contrib/libarchive/libarchive/archive_write_set_compression_gzip.c

   1 /*-
   2  * Copyright (c) 2003-2007 Tim Kientzle
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "archive_platform.h"
  27
  28 __FBSDID("$FreeBSD: head/lib/libarchive/archive_write_set_compression_gzip.c 201081 2009-12-28 02:04:42Z kientzle $");
  29
  30 #ifdef HAVE_ERRNO_H
  31 #include <errno.h>
  32 #endif
  33 #ifdef HAVE_STDLIB_H
  34 #include <stdlib.h>
  35 #endif
  36 #ifdef HAVE_STRING_H
  37 #include <string.h>
  38 #endif
  39 #include <time.h>
  40 #ifdef HAVE_ZLIB_H
  41 #include <zlib.h>
  42 #endif
  43
  44 #include "archive.h"
  45 #include "archive_private.h"
  46 #include "archive_write_private.h"
  47
  48 #ifndef HAVE_ZLIB_H
  49 int
  50 archive_write_set_compression_gzip(struct archive *a)
  51 {
  52         archive_set_error(a, ARCHIVE_ERRNO_MISC,
  53             "gzip compression not supported on this platform");
  54         return (ARCHIVE_FATAL);
  55 }
  56 #else
  57 /* Don't compile this if we don't have zlib. */
  58
  59 struct private_data {
  60         z_stream         stream;
  61         int64_t          total_in;
  62         unsigned char   *compressed;
  63         size_t           compressed_buffer_size;
  64         unsigned long    crc;
  65 };
  66
  67 struct private_config {
  68         int              compression_level;
  69 };
  70
  71
  72 /*
  73  * Yuck.  zlib.h is not const-correct, so I need this one bit
  74  * of ugly hackery to convert a const * pointer to a non-const pointer.
  75  */
  76 #define SET_NEXT_IN(st,src)                                     \
  77         (st)->stream.next_in = (Bytef *)(uintptr_t)(const void *)(src)
  78
  79 static int      archive_compressor_gzip_finish(struct archive_write *);
  80 static int      archive_compressor_gzip_init(struct archive_write *);
  81 static int      archive_compressor_gzip_options(struct archive_write *,
  82                     const char *, const char *);
  83 static int      archive_compressor_gzip_write(struct archive_write *,
  84                     const void *, size_t);
  85 static int      drive_compressor(struct archive_write *, struct private_data *,
  86                     int finishing);
  87
  88
  89 /*
  90  * Allocate, initialize and return a archive object.
  91  */
  92 int
  93 archive_write_set_compression_gzip(struct archive *_a)
  94 {
  95         struct archive_write *a = (struct archive_write *)_a;
  96         struct private_config *config;
  97         __archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
  98             ARCHIVE_STATE_NEW, "archive_write_set_compression_gzip");
  99         config = malloc(sizeof(*config));
 100         if (config == NULL) {
 101                 archive_set_error(&a->archive, ENOMEM, "Out of memory");
 102                 return (ARCHIVE_FATAL);
 103         }
 104         a->compressor.config = config;
 105         a->compressor.finish = &archive_compressor_gzip_finish;
 106         config->compression_level = Z_DEFAULT_COMPRESSION;
 107         a->compressor.init = &archive_compressor_gzip_init;
 108         a->compressor.options = &archive_compressor_gzip_options;
 109         a->archive.compression_code = ARCHIVE_COMPRESSION_GZIP;
 110         a->archive.compression_name = "gzip";
 111         return (ARCHIVE_OK);
 112 }
 113
 114 /*
 115  * Setup callback.
 116  */
 117 static int
 118 archive_compressor_gzip_init(struct archive_write *a)
 119 {
 120         int ret;
 121         struct private_data *state;
 122         struct private_config *config;
 123         time_t t;
 124
 125         config = (struct private_config *)a->compressor.config;
 126
 127         if (a->client_opener != NULL) {
 128                 ret = (a->client_opener)(&a->archive, a->client_data);
 129                 if (ret != ARCHIVE_OK)
 130                         return (ret);
 131         }
 132
 133         /*
 134          * The next check is a temporary workaround until the gzip
 135          * code can be overhauled some.  The code should not require
 136          * that compressed_buffer_size == bytes_per_block.  Removing
 137          * this assumption will allow us to compress larger chunks at
 138          * a time, which should improve overall performance
 139          * marginally.  As a minor side-effect, such a cleanup would
 140          * allow us to support truly arbitrary block sizes.
 141          */
 142         if (a->bytes_per_block < 10) {
 143                 archive_set_error(&a->archive, EINVAL,
 144                     "GZip compressor requires a minimum 10 byte block size");
 145                 return (ARCHIVE_FATAL);
 146         }
 147
 148         state = (struct private_data *)malloc(sizeof(*state));
 149         if (state == NULL) {
 150                 archive_set_error(&a->archive, ENOMEM,
 151                     "Can't allocate data for compression");
 152                 return (ARCHIVE_FATAL);
 153         }
 154         memset(state, 0, sizeof(*state));
 155
 156         /*
 157          * See comment above.  We should set compressed_buffer_size to
 158          * max(bytes_per_block, 65536), but the code can't handle that yet.
 159          */
 160         state->compressed_buffer_size = a->bytes_per_block;
 161         state->compressed = (unsigned char *)malloc(state->compressed_buffer_size);
 162         state->crc = crc32(0L, NULL, 0);
 163
 164         if (state->compressed == NULL) {
 165                 archive_set_error(&a->archive, ENOMEM,
 166                     "Can't allocate data for compression buffer");
 167                 free(state);
 168                 return (ARCHIVE_FATAL);
 169         }
 170
 171         state->stream.next_out = state->compressed;
 172         state->stream.avail_out = state->compressed_buffer_size;
 173
 174         /* Prime output buffer with a gzip header. */
 175         t = time(NULL);
 176         state->compressed[0] = 0x1f; /* GZip signature bytes */
 177         state->compressed[1] = 0x8b;
 178         state->compressed[2] = 0x08; /* "Deflate" compression */
 179         state->compressed[3] = 0; /* No options */
 180         state->compressed[4] = (t)&0xff;  /* Timestamp */
 181         state->compressed[5] = (t>>8)&0xff;
 182         state->compressed[6] = (t>>16)&0xff;
 183         state->compressed[7] = (t>>24)&0xff;
 184         state->compressed[8] = 0; /* No deflate options */
 185         state->compressed[9] = 3; /* OS=Unix */
 186         state->stream.next_out += 10;
 187         state->stream.avail_out -= 10;
 188
 189         a->compressor.write = archive_compressor_gzip_write;
 190
 191         /* Initialize compression library. */
 192         ret = deflateInit2(&(state->stream),
 193             config->compression_level,
 194             Z_DEFLATED,
 195             -15 /* < 0 to suppress zlib header */,
 196             8,
 197             Z_DEFAULT_STRATEGY);
 198
 199         if (ret == Z_OK) {
 200                 a->compressor.data = state;
 201                 return (0);
 202         }
 203
 204         /* Library setup failed: clean up. */
 205         archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Internal error "
 206             "initializing compression library");
 207         free(state->compressed);
 208         free(state);
 209
 210         /* Override the error message if we know what really went wrong. */
 211         switch (ret) {
 212         case Z_STREAM_ERROR:
 213                 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
 214                     "Internal error initializing "
 215                     "compression library: invalid setup parameter");
 216                 break;
 217         case Z_MEM_ERROR:
 218                 archive_set_error(&a->archive, ENOMEM, "Internal error initializing "
 219                     "compression library");
 220                 break;
 221         case Z_VERSION_ERROR:
 222                 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
 223                     "Internal error initializing "
 224                     "compression library: invalid library version");
 225                 break;
 226         }
 227
 228         return (ARCHIVE_FATAL);
 229 }
 230
 231 /*
 232  * Set write options.
 233  */
 234 static int
 235 archive_compressor_gzip_options(struct archive_write *a, const char *key,
 236     const char *value)
 237 {
 238         struct private_config *config;
 239
 240         config = (struct private_config *)a->compressor.config;
 241         if (strcmp(key, "compression-level") == 0) {
 242                 if (value == NULL || !(value[0] >= '0' && value[0] <= '9') ||
 243                     value[1] != '\0')
 244                         return (ARCHIVE_WARN);
 245                 config->compression_level = value[0] - '0';
 246                 return (ARCHIVE_OK);
 247         }
 248
 249         return (ARCHIVE_WARN);
 250 }
 251
 252 /*
 253  * Write data to the compressed stream.
 254  */
 255 static int
 256 archive_compressor_gzip_write(struct archive_write *a, const void *buff,
 257     size_t length)
 258 {
 259         struct private_data *state;
 260         int ret;
 261
 262         state = (struct private_data *)a->compressor.data;
 263         if (a->client_writer == NULL) {
 264                 archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
 265                     "No write callback is registered?  "
 266                     "This is probably an internal programming error.");
 267                 return (ARCHIVE_FATAL);
 268         }
 269
 270         /* Update statistics */
 271         state->crc = crc32(state->crc, (const Bytef *)buff, length);
 272         state->total_in += length;
 273
 274         /* Compress input data to output buffer */
 275         SET_NEXT_IN(state, buff);
 276         state->stream.avail_in = length;
 277         if ((ret = drive_compressor(a, state, 0)) != ARCHIVE_OK)
 278                 return (ret);
 279
 280         a->archive.file_position += length;
 281         return (ARCHIVE_OK);
 282 }
 283
 284 /*
 285  * Finish the compression...
 286  */
 287 static int
 288 archive_compressor_gzip_finish(struct archive_write *a)
 289 {
 290         ssize_t block_length, target_block_length, bytes_written;
 291         int ret;
 292         struct private_data *state;
 293         unsigned tocopy;
 294         unsigned char trailer[8];
 295
 296         state = (struct private_data *)a->compressor.data;
 297         ret = 0;
 298         if (state != NULL) {
 299                 if (a->client_writer == NULL) {
 300                         archive_set_error(&a->archive,
 301                             ARCHIVE_ERRNO_PROGRAMMER,
 302                             "No write callback is registered?  "
 303                             "This is probably an internal programming error.");
 304                         ret = ARCHIVE_FATAL;
 305                         goto cleanup;
 306                 }
 307
 308                 /* By default, always pad the uncompressed data. */
 309                 if (a->pad_uncompressed) {
 310                         tocopy = a->bytes_per_block -
 311                             (state->total_in % a->bytes_per_block);
 312                         while (tocopy > 0 && tocopy < (unsigned)a->bytes_per_block) {
 313                                 SET_NEXT_IN(state, a->nulls);
 314                                 state->stream.avail_in = tocopy < a->null_length ?
 315                                     tocopy : a->null_length;
 316                                 state->crc = crc32(state->crc, a->nulls,
 317                                     state->stream.avail_in);
 318                                 state->total_in += state->stream.avail_in;
 319                                 tocopy -= state->stream.avail_in;
 320                                 ret = drive_compressor(a, state, 0);
 321                                 if (ret != ARCHIVE_OK)
 322                                         goto cleanup;
 323                         }
 324                 }
 325
 326                 /* Finish compression cycle */
 327                 if (((ret = drive_compressor(a, state, 1))) != ARCHIVE_OK)
 328                         goto cleanup;
 329
 330                 /* Build trailer: 4-byte CRC and 4-byte length. */
 331                 trailer[0] = (state->crc)&0xff;
 332                 trailer[1] = (state->crc >> 8)&0xff;
 333                 trailer[2] = (state->crc >> 16)&0xff;
 334                 trailer[3] = (state->crc >> 24)&0xff;
 335                 trailer[4] = (state->total_in)&0xff;
 336                 trailer[5] = (state->total_in >> 8)&0xff;
 337                 trailer[6] = (state->total_in >> 16)&0xff;
 338                 trailer[7] = (state->total_in >> 24)&0xff;
 339
 340                 /* Add trailer to current block. */
 341                 tocopy = 8;
 342                 if (tocopy > state->stream.avail_out)
 343                         tocopy = state->stream.avail_out;
 344                 memcpy(state->stream.next_out, trailer, tocopy);
 345                 state->stream.next_out += tocopy;
 346                 state->stream.avail_out -= tocopy;
 347
 348                 /* If it overflowed, flush and start a new block. */
 349                 if (tocopy < 8) {
 350                         bytes_written = (a->client_writer)(&a->archive, a->client_data,
 351                             state->compressed, state->compressed_buffer_size);
 352                         if (bytes_written <= 0) {
 353                                 ret = ARCHIVE_FATAL;
 354                                 goto cleanup;
 355                         }
 356                         a->archive.raw_position += bytes_written;
 357                         state->stream.next_out = state->compressed;
 358                         state->stream.avail_out = state->compressed_buffer_size;
 359                         memcpy(state->stream.next_out, trailer + tocopy, 8-tocopy);
 360                         state->stream.next_out += 8-tocopy;
 361                         state->stream.avail_out -= 8-tocopy;
 362                 }
 363
 364                 /* Optionally, pad the final compressed block. */
 365                 block_length = state->stream.next_out - state->compressed;
 366
 367                 /* Tricky calculation to determine size of last block. */
 368                 if (a->bytes_in_last_block <= 0)
 369                         /* Default or Zero: pad to full block */
 370                         target_block_length = a->bytes_per_block;
 371                 else
 372                         /* Round length to next multiple of bytes_in_last_block. */
 373                         target_block_length = a->bytes_in_last_block *
 374                             ( (block_length + a->bytes_in_last_block - 1) /
 375                                 a->bytes_in_last_block);
 376                 if (target_block_length > a->bytes_per_block)
 377                         target_block_length = a->bytes_per_block;
 378                 if (block_length < target_block_length) {
 379                         memset(state->stream.next_out, 0,
 380                             target_block_length - block_length);
 381                         block_length = target_block_length;
 382                 }
 383
 384                 /* Write the last block */
 385                 bytes_written = (a->client_writer)(&a->archive, a->client_data,
 386                     state->compressed, block_length);
 387                 if (bytes_written <= 0) {
 388                         ret = ARCHIVE_FATAL;
 389                         goto cleanup;
 390                 }
 391                 a->archive.raw_position += bytes_written;
 392
 393                 /* Cleanup: shut down compressor, release memory, etc. */
 394         cleanup:
 395                 switch (deflateEnd(&(state->stream))) {
 396                 case Z_OK:
 397                         break;
 398                 default:
 399                         archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
 400                             "Failed to clean up compressor");
 401                         ret = ARCHIVE_FATAL;
 402                 }
 403                 free(state->compressed);
 404                 free(state);
 405         }
 406         /* Clean up config area even if we never initialized. */
 407         free(a->compressor.config);
 408         a->compressor.config = NULL;
 409         return (ret);
 410 }
 411
 412 /*
 413  * Utility function to push input data through compressor,
 414  * writing full output blocks as necessary.
 415  *
 416  * Note that this handles both the regular write case (finishing ==
 417  * false) and the end-of-archive case (finishing == true).
 418  */
 419 static int
 420 drive_compressor(struct archive_write *a, struct private_data *state, int finishing)
 421 {
 422         ssize_t bytes_written;
 423         int ret;
 424
 425         for (;;) {
 426                 if (state->stream.avail_out == 0) {
 427                         bytes_written = (a->client_writer)(&a->archive,
 428                             a->client_data, state->compressed,
 429                             state->compressed_buffer_size);
 430                         if (bytes_written <= 0) {
 431                                 /* TODO: Handle this write failure */
 432                                 return (ARCHIVE_FATAL);
 433                         } else if ((size_t)bytes_written < state->compressed_buffer_size) {
 434                                 /* Short write: Move remaining to
 435                                  * front of block and keep filling */
 436                                 memmove(state->compressed,
 437                                     state->compressed + bytes_written,
 438                                     state->compressed_buffer_size - bytes_written);
 439                         }
 440                         a->archive.raw_position += bytes_written;
 441                         state->stream.next_out
 442                             = state->compressed +
 443                             state->compressed_buffer_size - bytes_written;
 444                         state->stream.avail_out = bytes_written;
 445                 }
 446
 447                 /* If there's nothing to do, we're done. */
 448                 if (!finishing && state->stream.avail_in == 0)
 449                         return (ARCHIVE_OK);
 450
 451                 ret = deflate(&(state->stream),
 452                     finishing ? Z_FINISH : Z_NO_FLUSH );
 453
 454                 switch (ret) {
 455                 case Z_OK:
 456                         /* In non-finishing case, check if compressor
 457                          * consumed everything */
 458                         if (!finishing && state->stream.avail_in == 0)
 459                                 return (ARCHIVE_OK);
 460                         /* In finishing case, this return always means
 461                          * there's more work */
 462                         break;
 463                 case Z_STREAM_END:
 464                         /* This return can only occur in finishing case. */
 465                         return (ARCHIVE_OK);
 466                 default:
 467                         /* Any other return value indicates an error. */
 468                         archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
 469                             "GZip compression failed:"
 470                             " deflate() call returned status %d",
 471                             ret);
 472                         return (ARCHIVE_FATAL);
 473                 }
 474         }
 475 }
 476
 477 #endif /* HAVE_ZLIB_H */