The CondParser Class Reference

Copyright (C) 1997-2015 by Dimitri van Heesch. More...

Declaration

class CondParser { ... }

Included Headers

#include <src/condparser.h>

Enumerations Index

enum	TOKENTYPE { ... }
enum	OPERATOR_ID { ... }

Public Constructors Index

	CondParser ()

Public Member Functions Index

bool	parse (const QCString &fileName, int lineNr, const QCString &expr)
	Copyright (C) 1997-2015 by Dimitri van Heesch. More...

Private Member Functions Index

void	getToken ()
	Get next token in the current string expr. More...
bool	parseLevel1 ()
	conditional operators AND and OR More...
bool	parseLevel2 ()
	NOT. More...
bool	parseLevel3 ()
	parenthesized expression or variable More...
bool	parseVar ()
bool	evalOperator (const int opId, bool lhs, bool rhs)
	evaluate an operator for given values More...
bool	evalVariable (const QCString &varName)
	evaluate a variable More...
int	getOperatorId (const QCString &opName)
	returns the id of the given operator returns -1 if the operator is not recognized More...

Private Member Attributes Index

QCString	m_err
	error state More...
QCString	m_expr
	holds the expression More...
const char *	m_e
	points to a character in expr More...
QCString	m_token
	holds the token More...
TOKENTYPE	m_tokenType
	type of the token More...

Description

Copyright (C) 1997-2015 by Dimitri van Heesch.

Permission to use, copy, modify, and distribute this software and its documentation under the terms of the GNU General Public License is hereby granted. No representations are made about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. See the GNU General Public License for more details.

Documents produced by Doxygen are derivative works derived from the input used in their production; they are not affected by this license.

C++ Expression parser for ENABLED_SECTIONS in Doxygen

Features used: Operators: && AND operator || OR operator ! NOT operator

Definition at line 27 of file condparser.h.

Enumerations

OPERATOR_ID

enum CondParser::OPERATOR_ID

Enumeration values

UNKNOWN_OP	(= -1)
AND	(= 1)
OR
NOT

Definition at line 43 of file condparser.h.

44 {

45 UNKNOWN_OP = -1,

46 AND = 1,

47 OR,

48 NOT

49 };

TOKENTYPE

enum CondParser::TOKENTYPE

Enumeration values

NOTHING	(= -1)
DELIMITER
VARIABLE
UNKNOWN

Definition at line 36 of file condparser.h.

37 {

38 NOTHING = -1,

39 DELIMITER,

40 VARIABLE,

41 UNKNOWN

42 };

Public Constructors

CondParser()

CondParser::CondParser ()

inline

Definition at line 31 of file condparser.h.

31 CondParser() : m_e(nullptr), m_tokenType(NOTHING) {}

References m_e, m_tokenType and NOTHING.

Public Member Functions

parse()

bool CondParser::parse (const QCString & fileName, int lineNr, const QCString & expr)

Copyright (C) 1997-2015 by Dimitri van Heesch.

Permission to use, copy, modify, and distribute this software and its documentation under the terms of the GNU General Public License is hereby granted. No representations are made about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty. See the GNU General Public License for more details.

Documents produced by Doxygen are derivative works derived from the input used in their production; they are not affected by this license.

C++ Expression parser for ENABLED_SECTIONS in Doxygen

Features used: Operators: && AND operator || OR operator ! NOT operator parses and evaluates the given expression.

Returns

• On error, an error message is returned.
• On success, the result of the expression is either "1" or "0".

Declaration at line 32 of file condparser.h, definition at line 36 of file condparser.cpp.

36bool CondParser::parse(const QCString &fileName,int lineNr,const QCString &expr)

37{

38 if (expr.isEmpty()) return false;

39 m_expr = expr;

40 m_tokenType = NOTHING;

41

42 // initialize all variables

43 m_e = m_expr.data(); // let m_e point to the start of the expression

44

45 bool answer=false;

46 getToken();

47 if (m_tokenType==DELIMITER && m_token.isEmpty())

48 {

49 // empty expression: answer==FALSE

50 }

51 else if (m_err.isEmpty())

52 {

53 answer = parseLevel1();

54 }

55 if (!m_err.isEmpty())

56 {

57 warn(fileName,lineNr,"problem evaluating expression '{}': {}", expr, m_err);

58 }

59 //printf("expr='%s' answer=%d\n",expr,answer);

60 return answer;

61}

References DELIMITER, getToken, QCString::isEmpty, m_e, m_err, m_expr, m_token, m_tokenType, NOTHING, parseLevel1 and warn.

Referenced by handleGuard, startCondSection and startCondSection.

Private Member Functions

evalOperator()

bool CondParser::evalOperator (const int opId, bool lhs, bool rhs)

evaluate an operator for given values

Declaration at line 70 of file condparser.h, definition at line 263 of file condparser.cpp.

263bool CondParser::evalOperator(int opId, bool lhs, bool rhs)

264{

265 switch (opId)

266 {

267 // level 2

268 case AND: return lhs && rhs;

269 case OR: return lhs || rhs;

270 }

271

272 m_err = "Internal error unknown operator: id="+QCString().setNum(opId);

273 return FALSE;

274}

References AND, FALSE, m_err, OR and QCString::setNum.

Referenced by parseLevel1.

evalVariable()

bool CondParser::evalVariable (const QCString & varName)

evaluate a variable

Declaration at line 71 of file condparser.h, definition at line 279 of file condparser.cpp.

279bool CondParser::evalVariable(const QCString &varName)

280{

281 const StringVector &list = Config_getList(ENABLED_SECTIONS);

282 return std::find(list.begin(),list.end(),varName.str())!=list.end();

283}

References Config_getList and QCString::str.

Referenced by parseVar.

getOperatorId()

int CondParser::getOperatorId (const QCString & opName)

returns the id of the given operator returns -1 if the operator is not recognized

Declaration at line 72 of file condparser.h, definition at line 90 of file condparser.cpp.

90int CondParser::getOperatorId(const QCString &opName)

91{

92 // level 2

93 if (opName=="&&") { return AND; }

94 if (opName=="||") { return OR; }

95

96 // not operator

97 if (opName=="!") { return NOT; }

98

99 return UNKNOWN_OP;

100}

References AND, NOT, OR and UNKNOWN_OP.

Referenced by parseLevel1 and parseLevel2.

getToken()

void CondParser::getToken ()

Get next token in the current string expr.

Uses the data in m_expr pointed to by m_e to produce m_tokenType and m_token, set m_err in case of an error

Declaration at line 63 of file condparser.h, definition at line 107 of file condparser.cpp.

107void CondParser::getToken()

108{

109 m_tokenType = NOTHING;

110 m_token.clear();

111

112 //printf("\tgetToken e:{%c}, ascii=%i, col=%i\n", *e, *e, e-expr);

113

114 // skip over whitespaces

115 while (*m_e == ' ' || *m_e == '\t' || *m_e == '\n') // space or tab or newline

116 {

117 m_e++;

118 }

119

120 // check for end of expression

121 if (*m_e=='\0')

122 {

123 // token is still empty

124 m_tokenType = DELIMITER;

125 return;

126 }

127

128 // check for parentheses

129 if (*m_e == '(' || *m_e == ')')

130 {

131 m_tokenType = DELIMITER;

132 m_token += *m_e++;

133 return;

134 }

135

136 // check for operators (delimiters)

137 if (isDelimiter(*m_e))

138 {

139 m_tokenType = DELIMITER;

140 while (isDelimiter(*m_e))

141 {

142 m_token += *m_e++;

143 }

144 return;

145 }

146

147 // check for variables

148 if (isAlpha(*m_e))

149 {

150 m_tokenType = VARIABLE;

151 while (isAlphaNumSpec(*m_e))

152 {

153 m_token += *m_e++;

154 }

155 return;

156 }

157

158 // something unknown is found, wrong characters -> a syntax error

159 m_tokenType = UNKNOWN;

160 while (*m_e)

161 {

162 m_token += *m_e++;

163 }

164 m_err = QCString("Syntax error in part '")+m_token+"'";

165 return;

166}

References DELIMITER, isAlpha, isAlphaNumSpec, isDelimiter, m_e, m_err, m_token, m_tokenType, NOTHING, UNKNOWN and VARIABLE.

Referenced by parse, parseLevel1, parseLevel2, parseLevel3 and parseVar.

parseLevel1()

bool CondParser::parseLevel1 ()

conditional operators AND and OR

Declaration at line 65 of file condparser.h, definition at line 172 of file condparser.cpp.

172bool CondParser::parseLevel1()

173{

174 bool ans = parseLevel2();

175 int opId = getOperatorId(m_token);

176

177 while (opId==AND || opId==OR)

178 {

179 getToken();

180 ans = evalOperator(opId, ans, parseLevel2());

181 opId = getOperatorId(m_token);

182 }

183

184 return ans;

185}

References AND, evalOperator, getOperatorId, getToken, m_token, OR and parseLevel2.

Referenced by parse and parseLevel3.

parseLevel2()

bool CondParser::parseLevel2 ()

NOT.

Declaration at line 66 of file condparser.h, definition at line 190 of file condparser.cpp.

190bool CondParser::parseLevel2()

191{

192 int opId = getOperatorId(m_token);

193 if (opId == NOT)

194 {

195 getToken();

196 return !parseLevel3();

197 }

198 else

199 {

200 return parseLevel3();

201 }

202}

References getOperatorId, getToken, m_token, NOT and parseLevel3.

Referenced by parseLevel1.

parseLevel3()

bool CondParser::parseLevel3 ()

parenthesized expression or variable

Declaration at line 67 of file condparser.h, definition at line 208 of file condparser.cpp.

208bool CondParser::parseLevel3()

209{

210 // check if it is a parenthesized expression

211 if (m_tokenType == DELIMITER)

212 {

213 if (m_token=="(")

214 {

215 getToken();

216 bool ans = parseLevel1();

217 if (m_tokenType!=DELIMITER || m_token!=")")

218 {

219 m_err="Parenthesis ) missing";

220 return FALSE;

221 }

222 getToken();

223 return ans;

224 }

225 }

226

227 // if not parenthesized then the expression is a variable

228 return parseVar();

229}

References DELIMITER, FALSE, getToken, m_err, m_token, m_tokenType, parseLevel1 and parseVar.

Referenced by parseLevel2.

parseVar()

bool CondParser::parseVar ()

Declaration at line 68 of file condparser.h, definition at line 232 of file condparser.cpp.

232bool CondParser::parseVar()

233{

234 bool ans = false;

235 switch (m_tokenType)

236 {

237 case VARIABLE:

238 // this is a variable

239 ans = evalVariable(m_token);

240 getToken();

241 break;

242

243 default:

244 // syntax error or unexpected end of expression

245 if (m_token.isEmpty())

246 {

247 m_err="Unexpected end of expression";

248 return FALSE;

249 }

250 else

251 {

252 m_err="Value expected";

253 return FALSE;

254 }

255 break;

256 }

257 return ans;

258}

References evalVariable, FALSE, getToken, m_err, m_token, m_tokenType and VARIABLE.

Referenced by parseLevel3.

Private Member Attributes

m_e

const char* CondParser::m_e

points to a character in expr

Definition at line 56 of file condparser.h.

56 const char *m_e; //!< points to a character in expr

Referenced by CondParser, getToken and parse.

m_err

QCString CondParser::m_err

error state

Definition at line 54 of file condparser.h.

54 QCString m_err; //!< error state

Referenced by evalOperator, getToken, parse, parseLevel3 and parseVar.

m_expr

QCString CondParser::m_expr

holds the expression

Definition at line 55 of file condparser.h.

55 QCString m_expr; //!< holds the expression

Referenced by parse.

m_token

QCString CondParser::m_token

holds the token

Definition at line 58 of file condparser.h.

58 QCString m_token; //!< holds the token

Referenced by getToken, parse, parseLevel1, parseLevel2, parseLevel3 and parseVar.

m_tokenType

TOKENTYPE CondParser::m_tokenType

type of the token

Definition at line 59 of file condparser.h.

59 TOKENTYPE m_tokenType; //!< type of the token

Referenced by CondParser, getToken, parse, parseLevel3 and parseVar.

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The documentation for this class was generated from the following files:

• condparser.cpp
• condparser.h

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