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diff --git a/intl/icu/source/common/unicode/unorm.h b/intl/icu/source/common/unicode/unorm.h new file mode 100644 index 000000000..f527c263f --- /dev/null +++ b/intl/icu/source/common/unicode/unorm.h @@ -0,0 +1,472 @@ +// Copyright (C) 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +******************************************************************************* +* Copyright (c) 1996-2016, 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 + * + * Old Unicode normalization API. + * + * This API has been replaced by the unorm2.h API and is only available + * for backward compatibility.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(). + * Its declaration has been moved to unorm2.h. + * + * <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. + */ + +// Do not conditionalize the following enum with #ifndef U_HIDE_DEPRECATED_API, +// it is needed for layout of Normalizer object. +/** + * Constants for normalization modes. + * @deprecated ICU 56 Use unorm2.h instead. + */ +typedef enum { + /** No decomposition/composition. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_NONE = 1, + /** Canonical decomposition. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_NFD = 2, + /** Compatibility decomposition. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_NFKD = 3, + /** Canonical decomposition followed by canonical composition. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_NFC = 4, + /** Default normalization. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_DEFAULT = UNORM_NFC, + /** Compatibility decomposition followed by canonical composition. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_NFKC =5, + /** "Fast C or D" form. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_FCD = 6, + + /** One more than the highest normalization mode constant. @deprecated ICU 56 Use unorm2.h instead. */ + UNORM_MODE_COUNT +} UNormalizationMode; + +#ifndef U_HIDE_DEPRECATED_API + +/** + * 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). + * @deprecated ICU 56 Use unorm2.h instead. + */ +enum { + /** + * Options bit set value to select Unicode 3.2 normalization + * (except NormalizationCorrections). + * At most one Unicode version can be selected at a time. + * @deprecated ICU 56 Use unorm2.h instead. + */ + 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 + * @deprecated ICU 56 Use unorm2.h instead. + */ +#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. + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * + * @deprecated ICU 56 Use unorm2.h instead. + */ +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 + * + * @deprecated ICU 56 Use unorm2.h instead. + */ +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); + +#endif /* U_HIDE_DEPRECATED_API */ +#endif /* #if !UCONFIG_NO_NORMALIZATION */ +#endif |