DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (d96ee8115c5a)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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 "FileMediaResource.h"

#include "nsContentUtils.h"
#include "nsHostObjectProtocolHandler.h"
#include "nsIFileChannel.h"
#include "nsIFileStreams.h"
#include "nsNetUtil.h"

namespace mozilla {

void FileMediaResource::EnsureSizeInitialized() {
  mLock.AssertCurrentThreadOwns();
  NS_ASSERTION(mInput, "Must have file input stream");
  if (mSizeInitialized && mNotifyDataEndedProcessed) {
    return;
  }

  if (!mSizeInitialized) {
    // Get the file size and inform the decoder.
    uint64_t size;
    nsresult res = mInput->Available(&size);
    if (NS_SUCCEEDED(res) && size <= INT64_MAX) {
      mSize = (int64_t)size;
    }
  }
  mSizeInitialized = true;
  if (!mNotifyDataEndedProcessed && mSize >= 0) {
    mCallback->AbstractMainThread()->Dispatch(NewRunnableMethod<nsresult>(
        "MediaResourceCallback::NotifyDataEnded", mCallback.get(),
        &MediaResourceCallback::NotifyDataEnded, NS_OK));
  }
  mNotifyDataEndedProcessed = true;
}

nsresult FileMediaResource::GetCachedRanges(MediaByteRangeSet& aRanges) {
  MutexAutoLock lock(mLock);

  EnsureSizeInitialized();
  if (mSize == -1) {
    return NS_ERROR_FAILURE;
  }
  aRanges += MediaByteRange(0, mSize);
  return NS_OK;
}

nsresult FileMediaResource::Open(nsIStreamListener** aStreamListener) {
  NS_ASSERTION(NS_IsMainThread(), "Only call on main thread");
  MOZ_ASSERT(aStreamListener);

  *aStreamListener = nullptr;
  nsresult rv = NS_OK;

  // The channel is already open. We need a synchronous stream that
  // implements nsISeekableStream, so we have to find the underlying
  // file and reopen it
  nsCOMPtr<nsIFileChannel> fc(do_QueryInterface(mChannel));
  if (fc) {
    nsCOMPtr<nsIFile> file;
    rv = fc->GetFile(getter_AddRefs(file));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = NS_NewLocalFileInputStream(getter_AddRefs(mInput), file, -1, -1,
                                    nsIFileInputStream::SHARE_DELETE);
  } else if (IsBlobURI(mURI)) {
    rv = NS_GetStreamForBlobURI(mURI, getter_AddRefs(mInput));
  }

  NS_ENSURE_SUCCESS(rv, rv);

  mSeekable = do_QueryInterface(mInput);
  if (!mSeekable) {
    // XXX The file may just be a .url or similar
    // shortcut that points to a Web site. We need to fix this by
    // doing an async open and waiting until we locate the real resource,
    // then using that (if it's still a file!).
    return NS_ERROR_FAILURE;
  }

  return NS_OK;
}

nsresult FileMediaResource::Close() {
  NS_ASSERTION(NS_IsMainThread(), "Only call on main thread");

  // Since mChennel is only accessed by main thread, there is no necessary to
  // take the lock.
  if (mChannel) {
    mChannel->Cancel(NS_ERROR_PARSED_DATA_CACHED);
    mChannel = nullptr;
  }

  return NS_OK;
}

already_AddRefed<nsIPrincipal> FileMediaResource::GetCurrentPrincipal() {
  NS_ASSERTION(NS_IsMainThread(), "Only call on main thread");

  nsCOMPtr<nsIPrincipal> principal;
  nsIScriptSecurityManager* secMan = nsContentUtils::GetSecurityManager();
  if (!secMan || !mChannel) return nullptr;
  secMan->GetChannelResultPrincipal(mChannel, getter_AddRefs(principal));
  return principal.forget();
}

nsresult FileMediaResource::ReadFromCache(char* aBuffer, int64_t aOffset,
                                          uint32_t aCount) {
  MutexAutoLock lock(mLock);

  EnsureSizeInitialized();
  if (!aCount) {
    return NS_OK;
  }
  int64_t offset = 0;
  nsresult res = mSeekable->Tell(&offset);
  NS_ENSURE_SUCCESS(res, res);
  res = mSeekable->Seek(nsISeekableStream::NS_SEEK_SET, aOffset);
  NS_ENSURE_SUCCESS(res, res);
  uint32_t bytesRead = 0;
  do {
    uint32_t x = 0;
    uint32_t bytesToRead = aCount - bytesRead;
    res = mInput->Read(aBuffer, bytesToRead, &x);
    bytesRead += x;
    if (!x) {
      res = NS_ERROR_FAILURE;
    }
  } while (bytesRead != aCount && res == NS_OK);

  // Reset read head to original position so we don't disturb any other
  // reading thread.
  nsresult seekres = mSeekable->Seek(nsISeekableStream::NS_SEEK_SET, offset);

  // If a read failed in the loop above, we want to return its failure code.
  NS_ENSURE_SUCCESS(res, res);

  // Else we succeed if the reset-seek succeeds.
  return seekres;
}

nsresult FileMediaResource::UnsafeRead(char* aBuffer, uint32_t aCount,
                                       uint32_t* aBytes) {
  EnsureSizeInitialized();
  return mInput->Read(aBuffer, aCount, aBytes);
}

nsresult FileMediaResource::ReadAt(int64_t aOffset, char* aBuffer,
                                   uint32_t aCount, uint32_t* aBytes) {
  NS_ASSERTION(!NS_IsMainThread(), "Don't call on main thread");

  nsresult rv;
  {
    MutexAutoLock lock(mLock);
    rv = UnsafeSeek(nsISeekableStream::NS_SEEK_SET, aOffset);
    if (NS_FAILED(rv)) return rv;
    rv = UnsafeRead(aBuffer, aCount, aBytes);
  }
  return rv;
}

already_AddRefed<MediaByteBuffer> FileMediaResource::UnsafeMediaReadAt(
    int64_t aOffset, uint32_t aCount) {
  RefPtr<MediaByteBuffer> bytes = new MediaByteBuffer();
  bool ok = bytes->SetLength(aCount, fallible);
  NS_ENSURE_TRUE(ok, nullptr);
  nsresult rv = UnsafeSeek(nsISeekableStream::NS_SEEK_SET, aOffset);
  NS_ENSURE_SUCCESS(rv, nullptr);
  char* curr = reinterpret_cast<char*>(bytes->Elements());
  const char* start = curr;
  while (aCount > 0) {
    uint32_t bytesRead;
    rv = UnsafeRead(curr, aCount, &bytesRead);
    NS_ENSURE_SUCCESS(rv, nullptr);
    if (!bytesRead) {
      break;
    }
    aCount -= bytesRead;
    curr += bytesRead;
  }
  bytes->SetLength(curr - start);
  return bytes.forget();
}

nsresult FileMediaResource::UnsafeSeek(int32_t aWhence, int64_t aOffset) {
  NS_ASSERTION(!NS_IsMainThread(), "Don't call on main thread");

  if (!mSeekable) return NS_ERROR_FAILURE;
  EnsureSizeInitialized();
  return mSeekable->Seek(aWhence, aOffset);
}

}  // namespace mozilla