startupcache/nsStartupCacheUtils.cpp

   1 /* -*-  Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is Startup Cache.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * The Mozilla Foundation <http://www.mozilla.org/>.
  19  * Portions created by the Initial Developer are Copyright (C) 2009
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *  Benedict Hsieh <bhsieh@mozilla.com>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
  27  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
  30  * under the terms of either the GPL or the LGPL, and not to allow others to
  31  * use your version of this file under the terms of the MPL, indicate your
  32  * decision by deleting the provisions above and replace them with the notice
  33  * and other provisions required by the GPL or the LGPL. If you do not delete
  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "nsStartupCacheUtils.h"
  40
  41 #include "nsCOMPtr.h"
  42 #include "nsComponentManagerUtils.h"
  43 #include "nsIInputStream.h"
  44 #include "nsIStorageStream.h"
  45 #include "nsIStringStream.h"
  46 #include "nsIObjectInputStream.h"
  47 #include "nsIObjectOutputStream.h"
  48
  49 nsresult
  50 NS_NewObjectInputStreamFromBuffer(char* buffer, int len,
  51                                   nsIObjectInputStream** stream)
  52 {
  53   nsCOMPtr<nsIStringInputStream> stringStream
  54     = do_CreateInstance("@mozilla.org/io/string-input-stream;1");
  55   if (!stringStream)
  56     return NS_ERROR_OUT_OF_MEMORY;
  57   nsCOMPtr<nsIObjectInputStream> objectInput
  58     = do_CreateInstance("@mozilla.org/binaryinputstream;1");
  59   if (!objectInput)
  60     return NS_ERROR_OUT_OF_MEMORY;
  61
  62   stringStream->AdoptData(buffer, len);
  63   objectInput->SetInputStream(stringStream);
  64
  65   NS_ADDREF(*stream = objectInput);
  66   return NS_OK;
  67 }
  68
  69 // This is questionable API name and design, but we can't
  70 // retrieve the wrapped stream from the objectOutputStream later...
  71 nsresult
  72 NS_NewObjectOutputWrappedStorageStream(nsIObjectOutputStream **wrapperStream,
  73                                        nsIStorageStream** stream)
  74 {
  75   nsCOMPtr<nsIStorageStream> storageStream;
  76   nsresult rv = NS_NewStorageStream(256, (PRUint32)-1,
  77                                     getter_AddRefs(storageStream));
  78   NS_ENSURE_SUCCESS(rv, rv);
  79
  80   nsCOMPtr<nsIObjectOutputStream> objectOutput
  81     = do_CreateInstance("@mozilla.org/binaryoutputstream;1");
  82   if (!objectOutput)
  83     return NS_ERROR_OUT_OF_MEMORY;
  84
  85   nsCOMPtr<nsIOutputStream> outputStream
  86     = do_QueryInterface(storageStream);
  87
  88   objectOutput->SetOutputStream(outputStream);
  89   NS_ADDREF(*wrapperStream = objectOutput);
  90   NS_ADDREF(*stream = storageStream);
  91   return NS_OK;
  92 }
  93
  94 nsresult
  95 NS_NewBufferFromStorageStream(nsIStorageStream *storageStream,
  96                               char** buffer, int* len)
  97 {
  98   nsresult rv;
  99   nsCOMPtr<nsIInputStream> inputStream;
 100   rv = storageStream->NewInputStream(0, getter_AddRefs(inputStream));
 101   NS_ENSURE_SUCCESS(rv, rv);
 102
 103   PRUint32 avail, read;
 104   rv = inputStream->Available(&avail);
 105   NS_ENSURE_SUCCESS(rv, rv);
 106
 107   char* temp = new char[avail];
 108   if (!temp)
 109     return NS_ERROR_OUT_OF_MEMORY;
 110
 111   rv = inputStream->Read(temp, avail, &read);
 112   if (NS_SUCCEEDED(rv) && avail != read)
 113     rv = NS_ERROR_UNEXPECTED;
 114
 115   if (NS_FAILED(rv)) {
 116     delete temp;
 117     return rv;
 118   }
 119
 120   *len = avail;
 121   *buffer = temp;
 122   return NS_OK;
 123 }
 124