// Copyright (C) 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
**********************************************************************
* Copyright (c) 2001-2011, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
* Date Name Description
* 11/19/2001 aliu Creation.
**********************************************************************
*/
#ifndef ICU_UTIL_H
#define ICU_UTIL_H
#include "unicode/utypes.h"
#include "unicode/uobject.h"
#include "unicode/unistr.h"
//--------------------------------------------------------------------
// class ICU_Utility
// i18n utility functions, scoped into the class ICU_Utility.
//--------------------------------------------------------------------
U_NAMESPACE_BEGIN
class UnicodeMatcher;
class U_COMMON_API ICU_Utility /* not : public UObject because all methods are static */ {
public:
/**
* Append a number to the given UnicodeString in the given radix.
* Standard digits '0'-'9' are used and letters 'A'-'Z' for
* radices 11 through 36.
* @param result the digits of the number are appended here
* @param n the number to be converted to digits; may be negative.
* If negative, a '-' is prepended to the digits.
* @param radix a radix from 2 to 36 inclusive.
* @param minDigits the minimum number of digits, not including
* any '-', to produce. Values less than 2 have no effect. One
* digit is always emitted regardless of this parameter.
* @return a reference to result
*/
static UnicodeString& appendNumber(UnicodeString& result, int32_t n,
int32_t radix = 10,
int32_t minDigits = 1);
/**
* Return true if the character is NOT printable ASCII.
*
* This method should really be in UnicodeString (or similar). For
* now, we implement it here and share it with friend classes.
*/
static UBool isUnprintable(UChar32 c);
/**
* Escape unprintable characters using \uxxxx notation for U+0000 to
* U+FFFF and \Uxxxxxxxx for U+10000 and above. If the character is
* printable ASCII, then do nothing and return FALSE. Otherwise,
* append the escaped notation and return TRUE.
*/
static UBool escapeUnprintable(UnicodeString& result, UChar32 c);
/**
* Returns the index of a character, ignoring quoted text.
* For example, in the string "abc'hide'h", the 'h' in "hide" will not be
* found by a search for 'h'.
* @param text text to be searched
* @param start the beginning index, inclusive; <code>0 <= start
* <= limit</code>.
* @param limit the ending index, exclusive; <code>start <= limit
* <= text.length()</code>.
* @param c character to search for
* @return Offset of the first instance of c, or -1 if not found.
*/
//?FOR FUTURE USE. DISABLE FOR NOW for coverage reasons.
// static int32_t quotedIndexOf(const UnicodeString& text,
// int32_t start, int32_t limit,
// UChar c);
/**
* Skip over a sequence of zero or more white space characters at pos.
* @param advance if true, advance pos to the first non-white-space
* character at or after pos, or str.length(), if there is none.
* Otherwise leave pos unchanged.
* @return the index of the first non-white-space character at or
* after pos, or str.length(), if there is none.
*/
static int32_t skipWhitespace(const UnicodeString& str, int32_t& pos,
UBool advance = FALSE);
/**
* Skip over Pattern_White_Space in a Replaceable.
* Skipping may be done in the forward or
* reverse direction. In either case, the leftmost index will be
* inclusive, and the rightmost index will be exclusive. That is,
* given a range defined as [start, limit), the call
* skipWhitespace(text, start, limit) will advance start past leading
* whitespace, whereas the call skipWhitespace(text, limit, start),
* will back up limit past trailing whitespace.
* @param text the text to be analyzed
* @param pos either the start or limit of a range of 'text', to skip
* leading or trailing whitespace, respectively
* @param stop either the limit or start of a range of 'text', to skip
* leading or trailing whitespace, respectively
* @return the new start or limit, depending on what was passed in to
* 'pos'
*/
//?FOR FUTURE USE. DISABLE FOR NOW for coverage reasons.
//? static int32_t skipWhitespace(const Replaceable& text,
//? int32_t pos, int32_t stop);
/**
* Parse a single non-whitespace character 'ch', optionally
* preceded by whitespace.
* @param id the string to be parsed
* @param pos INPUT-OUTPUT parameter. On input, pos[0] is the
* offset of the first character to be parsed. On output, pos[0]
* is the index after the last parsed character. If the parse
* fails, pos[0] will be unchanged.
* @param ch the non-whitespace character to be parsed.
* @return true if 'ch' is seen preceded by zero or more
* whitespace characters.
*/
static UBool parseChar(const UnicodeString& id, int32_t& pos, UChar ch);
/**
* Parse a pattern string starting at offset pos. Keywords are
* matched case-insensitively. Spaces may be skipped and may be
* optional or required. Integer values may be parsed, and if
* they are, they will be returned in the given array. If
* successful, the offset of the next non-space character is
* returned. On failure, -1 is returned.
* @param pattern must only contain lowercase characters, which
* will match their uppercase equivalents as well. A space
* character matches one or more required spaces. A '~' character
* matches zero or more optional spaces. A '#' character matches
* an integer and stores it in parsedInts, which the caller must
* ensure has enough capacity.
* @param parsedInts array to receive parsed integers. Caller
* must ensure that parsedInts.length is >= the number of '#'
* signs in 'pattern'.
* @return the position after the last character parsed, or -1 if
* the parse failed
*/
static int32_t parsePattern(const UnicodeString& rule, int32_t pos, int32_t limit,
const UnicodeString& pattern, int32_t* parsedInts);
/**
* Parse a pattern string within the given Replaceable and a parsing
* pattern. Characters are matched literally and case-sensitively
* except for the following special characters:
*
* ~ zero or more Pattern_White_Space chars
*
* If end of pattern is reached with all matches along the way,
* pos is advanced to the first unparsed index and returned.
* Otherwise -1 is returned.
* @param pat pattern that controls parsing
* @param text text to be parsed, starting at index
* @param index offset to first character to parse
* @param limit offset after last character to parse
* @return index after last parsed character, or -1 on parse failure.
*/
static int32_t parsePattern(const UnicodeString& pat,
const Replaceable& text,
int32_t index,
int32_t limit);
/**
* Parse an integer at pos, either of the form \d+ or of the form
* 0x[0-9A-Fa-f]+ or 0[0-7]+, that is, in standard decimal, hex,
* or octal format.
* @param pos INPUT-OUTPUT parameter. On input, the first
* character to parse. On output, the character after the last
* parsed character.
*/
static int32_t parseInteger(const UnicodeString& rule, int32_t& pos, int32_t limit);
/**
* Parse a Unicode identifier from the given string at the given
* position. Return the identifier, or an empty string if there
* is no identifier.
* @param str the string to parse
* @param pos INPUT-OUPUT parameter. On INPUT, pos is the
* first character to examine. It must be less than str.length(),
* and it must not point to a whitespace character. That is, must
* have pos < str.length() and
* !UCharacter::isWhitespace(str.char32At(pos)). On
* OUTPUT, the position after the last parsed character.
* @return the Unicode identifier, or an empty string if there is
* no valid identifier at pos.
*/
static UnicodeString parseUnicodeIdentifier(const UnicodeString& str, int32_t& pos);
/**
* Parse an unsigned 31-bit integer at the given offset. Use
* UCharacter.digit() to parse individual characters into digits.
* @param text the text to be parsed
* @param pos INPUT-OUTPUT parameter. On entry, pos is the
* offset within text at which to start parsing; it should point
* to a valid digit. On exit, pos is the offset after the last
* parsed character. If the parse failed, it will be unchanged on
* exit. Must be >= 0 on entry.
* @param radix the radix in which to parse; must be >= 2 and <=
* 36.
* @return a non-negative parsed number, or -1 upon parse failure.
* Parse fails if there are no digits, that is, if pos does not
* point to a valid digit on entry, or if the number to be parsed
* does not fit into a 31-bit unsigned integer.
*/
static int32_t parseNumber(const UnicodeString& text,
int32_t& pos, int8_t radix);
static void appendToRule(UnicodeString& rule,
UChar32 c,
UBool isLiteral,
UBool escapeUnprintable,
UnicodeString& quoteBuf);
static void appendToRule(UnicodeString& rule,
const UnicodeString& text,
UBool isLiteral,
UBool escapeUnprintable,
UnicodeString& quoteBuf);
static void appendToRule(UnicodeString& rule,
const UnicodeMatcher* matcher,
UBool escapeUnprintable,
UnicodeString& quoteBuf);
private:
// do not instantiate
ICU_Utility();
};
U_NAMESPACE_END
#endif
//eof