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   nsresult rv;
  33   nsCOMPtr<nsIStorageStream> storageStream
  34     = do_CreateInstance("@mozilla.org/storagestream;1");
  35
  36   rv = storageStream->Init(256, PR_UINT32_MAX, nsnull);
  37   NS_ENSURE_SUCCESS(rv, rv);
  38
  39   nsCOMPtr<nsIObjectOutputStream> objectOutput
  40     = do_CreateInstance("@mozilla.org/binaryoutputstream;1");
  41   nsCOMPtr<nsIOutputStream> outputStream
  42     = do_QueryInterface(storageStream);
  43
  44   objectOutput->SetOutputStream(outputStream);
  45
  46 #ifdef DEBUG
  47   // Wrap in debug stream to detect unsupported writes of
  48   // multiply-referenced non-singleton objects
  49   StartupCache* sc = StartupCache::GetSingleton();
  50   NS_ENSURE_TRUE(sc, NS_ERROR_UNEXPECTED);
  51   nsCOMPtr<nsIObjectOutputStream> debugStream;
  52   sc->GetDebugObjectOutputStream(objectOutput, getter_AddRefs(debugStream));
  53   debugStream.forget(wrapperStream);
  54 #else
  55   objectOutput.forget(wrapperStream);
  56 #endif
  57
  58   storageStream.forget(stream);
  59   return NS_OK;
  60 }
  61
  62 NS_EXPORT nsresult
  63 NS_NewBufferFromStorageStream(nsIStorageStream *storageStream,
  64                               char** buffer, PRUint32* len)
  65 {
  66   nsresult rv;
  67   nsCOMPtr<nsIInputStream> inputStream;
  68   rv = storageStream->NewInputStream(0, getter_AddRefs(inputStream));
  69   NS_ENSURE_SUCCESS(rv, rv);
  70
  71   PRUint32 avail, read;
  72   rv = inputStream->Available(&avail);
  73   NS_ENSURE_SUCCESS(rv, rv);
  74
  75   nsAutoArrayPtr<char> temp (new char[avail]);
  76   rv = inputStream->Read(temp, avail, &read);
  77   if (NS_SUCCEEDED(rv) && avail != read)
  78     rv = NS_ERROR_UNEXPECTED;
  79
  80   if (NS_FAILED(rv)) {
  81     return rv;
  82   }
  83
  84   *len = avail;
  85   *buffer = temp.forget();
  86   return NS_OK;
  87 }
  88
  89 }
  90 }