scuffed-code/icu4c/source/common/bmpset.cpp

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/*
******************************************************************************
*
* Copyright (C) 2007-2011, International Business Machines
* Corporation and others. All Rights Reserved.
*
******************************************************************************
* file name: bmpset.cpp
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2007jan29
* created by: Markus W. Scherer
*/
#include "unicode/utypes.h"
#include "unicode/uniset.h"
#include "unicode/utf8.h"
#include "unicode/utf16.h"
#include "cmemory.h"
#include "bmpset.h"
U_NAMESPACE_BEGIN
BMPSet::BMPSet(const int32_t *parentList, int32_t parentListLength) :
list(parentList), listLength(parentListLength) {
uprv_memset(asciiBytes, 0, sizeof(asciiBytes));
uprv_memset(table7FF, 0, sizeof(table7FF));
uprv_memset(bmpBlockBits, 0, sizeof(bmpBlockBits));
/*
* Set the list indexes for binary searches for
* U+0800, U+1000, U+2000, .., U+F000, U+10000.
* U+0800 is the first 3-byte-UTF-8 code point. Lower code points are
* looked up in the bit tables.
* The last pair of indexes is for finding supplementary code points.
*/
list4kStarts[0]=findCodePoint(0x800, 0, listLength-1);
int32_t i;
for(i=1; i<=0x10; ++i) {
list4kStarts[i]=findCodePoint(i<<12, list4kStarts[i-1], listLength-1);
}
list4kStarts[0x11]=listLength-1;
initBits();
overrideIllegal();
}
BMPSet::BMPSet(const BMPSet &otherBMPSet, const int32_t *newParentList, int32_t newParentListLength) :
list(newParentList), listLength(newParentListLength) {
uprv_memcpy(asciiBytes, otherBMPSet.asciiBytes, sizeof(asciiBytes));
uprv_memcpy(table7FF, otherBMPSet.table7FF, sizeof(table7FF));
uprv_memcpy(bmpBlockBits, otherBMPSet.bmpBlockBits, sizeof(bmpBlockBits));
uprv_memcpy(list4kStarts, otherBMPSet.list4kStarts, sizeof(list4kStarts));
}
BMPSet::~BMPSet() {
}
/*
* Set bits in a bit rectangle in "vertical" bit organization.
* start<limit<=0x800
*/
static void set32x64Bits(uint32_t table[64], int32_t start, int32_t limit) {
int32_t lead=start>>6;
int32_t trail=start&0x3f;
// Set one bit indicating an all-one block.
uint32_t bits=(uint32_t)1<<lead;
if((start+1)==limit) { // Single-character shortcut.
table[trail]|=bits;
return;
}
int32_t limitLead=limit>>6;
int32_t limitTrail=limit&0x3f;
if(lead==limitLead) {
// Partial vertical bit column.
while(trail<limitTrail) {
table[trail++]|=bits;
}
} else {
// Partial vertical bit column,
// followed by a bit rectangle,
// followed by another partial vertical bit column.
if(trail>0) {
do {
table[trail++]|=bits;
} while(trail<64);
++lead;
}
if(lead<limitLead) {
bits=~((1<<lead)-1);
if(limitLead<0x20) {
bits&=(1<<limitLead)-1;
}
for(trail=0; trail<64; ++trail) {
table[trail]|=bits;
}
}
bits=1<<limitLead;
for(trail=0; trail<limitTrail; ++trail) {
table[trail]|=bits;
}
}
}
void BMPSet::initBits() {
UChar32 start, limit;
int32_t listIndex=0;
// Set asciiBytes[].
do {
start=list[listIndex++];
if(listIndex<listLength) {
limit=list[listIndex++];
} else {
limit=0x110000;
}
if(start>=0x80) {
break;
}
do {
asciiBytes[start++]=1;
} while(start<limit && start<0x80);
} while(limit<=0x80);
// Set table7FF[].
while(start<0x800) {
set32x64Bits(table7FF, start, limit<=0x800 ? limit : 0x800);
if(limit>0x800) {
start=0x800;
break;
}
start=list[listIndex++];
if(listIndex<listLength) {
limit=list[listIndex++];
} else {
limit=0x110000;
}
}
// Set bmpBlockBits[].
int32_t minStart=0x800;
while(start<0x10000) {
if(limit>0x10000) {
limit=0x10000;
}
if(start<minStart) {
start=minStart;
}
if(start<limit) { // Else: Another range entirely in a known mixed-value block.
if(start&0x3f) {
// Mixed-value block of 64 code points.
start>>=6;
bmpBlockBits[start&0x3f]|=0x10001<<(start>>6);
start=(start+1)<<6; // Round up to the next block boundary.
minStart=start; // Ignore further ranges in this block.
}
if(start<limit) {
if(start<(limit&~0x3f)) {
// Multiple all-ones blocks of 64 code points each.
set32x64Bits(bmpBlockBits, start>>6, limit>>6);
}
if(limit&0x3f) {
// Mixed-value block of 64 code points.
limit>>=6;
bmpBlockBits[limit&0x3f]|=0x10001<<(limit>>6);
limit=(limit+1)<<6; // Round up to the next block boundary.
minStart=limit; // Ignore further ranges in this block.
}
}
}
if(limit==0x10000) {
break;
}
start=list[listIndex++];
if(listIndex<listLength) {
limit=list[listIndex++];
} else {
limit=0x110000;
}
}
}
/*
* Override some bits and bytes to the result of contains(FFFD)
* for faster validity checking at runtime.
* No need to set 0 values where they were reset to 0 in the constructor
* and not modified by initBits().
* (asciiBytes[] trail bytes, table7FF[] 0..7F, bmpBlockBits[] 0..7FF)
* Need to set 0 values for surrogates D800..DFFF.
*/
void BMPSet::overrideIllegal() {
uint32_t bits, mask;
int32_t i;
if(containsSlow(0xfffd, list4kStarts[0xf], list4kStarts[0x10])) {
// contains(FFFD)==TRUE
for(i=0x80; i<0xc0; ++i) {
asciiBytes[i]=1;
}
bits=3; // Lead bytes 0xC0 and 0xC1.
for(i=0; i<64; ++i) {
table7FF[i]|=bits;
}
bits=1; // Lead byte 0xE0.
for(i=0; i<32; ++i) { // First half of 4k block.
bmpBlockBits[i]|=bits;
}
mask=~(0x10001<<0xd); // Lead byte 0xED.
bits=1<<0xd;
for(i=32; i<64; ++i) { // Second half of 4k block.
bmpBlockBits[i]=(bmpBlockBits[i]&mask)|bits;
}
} else {
// contains(FFFD)==FALSE
mask=~(0x10001<<0xd); // Lead byte 0xED.
for(i=32; i<64; ++i) { // Second half of 4k block.
bmpBlockBits[i]&=mask;
}
}
}
int32_t BMPSet::findCodePoint(UChar32 c, int32_t lo, int32_t hi) const {
/* Examples:
findCodePoint(c)
set list[] c=0 1 3 4 7 8
=== ============== ===========
[] [110000] 0 0 0 0 0 0
[\u0000-\u0003] [0, 4, 110000] 1 1 1 2 2 2
[\u0004-\u0007] [4, 8, 110000] 0 0 0 1 1 2
[:Any:] [0, 110000] 1 1 1 1 1 1
*/
// Return the smallest i such that c < list[i]. Assume
// list[len - 1] == HIGH and that c is legal (0..HIGH-1).
if (c < list[lo])
return lo;
// High runner test. c is often after the last range, so an
// initial check for this condition pays off.
if (lo >= hi || c >= list[hi-1])
return hi;
// invariant: c >= list[lo]
// invariant: c < list[hi]
for (;;) {
int32_t i = (lo + hi) >> 1;
if (i == lo) {
break; // Found!
} else if (c < list[i]) {
hi = i;
} else {
lo = i;
}
}
return hi;
}
UBool
BMPSet::contains(UChar32 c) const {
if((uint32_t)c<=0x7f) {
return (UBool)asciiBytes[c];
} else if((uint32_t)c<=0x7ff) {
return (UBool)((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0);
} else if((uint32_t)c<0xd800 || (c>=0xe000 && c<=0xffff)) {
int lead=c>>12;
uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
if(twoBits<=1) {
// All 64 code points with the same bits 15..6
// are either in the set or not.
return (UBool)twoBits;
} else {
// Look up the code point in its 4k block of code points.
return containsSlow(c, list4kStarts[lead], list4kStarts[lead+1]);
}
} else if((uint32_t)c<=0x10ffff) {
// surrogate or supplementary code point
return containsSlow(c, list4kStarts[0xd], list4kStarts[0x11]);
} else {
// Out-of-range code points get FALSE, consistent with long-standing
// behavior of UnicodeSet::contains(c).
return FALSE;
}
}
/*
* Check for sufficient length for trail unit for each surrogate pair.
* Handle single surrogates as surrogate code points as usual in ICU.
*/
const UChar *
BMPSet::span(const UChar *s, const UChar *limit, USetSpanCondition spanCondition) const {
UChar c, c2;
if(spanCondition) {
// span
do {
c=*s;
if(c<=0x7f) {
if(!asciiBytes[c]) {
break;
}
} else if(c<=0x7ff) {
if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))==0) {
break;
}
} else if(c<0xd800 || c>=0xe000) {
int lead=c>>12;
uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
if(twoBits<=1) {
// All 64 code points with the same bits 15..6
// are either in the set or not.
if(twoBits==0) {
break;
}
} else {
// Look up the code point in its 4k block of code points.
if(!containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
break;
}
}
} else if(c>=0xdc00 || (s+1)==limit || (c2=s[1])<0xdc00 || c2>=0xe000) {
// surrogate code point
if(!containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
break;
}
} else {
// surrogate pair
if(!containsSlow(U16_GET_SUPPLEMENTARY(c, c2), list4kStarts[0x10], list4kStarts[0x11])) {
break;
}
++s;
}
} while(++s<limit);
} else {
// span not
do {
c=*s;
if(c<=0x7f) {
if(asciiBytes[c]) {
break;
}
} else if(c<=0x7ff) {
if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0) {
break;
}
} else if(c<0xd800 || c>=0xe000) {
int lead=c>>12;
uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
if(twoBits<=1) {
// All 64 code points with the same bits 15..6
// are either in the set or not.
if(twoBits!=0) {
break;
}
} else {
// Look up the code point in its 4k block of code points.
if(containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
break;
}
}
} else if(c>=0xdc00 || (s+1)==limit || (c2=s[1])<0xdc00 || c2>=0xe000) {
// surrogate code point
if(containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
break;
}
} else {
// surrogate pair
if(containsSlow(U16_GET_SUPPLEMENTARY(c, c2), list4kStarts[0x10], list4kStarts[0x11])) {
break;
}
++s;
}
} while(++s<limit);
}
return s;
}
/* Symmetrical with span(). */
const UChar *
BMPSet::spanBack(const UChar *s, const UChar *limit, USetSpanCondition spanCondition) const {
UChar c, c2;
if(spanCondition) {
// span
for(;;) {
c=*(--limit);
if(c<=0x7f) {
if(!asciiBytes[c]) {
break;
}
} else if(c<=0x7ff) {
if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))==0) {
break;
}
} else if(c<0xd800 || c>=0xe000) {
int lead=c>>12;
uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
if(twoBits<=1) {
// All 64 code points with the same bits 15..6
// are either in the set or not.
if(twoBits==0) {
break;
}
} else {
// Look up the code point in its 4k block of code points.
if(!containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
break;
}
}
} else if(c<0xdc00 || s==limit || (c2=*(limit-1))<0xd800 || c2>=0xdc00) {
// surrogate code point
if(!containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
break;
}
} else {
// surrogate pair
if(!containsSlow(U16_GET_SUPPLEMENTARY(c2, c), list4kStarts[0x10], list4kStarts[0x11])) {
break;
}
--limit;
}
if(s==limit) {
return s;
}
}
} else {
// span not
for(;;) {
c=*(--limit);
if(c<=0x7f) {
if(asciiBytes[c]) {
break;
}
} else if(c<=0x7ff) {
if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0) {
break;
}
} else if(c<0xd800 || c>=0xe000) {
int lead=c>>12;
uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
if(twoBits<=1) {
// All 64 code points with the same bits 15..6
// are either in the set or not.
if(twoBits!=0) {
break;
}
} else {
// Look up the code point in its 4k block of code points.
if(containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
break;
}
}
} else if(c<0xdc00 || s==limit || (c2=*(limit-1))<0xd800 || c2>=0xdc00) {
// surrogate code point
if(containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
break;
}
} else {
// surrogate pair
if(containsSlow(U16_GET_SUPPLEMENTARY(c2, c), list4kStarts[0x10], list4kStarts[0x11])) {
break;
}
--limit;
}
if(s==limit) {
return s;
}
}
}
return limit+1;
}
/*
* Precheck for sufficient trail bytes at end of string only once per span.
* Check validity.
*/
const uint8_t *
BMPSet::spanUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const {
const uint8_t *limit=s+length;
uint8_t b=*s;
if((int8_t)b>=0) {
// Initial all-ASCII span.
if(spanCondition) {
do {
if(!asciiBytes[b] || ++s==limit) {
return s;
}
b=*s;
} while((int8_t)b>=0);
} else {
do {
if(asciiBytes[b] || ++s==limit) {
return s;
}
b=*s;
} while((int8_t)b>=0);
}
length=(int32_t)(limit-s);
}
if(spanCondition!=USET_SPAN_NOT_CONTAINED) {
spanCondition=USET_SPAN_CONTAINED; // Pin to 0/1 values.
}
const uint8_t *limit0=limit;
/*
* Make sure that the last 1/2/3/4-byte sequence before limit is complete
* or runs into a lead byte.
* In the span loop compare s with limit only once
* per multi-byte character.
*
* Give a trailing illegal sequence the same value as the result of contains(FFFD),
* including it if that is part of the span, otherwise set limit0 to before
* the truncated sequence.
*/
b=*(limit-1);
if((int8_t)b<0) {
// b>=0x80: lead or trail byte
if(b<0xc0) {
// single trail byte, check for preceding 3- or 4-byte lead byte
if(length>=2 && (b=*(limit-2))>=0xe0) {
limit-=2;
if(asciiBytes[0x80]!=spanCondition) {
limit0=limit;
}
} else if(b<0xc0 && b>=0x80 && length>=3 && (b=*(limit-3))>=0xf0) {
// 4-byte lead byte with only two trail bytes
limit-=3;
if(asciiBytes[0x80]!=spanCondition) {
limit0=limit;
}
}
} else {
// lead byte with no trail bytes
--limit;
if(asciiBytes[0x80]!=spanCondition) {
limit0=limit;
}
}
}
uint8_t t1, t2, t3;
while(s<limit) {
b=*s;
if(b<0xc0) {
// ASCII; or trail bytes with the result of contains(FFFD).
if(spanCondition) {
do {
if(!asciiBytes[b]) {
return s;
} else if(++s==limit) {
return limit0;
}
b=*s;
} while(b<0xc0);
} else {
do {
if(asciiBytes[b]) {
return s;
} else if(++s==limit) {
return limit0;
}
b=*s;
} while(b<0xc0);
}
}
++s; // Advance past the lead byte.
if(b>=0xe0) {
if(b<0xf0) {
if( /* handle U+0000..U+FFFF inline */
(t1=(uint8_t)(s[0]-0x80)) <= 0x3f &&
(t2=(uint8_t)(s[1]-0x80)) <= 0x3f
) {
b&=0xf;
uint32_t twoBits=(bmpBlockBits[t1]>>b)&0x10001;
if(twoBits<=1) {
// All 64 code points with this lead byte and middle trail byte
// are either in the set or not.
if(twoBits!=(uint32_t)spanCondition) {
return s-1;
}
} else {
// Look up the code point in its 4k block of code points.
UChar32 c=(b<<12)|(t1<<6)|t2;
if(containsSlow(c, list4kStarts[b], list4kStarts[b+1]) != spanCondition) {
return s-1;
}
}
s+=2;
continue;
}
} else if( /* handle U+10000..U+10FFFF inline */
(t1=(uint8_t)(s[0]-0x80)) <= 0x3f &&
(t2=(uint8_t)(s[1]-0x80)) <= 0x3f &&
(t3=(uint8_t)(s[2]-0x80)) <= 0x3f
) {
// Give an illegal sequence the same value as the result of contains(FFFD).
UChar32 c=((UChar32)(b-0xf0)<<18)|((UChar32)t1<<12)|(t2<<6)|t3;
if( ( (0x10000<=c && c<=0x10ffff) ?
containsSlow(c, list4kStarts[0x10], list4kStarts[0x11]) :
asciiBytes[0x80]
) != spanCondition
) {
return s-1;
}
s+=3;
continue;
}
} else /* 0xc0<=b<0xe0 */ {
if( /* handle U+0000..U+07FF inline */
(t1=(uint8_t)(*s-0x80)) <= 0x3f
) {
if((USetSpanCondition)((table7FF[t1]&((uint32_t)1<<(b&0x1f)))!=0) != spanCondition) {
return s-1;
}
++s;
continue;
}
}
// Give an illegal sequence the same value as the result of contains(FFFD).
// Handle each byte of an illegal sequence separately to simplify the code;
// no need to optimize error handling.
if(asciiBytes[0x80]!=spanCondition) {
return s-1;
}
}
return limit0;
}
/*
* While going backwards through UTF-8 optimize only for ASCII.
* Unlike UTF-16, UTF-8 is not forward-backward symmetrical, that is, it is not
* possible to tell from the last byte in a multi-byte sequence how many
* preceding bytes there should be. Therefore, going backwards through UTF-8
* is much harder than going forward.
*/
int32_t
BMPSet::spanBackUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const {
if(spanCondition!=USET_SPAN_NOT_CONTAINED) {
spanCondition=USET_SPAN_CONTAINED; // Pin to 0/1 values.
}
uint8_t b;
do {
b=s[--length];
if((int8_t)b>=0) {
// ASCII sub-span
if(spanCondition) {
do {
if(!asciiBytes[b]) {
return length+1;
} else if(length==0) {
return 0;
}
b=s[--length];
} while((int8_t)b>=0);
} else {
do {
if(asciiBytes[b]) {
return length+1;
} else if(length==0) {
return 0;
}
b=s[--length];
} while((int8_t)b>=0);
}
}
int32_t prev=length;
UChar32 c;
if(b<0xc0) {
// trail byte: collect a multi-byte character
c=utf8_prevCharSafeBody(s, 0, &length, b, -1);
if(c<0) {
c=0xfffd;
}
} else {
// lead byte in last-trail position
c=0xfffd;
}
// c is a valid code point, not ASCII, not a surrogate
if(c<=0x7ff) {
if((USetSpanCondition)((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0) != spanCondition) {
return prev+1;
}
} else if(c<=0xffff) {
int lead=c>>12;
uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
if(twoBits<=1) {
// All 64 code points with the same bits 15..6
// are either in the set or not.
if(twoBits!=(uint32_t)spanCondition) {
return prev+1;
}
} else {
// Look up the code point in its 4k block of code points.
if(containsSlow(c, list4kStarts[lead], list4kStarts[lead+1]) != spanCondition) {
return prev+1;
}
}
} else {
if(containsSlow(c, list4kStarts[0x10], list4kStarts[0x11]) != spanCondition) {
return prev+1;
}
}
} while(length>0);
return 0;
}
U_NAMESPACE_END