usc_impl.h (5560B)
1 // © 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ********************************************************************** 5 * Copyright (C) 1999-2011, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ********************************************************************** 8 * 9 * File USC_IMPL.H 10 * 11 * Modification History: 12 * 13 * Date Name Description 14 * 07/08/2002 Eric Mader Creation. 15 ****************************************************************************** 16 */ 17 18 #ifndef USC_IMPL_H 19 #define USC_IMPL_H 20 #include "unicode/utypes.h" 21 #include "unicode/uscript.h" 22 23 /** 24 * <code>UScriptRun</code> is used to find runs of characters in 25 * the same script. It implements a simple iterator over an array 26 * of characters. The iterator will resolve script-neutral characters 27 * like punctuation into the script of the surrounding characters. 28 * 29 * The iterator will try to match paired punctuation. If it sees an 30 * opening punctuation character, it will remember the script that 31 * was assigned to that character, and assign the same script to the 32 * matching closing punctuation. 33 * 34 * Scripts are chosen based on the <code>UScriptCode</code> enumeration. 35 * No attempt is made to combine related scripts into a single run. In 36 * particular, Hiragana, Katakana, and Han characters will appear in separate 37 * runs. 38 39 * Here is an example of how to iterate over script runs: 40 * <pre> 41 * \code 42 * void printScriptRuns(const UChar *text, int32_t length) 43 * { 44 * UErrorCode error = U_ZERO_ERROR; 45 * UScriptRun *scriptRun = uscript_openRun(text, testLength, &error); 46 * int32_t start = 0, limit = 0; 47 * UScriptCode code = USCRIPT_INVALID_CODE; 48 * 49 * while (uscript_nextRun(&start, &limit, &code)) { 50 * printf("Script '%s' from %d to %d.\n", uscript_getName(code), start, limit); 51 * } 52 * 53 * uscript_closeRun(scriptRun); 54 * } 55 * </pre> 56 */ 57 struct UScriptRun; 58 59 typedef struct UScriptRun UScriptRun; 60 61 /** 62 * Create a <code>UScriptRun</code> object for iterating over the given text. This object must 63 * be freed using <code>uscript_closeRun()</code>. Note that this object does not copy the source text, 64 * only the pointer to it. You must make sure that the pointer remains valid until you call 65 * <code>uscript_closeRun()</code> or <code>uscript_setRunText()</code>. 66 * 67 * @param src is the address of the array of characters over which to iterate. 68 * if <code>src == NULL</code> and <code>length == 0</code>, 69 * an empty <code>UScriptRun</code> object will be returned. 70 * 71 * @param length is the number of characters over which to iterate. 72 * 73 * @param pErrorCode is a pointer to a valid <code>UErrorCode</code> value. If this value 74 * indicates a failure on entry, the function will immediately return. 75 * On exit the value will indicate the success of the operation. 76 * 77 * @return the address of <code>UScriptRun</code> object which will iterate over the text, 78 * or <code>NULL</code> if the operation failed. 79 */ 80 U_CAPI UScriptRun * U_EXPORT2 81 uscript_openRun(const UChar *src, int32_t length, UErrorCode *pErrorCode); 82 83 /** 84 * Frees the given <code>UScriptRun</code> object and any storage associated with it. 85 * On return, scriptRun no longer points to a valid <code>UScriptRun</code> object. 86 * 87 * @param scriptRun is the <code>UScriptRun</code> object which will be freed. 88 */ 89 U_CAPI void U_EXPORT2 90 uscript_closeRun(UScriptRun *scriptRun); 91 92 /** 93 * Reset the <code>UScriptRun</code> object so that it will start iterating from 94 * the beginning. 95 * 96 * @param scriptRun is the address of the <code>UScriptRun</code> object to be reset. 97 */ 98 U_CAPI void U_EXPORT2 99 uscript_resetRun(UScriptRun *scriptRun); 100 101 /** 102 * Change the text over which the given <code>UScriptRun</code> object iterates. 103 * 104 * @param scriptRun is the <code>UScriptRun</code> object which will be changed. 105 * 106 * @param src is the address of the new array of characters over which to iterate. 107 * If <code>src == NULL</code> and <code>length == 0</code>, 108 * the <code>UScriptRun</code> object will become empty. 109 * 110 * @param length is the new number of characters over which to iterate 111 * 112 * @param pErrorCode is a pointer to a valid <code>UErrorCode</code> value. If this value 113 * indicates a failure on entry, the function will immediately return. 114 * On exit the value will indicate the success of the operation. 115 */ 116 U_CAPI void U_EXPORT2 117 uscript_setRunText(UScriptRun *scriptRun, const UChar *src, int32_t length, UErrorCode *pErrorCode); 118 119 /** 120 * Advance the <code>UScriptRun</code> object to the next script run, return the start and limit 121 * offsets, and the script of the run. 122 * 123 * @param scriptRun is the address of the <code>UScriptRun</code> object. 124 * 125 * @param pRunStart is a pointer to the variable to receive the starting offset of the next run. 126 * This pointer can be <code>NULL</code> if the value is not needed. 127 * 128 * @param pRunLimit is a pointer to the variable to receive the limit offset of the next run. 129 * This pointer can be <code>NULL</code> if the value is not needed. 130 * 131 * @param pRunScript is a pointer to the variable to receive the UScriptCode for the 132 * script of the current run. This pointer can be <code>NULL</code> if the value is not needed. 133 * 134 * @return true if there was another script run. 135 */ 136 U_CAPI UBool U_EXPORT2 137 uscript_nextRun(UScriptRun *scriptRun, int32_t *pRunStart, int32_t *pRunLimit, UScriptCode *pRunScript); 138 139 #endif