scuffed-code/icu4c/source/common/unicode/normlzr.h

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/*
********************************************************************
* COPYRIGHT:
* Copyright (c) 1996-2004, International Business Machines Corporation and
* others. All Rights Reserved.
********************************************************************
*/
#ifndef NORMLZR_H
#define NORMLZR_H
#include "unicode/utypes.h"
#if !UCONFIG_NO_NORMALIZATION
#include "unicode/uobject.h"
#include "unicode/unistr.h"
#include "unicode/chariter.h"
#include "unicode/unorm.h"
struct UCharIterator;
typedef struct UCharIterator UCharIterator; /**< C typedef for struct UCharIterator. @stable ICU 2.1 */
U_NAMESPACE_BEGIN
/**
* \brief C++ API: Unicode Normalization
*
* The Normalizer class consists of two parts:
* - static functions that normalize strings or test if strings are normalized
* - a Normalizer object is an iterator that takes any kind of text and
* provides iteration over its normalized form
*
* The Normalizer class is not suitable for subclassing.
*
* The static functions are basically wrappers around the C implementation,
* using UnicodeString instead of UChar*.
* For basic information about normalization forms and details about the C API
* please see the documentation in unorm.h.
*
* The iterator API with the Normalizer constructors and the non-static functions
* uses a CharacterIterator as input. It is possible to pass a string which
* is then internally wrapped in a CharacterIterator.
* The input text is not normalized all at once, but incrementally where needed
* (providing efficient random access).
* This allows to pass in a large text but spend only a small amount of time
* normalizing a small part of that text.
* However, if the entire text is normalized, then the iterator will be
* slower than normalizing the entire text at once and iterating over the result.
* A possible use of the Normalizer iterator is also to report an index into the
* original text that is close to where the normalized characters come from.
*
* <em>Important:</em> The iterator API was cleaned up significantly for ICU 2.0.
* The earlier implementation reported the getIndex() inconsistently,
* and previous() could not be used after setIndex(), next(), first(), and current().
*
* Normalizer allows to start normalizing from anywhere in the input text by
* calling setIndexOnly(), first(), or last().
* Without calling any of these, the iterator will start at the beginning of the text.
*
* At any time, next() returns the next normalized code point (UChar32),
* with post-increment semantics (like CharacterIterator::next32PostInc()).
* previous() returns the previous normalized code point (UChar32),
* with pre-decrement semantics (like CharacterIterator::previous32()).
*
* current() returns the current code point
* (respectively the one at the newly set index) without moving
* the getIndex(). Note that if the text at the current position
* needs to be normalized, then these functions will do that.
* (This is why current() is not const.)
* It is more efficient to call setIndexOnly() instead, which does not
* normalize.
*
* getIndex() always refers to the position in the input text where the normalized
* code points are returned from. It does not always change with each returned
* code point.
* The code point that is returned from any of the functions
* corresponds to text at or after getIndex(), according to the
* function's iteration semantics (post-increment or pre-decrement).
*
* next() returns a code point from at or after the getIndex()
* from before the next() call. After the next() call, the getIndex()
* might have moved to where the next code point will be returned from
* (from a next() or current() call).
* This is semantically equivalent to array access with array[index++]
* (post-increment semantics).
*
* previous() returns a code point from at or after the getIndex()
* from after the previous() call.
* This is semantically equivalent to array access with array[--index]
* (pre-decrement semantics).
*
* Internally, the Normalizer iterator normalizes a small piece of text
* starting at the getIndex() and ending at a following "safe" index.
* The normalized results is stored in an internal string buffer, and
* the code points are iterated from there.
* With multiple iteration calls, this is repeated until the next piece
* of text needs to be normalized, and the getIndex() needs to be moved.
*
* The following "safe" index, the internal buffer, and the secondary
* iteration index into that buffer are not exposed on the API.
* This also means that it is currently not practical to return to
* a particular, arbitrary position in the text because one would need to
* know, and be able to set, in addition to the getIndex(), at least also the
* current index into the internal buffer.
* It is currently only possible to observe when getIndex() changes
* (with careful consideration of the iteration semantics),
* at which time the internal index will be 0.
* For example, if getIndex() is different after next() than before it,
* then the internal index is 0 and one can return to this getIndex()
* later with setIndexOnly().
*
* @author Laura Werner, Mark Davis, Markus Scherer
* @stable ICU 2.0
*/
class U_COMMON_API Normalizer : public UObject {
public:
/**
* If DONE is returned from an iteration function that returns a code point,
* then there are no more normalization results available.
* @stable ICU 2.0
*/
enum {
DONE=0xffff
};
// Constructors
/**
* Creates a new <code>Normalizer</code> object for iterating over the
* normalized form of a given string.
* <p>
* @param str The string to be normalized. The normalization
* will start at the beginning of the string.
*
* @param mode The normalization mode.
* @stable ICU 2.0
*/
Normalizer(const UnicodeString& str, UNormalizationMode mode);
/**
* Creates a new <code>Normalizer</code> object for iterating over the
* normalized form of a given string.
* <p>
* @param str The string to be normalized. The normalization
* will start at the beginning of the string.
*
* @param length Length of the string, or -1 if NUL-terminated.
* @param mode The normalization mode.
* @stable ICU 2.0
*/
Normalizer(const UChar* str, int32_t length, UNormalizationMode mode);
/**
* Creates a new <code>Normalizer</code> object for iterating over the
* normalized form of the given text.
* <p>
* @param iter The input text to be normalized. The normalization
* will start at the beginning of the string.
*
* @param mode The normalization mode.
* @stable ICU 2.0
*/
Normalizer(const CharacterIterator& iter, UNormalizationMode mode);
/**
* Copy constructor.
* @param copy The object to be copied.
* @stable ICU 2.0
*/
Normalizer(const Normalizer& copy);
/**
* Destructor
* @stable ICU 2.0
*/
virtual ~Normalizer();
//-------------------------------------------------------------------------
// Static utility methods
//-------------------------------------------------------------------------
/**
* Normalizes a <code>UnicodeString</code> according to the specified normalization mode.
* This is a wrapper for unorm_normalize(), using UnicodeString's.
*
* The <code>options</code> parameter specifies which optional
* <code>Normalizer</code> features are to be enabled for this operation.
*
* @param source the input string to be normalized.
* @param mode the normalization mode
* @param options the optional features to be enabled (0 for no options)
* @param result The normalized string (on output).
* @param status The error code.
* @stable ICU 2.0
*/
static void U_EXPORT2 normalize(const UnicodeString& source,
UNormalizationMode mode, int32_t options,
UnicodeString& result,
UErrorCode &status);
/**
* Compose a <code>UnicodeString</code>.
* This is equivalent to normalize() with mode UNORM_NFC or UNORM_NFKC.
* This is a wrapper for unorm_normalize(), using UnicodeString's.
*
* The <code>options</code> parameter specifies which optional
* <code>Normalizer</code> features are to be enabled for this operation.
*
* @param source the string to be composed.
* @param compat Perform compatibility decomposition before composition.
* If this argument is <code>FALSE</code>, only canonical
* decomposition will be performed.
* @param options the optional features to be enabled (0 for no options)
* @param result The composed string (on output).
* @param status The error code.
* @stable ICU 2.0
*/
static void U_EXPORT2 compose(const UnicodeString& source,
UBool compat, int32_t options,
UnicodeString& result,
UErrorCode &status);
/**
* Static method to decompose a <code>UnicodeString</code>.
* This is equivalent to normalize() with mode UNORM_NFD or UNORM_NFKD.
* This is a wrapper for unorm_normalize(), using UnicodeString's.
*
* The <code>options</code> parameter specifies which optional
* <code>Normalizer</code> features are to be enabled for this operation.
*
* @param source the string to be decomposed.
* @param compat Perform compatibility decomposition.
* If this argument is <code>FALSE</code>, only canonical
* decomposition will be performed.
* @param options the optional features to be enabled (0 for no options)
* @param result The decomposed string (on output).
* @param status The error code.
* @stable ICU 2.0
*/
static void U_EXPORT2 decompose(const UnicodeString& source,
UBool compat, int32_t options,
UnicodeString& result,
UErrorCode &status);
/**
* Performing quick check on a string, to quickly determine if the string is
* in a particular normalization format.
* This is a wrapper for unorm_quickCheck(), using a UnicodeString.
*
* 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 mode normalization format
* @param status A reference to a UErrorCode to receive any errors
* @return UNORM_YES, UNORM_NO or UNORM_MAYBE
*
* @see isNormalized
* @stable ICU 2.0
*/
static inline UNormalizationCheckResult
quickCheck(const UnicodeString &source, UNormalizationMode mode, UErrorCode &status);
/**
* Performing quick check on a string; same as the other version of quickCheck
* but takes an extra options parameter like most normalization functions.
*
* @param source string for determining if it is in a normalized format
* @param mode normalization format
* @param options the optional features to be enabled (0 for no options)
* @param status A reference to a UErrorCode to receive any errors
* @return UNORM_YES, UNORM_NO or UNORM_MAYBE
*
* @see isNormalized
* @draft ICU 2.6
*/
static inline UNormalizationCheckResult
quickCheck(const UnicodeString &source, UNormalizationMode mode, int32_t options, UErrorCode &status);
/**
* 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 mode Which normalization form to test for.
* @param errorCode 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 quickCheck
* @stable ICU 2.2
*/
static inline UBool
isNormalized(const UnicodeString &src, UNormalizationMode mode, UErrorCode &errorCode);
/**
* Test if a string is in a given normalization form; same as the other version of 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 mode Which normalization form to test for.
* @param options the optional features to be enabled (0 for no options)
* @param errorCode 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 quickCheck
* @draft ICU 2.6
*/
static inline UBool
isNormalized(const UnicodeString &src, UNormalizationMode mode, int32_t options, UErrorCode &errorCode);
/**
* 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
*
* For details see unorm_concatenate in unorm.h.
*
* @param left Left source string.
* @param right Right source string.
* @param result The output string.
* @param mode The normalization mode.
* @param options A bit set of normalization options.
* @param errorCode ICU error code in/out parameter.
* Must fulfill U_SUCCESS before the function call.
* @return result
*
* @see unorm_concatenate
* @see normalize
* @see unorm_next
* @see unorm_previous
*
* @stable ICU 2.1
*/
static UnicodeString &
U_EXPORT2 concatenate(UnicodeString &left, UnicodeString &right,
UnicodeString &result,
UNormalizationMode mode, int32_t options,
UErrorCode &errorCode);
/**
* 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(s1)), NFD(foldCase(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 s2 Second source string.
*
* @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 errorCode 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_compare
* @see normalize
* @see UNORM_FCD
* @see u_strCompare
* @see u_strCaseCompare
*
* @stable ICU 2.2
*/
static inline int32_t
compare(const UnicodeString &s1, const UnicodeString &s2,
uint32_t options,
UErrorCode &errorCode);
//-------------------------------------------------------------------------
// Iteration API
//-------------------------------------------------------------------------
/**
* Return the current character in the normalized text.
* current() may need to normalize some text at getIndex().
* The getIndex() is not changed.
*
* @return the current normalized code point
* @stable ICU 2.0
*/
UChar32 current(void);
/**
* Return the first character in the normalized text.
* This is equivalent to setIndexOnly(startIndex()) followed by next().
* (Post-increment semantics.)
*
* @return the first normalized code point
* @stable ICU 2.0
*/
UChar32 first(void);
/**
* Return the last character in the normalized text.
* This is equivalent to setIndexOnly(endIndex()) followed by previous().
* (Pre-decrement semantics.)
*
* @return the last normalized code point
* @stable ICU 2.0
*/
UChar32 last(void);
/**
* Return the next character in the normalized text.
* (Post-increment semantics.)
* If the end of the text has already been reached, DONE is returned.
* The DONE value could be confused with a U+FFFF non-character code point
* in the text. If this is possible, you can test getIndex()<endIndex()
* before calling next(), or (getIndex()<endIndex() || last()!=DONE)
* after calling next(). (Calling last() will change the iterator state!)
*
* The C API unorm_next() is more efficient and does not have this ambiguity.
*
* @return the next normalized code point
* @stable ICU 2.0
*/
UChar32 next(void);
/**
* Return the previous character in the normalized text and decrement.
* (Pre-decrement semantics.)
* If the beginning of the text has already been reached, DONE is returned.
* The DONE value could be confused with a U+FFFF non-character code point
* in the text. If this is possible, you can test
* (getIndex()>startIndex() || first()!=DONE). (Calling first() will change
* the iterator state!)
*
* The C API unorm_previous() is more efficient and does not have this ambiguity.
*
* @return the previous normalized code point
* @stable ICU 2.0
*/
UChar32 previous(void);
/**
* Set the iteration position in the input text that is being normalized,
* without any immediate normalization.
* After setIndexOnly(), getIndex() will return the same index that is
* specified here.
*
* @param index the desired index in the input text.
* @stable ICU 2.0
*/
void setIndexOnly(int32_t index);
/**
* Reset the index to the beginning of the text.
* This is equivalent to setIndexOnly(startIndex)).
* @stable ICU 2.0
*/
void reset(void);
/**
* Retrieve the current iteration position in the input text that is
* being normalized.
*
* A following call to next() will return a normalized code point from
* the input text at or after this index.
*
* After a call to previous(), getIndex() will point at or before the
* position in the input text where the normalized code point
* was returned from with previous().
*
* @return the current index in the input text
* @stable ICU 2.0
*/
int32_t getIndex(void) const;
/**
* Retrieve the index of the start of the input text. This is the begin index
* of the <code>CharacterIterator</code> or the start (i.e. index 0) of the string
* over which this <code>Normalizer</code> is iterating.
*
* @return the smallest index in the input text where the Normalizer operates
* @stable ICU 2.0
*/
int32_t startIndex(void) const;
/**
* Retrieve the index of the end of the input text. This is the end index
* of the <code>CharacterIterator</code> or the length of the string
* over which this <code>Normalizer</code> is iterating.
* This end index is exclusive, i.e., the Normalizer operates only on characters
* before this index.
*
* @return the first index in the input text where the Normalizer does not operate
* @stable ICU 2.0
*/
int32_t endIndex(void) const;
/**
* Returns TRUE when both iterators refer to the same character in the same
* input text.
*
* @param that a Normalizer object to compare this one to
* @return comparison result
* @stable ICU 2.0
*/
UBool operator==(const Normalizer& that) const;
/**
* Returns FALSE when both iterators refer to the same character in the same
* input text.
*
* @param that a Normalizer object to compare this one to
* @return comparison result
* @stable ICU 2.0
*/
inline UBool operator!=(const Normalizer& that) const;
/**
* Returns a pointer to a new Normalizer that is a clone of this one.
* The caller is responsible for deleting the new clone.
* @return a pointer to a new Normalizer
* @stable ICU 2.0
*/
Normalizer* clone(void) const;
/**
* Generates a hash code for this iterator.
*
* @return the hash code
* @stable ICU 2.0
*/
int32_t hashCode(void) const;
//-------------------------------------------------------------------------
// Property access methods
//-------------------------------------------------------------------------
/**
* Set the normalization mode for this object.
* <p>
* <b>Note:</b>If the normalization mode is changed while iterating
* over a string, calls to {@link #next() } and {@link #previous() } may
* return previously buffers characters in the old normalization mode
* until the iteration is able to re-sync at the next base character.
* It is safest to call {@link #setIndexOnly }, {@link #reset() },
* {@link #setText }, {@link #first() },
* {@link #last() }, etc. after calling <code>setMode</code>.
* <p>
* @param newMode the new mode for this <code>Normalizer</code>.
* @see #getUMode
* @stable ICU 2.0
*/
void setMode(UNormalizationMode newMode);
/**
* Return the normalization mode for this object.
*
* This is an unusual name because there used to be a getMode() that
* returned a different type.
*
* @return the mode for this <code>Normalizer</code>
* @see #setMode
* @stable ICU 2.0
*/
UNormalizationMode getUMode(void) const;
/**
* Set options that affect this <code>Normalizer</code>'s operation.
* Options do not change the basic composition or decomposition operation
* that is being performed, but they control whether
* certain optional portions of the operation are done.
* Currently the only available option is obsolete.
*
* It is possible to specify multiple options that are all turned on or off.
*
* @param option the option(s) whose value is/are to be set.
* @param value the new setting for the option. Use <code>TRUE</code> to
* turn the option(s) on and <code>FALSE</code> to turn it/them off.
*
* @see #getOption
* @stable ICU 2.0
*/
void setOption(int32_t option,
UBool value);
/**
* Determine whether an option is turned on or off.
* If multiple options are specified, then the result is TRUE if any
* of them are set.
* <p>
* @param option the option(s) that are to be checked
* @return TRUE if any of the option(s) are set
* @see #setOption
* @stable ICU 2.0
*/
UBool getOption(int32_t option) const;
/**
* Set the input text over which this <code>Normalizer</code> will iterate.
* The iteration position is set to the beginning.
*
* @param newText a string that replaces the current input text
* @param status a UErrorCode
* @stable ICU 2.0
*/
void setText(const UnicodeString& newText,
UErrorCode &status);
/**
* Set the input text over which this <code>Normalizer</code> will iterate.
* The iteration position is set to the beginning.
*
* @param newText a CharacterIterator object that replaces the current input text
* @param status a UErrorCode
* @stable ICU 2.0
*/
void setText(const CharacterIterator& newText,
UErrorCode &status);
/**
* Set the input text over which this <code>Normalizer</code> will iterate.
* The iteration position is set to the beginning.
*
* @param newText a string that replaces the current input text
* @param length the length of the string, or -1 if NUL-terminated
* @param status a UErrorCode
* @stable ICU 2.0
*/
void setText(const UChar* newText,
int32_t length,
UErrorCode &status);
/**
* Copies the input text into the UnicodeString argument.
*
* @param result Receives a copy of the text under iteration.
* @stable ICU 2.0
*/
void getText(UnicodeString& result);
/**
* ICU "poor man's RTTI", returns a UClassID for this class.
* @returns a UClassID for this class.
* @stable ICU 2.2
*/
static UClassID U_EXPORT2 getStaticClassID();
/**
* ICU "poor man's RTTI", returns a UClassID for the actual class.
* @return a UClassID for the actual class.
* @stable ICU 2.2
*/
virtual UClassID getDynamicClassID() const;
private:
//-------------------------------------------------------------------------
// Private functions
//-------------------------------------------------------------------------
Normalizer(); // default constructor not implemented
Normalizer &operator=(const Normalizer &that); // assignment operator not implemented
// Private utility methods for iteration
// For documentation, see the source code
UBool nextNormalize();
UBool previousNormalize();
void init(CharacterIterator *iter);
void clearBuffer(void);
//-------------------------------------------------------------------------
// Private data
//-------------------------------------------------------------------------
UNormalizationMode fUMode;
int32_t fOptions;
// The input text and our position in it
UCharIterator *text;
// The normalization buffer is the result of normalization
// of the source in [currentIndex..nextIndex[ .
int32_t currentIndex, nextIndex;
// A buffer for holding intermediate results
UnicodeString buffer;
int32_t bufferPos;
};
//-------------------------------------------------------------------------
// Inline implementations
//-------------------------------------------------------------------------
inline UBool
Normalizer::operator!= (const Normalizer& other) const
{ return ! operator==(other); }
inline UNormalizationCheckResult
Normalizer::quickCheck(const UnicodeString& source,
UNormalizationMode mode,
UErrorCode &status) {
if(U_FAILURE(status)) {
return UNORM_MAYBE;
}
return unorm_quickCheck(source.getBuffer(), source.length(),
mode, &status);
}
inline UNormalizationCheckResult
Normalizer::quickCheck(const UnicodeString& source,
UNormalizationMode mode, int32_t options,
UErrorCode &status) {
if(U_FAILURE(status)) {
return UNORM_MAYBE;
}
return unorm_quickCheckWithOptions(source.getBuffer(), source.length(),
mode, options, &status);
}
inline UBool
Normalizer::isNormalized(const UnicodeString& source,
UNormalizationMode mode,
UErrorCode &status) {
if(U_FAILURE(status)) {
return FALSE;
}
return unorm_isNormalized(source.getBuffer(), source.length(),
mode, &status);
}
inline UBool
Normalizer::isNormalized(const UnicodeString& source,
UNormalizationMode mode, int32_t options,
UErrorCode &status) {
if(U_FAILURE(status)) {
return FALSE;
}
return unorm_isNormalizedWithOptions(source.getBuffer(), source.length(),
mode, options, &status);
}
inline int32_t
Normalizer::compare(const UnicodeString &s1, const UnicodeString &s2,
uint32_t options,
UErrorCode &errorCode) {
// all argument checking is done in unorm_compare
return unorm_compare(s1.getBuffer(), s1.length(),
s2.getBuffer(), s2.length(),
options,
&errorCode);
}
U_NAMESPACE_END
#endif /* #if !UCONFIG_NO_NORMALIZATION */
#endif // NORMLZR_H