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/*
**********************************************************************
* Copyright (C) 1999-2011, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
*
* File USC_IMPL.H
*
* Modification History:
*
* Date Name Description
* 07/08/2002 Eric Mader Creation.
******************************************************************************
*/
#ifndef USC_IMPL_H
#define USC_IMPL_H
#include "unicode/utypes.h"
#include "unicode/uscript.h"
/**
* <code>UScriptRun</code> is used to find runs of characters in
* the same script. It implements a simple iterator over an array
* of characters. The iterator will resolve script-neutral characters
* like punctuation into the script of the surrounding characters.
*
* The iterator will try to match paired punctuation. If it sees an
* opening punctuation character, it will remember the script that
* was assigned to that character, and assign the same script to the
* matching closing punctuation.
*
* Scripts are chosen based on the <code>UScriptCode</code> enumeration.
* No attempt is made to combine related scripts into a single run. In
* particular, Hiragana, Katakana, and Han characters will appear in seperate
* runs.
* Here is an example of how to iterate over script runs:
* <pre>
* \code
* void printScriptRuns(const UChar *text, int32_t length)
* {
* UErrorCode error = U_ZERO_ERROR;
* UScriptRun *scriptRun = uscript_openRun(text, testLength, &error);
* int32_t start = 0, limit = 0;
* UScriptCode code = USCRIPT_INVALID_CODE;
*
* while (uscript_nextRun(&start, &limit, &code)) {
* printf("Script '%s' from %d to %d.\n", uscript_getName(code), start, limit);
* }
*
* uscript_closeRun(scriptRun);
* }
* </pre>
*/
struct UScriptRun;
typedef struct UScriptRun UScriptRun;
/**
* Create a <code>UScriptRun</code> object for iterating over the given text. This object must
* be freed using <code>uscript_closeRun()</code>. Note that this object does not copy the source text,
* only the pointer to it. You must make sure that the pointer remains valid until you call
* <code>uscript_closeRun()</code> or <code>uscript_setRunText()</code>.
*
* @param src is the address of the array of characters over which to iterate.
* if <code>src == NULL</code> and <code>length == 0</code>,
* an empty <code>UScriptRun</code> object will be returned.
*
* @param length is the number of characters over which to iterate.
*
* @param pErrorCode is a pointer to a valid <code>UErrorCode</code> value. If this value
* indicates a failure on entry, the function will immediately return.
* On exit the value will indicate the success of the operation.
*
* @return the address of <code>UScriptRun</code> object which will iterate over the text,
* or <code>NULL</code> if the operation failed.
*/
U_CAPI UScriptRun * U_EXPORT2
uscript_openRun(const UChar *src, int32_t length, UErrorCode *pErrorCode);
/**
* Frees the given <code>UScriptRun</code> object and any storage associated with it.
* On return, scriptRun no longer points to a valid <code>UScriptRun</code> object.
*
* @param scriptRun is the <code>UScriptRun</code> object which will be freed.
*/
U_CAPI void U_EXPORT2
uscript_closeRun(UScriptRun *scriptRun);
/**
* Reset the <code>UScriptRun</code> object so that it will start iterating from
* the beginning.
*
* @param scriptRun is the address of the <code>UScriptRun</code> object to be reset.
*/
U_CAPI void U_EXPORT2
uscript_resetRun(UScriptRun *scriptRun);
/**
* Change the text over which the given <code>UScriptRun</code> object iterates.
*
* @param scriptRun is the <code>UScriptRun</code> object which will be changed.
*
* @param src is the address of the new array of characters over which to iterate.
* If <code>src == NULL</code> and <code>length == 0</code>,
* the <code>UScriptRun</code> object will become empty.
*
* @param length is the new number of characters over which to iterate
*
* @param pErrorCode is a pointer to a valid <code>UErrorCode</code> value. If this value
* indicates a failure on entry, the function will immediately return.
* On exit the value will indicate the success of the operation.
*/
U_CAPI void U_EXPORT2
uscript_setRunText(UScriptRun *scriptRun, const UChar *src, int32_t length, UErrorCode *pErrorCode);
/**
* Advance the <code>UScriptRun</code> object to the next script run, return the start and limit
* offsets, and the script of the run.
*
* @param scriptRun is the address of the <code>UScriptRun</code> object.
*
* @param pRunStart is a pointer to the variable to receive the starting offset of the next run.
* This pointer can be <code>NULL</code> if the value is not needed.
*
* @param pRunLimit is a pointer to the variable to receive the limit offset of the next run.
* This pointer can be <code>NULL</code> if the value is not needed.
*
* @param pRunScript is a pointer to the variable to receive the UScriptCode for the
* script of the current run. This pointer can be <code>NULL</code> if the value is not needed.
*
* @return true if there was another script run.
*/
U_CAPI UBool U_EXPORT2
uscript_nextRun(UScriptRun *scriptRun, int32_t *pRunStart, int32_t *pRunLimit, UScriptCode *pRunScript);
#endif