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
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* 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/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include <ThreadedDeflater.hxx>
#include <zlib.h>
#include <com/sun/star/packages/zip/ZipConstants.hpp>
#include <sal/log.hxx>
using namespace com::sun::star::packages::zip::ZipConstants;
using namespace com::sun::star;
namespace ZipUtils
{
const sal_Int64 MaxBlockSize = 128 * 1024;
// Parallel ZLIB compression using threads. The class internally splits the data into
// blocks and spawns ThreadPool tasks to process them independently. This is achieved
// in a similar way how pigz works, see comments from Mark Adler at
// https://stackoverflow.com/questions/30294766/how-to-use-multiple-threads-for-zlib-compression
// and
// https://stackoverflow.com/questions/30794053/how-to-use-multiple-threads-for-zlib-compression-same-input-source
// Everything here should be either read-only, or writing to distinct data, or atomic.
class ThreadedDeflater::Task : public comphelper::ThreadTask
{
z_stream stream;
ThreadedDeflater* deflater;
int sequence;
int blockSize;
bool firstTask : 1;
bool lastTask : 1;
public:
Task(ThreadedDeflater* deflater_, int sequence_, int blockSize_, bool firstTask_,
bool lastTask_)
: comphelper::ThreadTask(deflater_->threadTaskTag)
, stream()
, deflater(deflater_)
, sequence(sequence_)
, blockSize(blockSize_)
, firstTask(firstTask_)
, lastTask(lastTask_)
{
}
private:
virtual void doWork() override;
};
ThreadedDeflater::ThreadedDeflater(sal_Int32 nSetLevel)
: threadTaskTag(comphelper::ThreadPool::createThreadTaskTag())
, totalIn(0)
, totalOut(0)
, zlibLevel(nSetLevel)
{
}
ThreadedDeflater::~ThreadedDeflater() COVERITY_NOEXCEPT_FALSE { clear(); }
void ThreadedDeflater::deflateWrite(
const css::uno::Reference<css::io::XInputStream>& xInStream,
const std::function<void(const css::uno::Sequence<sal_Int8>&, sal_Int32)>& rProcessInputFunc,
const std::function<void(const css::uno::Sequence<sal_Int8>&, sal_Int32)>& rProcessOutputFunc)
{
sal_Int64 nThreadCount = comphelper::ThreadPool::getSharedOptimalPool().getWorkerCount();
sal_Int64 batchSize = MaxBlockSize * nThreadCount;
inBuffer.realloc(batchSize);
prevDataBlock.realloc(MaxBlockSize);
outBuffers.resize(nThreadCount);
maProcessOutputFunc = rProcessOutputFunc;
bool firstTask = true;
while (xInStream->available() > 0)
{
sal_Int64 inputBytes = xInStream->readBytes(inBuffer, batchSize);
rProcessInputFunc(inBuffer, inputBytes);
totalIn += inputBytes;
int sequence = 0;
bool lastBatch = xInStream->available() <= 0;
sal_Int64 bytesPending = inputBytes;
while (bytesPending > 0)
{
sal_Int64 taskSize = std::min(MaxBlockSize, bytesPending);
bytesPending -= taskSize;
bool lastTask = lastBatch && !bytesPending;
comphelper::ThreadPool::getSharedOptimalPool().pushTask(
std::make_unique<Task>(this, sequence++, taskSize, firstTask, lastTask));
if (firstTask)
firstTask = false;
}
assert(bytesPending == 0);
comphelper::ThreadPool::getSharedOptimalPool().waitUntilDone(threadTaskTag);
if (!lastBatch)
{
assert(inputBytes == batchSize);
std::copy_n(std::cbegin(inBuffer) + (batchSize - MaxBlockSize), MaxBlockSize,
prevDataBlock.getArray());
}
processDeflatedBuffers();
}
}
void ThreadedDeflater::processDeflatedBuffers()
{
sal_Int64 batchOutputSize = 0;
for (const auto& buffer : outBuffers)
batchOutputSize += buffer.size();
css::uno::Sequence<sal_Int8> outBuffer(batchOutputSize);
auto pos = outBuffer.getArray();
for (auto& buffer : outBuffers)
{
pos = std::copy(buffer.begin(), buffer.end(), pos);
buffer.clear();
}
maProcessOutputFunc(outBuffer, batchOutputSize);
totalOut += batchOutputSize;
}
void ThreadedDeflater::clear()
{
inBuffer = uno::Sequence<sal_Int8>();
outBuffers.clear();
}
#if defined Z_PREFIX
#define deflateInit2 z_deflateInit2
#define deflateBound z_deflateBound
#define deflateSetDictionary z_deflateSetDictionary
#define deflate z_deflate
#define deflateEnd z_deflateEnd
#endif
void ThreadedDeflater::Task::doWork()
{
stream.zalloc = nullptr;
stream.zfree = nullptr;
stream.opaque = nullptr;
// -MAX_WBITS means 32k window size and raw stream
if (deflateInit2(&stream, deflater->zlibLevel, Z_DEFLATED, -MAX_WBITS, DEF_MEM_LEVEL,
Z_DEFAULT_STRATEGY)
!= Z_OK)
{
SAL_WARN("package.threadeddeflate", "deflateInit2() failed");
abort();
}
// Find out size for our output buffer to be large enough for deflate() needing to be called just once.
sal_Int64 outputMaxSize = deflateBound(&stream, blockSize);
// add extra size for Z_SYNC_FLUSH
outputMaxSize += 20;
deflater->outBuffers[sequence].resize(outputMaxSize);
sal_Int64 myInBufferStart = sequence * MaxBlockSize;
// zlib doesn't handle const properly
unsigned char* inBufferPtr = reinterpret_cast<unsigned char*>(
const_cast<signed char*>(deflater->inBuffer.getConstArray()));
if (!firstTask)
{
// the window size is 32k, so set last 32k of previous data as the dictionary
assert(MAX_WBITS == 15);
assert(MaxBlockSize >= 32768);
if (sequence > 0)
{
deflateSetDictionary(&stream, inBufferPtr + myInBufferStart - 32768, 32768);
}
else
{
unsigned char* prevBufferPtr = reinterpret_cast<unsigned char*>(
const_cast<signed char*>(deflater->prevDataBlock.getConstArray()));
deflateSetDictionary(&stream, prevBufferPtr + MaxBlockSize - 32768, 32768);
}
}
stream.next_in = inBufferPtr + myInBufferStart;
stream.avail_in = blockSize;
stream.next_out = reinterpret_cast<unsigned char*>(deflater->outBuffers[sequence].data());
stream.avail_out = outputMaxSize;
// The trick is in using Z_SYNC_FLUSH instead of Z_NO_FLUSH. It will align the data at a byte boundary,
// and since we use a raw stream, the data blocks then can be simply concatenated.
int res = deflate(&stream, lastTask ? Z_FINISH : Z_SYNC_FLUSH);
assert(stream.avail_in == 0); // Check that everything has been deflated.
if (lastTask ? res == Z_STREAM_END : res == Z_OK)
{ // ok
sal_Int64 outSize = outputMaxSize - stream.avail_out;
deflater->outBuffers[sequence].resize(outSize);
}
else
{
SAL_WARN("package.threadeddeflate", "deflate() failed");
abort();
}
deflateEnd(&stream);
}
} // namespace
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|
