Check in the pristine copy of ICU 4.6...

icu46/source/i18n/unicode/ucoleitr.h

+/*
+*******************************************************************************
+*   Copyright (C) 2001-2009, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*******************************************************************************
+*
+* File ucoleitr.cpp
+*
+* Modification History:
+*
+* Date        Name        Description
+* 02/15/2001  synwee      Modified all methods to process its own function 
+*                         instead of calling the equivalent c++ api (coleitr.h)
+*******************************************************************************/
+
+#ifndef UCOLEITR_H
+#define UCOLEITR_H
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_COLLATION
+
+/**  
+ * This indicates an error has occured during processing or if no more CEs is 
+ * to be returned.
+ * @stable ICU 2.0
+ */
+#define UCOL_NULLORDER        ((int32_t)0xFFFFFFFF)
+
+/**  
+ * This indicates an error has occured during processing or there are no more CEs 
+ * to be returned.
+ *
+ * @internal
+ */
+#define UCOL_PROCESSED_NULLORDER        ((int64_t)U_INT64_MAX)
+
+#include "unicode/ucol.h"
+
+/** 
+ * The UCollationElements struct.
+ * For usage in C programs.
+ * @stable ICU 2.0
+ */
+typedef struct UCollationElements UCollationElements;
+
+/**
+ * \file
+ * \brief C API: UCollationElements
+ *
+ * The UCollationElements API is used as an iterator to walk through each 
+ * character of an international string. Use the iterator to return the
+ * ordering priority of the positioned character. The ordering priority of a 
+ * character, which we refer to as a key, defines how a character is collated 
+ * in the given collation object.
+ * For example, consider the following in Spanish:
+ * <pre>
+ * .       "ca" -> the first key is key('c') and second key is key('a').
+ * .       "cha" -> the first key is key('ch') and second key is key('a').
+ * </pre>
+ * And in German,
+ * <pre>
+ * .       "<ae ligature>b"-> the first key is key('a'), the second key is key('e'), and
+ * .       the third key is key('b').
+ * </pre>
+ * <p>Example of the iterator usage: (without error checking)
+ * <pre>
+ * .  void CollationElementIterator_Example()
+ * .  {
+ * .      UChar *s;
+ * .      t_int32 order, primaryOrder;
+ * .      UCollationElements *c;
+ * .      UCollatorOld *coll;
+ * .      UErrorCode success = U_ZERO_ERROR;
+ * .      s=(UChar*)malloc(sizeof(UChar) * (strlen("This is a test")+1) );
+ * .      u_uastrcpy(s, "This is a test");
+ * .      coll = ucol_open(NULL, &success);
+ * .      c = ucol_openElements(coll, str, u_strlen(str), &status);
+ * .      order = ucol_next(c, &success);
+ * .      ucol_reset(c);
+ * .      order = ucol_prev(c, &success);
+ * .      free(s);
+ * .      ucol_close(coll);
+ * .      ucol_closeElements(c);
+ * .  }
+ * </pre>
+ * <p>
+ * ucol_next() returns the collation order of the next.
+ * ucol_prev() returns the collation order of the previous character.
+ * The Collation Element Iterator moves only in one direction between calls to
+ * ucol_reset. That is, ucol_next() and ucol_prev can not be inter-used. 
+ * Whenever ucol_prev is to be called after ucol_next() or vice versa, 
+ * ucol_reset has to be called first to reset the status, shifting pointers to 
+ * either the end or the start of the string. Hence at the next call of 
+ * ucol_prev or ucol_next, the first or last collation order will be returned. 
+ * If a change of direction is done without a ucol_reset, the result is 
+ * undefined.
+ * The result of a forward iterate (ucol_next) and reversed result of the  
+ * backward iterate (ucol_prev) on the same string are equivalent, if 
+ * collation orders with the value UCOL_IGNORABLE are ignored.
+ * Character based on the comparison level of the collator.  A collation order 
+ * consists of primary order, secondary order and tertiary order.  The data 
+ * type of the collation order is <strong>t_int32</strong>. 
+ *
+ * @see UCollator
+ */
+
+/**
+ * Open the collation elements for a string.
+ *
+ * @param coll The collator containing the desired collation rules.
+ * @param text The text to iterate over.
+ * @param textLength The number of characters in text, or -1 if null-terminated
+ * @param status A pointer to an UErrorCode to receive any errors.
+ * @return a struct containing collation element information
+ * @stable ICU 2.0
+ */
+U_STABLE UCollationElements* U_EXPORT2 
+ucol_openElements(const UCollator  *coll,
+                  const UChar      *text,
+                        int32_t    textLength,
+                        UErrorCode *status);
+
+
+/**
+ * get a hash code for a key... Not very useful!
+ * @param key    the given key.
+ * @param length the size of the key array.
+ * @return       the hash code.
+ * @stable ICU 2.0
+ */
+U_STABLE int32_t U_EXPORT2 
+ucol_keyHashCode(const uint8_t* key, int32_t length);
+
+/**
+ * Close a UCollationElements.
+ * Once closed, a UCollationElements may no longer be used.
+ * @param elems The UCollationElements to close.
+ * @stable ICU 2.0
+ */
+U_STABLE void U_EXPORT2 
+ucol_closeElements(UCollationElements *elems);
+
+/**
+ * Reset the collation elements to their initial state.
+ * This will move the 'cursor' to the beginning of the text.
+ * Property settings for collation will be reset to the current status.
+ * @param elems The UCollationElements to reset.
+ * @see ucol_next
+ * @see ucol_previous
+ * @stable ICU 2.0
+ */
+U_STABLE void U_EXPORT2 
+ucol_reset(UCollationElements *elems);
+
+/**
+ * Set the collation elements to use implicit ordering for Han
+ * even if they've been tailored. This will also force Hangul
+ * syllables to be ordered by decomposing them to their component
+ * Jamo.
+ *
+ * @param elems The UCollationElements containing the text.
+ * @param status A pointer to a UErrorCode to reveive any errors.
+ *
+ * @internal
+ */
+U_INTERNAL void U_EXPORT2
+ucol_forceHanImplicit(UCollationElements *elems, UErrorCode *status);
+
+/**
+ * Get the ordering priority of the next collation element in the text.
+ * A single character may contain more than one collation element.
+ * @param elems The UCollationElements containing the text.
+ * @param status A pointer to an UErrorCode to receive any errors.
+ * @return The next collation elements ordering, otherwise returns NULLORDER 
+ *         if an error has occured or if the end of string has been reached
+ * @stable ICU 2.0
+ */
+U_STABLE int32_t U_EXPORT2 
+ucol_next(UCollationElements *elems, UErrorCode *status);
+
+/**
+ * Get the ordering priority of the previous collation element in the text.
+ * A single character may contain more than one collation element.
+ * Note that internally a stack is used to store buffered collation elements. 
+ * It is very rare that the stack will overflow, however if such a case is 
+ * encountered, the problem can be solved by increasing the size 
+ * UCOL_EXPAND_CE_BUFFER_SIZE in ucol_imp.h.
+ * @param elems The UCollationElements containing the text.
+ * @param status A pointer to an UErrorCode to receive any errors. Noteably 
+ *               a U_BUFFER_OVERFLOW_ERROR is returned if the internal stack
+ *               buffer has been exhausted.
+ * @return The previous collation elements ordering, otherwise returns 
+ *         NULLORDER if an error has occured or if the start of string has 
+ *         been reached.
+ * @stable ICU 2.0
+ */
+U_STABLE int32_t U_EXPORT2 
+ucol_previous(UCollationElements *elems, UErrorCode *status);
+
+/**
+ * Get the processed ordering priority of the next collation element in the text.
+ * A single character may contain more than one collation element.
+ *
+ * @param elems The UCollationElements containing the text.
+ * @param ixLow a pointer to an int32_t to receive the iterator index before fetching the CE.
+ * @param ixHigh a pointer to an int32_t to receive the iterator index after fetching the CE.
+ * @param status A pointer to an UErrorCode to receive any errors.
+ * @return The next collation elements ordering, otherwise returns UCOL_PROCESSED_NULLORDER 
+ *         if an error has occured or if the end of string has been reached
+ *
+ * @internal
+ */
+U_INTERNAL int64_t U_EXPORT2
+ucol_nextProcessed(UCollationElements *elems, int32_t *ixLow, int32_t *ixHigh, UErrorCode *status);
+
+/**
+ * Get the processed ordering priority of the previous collation element in the text.
+ * A single character may contain more than one collation element.
+ * Note that internally a stack is used to store buffered collation elements. 
+ * It is very rare that the stack will overflow, however if such a case is 
+ * encountered, the problem can be solved by increasing the size 
+ * UCOL_EXPAND_CE_BUFFER_SIZE in ucol_imp.h.
+ *
+ * @param elems The UCollationElements containing the text.
+ * @param ixLow A pointer to an int32_t to receive the iterator index after fetching the CE
+ * @param ixHigh A pointer to an int32_t to receiver the iterator index before fetching the CE
+ * @param status A pointer to an UErrorCode to receive any errors. Noteably 
+ *               a U_BUFFER_OVERFLOW_ERROR is returned if the internal stack
+ *               buffer has been exhausted.
+ * @return The previous collation elements ordering, otherwise returns 
+ *         UCOL_PROCESSED_NULLORDER if an error has occured or if the start of
+ *         string has been reached.
+ *
+ * @internal
+ */
+U_INTERNAL int64_t U_EXPORT2
+ucol_previousProcessed(UCollationElements *elems, int32_t *ixLow, int32_t *ixHigh, UErrorCode *status);
+
+/**
+ * Get the maximum length of any expansion sequences that end with the 
+ * specified comparison order.
+ * This is useful for .... ?
+ * @param elems The UCollationElements containing the text.
+ * @param order A collation order returned by previous or next.
+ * @return maximum size of the expansion sequences ending with the collation 
+ *         element or 1 if collation element does not occur at the end of any 
+ *         expansion sequence
+ * @stable ICU 2.0
+ */
+U_STABLE int32_t U_EXPORT2 
+ucol_getMaxExpansion(const UCollationElements *elems, int32_t order);
+
+/**
+ * Set the text containing the collation elements.
+ * Property settings for collation will remain the same.
+ * In order to reset the iterator to the current collation property settings,
+ * the API reset() has to be called.
+ * @param elems The UCollationElements to set.
+ * @param text The source text containing the collation elements.
+ * @param textLength The length of text, or -1 if null-terminated.
+ * @param status A pointer to an UErrorCode to receive any errors.
+ * @see ucol_getText
+ * @stable ICU 2.0
+ */
+U_STABLE void U_EXPORT2 
+ucol_setText(      UCollationElements *elems, 
+             const UChar              *text,
+                   int32_t            textLength,
+                   UErrorCode         *status);
+
+/**
+ * Get the offset of the current source character.
+ * This is an offset into the text of the character containing the current
+ * collation elements.
+ * @param elems The UCollationElements to query.
+ * @return The offset of the current source character.
+ * @see ucol_setOffset
+ * @stable ICU 2.0
+ */
+U_STABLE int32_t U_EXPORT2 
+ucol_getOffset(const UCollationElements *elems);
+
+/**
+ * Set the offset of the current source character.
+ * This is an offset into the text of the character to be processed.
+ * Property settings for collation will remain the same.
+ * In order to reset the iterator to the current collation property settings,
+ * the API reset() has to be called.
+ * @param elems The UCollationElements to set.
+ * @param offset The desired character offset.
+ * @param status A pointer to an UErrorCode to receive any errors.
+ * @see ucol_getOffset
+ * @stable ICU 2.0
+ */
+U_STABLE void U_EXPORT2 
+ucol_setOffset(UCollationElements *elems,
+               int32_t        offset,
+               UErrorCode         *status);
+
+/**
+* Get the primary order of a collation order.
+* @param order the collation order
+* @return the primary order of a collation order.
+* @stable ICU 2.6
+*/
+U_STABLE int32_t U_EXPORT2
+ucol_primaryOrder (int32_t order); 
+
+/**
+* Get the secondary order of a collation order.
+* @param order the collation order
+* @return the secondary order of a collation order.
+* @stable ICU 2.6
+*/
+U_STABLE int32_t U_EXPORT2
+ucol_secondaryOrder (int32_t order); 
+
+/**
+* Get the tertiary order of a collation order.
+* @param order the collation order
+* @return the tertiary order of a collation order.
+* @stable ICU 2.6
+*/
+U_STABLE int32_t U_EXPORT2
+ucol_tertiaryOrder (int32_t order); 
+
+#endif /* #if !UCONFIG_NO_COLLATION */
+
+#endif