1 // © 2016 and later: Unicode, Inc. and others. 2 // License & terms of use: http://www.unicode.org/copyright.html 3 /* 4 ********************************************************************** 5 * Copyright (c) 2001-2011, International Business Machines 6 * Corporation and others. All Rights Reserved. 7 ********************************************************************** 8 * Date Name Description 9 * 11/19/2001 aliu Creation. 10 ********************************************************************** 11 */ 12 13 #ifndef ICU_UTIL_H 14 #define ICU_UTIL_H 15 16 #include "charstr.h" 17 #include "unicode/unistr.h" 18 #include "unicode/uobject.h" 19 #include "unicode/utypes.h" 20 //-------------------------------------------------------------------- 21 // class ICU_Utility 22 // i18n utility functions, scoped into the class ICU_Utility. 23 //-------------------------------------------------------------------- 24 25 U_NAMESPACE_BEGIN 26 27 class UnicodeMatcher; 28 29 class U_COMMON_API ICU_Utility /* not : public UObject because all methods are static */ { 30 public: 31 32 /** 33 * Append a number to the given UnicodeString in the given radix. 34 * Standard digits '0'-'9' are used and letters 'A'-'Z' for 35 * radices 11 through 36. 36 * @param result the digits of the number are appended here 37 * @param n the number to be converted to digits; may be negative. 38 * If negative, a '-' is prepended to the digits. 39 * @param radix a radix from 2 to 36 inclusive. 40 * @param minDigits the minimum number of digits, not including 41 * any '-', to produce. Values less than 2 have no effect. One 42 * digit is always emitted regardless of this parameter. 43 * @return a reference to result 44 */ 45 static UnicodeString& appendNumber(UnicodeString& result, int32_t n, 46 int32_t radix = 10, 47 int32_t minDigits = 1); 48 49 /** Returns a bogus UnicodeString by value. */ makeBogusString()50 static inline UnicodeString makeBogusString() { 51 UnicodeString result; 52 result.setToBogus(); 53 return result; 54 } 55 56 /** 57 * Return true if the character is NOT printable ASCII. 58 * 59 * This method should really be in UnicodeString (or similar). For 60 * now, we implement it here and share it with friend classes. 61 */ 62 static UBool isUnprintable(UChar32 c); 63 64 /** 65 * Escape unprintable characters using \uxxxx notation for U+0000 to 66 * U+FFFF and \Uxxxxxxxx for U+10000 and above. If the character is 67 * printable ASCII, then do nothing and return false. Otherwise, 68 * append the escaped notation and return true. 69 */ 70 static UBool escapeUnprintable(UnicodeString& result, UChar32 c); 71 72 /** 73 * Returns the index of a character, ignoring quoted text. 74 * For example, in the string "abc'hide'h", the 'h' in "hide" will not be 75 * found by a search for 'h'. 76 * @param text text to be searched 77 * @param start the beginning index, inclusive; <code>0 <= start 78 * <= limit</code>. 79 * @param limit the ending index, exclusive; <code>start <= limit 80 * <= text.length()</code>. 81 * @param c character to search for 82 * @return Offset of the first instance of c, or -1 if not found. 83 */ 84 //?FOR FUTURE USE. DISABLE FOR NOW for coverage reasons. 85 // static int32_t quotedIndexOf(const UnicodeString& text, 86 // int32_t start, int32_t limit, 87 // UChar c); 88 89 /** 90 * Skip over a sequence of zero or more white space characters at pos. 91 * @param advance if true, advance pos to the first non-white-space 92 * character at or after pos, or str.length(), if there is none. 93 * Otherwise leave pos unchanged. 94 * @return the index of the first non-white-space character at or 95 * after pos, or str.length(), if there is none. 96 */ 97 static int32_t skipWhitespace(const UnicodeString& str, int32_t& pos, 98 UBool advance = false); 99 100 /** 101 * Skip over Pattern_White_Space in a Replaceable. 102 * Skipping may be done in the forward or 103 * reverse direction. In either case, the leftmost index will be 104 * inclusive, and the rightmost index will be exclusive. That is, 105 * given a range defined as [start, limit), the call 106 * skipWhitespace(text, start, limit) will advance start past leading 107 * whitespace, whereas the call skipWhitespace(text, limit, start), 108 * will back up limit past trailing whitespace. 109 * @param text the text to be analyzed 110 * @param pos either the start or limit of a range of 'text', to skip 111 * leading or trailing whitespace, respectively 112 * @param stop either the limit or start of a range of 'text', to skip 113 * leading or trailing whitespace, respectively 114 * @return the new start or limit, depending on what was passed in to 115 * 'pos' 116 */ 117 //?FOR FUTURE USE. DISABLE FOR NOW for coverage reasons. 118 //? static int32_t skipWhitespace(const Replaceable& text, 119 //? int32_t pos, int32_t stop); 120 121 /** 122 * Parse a single non-whitespace character 'ch', optionally 123 * preceded by whitespace. 124 * @param id the string to be parsed 125 * @param pos INPUT-OUTPUT parameter. On input, pos[0] is the 126 * offset of the first character to be parsed. On output, pos[0] 127 * is the index after the last parsed character. If the parse 128 * fails, pos[0] will be unchanged. 129 * @param ch the non-whitespace character to be parsed. 130 * @return true if 'ch' is seen preceded by zero or more 131 * whitespace characters. 132 */ 133 static UBool parseChar(const UnicodeString& id, int32_t& pos, UChar ch); 134 135 /** 136 * Parse a pattern string starting at offset pos. Keywords are 137 * matched case-insensitively. Spaces may be skipped and may be 138 * optional or required. Integer values may be parsed, and if 139 * they are, they will be returned in the given array. If 140 * successful, the offset of the next non-space character is 141 * returned. On failure, -1 is returned. 142 * @param pattern must only contain lowercase characters, which 143 * will match their uppercase equivalents as well. A space 144 * character matches one or more required spaces. A '~' character 145 * matches zero or more optional spaces. A '#' character matches 146 * an integer and stores it in parsedInts, which the caller must 147 * ensure has enough capacity. 148 * @param parsedInts array to receive parsed integers. Caller 149 * must ensure that parsedInts.length is >= the number of '#' 150 * signs in 'pattern'. 151 * @return the position after the last character parsed, or -1 if 152 * the parse failed 153 */ 154 static int32_t parsePattern(const UnicodeString& rule, int32_t pos, int32_t limit, 155 const UnicodeString& pattern, int32_t* parsedInts); 156 157 /** 158 * Parse a pattern string within the given Replaceable and a parsing 159 * pattern. Characters are matched literally and case-sensitively 160 * except for the following special characters: 161 * 162 * ~ zero or more Pattern_White_Space chars 163 * 164 * If end of pattern is reached with all matches along the way, 165 * pos is advanced to the first unparsed index and returned. 166 * Otherwise -1 is returned. 167 * @param pat pattern that controls parsing 168 * @param text text to be parsed, starting at index 169 * @param index offset to first character to parse 170 * @param limit offset after last character to parse 171 * @return index after last parsed character, or -1 on parse failure. 172 */ 173 static int32_t parsePattern(const UnicodeString& pat, 174 const Replaceable& text, 175 int32_t index, 176 int32_t limit); 177 178 /** 179 * Parse an integer at pos, either of the form \d+ or of the form 180 * 0x[0-9A-Fa-f]+ or 0[0-7]+, that is, in standard decimal, hex, 181 * or octal format. 182 * @param pos INPUT-OUTPUT parameter. On input, the index of the first 183 * character to parse. On output, the index of the character after the 184 * last parsed character. 185 */ 186 static int32_t parseInteger(const UnicodeString& rule, int32_t& pos, int32_t limit); 187 188 /** 189 * Parse an integer at pos using only ASCII digits. 190 * Base 10 only. 191 * @param pos INPUT-OUTPUT parameter. On input, the index of the first 192 * character to parse. On output, the index of the character after the 193 * last parsed character. 194 */ 195 static int32_t parseAsciiInteger(const UnicodeString& str, int32_t& pos); 196 197 /** 198 * Parse a Unicode identifier from the given string at the given 199 * position. Return the identifier, or an empty string if there 200 * is no identifier. 201 * @param str the string to parse 202 * @param pos INPUT-OUPUT parameter. On INPUT, pos is the 203 * first character to examine. It must be less than str.length(), 204 * and it must not point to a whitespace character. That is, must 205 * have pos < str.length() and 206 * !UCharacter::isWhitespace(str.char32At(pos)). On 207 * OUTPUT, the position after the last parsed character. 208 * @return the Unicode identifier, or an empty string if there is 209 * no valid identifier at pos. 210 */ 211 static UnicodeString parseUnicodeIdentifier(const UnicodeString& str, int32_t& pos); 212 213 /** 214 * Parse an unsigned 31-bit integer at the given offset. Use 215 * UCharacter.digit() to parse individual characters into digits. 216 * @param text the text to be parsed 217 * @param pos INPUT-OUTPUT parameter. On entry, pos is the 218 * offset within text at which to start parsing; it should point 219 * to a valid digit. On exit, pos is the offset after the last 220 * parsed character. If the parse failed, it will be unchanged on 221 * exit. Must be >= 0 on entry. 222 * @param radix the radix in which to parse; must be >= 2 and <= 223 * 36. 224 * @return a non-negative parsed number, or -1 upon parse failure. 225 * Parse fails if there are no digits, that is, if pos does not 226 * point to a valid digit on entry, or if the number to be parsed 227 * does not fit into a 31-bit unsigned integer. 228 */ 229 static int32_t parseNumber(const UnicodeString& text, 230 int32_t& pos, int8_t radix); 231 232 static void appendToRule(UnicodeString& rule, 233 UChar32 c, 234 UBool isLiteral, 235 UBool escapeUnprintable, 236 UnicodeString& quoteBuf); 237 238 static void appendToRule(UnicodeString& rule, 239 const UnicodeString& text, 240 UBool isLiteral, 241 UBool escapeUnprintable, 242 UnicodeString& quoteBuf); 243 244 static void appendToRule(UnicodeString& rule, 245 const UnicodeMatcher* matcher, 246 UBool escapeUnprintable, 247 UnicodeString& quoteBuf); 248 249 private: 250 // do not instantiate 251 ICU_Utility(); 252 }; 253 254 U_NAMESPACE_END 255 256 #endif 257 //eof 258