C++: Factored the body of TooManyArguments.ql out into a library file

cpp/ql/src/Likely Bugs/Underspecified Functions/TooManyArguments.ql

@@ -12,35 +12,8 @@
  */
 
 import cpp
-
-// True if function was ()-declared, but not (void)-declared or K&R-defined
-// or implicitly declared (i.e., lacking a prototype)
-predicate hasZeroParamDecl(Function f) {
-  exists(FunctionDeclarationEntry fde | fde = f.getADeclarationEntry() |
-    not fde.isImplicit() and
-    not fde.hasVoidParamList() and
-    fde.getNumberOfParameters() = 0 and
-    not fde.isDefinition()
-  )
-}
-
-// True if this file (or header) was compiled as a C file
-predicate isCompiledAsC(File f) {
-  f.compiledAsC()
-  or
-  exists(File src | isCompiledAsC(src) | src.getAnIncludedFile() = f)
-}
+import TooManyArguments
 
 from FunctionCall fc, Function f
-where
-  f = fc.getTarget() and
-  not f.isVarargs() and
-  hasZeroParamDecl(f) and
-  isCompiledAsC(f.getFile()) and
-  exists(f.getBlock()) and
-  // There must not exist a declaration with the number of parameters
-  // at least as large as the number of call arguments
-  not exists(FunctionDeclarationEntry fde | fde = f.getADeclarationEntry() |
-    fde.getNumberOfParameters() >= fc.getNumberOfArguments()
-  )
+where tooManyArguments(fc, f)
 select fc, "This call has more arguments than required by $@.", f, f.toString()

cpp/ql/src/Likely Bugs/Underspecified Functions/TooManyArguments.qll

@@ -0,0 +1,38 @@
+/**
+ * Provides the implementation of the TooManyArguments query. The
+ * query is implemented as a library, so that we can avoid producing
+ * duplicate results in other similar queries.
+ */
+
+import cpp
+
+// True if function was ()-declared, but not (void)-declared or K&R-defined
+// or implicitly declared (i.e., lacking a prototype)
+private predicate hasZeroParamDecl(Function f) {
+  exists(FunctionDeclarationEntry fde | fde = f.getADeclarationEntry() |
+    not fde.isImplicit() and
+    not fde.hasVoidParamList() and
+    fde.getNumberOfParameters() = 0 and
+    not fde.isDefinition()
+  )
+}
+
+// True if this file (or header) was compiled as a C file
+private predicate isCompiledAsC(File f) {
+  f.compiledAsC()
+  or
+  exists(File src | isCompiledAsC(src) | src.getAnIncludedFile() = f)
+}
+
+predicate tooManyArguments(FunctionCall fc, Function f) {
+  f = fc.getTarget() and
+  not f.isVarargs() and
+  hasZeroParamDecl(f) and
+  isCompiledAsC(f.getFile()) and
+  exists(f.getBlock()) and
+  // There must not exist a declaration with the number of parameters
+  // at least as large as the number of call arguments
+  not exists(FunctionDeclarationEntry fde | fde = f.getADeclarationEntry() |
+    fde.getNumberOfParameters() >= fc.getNumberOfArguments()
+  )
+}