1// Protocol Buffers - Google's data interchange format
2// Copyright 2008 Google Inc. All rights reserved.
3// https://developers.google.com/protocol-buffers/
4//
5// Redistribution and use in source and binary forms, with or without
6// modification, are permitted provided that the following conditions are
7// met:
8//
9// * Redistributions of source code must retain the above copyright
10// notice, this list of conditions and the following disclaimer.
11// * Redistributions in binary form must reproduce the above
12// copyright notice, this list of conditions and the following disclaimer
13// in the documentation and/or other materials provided with the
14// distribution.
15// * Neither the name of Google Inc. nor the names of its
16// contributors may be used to endorse or promote products derived from
17// this software without specific prior written permission.
18//
19// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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29// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31// Author: ambrose@google.com (Ambrose Feinstein),
32// kenton@google.com (Kenton Varda)
33//
34// Based on http://www.pkware.com/documents/casestudies/APPNOTE.TXT
35
36#include <google/protobuf/compiler/zip_writer.h>
37
38#include <cstdint>
39
40#include <google/protobuf/io/coded_stream.h>
41
42namespace google {
43namespace protobuf {
44namespace compiler {
45
46// January 1, 1980 as a DOS date.
47// see https://msdn.microsoft.com/en-us/library/9kkf9tah.aspx
48static const uint16_t kDosEpoch = 1 << 5 | 1;
49
50static const uint32_t kCRC32Table[256] = {
51 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
52 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
53 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
54 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
55 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
56 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
57 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
58 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
59 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
60 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
61 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
62 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
63 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
64 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
65 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
66 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
67 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
68 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
69 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
70 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
71 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
72 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
73 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
74 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
75 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
76 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
77 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
78 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
79 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
80 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
81 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
82 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
83 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
84 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
85 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
86 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
87 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
88 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
89 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
90 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
91 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
92 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
93 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d};
94
95static uint32_t ComputeCRC32(const std::string& buf) {
96 uint32_t x = ~0U;
97 for (int i = 0; i < buf.size(); ++i) {
98 unsigned char c = buf[i];
99 x = kCRC32Table[(x ^ c) & 0xff] ^ (x >> 8);
100 }
101 return ~x;
102}
103
104static void WriteShort(io::CodedOutputStream* out, uint16_t val) {
105 uint8_t p[2];
106 p[0] = static_cast<uint8_t>(val);
107 p[1] = static_cast<uint8_t>(val >> 8);
108 out->WriteRaw(buffer: p, size: 2);
109}
110
111ZipWriter::ZipWriter(io::ZeroCopyOutputStream* raw_output)
112 : raw_output_(raw_output) {}
113ZipWriter::~ZipWriter() {}
114
115bool ZipWriter::Write(const std::string& filename,
116 const std::string& contents) {
117 FileInfo info;
118
119 info.name = filename;
120 uint16_t filename_size = filename.size();
121 info.offset = raw_output_->ByteCount();
122 info.size = contents.size();
123 info.crc32 = ComputeCRC32(buf: contents);
124
125 files_.push_back(x: info);
126
127 // write file header
128 io::CodedOutputStream output(raw_output_);
129 output.WriteLittleEndian32(value: 0x04034b50); // magic
130 WriteShort(out: &output, val: 10); // version needed to extract
131 WriteShort(out: &output, val: 0); // flags
132 WriteShort(out: &output, val: 0); // compression method: stored
133 WriteShort(out: &output, val: 0); // last modified time
134 WriteShort(out: &output, val: kDosEpoch); // last modified date
135 output.WriteLittleEndian32(value: info.crc32); // crc-32
136 output.WriteLittleEndian32(value: info.size); // compressed size
137 output.WriteLittleEndian32(value: info.size); // uncompressed size
138 WriteShort(out: &output, val: filename_size); // file name length
139 WriteShort(out: &output, val: 0); // extra field length
140 output.WriteString(str: filename); // file name
141 output.WriteString(str: contents); // file data
142
143 return !output.HadError();
144}
145
146bool ZipWriter::WriteDirectory() {
147 uint16_t num_entries = files_.size();
148 uint32_t dir_ofs = raw_output_->ByteCount();
149
150 // write central directory
151 io::CodedOutputStream output(raw_output_);
152 for (int i = 0; i < num_entries; ++i) {
153 const std::string& filename = files_[i].name;
154 uint16_t filename_size = filename.size();
155 uint32_t crc32 = files_[i].crc32;
156 uint32_t size = files_[i].size;
157 uint32_t offset = files_[i].offset;
158
159 output.WriteLittleEndian32(value: 0x02014b50); // magic
160 WriteShort(out: &output, val: 10); // version made by
161 WriteShort(out: &output, val: 10); // version needed to extract
162 WriteShort(out: &output, val: 0); // flags
163 WriteShort(out: &output, val: 0); // compression method: stored
164 WriteShort(out: &output, val: 0); // last modified time
165 WriteShort(out: &output, val: kDosEpoch); // last modified date
166 output.WriteLittleEndian32(value: crc32); // crc-32
167 output.WriteLittleEndian32(value: size); // compressed size
168 output.WriteLittleEndian32(value: size); // uncompressed size
169 WriteShort(out: &output, val: filename_size); // file name length
170 WriteShort(out: &output, val: 0); // extra field length
171 WriteShort(out: &output, val: 0); // file comment length
172 WriteShort(out: &output, val: 0); // starting disk number
173 WriteShort(out: &output, val: 0); // internal file attributes
174 output.WriteLittleEndian32(value: 0); // external file attributes
175 output.WriteLittleEndian32(value: offset); // local header offset
176 output.WriteString(str: filename); // file name
177 }
178 uint32_t dir_len = output.ByteCount();
179
180 // write end of central directory marker
181 output.WriteLittleEndian32(value: 0x06054b50); // magic
182 WriteShort(out: &output, val: 0); // disk number
183 WriteShort(out: &output, val: 0); // disk with start of central directory
184 WriteShort(out: &output, val: num_entries); // central directory entries (this disk)
185 WriteShort(out: &output, val: num_entries); // central directory entries (total)
186 output.WriteLittleEndian32(value: dir_len); // central directory byte size
187 output.WriteLittleEndian32(value: dir_ofs); // central directory offset
188 WriteShort(out: &output, val: 0); // comment length
189
190 return output.HadError();
191}
192
193} // namespace compiler
194} // namespace protobuf
195} // namespace google
196