The Tor Browser: intl/icu/source/common/unicode/unorm.h@6474c204b198 (annotated)

intl/icu/source/common/unicode/unorm.h@6474c204b198 (annotated)

intl/icu/source/common/unicode/unorm.h

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
 *******************************************************************************
 * Copyright (c) 1996-2010, International Business Machines Corporation
 *               and others. All Rights Reserved.
 *******************************************************************************
 * File unorm.h
 *
 * Created by: Vladimir Weinstein 12052000
 *
 * Modification history :
 *
 * Date        Name        Description
 * 02/01/01    synwee      Added normalization quickcheck enum and method.
 */
 #ifndef UNORM_H
 #define UNORM_H
 #include "unicode/utypes.h"
 #if !UCONFIG_NO_NORMALIZATION
 #include "unicode/uiter.h"
 #include "unicode/unorm2.h"
 /**
  * \file
  * \brief C API: Unicode Normalization
  *
  * <h2>Unicode normalization API</h2>
  *
  * Note: This API has been replaced by the unorm2.h API and is only available
  * for backward compatibility. The functions here simply delegate to the
  * unorm2.h functions, for example unorm2_getInstance() and unorm2_normalize().
  * There is one exception: The new API does not provide a replacement for unorm_compare().
  *
  * <code>unorm_normalize</code> transforms Unicode text into an equivalent composed or
  * decomposed form, allowing for easier sorting and searching of text.
  * <code>unorm_normalize</code> supports the standard normalization forms described in
  * <a href="http://www.unicode.org/unicode/reports/tr15/" target="unicode">
  * Unicode Standard Annex #15: Unicode Normalization Forms</a>.
  *
  * Characters with accents or other adornments can be encoded in
  * several different ways in Unicode.  For example, take the character A-acute.
  * In Unicode, this can be encoded as a single character (the
  * "composed" form):
  *
  * \code
  *      00C1    LATIN CAPITAL LETTER A WITH ACUTE
  * \endcode
  *
  * or as two separate characters (the "decomposed" form):
  *
  * \code
  *      0041    LATIN CAPITAL LETTER A
  *      0301    COMBINING ACUTE ACCENT
  * \endcode
  *
  * To a user of your program, however, both of these sequences should be
  * treated as the same "user-level" character "A with acute accent".  When you are searching or
  * comparing text, you must ensure that these two sequences are treated
  * equivalently.  In addition, you must handle characters with more than one
  * accent.  Sometimes the order of a character's combining accents is
  * significant, while in other cases accent sequences in different orders are
  * really equivalent.
  *
  * Similarly, the string "ffi" can be encoded as three separate letters:
  *
  * \code
  *      0066    LATIN SMALL LETTER F
  *      0066    LATIN SMALL LETTER F
  *      0069    LATIN SMALL LETTER I
  * \endcode
  *
  * or as the single character
  *
  * \code
  *      FB03    LATIN SMALL LIGATURE FFI
  * \endcode
  *
  * The ffi ligature is not a distinct semantic character, and strictly speaking
  * it shouldn't be in Unicode at all, but it was included for compatibility
  * with existing character sets that already provided it.  The Unicode standard
  * identifies such characters by giving them "compatibility" decompositions
  * into the corresponding semantic characters.  When sorting and searching, you
  * will often want to use these mappings.
  *
  * <code>unorm_normalize</code> helps solve these problems by transforming text into the
  * canonical composed and decomposed forms as shown in the first example above.
  * In addition, you can have it perform compatibility decompositions so that
  * you can treat compatibility characters the same as their equivalents.
  * Finally, <code>unorm_normalize</code> rearranges accents into the proper canonical
  * order, so that you do not have to worry about accent rearrangement on your
  * own.
  *
  * Form FCD, "Fast C or D", is also designed for collation.
  * It allows to work on strings that are not necessarily normalized
  * with an algorithm (like in collation) that works under "canonical closure", i.e., it treats precomposed
  * characters and their decomposed equivalents the same.
  *
  * It is not a normalization form because it does not provide for uniqueness of representation. Multiple strings
  * may be canonically equivalent (their NFDs are identical) and may all conform to FCD without being identical
  * themselves.
  *
  * The form is defined such that the "raw decomposition", the recursive canonical decomposition of each character,
  * results in a string that is canonically ordered. This means that precomposed characters are allowed for as long
  * as their decompositions do not need canonical reordering.
  *
  * Its advantage for a process like collation is that all NFD and most NFC texts - and many unnormalized texts -
  * already conform to FCD and do not need to be normalized (NFD) for such a process. The FCD quick check will
  * return UNORM_YES for most strings in practice.
  *
  * unorm_normalize(UNORM_FCD) may be implemented with UNORM_NFD.
  *
  * For more details on FCD see the collation design document:
  * http://source.icu-project.org/repos/icu/icuhtml/trunk/design/collation/ICU_collation_design.htm
  *
  * ICU collation performs either NFD or FCD normalization automatically if normalization
  * is turned on for the collator object.
  * Beyond collation and string search, normalized strings may be useful for string equivalence comparisons,
  * transliteration/transcription, unique representations, etc.
  *
  * The W3C generally recommends to exchange texts in NFC.
  * Note also that most legacy character encodings use only precomposed forms and often do not
  * encode any combining marks by themselves. For conversion to such character encodings the
  * Unicode text needs to be normalized to NFC.
  * For more usage examples, see the Unicode Standard Annex.
  */
 /**
  * Constants for normalization modes.
  * @stable ICU 2.0
  */
 typedef enum {
   /** No decomposition/composition. @stable ICU 2.0 */
   UNORM_NONE = 1,
   /** Canonical decomposition. @stable ICU 2.0 */
   UNORM_NFD = 2,
   /** Compatibility decomposition. @stable ICU 2.0 */
   UNORM_NFKD = 3,
   /** Canonical decomposition followed by canonical composition. @stable ICU 2.0 */
   UNORM_NFC = 4,
   /** Default normalization. @stable ICU 2.0 */
   UNORM_DEFAULT = UNORM_NFC,
   /** Compatibility decomposition followed by canonical composition. @stable ICU 2.0 */
   UNORM_NFKC =5,
   /** "Fast C or D" form. @stable ICU 2.0 */
   UNORM_FCD = 6,
   /** One more than the highest normalization mode constant. @stable ICU 2.0 */
   UNORM_MODE_COUNT
 } UNormalizationMode;
 /**
  * Constants for options flags for normalization.
  * Use 0 for default options,
  * including normalization according to the Unicode version
  * that is currently supported by ICU (see u_getUnicodeVersion).
  * @stable ICU 2.6
  */
 enum {
     /**
      * Options bit set value to select Unicode 3.2 normalization
      * (except NormalizationCorrections).
      * At most one Unicode version can be selected at a time.
      * @stable ICU 2.6
      */
     UNORM_UNICODE_3_2=0x20
 };
 /**
  * Lowest-order bit number of unorm_compare() options bits corresponding to
  * normalization options bits.
  *
  * The options parameter for unorm_compare() uses most bits for
  * itself and for various comparison and folding flags.
  * The most significant bits, however, are shifted down and passed on
  * to the normalization implementation.
  * (That is, from unorm_compare(..., options, ...),
  * options>>UNORM_COMPARE_NORM_OPTIONS_SHIFT will be passed on to the
  * internal normalization functions.)
  *
  * @see unorm_compare
  * @stable ICU 2.6
  */
 #define UNORM_COMPARE_NORM_OPTIONS_SHIFT 20
 /**
  * Normalize a string.
  * The string will be normalized according the specified normalization mode
  * and options.
  * The source and result buffers must not be the same, nor overlap.
  *
  * @param source The string to normalize.
  * @param sourceLength The length of source, or -1 if NUL-terminated.
  * @param mode The normalization mode; one of UNORM_NONE,
  *             UNORM_NFD, UNORM_NFC, UNORM_NFKC, UNORM_NFKD, UNORM_DEFAULT.
  * @param options The normalization options, ORed together (0 for no options).
  * @param result A pointer to a buffer to receive the result string.
  *               The result string is NUL-terminated if possible.
  * @param resultLength The maximum size of result.
  * @param status A pointer to a UErrorCode to receive any errors.
  * @return The total buffer size needed; if greater than resultLength,
  *         the output was truncated, and the error code is set to U_BUFFER_OVERFLOW_ERROR.
  * @stable ICU 2.0
  */
 U_STABLE int32_t U_EXPORT2
 unorm_normalize(const UChar *source, int32_t sourceLength,
                 UNormalizationMode mode, int32_t options,
                 UChar *result, int32_t resultLength,
                 UErrorCode *status);
 /**
  * Performing quick check on a string, to quickly determine if the string is
  * in a particular normalization format.
  * Three types of result can be returned UNORM_YES, UNORM_NO or
  * UNORM_MAYBE. Result UNORM_YES indicates that the argument
  * string is in the desired normalized format, UNORM_NO determines that
  * argument string is not in the desired normalized format. A
  * UNORM_MAYBE result indicates that a more thorough check is required,
  * the user may have to put the string in its normalized form and compare the
  * results.
  *
  * @param source       string for determining if it is in a normalized format
  * @param sourcelength length of source to test, or -1 if NUL-terminated
  * @param mode         which normalization form to test for
  * @param status       a pointer to a UErrorCode to receive any errors
  * @return UNORM_YES, UNORM_NO or UNORM_MAYBE
  *
  * @see unorm_isNormalized
  * @stable ICU 2.0
  */
 U_STABLE UNormalizationCheckResult U_EXPORT2
 unorm_quickCheck(const UChar *source, int32_t sourcelength,
                  UNormalizationMode mode,
                  UErrorCode *status);
 /**
  * Performing quick check on a string; same as unorm_quickCheck but
  * takes an extra options parameter like most normalization functions.
  *
  * @param src        String that is to be tested if it is in a normalization format.
  * @param srcLength  Length of source to test, or -1 if NUL-terminated.
  * @param mode       Which normalization form to test for.
  * @param options    The normalization options, ORed together (0 for no options).
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return UNORM_YES, UNORM_NO or UNORM_MAYBE
  *
  * @see unorm_quickCheck
  * @see unorm_isNormalized
  * @stable ICU 2.6
  */
 U_STABLE UNormalizationCheckResult U_EXPORT2
 unorm_quickCheckWithOptions(const UChar *src, int32_t srcLength,
                             UNormalizationMode mode, int32_t options,
                             UErrorCode *pErrorCode);
 /**
  * Test if a string is in a given normalization form.
  * This is semantically equivalent to source.equals(normalize(source, mode)) .
  *
  * Unlike unorm_quickCheck(), this function returns a definitive result,
  * never a "maybe".
  * For NFD, NFKD, and FCD, both functions work exactly the same.
  * For NFC and NFKC where quickCheck may return "maybe", this function will
  * perform further tests to arrive at a TRUE/FALSE result.
  *
  * @param src        String that is to be tested if it is in a normalization format.
  * @param srcLength  Length of source to test, or -1 if NUL-terminated.
  * @param mode       Which normalization form to test for.
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return Boolean value indicating whether the source string is in the
  *         "mode" normalization form.
  *
  * @see unorm_quickCheck
  * @stable ICU 2.2
  */
 U_STABLE UBool U_EXPORT2
 unorm_isNormalized(const UChar *src, int32_t srcLength,
                    UNormalizationMode mode,
                    UErrorCode *pErrorCode);
 /**
  * Test if a string is in a given normalization form; same as unorm_isNormalized but
  * takes an extra options parameter like most normalization functions.
  *
  * @param src        String that is to be tested if it is in a normalization format.
  * @param srcLength  Length of source to test, or -1 if NUL-terminated.
  * @param mode       Which normalization form to test for.
  * @param options    The normalization options, ORed together (0 for no options).
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return Boolean value indicating whether the source string is in the
  *         "mode/options" normalization form.
  *
  * @see unorm_quickCheck
  * @see unorm_isNormalized
  * @stable ICU 2.6
  */
 U_STABLE UBool U_EXPORT2
 unorm_isNormalizedWithOptions(const UChar *src, int32_t srcLength,
                               UNormalizationMode mode, int32_t options,
                               UErrorCode *pErrorCode);
 /**
  * Iterative normalization forward.
  * This function (together with unorm_previous) is somewhat
  * similar to the C++ Normalizer class (see its non-static functions).
  *
  * Iterative normalization is useful when only a small portion of a longer
  * string/text needs to be processed.
  *
  * For example, the likelihood may be high that processing the first 10% of some
  * text will be sufficient to find certain data.
  * Another example: When one wants to concatenate two normalized strings and get a
  * normalized result, it is much more efficient to normalize just a small part of
  * the result around the concatenation place instead of re-normalizing everything.
  *
  * The input text is an instance of the C character iteration API UCharIterator.
  * It may wrap around a simple string, a CharacterIterator, a Replaceable, or any
  * other kind of text object.
  *
  * If a buffer overflow occurs, then the caller needs to reset the iterator to the
  * old index and call the function again with a larger buffer - if the caller cares
  * for the actual output.
  * Regardless of the output buffer, the iterator will always be moved to the next
  * normalization boundary.
  *
  * This function (like unorm_previous) serves two purposes:
  *
  * 1) To find the next boundary so that the normalization of the part of the text
  * from the current position to that boundary does not affect and is not affected
  * by the part of the text beyond that boundary.
  *
  * 2) To normalize the text up to the boundary.
  *
  * The second step is optional, per the doNormalize parameter.
  * It is omitted for operations like string concatenation, where the two adjacent
  * string ends need to be normalized together.
  * In such a case, the output buffer will just contain a copy of the text up to the
  * boundary.
  *
  * pNeededToNormalize is an output-only parameter. Its output value is only defined
  * if normalization was requested (doNormalize) and successful (especially, no
  * buffer overflow).
  * It is useful for operations like a normalizing transliterator, where one would
  * not want to replace a piece of text if it is not modified.
  *
  * If doNormalize==TRUE and pNeededToNormalize!=NULL then *pNeeded... is set TRUE
  * if the normalization was necessary.
  *
  * If doNormalize==FALSE then *pNeededToNormalize will be set to FALSE.
  *
  * If the buffer overflows, then *pNeededToNormalize will be undefined;
  * essentially, whenever U_FAILURE is true (like in buffer overflows), this result
  * will be undefined.
  *
  * @param src The input text in the form of a C character iterator.
  * @param dest The output buffer; can be NULL if destCapacity==0 for pure preflighting.
  * @param destCapacity The number of UChars that fit into dest.
  * @param mode The normalization mode.
  * @param options The normalization options, ORed together (0 for no options).
  * @param doNormalize Indicates if the source text up to the next boundary
  *                    is to be normalized (TRUE) or just copied (FALSE).
  * @param pNeededToNormalize Output flag indicating if the normalization resulted in
  *                           different text from the input.
  *                           Not defined if an error occurs including buffer overflow.
  *                           Always FALSE if !doNormalize.
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return Length of output (number of UChars) when successful or buffer overflow.
  *
  * @see unorm_previous
  * @see unorm_normalize
  *
  * @stable ICU 2.1
  */
 U_STABLE int32_t U_EXPORT2
 unorm_next(UCharIterator *src,
            UChar *dest, int32_t destCapacity,
            UNormalizationMode mode, int32_t options,
            UBool doNormalize, UBool *pNeededToNormalize,
            UErrorCode *pErrorCode);
 /**
  * Iterative normalization backward.
  * This function (together with unorm_next) is somewhat
  * similar to the C++ Normalizer class (see its non-static functions).
  * For all details see unorm_next.
  *
  * @param src The input text in the form of a C character iterator.
  * @param dest The output buffer; can be NULL if destCapacity==0 for pure preflighting.
  * @param destCapacity The number of UChars that fit into dest.
  * @param mode The normalization mode.
  * @param options The normalization options, ORed together (0 for no options).
  * @param doNormalize Indicates if the source text up to the next boundary
  *                    is to be normalized (TRUE) or just copied (FALSE).
  * @param pNeededToNormalize Output flag indicating if the normalization resulted in
  *                           different text from the input.
  *                           Not defined if an error occurs including buffer overflow.
  *                           Always FALSE if !doNormalize.
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return Length of output (number of UChars) when successful or buffer overflow.
  *
  * @see unorm_next
  * @see unorm_normalize
  *
  * @stable ICU 2.1
  */
 U_STABLE int32_t U_EXPORT2
 unorm_previous(UCharIterator *src,
                UChar *dest, int32_t destCapacity,
                UNormalizationMode mode, int32_t options,
                UBool doNormalize, UBool *pNeededToNormalize,
                UErrorCode *pErrorCode);
 /**
  * Concatenate normalized strings, making sure that the result is normalized as well.
  *
  * If both the left and the right strings are in
  * the normalization form according to "mode/options",
  * then the result will be
  *
  * \code
  *     dest=normalize(left+right, mode, options)
  * \endcode
  *
  * With the input strings already being normalized,
  * this function will use unorm_next() and unorm_previous()
  * to find the adjacent end pieces of the input strings.
  * Only the concatenation of these end pieces will be normalized and
  * then concatenated with the remaining parts of the input strings.
  *
  * It is allowed to have dest==left to avoid copying the entire left string.
  *
  * @param left Left source string, may be same as dest.
  * @param leftLength Length of left source string, or -1 if NUL-terminated.
  * @param right Right source string. Must not be the same as dest, nor overlap.
  * @param rightLength Length of right source string, or -1 if NUL-terminated.
  * @param dest The output buffer; can be NULL if destCapacity==0 for pure preflighting.
  * @param destCapacity The number of UChars that fit into dest.
  * @param mode The normalization mode.
  * @param options The normalization options, ORed together (0 for no options).
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return Length of output (number of UChars) when successful or buffer overflow.
  *
  * @see unorm_normalize
  * @see unorm_next
  * @see unorm_previous
  *
  * @stable ICU 2.1
  */
 U_STABLE int32_t U_EXPORT2
 unorm_concatenate(const UChar *left, int32_t leftLength,
                   const UChar *right, int32_t rightLength,
                   UChar *dest, int32_t destCapacity,
                   UNormalizationMode mode, int32_t options,
                   UErrorCode *pErrorCode);
 /**
  * Option bit for unorm_compare:
  * Both input strings are assumed to fulfill FCD conditions.
  * @stable ICU 2.2
  */
 #define UNORM_INPUT_IS_FCD          0x20000
 /**
  * Option bit for unorm_compare:
  * Perform case-insensitive comparison.
  * @stable ICU 2.2
  */
 #define U_COMPARE_IGNORE_CASE       0x10000
 #ifndef U_COMPARE_CODE_POINT_ORDER
 /* see also unistr.h and ustring.h */
 /**
  * Option bit for u_strCaseCompare, u_strcasecmp, unorm_compare, etc:
  * Compare strings in code point order instead of code unit order.
  * @stable ICU 2.2
  */
 #define U_COMPARE_CODE_POINT_ORDER  0x8000
 #endif
 /**
  * Compare two strings for canonical equivalence.
  * Further options include case-insensitive comparison and
  * code point order (as opposed to code unit order).
  *
  * Canonical equivalence between two strings is defined as their normalized
  * forms (NFD or NFC) being identical.
  * This function compares strings incrementally instead of normalizing
  * (and optionally case-folding) both strings entirely,
  * improving performance significantly.
  *
  * Bulk normalization is only necessary if the strings do not fulfill the FCD
  * conditions. Only in this case, and only if the strings are relatively long,
  * is memory allocated temporarily.
  * For FCD strings and short non-FCD strings there is no memory allocation.
  *
  * Semantically, this is equivalent to
  *   strcmp[CodePointOrder](NFD(foldCase(NFD(s1))), NFD(foldCase(NFD(s2))))
  * where code point order and foldCase are all optional.
  *
  * UAX 21 2.5 Caseless Matching specifies that for a canonical caseless match
  * the case folding must be performed first, then the normalization.
  *
  * @param s1 First source string.
  * @param length1 Length of first source string, or -1 if NUL-terminated.
  *
  * @param s2 Second source string.
  * @param length2 Length of second source string, or -1 if NUL-terminated.
  *
  * @param options A bit set of options:
  *   - U_FOLD_CASE_DEFAULT or 0 is used for default options:
  *     Case-sensitive comparison in code unit order, and the input strings
  *     are quick-checked for FCD.
  *
  *   - UNORM_INPUT_IS_FCD
  *     Set if the caller knows that both s1 and s2 fulfill the FCD conditions.
  *     If not set, the function will quickCheck for FCD
  *     and normalize if necessary.
  *
  *   - U_COMPARE_CODE_POINT_ORDER
  *     Set to choose code point order instead of code unit order
  *     (see u_strCompare for details).
  *
  *   - U_COMPARE_IGNORE_CASE
  *     Set to compare strings case-insensitively using case folding,
  *     instead of case-sensitively.
  *     If set, then the following case folding options are used.
  *
  *   - Options as used with case-insensitive comparisons, currently:
  *
  *   - U_FOLD_CASE_EXCLUDE_SPECIAL_I
  *    (see u_strCaseCompare for details)
  *
  *   - regular normalization options shifted left by UNORM_COMPARE_NORM_OPTIONS_SHIFT
  *
  * @param pErrorCode ICU error code in/out parameter.
  *                   Must fulfill U_SUCCESS before the function call.
  * @return <0 or 0 or >0 as usual for string comparisons
  *
  * @see unorm_normalize
  * @see UNORM_FCD
  * @see u_strCompare
  * @see u_strCaseCompare
  *
  * @stable ICU 2.2
  */
 U_STABLE int32_t U_EXPORT2
 unorm_compare(const UChar *s1, int32_t length1,
               const UChar *s2, int32_t length2,
               uint32_t options,
               UErrorCode *pErrorCode);
 #endif /* #if !UCONFIG_NO_NORMALIZATION */
 #endif

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intl/icu/source/common/unicode/unorm.h@6474c204b198 (annotated)

intl/icu/source/common/unicode/unorm.h