Incorporate changes for INT36-C

Author: jeongsoolee09

c/cert/src/rules/INT36-C/ConvertingAPointerToIntegerOrIntegerToPointer.ql

@@ -17,85 +17,59 @@ class LiteralZero extends Literal {
   LiteralZero() { this.getValue() = "0" }
 }
 
-class StdIntIntPtrType extends IntPointerType {
+class StdIntIntPtrType extends Type {
   StdIntIntPtrType() {
-    this.getFile().(HeaderFile).getBaseName() = "stdint.h" and
-    this.getName().regexpMatch("u?intptr_t")
-  }
-}
+    exists(TypeDeclarationEntry entry |
+      /*
+       * Just check if there is a header file,
+       * because we don't know what header file the declaration might live in
+       */
 
-/* 1. Declaring an integer variable to hold a pointer value or the opposite, excluding compliant exceptions */
-predicate integerVariableWithPointerValue(Variable var, string message) {
-  (
-    // Declaring an integer variable to hold a pointer value
-    var.getUnderlyingType() instanceof IntType and
-    var.getAnAssignedValue().getUnderlyingType() instanceof PointerType and
-    message =
-      "Integer variable " + var + " is declared as an expression " + var.getAnAssignedValue() +
-        ", which is of a pointer type."
-    or
-    // Declaring an pointer variable to hold a integer value
-    var.getUnderlyingType() instanceof PointerType and
-    var.getAnAssignedValue().getUnderlyingType() instanceof IntType and
-    message =
-      "Pointer variable " + var + " is declared as an expression " + var.getAnAssignedValue() +
-        ", which is of integer type."
-  ) and
-  /* Compliant exception 1: literal 0 */
-  not var.getAnAssignedValue() instanceof LiteralZero and
-  /* Compliant exception 2: variable's declared type is (u)intptr_t */
-  not var.getUnderlyingType() instanceof StdIntIntPtrType
-}
+      exists(entry.getFile().(HeaderFile)) and
+      entry.getType() = this and
+      this.getName().regexpMatch("u?intptr_t")
+    )
+  }
 
-/* 2. Assigning an integer variable a pointer a pointer value, excluding literal 0 */
-predicate assigningPointerValueToInteger(Assignment assign, string message) {
-  (
-    assign.getLValue().getUnderlyingType() instanceof IntType and
-    assign.getRValue().getUnderlyingType() instanceof PointerType and
-    message =
-      "Integer variable " + assign.getLValue() + " is assigned an expression " + assign.getRValue() +
-        ", which is of a pointer type."
-    or
-    assign.getLValue().getUnderlyingType() instanceof PointerType and
-    assign.getRValue().getUnderlyingType() instanceof IntType and
-    message =
-      "Pointer variable " + assign.getLValue() + " is assigned an expression " + assign.getRValue() +
-        ", which is of integer type."
-  ) and
-  /* Compliant exception 1: literal 0 */
-  not assign.getRValue() instanceof LiteralZero and
-  /* Compliant exception 2: variable's declared type is (u)intptr_t */
-  not assign.getLValue().getUnderlyingType() instanceof StdIntIntPtrType
+  override string toString() {
+    if this.getName() = "uintptr_t" then result = "uintptr_t" else result = "intptr_t"
+  }
 }
 
-/* 3. Casting a pointer value to integer, excluding literal 0 */
-predicate castingPointerToInteger(Cast cast, string message) {
-  not cast.isCompilerGenerated() and
-  (
-    cast.getExpr().getUnderlyingType() instanceof IntType and
-    cast.getUnderlyingType() instanceof PointerType and
-    message = "Integer expression " + cast.getExpr() + " is cast to a pointer type."
+/**
+ * Casting a pointer value to integer, excluding literal 0.
+ * Includes implicit conversions made during declarations or assignments.
+ */
+predicate conversionBetweenPointerAndInteger(Cast cast, string message) {
+  /* Ensure that `int` has different size than that of pointers */
+  exists(IntType intType, PointerType ptrType | intType.getSize() < ptrType.getSize() |
+    cast.getExpr().getUnderlyingType() = intType and
+    cast.getUnderlyingType() = ptrType and
+    if cast.isCompilerGenerated()
+    then message = "Integer expression " + cast.getExpr() + " is implicitly cast to a pointer type."
+    else message = "Integer expression " + cast.getExpr() + " is cast to a pointer type."
     or
-    cast.getExpr().getUnderlyingType() instanceof PointerType and
-    cast.getUnderlyingType() instanceof IntType and
-    message = "Pointer expression " + cast.getExpr() + " is cast to integer type."
+    cast.getExpr().getUnderlyingType() = ptrType and
+    cast.getUnderlyingType() = intType and
+    if cast.isCompilerGenerated()
+    then
+      message = "Pointer expression " + cast.getExpr() + " is implicitly cast to an integer type."
+    else message = "Pointer expression " + cast.getExpr() + " is cast to an integer type."
   ) and
   /* Compliant exception 1: literal 0 */
   not cast.getExpr() instanceof LiteralZero and
   /* Compliant exception 2: variable's declared type is (u)intptr_t */
-  not cast.getUnderlyingType() instanceof StdIntIntPtrType
+  not (
+    cast.getType() instanceof StdIntIntPtrType and
+    cast.getExpr().getType() instanceof VoidPointerType
+    or
+    cast.getType() instanceof VoidPointerType and
+    cast.getExpr().getType() instanceof StdIntIntPtrType
+  )
 }
 
 from Element elem, string message
 where
   not isExcluded(elem, TypesPackage::convertingAPointerToIntegerOrIntegerToPointerQuery()) and
-  (
-    integerVariableWithPointerValue(elem, message)
-    or
-    assigningPointerValueToInteger(elem, message)
-    or
-    castingPointerToInteger(elem, message)
-  ) and
-  /* Ensure that `int` has different size than that of pointers */
-  forall(IntType intType, PointerType ptrType | intType.getSize() != ptrType.getSize())
+  conversionBetweenPointerAndInteger(elem, message)
 select elem, message