Handle NULL in variable assignments and conditionals.

* org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/ASTParserUtil.java: New file.
* org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/PropertySimulator.java: Extract truth value parsing to ASTParserUtil.
* org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/VariableAssignmentVisitor.java: Check for NULL as "(void *) 0".

4 files changed, 63 insertions, 36 deletions

diff --git a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/ASTParserUtil.java b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/ASTParserUtil.java
new file mode 100644
index 0000000..0591464
--- /dev/null
+++ b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/ASTParserUtil.java
@@ -0,0 +1,56 @@
+/*******************************************************************************
+ * Copyright (c) 2009 Elliott Baron
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Elliott Baron - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.codan.extension;
+
+import org.eclipse.cdt.core.dom.ast.ASTTypeUtil;
+import org.eclipse.cdt.core.dom.ast.IASTCastExpression;
+import org.eclipse.cdt.core.dom.ast.IASTExpression;
+import org.eclipse.cdt.core.dom.ast.IASTLiteralExpression;
+import org.eclipse.cdt.core.dom.ast.IASTTypeId;
+import org.eclipse.cdt.core.dom.ast.IASTUnaryExpression;
+
+public class ASTParserUtil {
+
+	public static Boolean getTruthValue(IASTExpression valueExpr) {
+		Boolean result = null;
+		// Handle assignment from literals
+		result = getLiteralTruth(valueExpr);
+		// Handle NULL assignment, assume NULL is defined as (void *)0
+		if (valueExpr instanceof IASTUnaryExpression) {
+			IASTExpression op = ((IASTUnaryExpression) valueExpr).getOperand();
+			if (op instanceof IASTCastExpression) {
+				IASTCastExpression castExpr = (IASTCastExpression) op;
+				IASTTypeId castType = castExpr.getTypeId();
+				String typeString = ASTTypeUtil.getType(castType);
+				if (typeString.equals("void *")) {
+					result = getLiteralTruth(castExpr.getOperand());
+				}				
+			}
+		}
+		// TODO other variable assignments
+		return result;
+	}
+
+	private static Boolean getLiteralTruth(IASTExpression valueExpr) {
+		Boolean result = null;
+		if (valueExpr instanceof IASTLiteralExpression) {
+			int kind = ((IASTLiteralExpression) valueExpr).getKind();
+			String value = String.valueOf(((IASTLiteralExpression) valueExpr).getValue());
+			switch (kind) {
+			case IASTLiteralExpression.lk_integer_constant:
+				// 0 = False, > 0 = True
+				result = !value.equals("0");
+			}
+		}
+		return result;
+	}
+	
+}
diff --git a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/PropertySimulator.java b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/PropertySimulator.java
index 80e393f..655dca2 100644
--- a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/PropertySimulator.java
+++ b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/PropertySimulator.java
@@ -401,7 +401,7 @@ public class PropertySimulator {
 		IBinding binding = name.resolveBinding();
 		if (binding instanceof IVariable) {
 			IVariable var = (IVariable) binding;
-			Boolean truth = getTruthValue(valueExpr);
+			Boolean truth = ASTParserUtil.getTruthValue(valueExpr);
 			if (truth != null) {
 				clause = new ExecutionStateClause(var, truth == branchTruth);
 			}
@@ -417,20 +417,4 @@ public class PropertySimulator {
 		}
 		return clause;
 	}
-
-	private Boolean getTruthValue(IASTExpression valueExpr) {
-		Boolean result = null;
-		// Handle assignment from literals
-		if (valueExpr instanceof IASTLiteralExpression) {
-			int kind = ((IASTLiteralExpression) valueExpr).getKind();
-			String value = String.valueOf(((IASTLiteralExpression) valueExpr).getValue());
-			switch (kind) {
-			case IASTLiteralExpression.lk_integer_constant:
-				// 0 = False, > 0 = True
-				result = !value.equals("0");
-			}
-		}
-		// TODO other variable assignments
-		return result;
-	}
 }
diff --git a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/VariableAssignmentVisitor.java b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/VariableAssignmentVisitor.java
index c167129..28c12f2 100644
--- a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/VariableAssignmentVisitor.java
+++ b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/VariableAssignmentVisitor.java
@@ -1,7 +1,9 @@
 package org.eclipse.cdt.codan.extension;
 
+import org.eclipse.cdt.core.dom.ast.ASTTypeUtil;
 import org.eclipse.cdt.core.dom.ast.ASTVisitor;
 import org.eclipse.cdt.core.dom.ast.IASTBinaryExpression;
+import org.eclipse.cdt.core.dom.ast.IASTCastExpression;
 import org.eclipse.cdt.core.dom.ast.IASTDeclarator;
 import org.eclipse.cdt.core.dom.ast.IASTExpression;
 import org.eclipse.cdt.core.dom.ast.IASTIdExpression;
@@ -10,6 +12,8 @@ import org.eclipse.cdt.core.dom.ast.IASTInitializerExpression;
 import org.eclipse.cdt.core.dom.ast.IASTLiteralExpression;
 import org.eclipse.cdt.core.dom.ast.IASTName;
 import org.eclipse.cdt.core.dom.ast.IASTNode;
+import org.eclipse.cdt.core.dom.ast.IASTTypeId;
+import org.eclipse.cdt.core.dom.ast.IASTUnaryExpression;
 import org.eclipse.cdt.core.dom.ast.IBinding;
 import org.eclipse.cdt.core.dom.ast.IVariable;
 import org.eclipse.ptp.pldt.mpi.analysis.cdt.graphs.IBlock;
@@ -72,27 +76,10 @@ public class VariableAssignmentVisitor extends ASTVisitor {
 		IBinding binding = name.resolveBinding();
 		if (binding instanceof IVariable) {
 			IVariable var = (IVariable) binding;
-			Boolean truth = getTruthValue(valueExpr);
+			Boolean truth = ASTParserUtil.getTruthValue(valueExpr);
 			if (truth != null) {
 				es.addTruthAssignment(var, truth, blk);
 			}
 		}
 	}
-
-	private Boolean getTruthValue(IASTExpression valueExpr) {
-		Boolean result = null;
-		// Handle assignment from literals
-		if (valueExpr instanceof IASTLiteralExpression) {
-			int kind = ((IASTLiteralExpression) valueExpr).getKind();
-			String value = String.valueOf(((IASTLiteralExpression) valueExpr).getValue());
-			switch (kind) {
-			case IASTLiteralExpression.lk_integer_constant:
-				// 0 = False, > 0 = True
-				result = !value.equals("0");
-			}
-		}
-		// TODO other variable assignments
-		return result;
-	}
-
 }
diff --git a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/checkers/AbstractOpenCloseChecker.java b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/checkers/AbstractOpenCloseChecker.java
index 482c5ad..6bc453c 100644
--- a/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/checkers/AbstractOpenCloseChecker.java
+++ b/org.eclipse.cdt.codan.extension/src/org/eclipse/cdt/codan/extension/checkers/AbstractOpenCloseChecker.java
@@ -57,7 +57,7 @@ public abstract class AbstractOpenCloseChecker extends AbstractIndexAstChecker {
 		if (resources != null && resources.length > 0) {
 			IResource res = resources[0];
 
-			// Create call graph for project
+			// Create call graph for resource
 			ICallGraph cg = creator.createCallGraph(res);
 			creator.computeCallGraph(cg);