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-rw-r--r--src/net/java/games/gluegen/StructLayout.java138
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diff --git a/src/net/java/games/gluegen/StructLayout.java b/src/net/java/games/gluegen/StructLayout.java
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+++ b/src/net/java/games/gluegen/StructLayout.java
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+/*
+ * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * - Redistribution of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistribution in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * Neither the name of Sun Microsystems, Inc. or the names of
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * This software is provided "AS IS," without a warranty of any kind. ALL
+ * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
+ * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
+ * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
+ * MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
+ * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
+ * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
+ * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
+ * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
+ * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
+ * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
+ * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+ *
+ * You acknowledge that this software is not designed or intended for use
+ * in the design, construction, operation or maintenance of any nuclear
+ * facility.
+ *
+ * Sun gratefully acknowledges that this software was originally authored
+ * and developed by Kenneth Bradley Russell and Christopher John Kline.
+ */
+
+package net.java.games.gluegen;
+
+import net.java.games.gluegen.cgram.types.*;
+
+public class StructLayout {
+ private int baseOffset;
+ private int structAlignment;
+
+ protected StructLayout(int baseOffset,
+ int structAlignment) {
+ this.baseOffset = baseOffset;
+ this.structAlignment = structAlignment;
+ }
+
+ public void layout(CompoundType t) {
+ int n = t.getNumFields();
+ int curOffset = baseOffset;
+ int maxSize = 0;
+ for (int i = 0; i < n; i++) {
+ Field f = t.getField(i);
+ Type ft = f.getType();
+ if (ft.isInt() || ft.isFloat() || ft.isDouble() || ft.isPointer()) {
+ int sz = ft.getSize();
+ if ((curOffset % sz) != 0) {
+ curOffset += sz - (curOffset % sz);
+ }
+ f.setOffset(curOffset);
+ if (t.isUnion()) {
+ maxSize = Math.max(maxSize, sz);
+ } else {
+ curOffset += sz;
+ }
+ } else if (ft.isCompound()) {
+ new StructLayout(0, structAlignment).layout(ft.asCompound());
+ if ((curOffset % structAlignment) != 0) {
+ curOffset += structAlignment - (curOffset % structAlignment);
+ }
+ f.setOffset(curOffset);
+ if (t.isUnion()) {
+ maxSize = Math.max(maxSize, ft.getSize());
+ } else {
+ curOffset += ft.getSize();
+ }
+ } else if (ft.isArray()) {
+ ArrayType arrayType = ft.asArray();
+ CompoundType compoundElementType = arrayType.getBaseElementType().asCompound();
+ if (compoundElementType != null) {
+ new StructLayout(0, structAlignment).layout(compoundElementType);
+ arrayType.recomputeSize();
+ }
+ // Note: not sure how this rounding is done
+ if ((curOffset % structAlignment) != 0) {
+ curOffset += structAlignment - (curOffset % structAlignment);
+ }
+ f.setOffset(curOffset);
+ curOffset += ft.getSize();
+ } else {
+ // FIXME
+ String name = t.getName();
+ if (name == null) {
+ name = t.toString();
+ }
+ throw new RuntimeException("Complicated field types (" + ft +
+ " " + f.getName() +
+ " in type " + name +
+ ") not implemented yet");
+ }
+ }
+ // FIXME: I think the below is wrong; better check with some examples
+ // if ((curOffset % structAlignment) != 0) {
+ // curOffset += structAlignment - (curOffset % structAlignment);
+ // }
+ if (t.isUnion()) {
+ t.setSize(maxSize);
+ } else {
+ t.setSize(curOffset);
+ }
+ }
+
+
+
+ public static StructLayout createForCurrentPlatform() {
+ String os = System.getProperty("os.name").toLowerCase();
+ String cpu = System.getProperty("os.arch").toLowerCase();
+ if ((os.startsWith("windows") && cpu.equals("x86")) ||
+ (os.startsWith("linux") && cpu.equals("i386")) ||
+ (os.startsWith("sunos") && cpu.equals("sparc")) ||
+ (os.startsWith("sunos") && cpu.equals("i386"))||
+ (os.startsWith("mac os") && cpu.equals("ppc"))
+ ) {
+ // FIXME: make struct alignment configurable? May need to change
+ // packing rules on a per-type basis?
+ return new StructLayout(0, 8);
+ } else {
+ // FIXME: add more ports
+ throw new RuntimeException("Please port StructLayout to your OS (" + os + ") and CPU (" + cpu + ")");
+ }
+ }
+}