Check in the pristine copy of ICU 4.6...

icu46/source/common/usc_impl.h

+/*
+**********************************************************************
+*   Copyright (C) 1999-2002, 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>
+ *
+ * @draft ICU 2.2
+ */
+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.
+ *
+ * @draft ICU 2.2
+ */
+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.
+ *
+ * @draft ICU 2.2
+ */
+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.
+ *
+ * @draft ICU 2.2
+ */
+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.
+ *
+ * @draft ICU 2.2
+ */
+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.
+ *
+ * @draft ICU 2.2
+ */
+U_CAPI UBool U_EXPORT2
+uscript_nextRun(UScriptRun *scriptRun, int32_t *pRunStart, int32_t *pRunLimit, UScriptCode *pRunScript);
+
+#endif