--- /dev/null
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org
+ *
+ * The Initial Developer of the Original Code is
+ * Mozilla Foundation.
+ * Portions created by the Initial Developer are Copyright (C) 2010-2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ * Michael Wu <mwu@mozilla.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "mozJSLoaderUtils.h"
+#include "nsAutoPtr.h"
+
+#include "jsapi.h"
+#include "jsxdrapi.h"
+
+#include "mozilla/scache/StartupCache.h"
+#include "mozilla/scache/StartupCacheUtils.h"
+
+#include "nsIChromeRegistry.h"
+#include "nsIIOService.h"
+#include "nsIResProtocolHandler.h"
+#include "nsNetUtil.h"
+
+using namespace mozilla::scache;
+
+static nsresult
+ReadScriptFromStream(JSContext *cx, nsIObjectInputStream *stream,
+ JSScriptType **script)
+{
+ *script = nsnull;
+
+ PRUint32 size;
+ nsresult rv = stream->Read32(&size);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ char *data;
+ rv = stream->ReadBytes(size, &data);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ JSXDRState *xdr = JS_XDRNewMem(cx, JSXDR_DECODE);
+ NS_ENSURE_TRUE(xdr, NS_ERROR_OUT_OF_MEMORY);
+
+ xdr->userdata = stream;
+ JS_XDRMemSetData(xdr, data, size);
+
+ if (!JS_XDRScript(xdr, script)) {
+ rv = NS_ERROR_FAILURE;
+ }
+
+ // Update data in case ::JS_XDRScript called back into C++ code to
+ // read an XPCOM object.
+ //
+ // In that case, the serialization process must have flushed a run
+ // of counted bytes containing JS data at the point where the XPCOM
+ // object starts, after which an encoding C++ callback from the JS
+ // XDR code must have written the XPCOM object directly into the
+ // nsIObjectOutputStream.
+ //
+ // The deserialization process will XDR-decode counted bytes up to
+ // but not including the XPCOM object, then call back into C++ to
+ // read the object, then read more counted bytes and hand them off
+ // to the JSXDRState, so more JS data can be decoded.
+ //
+ // This interleaving of JS XDR data and XPCOM object data may occur
+ // several times beneath the call to ::JS_XDRScript, above. At the
+ // end of the day, we need to free (via nsMemory) the data owned by
+ // the JSXDRState. So we steal it back, nulling xdr's buffer so it
+ // doesn't get passed to ::JS_free by ::JS_XDRDestroy.
+
+ uint32 length;
+ data = static_cast<char*>(JS_XDRMemGetData(xdr, &length));
+ JS_XDRMemSetData(xdr, nsnull, 0);
+ JS_XDRDestroy(xdr);
+
+ // If data is null now, it must have been freed while deserializing an
+ // XPCOM object (e.g., a principal) beneath ::JS_XDRScript.
+ nsMemory::Free(data);
+
+ return rv;
+}
+
+static nsresult
+WriteScriptToStream(JSContext *cx, JSScriptType *script,
+ nsIObjectOutputStream *stream)
+{
+ JSXDRState *xdr = JS_XDRNewMem(cx, JSXDR_ENCODE);
+ NS_ENSURE_TRUE(xdr, NS_ERROR_OUT_OF_MEMORY);
+
+ xdr->userdata = stream;
+ nsresult rv = NS_OK;
+
+ if (JS_XDRScript(xdr, &script)) {
+ // Get the encoded JSXDRState data and write it. The JSXDRState owns
+ // this buffer memory and will free it beneath ::JS_XDRDestroy.
+ //
+ // If an XPCOM object needs to be written in the midst of the JS XDR
+ // encoding process, the C++ code called back from the JS engine (e.g.,
+ // nsEncodeJSPrincipals in caps/src/nsJSPrincipals.cpp) will flush data
+ // from the JSXDRState to aStream, then write the object, then return
+ // to JS XDR code with xdr reset so new JS data is encoded at the front
+ // of the xdr's data buffer.
+ //
+ // However many XPCOM objects are interleaved with JS XDR data in the
+ // stream, when control returns here from ::JS_XDRScript, we'll have
+ // one last buffer of data to write to aStream.
+
+ uint32 size;
+ const char* data = reinterpret_cast<const char*>
+ (JS_XDRMemGetData(xdr, &size));
+ NS_ASSERTION(data, "no decoded JSXDRState data!");
+
+ rv = stream->Write32(size);
+ if (NS_SUCCEEDED(rv)) {
+ rv = stream->WriteBytes(data, size);
+ }
+ } else {
+ rv = NS_ERROR_FAILURE; // likely to be a principals serialization error
+ }
+
+ JS_XDRDestroy(xdr);
+ return rv;
+}
+
+nsresult
+ReadCachedScript(nsIStartupCache* cache, nsACString &uri, JSContext *cx, JSScriptType **script)
+{
+ nsresult rv;
+
+ nsAutoArrayPtr<char> buf;
+ PRUint32 len;
+ rv = cache->GetBuffer(PromiseFlatCString(uri).get(), getter_Transfers(buf),
+ &len);
+ if (NS_FAILED(rv)) {
+ return rv; // don't warn since NOT_AVAILABLE is an ok error
+ }
+
+ nsCOMPtr<nsIObjectInputStream> ois;
+ rv = NewObjectInputStreamFromBuffer(buf, len, getter_AddRefs(ois));
+ NS_ENSURE_SUCCESS(rv, rv);
+ buf.forget();
+
+ return ReadScriptFromStream(cx, ois, script);
+}
+
+nsresult
+WriteCachedScript(nsIStartupCache* cache, nsACString &uri, JSContext *cx, JSScriptType *script)
+{
+ nsresult rv;
+
+ nsCOMPtr<nsIObjectOutputStream> oos;
+ nsCOMPtr<nsIStorageStream> storageStream;
+ rv = NewObjectOutputWrappedStorageStream(getter_AddRefs(oos),
+ getter_AddRefs(storageStream),
+ true);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = WriteScriptToStream(cx, script, oos);
+ oos->Close();
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ nsAutoArrayPtr<char> buf;
+ PRUint32 len;
+ rv = NewBufferFromStorageStream(storageStream, getter_Transfers(buf), &len);
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ rv = cache->PutBuffer(PromiseFlatCString(uri).get(), buf, len);
+ return rv;
+}
projects / dactyl.git / blobdiff