Bug 821726 - allow bypassing script cache when using loadSubscript, r=bholley

js/xpconnect/idl/mozIJSSubScriptLoader.idl

@@ -6,14 +6,14 @@
 
 #include "nsISupports.idl"
 
-[scriptable, uuid(837d0211-c448-4bb8-a9bf-922ba33b9d37)]
+[scriptable, uuid(b21f1579-d994-4e99-a85d-a685140f3ec1)]
 interface mozIJSSubScriptLoader : nsISupports
 {
     /**
      * This method should only be called from JS!
      * In JS, the signature looks like:
      * rv loadSubScript (url [, obj] [, charset]);
-     * @param url the url if the sub-script, it MUST be either a file:,
+     * @param url the url of the sub-script, it MUST be either a file:,
      *            resource:, or chrome: url, and MUST be local.
      * @param obj an optional object to evaluate the script onto, it
      *            defaults to the global object of the caller.
@@ -24,4 +24,19 @@ interface mozIJSSubScriptLoader : nsISupports
      */
     [implicit_jscontext]
     jsval loadSubScript(in AString url, [optional] in jsval obj, [optional] in AString charset);
+
+    /**
+     * This method should only be called from JS!
+     * In JS, the signature looks like:
+     * rv = loadSubScript (url, optionsObject)
+     * @param url the url of the sub-script, it MUST be either a file:,
+     *            resource:, or chrome: url, and MUST be local.
+     * @param optionsObject an object with parameters. Valid parameters are:
+     *                      - charset: specifying the character encoding of the file (default: ASCII)
+     *                      - target:  an object to evaluate onto (default: global object of the caller)
+     *                      - ignoreCache: if set to true, will bypass the cache for reading the file.
+     * @retval rv the value returned by the sub-script
+     */
+    [implicit_jscontext]
+    jsval loadSubScriptWithOptions(in AString url, in jsval options);
 };

js/xpconnect/loader/mozJSSubScriptLoader.cpp

@@ -24,12 +24,36 @@
 #include "js/OldDebugAPI.h"
 #include "nsJSPrincipals.h"
 #include "xpcpublic.h" // For xpc::SystemErrorReporter
+#include "xpcprivate.h" // For xpc::OptionsBase
 
 #include "mozilla/scache/StartupCache.h"
 #include "mozilla/scache/StartupCacheUtils.h"
 
 using namespace mozilla::scache;
 using namespace JS;
+using namespace xpc;
+
+class MOZ_STACK_CLASS LoadSubScriptOptions : public OptionsBase {
+public:
+    LoadSubScriptOptions(JSContext *cx = xpc_GetSafeJSContext(),
+                         JSObject *options = nullptr)
+        : OptionsBase(cx, options)
+        , target(cx)
+        , charset(NullString())
+        , ignoreCache(false)
+    { }
+
+    virtual bool Parse() {
+      return ParseObject("target", &target) &&
+             ParseString("charset", charset) &&
+             ParseBoolean("ignoreCache", &ignoreCache);
+    }
+
+    RootedObject target;
+    nsString charset;
+    bool ignoreCache;
+};
+
 
 /* load() error msgs, XXX localize? */
 #define LOAD_ERROR_NOSERVICE "Error creating IO Service."
@@ -172,10 +196,34 @@ mozJSSubScriptLoader::LoadSubScript(const nsAString& url,
      *        synchronously.
      *   target_obj: Optional object to eval the script onto (defaults to context
      *               global)
+     *   charset: Optional character set to use for reading
      *   returns: Whatever jsval the script pointed to by the url returns.
      * Should ONLY (O N L Y !) be called from JavaScript code.
      */
+    LoadSubScriptOptions options(cx);
+    options.charset = charset;
+    options.target = targetArg.isObject() ? &targetArg.toObject() : nullptr;
+    return DoLoadSubScriptWithOptions(url, options, cx, retval);
+}
 
+
+NS_IMETHODIMP
+mozJSSubScriptLoader::LoadSubScriptWithOptions(const nsAString& url, const Value& optionsVal,
+                                               JSContext* cx, Value* retval)
+{
+    if (!optionsVal.isObject())
+        return NS_ERROR_INVALID_ARG;
+    LoadSubScriptOptions options(cx, &optionsVal.toObject());
+    if (!options.Parse())
+        return NS_ERROR_INVALID_ARG;
+    return DoLoadSubScriptWithOptions(url, options, cx, retval);
+}
+
+nsresult
+mozJSSubScriptLoader::DoLoadSubScriptWithOptions(const nsAString& url,
+                                                 LoadSubScriptOptions& options,
+                                                 JSContext* cx, Value* retval)
+{
     nsresult rv = NS_OK;
 
     /* set the system principal if it's not here already */
@@ -195,17 +243,12 @@ mozJSSubScriptLoader::LoadSubScript(const nsAString& url,
     rv = loader->FindTargetObject(cx, &targetObj);
     NS_ENSURE_SUCCESS(rv, rv);
 
-    bool reusingGlobal = !JS_IsGlobalObject(targetObj);
-
     // We base reusingGlobal off of what the loader told us, but we may not
     // actually be using that object.
-    RootedValue target(cx, targetArg);
+    bool reusingGlobal = !JS_IsGlobalObject(targetObj);
-    RootedObject passedObj(cx);
-    if (!JS_ValueToObject(cx, target, &passedObj))
-        return NS_ERROR_ILLEGAL_VALUE;
 
-    if (passedObj)
+    if (options.target)
-        targetObj = passedObj;
+        targetObj = options.target;
 
     // Remember an object out of the calling compartment so that we
     // can properly wrap the result later.
@@ -292,10 +335,10 @@ mozJSSubScriptLoader::LoadSubScript(const nsAString& url,
 
     RootedFunction function(cx);
     script = nullptr;
-    if (cache)
+    if (cache && !options.ignoreCache)
         rv = ReadCachedScript(cache, cachePath, cx, mSystemPrincipal, &script);
     if (!script) {
-        rv = ReadScript(uri, cx, targetObj, charset,
+        rv = ReadScript(uri, cx, targetObj, options.charset,
                         static_cast<const char*>(uriStr.get()), serv,
                         principal, reusingGlobal, script.address(), function.address());
         writeScript = !!script;

js/xpconnect/loader/mozJSSubScriptLoader.h

@@ -9,6 +9,7 @@
 
 class nsIPrincipal;
 class nsIURI;
+class LoadSubScriptOptions;
 
 #define MOZ_JSSUBSCRIPTLOADER_CID                                             \
 { /* 829814d6-1dd2-11b2-8e08-82fa0a339b00 */                                  \
@@ -37,5 +38,9 @@ private:
                         bool reuseGlobal, JSScript **scriptp,
                         JSFunction **functionp);
 
+    nsresult DoLoadSubScriptWithOptions(const nsAString& url,
+                                        LoadSubScriptOptions& options,
+                                        JSContext* cx, JS::Value* retval);
+
     nsCOMPtr<nsIPrincipal> mSystemPrincipal;
 };

js/xpconnect/src/Sandbox.cpp

@@ -1277,7 +1277,7 @@ GetExpandedPrincipal(JSContext *cx, HandleObject arrayObj, nsIExpandedPrincipal
 }
 
 /*
- * Helper that tries to get a property form the options object.
+ * Helper that tries to get a property from the options object.
  */
 bool
 OptionsBase::ParseValue(const char *name, MutableHandleValue prop, bool *aFound)
@@ -1296,7 +1296,7 @@ OptionsBase::ParseValue(const char *name, MutableHandleValue prop, bool *aFound)
 }
 
 /*
- * Helper that tries to get a boolean property form the options object.
+ * Helper that tries to get a boolean property from the options object.
  */
 bool
 OptionsBase::ParseBoolean(const char *name, bool *prop)
@@ -1320,7 +1320,7 @@ OptionsBase::ParseBoolean(const char *name, bool *prop)
 }
 
 /*
- * Helper that tries to get an object property form the options object.
+ * Helper that tries to get an object property from the options object.
  */
 bool
 OptionsBase::ParseObject(const char *name, MutableHandleObject prop)
@@ -1342,7 +1342,7 @@ OptionsBase::ParseObject(const char *name, MutableHandleObject prop)
 }
 
 /*
- * Helper that tries to get a string property form the options object.
+ * Helper that tries to get a string property from the options object.
  */
 bool
 OptionsBase::ParseString(const char *name, nsCString &prop)
@@ -1367,7 +1367,32 @@ OptionsBase::ParseString(const char *name, nsCString &prop)
 }
 
 /*
- * Helper that tries to get jsid property form the options object.
+ * Helper that tries to get a string property from the options object.
+ */
+bool
+OptionsBase::ParseString(const char *name, nsString &prop)
+{
+    RootedValue value(mCx);
+    bool found;
+    bool ok = ParseValue(name, &value, &found);
+    NS_ENSURE_TRUE(ok, false);
+
+    if (!found)
+        return true;
+
+    if (!value.isString()) {
+        JS_ReportError(mCx, "Expected a string value for property %s", name);
+        return false;
+    }
+
+    nsDependentJSString strVal;
+    strVal.init(mCx, value.toString());
+    prop = strVal;
+    return true;
+}
+
+/*
+ * Helper that tries to get jsid property from the options object.
  */
 bool
 OptionsBase::ParseId(const char *name, MutableHandleId prop)

js/xpconnect/src/xpcprivate.h

@@ -3620,7 +3620,7 @@ IsSandbox(JSObject *obj);
 class MOZ_STACK_CLASS OptionsBase {
 public:
     OptionsBase(JSContext *cx = xpc_GetSafeJSContext(),
-                JS::HandleObject options = JS::NullPtr())
+                JSObject *options = nullptr)
         : mCx(cx)
         , mObject(cx, options)
     { }
@@ -3632,6 +3632,7 @@ protected:
     bool ParseBoolean(const char *name, bool *prop);
     bool ParseObject(const char *name, JS::MutableHandleObject prop);
     bool ParseString(const char *name, nsCString &prop);
+    bool ParseString(const char *name, nsString &prop);
     bool ParseId(const char* name, JS::MutableHandleId id);
 
     JSContext *mCx;
@@ -3641,7 +3642,7 @@ protected:
 class MOZ_STACK_CLASS SandboxOptions : public OptionsBase {
 public:
     SandboxOptions(JSContext *cx = xpc_GetSafeJSContext(),
-                   JS::HandleObject options = JS::NullPtr())
+                   JSObject *options = nullptr)
         : OptionsBase(cx, options)
         , wantXrays(true)
         , wantComponents(true)
@@ -3669,7 +3670,7 @@ protected:
 class MOZ_STACK_CLASS CreateObjectInOptions : public OptionsBase {
 public:
     CreateObjectInOptions(JSContext *cx = xpc_GetSafeJSContext(),
-                          JS::HandleObject options = JS::NullPtr())
+                          JSObject* options = nullptr)
         : OptionsBase(cx, options)
         , defineAs(cx, JSID_VOID)
     { }

js/xpconnect/tests/chrome/test_chrometoSource.xul

@@ -51,6 +51,12 @@ isnot(src.indexOf("return"), -1, "subscript of a subscript should have source");
 ns = {};
 Services.scriptloader.loadSubScript(resolvedBase + "utf8_subscript.js", ns, "UTF-8");
 src = ns.f.toSource();
+isnot(src.indexOf("return 42;"), -1, "encoded subscript should have correct source");
+
+ns = {};
+Services.scriptloader.loadSubScriptWithOptions(resolvedBase + "utf8_subscript.js",
+                                               {target: ns, charset: "UTF-8", ignoreCache: true});
+src = ns.f.toSource();
 isnot(src.indexOf("return 42;"), -1, "encoded subscript should have correct source");
   ]]></script>
 </window>