UltimateZoneBuilder/Source/Core/ZDoom/ZDTextParser.cs

326 lines
8.3 KiB
C#

#region ================== Copyright (c) 2007 Pascal vd Heiden
/*
* Copyright (c) 2007 Pascal vd Heiden, www.codeimp.com
* This program is released under GNU General Public License
*
* 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.
*
*/
#endregion
#region ================== Namespaces
using System;
using System.Collections;
using System.Collections.Generic;
using System.Globalization;
using System.Text;
using CodeImp.DoomBuilder.IO;
using CodeImp.DoomBuilder.Data;
using System.IO;
using System.Diagnostics;
using CodeImp.DoomBuilder.Compilers;
#endregion
namespace CodeImp.DoomBuilder.ZDoom
{
public abstract class ZDTextParser
{
#region ================== Constants
#endregion
#region ================== Variables
// Parsing
protected string whitespace = "\n \t\r";
protected string specialtokens = ":{}+-\n;";
// Input data stream
protected Stream datastream;
protected BinaryReader datareader;
protected string sourcename;
// Error report
private int errorline;
private string errordesc;
private string errorsource;
#endregion
#region ================== Properties
internal Stream DataStream { get { return datastream; } }
internal BinaryReader DataReader { get { return datareader; } }
public int ErrorLine { get { return errorline; } }
public string ErrorDescription { get { return errordesc; } }
public string ErrorSource { get { return errorsource; } }
public bool HasError { get { return (errordesc != null); } }
#endregion
#region ================== Constructor / Disposer
// Constructor
protected ZDTextParser()
{
// Initialize
errordesc = null;
}
#endregion
#region ================== Parsing
// This parses the given decorate stream
// Returns false on errors
public virtual bool Parse(Stream stream, string sourcefilename)
{
datastream = stream;
datareader = new BinaryReader(stream, Encoding.ASCII);
sourcename = sourcefilename;
datastream.Seek(0, SeekOrigin.Begin);
return true;
}
// This returns true if the given character is whitespace
protected internal bool IsWhitespace(char c)
{
return (whitespace.IndexOf(c) > -1);
}
// This returns true if the given character is a special token
protected internal bool IsSpecialToken(char c)
{
return (specialtokens.IndexOf(c) > -1);
}
// This returns true if the given character is a special token
protected internal bool IsSpecialToken(string s)
{
if(s.Length > 0)
return (specialtokens.IndexOf(s[0]) > -1);
else
return false;
}
// This removes beginning and ending quotes from a token
protected internal string StripTokenQuotes(string token)
{
// Remove first character, if it is a quote
if(!string.IsNullOrEmpty(token) && (token[0] == '"'))
token = token.Substring(1);
// Remove last character, if it is a quote
if(!string.IsNullOrEmpty(token) && (token[token.Length - 1] == '"'))
token = token.Substring(0, token.Length - 1);
return token;
}
// This skips whitespace on the stream, placing the read
// position right before the first non-whitespace character
// Returns false when the end of the stream is reached
protected internal bool SkipWhitespace(bool skipnewline)
{
int offset = skipnewline ? 0 : 1;
char c;
do
{
if(datastream.Position == datastream.Length) return false;
c = (char)datareader.ReadByte();
// Check if this is comment
if(c == '/')
{
if(datastream.Position == datastream.Length) return false;
char c2 = (char)datareader.ReadByte();
if(c2 == '/')
{
// Check if not a special comment with a token
if(datastream.Position == datastream.Length) return false;
char c3 = (char)datareader.ReadByte();
if(c3 != '$')
{
// Skip entire line
char c4 = ' ';
while((c4 != '\n') && (datastream.Position < datastream.Length)) { c4 = (char)datareader.ReadByte(); }
c = c4;
}
else
{
// Not a comment
c = c3;
}
}
else if(c2 == '*')
{
// Skip until */
char c4, c3 = '\0';
do
{
c4 = c3;
c3 = (char)datareader.ReadByte();
}
while((c4 != '*') || (c3 != '/'));
c = ' ';
}
else
{
// Not a comment, rewind from reading c2
datastream.Seek(-1, SeekOrigin.Current);
}
}
}
while(whitespace.IndexOf(c, offset) > -1);
// Go one character back so we can read this non-whitespace character again
datastream.Seek(-1, SeekOrigin.Current);
return true;
}
// This reads a token (all sequential non-whitespace characters or a single character)
// Returns null when the end of the stream has been reached
protected internal string ReadToken()
{
string token = "";
bool quotedstring = false;
// Return null when the end of the stream has been reached
if(datastream.Position == datastream.Length) return null;
// Start reading
char c = (char)datareader.ReadByte();
while(!IsWhitespace(c) || quotedstring || IsSpecialToken(c))
{
// Special token?
if(!quotedstring && IsSpecialToken(c))
{
// Not reading a token yet?
if(token.Length == 0)
{
// This is our whole token
token += c;
break;
}
else
{
// This is a new token and shouldn't be read now
// Go one character back so we can read this token again
datastream.Seek(-1, SeekOrigin.Current);
break;
}
}
else
{
// Quote?
if(c == '"')
{
// Quote to end the string?
if(quotedstring) quotedstring = false;
// First character is a quote?
if(token.Length == 0) quotedstring = true;
token += c;
}
// Potential comment?
else if((c == '/') && !quotedstring)
{
// Check the next byte
if(datastream.Position == datastream.Length) return token;
char c2 = (char)datareader.ReadByte();
if((c2 == '/') || (c2 == '*'))
{
// This is a comment start, so the token ends here
// Go two characters back so we can read this comment again
datastream.Seek(-2, SeekOrigin.Current);
break;
}
else
{
// Not a comment
// Go one character back so we can read this char again
datastream.Seek(-1, SeekOrigin.Current);
token += c;
}
}
else
{
token += c;
}
}
// Next character
if(datastream.Position < datastream.Length)
c = (char)datareader.Read();
else
break;
}
return token;
}
// This reads the rest of the line
// Returns null when the end of the stream has been reached
protected internal string ReadLine()
{
string token = "";
// Return null when the end of the stream has been reached
if(datastream.Position == datastream.Length) return null;
// Start reading
char c = (char)datareader.ReadByte();
while(c != '\n')
{
token += c;
// Next character
if(datastream.Position < datastream.Length)
c = (char)datareader.Read();
else
break;
}
return token.Trim();
}
// This reports an error
protected internal void ReportError(string message)
{
long position = datastream.Position;
long readpos = 0;
int linenumber = 1;
// Find the line on which we found this error
datastream.Seek(0, SeekOrigin.Begin);
StreamReader textreader = new StreamReader(datastream, Encoding.ASCII);
while(readpos < position)
{
string line = textreader.ReadLine();
if(line == null) break;
readpos += line.Length + 2;
linenumber++;
}
// Return to original position
datastream.Seek(position, SeekOrigin.Begin);
// Set error information
errordesc = message;
errorline = linenumber;
errorsource = sourcename;
}
#endregion
}
}