+void GenericRequest::setLangDefaults(bool langFromClient, const XMLCh* defaultRange)
+{
+ m_langFromClient = langFromClient;
+ m_defaultRange.clear();
+ if (!defaultRange)
+ return;
+ float q = 0.0f;
+ XMLStringTokenizer tokens(defaultRange);
+ while (tokens.hasMoreTokens()) {
+ const XMLCh* t = tokens.nextToken();
+ if (t && *t) {
+ vector<xstring> tagArray;
+ static const XMLCh delims[] = {chDash, chNull};
+ XMLStringTokenizer tags(t, delims);
+ while (tags.hasMoreTokens())
+ tagArray.push_back(tags.nextToken());
+ m_defaultRange.insert(langrange_t::value_type(q, tagArray));
+ q -= 0.0001f;
+ }
+ }
+}
+
+bool GenericRequest::startLangMatching() const
+{
+ // This is a no-op except on the first call, to populate the
+ // range information to use in matching.
+ if (m_langRange.empty()) {
+ if (m_langFromClient) {
+ string hdr(getLanguageRange());
+ char_separator<char> sep1(", "); // tags are split by commas or spaces
+ char_separator<char> sep2("; "); // quality is separated by semicolon
+ tokenizer< char_separator<char> > tokens(hdr, sep1);
+ for (tokenizer< char_separator<char> >::iterator t = tokens.begin(); t != tokens.end(); ++t) {
+ string tag = trim_copy(*t); // handle any surrounding ws
+ tokenizer< char_separator<char> > subtokens(tag, sep2);
+ tokenizer< char_separator<char> >::iterator s = subtokens.begin();
+ if (s != subtokens.end() && *s != "*") {
+ float q = 1.0f;
+ auto_ptr_XMLCh lang((s++)->c_str());
+
+ // Check for quality tag
+ if (s != subtokens.end() && starts_with(*s, "q=")) {
+ try {
+ q = lexical_cast<float,string>(s->c_str() + 2);
+ }
+ catch (bad_lexical_cast&) {
+ q = 0.0f;
+ }
+ }
+
+ // Split range into tokens.
+ vector<xstring> tagArray;
+ static const XMLCh delims[] = {chDash, chNull};
+ XMLStringTokenizer tags(lang.get(), delims);
+ const XMLCh* tag;
+ while (tags.hasMoreTokens()) {
+ tag = tags.nextToken();
+ if (*tag != chAsterisk)
+ tagArray.push_back(tag);
+ }
+
+ if (tagArray.empty())
+ continue;
+
+ // Adjust q using the server priority list. As long as the supplied q deltas are larger than
+ // factors like .0001, the client settings will always trump ours.
+ if (!m_defaultRange.empty()) {
+ float adj = (m_defaultRange.size() + 1) * 0.0001f;
+ for (langrange_t::const_iterator prio = m_defaultRange.begin(); prio != m_defaultRange.end(); ++prio) {
+ if (prio->second == tagArray) {
+ adj = prio->first;
+ break;
+ }
+ }
+ q -= adj;
+ }
+ m_langRange.insert(langrange_t::value_type(q, tagArray));
+ }
+ }
+ }
+ else {
+ m_langRange = m_defaultRange;
+ }
+ }
+
+ m_langRangeIter = m_langRange.crbegin();
+ return (m_langRangeIter != m_langRange.crend());
+}
+
+bool GenericRequest::continueLangMatching() const
+{
+ return (++m_langRangeIter != m_langRange.crend());
+}
+
+bool GenericRequest::matchLang(const XMLCh* tag) const
+{
+ if (m_langRangeIter == m_langRange.crend())
+ return false;
+
+ // To match against a given range, the range has to be built up and then
+ // truncated segment by segment to look for a match against the tag.
+ // That allows more specific ranges like en-US to match the tag en.
+ // The "end" fence tells us how much of the original range to recompose
+ // into a hyphenated string, and we stop on a match, or when the fence
+ // moves back to the beginning of the array.
+ bool match = false;
+ vector<xstring>::size_type end = m_langRangeIter->second.size();
+ do {
+ // Skip single-character private extension separators.
+ while (end > 1 && m_langRangeIter->second[end-1].length() <= 1)
+ --end;
+ // Build a range from 0 to end - 1 of segments.
+ xstring compareTo(m_langRangeIter->second[0]);
+ for (vector<xstring>::size_type ix = 1; ix <= end - 1; ++ix)
+ compareTo = compareTo + chDash + m_langRangeIter->second[ix];
+ match = (compareTo.length() > 1 && XMLString::compareIStringASCII(compareTo.c_str(), tag) == 0);
+ } while (!match && --end > 0);
+ return match;
+}
+