FIO-46: file as expression

Author: mbaluda

cpp/common/src/codingstandards/cpp/rules/donotaccessaclosedfile/DoNotAccessAClosedFile.qll

@@ -27,7 +27,7 @@ predicate accessSameVariable(VariableAccess va1, VariableAccess va2) {
   va1.getTarget() = va2.getTarget()
 }
 
-SubBasicBlock followsFileClose(SubBasicBlock source, VariableAccess closedFile) {
+SubBasicBlock followsFileClose(SubBasicBlock source, Expr closedFile) {
   result = source
   or
   exists(SubBasicBlock mid |

cpp/common/src/codingstandards/cpp/standardlibrary/FileAccess.qll

@@ -114,18 +114,18 @@ class ImplicitFileAccess extends FileAccess {
   string fileName;
 
   ImplicitFileAccess() {
-    fileName = ["stdin", "_Stdin"] and
+    fileName = "stdin" and
     this.getTarget().hasGlobalName(["getchar", "getwchar", "scanf", "scanf_s"])
     or
-    fileName = ["stdout", "_Stdout"] and
+    fileName = "stdout" and
     this.getTarget().hasGlobalName(["printf", "printf_s", "puts", "putchar", "putwchar"])
     or
-    fileName = ["stderr", "_Stderr"] and this.getTarget().hasGlobalName("perror")
+    fileName = "stderr" and this.getTarget().hasGlobalName("perror")
   }
 
   /** The expression corresponding to the accessed file */
   override Expr getFileExpr() {
-    fileName = result.(VariableAccess).getTarget().(GlobalVariable).toString() or
+    result = any(MacroInvocation mi | mi.getMacroName() = fileName).getExpr() or
     fileName = result.findRootCause().(Macro).getName()
   }
 }