Bug 382034, support optional arguments in idl, r+sr=shaver

js/src/xpconnect/src/xpcwrappednative.cpp

@@ -1842,6 +1842,7 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
     nsIInterfaceInfo* ifaceInfo = ccx.GetInterface()->GetInterfaceInfo();
     jsval name = ccx.GetMember()->GetName();
     jsval* argv = ccx.GetArgv();
+    PRUint32 argc = ccx.GetArgc();
 
 #ifdef DEBUG_stats_jband
     PRIntervalTime startTime = PR_IntervalNow();
@@ -1904,10 +1905,16 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
     requiredArgs = paramCount;
     if(paramCount && methodInfo->GetParam(paramCount-1).IsRetval())
         requiredArgs--;
-    if(ccx.GetArgc() < requiredArgs)
+    if(argc < requiredArgs)
     {
-        Throw(NS_ERROR_XPC_NOT_ENOUGH_ARGS, ccx);
+        // skip over any optional arguments
-        goto done;
+        while (requiredArgs && methodInfo->GetParam(requiredArgs-1).IsOptional())
+          requiredArgs--;
+
+        if(argc < requiredArgs) {
+            Throw(NS_ERROR_XPC_NOT_ENOUGH_ARGS, ccx);
+            goto done;
+        }
     }
 
     // setup variant array pointer
@@ -1941,6 +1948,7 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
         const nsXPTParamInfo& paramInfo = methodInfo->GetParam(i);
         const nsXPTType& type = paramInfo.GetType();
         uint8 type_tag = type.TagPart();
+        jsval arg = paramInfo.IsOptional() && argc < i ? JSVAL_NULL : argv[i];
 
         if(type.IsDependent())
         {
@@ -1961,8 +1969,8 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
 
         if((paramInfo.IsOut() || paramInfo.IsDipper()) &&
            !paramInfo.IsRetval() &&
-           (JSVAL_IS_PRIMITIVE(argv[i]) ||
+           (JSVAL_IS_PRIMITIVE(arg) ||
-            !OBJ_GET_PROPERTY(ccx, JSVAL_TO_OBJECT(argv[i]),
+            !OBJ_GET_PROPERTY(ccx, JSVAL_TO_OBJECT(arg),
                               rt->GetStringID(XPCJSRuntime::IDX_VALUE),
                               &src)))
         {
@@ -2057,9 +2065,9 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
             }
 
             // Do this *after* the above because in the case where we have a
-            // "T_DOMSTRING && IsDipper()" then argv might be null since this
+            // "T_DOMSTRING && IsDipper()" then arg might be null since this
             // is really an 'out' param masquerading as an 'in' param.
-            src = argv[i];
+            src = arg;
         }
 
         if(type_tag == nsXPTType::T_INTERFACE &&
@@ -2085,6 +2093,7 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
         {
             const nsXPTParamInfo& paramInfo = methodInfo->GetParam(i);
             const nsXPTType& type = paramInfo.GetType();
+            jsval arg = paramInfo.IsOptional() && argc < i ? JSVAL_NULL : argv[i];
 
             if(!type.IsDependent())
                 continue;
@@ -2131,8 +2140,8 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
                 dp->ptr = &dp->val;
 
                 if(!paramInfo.IsRetval() &&
-                   (JSVAL_IS_PRIMITIVE(argv[i]) ||
+                   (JSVAL_IS_PRIMITIVE(arg) ||
-                    !OBJ_GET_PROPERTY(ccx, JSVAL_TO_OBJECT(argv[i]),
+                    !OBJ_GET_PROPERTY(ccx, JSVAL_TO_OBJECT(arg),
                         rt->GetStringID(XPCJSRuntime::IDX_VALUE), &src)))
                 {
                     ThrowBadParam(NS_ERROR_XPC_NEED_OUT_OBJECT, i, ccx);
@@ -2152,7 +2161,7 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
             }
             else
             {
-                src = argv[i];
+                src = arg;
 
                 if(datum_type.IsPointer() &&
                    datum_type.TagPart() == nsXPTType::T_IID)
@@ -2328,7 +2337,7 @@ XPCWrappedNative::CallMethod(XPCCallContext& ccx,
             if(!ccx.GetReturnValueWasSet())
                 ccx.SetRetVal(v);
         }
-        else
+        else if (!paramInfo.IsOptional() || argc > i)
         {
             // we actually assured this before doing the invoke
             NS_ASSERTION(JSVAL_IS_OBJECT(argv[i]), "out var is not object");

xpcom/reflect/xptinfo/public/xptinfo.h

@@ -159,6 +159,7 @@ public:
     PRBool IsRetval() const {return 0 != (XPT_PD_IS_RETVAL(flags));}
     PRBool IsShared() const {return 0 != (XPT_PD_IS_SHARED(flags));}
     PRBool IsDipper() const {return 0 != (XPT_PD_IS_DIPPER(flags));}
+    PRBool IsOptional() const {return 0 != (XPT_PD_IS_OPTIONAL(flags));}
     const nsXPTType GetType() const {return type.prefix;}
 
     // NOTE: other activities on types are done via methods on nsIInterfaceInfo

xpcom/typelib/xpidl/xpidl_typelib.c

@@ -988,6 +988,11 @@ fill_pd_from_param(TreeState *state, XPTParamDescriptor *pd, IDL_tree tree)
         flags |= XPT_PD_SHARED;
     }
 
+    if (IDL_tree_property_get(IDL_PARAM_DCL(tree).simple_declarator,
+                              "optional")) {
+        flags |= XPT_PD_OPTIONAL;
+    }
+
     /* stick param where we can see it later */
     state->tree = tree;
     return fill_pd_from_type(state, pd, flags,

xpcom/typelib/xpidl/xpidl_util.c

@@ -559,6 +559,7 @@ verify_method_declaration(IDL_tree method_tree)
     gboolean scriptable_interface;
     gboolean scriptable_method;
     gboolean seen_retval = FALSE;
+    gboolean hasoptional = PR_FALSE;
     const char *method_name = IDL_IDENT(IDL_OP_DCL(method_tree).ident).str;
 
     /* We don't support attributes named IID, conflicts with static GetIID 
@@ -716,6 +717,19 @@ verify_method_declaration(IDL_tree method_tree)
             }
         }
 
+        /*
+         * confirm that once an optional argument is used, all remaining
+         * arguments are marked as optional
+         */
+        if (IDL_tree_property_get(simple_decl, "optional") != NULL) {
+            hasoptional = PR_TRUE;
+        }
+        else if (hasoptional) {
+            IDL_tree_error(method_tree,
+                           "non-optional parameter used after one marked [optional]");
+                return FALSE;
+        }
+
         /*
          * inout is not allowed with "domstring", "UTF8String", "CString" 
          * and "AString" types

xpcom/typelib/xpt/public/xpt_struct.h

@@ -452,13 +452,15 @@ struct XPTParamDescriptor {
 #define XPT_PD_RETVAL   0x20
 #define XPT_PD_SHARED   0x10
 #define XPT_PD_DIPPER   0x08
-#define XPT_PD_FLAGMASK 0xf8
+#define XPT_PD_OPTIONAL 0x04
+#define XPT_PD_FLAGMASK 0xfc
 
 #define XPT_PD_IS_IN(flags)     (flags & XPT_PD_IN)
 #define XPT_PD_IS_OUT(flags)    (flags & XPT_PD_OUT)
 #define XPT_PD_IS_RETVAL(flags) (flags & XPT_PD_RETVAL)
 #define XPT_PD_IS_SHARED(flags) (flags & XPT_PD_SHARED)
 #define XPT_PD_IS_DIPPER(flags) (flags & XPT_PD_DIPPER)
+#define XPT_PD_IS_OPTIONAL(flags) (flags & XPT_PD_OPTIONAL)
 
 extern XPT_PUBLIC_API(PRBool)
 XPT_FillParamDescriptor(XPTArena *arena, 

xpcom/typelib/xpt/tools/xpt_dump.c

@@ -605,6 +605,9 @@ XPT_DumpMethodDescriptor(XPTHeader *header, XPTMethodDescriptor *md,
                         fprintf(stdout, "retval ");
                     }
                 }
+                if (XPT_PD_IS_OPTIONAL(pd->flags)) {
+                    fprintf(stdout, "optional ");
+                }
             } else {
                 if (XPT_PD_IS_OUT(pd->flags)) {
                     fprintf(stdout, "out ");
@@ -614,6 +617,9 @@ XPT_DumpMethodDescriptor(XPTHeader *header, XPTMethodDescriptor *md,
                     if (XPT_PD_IS_SHARED(pd->flags)) {
                         fprintf(stdout, "shared ");
                     }
+                    if (XPT_PD_IS_OPTIONAL(pd->flags)) {
+                        fprintf(stdout, "optional ");
+                    }
                 } else {
                     param_problems = PR_TRUE;
                     fprintf(stdout, "XXX ");
@@ -737,6 +743,12 @@ XPT_DumpParamDescriptor(XPTHeader *header, XPTParamDescriptor *pd,
     else 
         fprintf(stdout, "FALSE\n");
 
+    fprintf(stdout, "%*sOptional?     ", indent, " ");
+    if (XPT_PD_IS_OPTIONAL(pd->flags))
+        fprintf(stdout, "TRUE\n");
+    else 
+        fprintf(stdout, "FALSE\n");
+
 
     fprintf(stdout, "%*sType Descriptor:\n", indent, " ");
     if (!XPT_DumpTypeDescriptor(&pd->type, id, new_indent, verbose_mode))