Merged utf branch changes r178:187 into the trunk

src/regeximpl.h

@@ -0,0 +1,172 @@
+#pragma once
+
+#include "stream.h"
+#include "stringsource.h"
+#include "streamcharsource.h"
+
+namespace YAML
+{
+	// query matches
+	inline bool RegEx::Matches(char ch) const {
+		std::string str;
+		str += ch;
+		return Matches(str);
+	}
+	
+	inline bool RegEx::Matches(const std::string& str) const {
+		return Match(str) >= 0;
+	}
+	
+	inline bool RegEx::Matches(const Stream& in) const {
+		return Match(in) >= 0;
+	}
+
+	template <typename Source>
+	inline bool RegEx::Matches(const Source& source) const {
+		return Match(source) >= 0;
+	}
+
+	// Match
+	// . Matches the given string against this regular expression.
+	// . Returns the number of characters matched.
+	// . Returns -1 if no characters were matched (the reason for
+	//   not returning zero is that we may have an empty regex
+	//   which is ALWAYS successful at matching zero characters).
+	// . REMEMBER that we only match from the start of the buffer!	
+	inline int RegEx::Match(const std::string& str) const
+	{
+		StringCharSource source(str.c_str(), str.size());
+		return Match(source);
+	}
+	
+	inline int RegEx::Match(const Stream& in) const
+	{
+		StreamCharSource source(in);
+		return Match(source);
+	}
+
+	template <typename Source>
+	inline bool RegEx::IsValidSource(const Source& source) const
+	{
+		return source;
+	}
+	
+	template<>
+	inline bool RegEx::IsValidSource<StringCharSource>(const StringCharSource&source) const
+	{
+		return source || m_op == REGEX_EMPTY;
+	}
+
+	template <typename Source>
+	inline int RegEx::Match(const Source& source) const
+	{
+		return IsValidSource(source) ? MatchUnchecked(source) : -1;
+	}
+	
+	template <typename Source>
+	inline int RegEx::MatchUnchecked(const Source& source) const
+	{
+		switch(m_op) {
+			case REGEX_EMPTY:
+				return MatchOpEmpty(source);
+			case REGEX_MATCH:
+				return MatchOpMatch(source);
+			case REGEX_RANGE:
+				return MatchOpRange(source);
+			case REGEX_OR:
+				return MatchOpOr(source);
+			case REGEX_AND:
+				return MatchOpAnd(source);
+			case REGEX_NOT:
+				return MatchOpNot(source);
+			case REGEX_SEQ:
+				return MatchOpSeq(source);
+		}
+		
+		return -1;
+	}
+
+	//////////////////////////////////////////////////////////////////////////////
+	// Operators
+	// Note: the convention MatchOp*<Source> is that we can assume IsSourceValid(source).
+	//       So we do all our checks *before* we call these functions
+	
+	// EmptyOperator
+	template <typename Source>
+	inline int RegEx::MatchOpEmpty(const Source& source) const {
+		return source[0] == Stream::eof() ? 0 : -1;
+	}
+	
+	template <>
+	inline int RegEx::MatchOpEmpty<StringCharSource>(const StringCharSource& source) const {
+		return !source ? 0 : -1;  // the empty regex only is successful on the empty string
+	}
+
+	// MatchOperator
+	template <typename Source>
+	inline int RegEx::MatchOpMatch(const Source& source) const {
+		if(source[0] != m_a)
+			return -1;
+		return 1;
+	}
+	
+	// RangeOperator
+	template <typename Source>
+	inline int RegEx::MatchOpRange(const Source& source) const {
+		if(m_a > source[0] || m_z < source[0])
+			return -1;
+		return 1;
+	}
+	
+	// OrOperator
+	template <typename Source>
+	inline int RegEx::MatchOpOr(const Source& source) const {
+		for(unsigned i=0;i<m_params.size();i++) {
+			int n = m_params[i].MatchUnchecked(source);
+			if(n >= 0)
+				return n;
+		}
+		return -1;
+	}
+	
+	// AndOperator
+	// Note: 'AND' is a little funny, since we may be required to match things
+	//       of different lengths. If we find a match, we return the length of
+	//       the FIRST entry on the list.
+	template <typename Source>
+	inline int RegEx::MatchOpAnd(const Source& source) const {
+		int first = -1;
+		for(unsigned i=0;i<m_params.size();i++) {
+			int n = m_params[i].MatchUnchecked(source);
+			if(n == -1)
+				return -1;
+			if(i == 0)
+				first = n;
+		}
+		return first;
+	}
+	
+	// NotOperator
+	template <typename Source>
+	inline int RegEx::MatchOpNot(const Source& source) const {
+		if(m_params.empty())
+			return -1;
+		if(m_params[0].MatchUnchecked(source) >= 0)
+			return -1;
+		return 1;
+	}
+	
+	// SeqOperator
+	template <typename Source>
+	inline int RegEx::MatchOpSeq(const Source& source) const {
+		int offset = 0;
+		for(unsigned i=0;i<m_params.size();i++) {
+			int n = m_params[i].Match(source + offset); // note Match, not MatchUnchecked because we need to check validity after the offset
+			if(n == -1)
+				return -1;
+			offset += n;
+		}
+		
+		return offset;
+	}
+}