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+// © 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.
+**********************************************************************
+*/
+
+#include "unicode/unimatch.h"
+#include "unicode/utf16.h"
+#include "patternprops.h"
+#include "util.h"
+
+// Define char16_t constants using hex for EBCDIC compatibility
+
+static const char16_t BACKSLASH = 0x005C; /*\*/
+static const char16_t UPPER_U = 0x0055; /*U*/
+static const char16_t LOWER_U = 0x0075; /*u*/
+static const char16_t APOSTROPHE = 0x0027; // '\''
+static const char16_t SPACE = 0x0020; // ' '
+
+// "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+static const char16_t DIGITS[] = {
+ 48,49,50,51,52,53,54,55,56,57,
+ 65,66,67,68,69,70,71,72,73,74,
+ 75,76,77,78,79,80,81,82,83,84,
+ 85,86,87,88,89,90
+};
+
+U_NAMESPACE_BEGIN
+
+UnicodeString& ICU_Utility::appendNumber(UnicodeString& result, int32_t n,
+ int32_t radix, int32_t minDigits) {
+ if (radix < 2 || radix > 36) {
+ // Bogus radix
+ return result.append((char16_t)63/*?*/);
+ }
+ // Handle negatives
+ if (n < 0) {
+ n = -n;
+ result.append((char16_t)45/*-*/);
+ }
+ // First determine the number of digits
+ int32_t nn = n;
+ int32_t r = 1;
+ while (nn >= radix) {
+ nn /= radix;
+ r *= radix;
+ --minDigits;
+ }
+ // Now generate the digits
+ while (--minDigits > 0) {
+ result.append(DIGITS[0]);
+ }
+ while (r > 0) {
+ int32_t digit = n / r;
+ result.append(DIGITS[digit]);
+ n -= digit * r;
+ r /= radix;
+ }
+ return result;
+}
+
+UBool ICU_Utility::isUnprintable(UChar32 c) {
+ return !(c >= 0x20 && c <= 0x7E);
+}
+
+UBool ICU_Utility::shouldAlwaysBeEscaped(UChar32 c) {
+ if (c < 0x20) {
+ return true; // C0 control codes
+ } else if (c <= 0x7e) {
+ return false; // printable ASCII
+ } else if (c <= 0x9f) {
+ return true; // C1 control codes
+ } else if (c < 0xd800) {
+ return false; // most of the BMP
+ } else if (c <= 0xdfff || (0xfdd0 <= c && c <= 0xfdef) || (c & 0xfffe) == 0xfffe) {
+ return true; // surrogate or noncharacter code points
+ } else if (c <= 0x10ffff) {
+ return false; // all else
+ } else {
+ return true; // not a code point
+ }
+}
+
+UBool ICU_Utility::escapeUnprintable(UnicodeString& result, UChar32 c) {
+ if (isUnprintable(c)) {
+ escape(result, c);
+ return true;
+ }
+ return false;
+}
+
+UnicodeString &ICU_Utility::escape(UnicodeString& result, UChar32 c) {
+ result.append(BACKSLASH);
+ if (c & ~0xFFFF) {
+ result.append(UPPER_U);
+ result.append(DIGITS[0xF&(c>>28)]);
+ result.append(DIGITS[0xF&(c>>24)]);
+ result.append(DIGITS[0xF&(c>>20)]);
+ result.append(DIGITS[0xF&(c>>16)]);
+ } else {
+ result.append(LOWER_U);
+ }
+ result.append(DIGITS[0xF&(c>>12)]);
+ result.append(DIGITS[0xF&(c>>8)]);
+ result.append(DIGITS[0xF&(c>>4)]);
+ result.append(DIGITS[0xF&c]);
+ return result;
+}
+
+/**
+ * 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'.
+ */
+// FOR FUTURE USE. DISABLE FOR NOW for coverage reasons.
+/*
+int32_t ICU_Utility::quotedIndexOf(const UnicodeString& text,
+ int32_t start, int32_t limit,
+ char16_t charToFind) {
+ for (int32_t i=start; i<limit; ++i) {
+ char16_t c = text.charAt(i);
+ if (c == BACKSLASH) {
+ ++i;
+ } else if (c == APOSTROPHE) {
+ while (++i < limit
+ && text.charAt(i) != APOSTROPHE) {}
+ } else if (c == charToFind) {
+ return i;
+ }
+ }
+ return -1;
+}
+*/
+
+/**
+ * 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.
+ */
+int32_t ICU_Utility::skipWhitespace(const UnicodeString& str, int32_t& pos,
+ UBool advance) {
+ int32_t p = pos;
+ const char16_t* s = str.getBuffer();
+ p = (int32_t)(PatternProps::skipWhiteSpace(s + p, str.length() - p) - s);
+ if (advance) {
+ pos = p;
+ }
+ return p;
+}
+
+/**
+ * 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.
+//?int32_t ICU_Utility::skipWhitespace(const Replaceable& text,
+//? int32_t pos, int32_t stop) {
+//? UChar32 c;
+//? UBool isForward = (stop >= pos);
+//?
+//? if (!isForward) {
+//? --pos; // pos is a limit, so back up by one
+//? }
+//?
+//? while (pos != stop &&
+//? PatternProps::isWhiteSpace(c = text.char32At(pos))) {
+//? if (isForward) {
+//? pos += U16_LENGTH(c);
+//? } else {
+//? pos -= U16_LENGTH(c);
+//? }
+//? }
+//?
+//? if (!isForward) {
+//? ++pos; // make pos back into a limit
+//? }
+//?
+//? return pos;
+//?}
+
+/**
+ * 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.
+ */
+UBool ICU_Utility::parseChar(const UnicodeString& id, int32_t& pos, char16_t ch) {
+ int32_t start = pos;
+ skipWhitespace(id, pos, true);
+ if (pos == id.length() ||
+ id.charAt(pos) != ch) {
+ pos = start;
+ return false;
+ }
+ ++pos;
+ return true;
+}
+
+/**
+ * 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.
+ */
+int32_t ICU_Utility::parsePattern(const UnicodeString& pat,
+ const Replaceable& text,
+ int32_t index,
+ int32_t limit) {
+ int32_t ipat = 0;
+
+ // empty pattern matches immediately
+ if (ipat == pat.length()) {
+ return index;
+ }
+
+ UChar32 cpat = pat.char32At(ipat);
+
+ while (index < limit) {
+ UChar32 c = text.char32At(index);
+
+ // parse \s*
+ if (cpat == 126 /*~*/) {
+ if (PatternProps::isWhiteSpace(c)) {
+ index += U16_LENGTH(c);
+ continue;
+ } else {
+ if (++ipat == pat.length()) {
+ return index; // success; c unparsed
+ }
+ // fall thru; process c again with next cpat
+ }
+ }
+
+ // parse literal
+ else if (c == cpat) {
+ index += U16_LENGTH(c);
+ ipat += U16_LENGTH(cpat);
+ if (ipat == pat.length()) {
+ return index; // success; c parsed
+ }
+ // fall thru; get next cpat
+ }
+
+ // match failure of literal
+ else {
+ return -1;
+ }
+
+ cpat = pat.char32At(ipat);
+ }
+
+ return -1; // text ended before end of pat
+}
+
+int32_t ICU_Utility::parseAsciiInteger(const UnicodeString& str, int32_t& pos) {
+ int32_t result = 0;
+ char16_t c;
+ while (pos < str.length() && (c = str.charAt(pos)) >= u'0' && c <= u'9') {
+ result = result * 10 + (c - u'0');
+ pos++;
+ }
+ return result;
+}
+
+/**
+ * Append a character to a rule that is being built up. To flush
+ * the quoteBuf to rule, make one final call with isLiteral == true.
+ * If there is no final character, pass in (UChar32)-1 as c.
+ * @param rule the string to append the character to
+ * @param c the character to append, or (UChar32)-1 if none.
+ * @param isLiteral if true, then the given character should not be
+ * quoted or escaped. Usually this means it is a syntactic element
+ * such as > or $
+ * @param escapeUnprintable if true, then unprintable characters
+ * should be escaped using \uxxxx or \Uxxxxxxxx. These escapes will
+ * appear outside of quotes.
+ * @param quoteBuf a buffer which is used to build up quoted
+ * substrings. The caller should initially supply an empty buffer,
+ * and thereafter should not modify the buffer. The buffer should be
+ * cleared out by, at the end, calling this method with a literal
+ * character.
+ */
+void ICU_Utility::appendToRule(UnicodeString& rule,
+ UChar32 c,
+ UBool isLiteral,
+ UBool escapeUnprintable,
+ UnicodeString& quoteBuf) {
+ // If we are escaping unprintables, then escape them outside
+ // quotes. \u and \U are not recognized within quotes. The same
+ // logic applies to literals, but literals are never escaped.
+ if (isLiteral ||
+ (escapeUnprintable && ICU_Utility::isUnprintable(c))) {
+ if (quoteBuf.length() > 0) {
+ // We prefer backslash APOSTROPHE to double APOSTROPHE
+ // (more readable, less similar to ") so if there are
+ // double APOSTROPHEs at the ends, we pull them outside
+ // of the quote.
+
+ // If the first thing in the quoteBuf is APOSTROPHE
+ // (doubled) then pull it out.
+ while (quoteBuf.length() >= 2 &&
+ quoteBuf.charAt(0) == APOSTROPHE &&
+ quoteBuf.charAt(1) == APOSTROPHE) {
+ rule.append(BACKSLASH).append(APOSTROPHE);
+ quoteBuf.remove(0, 2);
+ }
+ // If the last thing in the quoteBuf is APOSTROPHE
+ // (doubled) then remove and count it and add it after.
+ int32_t trailingCount = 0;
+ while (quoteBuf.length() >= 2 &&
+ quoteBuf.charAt(quoteBuf.length()-2) == APOSTROPHE &&
+ quoteBuf.charAt(quoteBuf.length()-1) == APOSTROPHE) {
+ quoteBuf.truncate(quoteBuf.length()-2);
+ ++trailingCount;
+ }
+ if (quoteBuf.length() > 0) {
+ rule.append(APOSTROPHE);
+ rule.append(quoteBuf);
+ rule.append(APOSTROPHE);
+ quoteBuf.truncate(0);
+ }
+ while (trailingCount-- > 0) {
+ rule.append(BACKSLASH).append(APOSTROPHE);
+ }
+ }
+ if (c != (UChar32)-1) {
+ /* Since spaces are ignored during parsing, they are
+ * emitted only for readability. We emit one here
+ * only if there isn't already one at the end of the
+ * rule.
+ */
+ if (c == SPACE) {
+ int32_t len = rule.length();
+ if (len > 0 && rule.charAt(len-1) != c) {
+ rule.append(c);
+ }
+ } else if (!escapeUnprintable || !ICU_Utility::escapeUnprintable(rule, c)) {
+ rule.append(c);
+ }
+ }
+ }
+
+ // Escape ' and '\' and don't begin a quote just for them
+ else if (quoteBuf.length() == 0 &&
+ (c == APOSTROPHE || c == BACKSLASH)) {
+ rule.append(BACKSLASH);
+ rule.append(c);
+ }
+
+ // Specials (printable ascii that isn't [0-9a-zA-Z]) and
+ // whitespace need quoting. Also append stuff to quotes if we are
+ // building up a quoted substring already.
+ else if (quoteBuf.length() > 0 ||
+ (c >= 0x0021 && c <= 0x007E &&
+ !((c >= 0x0030/*'0'*/ && c <= 0x0039/*'9'*/) ||
+ (c >= 0x0041/*'A'*/ && c <= 0x005A/*'Z'*/) ||
+ (c >= 0x0061/*'a'*/ && c <= 0x007A/*'z'*/))) ||
+ PatternProps::isWhiteSpace(c)) {
+ quoteBuf.append(c);
+ // Double ' within a quote
+ if (c == APOSTROPHE) {
+ quoteBuf.append(c);
+ }
+ }
+
+ // Otherwise just append
+ else {
+ rule.append(c);
+ }
+}
+
+void ICU_Utility::appendToRule(UnicodeString& rule,
+ const UnicodeString& text,
+ UBool isLiteral,
+ UBool escapeUnprintable,
+ UnicodeString& quoteBuf) {
+ for (int32_t i=0; i<text.length(); ++i) {
+ appendToRule(rule, text[i], isLiteral, escapeUnprintable, quoteBuf);
+ }
+}
+
+/**
+ * Given a matcher reference, which may be null, append its
+ * pattern as a literal to the given rule.
+ */
+void ICU_Utility::appendToRule(UnicodeString& rule,
+ const UnicodeMatcher* matcher,
+ UBool escapeUnprintable,
+ UnicodeString& quoteBuf) {
+ if (matcher != nullptr) {
+ UnicodeString pat;
+ appendToRule(rule, matcher->toPattern(pat, escapeUnprintable),
+ true, escapeUnprintable, quoteBuf);
+ }
+}
+
+U_NAMESPACE_END
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