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