KDESu

lexer.cpp
1 /* vi: ts=8 sts=4 sw=4
2 
3  This file is part of the KDE project, module kdesu.
4  SPDX-FileCopyrightText: 1999, 2000 Geert Jansen <[email protected]>
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 Lexer::Lexer(const QByteArray &input)
15 {
16  m_Input = input;
17  in = 0;
18 }
19 
20 Lexer::~Lexer()
21 {
22  // Erase buffers
23  m_Input.fill('x');
24  m_Output.fill('x');
25 }
26 
28 {
29  return m_Output;
30 }
31 
32 /*
33  * lex() is the lexer. There is no end-of-input check here so that has to be
34  * done by the caller.
35  */
36 
38 {
39  char c;
40 
41  c = m_Input[in++];
42  m_Output.fill('x');
43  m_Output.resize(0);
44 
45  while (1) {
46  // newline?
47  if (c == '\n') {
48  return '\n';
49  }
50 
51  // No control characters
52  if (iscntrl(c)) {
53  return Tok_none;
54  }
55 
56  if (isspace(c)) {
57  while (isspace(c = m_Input[in++])) {
58  ;
59  }
60  }
61 
62  // number?
63  if (isdigit(c)) {
64  m_Output += c;
65  while (isdigit(c = m_Input[in++])) {
66  m_Output += c;
67  }
68  in--;
69  return Tok_num;
70  }
71 
72  // quoted string?
73  if (c == '"') {
74  c = m_Input[in++];
75  while ((c != '"') && !iscntrl(c)) {
76  // handle escaped characters
77  if (c == '\\') {
78  c = m_Input[in++];
79  if (iscntrl(c)) {
80  return Tok_none;
81  }
82  if (c == '^') {
83  c = m_Input[in++];
84  if ((c == '"') || iscntrl(c)) {
85  return Tok_none;
86  }
87  m_Output += c - '@';
88  } else {
89  m_Output += c;
90  }
91  } else {
92  m_Output += c;
93  }
94  c = m_Input[in++];
95  }
96  if (c == '"') {
97  return Tok_str;
98  }
99  return Tok_none;
100  }
101 
102  // normal string
103  while (!isspace(c) && !iscntrl(c)) {
104  m_Output += c;
105  c = m_Input[in++];
106  }
107  in--;
108 
109  // command?
110  if (m_Output.length() <= 4) {
111  if (m_Output == "EXEC") {
112  return Tok_exec;
113  }
114  if (m_Output == "PASS") {
115  return Tok_pass;
116  }
117  if (m_Output == "DEL") {
118  return Tok_delCmd;
119  }
120  if (m_Output == "PING") {
121  return Tok_ping;
122  }
123  if (m_Output == "EXIT") {
124  return Tok_exit;
125  }
126  if (m_Output == "STOP") {
127  return Tok_stop;
128  }
129  if (m_Output == "SET") {
130  return Tok_set;
131  }
132  if (m_Output == "GET") {
133  return Tok_get;
134  }
135  if (m_Output == "HOST") {
136  return Tok_host;
137  }
138  if (m_Output == "SCHD") {
139  return Tok_sched;
140  }
141  if (m_Output == "PRIO") {
142  return Tok_prio;
143  }
144  if (m_Output == "DELV") {
145  return Tok_delVar;
146  }
147  if (m_Output == "DELG") {
148  return Tok_delGroup;
149  }
150  if (m_Output == "DELS") {
151  return Tok_delSpecialKey;
152  }
153  if (m_Output == "GETK") {
154  return Tok_getKeys;
155  }
156  if (m_Output == "CHKG") {
157  return Tok_chkGroup;
158  }
159  }
160 
161  return Tok_str;
162  }
163 }
QByteArray & lval()
Return the token's value.
Definition: lexer.cpp:27
QByteArray & fill(char ch, int size)
int lex()
Read next token.
Definition: lexer.cpp:37
void resize(int size)
int length() const const
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