startupcache/StartupCacheUtils.cpp

   1
   2 #include "nsCOMPtr.h"
   3 #include "nsIInputStream.h"
   4 #include "nsIStringStream.h"
   5 #include "nsAutoPtr.h"
   6 #include "StartupCacheUtils.h"
   7 #include "mozilla/scache/StartupCache.h"
   8
   9 namespace mozilla {
  10 namespace scache {
  11
  12 NS_EXPORT nsresult
  13 NS_NewObjectInputStreamFromBuffer(char* buffer, PRUint32 len,
  14                                   nsIObjectInputStream** stream)
  15 {
  16   nsCOMPtr<nsIStringInputStream> stringStream
  17     = do_CreateInstance("@mozilla.org/io/string-input-stream;1");
  18   nsCOMPtr<nsIObjectInputStream> objectInput
  19     = do_CreateInstance("@mozilla.org/binaryinputstream;1");
  20
  21   stringStream->AdoptData(buffer, len);
  22   objectInput->SetInputStream(stringStream);
  23
  24   objectInput.forget(stream);
  25   return NS_OK;
  26 }
  27
  28 NS_EXPORT nsresult
  29 NS_NewObjectOutputWrappedStorageStream(nsIObjectOutputStream **wrapperStream,
  30                                        nsIStorageStream** stream)
  31 {
  32   nsCOMPtr<nsIStorageStream> storageStream;
  33
  34   nsresult rv = NS_NewStorageStream(256, PR_UINT32_MAX, getter_AddRefs(storageStream));
  35   NS_ENSURE_SUCCESS(rv, rv);
  36
  37   nsCOMPtr<nsIObjectOutputStream> objectOutput
  38     = do_CreateInstance("@mozilla.org/binaryoutputstream;1");
  39   nsCOMPtr<nsIOutputStream> outputStream
  40     = do_QueryInterface(storageStream);
  41
  42   objectOutput->SetOutputStream(outputStream);
  43
  44 #ifdef DEBUG
  45   // Wrap in debug stream to detect unsupported writes of
  46   // multiply-referenced non-singleton objects
  47   StartupCache* sc = StartupCache::GetSingleton();
  48   NS_ENSURE_TRUE(sc, NS_ERROR_UNEXPECTED);
  49   nsCOMPtr<nsIObjectOutputStream> debugStream;
  50   sc->GetDebugObjectOutputStream(objectOutput, getter_AddRefs(debugStream));
  51   debugStream.forget(wrapperStream);
  52 #else
  53   objectOutput.forget(wrapperStream);
  54 #endif
  55
  56   storageStream.forget(stream);
  57   return NS_OK;
  58 }
  59
  60 NS_EXPORT nsresult
  61 NS_NewBufferFromStorageStream(nsIStorageStream *storageStream,
  62                               char** buffer, PRUint32* len)
  63 {
  64   nsresult rv;
  65   nsCOMPtr<nsIInputStream> inputStream;
  66   rv = storageStream->NewInputStream(0, getter_AddRefs(inputStream));
  67   NS_ENSURE_SUCCESS(rv, rv);
  68
  69   PRUint32 avail, read;
  70   rv = inputStream->Available(&avail);
  71   NS_ENSURE_SUCCESS(rv, rv);
  72
  73   nsAutoArrayPtr<char> temp (new char[avail]);
  74   rv = inputStream->Read(temp, avail, &read);
  75   if (NS_SUCCEEDED(rv) && avail != read)
  76     rv = NS_ERROR_UNEXPECTED;
  77
  78   if (NS_FAILED(rv)) {
  79     return rv;
  80   }
  81
  82   *len = avail;
  83   *buffer = temp.forget();
  84   return NS_OK;
  85 }
  86
  87 }
  88 }