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
|
/*
* Copyright (C) 2001-2019 Jacek Sieka, arnetheduck on gmail point com
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "stdinc.h"
#include "ZUtils.h"
#include "Exception.h"
#include "File.h"
#include "format.h"
#include "ScopedFunctor.h"
namespace dcpp {
using std::max;
const double ZFilter::MIN_COMPRESSION_LEVEL = 0.95;
ZFilter::ZFilter() : totalIn(0), totalOut(0), compressing(true) {
memset(&zs, 0, sizeof(zs));
if(deflateInit(&zs, 3) != Z_OK) {
throw Exception(_("Error during compression"));
}
}
ZFilter::~ZFilter() {
deflateEnd(&zs);
}
bool ZFilter::operator()(const void* in, size_t& insize, void* out, size_t& outsize) {
if(outsize == 0)
return false;
zs.next_in = (Bytef*)in;
zs.next_out = (Bytef*)out;
// Check if there's any use compressing; if not, save some cpu...
if(compressing && insize > 0 && outsize > 16 && (totalIn > (64 * 1024)) &&
(static_cast<double>(totalOut) / totalIn) > MIN_COMPRESSION_LEVEL)
{
zs.avail_in = 0;
zs.avail_out = outsize;
// Starting with zlib 1.2.9, the deflateParams API has changed.
auto err = ::deflateParams(&zs, 0, Z_DEFAULT_STRATEGY);
#if ZLIB_VERNUM >= 0x1290
if(err == Z_STREAM_ERROR) {
#else
if(err != Z_OK) {
#endif
throw Exception(_("Error during compression"));
}
zs.avail_in = insize;
compressing = false;
dcdebug("ZFilter: Dynamically disabled compression\n");
// Check if we ate all space already...
#if ZLIB_VERNUM >= 0x1290
if(err == Z_BUF_ERROR) {
#else
if(zs.avail_out == 0) {
#endif
outsize = outsize - zs.avail_out;
insize = insize - zs.avail_in;
totalOut += outsize;
totalIn += insize;
return true;
}
} else {
zs.avail_in = insize;
zs.avail_out = outsize;
}
if(insize == 0) {
int err = ::deflate(&zs, Z_FINISH);
if(err != Z_OK && err != Z_STREAM_END)
throw Exception(_("Error during compression"));
outsize = outsize - zs.avail_out;
insize = insize - zs.avail_in;
totalOut += outsize;
totalIn += insize;
return err == Z_OK;
} else {
int err = ::deflate(&zs, Z_NO_FLUSH);
if(err != Z_OK)
throw Exception(_("Error during compression"));
outsize = outsize - zs.avail_out;
insize = insize - zs.avail_in;
totalOut += outsize;
totalIn += insize;
return true;
}
}
UnZFilter::UnZFilter() {
memset(&zs, 0, sizeof(zs));
if(inflateInit(&zs) != Z_OK)
throw Exception(_("Error during decompression"));
}
UnZFilter::~UnZFilter() {
inflateEnd(&zs);
}
bool UnZFilter::operator()(const void* in, size_t& insize, void* out, size_t& outsize) {
if(outsize == 0)
return false;
zs.avail_in = insize;
zs.next_in = (Bytef*)in;
zs.avail_out = outsize;
zs.next_out = (Bytef*)out;
int err = ::inflate(&zs, Z_NO_FLUSH);
// see zlib/contrib/minizip/unzip.c, Z_BUF_ERROR means we should have padded
// with a dummy byte if at end of stream - since we don't do this it's not a real
// error
if(!(err == Z_OK || err == Z_STREAM_END || (err == Z_BUF_ERROR && in == NULL)))
throw Exception(_("Error during decompression"));
outsize = outsize - zs.avail_out;
insize = insize - zs.avail_in;
return err == Z_OK;
}
void GZ::decompress(const string& source, const string& target) {
#ifdef UNICODE
auto gz = gzopen_w(Text::toT(source).c_str(), "rb");
#else
auto gz = gzopen(source.c_str(), "rb");
#endif
if(!gz) {
throw Exception(_("Error during decompression"));
}
ScopedFunctor([&gz] { gzclose(gz); });
File f(target, File::WRITE, File::CREATE | File::TRUNCATE);
const size_t BUF_SIZE = 64 * 1024;
const int BUF_SIZE_INT = static_cast<int>(BUF_SIZE);
ByteVector buf(BUF_SIZE);
while(true) {
auto read = gzread(gz, &buf[0], BUF_SIZE);
if(read > 0) {
f.write(&buf[0], read);
}
if(read < BUF_SIZE_INT) {
break;
}
}
}
} // namespace dcpp
|
