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
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
|
/*-
* Copyright (c) 2003-2007 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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 AUTHOR(S) 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 "archive_platform.h"
/* Don't compile this if we don't have zlib. */
#if HAVE_ZLIB_H
__FBSDID("$FreeBSD$");
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <time.h>
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif
#include "archive.h"
#include "archive_private.h"
#include "archive_write_private.h"
struct private_data {
z_stream stream;
int64_t total_in;
unsigned char *compressed;
size_t compressed_buffer_size;
unsigned long crc;
};
/*
* Yuck. zlib.h is not const-correct, so I need this one bit
* of ugly hackery to convert a const * pointer to a non-const pointer.
*/
#define SET_NEXT_IN(st,src) \
(st)->stream.next_in = (Bytef *)(uintptr_t)(const void *)(src)
static int archive_compressor_gzip_finish(struct archive_write *);
static int archive_compressor_gzip_init(struct archive_write *);
static int archive_compressor_gzip_write(struct archive_write *,
const void *, size_t);
static int drive_compressor(struct archive_write *, struct private_data *,
int finishing);
/*
* Allocate, initialize and return a archive object.
*/
int
archive_write_set_compression_gzip(struct archive *_a)
{
struct archive_write *a = (struct archive_write *)_a;
__archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
ARCHIVE_STATE_NEW, "archive_write_set_compression_gzip");
a->compression_init = &archive_compressor_gzip_init;
a->archive.compression_code = ARCHIVE_COMPRESSION_GZIP;
a->archive.compression_name = "gzip";
return (ARCHIVE_OK);
}
/*
* Setup callback.
*/
static int
archive_compressor_gzip_init(struct archive_write *a)
{
int ret;
struct private_data *state;
time_t t;
a->archive.compression_code = ARCHIVE_COMPRESSION_GZIP;
a->archive.compression_name = "gzip";
if (a->client_opener != NULL) {
ret = (a->client_opener)(&a->archive, a->client_data);
if (ret != ARCHIVE_OK)
return (ret);
}
state = (struct private_data *)malloc(sizeof(*state));
if (state == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate data for compression");
return (ARCHIVE_FATAL);
}
memset(state, 0, sizeof(*state));
state->compressed_buffer_size = a->bytes_per_block;
state->compressed = (unsigned char *)malloc(state->compressed_buffer_size);
state->crc = crc32(0L, NULL, 0);
if (state->compressed == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate data for compression buffer");
free(state);
return (ARCHIVE_FATAL);
}
state->stream.next_out = state->compressed;
state->stream.avail_out = state->compressed_buffer_size;
/* Prime output buffer with a gzip header. */
t = time(NULL);
state->compressed[0] = 0x1f; /* GZip signature bytes */
state->compressed[1] = 0x8b;
state->compressed[2] = 0x08; /* "Deflate" compression */
state->compressed[3] = 0; /* No options */
state->compressed[4] = (t)&0xff; /* Timestamp */
state->compressed[5] = (t>>8)&0xff;
state->compressed[6] = (t>>16)&0xff;
state->compressed[7] = (t>>24)&0xff;
state->compressed[8] = 0; /* No deflate options */
state->compressed[9] = 3; /* OS=Unix */
state->stream.next_out += 10;
state->stream.avail_out -= 10;
a->compression_write = archive_compressor_gzip_write;
a->compression_finish = archive_compressor_gzip_finish;
/* Initialize compression library. */
ret = deflateInit2(&(state->stream),
Z_DEFAULT_COMPRESSION,
Z_DEFLATED,
-15 /* < 0 to suppress zlib header */,
8,
Z_DEFAULT_STRATEGY);
if (ret == Z_OK) {
a->compression_data = state;
return (0);
}
/* Library setup failed: clean up. */
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Internal error "
"initializing compression library");
free(state->compressed);
free(state);
/* Override the error message if we know what really went wrong. */
switch (ret) {
case Z_STREAM_ERROR:
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Internal error initializing "
"compression library: invalid setup parameter");
break;
case Z_MEM_ERROR:
archive_set_error(&a->archive, ENOMEM, "Internal error initializing "
"compression library");
break;
case Z_VERSION_ERROR:
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Internal error initializing "
"compression library: invalid library version");
break;
}
return (ARCHIVE_FATAL);
}
/*
* Write data to the compressed stream.
*/
static int
archive_compressor_gzip_write(struct archive_write *a, const void *buff,
size_t length)
{
struct private_data *state;
int ret;
state = (struct private_data *)a->compression_data;
if (a->client_writer == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
"No write callback is registered? "
"This is probably an internal programming error.");
return (ARCHIVE_FATAL);
}
/* Update statistics */
state->crc = crc32(state->crc, (const Bytef *)buff, length);
state->total_in += length;
/* Compress input data to output buffer */
SET_NEXT_IN(state, buff);
state->stream.avail_in = length;
if ((ret = drive_compressor(a, state, 0)) != ARCHIVE_OK)
return (ret);
a->archive.file_position += length;
return (ARCHIVE_OK);
}
/*
* Finish the compression...
*/
static int
archive_compressor_gzip_finish(struct archive_write *a)
{
ssize_t block_length, target_block_length, bytes_written;
int ret;
struct private_data *state;
unsigned tocopy;
unsigned char trailer[8];
state = (struct private_data *)a->compression_data;
ret = 0;
if (a->client_writer == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
"No write callback is registered? "
"This is probably an internal programming error.");
ret = ARCHIVE_FATAL;
goto cleanup;
}
/* By default, always pad the uncompressed data. */
if (a->pad_uncompressed) {
tocopy = a->bytes_per_block -
(state->total_in % a->bytes_per_block);
while (tocopy > 0 && tocopy < (unsigned)a->bytes_per_block) {
SET_NEXT_IN(state, a->nulls);
state->stream.avail_in = tocopy < a->null_length ?
tocopy : a->null_length;
state->crc = crc32(state->crc, a->nulls,
state->stream.avail_in);
state->total_in += state->stream.avail_in;
tocopy -= state->stream.avail_in;
ret = drive_compressor(a, state, 0);
if (ret != ARCHIVE_OK)
goto cleanup;
}
}
/* Finish compression cycle */
if (((ret = drive_compressor(a, state, 1))) != ARCHIVE_OK)
goto cleanup;
/* Build trailer: 4-byte CRC and 4-byte length. */
trailer[0] = (state->crc)&0xff;
trailer[1] = (state->crc >> 8)&0xff;
trailer[2] = (state->crc >> 16)&0xff;
trailer[3] = (state->crc >> 24)&0xff;
trailer[4] = (state->total_in)&0xff;
trailer[5] = (state->total_in >> 8)&0xff;
trailer[6] = (state->total_in >> 16)&0xff;
trailer[7] = (state->total_in >> 24)&0xff;
/* Add trailer to current block. */
tocopy = 8;
if (tocopy > state->stream.avail_out)
tocopy = state->stream.avail_out;
memcpy(state->stream.next_out, trailer, tocopy);
state->stream.next_out += tocopy;
state->stream.avail_out -= tocopy;
/* If it overflowed, flush and start a new block. */
if (tocopy < 8) {
bytes_written = (a->client_writer)(&a->archive, a->client_data,
state->compressed, state->compressed_buffer_size);
if (bytes_written <= 0) {
ret = ARCHIVE_FATAL;
goto cleanup;
}
a->archive.raw_position += bytes_written;
state->stream.next_out = state->compressed;
state->stream.avail_out = state->compressed_buffer_size;
memcpy(state->stream.next_out, trailer + tocopy, 8-tocopy);
state->stream.next_out += 8-tocopy;
state->stream.avail_out -= 8-tocopy;
}
/* Optionally, pad the final compressed block. */
block_length = state->stream.next_out - state->compressed;
/* Tricky calculation to determine size of last block. */
target_block_length = block_length;
if (a->bytes_in_last_block <= 0)
/* Default or Zero: pad to full block */
target_block_length = a->bytes_per_block;
else
/* Round length to next multiple of bytes_in_last_block. */
target_block_length = a->bytes_in_last_block *
( (block_length + a->bytes_in_last_block - 1) /
a->bytes_in_last_block);
if (target_block_length > a->bytes_per_block)
target_block_length = a->bytes_per_block;
if (block_length < target_block_length) {
memset(state->stream.next_out, 0,
target_block_length - block_length);
block_length = target_block_length;
}
/* Write the last block */
bytes_written = (a->client_writer)(&a->archive, a->client_data,
state->compressed, block_length);
if (bytes_written <= 0) {
ret = ARCHIVE_FATAL;
goto cleanup;
}
a->archive.raw_position += bytes_written;
/* Cleanup: shut down compressor, release memory, etc. */
cleanup:
switch (deflateEnd(&(state->stream))) {
case Z_OK:
break;
default:
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Failed to clean up compressor");
ret = ARCHIVE_FATAL;
}
free(state->compressed);
free(state);
/* Close the output */
if (a->client_closer != NULL)
(a->client_closer)(&a->archive, a->client_data);
return (ret);
}
/*
* Utility function to push input data through compressor,
* writing full output blocks as necessary.
*
* Note that this handles both the regular write case (finishing ==
* false) and the end-of-archive case (finishing == true).
*/
static int
drive_compressor(struct archive_write *a, struct private_data *state, int finishing)
{
ssize_t bytes_written;
int ret;
for (;;) {
if (state->stream.avail_out == 0) {
bytes_written = (a->client_writer)(&a->archive,
a->client_data, state->compressed,
state->compressed_buffer_size);
if (bytes_written <= 0) {
/* TODO: Handle this write failure */
return (ARCHIVE_FATAL);
} else if ((size_t)bytes_written < state->compressed_buffer_size) {
/* Short write: Move remaining to
* front of block and keep filling */
memmove(state->compressed,
state->compressed + bytes_written,
state->compressed_buffer_size - bytes_written);
}
a->archive.raw_position += bytes_written;
state->stream.next_out
= state->compressed +
state->compressed_buffer_size - bytes_written;
state->stream.avail_out = bytes_written;
}
ret = deflate(&(state->stream),
finishing ? Z_FINISH : Z_NO_FLUSH );
switch (ret) {
case Z_OK:
/* In non-finishing case, check if compressor
* consumed everything */
if (!finishing && state->stream.avail_in == 0)
return (ARCHIVE_OK);
/* In finishing case, this return always means
* there's more work */
break;
case Z_STREAM_END:
/* This return can only occur in finishing case. */
return (ARCHIVE_OK);
default:
/* Any other return value indicates an error. */
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"GZip compression failed");
return (ARCHIVE_FATAL);
}
}
}
#endif /* HAVE_ZLIB_H */
|