Fix FP for issue 216

exclude file stream call args
and heuristic wrappers

Author: knewbury01

change_notes/2023-03-16-fp-a5-1-1.md

@@ -0,0 +1 @@
+ * `A5-1-1` - reduce false positives by omitting literals written into file streams and wrappers around log and stream calls

cpp/autosar/src/rules/A5-1-1/LiteralValueUsedOutsideTypeInit.ql

@@ -18,6 +18,25 @@ import cpp
 import codingstandards.cpp.autosar
 import codingstandards.cpp.LoggingOperation
 import codingstandards.cpp.Literals
+import codingstandards.cpp.standardlibrary.FileStreams
+
+/**
+ * In a wrapper `Function`, all accesses of all `Parameters`
+ * are in located in logging or stream calls
+ */
+class LoggerOrStreamWrapperFunction extends Function {
+  LoggerOrStreamWrapperFunction() {
+    forall(Parameter p | p.getFunction() = this |
+      forall(VariableAccess va | va = p.getAnAccess() |
+        (
+          any(FileStreamFunctionCall fc).getAnArgument().getAChild*() = va
+          or
+          any(LoggingOperation logOp).getALoggedExpr().getAChild*() = va
+        )
+      )
+    )
+  }
+}
 
 from Literal l
 where
@@ -26,6 +45,11 @@ where
   not exists(ConstructorCall cc | cc.getAnArgument() = l) and
   not exists(ConstructorFieldInit cf | cf.getExpr() = l) and
   not l = any(LoggingOperation logOp).getALoggedExpr().getAChild*() and
+  not l = any(FileStreamFunctionCall fsc).getAnArgument().getAChild*() and
+  // Exclude arguments to wrapper functions
+  not exists(FunctionCall fc, LoggerOrStreamWrapperFunction w |
+    fc.getAnArgument() = l and w.getACallToThisFunction() = fc
+  ) and
   // Exclude literal 0
   not l.getValue() = "0" and
   // Exclude character literals

cpp/autosar/test/rules/A5-1-1/LiteralValueUsedOutsideTypeInit.expected

@@ -1,3 +1,5 @@
 | test.cpp:5:9:5:25 | constant string | Literal value "constant string" used outside of type initialization StringLiteral |
 | test.cpp:14:23:14:25 | 100 | Literal value 100 used outside of type initialization Literal |
 | test.cpp:54:7:54:7 | 1 | Literal value 1 used outside of type initialization Literal |
+| test.cpp:75:23:75:28 | test | Literal value "test" used outside of type initialization StringLiteral |
+| test.cpp:75:31:75:40 | not okay | Literal value "not okay" used outside of type initialization StringLiteral |

cpp/autosar/test/rules/A5-1-1/test.cpp

@@ -52,4 +52,26 @@ void test_class() {
 void test_assignment() {
   int x = 0; // COMPLIANT - used in type initialization
   x = 1;     // NON_COMPLIANT - used in assignment
-}
+}
+
+void test_stream(std::ostream &os, const char *str) noexcept {
+  os << str << "logging string"; // COMPLIANT - literal used in stream write
+}
+
+#define WRAPPER_MACRO(X, Y) test_stream(X, Y)
+
+void test_wrapper_stream(std::ostream &os, const char *str) noexcept {
+  test_stream(os, "test");   // COMPLIANT - wrapper for stream write
+  WRAPPER_MACRO(os, "test"); // COMPLIANT - wrapper for stream write
+}
+
+void test_stream_two(std::ostream &os, const char *str,
+                     const char *alt) noexcept {
+  os << str << "logging string"; // COMPLIANT - literal used in stream write
+  throw alt;
+}
+
+void test_not_wrapper_stream(std::ostream &os, const char *str) noexcept {
+  test_stream_two(os, "test", "not okay"); // NON_COMPLIANT - test_stream_two is
+                                           // not actually exclusively a wrapper
+}