blob: 1d6f17822c805281b70a41620dcdee6ad2ab889c [file] [log] [blame]
/*
* Copyright (C) 2012 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 "WebSocketDeflater.h"
#if USE(ZLIB)
#include "Logging.h"
#include <wtf/FastMalloc.h>
#include <wtf/HashMap.h>
#include <wtf/StdLibExtras.h>
#include <wtf/text/StringHash.h>
#include <wtf/text/WTFString.h>
#include <zlib.h>
namespace WebCore {
static const int defaultMemLevel = 8;
static const size_t bufferIncrementUnit = 4096;
WebSocketDeflater::WebSocketDeflater(int windowBits, ContextTakeOverMode contextTakeOverMode)
: m_windowBits(windowBits)
, m_contextTakeOverMode(contextTakeOverMode)
{
ASSERT(m_windowBits >= 8);
ASSERT(m_windowBits <= 15);
m_stream = std::make_unique<z_stream>();
memset(m_stream.get(), 0, sizeof(z_stream));
}
bool WebSocketDeflater::initialize()
{
return deflateInit2(m_stream.get(), Z_DEFAULT_COMPRESSION, Z_DEFLATED, -m_windowBits, defaultMemLevel, Z_DEFAULT_STRATEGY) == Z_OK;
}
WebSocketDeflater::~WebSocketDeflater()
{
int result = deflateEnd(m_stream.get());
if (result != Z_OK)
LOG(Network, "WebSocketDeflater %p Destructor deflateEnd() failed: %d is returned", this, result);
}
static void setStreamParameter(z_stream* stream, const char* inputData, size_t inputLength, char* outputData, size_t outputLength)
{
stream->next_in = reinterpret_cast<Bytef*>(const_cast<char*>(inputData));
stream->avail_in = inputLength;
stream->next_out = reinterpret_cast<Bytef*>(outputData);
stream->avail_out = outputLength;
}
bool WebSocketDeflater::addBytes(const char* data, size_t length)
{
if (!length)
return false;
size_t maxLength = deflateBound(m_stream.get(), length);
size_t writePosition = m_buffer.size();
m_buffer.grow(writePosition + maxLength);
setStreamParameter(m_stream.get(), data, length, m_buffer.data() + writePosition, maxLength);
int result = deflate(m_stream.get(), Z_NO_FLUSH);
if (result != Z_OK || m_stream->avail_in > 0)
return false;
m_buffer.shrink(writePosition + maxLength - m_stream->avail_out);
return true;
}
bool WebSocketDeflater::finish()
{
while (true) {
size_t writePosition = m_buffer.size();
m_buffer.grow(writePosition + bufferIncrementUnit);
size_t availableCapacity = m_buffer.size() - writePosition;
setStreamParameter(m_stream.get(), 0, 0, m_buffer.data() + writePosition, availableCapacity);
int result = deflate(m_stream.get(), Z_SYNC_FLUSH);
m_buffer.shrink(writePosition + availableCapacity - m_stream->avail_out);
if (result == Z_OK)
break;
if (result != Z_BUF_ERROR)
return false;
}
// Remove 4 octets from the tail as the specification requires.
if (m_buffer.size() <= 4)
return false;
m_buffer.shrink(m_buffer.size() - 4);
return true;
}
void WebSocketDeflater::reset()
{
m_buffer.clear();
if (m_contextTakeOverMode == DoNotTakeOverContext)
deflateReset(m_stream.get());
}
WebSocketInflater::WebSocketInflater(int windowBits)
: m_windowBits(windowBits)
{
m_stream = std::make_unique<z_stream>();
memset(m_stream.get(), 0, sizeof(z_stream));
}
bool WebSocketInflater::initialize()
{
return inflateInit2(m_stream.get(), -m_windowBits) == Z_OK;
}
WebSocketInflater::~WebSocketInflater()
{
int result = inflateEnd(m_stream.get());
if (result != Z_OK)
LOG(Network, "WebSocketInflater %p Destructor inflateEnd() failed: %d is returned", this, result);
}
bool WebSocketInflater::addBytes(const char* data, size_t length)
{
if (!length)
return false;
size_t consumedSoFar = 0;
while (consumedSoFar < length) {
size_t writePosition = m_buffer.size();
m_buffer.grow(writePosition + bufferIncrementUnit);
size_t availableCapacity = m_buffer.size() - writePosition;
size_t remainingLength = length - consumedSoFar;
setStreamParameter(m_stream.get(), data + consumedSoFar, remainingLength, m_buffer.data() + writePosition, availableCapacity);
int result = inflate(m_stream.get(), Z_NO_FLUSH);
consumedSoFar += remainingLength - m_stream->avail_in;
m_buffer.shrink(writePosition + availableCapacity - m_stream->avail_out);
if (result == Z_BUF_ERROR)
continue;
if (result == Z_STREAM_END) {
// Received a block with BFINAL set to 1. Reset decompression state.
if (inflateReset(m_stream.get()) != Z_OK)
return false;
continue;
}
if (result != Z_OK)
return false;
ASSERT(remainingLength > m_stream->avail_in);
}
ASSERT(consumedSoFar == length);
return true;
}
bool WebSocketInflater::finish()
{
static const char* strippedFields = "\0\0\xff\xff";
static const size_t strippedLength = 4;
// Appends 4 octests of 0x00 0x00 0xff 0xff
size_t consumedSoFar = 0;
while (consumedSoFar < strippedLength) {
size_t writePosition = m_buffer.size();
m_buffer.grow(writePosition + bufferIncrementUnit);
size_t availableCapacity = m_buffer.size() - writePosition;
size_t remainingLength = strippedLength - consumedSoFar;
setStreamParameter(m_stream.get(), strippedFields + consumedSoFar, remainingLength, m_buffer.data() + writePosition, availableCapacity);
int result = inflate(m_stream.get(), Z_FINISH);
consumedSoFar += remainingLength - m_stream->avail_in;
m_buffer.shrink(writePosition + availableCapacity - m_stream->avail_out);
if (result == Z_BUF_ERROR)
continue;
if (result != Z_OK && result != Z_STREAM_END)
return false;
ASSERT(remainingLength > m_stream->avail_in);
}
ASSERT(consumedSoFar == strippedLength);
return true;
}
void WebSocketInflater::reset()
{
m_buffer.clear();
}
} // namespace WebCore
#endif // USE(ZLIB)