private static final int COMPARE_EQUIV=0x80000;
/* internal function; package visibility for use by UTF16.StringComparator */
/*package*/ static int cmpEquivFold(CharSequence cs1, CharSequence cs2, int options) {
Normalizer2Impl nfcImpl;
UCaseProps csp;
/* current-level start/limit - s1/s2 as current */
int s1, s2, limit1, limit2;
/* decomposition and case folding variables */
int length;
/* stacks of previous-level start/current/limit */
CmpEquivLevel[] stack1=null, stack2=null;
/* buffers for algorithmic decompositions */
String decomp1, decomp2;
/* case folding buffers, only use current-level start/limit */
StringBuffer fold1, fold2;
/* track which is the current level per string */
int level1, level2;
/* current code units, and code points for lookups */
int c1, c2, cp1, cp2;
/* no argument error checking because this itself is not an API */
/*
* assume that at least one of the options _COMPARE_EQUIV and U_COMPARE_IGNORE_CASE is set
* otherwise this function must behave exactly as uprv_strCompare()
* not checking for that here makes testing this function easier
*/
/* normalization/properties data loaded? */
if((options&COMPARE_EQUIV)!=0) {
nfcImpl=Norm2AllModes.getNFCInstance().impl;
} else {
nfcImpl=null;
}
if((options&COMPARE_IGNORE_CASE)!=0) {
try {
csp=UCaseProps.getSingleton();
} catch(IOException e) {
throw new RuntimeException(e);
}
fold1=new StringBuffer();
fold2=new StringBuffer();
} else {
csp=null;
fold1=fold2=null;
}
/* initialize */
s1=0;
limit1=cs1.length();
s2=0;
limit2=cs2.length();
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) {
if(level1==0) {
c1=-1;
break;
}
} else {
c1=cs1.charAt(s1++);
break;
}
/* reached end of level buffer, pop one level */
do {
--level1;
cs1=stack1[level1].cs;
} while(cs1==null);
s1=stack1[level1].s;
limit1=cs1.length();
}
}
if(c2<0) {
/* get next code unit from string 2, post-increment */
for(;;) {
if(s2==limit2) {
if(level2==0) {
c2=-1;
break;
}
} else {
c2=cs2.charAt(s2++);
break;
}
/* reached end of level buffer, pop one level */
do {
--level2;
cs2=stack2[level2].cs;
} while(cs2==null);
s2=stack2[level2].s;
limit2=cs2.length();
}
}
/*
* 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(UTF16.isSurrogate((char)c1)) {
char c;
if(Normalizer2Impl.UTF16Plus.isSurrogateLead(c1)) {
if(s1!=limit1 && Character.isLowSurrogate(c=cs1.charAt(s1))) {
/* advance ++s1; only below if cp1 decomposes/case-folds */
cp1=Character.toCodePoint((char)c1, c);
}
} else /* isTrail(c1) */ {
if(0<=(s1-2) && Character.isHighSurrogate(c=cs1.charAt(s1-2))) {
cp1=Character.toCodePoint(c, (char)c1);
}
}
}
cp2=c2;
if(UTF16.isSurrogate((char)c2)) {
char c;
if(Normalizer2Impl.UTF16Plus.isSurrogateLead(c2)) {
if(s2!=limit2 && Character.isLowSurrogate(c=cs2.charAt(s2))) {
/* advance ++s2; only below if cp2 decomposes/case-folds */
cp2=Character.toCodePoint((char)c2, c);
}
} else /* isTrail(c2) */ {
if(0<=(s2-2) && Character.isHighSurrogate(c=cs2.charAt(s2-2))) {
cp2=Character.toCodePoint(c, (char)c2);
}
}
}
/*
* go down one level for each string
* continue with the main loop as soon as there is a real change
*/
if( level1==0 && (options&COMPARE_IGNORE_CASE)!=0 &&
(length=csp.toFullFolding(cp1, fold1, options))>=0
) {
/* cp1 case-folds to the code point "length" or to p[length] */
if(UTF16.isSurrogate((char)c1)) {
if(Normalizer2Impl.UTF16Plus.isSurrogateLead(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=cs2.charAt(s2-1);
}
}
/* push current level pointers */
if(stack1==null) {
stack1=createCmpEquivLevelStack();
}
stack1[0].cs=cs1;
stack1[0].s=s1;
++level1;
/* copy the folding result to fold1[] */
/* Java: the buffer was probably not empty, remove the old contents */
if(length<=UCaseProps.MAX_STRING_LENGTH) {
fold1.delete(0, fold1.length()-length);
} else {
fold1.setLength(0);
fold1.appendCodePoint(length);
}
/* set next level pointers to case folding */
cs1=fold1;
s1=0;
limit1=fold1.length();
/* get ready to read from decomposition, continue with loop */
c1=-1;
continue;
}
if( level2==0 && (options&COMPARE_IGNORE_CASE)!=0 &&
(length=csp.toFullFolding(cp2, fold2, options))>=0
) {
/* cp2 case-folds to the code point "length" or to p[length] */
if(UTF16.isSurrogate((char)c2)) {
if(Normalizer2Impl.UTF16Plus.isSurrogateLead(c2)) {
/* advance beyond source surrogate pair if it case-folds */