if(iter==nullptr) {
+        return false;
+    }
+
+    for(dir=1; (c=iter(context, dir))>=0; dir=0) {
+        if(c==0x307) {
+            return true;
+        }
+        dotType=getDotType(c);
+        if(dotType!=UCASE_OTHER_ACCENT) {
+            return false; /* next base character or cc==230 in between */
+        }
+    }
+
+    return false; /* no dot above following */
+}
+
+U_CAPI int32_t U_EXPORT2
+ucase_toFullLower(UChar32 c,
+                  UCaseContextIterator *iter, void *context,
+                  const char16_t **pString,
+                  int32_t loc) {
+    // The sign of the result has meaning, input must be non-negative so that it can be returned as is.
+    U_ASSERT(c >= 0);
+    UChar32 result=c;
+    // Reset the output pointer in case it was uninitialized.
+    *pString=nullptr;
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_IS_UPPER_OR_TITLE(props)) {
+            result=c+UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props), *pe2;
+        uint16_t excWord=*pe++;
+        int32_t full;
+
+        pe2=pe;
+
+        if(excWord&UCASE_EXC_CONDITIONAL_SPECIAL) {
+            /* use hardcoded conditions and mappings */
+
+            /*
+             * Test for conditional mappings first
+             *   (otherwise the unconditional default mappings are always taken),
+             * then test for characters that have unconditional mappings in SpecialCasing.txt,
+             * then get the UnicodeData.txt mappings.
+             */
+            if( loc==UCASE_LOC_LITHUANIAN &&
+                    /* base characters, find accents above */
+                    (((c==0x49 || c==0x4a || c==0x12e) &&
+                        isFollowedByMoreAbove(iter, context)) ||
+                    /* precomposed with accent above, no need to find one */
+                    (c==0xcc || c==0xcd || c==0x128))
+            ) {
+                /*
+                    # Lithuanian
+
+                    # Lithuanian retains the dot in a lowercase i when followed by accents.
+
+                    # Introduce an explicit dot above when lowercasing capital I's and J's
+                    # whenever there are more accents above.
+                    # (of the accents used in Lithuanian: grave, acute, tilde above, and ogonek)
+
+                    0049; 0069 0307; 0049; 0049; lt More_Above; # LATIN CAPITAL LETTER I
+                    004A; 006A 0307; 004A; 004A; lt More_Above; # LATIN CAPITAL LETTER J
+                    012E; 012F 0307; 012E; 012E; lt More_Above; # LATIN CAPITAL LETTER I WITH OGONEK
+                    00CC; 0069 0307 0300; 00CC; 00CC; lt; # LATIN CAPITAL LETTER I WITH GRAVE
+                    00CD; 0069 0307 0301; 00CD; 00CD; lt; # LATIN CAPITAL LETTER I WITH ACUTE
+                    0128; 0069 0307 0303; 0128; 0128; lt; # LATIN CAPITAL LETTER I WITH TILDE
+                 */
+                switch(c) {
+                case 0x49:  /* LATIN CAPITAL LETTER I */
+                    *pString=iDot;
+                    return 2;
+                case 0x4a:  /* LATIN CAPITAL LETTER J */
+                    *pString=jDot;
+                    return 2;
+                case 0x12e: /* LATIN CAPITAL LETTER I WITH OGONEK */
+                    *pString=iOgonekDot;
+                    return 2;
+                case 0xcc:  /* LATIN CAPITAL LETTER I WITH GRAVE */
+                    *pString=iDotGrave;
+                    return 3;
+                case 0xcd:  /* LATIN CAPITAL LETTER I WITH ACUTE */
+                    *pString=iDotAcute;
+                    return 3;
+                case 0x128: /* LATIN CAPITAL LETTER I WITH TILDE */
+                    *pString=iDotTilde;
+                    return 3;
+                default:
+                    return 0; /* will not occur */
+                }
+            /* # Turkish and Azeri */
+            } else if(loc==UCASE_LOC_TURKISH && c==0x130) {
+                /*
+                    # I and i-dotless; I-dot and i are case pairs in Turkish and Azeri
+                    # The following rules handle those cases.
+
+                    0130; 0069; 0130; 0130; tr # LATIN CAPITAL LETTER I WITH DOT ABOVE
+                    0130; 0069; 0130; 0130; az # LATIN CAPITAL LETTER I WITH DOT ABOVE
+                 */
+                return 0x69;
+            } else if(loc==UCASE_LOC_TURKISH && c==0x307 && isPrecededBy_I(iter, context)) {
+                /*
+                    # When lowercasing, remove dot_above in the sequence I + dot_above, which will turn into i.
+                    # This matches the behavior of the canonically equivalent I-dot_above
+
+                    0307; ; 0307; 0307; tr After_I; # COMBINING DOT ABOVE
+                    0307; ; 0307; 0307; az After_I; # COMBINING DOT ABOVE
+                 */
+                return 0; /* remove the dot (continue without output) */
+            } else if(loc==UCASE_LOC_TURKISH && c==0x49 && !isFollowedByDotAbove(iter, context)) {
+                /*
+                    # When lowercasing, unless an I is before a dot_above, it turns into a dotless i.
+
+                    0049; 0131; 0049; 0049; tr Not_Before_Dot; # LATIN CAPITAL LETTER I
+                    0049; 0131; 0049; 0049; az Not_Before_Dot; # LATIN CAPITAL LETTER I
+                 */
+                return 0x131;
+            } else if(c==0x130) {
+                /*
+                    # Preserve canonical equivalence for I with dot. Turkic is handled below.
+
+                    0130; 0069 0307; 0130; 0130; # LATIN CAPITAL LETTER I WITH DOT ABOVE
+                 */
+                *pString=iDot;
+                return 2;
+            } else if(  c==0x3a3 &&
+                        !isFollowedByCasedLetter(iter, context, 1) &&
+                        isFollowedByCasedLetter(iter, context, -1) /* -1=preceded */
+            ) {
+                /* greek capital sigma maps depending on surrounding cased letters (see SpecialCasing.txt) */
+                /*
+                    # Special case for final form of sigma
+
+                    03A3; 03C2; 03A3; 03A3; Final_Sigma; # GREEK CAPITAL LETTER SIGMA
+                 */
+                return 0x3c2; /* greek small final sigma */
+            } else {
+                /* no known conditional special case mapping, use a normal mapping */
+            }
+        } else if(HAS_SLOT(excWord, UCASE_EXC_FULL_MAPPINGS)) {
+            GET_SLOT_VALUE(excWord, UCASE_EXC_FULL_MAPPINGS, pe, full);
+            full&=UCASE_FULL_LOWER;
+            if(full!=0) {
+                /* set the output pointer to the lowercase mapping */
+                *pString=reinterpret_cast<const char16_t *>(pe+1);
+
+                /* return the string length */
+                return full;
+            }
+        }
+
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_IS_UPPER_OR_TITLE(props)) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe2, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_LOWER)) {
+            GET_SLOT_VALUE(excWord, UCASE_EXC_LOWER, pe2, result);
+        }
+    }
+
+    return (result==c) ? ~result : result;
+}
+
+/* internal */
+static int32_t
+toUpperOrTitle(UChar32 c,
+               UCaseContextIterator *iter, void *context,
+               const char16_t **pString,
+               int32_t loc,
+               UBool upperNotTitle) {
+    // The sign of the result has meaning, input must be non-negative so that it can be returned as is.
+    U_ASSERT(c >= 0);
+    UChar32 result=c;
+    // Reset the output pointer in case it was uninitialized.
+    *pString=nullptr;
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_GET_TYPE(props)==UCASE_LOWER) {
+            result=c+UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props), *pe2;
+        uint16_t excWord=*pe++;
+        int32_t full, idx;
+
+        pe2=pe;
+
+        if(excWord&UCASE_EXC_CONDITIONAL_SPECIAL) {
+            /* use hardcoded conditions and mappings */
+            if(loc==UCASE_LOC_TURKISH && c==0x69) {
+                /*
+                    # Turkish and Azeri
+
+                    # I and i-dotless; I-dot and i are case pairs in Turkish and Azeri
+                    # The following rules handle those cases.
+
+                    # When uppercasing, i turns into a dotted capital I
+
+                    0069; 0069; 0130; 0130; tr; # LATIN SMALL LETTER I
+                    0069; 0069; 0130; 0130; az; # LATIN SMALL LETTER I
+                */
+                return 0x130;
+            } else if(loc==UCASE_LOC_LITHUANIAN && c==0x307 && isPrecededBySoftDotted(iter, context)) {
+                /*
+                    # Lithuanian
+
+                    # Lithuanian retains the dot in a lowercase i when followed by accents.
+
+                    # Remove DOT ABOVE after "i" with upper or titlecase
+
+                    0307; 0307; ; ; lt After_Soft_Dotted; # COMBINING DOT ABOVE
+                 */
+                return 0; /* remove the dot (continue without output) */
+            } else if(c==0x0587) {
+                // See ICU-13416:
+                // և ligature ech-yiwn
+                // uppercases to ԵՒ=ech+yiwn by default and in Western Armenian,
+                // but to ԵՎ=ech+vew in Eastern Armenian.
+                if(loc==UCASE_LOC_ARMENIAN) {
+                    *pString=upperNotTitle ? u"ԵՎ" : u"Եվ";
+                } else {
+                    *pString=upperNotTitle ? u"ԵՒ" : u"Եւ";
+                }
+                return 2;
+            } else {
+                /* no known conditional special case mapping, use a normal mapping */
+            }
+        } else if(HAS_SLOT(excWord, UCASE_EXC_FULL_MAPPINGS)) {
+            GET_SLOT_VALUE(excWord, UCASE_EXC_FULL_MAPPINGS, pe, full);
+
+            /* start of full case mapping strings */
+            ++pe;
+
+            /* skip the lowercase and case-folding result strings */
+            pe+=full&UCASE_FULL_LOWER;
+            full>>=4;
+            pe+=full&0xf;
+            full>>=4;
+
+            if(upperNotTitle) {
+                full&=0xf;
+            } else {
+                /* skip the uppercase result string */
+                pe+=full&0xf;
+                full=(full>>4)&0xf;
+            }
+
+            if(full!=0) {
+                /* set the output pointer to the result string */
+                *pString=reinterpret_cast<const char16_t *>(pe);
+
+                /* return the string length */
+                return full;
+            }
+        }
+
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_GET_TYPE(props)==UCASE_LOWER) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe2, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        if(!upperNotTitle && HAS_SLOT(excWord, UCASE_EXC_TITLE)) {
+            idx=UCASE_EXC_TITLE;
+        } else if(HAS_SLOT(excWord, UCASE_EXC_UPPER)) {
+            /* here, titlecase is same as uppercase */
+            idx=UCASE_EXC_UPPER;
+        } else {
+            return ~c;
+        }
+        GET_SLOT_VALUE(excWord, idx, pe2, result);
+    }
+
+    return (result==c) ? ~result : result;
+}
+
+U_CAPI int32_t U_EXPORT2
+ucase_toFullUpper(UChar32 c,
+                  UCaseContextIterator *iter, void *context,
+                  const char16_t **pString,
+                  int32_t caseLocale) {
+    return toUpperOrTitle(c, iter, context, pString, caseLocale, true);
+}
+
+U_CAPI int32_t U_EXPORT2
+ucase_toFullTitle(UChar32 c,
+                  UCaseContextIterator *iter, void *context,
+                  const char16_t **pString,
+                  int32_t caseLocale) {
+    return toUpperOrTitle(c, iter, context, pString, caseLocale, false);
+}
+
+/* case folding ------------------------------------------------------------- */
+
+/*
+ * Case folding is similar to lowercasing.
+ * The result may be a simple mapping, i.e., a single code point, or
+ * a full mapping, i.e., a string.
+ * If the case folding for a code point is the same as its simple (1:1) lowercase mapping,
+ * then only the lowercase mapping is stored.
+ *
+ * Some special cases are hardcoded because their conditions cannot be
+ * parsed and processed from CaseFolding.txt.
+ *
+ * Unicode 3.2 CaseFolding.txt specifies for its status field:
+
+# C: common case folding, common mappings shared by both simple and full mappings.
+# F: full case folding, mappings that cause strings to grow in length. Multiple characters are separated by spaces.
+# S: simple case folding, mappings to single characters where different from F.
+# T: special case for uppercase I and dotted uppercase I
+#    - For non-Turkic languages, this mapping is normally not used.
+#    - For Turkic languages (tr, az), this mapping can be used instead of the normal mapping for these characters.
+#
+# Usage:
+#  A. To do a simple case folding, use the mappings with status C + S.
+#  B. To do a full case folding, use the mappings with status C + F.
+#
+#    The mappings with status T can be used or omitted depending on the desired case-folding
+#    behavior. (The default option is to exclude them.)
+
+ * Unicode 3.2 has 'T' mappings as follows:
+
+0049; T; 0131; # LATIN CAPITAL LETTER I
+0130; T; 0069; # LATIN CAPITAL LETTER I WITH DOT ABOVE
+
+ * while the default mappings for these code points are:
+
+0049; C; 0069; # LATIN CAPITAL LETTER I
+0130; F; 0069 0307; # LATIN CAPITAL LETTER I WITH DOT ABOVE
+
+ * U+0130 has no simple case folding (simple-case-folds to itself).
+ */
+
+/* return the simple case folding mapping for c */
+U_CAPI UChar32 U_EXPORT2
+ucase_fold(UChar32 c, uint32_t options) {
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_IS_UPPER_OR_TITLE(props)) {
+            c+=UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props);
+        uint16_t excWord=*pe++;
+        int32_t idx;
+        if(excWord&UCASE_EXC_CONDITIONAL_FOLD) {
+            /* special case folding mappings, hardcoded */
+            if((options&_FOLD_CASE_OPTIONS_MASK)==U_FOLD_CASE_DEFAULT) {
+                /* default mappings */
+                if(c==0x49) {
+                    /* 0049; C; 0069; # LATIN CAPITAL LETTER I */
+                    return 0x69;
+                } else if(c==0x130) {
+                    /* no simple case folding for U+0130 */
+                    return c;
+                }
+            } else {
+                /* Turkic mappings */
+                if(c==0x49) {
+                    /* 0049; T; 0131; # LATIN CAPITAL LETTER I */
+                    return 0x131;
+                } else if(c==0x130) {
+                    /* 0130; T; 0069; # LATIN CAPITAL LETTER I WITH DOT ABOVE */
+                    return 0x69;
+                }
+            }
+        }
+        if((excWord&UCASE_EXC_NO_SIMPLE_CASE_FOLDING)!=0) {
+            return c;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_IS_UPPER_OR_TITLE(props)) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_FOLD)) {
+            idx=UCASE_EXC_FOLD;
+        } else if(HAS_SLOT(excWord, UCASE_EXC_LOWER)) {
+            idx=UCASE_EXC_LOWER;
+        } else {
+            return c;
+        }
+        GET_SLOT_VALUE(excWord, idx, pe, c);
+    }
+    return c;
+}
+
+/*
+ * Issue for canonical caseless match (UAX #21):
+ * Turkic casefolding (using "T" mappings in CaseFolding.txt) does not preserve
+ * canonical equivalence, unlike default-option casefolding.
+ * For example, I-grave and I + grave fold to strings that are not canonically
+ * equivalent.
+ * For more details, see the comment in unorm_compare() in unorm.cpp
+ * and the intermediate prototype changes for Jitterbug 2021.
+ * (For example, revision 1.104 of uchar.c and 1.4 of CaseFolding.txt.)
+ *
+ * This did not get fixed because it appears that it is not possible to fix
+ * it for uppercase and lowercase characters (I-grave vs. i-grave)
+ * together in a way that they still fold to common result strings.
+ */
+
+U_CAPI int32_t U_EXPORT2
+ucase_toFullFolding(UChar32 c,
+                    const char16_t **pString,
+                    uint32_t options) {
+    // The sign of the result has meaning, input must be non-negative so that it can be returned as is.
+    U_ASSERT(c >= 0);
+    UChar32 result=c;
+    // Reset the output pointer in case it was uninitialized.
+    *pString=nullptr;
+    uint16_t props=UTRIE2_GET16(&ucase_props_singleton.trie, c);
+    if(!UCASE_HAS_EXCEPTION(props)) {
+        if(UCASE_IS_UPPER_OR_TITLE(props)) {
+            result=c+UCASE_GET_DELTA(props);
+        }
+    } else {
+        const uint16_t *pe=GET_EXCEPTIONS(&ucase_props_singleton, props), *pe2;
+        uint16_t excWord=*pe++;
+        int32_t full, idx;
+
+        pe2=pe;
+
+        if(excWord&UCASE_EXC_CONDITIONAL_FOLD) {
+            /* use hardcoded conditions and mappings */
+            if((options&_FOLD_CASE_OPTIONS_MASK)==U_FOLD_CASE_DEFAULT) {
+                /* default mappings */
+                if(c==0x49) {
+                    /* 0049; C; 0069; # LATIN CAPITAL LETTER I */
+                    return 0x69;
+                } else if(c==0x130) {
+                    /* 0130; F; 0069 0307; # LATIN CAPITAL LETTER I WITH DOT ABOVE */
+                    *pString=iDot;
+                    return 2;
+                }
+            } else {
+                /* Turkic mappings */
+                if(c==0x49) {
+                    /* 0049; T; 0131; # LATIN CAPITAL LETTER I */
+                    return 0x131;
+                } else if(c==0x130) {
+                    /* 0130; T; 0069; # LATIN CAPITAL LETTER I WITH DOT ABOVE */
+                    return 0x69;
+                }
+            }
+        } else if(HAS_SLOT(excWord, UCASE_EXC_FULL_MAPPINGS)) {
+            GET_SLOT_VALUE(excWord, UCASE_EXC_FULL_MAPPINGS, pe, full);
+
+            /* start of full case mapping strings */
+            ++pe;
+
+            /* skip the lowercase result string */
+            pe+=full&UCASE_FULL_LOWER;
+            full=(full>>4)&0xf;
+
+            if(full!=0) {
+                /* set the output pointer to the result string */
+                *pString=reinterpret_cast<const char16_t *>(pe);
+
+                /* return the string length */
+                return full;
+            }
+        }
+
+        if((excWord&UCASE_EXC_NO_SIMPLE_CASE_FOLDING)!=0) {
+            return ~c;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_DELTA) && UCASE_IS_UPPER_OR_TITLE(props)) {
+            int32_t delta;
+            GET_SLOT_VALUE(excWord, UCASE_EXC_DELTA, pe2, delta);
+            return (excWord&UCASE_EXC_DELTA_IS_NEGATIVE)==0 ? c+delta : c-delta;
+        }
+        if(HAS_SLOT(excWord, UCASE_EXC_FOLD)) {
+            idx=UCASE_EXC_FOLD;
+        } else if(HAS_SLOT(excWord, UCASE_EXC_LOWER)) {
+            idx=UCASE_EXC_LOWER;
+        } else {
+            return ~c;
+        }
+        GET_SLOT_VALUE(excWord, idx, pe2, result);
+    }
+
+    return (result==c) ? ~result : result;
+}
+
+/* case mapping properties API ---------------------------------------------- */
+
+/* public API (see uchar.h) */
+
+U_CAPI UBool U_EXPORT2
+u_isULowercase(UChar32 c) {
+    return (UBool)(UCASE_LOWER==ucase_getType(c));
+}
+
+U_CAPI UBool U_EXPORT2
+u_isUUppercase(UChar32 c) {
+    return (UBool)(UCASE_UPPER==ucase_getType(c));
+}
+
+/* Transforms the Unicode character to its lower case equivalent.*/
+U_CAPI UChar32 U_EXPORT2
+u_tolower(UChar32 c) {
+    return ucase_tolower(c);
+}
+
+/* Transforms the Unicode character to its upper case equivalent.*/
+U_CAPI UChar32 U_EXPORT2
+u_toupper(UChar32 c) {
+    return ucase_toupper(c);
+}
+
+/* Transforms the Unicode character to its title case equivalent.*/
+U_CAPI UChar32 U_EXPORT2
+u_totitle(UChar32 c) {
+    return ucase_totitle(c);
+}
+
+/* return the simple case folding mapping for c */
+U_CAPI UChar32 U_EXPORT2
+u_foldCase(UChar32 c, uint32_t options) {
+    return ucase_fold(c, options);
+}
+
+U_CFUNC int32_t U_EXPORT2
+ucase_hasBinaryProperty(UChar32 c, UProperty which) {
+    /* case mapping properties */
+    const char16_t *resultString;
+    switch(which) {
+    case UCHAR_LOWERCASE:
+        return (UBool)(UCASE_LOWER==ucase_getType(c));
+    case UCHAR_UPPERCASE:
+        return (UBool)(UCASE_UPPER==ucase_getType(c));
+    case UCHAR_SOFT_DOTTED:
+        return ucase_isSoftDotted(c);
+    case UCHAR_CASE_SENSITIVE:
+        return ucase_isCaseSensitive(c);
+    case UCHAR_CASED:
+        return (UBool)(UCASE_NONE!=ucase_getType(c));
+    case UCHAR_CASE_IGNORABLE:
+        return (UBool)(ucase_getTypeOrIgnorable(c)>>2);
+    /*
+     * Note: The following Changes_When_Xyz are defined as testing whether
+     * the NFD form of the input changes when Xyz-case-mapped.
+     * However, this simpler implementation of these properties,
+     * ignoring NFD, passes the tests.
+     * The implementation needs to be changed if the tests start failing.
+     * When that happens, optimizations should be used to work with the
+     * per-single-code point ucase_toFullXyz() functions unless
+     * the NFD form has more than one code point,
+     * and the property starts set needs to be the union of the
+     * start sets for normalization and case mappings.
+     */
+    case UCHAR_CHANGES_WHEN_LOWERCASED:
+        return (UBool)(ucase_toFullLower(c, nullptr, nullptr, &resultString, UCASE_LOC_ROOT)>=0);
+    case UCHAR_CHANGES_WHEN_UPPERCASED:
+        return (UBool)(ucase_toFullUpper(c, nullptr, nullptr, &resultString, UCASE_LOC_ROOT)>=0);
+    case UCHAR_CHANGES_WHEN_TITLECASED:
+        return (UBool)(ucase_toFullTitle(c, nullptr, nullptr, &resultString, UCASE_LOC_ROOT)>=0);
+    /* case UCHAR_CHANGES_WHEN_CASEFOLDED: -- in uprops.c */
+    case UCHAR_CHANGES_WHEN_CASEMAPPED:
+        return (UBool)(
+            ucase_toFullLower(c, nullptr, nullptr, &resultString, UCASE_LOC_ROOT)>=0 ||
+            ucase_toFullUpper(c, nullptr, nullptr, &resultString, UCASE_LOC_ROOT)>=0 ||
+            ucase_toFullTitle(c, nullptr, nullptr, &resultString, UCASE_LOC_ROOT)>=0);
+    default:
+        return false;
+    }
+}