diff options
Diffstat (limited to 'protocols/FacebookRM/JSON_CAJUN/reader.inl')
-rw-r--r-- | protocols/FacebookRM/JSON_CAJUN/reader.inl | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/protocols/FacebookRM/JSON_CAJUN/reader.inl b/protocols/FacebookRM/JSON_CAJUN/reader.inl new file mode 100644 index 0000000000..26339497a0 --- /dev/null +++ b/protocols/FacebookRM/JSON_CAJUN/reader.inl @@ -0,0 +1,524 @@ +/**********************************************
+
+License: BSD
+Project Webpage: http://cajun-jsonapi.sourceforge.net/
+Author: Terry Caton
+
+***********************************************/
+
+#include <cassert>
+#include <set>
+#include <sstream>
+
+/*
+
+TODO:
+* better documentation
+* unicode character decoding
+
+*/
+
+namespace json
+{
+
+
+ inline std::istream& operator >> (std::istream& istr, UnknownElement& elementRoot) {
+ Reader::Read(elementRoot, istr);
+ return istr;
+}
+
+inline Reader::Location::Location() :
+ m_nLine(0),
+ m_nLineOffset(0),
+ m_nDocOffset(0)
+{}
+
+
+//////////////////////
+// Reader::InputStream
+
+class Reader::InputStream // would be cool if we could inherit from std::istream & override "get"
+{
+public:
+ InputStream(std::istream& iStr) :
+ m_iStr(iStr) {}
+
+ // protect access to the input stream, so we can keeep track of document/line offsets
+ char Get(); // big, define outside
+ char Peek() {
+ assert(m_iStr.eof() == false); // enforce reading of only valid stream data
+ return m_iStr.peek();
+ }
+
+ bool EOS() {
+ m_iStr.peek(); // apparently eof flag isn't set until a character read is attempted. whatever.
+ return m_iStr.eof();
+ }
+
+ const Location& GetLocation() const { return m_Location; }
+
+private:
+ std::istream& m_iStr;
+ Location m_Location;
+};
+
+
+inline char Reader::InputStream::Get()
+{
+ assert(m_iStr.eof() == false); // enforce reading of only valid stream data
+ char c = m_iStr.get();
+
+ ++m_Location.m_nDocOffset;
+ if (c == '\n') {
+ ++m_Location.m_nLine;
+ m_Location.m_nLineOffset = 0;
+ }
+ else {
+ ++m_Location.m_nLineOffset;
+ }
+
+ return c;
+}
+
+
+
+//////////////////////
+// Reader::TokenStream
+
+class Reader::TokenStream
+{
+public:
+ TokenStream(const Tokens& tokens);
+
+ const Token& Peek();
+ const Token& Get();
+
+ bool EOS() const;
+
+private:
+ const Tokens& m_Tokens;
+ Tokens::const_iterator m_itCurrent;
+};
+
+
+inline Reader::TokenStream::TokenStream(const Tokens& tokens) :
+ m_Tokens(tokens),
+ m_itCurrent(tokens.begin())
+{}
+
+inline const Reader::Token& Reader::TokenStream::Peek() {
+ assert(m_itCurrent != m_Tokens.end());
+ return *(m_itCurrent);
+}
+
+inline const Reader::Token& Reader::TokenStream::Get() {
+ assert(m_itCurrent != m_Tokens.end());
+ return *(m_itCurrent++);
+}
+
+inline bool Reader::TokenStream::EOS() const {
+ return m_itCurrent == m_Tokens.end();
+}
+
+///////////////////
+// Reader (finally)
+
+
+inline void Reader::Read(Object& object, std::istream& istr) { Read_i(object, istr); }
+inline void Reader::Read(Array& array, std::istream& istr) { Read_i(array, istr); }
+inline void Reader::Read(String& string, std::istream& istr) { Read_i(string, istr); }
+inline void Reader::Read(Number& number, std::istream& istr) { Read_i(number, istr); }
+inline void Reader::Read(Boolean& boolean, std::istream& istr) { Read_i(boolean, istr); }
+inline void Reader::Read(Null& null, std::istream& istr) { Read_i(null, istr); }
+inline void Reader::Read(UnknownElement& unknown, std::istream& istr) { Read_i(unknown, istr); }
+
+
+template <typename ElementTypeT>
+void Reader::Read_i(ElementTypeT& element, std::istream& istr)
+{
+ Reader reader;
+
+ Tokens tokens;
+ InputStream inputStream(istr);
+ reader.Scan(tokens, inputStream);
+
+ TokenStream tokenStream(tokens);
+ reader.Parse(element, tokenStream);
+
+ if (tokenStream.EOS() == false)
+ {
+ const Token& token = tokenStream.Peek();
+ std::string sMessage = "Expected End of token stream; found " + token.sValue;
+ throw ParseException(sMessage, token.locBegin, token.locEnd);
+ }
+}
+
+
+inline void Reader::Scan(Tokens& tokens, InputStream& inputStream)
+{
+ while (EatWhiteSpace(inputStream), // ignore any leading white space...
+ inputStream.EOS() == false) // ...before checking for EOS
+ {
+ // if all goes well, we'll create a token each pass
+ Token token;
+ token.locBegin = inputStream.GetLocation();
+
+ // gives us null-terminated string
+ std::string sChar;
+ sChar.push_back(inputStream.Peek());
+
+ switch (sChar[0])
+ {
+ case '{':
+ token.sValue = sChar[0];
+ MatchExpectedString(sChar, inputStream);
+ token.nType = Token::TOKEN_OBJECT_BEGIN;
+ break;
+
+ case '}':
+ token.sValue = sChar[0];
+ MatchExpectedString(sChar, inputStream);
+ token.nType = Token::TOKEN_OBJECT_END;
+ break;
+
+ case '[':
+ token.sValue = sChar[0];
+ MatchExpectedString(sChar, inputStream);
+ token.nType = Token::TOKEN_ARRAY_BEGIN;
+ break;
+
+ case ']':
+ token.sValue = sChar[0];
+ MatchExpectedString(sChar, inputStream);
+ token.nType = Token::TOKEN_ARRAY_END;
+ break;
+
+ case ',':
+ token.sValue = sChar[0];
+ MatchExpectedString(sChar, inputStream);
+ token.nType = Token::TOKEN_NEXT_ELEMENT;
+ break;
+
+ case ':':
+ token.sValue = sChar[0];
+ MatchExpectedString(sChar, inputStream);
+ token.nType = Token::TOKEN_MEMBER_ASSIGN;
+ break;
+
+ case '"':
+ MatchString(token.sValue, inputStream);
+ token.nType = Token::TOKEN_STRING;
+ break;
+
+ case '-':
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ MatchNumber(token.sValue, inputStream);
+ token.nType = Token::TOKEN_NUMBER;
+ break;
+
+ case 't':
+ token.sValue = "true";
+ MatchExpectedString(token.sValue, inputStream);
+ token.nType = Token::TOKEN_BOOLEAN;
+ break;
+
+ case 'f':
+ token.sValue = "false";
+ MatchExpectedString(token.sValue, inputStream);
+ token.nType = Token::TOKEN_BOOLEAN;
+ break;
+
+ case 'n':
+ token.sValue = "null";
+ MatchExpectedString(token.sValue, inputStream);
+ token.nType = Token::TOKEN_NULL;
+ break;
+
+ default: {
+ std::string sErrorMessage = "Unexpected character in stream: " + sChar;
+ throw ScanException(sErrorMessage, inputStream.GetLocation());
+ }
+ }
+
+ token.locEnd = inputStream.GetLocation();
+ tokens.push_back(token);
+ }
+}
+
+
+inline void Reader::EatWhiteSpace(InputStream& inputStream)
+{
+ while (inputStream.EOS() == false &&
+ ::isspace(inputStream.Peek()))
+ inputStream.Get();
+}
+
+inline void Reader::MatchExpectedString(const std::string& sExpected, InputStream& inputStream)
+{
+ std::string::const_iterator it(sExpected.begin()),
+ itEnd(sExpected.end());
+ for ( ; it != itEnd; ++it) {
+ if (inputStream.EOS() || // did we reach the end before finding what we're looking for...
+ inputStream.Get() != *it) // ...or did we find something different?
+ {
+ std::string sMessage = "Expected string: " + sExpected;
+ throw ScanException(sMessage, inputStream.GetLocation());
+ }
+ }
+
+ // all's well if we made it here, return quietly
+}
+
+
+inline void Reader::MatchString(std::string& string, InputStream& inputStream)
+{
+ MatchExpectedString("\"", inputStream);
+
+ while (inputStream.EOS() == false &&
+ inputStream.Peek() != '"')
+ {
+ char c = inputStream.Get();
+
+ // escape?
+ if (c == '\\' &&
+ inputStream.EOS() == false) // shouldn't have reached the end yet
+ {
+ c = inputStream.Get();
+ switch (c) {
+ case '/': string.push_back('/'); break;
+ case '"': string.push_back('"'); break;
+ case '\\': string.push_back('\\'); break;
+ case 'b': string.push_back('\b'); break;
+ case 'f': string.push_back('\f'); break;
+ case 'n': string.push_back('\n'); break;
+ case 'r': string.push_back('\r'); break;
+ case 't': string.push_back('\t'); break;
+//
+// misacek: Modification due to need
+//
+// case 'u': // TODO: what do we do with this?
+ case 'u': string.append("\\u"); break;
+//
+ default: {
+ std::string sMessage = "Unrecognized escape sequence found in string: \\" + c;
+ throw ScanException(sMessage, inputStream.GetLocation());
+ }
+ }
+ }
+ else {
+ string.push_back(c);
+ }
+ }
+
+ // eat the last '"' that we just peeked
+ MatchExpectedString("\"", inputStream);
+}
+
+
+inline void Reader::MatchNumber(std::string& sNumber, InputStream& inputStream)
+{
+ const char sNumericChars[] = "0123456789.eE-+";
+ std::set<char> numericChars;
+ numericChars.insert(sNumericChars, sNumericChars + sizeof(sNumericChars));
+
+ while (inputStream.EOS() == false &&
+ numericChars.find(inputStream.Peek()) != numericChars.end())
+ {
+ sNumber.push_back(inputStream.Get());
+ }
+}
+
+
+inline void Reader::Parse(UnknownElement& element, Reader::TokenStream& tokenStream)
+{
+ if (tokenStream.EOS()) {
+ std::string sMessage = "Unexpected end of token stream";
+ throw ParseException(sMessage, Location(), Location()); // nowhere to point to
+ }
+
+ const Token& token = tokenStream.Peek();
+ switch (token.nType) {
+ case Token::TOKEN_OBJECT_BEGIN:
+ {
+ // implicit non-const cast will perform conversion for us (if necessary)
+ Object& object = element;
+ Parse(object, tokenStream);
+ break;
+ }
+
+ case Token::TOKEN_ARRAY_BEGIN:
+ {
+ Array& array = element;
+ Parse(array, tokenStream);
+ break;
+ }
+
+ case Token::TOKEN_STRING:
+ {
+ String& string = element;
+ Parse(string, tokenStream);
+ break;
+ }
+
+ case Token::TOKEN_NUMBER:
+ {
+ Number& number = element;
+ Parse(number, tokenStream);
+ break;
+ }
+
+ case Token::TOKEN_BOOLEAN:
+ {
+ Boolean& boolean = element;
+ Parse(boolean, tokenStream);
+ break;
+ }
+
+ case Token::TOKEN_NULL:
+ {
+ Null& null = element;
+ Parse(null, tokenStream);
+ break;
+ }
+
+ default:
+ {
+ std::string sMessage = "Unexpected token: " + token.sValue;
+ throw ParseException(sMessage, token.locBegin, token.locEnd);
+ }
+ }
+}
+
+
+inline void Reader::Parse(Object& object, Reader::TokenStream& tokenStream)
+{
+ MatchExpectedToken(Token::TOKEN_OBJECT_BEGIN, tokenStream);
+
+ bool bContinue = (tokenStream.EOS() == false &&
+ tokenStream.Peek().nType != Token::TOKEN_OBJECT_END);
+ while (bContinue)
+ {
+ Object::Member member;
+
+ // first the member name. save the token in case we have to throw an exception
+ const Token& tokenName = tokenStream.Peek();
+ member.name = MatchExpectedToken(Token::TOKEN_STRING, tokenStream);
+
+ // ...then the key/value separator...
+ MatchExpectedToken(Token::TOKEN_MEMBER_ASSIGN, tokenStream);
+
+ // ...then the value itself (can be anything).
+ Parse(member.element, tokenStream);
+
+ // try adding it to the object (this could throw)
+ try
+ {
+ object.Insert(member);
+ }
+ catch (Exception&)
+ {
+ // must be a duplicate name
+ std::string sMessage = "Duplicate object member token: " + member.name;
+ throw ParseException(sMessage, tokenName.locBegin, tokenName.locEnd);
+ }
+
+ bContinue = (tokenStream.EOS() == false &&
+ tokenStream.Peek().nType == Token::TOKEN_NEXT_ELEMENT);
+ if (bContinue)
+ MatchExpectedToken(Token::TOKEN_NEXT_ELEMENT, tokenStream);
+ }
+
+ MatchExpectedToken(Token::TOKEN_OBJECT_END, tokenStream);
+}
+
+
+inline void Reader::Parse(Array& array, Reader::TokenStream& tokenStream)
+{
+ MatchExpectedToken(Token::TOKEN_ARRAY_BEGIN, tokenStream);
+
+ bool bContinue = (tokenStream.EOS() == false &&
+ tokenStream.Peek().nType != Token::TOKEN_ARRAY_END);
+ while (bContinue)
+ {
+ // ...what's next? could be anything
+ Array::iterator itElement = array.Insert(UnknownElement());
+ UnknownElement& element = *itElement;
+ Parse(element, tokenStream);
+
+ bContinue = (tokenStream.EOS() == false &&
+ tokenStream.Peek().nType == Token::TOKEN_NEXT_ELEMENT);
+ if (bContinue)
+ MatchExpectedToken(Token::TOKEN_NEXT_ELEMENT, tokenStream);
+ }
+
+ MatchExpectedToken(Token::TOKEN_ARRAY_END, tokenStream);
+}
+
+
+inline void Reader::Parse(String& string, Reader::TokenStream& tokenStream)
+{
+ string = MatchExpectedToken(Token::TOKEN_STRING, tokenStream);
+}
+
+
+inline void Reader::Parse(Number& number, Reader::TokenStream& tokenStream)
+{
+ const Token& currentToken = tokenStream.Peek(); // might need this later for throwing exception
+ const std::string& sValue = MatchExpectedToken(Token::TOKEN_NUMBER, tokenStream);
+
+ std::istringstream iStr(sValue);
+ double dValue;
+ iStr >> dValue;
+
+ // did we consume all characters in the token?
+ if (iStr.eof() == false)
+ {
+ std::string sMessage = "Unexpected character in NUMBER token: " + iStr.peek();
+ throw ParseException(sMessage, currentToken.locBegin, currentToken.locEnd);
+ }
+
+ number = dValue;
+}
+
+
+inline void Reader::Parse(Boolean& boolean, Reader::TokenStream& tokenStream)
+{
+ const std::string& sValue = MatchExpectedToken(Token::TOKEN_BOOLEAN, tokenStream);
+ boolean = (sValue == "true" ? true : false);
+}
+
+
+inline void Reader::Parse(Null&, Reader::TokenStream& tokenStream)
+{
+ MatchExpectedToken(Token::TOKEN_NULL, tokenStream);
+}
+
+
+inline const std::string& Reader::MatchExpectedToken(Token::Type nExpected, Reader::TokenStream& tokenStream)
+{
+ if (tokenStream.EOS())
+ {
+ std::string sMessage = "Unexpected End of token stream";
+ throw ParseException(sMessage, Location(), Location()); // nowhere to point to
+ }
+
+ const Token& token = tokenStream.Get();
+ if (token.nType != nExpected)
+ {
+ std::string sMessage = "Unexpected token: " + token.sValue;
+ throw ParseException(sMessage, token.locBegin, token.locEnd);
+ }
+
+ return token.sValue;
+}
+
+} // End namespace
|