| /* |
| * Copyright (C) 2010 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "Blob.h" |
| |
| #include "FileSystem.h" |
| |
| namespace WebCore { |
| |
| #if ENABLE(BLOB_SLICE) |
| const int Blob::toEndOfFile = -1; |
| const double Blob::doNotCheckFileChange = 0; |
| #endif |
| |
| Blob::Blob(const String& path) |
| : m_path(path) |
| #if ENABLE(BLOB_SLICE) |
| , m_start(0) |
| , m_length(toEndOfFile) |
| , m_snapshotCaptured(false) |
| , m_snapshotSize(0) |
| , m_snapshotModificationTime(doNotCheckFileChange) |
| #endif |
| { |
| } |
| |
| #if ENABLE(BLOB_SLICE) |
| Blob::Blob(const String& path, long long start, long long length, long long snapshotSize, double snapshotModificationTime) |
| : m_path(path) |
| , m_start(start) |
| , m_length(length) |
| , m_snapshotCaptured(true) |
| , m_snapshotSize(snapshotSize) |
| , m_snapshotModificationTime(snapshotModificationTime) |
| { |
| ASSERT(start >= 0 && length >= 0 && start + length <= snapshotSize && snapshotModificationTime); |
| } |
| #endif |
| |
| unsigned long long Blob::size() const |
| { |
| // FIXME: JavaScript cannot represent sizes as large as unsigned long long, we need to |
| // come up with an exception to throw if file size is not represetable. |
| #if ENABLE(BLOB_SLICE) |
| if (m_snapshotCaptured) |
| return m_length; |
| #endif |
| long long size; |
| if (!getFileSize(m_path, size)) |
| return 0; |
| return static_cast<unsigned long long>(size); |
| } |
| |
| #if ENABLE(BLOB_SLICE) |
| PassRefPtr<Blob> Blob::slice(long long start, long long length) const |
| { |
| // When we slice a file for the first time, we obtain a snapshot of the file by capturing its current size and modification time. |
| // The modification time will be used to verify if the file has been changed or not, when the underlying data are accessed. |
| long long snapshotSize; |
| double snapshotModificationTime; |
| if (m_snapshotCaptured) { |
| snapshotSize = m_snapshotSize; |
| snapshotModificationTime = m_snapshotModificationTime; |
| } else { |
| // If we fail to retrieve the size or modification time, probably due to that the file has been deleted, an empty blob will be returned. |
| time_t modificationTime; |
| if (!getFileSize(m_path, snapshotSize) || !getFileModificationTime(m_path, modificationTime)) { |
| snapshotSize = 0; |
| snapshotModificationTime = 0; |
| } else |
| snapshotModificationTime = modificationTime; |
| } |
| |
| // Clamp the range if it exceeds the size limit. |
| if (start < 0) |
| start = 0; |
| if (length < 0) |
| length = 0; |
| |
| if (start > snapshotSize) { |
| start = 0; |
| length = 0; |
| } else if (start + length > snapshotSize) |
| length = snapshotSize - start; |
| |
| return adoptRef(new Blob(m_path, m_start + start, length, snapshotSize, snapshotModificationTime)); |
| } |
| #endif |
| |
| } // namespace WebCore |