/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

/* vim: set ts=8 sts=4 et sw=4 tw=99: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/scache/StartupCache.h"

#include "jsapi.h"

#include "jsfriendapi.h"

#include "nsJSPrincipals.h"

using namespace JS;

using namespace mozilla::scache;

using mozilla::UniquePtr;

// We only serialize scripts with system principals. So we don't serialize the

// principals when writing a script. Instead, when reading it back, we set the

// principals to the system principals.

nsresult

ReadCachedScript(StartupCache* cache, nsACString& uri, JSContext* cx,

                 MutableHandleScript scriptp)

{

    UniquePtr<char[]> buf;

    uint32_t len;

    nsresult rv = cache->GetBuffer(PromiseFlatCString(uri).get(), &buf, &len);

    if (NS_FAILED(rv)) {

        return rv; // don't warn since NOT_AVAILABLE is an ok error

    }

    JS::TranscodeBuffer buffer;

    buffer.replaceRawBuffer(reinterpret_cast<uint8_t*>(buf.release()), len);

    JS::TranscodeResult code = JS::DecodeScript(cx, buffer, scriptp);

    if (code == JS::TranscodeResult_Ok) {

        return NS_OK;

    }

    if ((code & JS::TranscodeResult_Failure) != 0) {

        return NS_ERROR_FAILURE;

    }

    MOZ_ASSERT((code & JS::TranscodeResult_Throw) != 0);

    JS_ClearPendingException(cx);

    return NS_ERROR_OUT_OF_MEMORY;

}

nsresult

WriteCachedScript(StartupCache* cache, nsACString& uri, JSContext* cx,

                  HandleScript script)

{

    MOZ_ASSERT(nsJSPrincipals::get(JS_GetScriptPrincipals(script))->GetIsSystemPrincipal());

    JS::TranscodeBuffer buffer;

    JS::TranscodeResult code = JS::EncodeScript(cx, buffer, script);

    if (code != JS::TranscodeResult_Ok) {

        if ((code & JS::TranscodeResult_Failure) != 0) {

            return NS_ERROR_FAILURE;

        }

        MOZ_ASSERT((code & JS::TranscodeResult_Throw) != 0);

        JS_ClearPendingException(cx);

        return NS_ERROR_OUT_OF_MEMORY;

    }

    size_t size = buffer.length();

    if (size > UINT32_MAX) {

        return NS_ERROR_FAILURE;

    }

    // Move the vector buffer into a unique pointer buffer.

    UniquePtr<char[]> buf(reinterpret_cast<char*>(buffer.extractOrCopyRawBuffer()));

    nsresult rv = cache->PutBuffer(PromiseFlatCString(uri).get(),

                                   std::move(buf),

                                   size);

    return rv;

}