runtime/kdesu/kdesud/lexer.cpp

   1 /* vi: ts=8 sts=4 sw=4
   2  *
   3  * This file is part of the KDE project, module kdesu.
   4  * Copyright (C) 1999,2000 Geert Jansen <jansen@kde.org>
   5  *
   6  * lexer.cpp: A lexer for the kdesud protocol. See kdesud.cpp for a
   7  *            description of the protocol.
   8  */
   9
  10 #include "lexer.h"
  11
  12 #include <ctype.h>
  13
  14
  15 Lexer::Lexer(const QByteArray &input)
  16 {
  17     m_Input = input;
  18     in = 0;
  19 }
  20
  21 Lexer::~Lexer()
  22 {
  23     // Erase buffers
  24     m_Input.fill('x');
  25     m_Output.fill('x');
  26 }
  27
  28 QByteArray &Lexer::lval()
  29 {
  30     return m_Output;
  31 }
  32
  33 /*
  34  * lex() is the lexer. There is no end-of-input check here so that has to be
  35  * done by the caller.
  36  */
  37
  38 int Lexer::lex()
  39 {
  40     char c;
  41
  42     c = m_Input[in++];
  43     m_Output.fill('x');
  44     m_Output.resize(0);
  45
  46     while (1)
  47     {
  48         // newline?
  49         if (c == '\n')
  50             return '\n';
  51
  52         // No control characters
  53         if (iscntrl(c))
  54             return Tok_none;
  55
  56         if (isspace(c))
  57             while (isspace(c = m_Input[in++]))
  58                 ;
  59
  60         // number?
  61         if (isdigit(c))
  62         {
  63             m_Output += c;
  64             while (isdigit(c = m_Input[in++]))
  65                 m_Output += c;
  66             in--;
  67             return Tok_num;
  68         }
  69
  70         // quoted string?
  71         if (c == '"')
  72         {
  73             c = m_Input[in++];
  74             while ((c != '"') && !iscntrl(c)) {
  75                 // handle escaped characters
  76                 if (c == '\\')
  77                     m_Output += m_Input[in++];
  78                 else
  79                     m_Output += c;
  80                 c = m_Input[in++];
  81             }
  82             if (c == '"')
  83                 return Tok_str;
  84             return Tok_none;
  85         }
  86
  87         // normal string
  88         while (!isspace(c) && !iscntrl(c))
  89         {
  90             m_Output += c;
  91             c = m_Input[in++];
  92         }
  93         in--;
  94
  95         // command?
  96         if (m_Output.length() <= 4)
  97         {
  98             if (m_Output == "EXEC")
  99                 return Tok_exec;
 100             if (m_Output == "PASS")
 101                 return Tok_pass;
 102             if (m_Output == "DEL")
 103                 return Tok_delCmd;
 104             if (m_Output == "PING")
 105                 return Tok_ping;
 106             if (m_Output == "EXIT")
 107                 return Tok_exit;
 108             if (m_Output == "STOP")
 109                 return Tok_stop;
 110             if (m_Output == "SET")
 111                 return Tok_set;
 112             if (m_Output == "GET")
 113                 return Tok_get;
 114             if (m_Output == "HOST")
 115                 return Tok_host;
 116             if (m_Output == "SCHD")
 117                 return Tok_sched;
 118             if (m_Output == "PRIO")
 119                 return Tok_prio;
 120             if (m_Output == "DELV")
 121                 return Tok_delVar;
 122             if (m_Output == "DELG")
 123                 return Tok_delGroup;
 124             if (m_Output == "DELS")
 125                 return Tok_delSpecialKey;
 126         if (m_Output == "GETK")
 127         return Tok_getKeys;
 128         if (m_Output == "CHKG")
 129         return Tok_chkGroup;
 130         }
 131
 132         return Tok_str;
 133     }
 134 }
 135