add a new layout string parser to minimize the String garbage

1 files changed, 236 insertions, 0 deletions

diff --git a/src/jake2/client/LayoutParser.java b/src/jake2/client/LayoutParser.java
new file mode 100644
index 0000000..61e2def
--- /dev/null
+++ b/src/jake2/client/LayoutParser.java
@@ -0,0 +1,236 @@
+/*
+ * LayoutParser.java
+ * Copyright (C) 2003
+ */
+/*
+ Copyright (C) 1997-2001 Id Software, Inc.
+
+ 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+ */
+package jake2.client;
+
+import jake2.Defines;
+import jake2.qcommon.Com;
+
+final class LayoutParser {
+    int tokenPos;
+
+    int tokenLength;
+
+    int index;
+
+    int length;
+
+    String data;
+
+    LayoutParser() {
+	init(null);
+    }
+
+    public void init(String layout) {
+	tokenPos = 0;
+	tokenLength = 0;
+	index = 0;
+	data = (layout != null) ? layout : "";
+	length = (layout != null) ? layout.length() : 0;
+    }
+
+    public boolean hasNext() {
+	return !isEof();
+    }
+
+    public void next() {
+	if (data == null) {
+	    tokenLength = 0;
+	    return;
+	}
+
+	while (true) {
+	    // skip whitespace
+	    skipwhites();
+	    if (isEof()) {
+		tokenLength = 0;
+		return;
+	    }
+
+	    // skip // comments
+	    if (getchar() == '/') {
+		if (nextchar() == '/') {
+		    skiptoeol();
+		    // goto skip whitespace
+		    continue;
+		} else {
+		    prevchar();
+		    break;
+		}
+	    } else
+		break;
+	}
+
+	int c;
+	int len = 0;
+	// handle quoted strings specially
+	if (getchar() == '\"') {
+	    nextchar();
+	    tokenPos = index;
+	    while (true) {
+		c = getchar();
+		nextchar();
+		if (c == '\"' || c == 0) {
+		    tokenLength = len;
+		    return;
+		}
+		if (len < Defines.MAX_TOKEN_CHARS) {
+		    ++len;
+		}
+	    }
+	}
+
+	// parse a regular word
+	c = getchar();
+	tokenPos = index;
+	do {
+	    if (len < Defines.MAX_TOKEN_CHARS) {
+		++len;
+	    }
+	    c = nextchar();
+	} while (c > 32);
+
+	if (len == Defines.MAX_TOKEN_CHARS) {
+	    Com.Printf("Token exceeded " + Defines.MAX_TOKEN_CHARS
+		    + " chars, discarded.\n");
+	    len = 0;
+	}
+
+	tokenLength = len;
+	return;
+    }
+
+    public boolean tokenEquals(String other) {
+	if (tokenLength != other.length())
+	    return false;
+	return data.regionMatches(tokenPos, other, 0, tokenLength);
+    }
+
+    public int tokenAsInt() {
+	if (tokenLength == 0)
+	    return 0;
+	return atoi();
+    }
+
+    public String token() {
+	if (tokenLength == 0)
+	    return "";
+	return data.substring(tokenPos, tokenPos + tokenLength);
+    }
+
+    private int atoi() {
+	int result = 0;
+	boolean negative = false;
+	int i = 0, max = tokenLength;
+	String s = data;
+	int limit;
+	int multmin;
+	int digit;
+
+	if (max > 0) {
+	    if (s.charAt(tokenPos) == '-') {
+		negative = true;
+		limit = Integer.MIN_VALUE;
+		i++;
+	    } else {
+		limit = -Integer.MAX_VALUE;
+	    }
+	    multmin = limit / 10;
+	    if (i < max) {
+		digit = Character.digit(s.charAt(tokenPos + i++), 10);
+		if (digit < 0) {
+		    return 0; // wrong format
+		} else {
+		    result = -digit;
+		}
+	    }
+	    while (i < max) {
+		// Accumulating negatively avoids surprises near MAX_VALUE
+		digit = Character.digit(s.charAt(tokenPos + i++), 10);
+		if (digit < 0) {
+		    return 0; // wrong format
+		}
+		if (result < multmin) {
+		    return 0; // wrong format
+		}
+		result *= 10;
+		if (result < limit + digit) {
+		    return 0; // wrong format
+		}
+		result -= digit;
+	    }
+	} else {
+	    return 0; // wrong format
+	}
+	if (negative) {
+	    if (i > 1) {
+		return result;
+	    } else { /* Only got "-" */
+		return 0; // wrong format
+	    }
+	} else {
+	    return -result;
+	}
+    }
+
+    private char getchar() {
+	if (index < length) {
+	    return data.charAt(index);
+	}
+	return 0;
+    }
+
+    private char nextchar() {
+	++index;
+	if (index < length) {
+	    return data.charAt(index);
+	}
+	return 0;
+    }
+
+    private char prevchar() {
+	if (index > 0) {
+	    --index;
+	    return data.charAt(index);
+	}
+	return 0;
+    }
+
+    private boolean isEof() {
+	return index >= length;
+    }
+
+    private char skipwhites() {
+	char c = 0;
+	while (index < length && ((c = data.charAt(index)) <= ' ') && c != 0)
+	    ++index;
+	return c;
+    }
+
+    private char skiptoeol() {
+	char c = 0;
+	while (index < length && (c = data.charAt(index)) != '\n' && c != 0)
+	    ++index;
+	return c;
+    }
+}