/*
* This program source code file is part of KICAD, a free EDA CAD application.
*
* Copyright (C) 2007-2010 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
* Copyright (C) 2007 Kicad Developers, see change_log.txt for contributors.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#ifndef _DSNLEXER_H
#define _DSNLEXER_H
#include <cstdio>
#include <string>
#include "fctsys.h"
#include "pcbnew.h"
#include "richio.h"
/**
* Struct KEYWORD
* holds a keyword string and its unique integer token.
*/
struct KEYWORD
{
const char* name; ///< unique keyword.
int token; ///< a zero based index into an array of KEYWORDs
};
// something like this macro can be used to help initialize a KEYWORD table.
// see SPECCTRA_DB::keywords[] as an example.
//#define TOKDEF(x) { #x, T_##x }
/**
* Enum DSN_SYNTAX_T
* lists all the DSN lexer's tokens that are supported in lexing. It is up
* to the parser if it wants also to support them.
*/
enum DSN_SYNTAX_T {
DSN_NONE = -11,
DSN_COMMENT = -10,
DSN_STRING_QUOTE = -9,
DSN_QUOTE_DEF = -8,
DSN_DASH = -7,
DSN_SYMBOL = -6,
DSN_NUMBER = -5,
DSN_RIGHT = -4, // right bracket, ')'
DSN_LEFT = -3, // left bracket, '('
DSN_STRING = -2, // a quoted string, stripped of the quotes
DSN_EOF = -1, // special case for end of file
};
/**
* Class DLEXER
* implements a lexical analyzer for the SPECCTRA DSN file format. It
* reads lexical tokens from the current LINE_READER through the NextTok()
* function. The NextTok() function returns one of the DSN_T values.
*/
class DSNLEXER
{
char* next;
char* start;
char* limit;
LINE_READER reader;
int stringDelimiter;
bool space_in_quoted_tokens; ///< blank spaces within quoted strings
bool comments_are_tokens; ///< true if should return comments as tokens
wxString filename;
int prevTok; ///< curTok from previous NextTok() call.
int curOffset; ///< offset within current line of the current token
int curTok; ///< the current token obtained on last NextTok()
std::string curText; ///< the text of the current token
std::string lowercase; ///< a scratch buf holding token in lowercase
const KEYWORD* keywords;
unsigned keywordCount;
int readLine() throw (IOError)
{
int len = reader.ReadLine();
next = start;
limit = start + len;
return len;
}
/**
* Function readLineOrCmt
* reads a line from the LINE_READER and returns either:
* <ol>
* <li> a positive line length (a +1 if empty line)
* <li> zero of end of file.
* <li> DSN_COMMENT if the line is a comment
* </ol>
*/
int readLineOrCmt();
/**
* Function findToken
* takes a string and looks up the string in the list of expected
* tokens.
*
* @param tok A string holding the token text to lookup, in an
* unpredictable case: uppercase or lowercase
* @return int - DSN_T or -1 if argument string is not a recognized token.
*/
int findToken( const std::string& tok );
bool isStringTerminator( char cc )
{
if( !space_in_quoted_tokens && cc==' ' )
return true;
if( cc == stringDelimiter )
return true;
return false;
}
public:
/**
* Constructor DSNLEXER
* intializes a DSN lexer and prepares to read from aFile which
* is already open and has aFilename.
*
* @param aKeywordTable is an array of KEYWORDS holding \a aKeywordCount. This
* token table need not contain the lexer separators such as '(' ')', etc.
* @param aKeywordTable is the count of tokens in aKeywordTable.
*/
DSNLEXER( FILE* aFile, const wxString& aFilename,
const KEYWORD* aKeywordTable, unsigned aKeywordCount );
/**
* Function SetStringDelimiter
* changes the string delimiter from the default " to some other character
* and returns the old value.
* @param aStringDelimiter The character in lowest 8 bits.
* @return int - The old delimiter in the lowest 8 bits.
*/
int SetStringDelimiter( int aStringDelimiter )
{
int old = stringDelimiter;
stringDelimiter = aStringDelimiter;
return old;
}
/**
* Function SetSpaceInQuotedTokens
* changes the setting controlling whether a space in a quoted string is
* a terminator.
* @param val If true, means
*/
bool SetSpaceInQuotedTokens( bool val )
{
bool old = space_in_quoted_tokens;
space_in_quoted_tokens = val;
return old;
}
/**
* Function SetCommentsAreTokens
* changes the handling of comments. If set true, comments are returns
* as single line strings with a terminating newline, else they are
* consumed by the lexer and not returned.
*/
bool SetCommentsAreTokens( bool val )
{
bool old = comments_are_tokens;
comments_are_tokens = val;
return old;
}
/**
* Function NextTok
* returns the next token found in the input file or T_EOF when reaching
* the end of file.
* @return int - the type of token found next.
* @throw IOError - only if the LINE_READER throws it.
*/
int NextTok() throw (IOError);
/**
* Function ThrowIOError
* encapsulates the formatting of an error message which contains the exact
* location within the input file of something the caller is rejecting.
*/
void ThrowIOError( wxString aText, int charOffset ) throw (IOError);
/**
* Function GetTokenString
* returns the C string representation of a DSN_T value.
*/
const char* GetTokenText( int aTok );
static const char* Syntax( int aTok );
/**
* Function CurText
* returns a pointer to the current token's text.
*/
const char* CurText()
{
return curText.c_str();
}
/**
* Function CurTok
* returns whatever NextTok() returned the last time it was called.
*/
int CurTok()
{
return curTok;
}
/**
* Function CurLineNumber
* returns the current line number within my LINE_READER
*/
int CurLineNumber()
{
return reader.LineNumber();
}
/**
* Function CurFilename
* returns the current input filename.
* @return const wxString& - the filename.
*/
const wxString& CurFilename()
{
return filename;
}
/**
* Function PrevTok
* returns whatever NextTok() returned the 2nd to last time it was called.
*/
int PrevTok()
{
return prevTok;
}
/**
* Function CurOffset
* returns the char offset within the current line, using a 1 based index.
* @return int - a one based index into the current line.
*/
int CurOffset()
{
return curOffset + 1;
}
};
#endif // _DSNLEXER_H