/*
*******************************************************************************
*
* Copyright (C) 2001-2010, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: ustrcase.c
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2002feb20
* created by: Markus W. Scherer
*
* Implementation file for string casing C API functions.
* Uses functions from uchar.c for basic functionality that requires access
* to the Unicode Character Database (uprops.dat).
*/
#include "unicode/utypes.h"
#include "unicode/uloc.h"
#include "unicode/ustring.h"
#include "unicode/ucasemap.h"
#include "unicode/ubrk.h"
#include "cmemory.h"
#include "ucase.h"
#include "ustr_imp.h"
/* string casing ------------------------------------------------------------ */
/* append a full case mapping result, see UCASE_MAX_STRING_LENGTH */
static U_INLINE int32_t
appendResult(UChar *dest, int32_t destIndex, int32_t destCapacity,
int32_t result, const UChar *s) {
UChar32 c;
int32_t length;
/* decode the result */
if(result<0) {
/* (not) original code point */
c=~result;
length=-1;
} else if(result<=UCASE_MAX_STRING_LENGTH) {
c=U_SENTINEL;
length=result;
} else {
c=result;
length=-1;
}
if(destIndex<destCapacity) {
/* append the result */
if(length<0) {
/* code point */
UBool isError=FALSE;
U16_APPEND(dest, destIndex, destCapacity, c, isError);
if(isError) {
/* overflow, nothing written */
destIndex+=U16_LENGTH(c);
}
} else {
/* string */
if((destIndex+length)<=destCapacity) {
while(length>0) {
dest[destIndex++]=*s++;
--length;
}
} else {
/* overflow */
destIndex+=length;
}
}
} else {
/* preflight */
if(length<0) {
destIndex+=U16_LENGTH(c);
} else {
destIndex+=length;
}
}
return destIndex;
}
static UChar32 U_CALLCONV
utf16_caseContextIterator(void *context, int8_t dir) {
UCaseContext *csc=(UCaseContext *)context;
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;
}
if(dir<0) {
if(csc->start<csc->index) {
U16_PREV((const UChar *)csc->p, csc->start, csc->index, c);
return c;
}
} else {
if(csc->index<csc->limit) {
U16_NEXT((const UChar *)csc->p, csc->index, csc->limit, c);
return c;
}
}
return U_SENTINEL;
}
/*
* Case-maps [srcStart..srcLimit[ but takes
* context [0..srcLength[ into account.
*/
static int32_t
_caseMap(const UCaseMap *csm, UCaseMapFull *map,
UChar *dest, int32_t destCapacity,
const UChar *src, UCaseContext *csc,
int32_t srcStart, int32_t srcLimit,
UErrorCode *pErrorCode) {
const UChar *s;
UChar32 c, c2 = 0;
int32_t srcIndex, destIndex;
int32_t locCache;
locCache=csm->locCache;
/* case mapping loop */
srcIndex=srcStart;
destIndex=0;
while(srcIndex<srcLimit) {
csc->cpStart=srcIndex;
U16_NEXT(src, srcIndex, srcLimit, c);
csc->cpLimit=srcIndex;
c=map(csm->csp, c, utf16_caseContextIterator, csc, &s, csm->locale, &locCache);
if((destIndex<destCapacity) && (c<0 ? (c2=~c)<=0xffff : UCASE_MAX_STRING_LENGTH<c && (c2=c)<=0xffff)) {
/* fast path version of appendResult() for BMP results */
dest[destIndex++]=(UChar)c2;
} else {
destIndex=appendResult(dest, destIndex, destCapacity, c, s);
}
}
if(destIndex>destCapacity) {
*pErrorCode=U_BUFFER_OVERFLOW_ERROR;
}
return destIndex;
}
static void
setTempCaseMapLocale(UCaseMap *csm, const char *locale, UErrorCode *pErrorCode) {
/*
* We could call ucasemap_setLocale(), but here we really only care about
* the initial language subtag, we need not return the real string via
* ucasemap_getLocale(), and we don't care about only getting "x" from
* "x-some-thing" etc.
*
* We ignore locales with a longer-than-3 initial subtag.
*
* We also do not fill in the locCache because it is rarely used,
* and not worth setting unless we reuse it for many case mapping operations.
* (That's why UCaseMap was created.)
*/
int i;
char c;
/* the internal functions require locale!=NULL */
if(locale==NULL) {
locale=uloc_getDefault();
}
for(i=0; i<4 && (c=locale[i])!=0 && c!='-' && c!='_'; ++i) {
csm->locale[i]=c;
}
if(i<=3) {
csm->locale[i]=0; /* Up to 3 non-separator characters. */
} else {
csm->locale[0]=0; /* Longer-than-3 initial subtag: Ignore. */
}
}
/*
* Set parameters on an empty UCaseMap, for UCaseMap-less API functions.
* Do this fast because it is called with every function call.
*/
static U_INLINE void
setTempCaseMap(UCaseMap *csm, const char *locale, UErrorCode *pErrorCode) {
if(csm->csp==NULL) {
csm->csp=ucase_getSingleton();
}
if(locale!=NULL && locale[0]==0) {
csm->locale[0]=0;
} else {
setTempCaseMapLocale(csm, locale, pErrorCode);
}
}
#if !UCONFIG_NO_BREAK_ITERATION
/*
* Internal titlecasing function.
*/
static int32_t
_toTitle(UCaseMap *csm,
UChar *dest, int32_t destCapacity,
const UChar *src, UCaseContext *csc,
int32_t srcLength,
UErrorCode *pErrorCode) {
const UChar *s;
UChar32 c;
int32_t prev, titleStart, titleLimit, idx, destIndex, length;
UBool isFirstIndex;
if(csm->iter!=NULL) {
ubrk_setText(csm->iter, src, srcLength, pErrorCode);
} else {
csm->iter=ubrk_open(UBRK_WORD, csm->locale,
src, srcLength,
pErrorCode);
}
if(U_FAILURE(*pErrorCode)) {
return 0;
}
/* set up local variables */
destIndex=0;
prev=0;
isFirstIndex=TRUE;
/* titlecasing loop */
while(prev<srcLength) {
/* find next index where to titlecase */
if(isFirstIndex) {
isFirstIndex=FALSE;
idx=ubrk_first(csm->iter);
} else {
idx=ubrk_next(csm->iter);
}
if(idx==UBRK_DONE || idx>srcLength) {
idx=srcLength;
}
/*
* Unicode 4 & 5 section 3.13 Default Case Operations:
*
* R3 toTitlecase(X): Find the word boundaries based on Unicode Standard Annex
* #29, "Text Boundaries." Between each pair of word boundaries, find the first
* cased character F. If F exists, map F to default_title(F); then map each
* subsequent character C to default_lower(C).
*
* In this implementation, segment [prev..index[ into 3 parts:
* a) uncased characters (copy as-is) [prev..titleStart[
* b) first case letter (titlecase) [titleStart..titleLimit[
* c) subsequent characters (lowercase) [titleLimit..index[
*/
if(prev<idx) {
/* find and copy uncased characters [prev..titleStart[ */
titleStart=titleLimit=prev;
U16_NEXT(src, titleLimit, idx, c);
if((csm->options&U_TITLECASE_NO_BREAK_ADJUSTMENT)==0 && UCASE_NONE==ucase_getType(csm->csp, c)) {
/* Adjust the titlecasing index (titleStart) to the next cased character. */
for(;;) {
titleStart=titleLimit;
if(titleLimit==idx) {
/*
* only uncased characters in [prev..index[
* stop with titleStart==titleLimit==index
*/
break;
}
U16_NEXT(src, titleLimit, idx, c);
if(UCASE_NONE!=ucase_getType(csm->csp, c)) {
break; /* cased letter at [titleStart..titleLimit[ */
}
}
length=titleStart-prev;
if(length>0) {
if((destIndex+length)<=destCapacity) {
uprv_memcpy(dest+destIndex, src+prev, length*U_SIZEOF_UCHAR);
}
destIndex+=length;
}
}
if(titleStart<titleLimit) {
/* titlecase c which is from [titleStart..titleLimit[ */
csc->cpStart=titleStart;
csc->cpLimit=titleLimit;
c=ucase_toFullTitle(csm->csp, c, utf16_caseContextIterator, csc, &s, csm->locale, &csm->locCache);
destIndex=appendResult(dest, destIndex, destCapacity, c, s);
/* Special case Dutch IJ titlecasing */
if ( titleStart+1 < idx &&
ucase_getCaseLocale(csm->locale,&csm->locCache) == UCASE_LOC_DUTCH &&
( src[titleStart] == (UChar32) 0x0049 || src[titleStart] == (UChar32) 0x0069 ) &&
( src[titleStart+1] == (UChar32) 0x004A || src[titleStart+1] == (UChar32) 0x006A )) {
c=(UChar32) 0x004A;
destIndex=appendResult(dest, destIndex, destCapacity, c, s);
titleLimit++;
}
/* lowercase [titleLimit..index[ */
if(titleLimit<idx) {
if((csm->options&U_TITLECASE_NO_LOWERCASE)==0) {
/* Normal operation: Lowercase the rest of the word. */
destIndex+=
_caseMap(
csm, ucase_toFullLower,
dest+destIndex, destCapacity-destIndex,
src, csc,
titleLimit, idx,
pErrorCode);
} else {
/* Optionally just copy the rest of the word unchanged. */
length=idx-titleLimit;
if((destIndex+length)<=destCapacity) {
uprv_memcpy(dest+destIndex, src+titleLimit, length*U_SIZEOF_UCHAR);
}
destIndex+=length;
}
}
}
}
prev=idx;
}
if(destIndex>destCapacity) {
*pErrorCode=U_BUFFER_OVERFLOW_ERROR;
}
return destIndex;
}
#endif
/* functions available in the common library (for unistr_case.cpp) */
U_CFUNC int32_t
ustr_toLower(const UCaseProps *csp,
UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
const char *locale,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
UCaseContext csc={ NULL };
csm.csp=csp;
setTempCaseMap(&csm, locale, pErrorCode);
csc.p=(void *)src;
csc.limit=srcLength;
return _caseMap(&csm, ucase_toFullLower,
dest, destCapacity,
src, &csc, 0, srcLength,
pErrorCode);
}
U_CFUNC int32_t
ustr_toUpper(const UCaseProps *csp,
UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
const char *locale,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
UCaseContext csc={ NULL };
csm.csp=csp;
setTempCaseMap(&csm, locale, pErrorCode);
csc.p=(void *)src;
csc.limit=srcLength;
return _caseMap(&csm, ucase_toFullUpper,
dest, destCapacity,
src, &csc, 0, srcLength,
pErrorCode);
}
#if !UCONFIG_NO_BREAK_ITERATION
U_CFUNC int32_t
ustr_toTitle(const UCaseProps *csp,
UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
UBreakIterator *titleIter,
const char *locale, uint32_t options,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
UCaseContext csc={ NULL };
int32_t length;
csm.csp=csp;
csm.iter=titleIter;
csm.options=options;
setTempCaseMap(&csm, locale, pErrorCode);
csc.p=(void *)src;
csc.limit=srcLength;
length=_toTitle(&csm,
dest, destCapacity,
src, &csc, srcLength,
pErrorCode);
if(titleIter==NULL && csm.iter!=NULL) {
ubrk_close(csm.iter);
}
return length;
}
#endif
U_CFUNC int32_t
ustr_foldCase(const UCaseProps *csp,
UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
uint32_t options,
UErrorCode *pErrorCode) {
int32_t srcIndex, destIndex;
const UChar *s;
UChar32 c, c2 = 0;
/* case mapping loop */
srcIndex=destIndex=0;
while(srcIndex<srcLength) {
U16_NEXT(src, srcIndex, srcLength, c);
c=ucase_toFullFolding(csp, c, &s, options);
if((destIndex<destCapacity) && (c<0 ? (c2=~c)<=0xffff : UCASE_MAX_STRING_LENGTH<c && (c2=c)<=0xffff)) {
/* fast path version of appendResult() for BMP results */
dest[destIndex++]=(UChar)c2;
} else {
destIndex=appendResult(dest, destIndex, destCapacity, c, s);
}
}
if(destIndex>destCapacity) {
*pErrorCode=U_BUFFER_OVERFLOW_ERROR;
}
return destIndex;
}
/*
* Implement argument checking and buffer handling
* for string case mapping as a common function.
*/
/* common internal function for public API functions */
static int32_t
caseMap(const UCaseMap *csm,
UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
int32_t toWhichCase,
UErrorCode *pErrorCode) {
UChar buffer[300];
UChar *temp;
int32_t destLength;
/* check argument values */
if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
return 0;
}
if( destCapacity<0 ||
(dest==NULL && destCapacity>0) ||
src==NULL ||
srcLength<-1
) {
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
/* get the string length */
if(srcLength==-1) {
srcLength=u_strlen(src);
}
/* check for overlapping source and destination */
if( dest!=NULL &&
((src>=dest && src<(dest+destCapacity)) ||
(dest>=src && dest<(src+srcLength)))
) {
/* overlap: provide a temporary destination buffer and later copy the result */
if(destCapacity<=(sizeof(buffer)/U_SIZEOF_UCHAR)) {
/* the stack buffer is large enough */
temp=buffer;
} else {
/* allocate a buffer */
temp=(UChar *)uprv_malloc(destCapacity*U_SIZEOF_UCHAR);
if(temp==NULL) {
*pErrorCode=U_MEMORY_ALLOCATION_ERROR;
return 0;
}
}
} else {
temp=dest;
}
destLength=0;
if(toWhichCase==FOLD_CASE) {
destLength=ustr_foldCase(csm->csp, temp, destCapacity, src, srcLength,
csm->options, pErrorCode);
} else {
UCaseContext csc={ NULL };
csc.p=(void *)src;
csc.limit=srcLength;
if(toWhichCase==TO_LOWER) {
destLength=_caseMap(csm, ucase_toFullLower,
temp, destCapacity,
src, &csc,
0, srcLength,
pErrorCode);
} else if(toWhichCase==TO_UPPER) {
destLength=_caseMap(csm, ucase_toFullUpper,
temp, destCapacity,
src, &csc,
0, srcLength,
pErrorCode);
} else /* if(toWhichCase==TO_TITLE) */ {
#if UCONFIG_NO_BREAK_ITERATION
*pErrorCode=U_UNSUPPORTED_ERROR;
#else
/* UCaseMap is actually non-const in toTitle() APIs. */
destLength=_toTitle((UCaseMap *)csm, temp, destCapacity,
src, &csc, srcLength,
pErrorCode);
#endif
}
}
if(temp!=dest) {
/* copy the result string to the destination buffer */
if(destLength>0) {
int32_t copyLength= destLength<=destCapacity ? destLength : destCapacity;
if(copyLength>0) {
uprv_memmove(dest, temp, copyLength*U_SIZEOF_UCHAR);
}
}
if(temp!=buffer) {
uprv_free(temp);
}
}
return u_terminateUChars(dest, destCapacity, destLength, pErrorCode);
}
/* public API functions */
U_CAPI int32_t U_EXPORT2
u_strToLower(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
const char *locale,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
setTempCaseMap(&csm, locale, pErrorCode);
return caseMap(&csm,
dest, destCapacity,
src, srcLength,
TO_LOWER, pErrorCode);
}
U_CAPI int32_t U_EXPORT2
u_strToUpper(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
const char *locale,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
setTempCaseMap(&csm, locale, pErrorCode);
return caseMap(&csm,
dest, destCapacity,
src, srcLength,
TO_UPPER, pErrorCode);
}
#if !UCONFIG_NO_BREAK_ITERATION
U_CAPI int32_t U_EXPORT2
u_strToTitle(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
UBreakIterator *titleIter,
const char *locale,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
int32_t length;
csm.iter=titleIter;
setTempCaseMap(&csm, locale, pErrorCode);
length=caseMap(&csm,
dest, destCapacity,
src, srcLength,
TO_TITLE, pErrorCode);
if(titleIter==NULL && csm.iter!=NULL) {
ubrk_close(csm.iter);
}
return length;
}
U_CAPI int32_t U_EXPORT2
ucasemap_toTitle(UCaseMap *csm,
UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
UErrorCode *pErrorCode) {
return caseMap(csm,
dest, destCapacity,
src, srcLength,
TO_TITLE, pErrorCode);
}
#endif
U_CAPI int32_t U_EXPORT2
u_strFoldCase(UChar *dest, int32_t destCapacity,
const UChar *src, int32_t srcLength,
uint32_t options,
UErrorCode *pErrorCode) {
UCaseMap csm={ NULL };
csm.csp=ucase_getSingleton();
csm.options=options;
return caseMap(&csm,
dest, destCapacity,
src, srcLength,
FOLD_CASE, pErrorCode);
}
/* case-insensitive string comparisons -------------------------------------- */
/*
* This function is a copy of unorm_cmpEquivFold() minus the parts for
* canonical equivalence.
* Keep the functions in sync, and see there for how this works.
* The duplication is for modularization:
* It makes caseless (but not canonical caseless) matches independent of
* the normalization code.
*/
/* stack element for previous-level source/decomposition pointers */
struct CmpEquivLevel {
const UChar *start, *s, *limit;
};
typedef struct CmpEquivLevel CmpEquivLevel;
/* internal function */
U_CFUNC int32_t
u_strcmpFold(const UChar *s1, int32_t length1,
const UChar *s2, int32_t length2,
uint32_t options,
UErrorCode *pErrorCode) {
const UCaseProps *csp;
/* current-level start/limit - s1/s2 as current */
const UChar *start1, *start2, *limit1, *limit2;
/* case folding variables */
const UChar *p;
int32_t length;
/* stacks of previous-level start/current/limit */
CmpEquivLevel stack1[2], stack2[2];
/* case folding buffers, only use current-level start/limit */
UChar fold1[UCASE_MAX_STRING_LENGTH+1], fold2[UCASE_MAX_STRING_LENGTH+1];
/* track which is the current level per string */
int32_t level1, level2;
/* current code units, and code points for lookups */
UChar32 c1, c2, cp1, cp2;
/* no argument error checking because this itself is not an API */
/*
* assume that at least the option U_COMPARE_IGNORE_CASE is set
* otherwise this function would have to behave exactly as uprv_strCompare()
*/
csp=ucase_getSingleton();
if(U_FAILURE(*pErrorCode)) {
return 0;
}
/* initialize */
start1=s1;
if(length1==-1) {
limit1=NULL;
} else {
limit1=s1+length1;
}
start2=s2;
if(length2==-1) {
limit2=NULL;
} else {
limit2=s2+length2;
}
level1=level2=0;
c1=c2=-1;
/* comparison loop */
for(;;) {
/*
* here a code unit value of -1 means "get another code unit"
* below it will mean "this source is finished"
*/
if(c1<0) {
/* get next code unit from string 1, post-increment */
for(;;) {
if(s1==limit1 || ((c1=*s1)==0 && (limit1==NULL || (options&_STRNCMP_STYLE)))) {
if(level1==0) {
c1=-1;
break;
}
} else {
++s1;
break;
}
/* reached end of level buffer, pop one level */
do {
--level1;
start1=stack1[level1].start;
} while(start1==NULL);
s1=stack1[level1].s;
limit1=stack1[level1].limit;
}
}
if(c2<0) {
/* get next code unit from string 2, post-increment */
for(;;) {
if(s2==limit2 || ((c2=*s2)==0 && (limit2==NULL || (options&_STRNCMP_STYLE)))) {
if(level2==0) {
c2=-1;
break;
}
} else {
++s2;
break;
}
/* reached end of level buffer, pop one level */
do {
--level2;
start2=stack2[level2].start;
} while(start2==NULL);
s2=stack2[level2].s;
limit2=stack2[level2].limit;
}
}
/*
* compare c1 and c2
* either variable c1, c2 is -1 only if the corresponding string is finished
*/
if(c1==c2) {
if(c1<0) {
return 0; /* c1==c2==-1 indicating end of strings */
}
c1=c2=-1; /* make us fetch new code units */
continue;
} else if(c1<0) {
return -1; /* string 1 ends before string 2 */
} else if(c2<0) {
return 1; /* string 2 ends before string 1 */
}
/* c1!=c2 && c1>=0 && c2>=0 */
/* get complete code points for c1, c2 for lookups if either is a surrogate */
cp1=c1;
if(U_IS_SURROGATE(c1)) {
UChar c;
if(U_IS_SURROGATE_LEAD(c1)) {
if(s1!=limit1 && U16_IS_TRAIL(c=*s1)) {
/* advance ++s1; only below if cp1 decomposes/case-folds */
cp1=U16_GET_SUPPLEMENTARY(c1, c);
}
} else /* isTrail(c1) */ {
if(start1<=(s1-2) && U16_IS_LEAD(c=*(s1-2))) {
cp1=U16_GET_SUPPLEMENTARY(c, c1);
}
}
}
cp2=c2;
if(U_IS_SURROGATE(c2)) {
UChar c;
if(U_IS_SURROGATE_LEAD(c2)) {
if(s2!=limit2 && U16_IS_TRAIL(c=*s2)) {
/* advance ++s2; only below if cp2 decomposes/case-folds */
cp2=U16_GET_SUPPLEMENTARY(c2, c);
}
} else /* isTrail(c2) */ {
if(start2<=(s2-2) && U16_IS_LEAD(c=*(s2-2))) {
cp2=U16_GET_SUPPLEMENTARY(c, c2);
}
}
}
/*
* go down one level for each string
* continue with the main loop as soon as there is a real change
*/
if( level1==0 &&
(length=ucase_toFullFolding(csp, (UChar32)cp1, &p, options))>=0
) {
/* cp1 case-folds to the code point "length" or to p[length] */
if(U_IS_SURROGATE(c1)) {
if(U_IS_SURROGATE_LEAD(c1)) {
/* advance beyond source surrogate pair if it case-folds */
++s1;
} else /* isTrail(c1) */ {
/*
* we got a supplementary code point when hitting its trail surrogate,
* therefore the lead surrogate must have been the same as in the other string;
* compare this decomposition with the lead surrogate in the other string
* remember that this simulates bulk text replacement:
* the decomposition would replace the entire code point
*/
--s2;
c2=*(s2-1);
}
}
/* push current level pointers */
stack1[0].start=start1;
stack1[0].s=s1;
stack1[0].limit=limit1;
++level1;
/* copy the folding result to fold1[] */
if(length<=UCASE_MAX_STRING_LENGTH) {
u_memcpy(fold1, p, length);
} else {
int32_t i=0;
U16_APPEND_UNSAFE(fold1, i, length);
length=i;
}
/* set next level pointers to case folding */
start1=s1=fold1;
limit1=fold1+length;
/* get ready to read from decomposition, continue with loop */
c1=-1;
continue;
}
if( level2==0 &&
(length=ucase_toFullFolding(csp, (UChar32)cp2, &p, options))>=0
) {
/* cp2 case-folds to the code point "length" or to p[length] */
if(U_IS_SURROGATE(c2)) {
if(U_IS_SURROGATE_LEAD(c2)) {
/* advance beyond source surrogate pair if it case-folds */
++s2;
} else /* isTrail(c2) */ {
/*
* we got a supplementary code point when hitting its trail surrogate,
* therefore the lead surrogate must have been the same as in the other string;
* compare this decomposition with the lead surrogate in the other string
* remember that this simulates bulk text replacement:
* the decomposition would replace the entire code point
*/
--s1;
c1=*(s1-1);
}
}
/* push current level pointers */
stack2[0].start=start2;
stack2[0].s=s2;
stack2[0].limit=limit2;
++level2;
/* copy the folding result to fold2[] */
if(length<=UCASE_MAX_STRING_LENGTH) {
u_memcpy(fold2, p, length);
} else {
int32_t i=0;
U16_APPEND_UNSAFE(fold2, i, length);
length=i;
}
/* set next level pointers to case folding */
start2=s2=fold2;
limit2=fold2+length;
/* get ready to read from decomposition, continue with loop */
c2=-1;
continue;
}
/*
* no decomposition/case folding, max level for both sides:
* return difference result
*
* code point order comparison must not just return cp1-cp2
* because when single surrogates are present then the surrogate pairs
* that formed cp1 and cp2 may be from different string indexes
*
* example: { d800 d800 dc01 } vs. { d800 dc00 }, compare at second code units
* c1=d800 cp1=10001 c2=dc00 cp2=10000
* cp1-cp2>0 but c1-c2<0 and in fact in UTF-32 it is { d800 10001 } < { 10000 }
*
* therefore, use same fix-up as in ustring.c/uprv_strCompare()
* except: uprv_strCompare() fetches c=*s while this functions fetches c=*s++
* so we have slightly different pointer/start/limit comparisons here
*/
if(c1>=0xd800 && c2>=0xd800 && (options&U_COMPARE_CODE_POINT_ORDER)) {
/* subtract 0x2800 from BMP code points to make them smaller than supplementary ones */
if(
(c1<=0xdbff && s1!=limit1 && U16_IS_TRAIL(*s1)) ||
(U16_IS_TRAIL(c1) && start1!=(s1-1) && U16_IS_LEAD(*(s1-2)))
) {
/* part of a surrogate pair, leave >=d800 */
} else {
/* BMP code point - may be surrogate code point - make <d800 */
c1-=0x2800;
}
if(
(c2<=0xdbff && s2!=limit2 && U16_IS_TRAIL(*s2)) ||
(U16_IS_TRAIL(c2) && start2!=(s2-1) && U16_IS_LEAD(*(s2-2)))
) {
/* part of a surrogate pair, leave >=d800 */
} else {
/* BMP code point - may be surrogate code point - make <d800 */
c2-=0x2800;
}
}
return c1-c2;
}
}
/* public API functions */
U_CAPI int32_t U_EXPORT2
u_strCaseCompare(const UChar *s1, int32_t length1,
const UChar *s2, int32_t length2,
uint32_t options,
UErrorCode *pErrorCode) {
/* argument checking */
if(pErrorCode==0 || U_FAILURE(*pErrorCode)) {
return 0;
}
if(s1==NULL || length1<-1 || s2==NULL || length2<-1) {
*pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
return u_strcmpFold(s1, length1, s2, length2,
options|U_COMPARE_IGNORE_CASE,
pErrorCode);
}
U_CAPI int32_t U_EXPORT2
u_strcasecmp(const UChar *s1, const UChar *s2, uint32_t options) {
UErrorCode errorCode=U_ZERO_ERROR;
return u_strcmpFold(s1, -1, s2, -1,
options|U_COMPARE_IGNORE_CASE,
&errorCode);
}
U_CAPI int32_t U_EXPORT2
u_memcasecmp(const UChar *s1, const UChar *s2, int32_t length, uint32_t options) {
UErrorCode errorCode=U_ZERO_ERROR;
return u_strcmpFold(s1, length, s2, length,
options|U_COMPARE_IGNORE_CASE,
&errorCode);
}
U_CAPI int32_t U_EXPORT2
u_strncasecmp(const UChar *s1, const UChar *s2, int32_t n, uint32_t options) {
UErrorCode errorCode=U_ZERO_ERROR;
return u_strcmpFold(s1, n, s2, n,
options|(U_COMPARE_IGNORE_CASE|_STRNCMP_STYLE),
&errorCode);
}