The Tor Browser: intl/icu/source/common/bmpset.cpp@b8a032363ba2 (annotated)

intl/icu/source/common/bmpset.cpp@b8a032363ba2 (annotated)

intl/icu/source/common/bmpset.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
 ******************************************************************************
 *
 *   Copyright (C) 2007-2012, 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"
 #include "uassert.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) {
     U_ASSERT(start<limit);
     U_ASSERT(limit<=0x800);
     int32_t lead=start>>6;  // Named for UTF-8 2-byte lead byte with upper 5 bits.
     int32_t trail=start&0x3f;  // Named for UTF-8 2-byte trail byte with lower 6 bits.
     // 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;
             }
         }
         // limit<=0x800. If limit==0x800 then limitLead=32 and limitTrail=0.
         // In that case, bits=1<<limitLead is undefined but the bits value
         // is not used because trail<limitTrail is already false.
         bits=(uint32_t)1<<((limitLead == 0x20) ? (limitLead - 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;
         // trail byte: collect a multi-byte character
         // (or  lead byte in last-trail position)
         c=utf8_prevCharSafeBody(s, 0, &length, b, -3);
         // 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

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intl/icu/source/common/bmpset.cpp@b8a032363ba2 (annotated)

intl/icu/source/common/bmpset.cpp