X-Git-Url: https://git.saurik.com/apple/icu.git/blobdiff_plain/73c04bcfe1096173b00431f0cdc742894b15eef0..ef6cf650f4a75c3f97de06b51fa104f2069b9ea2:/icuSources/common/utf_impl.c diff --git a/icuSources/common/utf_impl.c b/icuSources/common/utf_impl.c index 8f45546b..ce65e14d 100644 --- a/icuSources/common/utf_impl.c +++ b/icuSources/common/utf_impl.c @@ -1,7 +1,7 @@ /* ****************************************************************************** * -* Copyright (C) 1999-2006, International Business Machines +* Copyright (C) 1999-2012, International Business Machines * Corporation and others. All Rights Reserved. * ****************************************************************************** @@ -23,6 +23,10 @@ #endif #include "unicode/utypes.h" +#include "unicode/utf.h" +#include "unicode/utf8.h" +#include "unicode/utf_old.h" +#include "uassert.h" /* * This table could be replaced on many machines by @@ -82,13 +86,31 @@ utf8_errorValue[6]={ 0x3ffffff, 0x7fffffff }; +static UChar32 +errorValue(int32_t count, int8_t strict) { + if(strict>=0) { + return utf8_errorValue[count]; + } else if(strict==-3) { + return 0xfffd; + } else { + return U_SENTINEL; + } +} + /* - * Handle the non-inline part of the U8_NEXT() macro and its obsolete sibling - * UTF8_NEXT_CHAR_SAFE(). + * Handle the non-inline part of the U8_NEXT() and U8_NEXT_FFFD() macros + * and their obsolete sibling UTF8_NEXT_CHAR_SAFE(). + * + * U8_NEXT() supports NUL-terminated strings indicated via length<0. * * The "strict" parameter controls the error behavior: - * <0 "Safe" behavior of U8_NEXT(): All illegal byte sequences yield a negative - * code point result. + * <0 "Safe" behavior of U8_NEXT(): + * -1: All illegal byte sequences yield U_SENTINEL=-1. + * -2: Same as -1, except for lenient treatment of surrogate code points as legal. + * Some implementations use this for roundtripping of + * Unicode 16-bit strings that are not well-formed UTF-16, that is, they + * contain unpaired surrogates. + * -3: All illegal byte sequences yield U+FFFD. * 0 Obsolete "safe" behavior of UTF8_NEXT_CHAR_SAFE(..., FALSE): * All illegal byte sequences yield a positive code point such that this * result code point would be encoded with the same number of bytes as @@ -97,101 +119,64 @@ utf8_errorValue[6]={ * Same as the obsolete "safe" behavior, but non-characters are also treated * like illegal sequences. * - * The special negative (<0) value -2 is used for lenient treatment of surrogate - * code points as legal. Some implementations use this for roundtripping of - * Unicode 16-bit strings that are not well-formed UTF-16, that is, they - * contain unpaired surrogates. - * * Note that a UBool is the same as an int8_t. */ U_CAPI UChar32 U_EXPORT2 utf8_nextCharSafeBody(const uint8_t *s, int32_t *pi, int32_t length, UChar32 c, UBool strict) { int32_t i=*pi; - uint8_t count=UTF8_COUNT_TRAIL_BYTES(c); - if((i)+count<=(length)) { - uint8_t trail, illegal=0; + uint8_t count=U8_COUNT_TRAIL_BYTES(c); + U_ASSERT(count <= 5); /* U8_COUNT_TRAIL_BYTES returns value 0...5 */ + if(i+count<=length || length<0) { + uint8_t trail; - UTF8_MASK_LEAD_BYTE((c), count); - /* count==0 for illegally leading trail bytes and the illegal bytes 0xfe and 0xff */ + U8_MASK_LEAD_BYTE(c, count); + /* support NUL-terminated strings: do not read beyond the first non-trail byte */ switch(count) { /* each branch falls through to the next one */ + case 0: + /* count==0 for illegally leading trail bytes and the illegal bytes 0xfe and 0xff */ case 5: case 4: /* count>=4 is always illegal: no more than 3 trail bytes in Unicode's UTF-8 */ - illegal=1; break; case 3: - trail=s[(i)++]; - (c)=((c)<<6)|(trail&0x3f); - if(c<0x110) { - illegal|=(trail&0xc0)^0x80; - } else { - /* code point>0x10ffff, outside Unicode */ - illegal=1; - break; - } + trail=s[i++]-0x80; + c=(c<<6)|trail; + /* c>=0x110 would result in code point>0x10ffff, outside Unicode */ + if(c>=0x110 || trail>0x3f) { break; } case 2: - trail=s[(i)++]; - (c)=((c)<<6)|(trail&0x3f); - illegal|=(trail&0xc0)^0x80; + trail=s[i++]-0x80; + c=(c<<6)|trail; + /* + * test for a surrogate d800..dfff unless we are lenient: + * before the last (c<<6), a surrogate is c=360..37f + */ + if(((c&0xffe0)==0x360 && strict!=-2) || trail>0x3f) { break; } case 1: - trail=s[(i)++]; - (c)=((c)<<6)|(trail&0x3f); - illegal|=(trail&0xc0)^0x80; - break; - case 0: - if(strict>=0) { - return UTF8_ERROR_VALUE_1; - } else { - return U_SENTINEL; + trail=s[i++]-0x80; + c=(c<<6)|trail; + if(trail>0x3f) { break; } + /* correct sequence - all trail bytes have (b7..b6)==(10) */ + if(c>=utf8_minLegal[count] && + /* strict: forbid non-characters like U+fffe */ + (strict<=0 || !U_IS_UNICODE_NONCHAR(c))) { + *pi=i; + return c; } /* no default branch to optimize switch() - all values are covered */ } + } else { + /* too few bytes left */ + count=length-i; + } - /* - * All the error handling should return a value - * that needs count bytes so that UTF8_GET_CHAR_SAFE() works right. - * - * Starting with Unicode 3.0.1, non-shortest forms are illegal. - * Starting with Unicode 3.2, surrogate code points must not be - * encoded in UTF-8, and there are no irregular sequences any more. - * - * U8_ macros (new in ICU 2.4) return negative values for error conditions. - */ - - /* correct sequence - all trail bytes have (b7..b6)==(10)? */ - /* illegal is also set if count>=4 */ - if(illegal || (c)0 && UTF8_IS_TRAIL(s[i])) { - ++(i); - --count; - } - if(strict>=0) { - c=utf8_errorValue[errorCount-count]; - } else { - c=U_SENTINEL; - } - } else if((strict)>0 && UTF_IS_UNICODE_NONCHAR(c)) { - /* strict: forbid non-characters like U+fffe */ - c=utf8_errorValue[count]; - } - } else /* too few bytes left */ { - /* error handling */ - int32_t i0=i; - /* don't just set (i)=(length) in case there is an illegal sequence */ - while((i)<(length) && UTF8_IS_TRAIL(s[i])) { - ++(i); - } - if(strict>=0) { - c=utf8_errorValue[i-i0]; - } else { - c=U_SENTINEL; - } + /* error handling */ + i=*pi; + while(count>0 && U8_IS_TRAIL(s[i])) { + ++i; + --count; } + c=errorValue(i-*pi, strict); *pi=i; return c; } @@ -246,18 +231,15 @@ utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, U int32_t i=*pi; uint8_t b, count=1, shift=6; + if(!U8_IS_TRAIL(c)) { return errorValue(0, strict); } + /* extract value bits from the last trail byte */ c&=0x3f; for(;;) { if(i<=start) { /* no lead byte at all */ - if(strict>=0) { - return UTF8_ERROR_VALUE_1; - } else { - return U_SENTINEL; - } - /*break;*/ + return errorValue(0, strict); } /* read another previous byte */ @@ -265,23 +247,19 @@ utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, U if((uint8_t)(b-0x80)<0x7e) { /* 0x80<=b<0xfe */ if(b&0x40) { /* lead byte, this will always end the loop */ - uint8_t shouldCount=UTF8_COUNT_TRAIL_BYTES(b); + uint8_t shouldCount=U8_COUNT_TRAIL_BYTES(b); if(count==shouldCount) { /* set the new position */ *pi=i; - UTF8_MASK_LEAD_BYTE(b, count); + U8_MASK_LEAD_BYTE(b, count); c|=(UChar32)b<=4 || c>0x10ffff || c0 && UTF_IS_UNICODE_NONCHAR(c))) { + if(count>=4 || c>0x10ffff || c0 && U_IS_UNICODE_NONCHAR(c))) { /* illegal sequence or (strict and non-character) */ if(count>=4) { count=3; } - if(strict>=0) { - c=utf8_errorValue[count]; - } else { - c=U_SENTINEL; - } + c=errorValue(count, strict); } else { /* exit with correct c */ } @@ -291,17 +269,9 @@ utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, U include the trail byte that we started with */ if(count=0) { - c=utf8_errorValue[count]; - } else { - c=U_SENTINEL; - } + c=errorValue(count, strict); } else { - if(strict>=0) { - c=UTF8_ERROR_VALUE_1; - } else { - c=U_SENTINEL; - } + c=errorValue(0, strict); } } break; @@ -312,20 +282,12 @@ utf8_prevCharSafeBody(const uint8_t *s, int32_t start, int32_t *pi, UChar32 c, U shift+=6; } else { /* more than 5 trail bytes is illegal */ - if(strict>=0) { - c=UTF8_ERROR_VALUE_1; - } else { - c=U_SENTINEL; - } + c=errorValue(0, strict); break; } } else { /* single-byte character precedes trailing bytes */ - if(strict>=0) { - c=UTF8_ERROR_VALUE_1; - } else { - c=U_SENTINEL; - } + c=errorValue(0, strict); break; } } @@ -351,7 +313,7 @@ utf8_back1SafeBody(const uint8_t *s, int32_t start, int32_t i) { if((uint8_t)(b-0x80)>=0x7e) { /* not 0x80<=b<0xfe */ break; } else if(b>=0xc0) { - if(UTF8_COUNT_TRAIL_BYTES(b)>=(i-I)) { + if(U8_COUNT_TRAIL_BYTES(b)>=(i-I)) { return I; } else { break;