The Tor Browser: intl/icu/source/common/ucnv_ext.cpp@fc2d59ddac77 (annotated)

intl/icu/source/common/ucnv_ext.cpp@fc2d59ddac77 (annotated)

intl/icu/source/common/ucnv_ext.cpp

Wed, 31 Dec 2014 07:22:50 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 07:22:50 +0100
branch: TOR_BUG_3246
changeset 4: fc2d59ddac77
permissions: -rw-r--r--

Correct previous dual key logic pending first delivery installment.

 /*
 ******************************************************************************
 *
 *   Copyright (C) 2003-2013, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 *
 ******************************************************************************
 *   file name:  ucnv_ext.cpp
 *   encoding:   US-ASCII
 *   tab size:   8 (not used)
 *   indentation:4
 *
 *   created on: 2003jun13
 *   created by: Markus W. Scherer
 *
 *   Conversion extensions
 */
 #include "unicode/utypes.h"
 #if !UCONFIG_NO_CONVERSION && !UCONFIG_NO_LEGACY_CONVERSION
 #include "unicode/uset.h"
 #include "ucnv_bld.h"
 #include "ucnv_cnv.h"
 #include "ucnv_ext.h"
 #include "cmemory.h"
 #include "uassert.h"
 /* to Unicode --------------------------------------------------------------- */
 /*
  * @return lookup value for the byte, if found; else 0
  */
 static inline uint32_t
 ucnv_extFindToU(const uint32_t *toUSection, int32_t length, uint8_t byte) {
     uint32_t word0, word;
     int32_t i, start, limit;
     /* check the input byte against the lowest and highest section bytes */
     start=(int32_t)UCNV_EXT_TO_U_GET_BYTE(toUSection[0]);
     limit=(int32_t)UCNV_EXT_TO_U_GET_BYTE(toUSection[length-1]);
     if(byte<start || limit<byte) {
         return 0; /* the byte is out of range */
     }
     if(length==((limit-start)+1)) {
         /* direct access on a linear array */
         return UCNV_EXT_TO_U_GET_VALUE(toUSection[byte-start]); /* could be 0 */
     }
     /* word0 is suitable for <=toUSection[] comparison, word for <toUSection[] */
     word0=UCNV_EXT_TO_U_MAKE_WORD(byte, 0);
     /*
      * Shift byte once instead of each section word and add 0xffffff.
      * We will compare the shifted/added byte (bbffffff) against
      * section words which have byte values in the same bit position.
      * If and only if byte bb < section byte ss then bbffffff<ssvvvvvv
      * for all v=0..f
      * so we need not mask off the lower 24 bits of each section word.
      */
     word=word0|UCNV_EXT_TO_U_VALUE_MASK;
     /* binary search */
     start=0;
     limit=length;
     for(;;) {
         i=limit-start;
         if(i<=1) {
             break; /* done */
         }
         /* start<limit-1 */
         if(i<=4) {
             /* linear search for the last part */
             if(word0<=toUSection[start]) {
                 break;
             }
             if(++start<limit && word0<=toUSection[start]) {
                 break;
             }
             if(++start<limit && word0<=toUSection[start]) {
                 break;
             }
             /* always break at start==limit-1 */
             ++start;
             break;
         }
         i=(start+limit)/2;
         if(word<toUSection[i]) {
             limit=i;
         } else {
             start=i;
         }
     }
     /* did we really find it? */
     if(start<limit && byte==UCNV_EXT_TO_U_GET_BYTE(word=toUSection[start])) {
         return UCNV_EXT_TO_U_GET_VALUE(word); /* never 0 */
     } else {
         return 0; /* not found */
     }
 }
 /*
  * TRUE if not an SI/SO stateful converter,
  * or if the match length fits with the current converter state
  */
 #define UCNV_EXT_TO_U_VERIFY_SISO_MATCH(sisoState, match) \
     ((sisoState)<0 || ((sisoState)==0) == (match==1))
 /*
  * this works like ucnv_extMatchFromU() except
  * - the first character is in pre
  * - no trie is used
  * - the returned matchLength is not offset by 2
  */
 static int32_t
 ucnv_extMatchToU(const int32_t *cx, int8_t sisoState,
                  const char *pre, int32_t preLength,
                  const char *src, int32_t srcLength,
                  uint32_t *pMatchValue,
                  UBool /*useFallback*/, UBool flush) {
     const uint32_t *toUTable, *toUSection;
     uint32_t value, matchValue;
     int32_t i, j, idx, length, matchLength;
     uint8_t b;
     if(cx==NULL || cx[UCNV_EXT_TO_U_LENGTH]<=0) {
         return 0; /* no extension data, no match */
     }
     /* initialize */
     toUTable=UCNV_EXT_ARRAY(cx, UCNV_EXT_TO_U_INDEX, uint32_t);
     idx=0;
     matchValue=0;
     i=j=matchLength=0;
     if(sisoState==0) {
         /* SBCS state of an SI/SO stateful converter, look at only exactly 1 byte */
         if(preLength>1) {
             return 0; /* no match of a DBCS sequence in SBCS mode */
         } else if(preLength==1) {
             srcLength=0;
         } else /* preLength==0 */ {
             if(srcLength>1) {
                 srcLength=1;
             }
         }
         flush=TRUE;
     }
     /* we must not remember fallback matches when not using fallbacks */
     /* match input units until there is a full match or the input is consumed */
     for(;;) {
         /* go to the next section */
         toUSection=toUTable+idx;
         /* read first pair of the section */
         value=*toUSection++;
         length=UCNV_EXT_TO_U_GET_BYTE(value);
         value=UCNV_EXT_TO_U_GET_VALUE(value);
         if( value!=0 &&
             (UCNV_EXT_TO_U_IS_ROUNDTRIP(value) ||
              TO_U_USE_FALLBACK(useFallback)) &&
             UCNV_EXT_TO_U_VERIFY_SISO_MATCH(sisoState, i+j)
         ) {
             /* remember longest match so far */
             matchValue=value;
             matchLength=i+j;
         }
         /* match pre[] then src[] */
         if(i<preLength) {
             b=(uint8_t)pre[i++];
         } else if(j<srcLength) {
             b=(uint8_t)src[j++];
         } else {
             /* all input consumed, partial match */
             if(flush || (length=(i+j))>UCNV_EXT_MAX_BYTES) {
                 /*
                  * end of the entire input stream, stop with the longest match so far
                  * or: partial match must not be longer than UCNV_EXT_MAX_BYTES
                  * because it must fit into state buffers
                  */
                 break;
             } else {
                 /* continue with more input next time */
                 return -length;
             }
         }
         /* search for the current UChar */
         value=ucnv_extFindToU(toUSection, length, b);
         if(value==0) {
             /* no match here, stop with the longest match so far */
             break;
         } else {
             if(UCNV_EXT_TO_U_IS_PARTIAL(value)) {
                 /* partial match, continue */
                 idx=(int32_t)UCNV_EXT_TO_U_GET_PARTIAL_INDEX(value);
             } else {
                 if( (UCNV_EXT_TO_U_IS_ROUNDTRIP(value) ||
                      TO_U_USE_FALLBACK(useFallback)) &&
                     UCNV_EXT_TO_U_VERIFY_SISO_MATCH(sisoState, i+j)
                 ) {
                     /* full match, stop with result */
                     matchValue=value;
                     matchLength=i+j;
                 } else {
                     /* full match on fallback not taken, stop with the longest match so far */
                 }
                 break;
             }
         }
     }
     if(matchLength==0) {
         /* no match at all */
         return 0;
     }
     /* return result */
     *pMatchValue=UCNV_EXT_TO_U_MASK_ROUNDTRIP(matchValue);
     return matchLength;
 }
 static inline void
 ucnv_extWriteToU(UConverter *cnv, const int32_t *cx,
                  uint32_t value,
                  UChar **target, const UChar *targetLimit,
                  int32_t **offsets, int32_t srcIndex,
                  UErrorCode *pErrorCode) {
     /* output the result */
     if(UCNV_EXT_TO_U_IS_CODE_POINT(value)) {
         /* output a single code point */
         ucnv_toUWriteCodePoint(
             cnv, UCNV_EXT_TO_U_GET_CODE_POINT(value),
             target, targetLimit,
             offsets, srcIndex,
             pErrorCode);
     } else {
         /* output a string - with correct data we have resultLength>0 */
         ucnv_toUWriteUChars(
             cnv,
             UCNV_EXT_ARRAY(cx, UCNV_EXT_TO_U_UCHARS_INDEX, UChar)+
                 UCNV_EXT_TO_U_GET_INDEX(value),
             UCNV_EXT_TO_U_GET_LENGTH(value),
             target, targetLimit,
             offsets, srcIndex,
             pErrorCode);
     }
 }
 /*
  * get the SI/SO toU state (state 0 is for SBCS, 1 for DBCS),
  * or 1 for DBCS-only,
  * or -1 if the converter is not SI/SO stateful
  *
  * Note: For SI/SO stateful converters getting here,
  * cnv->mode==0 is equivalent to firstLength==1.
  */
 #define UCNV_SISO_STATE(cnv) \
     ((cnv)->sharedData->mbcs.outputType==MBCS_OUTPUT_2_SISO ? (int8_t)(cnv)->mode : \
      (cnv)->sharedData->mbcs.outputType==MBCS_OUTPUT_DBCS_ONLY ? 1 : -1)
 /*
  * target<targetLimit; set error code for overflow
  */
 U_CFUNC UBool
 ucnv_extInitialMatchToU(UConverter *cnv, const int32_t *cx,
                         int32_t firstLength,
                         const char **src, const char *srcLimit,
                         UChar **target, const UChar *targetLimit,
                         int32_t **offsets, int32_t srcIndex,
                         UBool flush,
                         UErrorCode *pErrorCode) {
     uint32_t value = 0;  /* initialize output-only param to 0 to silence gcc */
     int32_t match;
     /* try to match */
     match=ucnv_extMatchToU(cx, (int8_t)UCNV_SISO_STATE(cnv),
                            (const char *)cnv->toUBytes, firstLength,
                            *src, (int32_t)(srcLimit-*src),
                            &value,
                            cnv->useFallback, flush);
     if(match>0) {
         /* advance src pointer for the consumed input */
         *src+=match-firstLength;
         /* write result to target */
         ucnv_extWriteToU(cnv, cx,
                          value,
                          target, targetLimit,
                          offsets, srcIndex,
                          pErrorCode);
         return TRUE;
     } else if(match<0) {
         /* save state for partial match */
         const char *s;
         int32_t j;
         /* copy the first code point */
         s=(const char *)cnv->toUBytes;
         cnv->preToUFirstLength=(int8_t)firstLength;
         for(j=0; j<firstLength; ++j) {
             cnv->preToU[j]=*s++;
         }
         /* now copy the newly consumed input */
         s=*src;
         match=-match;
         for(; j<match; ++j) {
             cnv->preToU[j]=*s++;
         }
         *src=s; /* same as *src=srcLimit; because we reached the end of input */
         cnv->preToULength=(int8_t)match;
         return TRUE;
     } else /* match==0 no match */ {
         return FALSE;
     }
 }
 U_CFUNC UChar32
 ucnv_extSimpleMatchToU(const int32_t *cx,
                        const char *source, int32_t length,
                        UBool useFallback) {
     uint32_t value = 0;  /* initialize output-only param to 0 to silence gcc */
     int32_t match;
     if(length<=0) {
         return 0xffff;
     }
     /* try to match */
     match=ucnv_extMatchToU(cx, -1,
                            source, length,
                            NULL, 0,
                            &value,
                            useFallback, TRUE);
     if(match==length) {
         /* write result for simple, single-character conversion */
         if(UCNV_EXT_TO_U_IS_CODE_POINT(value)) {
             return UCNV_EXT_TO_U_GET_CODE_POINT(value);
         }
     }
     /*
      * return no match because
      * - match>0 && value points to string: simple conversion cannot handle multiple code points
      * - match>0 && match!=length: not all input consumed, forbidden for this function
      * - match==0: no match found in the first place
      * - match<0: partial match, not supported for simple conversion (and flush==TRUE)
      */
     return 0xfffe;
 }
 /*
  * continue partial match with new input
  * never called for simple, single-character conversion
  */
 U_CFUNC void
 ucnv_extContinueMatchToU(UConverter *cnv,
                          UConverterToUnicodeArgs *pArgs, int32_t srcIndex,
                          UErrorCode *pErrorCode) {
     uint32_t value = 0;  /* initialize output-only param to 0 to silence gcc */
     int32_t match, length;
     match=ucnv_extMatchToU(cnv->sharedData->mbcs.extIndexes, (int8_t)UCNV_SISO_STATE(cnv),
                            cnv->preToU, cnv->preToULength,
                            pArgs->source, (int32_t)(pArgs->sourceLimit-pArgs->source),
                            &value,
                            cnv->useFallback, pArgs->flush);
     if(match>0) {
         if(match>=cnv->preToULength) {
             /* advance src pointer for the consumed input */
             pArgs->source+=match-cnv->preToULength;
             cnv->preToULength=0;
         } else {
             /* the match did not use all of preToU[] - keep the rest for replay */
             length=cnv->preToULength-match;
             uprv_memmove(cnv->preToU, cnv->preToU+match, length);
             cnv->preToULength=(int8_t)-length;
         }
         /* write result */
         ucnv_extWriteToU(cnv, cnv->sharedData->mbcs.extIndexes,
                          value,
                          &pArgs->target, pArgs->targetLimit,
                          &pArgs->offsets, srcIndex,
                          pErrorCode);
     } else if(match<0) {
         /* save state for partial match */
         const char *s;
         int32_t j;
         /* just _append_ the newly consumed input to preToU[] */
         s=pArgs->source;
         match=-match;
         for(j=cnv->preToULength; j<match; ++j) {
             cnv->preToU[j]=*s++;
         }
         pArgs->source=s; /* same as *src=srcLimit; because we reached the end of input */
         cnv->preToULength=(int8_t)match;
     } else /* match==0 */ {
         /*
          * no match
          *
          * We need to split the previous input into two parts:
          *
          * 1. The first codepage character is unmappable - that's how we got into
          *    trying the extension data in the first place.
          *    We need to move it from the preToU buffer
          *    to the error buffer, set an error code,
          *    and prepare the rest of the previous input for 2.
          *
          * 2. The rest of the previous input must be converted once we
          *    come back from the callback for the first character.
          *    At that time, we have to try again from scratch to convert
          *    these input characters.
          *    The replay will be handled by the ucnv.c conversion code.
          */
         /* move the first codepage character to the error field */
         uprv_memcpy(cnv->toUBytes, cnv->preToU, cnv->preToUFirstLength);
         cnv->toULength=cnv->preToUFirstLength;
         /* move the rest up inside the buffer */
         length=cnv->preToULength-cnv->preToUFirstLength;
         if(length>0) {
             uprv_memmove(cnv->preToU, cnv->preToU+cnv->preToUFirstLength, length);
         }
         /* mark preToU for replay */
         cnv->preToULength=(int8_t)-length;
         /* set the error code for unassigned */
         *pErrorCode=U_INVALID_CHAR_FOUND;
     }
 }
 /* from Unicode ------------------------------------------------------------- */
 // Use roundtrips, "good one-way" mappings, and some normal fallbacks.
 static inline UBool
 extFromUUseMapping(UBool useFallback, uint32_t value, UChar32 firstCP) {
     return
         ((value&UCNV_EXT_FROM_U_STATUS_MASK)!=0 ||
             FROM_U_USE_FALLBACK(useFallback, firstCP)) &&
         (value&UCNV_EXT_FROM_U_RESERVED_MASK)==0;
 }
 /*
  * @return index of the UChar, if found; else <0
  */
 static inline int32_t
 ucnv_extFindFromU(const UChar *fromUSection, int32_t length, UChar u) {
     int32_t i, start, limit;
     /* binary search */
     start=0;
     limit=length;
     for(;;) {
         i=limit-start;
         if(i<=1) {
             break; /* done */
         }
         /* start<limit-1 */
         if(i<=4) {
             /* linear search for the last part */
             if(u<=fromUSection[start]) {
                 break;
             }
             if(++start<limit && u<=fromUSection[start]) {
                 break;
             }
             if(++start<limit && u<=fromUSection[start]) {
                 break;
             }
             /* always break at start==limit-1 */
             ++start;
             break;
         }
         i=(start+limit)/2;
         if(u<fromUSection[i]) {
             limit=i;
         } else {
             start=i;
         }
     }
     /* did we really find it? */
     if(start<limit && u==fromUSection[start]) {
         return start;
     } else {
         return -1; /* not found */
     }
 }
 /*
  * @param cx pointer to extension data; if NULL, returns 0
  * @param firstCP the first code point before all the other UChars
  * @param pre UChars that must match; !initialMatch: partial match with them
  * @param preLength length of pre, >=0
  * @param src UChars that can be used to complete a match
  * @param srcLength length of src, >=0
  * @param pMatchValue [out] output result value for the match from the data structure
  * @param useFallback "use fallback" flag, usually from cnv->useFallback
  * @param flush TRUE if the end of the input stream is reached
  * @return >1: matched, return value=total match length (number of input units matched)
  *          1: matched, no mapping but request for <subchar1>
  *             (only for the first code point)
  *          0: no match
  *         <0: partial match, return value=negative total match length
  *             (partial matches are never returned for flush==TRUE)
  *             (partial matches are never returned as being longer than UCNV_EXT_MAX_UCHARS)
  *         the matchLength is 2 if only firstCP matched, and >2 if firstCP and
  *         further code units matched
  */
 static int32_t
 ucnv_extMatchFromU(const int32_t *cx,
                    UChar32 firstCP,
                    const UChar *pre, int32_t preLength,
                    const UChar *src, int32_t srcLength,
                    uint32_t *pMatchValue,
                    UBool useFallback, UBool flush) {
     const uint16_t *stage12, *stage3;
     const uint32_t *stage3b;
     const UChar *fromUTableUChars, *fromUSectionUChars;
     const uint32_t *fromUTableValues, *fromUSectionValues;
     uint32_t value, matchValue;
     int32_t i, j, idx, length, matchLength;
     UChar c;
     if(cx==NULL) {
         return 0; /* no extension data, no match */
     }
     /* trie lookup of firstCP */
     idx=firstCP>>10; /* stage 1 index */
     if(idx>=cx[UCNV_EXT_FROM_U_STAGE_1_LENGTH]) {
         return 0; /* the first code point is outside the trie */
     }
     stage12=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_STAGE_12_INDEX, uint16_t);
     stage3=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_STAGE_3_INDEX, uint16_t);
     idx=UCNV_EXT_FROM_U(stage12, stage3, idx, firstCP);
     stage3b=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_STAGE_3B_INDEX, uint32_t);
     value=stage3b[idx];
     if(value==0) {
         return 0;
     }
     /*
      * Tests for (value&UCNV_EXT_FROM_U_RESERVED_MASK)==0:
      * Do not interpret values with reserved bits used, for forward compatibility,
      * and do not even remember intermediate results with reserved bits used.
      */
     if(UCNV_EXT_TO_U_IS_PARTIAL(value)) {
         /* partial match, enter the loop below */
         idx=(int32_t)UCNV_EXT_FROM_U_GET_PARTIAL_INDEX(value);
         /* initialize */
         fromUTableUChars=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_UCHARS_INDEX, UChar);
         fromUTableValues=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_VALUES_INDEX, uint32_t);
         matchValue=0;
         i=j=matchLength=0;
         /* we must not remember fallback matches when not using fallbacks */
         /* match input units until there is a full match or the input is consumed */
         for(;;) {
             /* go to the next section */
             fromUSectionUChars=fromUTableUChars+idx;
             fromUSectionValues=fromUTableValues+idx;
             /* read first pair of the section */
             length=*fromUSectionUChars++;
             value=*fromUSectionValues++;
             if(value!=0 && extFromUUseMapping(useFallback, value, firstCP)) {
                 /* remember longest match so far */
                 matchValue=value;
                 matchLength=2+i+j;
             }
             /* match pre[] then src[] */
             if(i<preLength) {
                 c=pre[i++];
             } else if(j<srcLength) {
                 c=src[j++];
             } else {
                 /* all input consumed, partial match */
                 if(flush || (length=(i+j))>UCNV_EXT_MAX_UCHARS) {
                     /*
                      * end of the entire input stream, stop with the longest match so far
                      * or: partial match must not be longer than UCNV_EXT_MAX_UCHARS
                      * because it must fit into state buffers
                      */
                     break;
                 } else {
                     /* continue with more input next time */
                     return -(2+length);
                 }
             }
             /* search for the current UChar */
             idx=ucnv_extFindFromU(fromUSectionUChars, length, c);
             if(idx<0) {
                 /* no match here, stop with the longest match so far */
                 break;
             } else {
                 value=fromUSectionValues[idx];
                 if(UCNV_EXT_FROM_U_IS_PARTIAL(value)) {
                     /* partial match, continue */
                     idx=(int32_t)UCNV_EXT_FROM_U_GET_PARTIAL_INDEX(value);
                 } else {
                     if(extFromUUseMapping(useFallback, value, firstCP)) {
                         /* full match, stop with result */
                         matchValue=value;
                         matchLength=2+i+j;
                     } else {
                         /* full match on fallback not taken, stop with the longest match so far */
                     }
                     break;
                 }
             }
         }
         if(matchLength==0) {
             /* no match at all */
             return 0;
         }
     } else /* result from firstCP trie lookup */ {
         if(extFromUUseMapping(useFallback, value, firstCP)) {
             /* full match, stop with result */
             matchValue=value;
             matchLength=2;
         } else {
             /* fallback not taken */
             return 0;
         }
     }
     /* return result */
     if(matchValue==UCNV_EXT_FROM_U_SUBCHAR1) {
         return 1; /* assert matchLength==2 */
     }
     *pMatchValue=matchValue;
     return matchLength;
 }
 /*
  * @param value fromUnicode mapping table value; ignores roundtrip and reserved bits
  */
 static inline void
 ucnv_extWriteFromU(UConverter *cnv, const int32_t *cx,
                    uint32_t value,
                    char **target, const char *targetLimit,
                    int32_t **offsets, int32_t srcIndex,
                    UErrorCode *pErrorCode) {
     uint8_t buffer[1+UCNV_EXT_MAX_BYTES];
     const uint8_t *result;
     int32_t length, prevLength;
     length=UCNV_EXT_FROM_U_GET_LENGTH(value);
     value=(uint32_t)UCNV_EXT_FROM_U_GET_DATA(value);
     /* output the result */
     if(length<=UCNV_EXT_FROM_U_MAX_DIRECT_LENGTH) {
         /*
          * Generate a byte array and then write it below.
          * This is not the fastest possible way, but it should be ok for
          * extension mappings, and it is much simpler.
          * Offset and overflow handling are only done once this way.
          */
         uint8_t *p=buffer+1; /* reserve buffer[0] for shiftByte below */
         switch(length) {
         case 3:
             *p++=(uint8_t)(value>>16);
         case 2: /*fall through*/
             *p++=(uint8_t)(value>>8);
         case 1: /*fall through*/
             *p++=(uint8_t)value;
         default:
             break; /* will never occur */
         }
         result=buffer+1;
     } else {
         result=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_BYTES_INDEX, uint8_t)+value;
     }
     /* with correct data we have length>0 */
     if((prevLength=cnv->fromUnicodeStatus)!=0) {
         /* handle SI/SO stateful output */
         uint8_t shiftByte;
         if(prevLength>1 && length==1) {
             /* change from double-byte mode to single-byte */
             shiftByte=(uint8_t)UCNV_SI;
             cnv->fromUnicodeStatus=1;
         } else if(prevLength==1 && length>1) {
             /* change from single-byte mode to double-byte */
             shiftByte=(uint8_t)UCNV_SO;
             cnv->fromUnicodeStatus=2;
         } else {
             shiftByte=0;
         }
         if(shiftByte!=0) {
             /* prepend the shift byte to the result bytes */
             buffer[0]=shiftByte;
             if(result!=buffer+1) {
                 uprv_memcpy(buffer+1, result, length);
             }
             result=buffer;
             ++length;
         }
     }
     ucnv_fromUWriteBytes(cnv, (const char *)result, length,
                          target, targetLimit,
                          offsets, srcIndex,
                          pErrorCode);
 }
 /*
  * target<targetLimit; set error code for overflow
  */
 U_CFUNC UBool
 ucnv_extInitialMatchFromU(UConverter *cnv, const int32_t *cx,
                           UChar32 cp,
                           const UChar **src, const UChar *srcLimit,
                           char **target, const char *targetLimit,
                           int32_t **offsets, int32_t srcIndex,
                           UBool flush,
                           UErrorCode *pErrorCode) {
     uint32_t value = 0;  /* initialize output-only param to 0 to silence gcc */
     int32_t match;
     /* try to match */
     match=ucnv_extMatchFromU(cx, cp,
                              NULL, 0,
                              *src, (int32_t)(srcLimit-*src),
                              &value,
                              cnv->useFallback, flush);
     /* reject a match if the result is a single byte for DBCS-only */
     if( match>=2 &&
         !(UCNV_EXT_FROM_U_GET_LENGTH(value)==1 &&
           cnv->sharedData->mbcs.outputType==MBCS_OUTPUT_DBCS_ONLY)
     ) {
         /* advance src pointer for the consumed input */
         *src+=match-2; /* remove 2 for the initial code point */
         /* write result to target */
         ucnv_extWriteFromU(cnv, cx,
                            value,
                            target, targetLimit,
                            offsets, srcIndex,
                            pErrorCode);
         return TRUE;
     } else if(match<0) {
         /* save state for partial match */
         const UChar *s;
         int32_t j;
         /* copy the first code point */
         cnv->preFromUFirstCP=cp;
         /* now copy the newly consumed input */
         s=*src;
         match=-match-2; /* remove 2 for the initial code point */
         for(j=0; j<match; ++j) {
             cnv->preFromU[j]=*s++;
         }
         *src=s; /* same as *src=srcLimit; because we reached the end of input */
         cnv->preFromULength=(int8_t)match;
         return TRUE;
     } else if(match==1) {
         /* matched, no mapping but request for <subchar1> */
         cnv->useSubChar1=TRUE;
         return FALSE;
     } else /* match==0 no match */ {
         return FALSE;
     }
 }
 /*
  * Used by ISO 2022 implementation.
  * @return number of bytes in *pValue; negative number if fallback; 0 for no mapping
  */
 U_CFUNC int32_t
 ucnv_extSimpleMatchFromU(const int32_t *cx,
                          UChar32 cp, uint32_t *pValue,
                          UBool useFallback) {
     uint32_t value;
     int32_t match;
     /* try to match */
     match=ucnv_extMatchFromU(cx,
                              cp,
                              NULL, 0,
                              NULL, 0,
                              &value,
                              useFallback, TRUE);
     if(match>=2) {
         /* write result for simple, single-character conversion */
         int32_t length;
         int isRoundtrip;
         isRoundtrip=UCNV_EXT_FROM_U_IS_ROUNDTRIP(value);
         length=UCNV_EXT_FROM_U_GET_LENGTH(value);
         value=(uint32_t)UCNV_EXT_FROM_U_GET_DATA(value);
         if(length<=UCNV_EXT_FROM_U_MAX_DIRECT_LENGTH) {
             *pValue=value;
             return isRoundtrip ? length : -length;
 #if 0 /* not currently used */
         } else if(length==4) {
             /* de-serialize a 4-byte result */
             const uint8_t *result=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_BYTES_INDEX, uint8_t)+value;
             *pValue=
                 ((uint32_t)result[0]<<24)|
                 ((uint32_t)result[1]<<16)|
                 ((uint32_t)result[2]<<8)|
                 result[3];
             return isRoundtrip ? 4 : -4;
 #endif
         }
     }
     /*
      * return no match because
      * - match>1 && resultLength>4: result too long for simple conversion
      * - match==1: no match found, <subchar1> preferred
      * - match==0: no match found in the first place
      * - match<0: partial match, not supported for simple conversion (and flush==TRUE)
      */
     return 0;
 }
 /*
  * continue partial match with new input, requires cnv->preFromUFirstCP>=0
  * never called for simple, single-character conversion
  */
 U_CFUNC void
 ucnv_extContinueMatchFromU(UConverter *cnv,
                            UConverterFromUnicodeArgs *pArgs, int32_t srcIndex,
                            UErrorCode *pErrorCode) {
     uint32_t value = 0;  /* initialize output-only param to 0 to silence gcc */
     int32_t match;
     match=ucnv_extMatchFromU(cnv->sharedData->mbcs.extIndexes,
                              cnv->preFromUFirstCP,
                              cnv->preFromU, cnv->preFromULength,
                              pArgs->source, (int32_t)(pArgs->sourceLimit-pArgs->source),
                              &value,
                              cnv->useFallback, pArgs->flush);
     if(match>=2) {
         match-=2; /* remove 2 for the initial code point */
         if(match>=cnv->preFromULength) {
             /* advance src pointer for the consumed input */
             pArgs->source+=match-cnv->preFromULength;
             cnv->preFromULength=0;
         } else {
             /* the match did not use all of preFromU[] - keep the rest for replay */
             int32_t length=cnv->preFromULength-match;
             uprv_memmove(cnv->preFromU, cnv->preFromU+match, length*U_SIZEOF_UCHAR);
             cnv->preFromULength=(int8_t)-length;
         }
         /* finish the partial match */
         cnv->preFromUFirstCP=U_SENTINEL;
         /* write result */
         ucnv_extWriteFromU(cnv, cnv->sharedData->mbcs.extIndexes,
                            value,
                            &pArgs->target, pArgs->targetLimit,
                            &pArgs->offsets, srcIndex,
                            pErrorCode);
     } else if(match<0) {
         /* save state for partial match */
         const UChar *s;
         int32_t j;
         /* just _append_ the newly consumed input to preFromU[] */
         s=pArgs->source;
         match=-match-2; /* remove 2 for the initial code point */
         for(j=cnv->preFromULength; j<match; ++j) {
             U_ASSERT(j>=0);
             cnv->preFromU[j]=*s++;
         }
         pArgs->source=s; /* same as *src=srcLimit; because we reached the end of input */
         cnv->preFromULength=(int8_t)match;
     } else /* match==0 or 1 */ {
         /*
          * no match
          *
          * We need to split the previous input into two parts:
          *
          * 1. The first code point is unmappable - that's how we got into
          *    trying the extension data in the first place.
          *    We need to move it from the preFromU buffer
          *    to the error buffer, set an error code,
          *    and prepare the rest of the previous input for 2.
          *
          * 2. The rest of the previous input must be converted once we
          *    come back from the callback for the first code point.
          *    At that time, we have to try again from scratch to convert
          *    these input characters.
          *    The replay will be handled by the ucnv.c conversion code.
          */
         if(match==1) {
             /* matched, no mapping but request for <subchar1> */
             cnv->useSubChar1=TRUE;
         }
         /* move the first code point to the error field */
         cnv->fromUChar32=cnv->preFromUFirstCP;
         cnv->preFromUFirstCP=U_SENTINEL;
         /* mark preFromU for replay */
         cnv->preFromULength=-cnv->preFromULength;
         /* set the error code for unassigned */
         *pErrorCode=U_INVALID_CHAR_FOUND;
     }
 }
 static UBool
 extSetUseMapping(UConverterUnicodeSet which, int32_t minLength, uint32_t value) {
     if(which==UCNV_ROUNDTRIP_SET) {
         // Add only code points for which the roundtrip flag is set.
         // Do not add any fallbacks, even if ucnv_fromUnicode() would use them
         // (fallbacks from PUA). See the API docs for ucnv_getUnicodeSet().
         //
         // By analogy, also do not add "good one-way" mappings.
         //
         // Do not add entries with reserved bits set.
         if(((value&(UCNV_EXT_FROM_U_ROUNDTRIP_FLAG|UCNV_EXT_FROM_U_RESERVED_MASK))!=
                 UCNV_EXT_FROM_U_ROUNDTRIP_FLAG)) {
             return FALSE;
         }
     } else /* UCNV_ROUNDTRIP_AND_FALLBACK_SET */ {
         // Do not add entries with reserved bits set.
         if((value&UCNV_EXT_FROM_U_RESERVED_MASK)!=0) {
             return FALSE;
         }
     }
     // Do not add <subchar1> entries or other (future?) pseudo-entries
     // with an output length of 0.
     return UCNV_EXT_FROM_U_GET_LENGTH(value)>=minLength;
 }
 static void
 ucnv_extGetUnicodeSetString(const UConverterSharedData *sharedData,
                             const int32_t *cx,
                             const USetAdder *sa,
                             UConverterUnicodeSet which,
                             int32_t minLength,
                             UChar32 firstCP,
                             UChar s[UCNV_EXT_MAX_UCHARS], int32_t length,
                             int32_t sectionIndex,
                             UErrorCode *pErrorCode) {
     const UChar *fromUSectionUChars;
     const uint32_t *fromUSectionValues;
     uint32_t value;
     int32_t i, count;
     fromUSectionUChars=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_UCHARS_INDEX, UChar)+sectionIndex;
     fromUSectionValues=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_VALUES_INDEX, uint32_t)+sectionIndex;
     /* read first pair of the section */
     count=*fromUSectionUChars++;
     value=*fromUSectionValues++;
     if(extSetUseMapping(which, minLength, value)) {
         if(length==U16_LENGTH(firstCP)) {
             /* add the initial code point */
             sa->add(sa->set, firstCP);
         } else {
             /* add the string so far */
             sa->addString(sa->set, s, length);
         }
     }
     for(i=0; i<count; ++i) {
         /* append this code unit and recurse or add the string */
         s[length]=fromUSectionUChars[i];
         value=fromUSectionValues[i];
         if(value==0) {
             /* no mapping, do nothing */
         } else if(UCNV_EXT_FROM_U_IS_PARTIAL(value)) {
             ucnv_extGetUnicodeSetString(
                 sharedData, cx, sa, which, minLength,
                 firstCP, s, length+1,
                 (int32_t)UCNV_EXT_FROM_U_GET_PARTIAL_INDEX(value),
                 pErrorCode);
         } else if(extSetUseMapping(which, minLength, value)) {
             sa->addString(sa->set, s, length+1);
         }
     }
 }
 U_CFUNC void
 ucnv_extGetUnicodeSet(const UConverterSharedData *sharedData,
                       const USetAdder *sa,
                       UConverterUnicodeSet which,
                       UConverterSetFilter filter,
                       UErrorCode *pErrorCode) {
     const int32_t *cx;
     const uint16_t *stage12, *stage3, *ps2, *ps3;
     const uint32_t *stage3b;
     uint32_t value;
     int32_t st1, stage1Length, st2, st3, minLength;
     UChar s[UCNV_EXT_MAX_UCHARS];
     UChar32 c;
     int32_t length;
     cx=sharedData->mbcs.extIndexes;
     if(cx==NULL) {
         return;
     }
     stage12=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_STAGE_12_INDEX, uint16_t);
     stage3=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_STAGE_3_INDEX, uint16_t);
     stage3b=UCNV_EXT_ARRAY(cx, UCNV_EXT_FROM_U_STAGE_3B_INDEX, uint32_t);
     stage1Length=cx[UCNV_EXT_FROM_U_STAGE_1_LENGTH];
     /* enumerate the from-Unicode trie table */
     c=0; /* keep track of the current code point while enumerating */
     if(filter==UCNV_SET_FILTER_2022_CN) {
         minLength=3;
     } else if( sharedData->mbcs.outputType==MBCS_OUTPUT_DBCS_ONLY ||
                filter!=UCNV_SET_FILTER_NONE
     ) {
         /* DBCS-only, ignore single-byte results */
         minLength=2;
     } else {
         minLength=1;
     }
     /*
      * the trie enumeration is almost the same as
      * in MBCSGetUnicodeSet() for MBCS_OUTPUT_1
      */
     for(st1=0; st1<stage1Length; ++st1) {
         st2=stage12[st1];
         if(st2>stage1Length) {
             ps2=stage12+st2;
             for(st2=0; st2<64; ++st2) {
                 if((st3=(int32_t)ps2[st2]<<UCNV_EXT_STAGE_2_LEFT_SHIFT)!=0) {
                     /* read the stage 3 block */
                     ps3=stage3+st3;
                     do {
                         value=stage3b[*ps3++];
                         if(value==0) {
                             /* no mapping, do nothing */
                         } else if(UCNV_EXT_FROM_U_IS_PARTIAL(value)) {
                             // Recurse for partial results.
                             length=0;
                             U16_APPEND_UNSAFE(s, length, c);
                             ucnv_extGetUnicodeSetString(
                                 sharedData, cx, sa, which, minLength,
                                 c, s, length,
                                 (int32_t)UCNV_EXT_FROM_U_GET_PARTIAL_INDEX(value),
                                 pErrorCode);
                         } else if(extSetUseMapping(which, minLength, value)) {
                             switch(filter) {
                             case UCNV_SET_FILTER_2022_CN:
                                 if(!(UCNV_EXT_FROM_U_GET_LENGTH(value)==3 && UCNV_EXT_FROM_U_GET_DATA(value)<=0x82ffff)) {
                                     continue;
                                 }
                                 break;
                             case UCNV_SET_FILTER_SJIS:
                                 if(!(UCNV_EXT_FROM_U_GET_LENGTH(value)==2 && (value=UCNV_EXT_FROM_U_GET_DATA(value))>=0x8140 && value<=0xeffc)) {
                                     continue;
                                 }
                                 break;
                             case UCNV_SET_FILTER_GR94DBCS:
                                 if(!(UCNV_EXT_FROM_U_GET_LENGTH(value)==2 &&
                                      (uint16_t)((value=UCNV_EXT_FROM_U_GET_DATA(value))-0xa1a1)<=(0xfefe - 0xa1a1) &&
                                      (uint8_t)(value-0xa1)<=(0xfe - 0xa1))) {
                                     continue;
                                 }
                                 break;
                             case UCNV_SET_FILTER_HZ:
                                 if(!(UCNV_EXT_FROM_U_GET_LENGTH(value)==2 &&
                                      (uint16_t)((value=UCNV_EXT_FROM_U_GET_DATA(value))-0xa1a1)<=(0xfdfe - 0xa1a1) &&
                                      (uint8_t)(value-0xa1)<=(0xfe - 0xa1))) {
                                     continue;
                                 }
                                 break;
                             default:
                                 /*
                                  * UCNV_SET_FILTER_NONE,
                                  * or UCNV_SET_FILTER_DBCS_ONLY which is handled via minLength
                                  */
                                 break;
                             }
                             sa->add(sa->set, c);
                         }
                     } while((++c&0xf)!=0);
                 } else {
                     c+=16; /* empty stage 3 block */
                 }
             }
         } else {
             c+=1024; /* empty stage 2 block */
         }
     }
 }
 #endif /* #if !UCONFIG_NO_LEGACY_CONVERSION */

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intl/icu/source/common/ucnv_ext.cpp@fc2d59ddac77 (annotated)

intl/icu/source/common/ucnv_ext.cpp