Adding new operator call expression

Fraunhofer-AISEC · Jul 1, 2024 · 3924bb5 · 3924bb5
1 parent a52bc60
commit 3924bb5
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Showing 5 changed files with 23 additions and 14 deletions.
diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/ExpressionBuilder.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/graph/ExpressionBuilder.kt
@@ -293,11 +293,10 @@ fun MetadataProvider.newOperatorCallExpression(
     rawNode: Any? = null
 ): OperatorCallExpression {
     val node = OperatorCallExpression()
-    node.applyMetadata(
-        this,
-        operatorCode,
-        rawNode
-    )
+    node.applyMetadata(this, operatorCode, rawNode)
+
+    node.operatorCode = operatorCode
+    node.callee = callee
 
     log(node)
     return node

diff --git a/...ain/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/OperatorCallExpression.kt b/...ain/kotlin/de/fraunhofer/aisec/cpg/graph/statements/expressions/OperatorCallExpression.kt
@@ -25,6 +25,7 @@
  */
 package de.fraunhofer.aisec.cpg.graph.statements.expressions
 
+import de.fraunhofer.aisec.cpg.graph.HasBase
 import de.fraunhofer.aisec.cpg.graph.HasOperatorCode
 import de.fraunhofer.aisec.cpg.graph.Name
 import de.fraunhofer.aisec.cpg.graph.declarations.OperatorDeclaration
@@ -34,11 +35,21 @@ import de.fraunhofer.aisec.cpg.graph.declarations.OperatorDeclaration
  * In this case, we replace the original [BinaryOperator] with an [OperatorCallExpression], which
  * points to its respective [OperatorDeclaration].
  */
-class OperatorCallExpression : CallExpression(), HasOperatorCode {
+class OperatorCallExpression : CallExpression(), HasOperatorCode, HasBase {
 
-    override val operatorCode: String? = null
+    override var operatorCode: String? = null
 
     override var name: Name
         get() = Name(operatorCode ?: "")
         set(_) {}
+
+    /**
+     * The base object. This is basically a shortcut to accessing the base of the [callee], if it
+     * has one (i.e., if it implements [HasBase]). This is the case for example, if it is a
+     * [MemberExpression].
+     */
+    override val base: Expression?
+        get() {
+            return (callee as? HasBase)?.base
+        }
 }
diff --git a/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/passes/SymbolResolver.kt b/cpg-core/src/main/kotlin/de/fraunhofer/aisec/cpg/passes/SymbolResolver.kt
@@ -448,10 +448,6 @@ open class SymbolResolver(ctx: TranslationContext) : ComponentPass(ctx) {
                     .filterIsInstance<OperatorDeclaration>()
                     .singleOrNull()
 
-            // We unfortunately, have no direct access to the AST parent, but this is a very good
-            // heuristic to get it
-            var parent = reference.base.prevEOG.singleOrNull()
-
             if (op != null) {
                 type = op.returnTypes.singleOrNull()?.root ?: unknownType()
 
@@ -460,7 +456,8 @@ open class SymbolResolver(ctx: TranslationContext) : ComponentPass(ctx) {
                     newMemberExpression(op.name, reference.base, operatorCode = ".")
                         .implicit(op.name.localName, location = reference.location)
                 ref.refersTo = op
-                var call = newOperatorCallExpression(operatorCode = ".", ref).codeAndLocationFrom(ref)
+                var call =
+                    newOperatorCallExpression(operatorCode = "->", ref).codeAndLocationFrom(ref)
                 call.invokes = listOf(op)
 
                 // Make the call our new base

diff --git a/cpg-language-cxx/src/test/kotlin/de/fraunhofer/aisec/cpg/frontends/cxx/CXXDeclarationTest.kt b/cpg-language-cxx/src/test/kotlin/de/fraunhofer/aisec/cpg/frontends/cxx/CXXDeclarationTest.kt
@@ -30,7 +30,7 @@ import de.fraunhofer.aisec.cpg.graph.declarations.FunctionDeclaration
 import de.fraunhofer.aisec.cpg.graph.statements.ReturnStatement
 import de.fraunhofer.aisec.cpg.graph.statements.expressions.BinaryOperator
 import de.fraunhofer.aisec.cpg.graph.statements.expressions.Block
-import de.fraunhofer.aisec.cpg.graph.statements.expressions.MemberCallExpression
+import de.fraunhofer.aisec.cpg.graph.statements.expressions.OperatorCallExpression
 import de.fraunhofer.aisec.cpg.graph.statements.expressions.UnaryOperator
 import de.fraunhofer.aisec.cpg.graph.types.FunctionPointerType
 import de.fraunhofer.aisec.cpg.test.*
@@ -280,7 +280,7 @@ class CXXDeclarationTest {
         // we should now have an implicit call to our operator in-between "p" and "size"
         val opCall = sizeRef.base
         assertNotNull(opCall)
-        assertIs<MemberCallExpression>(opCall)
+        assertIs<OperatorCallExpression>(opCall)
         assertEquals(p, opCall.base)
         assertInvokes(opCall, op)
     }

diff --git a/cpg-language-cxx/src/test/resources/cxx/operators/member_access.cpp b/cpg-language-cxx/src/test/resources/cxx/operators/member_access.cpp
@@ -19,4 +19,6 @@ class Proxy {
 int main() {
     Proxy p;
     int size = p->size;
+
+    // int another_size = p.operator->()->size;
 }