From d181e98d02f4b983d9bcbbc3312188043ab7f085 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Mon, 16 Apr 2018 13:55:12 +0200
Subject: [PATCH] misc.py: Added experimental ellipsisStructArg checker that
 warns when struct is passed to ellipsis function

---
 addons/misc.py            | 44 ++++++++++++++++++++++++++++++++++++++-
 addons/test/misc-test.cpp | 14 ++++++++++++-
 2 files changed, 56 insertions(+), 2 deletions(-)

diff --git a/addons/misc.py b/addons/misc.py
index ffabd2375..06cb3aae3 100644
--- a/addons/misc.py
+++ b/addons/misc.py
@@ -28,6 +28,21 @@ def simpleMatch(token, pattern):
         token = token.next
     return True
 
+# Get function arguments
+def getArgumentsRecursive(tok, arguments):
+    if tok is None:
+        return
+    if tok.str == ',':
+        getArgumentsRecursive(tok.astOperand1, arguments)
+        getArgumentsRecursive(tok.astOperand2, arguments)
+    else:
+        arguments.append(tok);
+
+def getArguments(ftok):
+    arguments = []
+    getArgumentsRecursive(ftok.astOperand2, arguments)
+    return arguments
+
 def isStringLiteral(tokenString):
     return tokenString.startswith('"')
 
@@ -64,6 +79,32 @@ def implicitlyVirtual(data):
                 continue
             reportError(function.tokenDef, 'style', 'Function \'' + function.name + '\' overrides base class function but is not marked with \'virtual\' keyword.', 'implicitlyVirtual')
 
+def ellipsisStructArg(data):
+    for cfg in data.configurations:
+        for tok in cfg.tokenlist:
+            if tok.str != '(':
+                continue
+            if tok.astOperand1 is None or tok.astOperand2 is None:
+                continue
+            if tok.astOperand1.function is None:
+                continue
+            for argnr, argvar in tok.astOperand1.function.argument.items():
+                if argnr < 1:
+                    continue
+                if not simpleMatch(argvar.typeStartToken, '. . .'):
+                    continue
+                callArgs = getArguments(tok)
+                for i in range(argnr-1, len(callArgs)):
+                    valueType = callArgs[i].valueType
+                    if not valueType:
+                        continue
+                    if valueType.pointer > 0:
+                        continue
+                    if valueType.type != 'record':
+                        continue
+                    reportError(tok, 'style', 'Passing record to ellipsis function \'' + tok.astOperand1.function.name + '\'.', 'ellipsisStructArg')
+                break
+
 for arg in sys.argv[1:]:
     if arg == '-verify':
         continue
@@ -76,11 +117,12 @@ for arg in sys.argv[1:]:
         for tok in data.rawTokens:
             if tok.str.startswith('//'):
                 for word in tok.str[2:].split(' '):
-                    if word == 'stringConcatInArrayInit' or word == 'implicitlyVirtual':
+                    if word in ['stringConcatInArrayInit', 'implicitlyVirtual', 'ellipsisStructArg']:
                         VERIFY_EXPECTED.append(str(tok.linenr) + ':' + word)
 
     stringConcatInArrayInit(data.rawTokens)
     implicitlyVirtual(data)
+    ellipsisStructArg(data)
 
     if VERIFY:
         for expected in VERIFY_EXPECTED:
diff --git a/addons/test/misc-test.cpp b/addons/test/misc-test.cpp
index 8029262ae..c2d1b1206 100644
--- a/addons/test/misc-test.cpp
+++ b/addons/test/misc-test.cpp
@@ -1,6 +1,8 @@
 // To test:
-// ~/cppcheck/cppcheck --dump misc-test.c && python ../misc.py -verify misc-test.c.dump
+// ~/cppcheck/cppcheck --dump misc-test.cpp && python ../misc.py -verify misc-test.cpp.dump
 
+
+// Warn about string concatenation in array initializers..
 const char *a[] = {"a" "b"};
 const char *b[] = {"a","b" "c"}; // stringConcatInArrayInit
 const char *c[] = {
@@ -17,6 +19,8 @@ const char *c[] = {
 	"b\n"
 };
 
+
+// Function is implicitly virtual
 class base {
     virtual void dostuff(int);	
 };
@@ -24,3 +28,11 @@ class base {
 class derived : base {
 	void dostuff(int); // implicitlyVirtual
 };
+
+
+// Pass struct to ellipsis function
+struct {int x;int y;} s;
+void ellipsis(int x, ...);
+void foo(void) {
+    ellipsis(321, s); // ellipsisStructArg
+}