1-3

Author: jsinglet

c/common/src/codingstandards/c/UndefinedBehavior.qll

@@ -0,0 +1,28 @@
+import cpp
+import codingstandards.cpp.UndefinedBehavior
+
+/**
+ * Library for modeling undefined behavior.
+ */
+abstract class CUndefinedBehavior extends UndefinedBehavior { }
+
+class C99MainFunction extends Function {
+  C99MainFunction() {
+    this.getNumberOfParameters() = 2 and
+    this.getType() instanceof IntType and
+    this.getParameter(0).getType() instanceof IntType and
+    this.getParameter(1).getType().(PointerType).getBaseType().(PointerType).getBaseType()
+      instanceof CharType
+    or
+    this.getNumberOfParameters() = 0 and
+    this.getType() instanceof VoidType
+  }
+}
+
+class CUndefinedMainDefinition extends CUndefinedBehavior, Function {
+  CUndefinedMainDefinition() {
+    // for testing purposes, we use the prefix ____codeql_coding_standards`
+    (this.getName() = "main" or this.getName().indexOf("____codeql_coding_standards") = 0) and
+    not this instanceof C99MainFunction
+  }
+}

c/misra/src/rules/RULE-1-3/OccurrenceOfUndefinedBehavior.ql

@@ -13,8 +13,8 @@
 
 import cpp
 import codingstandards.c.misra
+import codingstandards.c.UndefinedBehavior
 
-from
-where
-  not isExcluded(x, Language3Package::occurrenceOfUndefinedBehaviorQuery()) and
-select
+from CUndefinedBehavior c
+where not isExcluded(c, Language3Package::occurrenceOfUndefinedBehaviorQuery())
+select c, "May result in undefined behavior."

c/misra/test/rules/RULE-1-3/OccurrenceOfUndefinedBehavior.expected

@@ -1 +1,5 @@
-No expected results have yet been specified
+| test.c:8:6:8:35 | ____codeql_coding_standards_m2 | May result in undefined behavior. |
+| test.c:11:5:11:34 | ____codeql_coding_standards_m3 | May result in undefined behavior. |
+| test.c:15:5:15:34 | ____codeql_coding_standards_m4 | May result in undefined behavior. |
+| test.c:19:5:19:34 | ____codeql_coding_standards_m5 | May result in undefined behavior. |
+| test.c:23:5:23:34 | ____codeql_coding_standards_m6 | May result in undefined behavior. |

c/misra/test/rules/RULE-1-3/test.c

@@ -0,0 +1,25 @@
+void main(void) { // COMPLIANT
+}
+
+int ____codeql_coding_standards_m1(int argc, char **argv) { // NON_COMPLIANT
+  return 0;
+}
+
+void ____codeql_coding_standards_m2(char *argc, char **argv) { // NON_COMPLIANT
+}
+
+int ____codeql_coding_standards_m3(int argc, char *argv) { // NON_COMPLIANT
+  return 0;
+}
+
+int ____codeql_coding_standards_m4() { // NON_COMPLIANT
+  return 0;
+}
+
+int ____codeql_coding_standards_m5(int argc, int *argv) { // NON_COMPLIANT
+  return 0;
+}
+
+int ____codeql_coding_standards_m6(int argc, int **argv) { // NON_COMPLIANT
+  return 0;
+}

cpp/common/src/codingstandards/cpp/UndefinedBehavior.qll

@@ -0,0 +1,6 @@
+import cpp 
+/**
+ * Library for modeling undefined behavior.
+ */
+abstract class UndefinedBehavior extends Locatable {}
+abstract class CPPUndefinedBehavior extends UndefinedBehavior {}

rule_packages/c/Language3.json

@@ -38,7 +38,10 @@
           "tags": [
             "maintainability",
             "readability" 
-          ]
+          ],
+          "implementation_scope": {
+            "description": "This implementation only considers alternate forms of `main` and the undefined behavior that results. Additional cases from Appendix J of the C99 standard are not currently considered."
+          }
         }
       ],
       "title": "There shall be no occurrence of undefined or critical unspecified behavior"