consider increment operator

Author: mbaluda

c/cert/src/rules/ENV30-C/DoNotModifyTheReturnValueOfCertainFunctions.ql

@@ -45,6 +45,8 @@ Expr objectModified(NotModifiableCall c) {
       ae.getRValue().(FunctionCall).getArgument(0).getValue() = ["0", "3", "4"]
     )
   )
+  or
+  exists(CrementOperation co | result = co.getOperand())
 }
 
 /**

c/cert/test/rules/ENV30-C/DoNotModifyTheReturnValueOfCertainFunctions.expected

@@ -74,4 +74,5 @@ subpaths
 | test.c:21:9:21:12 | env1 | test.c:5:18:5:22 | c_str | test.c:5:18:5:22 | c_str | test.c:21:9:21:12 | ref arg env1 |
 #select
 | test.c:8:7:8:12 | * ... | test.c:15:16:15:21 | call to getenv | test.c:8:7:8:12 | * ... | The object returned by the function getenv should no be modified. |
+| test.c:10:7:10:11 | c_str | test.c:15:16:15:21 | call to getenv | test.c:10:7:10:11 | c_str | The object returned by the function getenv should no be modified. |
 | test.c:63:5:63:9 | conv4 | test.c:60:11:60:19 | call to setlocale | test.c:63:5:63:9 | conv4 | The object returned by the function setlocale should no be modified. |

c/cert/test/rules/ENV30-C/test.c

@@ -5,9 +5,9 @@
 void trstr(char *c_str, char orig, char rep) {
   while (*c_str != '\0') {
     if (*c_str == orig) {
-      *c_str = rep;
+      *c_str = rep; // NON_COMPLIANT
     }
-    ++c_str;
+    ++c_str; // NON_COMPLIANT
   }
 }
 
@@ -18,7 +18,7 @@ void f1(void) {
 
   if (env1 == NULL) {
   }
-  trstr(env1, '"', '_'); // NON_COMPLIANT
+  trstr(env1, '"', '_');
 }
 
 void f2(void) {