File indexing completed on 2024-04-21 03:41:37

 /*
     SPDX-FileCopyrightText: 2005 Inge Wallin <inge@lysator.liu.se>
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "parser.h"
 
 #include <cctype>
 
 #include "kalzium_libscience_debug.h"
 
 Parser::Parser()
 {
     start(QString());
 }
 
 Parser::Parser(const QString &_str)
 {
     start(_str);
 }
 
 Parser::~Parser() = default;
 
 void Parser::start(const QString &_str)
 {
     m_str = _str;
 
     if (_str.isNull()) {
         m_index = -1;
         m_nextChar = -1;
         m_nextToken = -1;
     } else {
         m_index = 0;
         m_nextChar = m_str.at(0).toLatin1();
         getNextToken();
     }
 }
 
 // ----------------------------------------------------------------
 
 // Skip whitespace, and try to parse the following characters as an int.
 //
 // Return true if successful.
 
 bool Parser::parseInt(int *_result)
 {
     int sign = 1;
 
     skipWhitespace();
 
     if (m_nextChar == '-') {
         sign = -1;
         getNextChar();
     }
 
     if (!isdigit(m_nextChar)) {
         return false;
     }
 
     int result = 0;
     while (isdigit(m_nextChar)) {
         result = result * 10 + (m_nextChar - '0');
         getNextChar();
     }
 
     *_result = sign * result;
     return true;
 }
 
 // Skip whitespace, and try to parse the following characters as a
 // simple float of the type -?[0-9]+'.'?[0-9]*
 //
 // Return true if successful.
 
 bool Parser::parseSimpleFloat(double *_result)
 {
     double sign = 1.0;
 
     skipWhitespace();
     if (m_nextChar == '-') {
         sign = -1.0;
         getNextChar();
     }
 
     if (!isdigit(m_nextChar)) {
         return false;
     }
 
     double result = 0.0;
 
     // The integer.
     while (isdigit(m_nextChar)) {
         result = result * 10.0 + (double)(m_nextChar - '0');
         getNextChar();
     }
     *_result = result;
 
     if (m_nextChar != '.' || !isdigit(getNextChar())) {
         *_result = sign * result;
         return true;
     }
 
     double decimal = 0.1;
     while (isdigit(m_nextChar)) {
         result += decimal * (double)(m_nextChar - '0');
         decimal /= 10.0;
         getNextChar();
     }
 
     *_result = sign * result;
     return true;
 }
 
 // ----------------------------------------------------------------
 //                           protected methods
 
 int Parser::getNextChar()
 {
     //    qCDebug(KALZIUM_LIBSCIENCE_LOG) << "Parser::getNextChar(): char = " << m_nextChar;
     //    qCDebug(KALZIUM_LIBSCIENCE_LOG) << "m_str.size() " << m_str.size()  << " with m_str: " << m_str  << " and m_index: " << m_index;
 
     ++m_index;
 
     if (m_index == -1) {
         return -1;
     }
 
     // If end of string, then reset the parser.
     if (m_index == m_str.size()) {
         m_index = -1;
         m_nextChar = -1;
     } else {
         m_nextChar = m_str.at(m_index).toLatin1();
     }
 
     // Take care of null-terminated strings.
     if (m_nextChar == 0) {
         m_index = -1;
         m_nextChar = -1;
     }
 
     return m_nextChar;
 }
 
 int Parser::skipWhitespace()
 {
     while (QChar(m_nextChar).isSpace()) {
         getNextChar();
     }
 
     return m_nextChar;
 }
 
 // Get the next token.  This corresponds to the lexical analyzer of a
 // standard parser, e.g as generated by lex.
 //
 // This basic parser supports integers and simple
 // floats.  Reimplement this method to extend it.
 
 int Parser::getNextToken()
 {
     int saveIndex = m_index;
 
     skipWhitespace();
     if (isdigit(nextChar())) {
         // At this point we know that there is a valid number in the
         // string.  The only question now, is whether it is an int or a
         // float.
 
         parseInt(&m_intVal);
 
         skipWhitespace();
         if (nextChar() == '.') {
             m_index = saveIndex;
 
             // No need to check since we already know it is correct.
             (void)parseSimpleFloat(&m_floatVal);
             m_nextToken = FLOAT_TOKEN;
         } else {
             m_nextToken = INT_TOKEN;
         }
     } else if (nextChar() != -1) {
         // Any character.
         m_nextToken = nextChar();
         getNextChar();
     } else {
         // End of string.
         m_nextToken = -1;
     }
 
     return m_nextToken;
 }