xpcom/io/StreamBufferSource.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   5  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_StreamBufferSource_h
   8 #define mozilla_StreamBufferSource_h
   9
  10 #include <cstddef>
  11 #include "ErrorList.h"
  12 #include "mozilla/MemoryReporting.h"
  13 #include "mozilla/Span.h"
  14 #include "nsISupportsImpl.h"
  15 #include "nsString.h"
  16
  17 namespace mozilla {
  18
  19 class StreamBufferSource {
  20  public:
  21   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(StreamBufferSource)
  22
  23   virtual Span<const char> Data() = 0;
  24
  25   virtual nsresult GetData(nsACString& aString) {
  26     Span<const char> data = Data();
  27     if (!aString.Assign(data.Elements(), data.Length(), fallible)) {
  28       return NS_ERROR_OUT_OF_MEMORY;
  29     }
  30     return NS_OK;
  31   }
  32
  33   virtual bool Owning() = 0;
  34
  35   virtual size_t SizeOfExcludingThisIfUnshared(MallocSizeOf aMallocSizeOf) {
  36     return SizeOfExcludingThisEvenIfShared(aMallocSizeOf);
  37   }
  38   size_t SizeOfIncludingThisIfUnshared(MallocSizeOf aMallocSizeOf) {
  39     if (mRefCnt > 1) {
  40       return 0;
  41     }
  42     size_t n = aMallocSizeOf(this);
  43     n += SizeOfExcludingThisIfUnshared(aMallocSizeOf);
  44     return n;
  45   }
  46
  47   virtual size_t SizeOfExcludingThisEvenIfShared(
  48       MallocSizeOf aMallocSizeOf) = 0;
  49   size_t SizeOfIncludingThisEvenIfShared(MallocSizeOf aMallocSizeOf) {
  50     size_t n = aMallocSizeOf(this);
  51     n += SizeOfExcludingThisEvenIfShared(aMallocSizeOf);
  52     return n;
  53   }
  54
  55  protected:
  56   virtual ~StreamBufferSource() = default;
  57 };
  58
  59 }  // namespace mozilla
  60
  61 #endif  // mozilla_StreamBufferSource_h