Implement generics package

c/cert/src/rules/ARR39-C/DoNotAddOrSubtractAScaledIntegerToAPointer.ql

@@ -13,7 +13,7 @@
 
 import cpp
 import codingstandards.c.cert
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 import semmle.code.cpp.dataflow.TaintTracking
 import ScaledIntegerPointerArithmeticFlow::PathGraph
 

c/cert/src/rules/DCL40-C/IncompatibleFunctionDeclarations.ql

@@ -16,7 +16,7 @@
 
 import cpp
 import codingstandards.c.cert
-import codingstandards.cpp.Compatible
+import codingstandards.cpp.types.Compatible
 import ExternalIdentifiers
 
 from ExternalIdentifiers d, FunctionDeclarationEntry f1, FunctionDeclarationEntry f2
@@ -29,12 +29,10 @@ where
   f1.getName() = f2.getName() and
   (
     //return type check
-    not typesCompatible(f1.getType(), f2.getType())
+    not FunctionDeclarationTypeEquivalence<TypesCompatibleConfig>::equalReturnTypes(f1, f2)
     or
     //parameter type check
-    parameterTypesIncompatible(f1, f2)
-    or
-    not f1.getNumberOfParameters() = f2.getNumberOfParameters()
+    not FunctionDeclarationTypeEquivalence<TypesCompatibleConfig>::equalParameterTypes(f1, f2)
   ) and
   // Apply ordering on start line, trying to avoid the optimiser applying this join too early
   // in the pipeline

c/common/src/codingstandards/c/Generic.qll

@@ -0,0 +1,150 @@
+import cpp
+import codingstandards.cpp.Macro
+import codingstandards.cpp.MatchingParenthesis
+
+string genericRegexp() { result = "\\b_Generic\\s*\\(\\s*(.+),.*" }
+
+bindingset[input]
+string deparenthesize(string input) {
+  input = "(" + result + ")" and
+  result = input.substring(1, input.length() - 1)
+}
+
+class GenericMacro extends Macro {
+  string ctrlExpr;
+
+  GenericMacro() { ctrlExpr = getBody().regexpCapture(genericRegexp(), 1).trim() }
+
+  string getAParameter() { result = this.(FunctionLikeMacro).getAParameter() }
+
+  string getControllingExprString() {
+    if exists(string s | s = deparenthesize(ctrlExpr))
+    then result = deparenthesize(ctrlExpr).trim()
+    else result = ctrlExpr
+  }
+
+  /**
+   * Whether the controlling expression of the `_Generic` expr in this macro's controlling
+   * expression refers to one of this macro's parameters.
+   */
+  predicate hasControllingExprFromMacroParameter() {
+    getControllingExprString().matches(getAParameter())
+  }
+}
+
+class GenericMacroString extends string {
+  GenericMacroString() { this = any(Macro m).getBody() and this.matches("%_Generic%") }
+}
+
+import MatchingParenthesis<GenericMacroString>
+
+class ParsedGenericMacro extends Macro {
+  ParsedRoot macroBody;
+  Parsed genericBody;
+  string beforeGenericBody;
+  string afterGenericBody;
+
+  ParsedGenericMacro() {
+    macroBody.getInputString() = this.getBody() and
+    exists(ParsedText genericText |
+      genericText.getText().matches("%_Generic%") and
+      genericBody = genericText.getParent().getChild(genericText.getChildIdx() + 1) and
+      genericBody.getRoot() = macroBody
+    ) and
+    beforeGenericBody =
+      textFrom(macroBody.getStartToken(), genericBody.getStartToken().getPrevious()) and
+    (
+      if exists(genericBody.getEndToken().getNext())
+      then afterGenericBody = textFrom(genericBody.getEndToken().getNext(), macroBody.getEndToken())
+      else afterGenericBody = ""
+    )
+  }
+
+  string getAParameter() { result = this.(FunctionLikeMacro).getAParameter() }
+
+  int getAParsedGenericCommaSeparatorOffset() {
+    exists(ParsedText text |
+      text.getParent() = genericBody and
+      result = text.getStartToken().getStartPos() + text.getText().indexOf(",")
+    )
+  }
+
+  int getAParsedGenericColonSeparatorOffset() {
+    exists(ParsedText text |
+      text.getParent() = genericBody and
+      result = text.getStartToken().getStartPos() + text.getText().indexOf(":")
+    )
+  }
+
+  int getParsedGenericCommaSeparatorOffset(int i) {
+    result = rank[i](int index | index = getAParsedGenericCommaSeparatorOffset())
+  }
+
+  bindingset[start, end]
+  int getParsedGenericColon(int start, int end) {
+    result =
+      min(int offset |
+        offset = getAParsedGenericColonSeparatorOffset() and
+        offset >= start and
+        offset <= end
+      )
+  }
+
+  predicate hasParsedFullSelectionRange(int idx, int start, int end) {
+    idx = 1 and
+    start = genericBody.getStartToken().getEndPos() and
+    end = getParsedGenericCommaSeparatorOffset(idx)
+    or
+    not exists(getParsedGenericCommaSeparatorOffset(idx)) and
+    start = getParsedGenericCommaSeparatorOffset(idx - 1) and
+    end = genericBody.getEndToken().getStartPos()
+    or
+    start = getParsedGenericCommaSeparatorOffset(idx - 1) and
+    end = getParsedGenericCommaSeparatorOffset(idx)
+  }
+
+  string getSelectionString(int idx) {
+    exists(int start, int rawStart, int end |
+      hasParsedFullSelectionRange(idx, rawStart, end) and
+      (
+        if exists(getParsedGenericColon(rawStart, end))
+        then start = getParsedGenericColon(rawStart, end)
+        else start = rawStart
+      ) and
+      result = genericBody.getInputString().substring(start, end)
+    )
+  }
+
+  string getControllingExprString() { result = getSelectionString(1).trim() }
+
+  bindingset[str, word]
+  private int countWordInString(string word, string str) {
+    result =
+      max(int occurrence |
+        exists(str.regexpFind("\\b" + word + "\\b", occurrence, _)) or occurrence = -1
+      |
+        occurrence + 1
+      )
+  }
+
+  int expansionsOutsideExpr(string parameter) {
+    parameter = getAParameter() and
+    result =
+      countWordInString(parameter, beforeGenericBody) +
+        countWordInString(parameter, afterGenericBody)
+  }
+
+  int expansionsInsideSelection(string parameter, int idx) {
+    parameter = getAParameter() and
+    result = countWordInString(parameter, getSelectionString(idx))
+  }
+
+  int expansionsInsideControllingExpr(string parameter) {
+    result = expansionsInsideSelection(parameter, 1)
+  }
+
+  int expansionsInsideAssociation(string parameter, int idx) {
+    not idx = 0 and
+    result = expansionsInsideSelection(parameter, idx + 1)
+  }
+}

c/common/src/codingstandards/c/OutOfBounds.qll

@@ -5,7 +5,7 @@
  */
 
 import cpp
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 import codingstandards.c.Variable
 import codingstandards.cpp.Allocations
 import codingstandards.cpp.Overflow

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

@@ -1,5 +1,5 @@
 import cpp
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 import codingstandards.cpp.UndefinedBehavior
 
 /**

c/misra/src/codingstandards/c/misra/EssentialTypes.qll

@@ -164,14 +164,14 @@ EssentialTypeCategory getEssentialTypeCategory(Type type) {
  */
 pragma[nomagic]
 Type getEssentialType(Expr e) {
-  if e.hasExplicitConversion()
-  then
-    if e.getConversion() instanceof ParenthesisExpr
-    then
-      if e.getConversion().(ParenthesisExpr).hasExplicitConversion()
-      then result = e.getConversion().(ParenthesisExpr).getConversion().getType()
-      else result = e.getConversion().(ParenthesisExpr).getExpr().(EssentialExpr).getEssentialType()
-    else result = e.getConversion().getType()
+  if e.hasConversion()
+  then result = getEssentialTypeOfConversion(e.getFullyConverted())
+  else result = e.(EssentialExpr).getEssentialType()
+}
+
+Type getEssentialTypeOfConversion(Expr e) {
+  if e.(Conversion).isImplicit() or e instanceof ParenthesisExpr or e instanceof C11GenericExpr
+  then result = getEssentialTypeOfConversion(e.(Conversion).getExpr())
   else result = e.(EssentialExpr).getEssentialType()
 }
 
@@ -455,7 +455,7 @@ class EssentialLiteral extends EssentialExpr, Literal {
             if underlyingStandardType.(IntType).isSigned()
             then result = stlr(this)
             else result = utlr(this)
-          else result = underlyingStandardType
+          else result = getStandardType()
         )
     )
   }

c/misra/src/rules/RULE-11-1/ConversionBetweenFunctionPointerAndOtherType.ql

@@ -14,7 +14,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 from CStyleCast cast, Type type, Type newType
 where

c/misra/src/rules/RULE-11-2/ConversionBetweenIncompleteTypePointerAndOtherType.ql

@@ -14,7 +14,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 import codingstandards.cpp.Type
 
 from Cast cast, Type type, Type newType

c/misra/src/rules/RULE-11-3/CastBetweenObjectPointerAndDifferentObjectType.ql

@@ -15,7 +15,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 from CStyleCast cast, Type baseTypeFrom, Type baseTypeTo
 where

c/misra/src/rules/RULE-11-4/ConversionBetweenPointerToObjectAndIntegerType.ql

@@ -15,7 +15,7 @@
 import cpp
 import codingstandards.c.misra
 import codingstandards.cpp.Macro
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 MacroInvocation getAMacroInvocation(CStyleCast cast) { result.getAnExpandedElement() = cast }
 

c/misra/src/rules/RULE-11-5/ConversionFromPointerToVoidIntoPointerToObject.ql

@@ -14,7 +14,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 from Cast cast, VoidPointerType type, PointerToObjectType newType
 where

c/misra/src/rules/RULE-11-6/CastBetweenPointerToVoidAndArithmeticType.ql

@@ -14,7 +14,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 from CStyleCast cast, Type typeFrom, Type typeTo
 where

c/misra/src/rules/RULE-11-7/CastBetweenPointerToObjectAndNonIntArithmeticType.ql

@@ -14,7 +14,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 class MisraNonIntegerArithmeticType extends Type {
   MisraNonIntegerArithmeticType() {

c/misra/src/rules/RULE-11-9/MacroNullNotUsedAsIntegerNullPointerConstant.ql

@@ -13,7 +13,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 import codingstandards.cpp.Type
 
 from Zero zero, Expr e, string type

c/misra/src/rules/RULE-18-10/PointersToVariablyModifiedArrayTypesUsed.ql

@@ -16,7 +16,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.VariablyModifiedTypes
+import codingstandards.cpp.types.VariablyModifiedTypes
 
 from VmtDeclarationEntry v, string declstr, string adjuststr, string relationstr
 where

c/misra/src/rules/RULE-2-4/UnusedTagDeclaration.ql

@@ -15,7 +15,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.TypeUses
+import codingstandards.cpp.types.Uses
 
 from UserType s
 where

c/misra/src/rules/RULE-2-8/UnusedObjectDefinition.ql

@@ -20,5 +20,5 @@ from ReportDeadObject report
 where
   not isExcluded(report.getPrimaryElement(), DeadCode2Package::unusedObjectDefinitionQuery()) and
   not report.hasAttrUnused()
-select report.getPrimaryElement(), report.getMessage(), report.getOptionalPlaceholderLocation(),
+select report.getPrimaryElement(), report.getMessage(), report.getOptionalPlaceholderLocatable(),
   report.getOptionalPlaceholderMessage()

c/misra/src/rules/RULE-2-8/UnusedObjectDefinitionStrict.ql

@@ -22,5 +22,5 @@ from ReportDeadObject report
 where
   not isExcluded(report.getPrimaryElement(), DeadCode2Package::unusedObjectDefinitionStrictQuery()) and
   report.hasAttrUnused()
-select report.getPrimaryElement(), report.getMessage(), report.getOptionalPlaceholderLocation(),
+select report.getPrimaryElement(), report.getMessage(), report.getOptionalPlaceholderLocatable(),
   report.getOptionalPlaceholderMessage()

c/misra/src/rules/RULE-21-15/MemcpyMemmoveMemcmpArgNotPointersToCompatibleTypes.ql

@@ -13,7 +13,7 @@
 
 import cpp
 import codingstandards.c.misra
-import codingstandards.cpp.Pointers
+import codingstandards.cpp.types.Pointers
 
 class MemCmpMoveCpy extends Function {
   // Couldn't extend BuiltInFunction because it misses `memcmp`

c/misra/src/rules/RULE-23-1/GenericSelectionDoesntDependOnMacroArgument.ql

@@ -0,0 +1,27 @@
+/**
+ * @id c/misra/generic-selection-doesnt-depend-on-macro-argument
+ * @name RULE-23-1: A generic selection should depend on the type of a macro argument
+ * @description A generic selection should depend on the type of a macro argument.
+ * @kind problem
+ * @precision high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-23-1
+ *       correctness
+ *       maintainability
+ *       external/misra/c/2012/amendment3
+ *       external/misra/obligation/advisory
+ */
+
+import cpp
+import codingstandards.c.misra
+import codingstandards.c.Generic
+
+from ParsedGenericMacro macro, string ctrlExpr
+where
+  not isExcluded(macro, GenericsPackage::genericSelectionDoesntDependOnMacroArgumentQuery()) and
+  ctrlExpr = macro.getControllingExprString() and
+  // No parameter exists that is expanded in the controlling expression one or more times
+  not exists(string parameter | macro.expansionsInsideControllingExpr(parameter) > 0)
+select macro,
+  "Generic macro " + macro.getName() + " doesn't refer to a macro parameter in controlling expr '" +
+    ctrlExpr + "'."

c/misra/src/rules/RULE-23-1/GenericSelectionNotExpandedFromAMacro.ql

@@ -0,0 +1,23 @@
+/**
+ * @id c/misra/generic-selection-not-expanded-from-a-macro
+ * @name RULE-23-1: A generic selection should only be expanded from a macro
+ * @description A generic selection should only be expanded from a macro.
+ * @kind problem
+ * @precision very-high
+ * @problem.severity warning
+ * @tags external/misra/id/rule-23-1
+ *       maintainability
+ *       external/misra/c/2012/amendment3
+ *       external/misra/obligation/advisory
+ */
+
+import cpp
+import codingstandards.c.misra
+
+from C11GenericExpr generic, Expr ctrlExpr
+where
+  not isExcluded(generic, GenericsPackage::genericSelectionNotExpandedFromAMacroQuery()) and
+  ctrlExpr = generic.getControllingExpr() and
+  not exists(MacroInvocation mi | mi.getAGeneratedElement() = generic.getExpr())
+select generic, "$@ in generic expression does not expand a macro parameter.", ctrlExpr,
+  "Controlling expression"