contrib/libarchive/libarchive/archive_write.c

   1 /*-
   2  * Copyright (c) 2003-2010 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 __FBSDID("$FreeBSD: head/lib/libarchive/archive_write.c 201099 2009-12-28 03:03:00Z kientzle $");
  28
  29 /*
  30  * This file contains the "essential" portions of the write API, that
  31  * is, stuff that will essentially always be used by any client that
  32  * actually needs to write an archive.  Optional pieces have been, as
  33  * far as possible, separated out into separate files to reduce
  34  * needlessly bloating statically-linked clients.
  35  */
  36
  37 #ifdef HAVE_SYS_WAIT_H
  38 #include <sys/wait.h>
  39 #endif
  40 #ifdef HAVE_ERRNO_H
  41 #include <errno.h>
  42 #endif
  43 #ifdef HAVE_LIMITS_H
  44 #include <limits.h>
  45 #endif
  46 #include <stdio.h>
  47 #ifdef HAVE_STDLIB_H
  48 #include <stdlib.h>
  49 #endif
  50 #ifdef HAVE_STRING_H
  51 #include <string.h>
  52 #endif
  53 #include <time.h>
  54 #ifdef HAVE_UNISTD_H
  55 #include <unistd.h>
  56 #endif
  57
  58 #include "archive.h"
  59 #include "archive_entry.h"
  60 #include "archive_private.h"
  61 #include "archive_write_private.h"
  62
  63 static struct archive_vtable *archive_write_vtable(void);
  64
  65 static int      _archive_filter_code(struct archive *, int);
  66 static const char *_archive_filter_name(struct archive *, int);
  67 static int64_t  _archive_filter_bytes(struct archive *, int);
  68 static int  _archive_write_filter_count(struct archive *);
  69 static int      _archive_write_close(struct archive *);
  70 static int      _archive_write_free(struct archive *);
  71 static int      _archive_write_header(struct archive *, struct archive_entry *);
  72 static int      _archive_write_finish_entry(struct archive *);
  73 static ssize_t  _archive_write_data(struct archive *, const void *, size_t);
  74
  75 struct archive_none {
  76         size_t buffer_size;
  77         size_t avail;
  78         char *buffer;
  79         char *next;
  80 };
  81
  82 static struct archive_vtable *
  83 archive_write_vtable(void)
  84 {
  85         static struct archive_vtable av;
  86         static int inited = 0;
  87
  88         if (!inited) {
  89                 av.archive_close = _archive_write_close;
  90                 av.archive_filter_bytes = _archive_filter_bytes;
  91                 av.archive_filter_code = _archive_filter_code;
  92                 av.archive_filter_name = _archive_filter_name;
  93                 av.archive_filter_count = _archive_write_filter_count;
  94                 av.archive_free = _archive_write_free;
  95                 av.archive_write_header = _archive_write_header;
  96                 av.archive_write_finish_entry = _archive_write_finish_entry;
  97                 av.archive_write_data = _archive_write_data;
  98                 inited = 1;
  99         }
 100         return (&av);
 101 }
 102
 103 /*
 104  * Allocate, initialize and return an archive object.
 105  */
 106 struct archive *
 107 archive_write_new(void)
 108 {
 109         struct archive_write *a;
 110         unsigned char *nulls;
 111
 112         a = (struct archive_write *)malloc(sizeof(*a));
 113         if (a == NULL)
 114                 return (NULL);
 115         memset(a, 0, sizeof(*a));
 116         a->archive.magic = ARCHIVE_WRITE_MAGIC;
 117         a->archive.state = ARCHIVE_STATE_NEW;
 118         a->archive.vtable = archive_write_vtable();
 119         /*
 120          * The value 10240 here matches the traditional tar default,
 121          * but is otherwise arbitrary.
 122          * TODO: Set the default block size from the format selected.
 123          */
 124         a->bytes_per_block = 10240;
 125         a->bytes_in_last_block = -1;    /* Default */
 126
 127         /* Initialize a block of nulls for padding purposes. */
 128         a->null_length = 1024;
 129         nulls = (unsigned char *)malloc(a->null_length);
 130         if (nulls == NULL) {
 131                 free(a);
 132                 return (NULL);
 133         }
 134         memset(nulls, 0, a->null_length);
 135         a->nulls = nulls;
 136         return (&a->archive);
 137 }
 138
 139 /*
 140  * Set the block size.  Returns 0 if successful.
 141  */
 142 int
 143 archive_write_set_bytes_per_block(struct archive *_a, int bytes_per_block)
 144 {
 145         struct archive_write *a = (struct archive_write *)_a;
 146         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 147             ARCHIVE_STATE_NEW, "archive_write_set_bytes_per_block");
 148         a->bytes_per_block = bytes_per_block;
 149         return (ARCHIVE_OK);
 150 }
 151
 152 /*
 153  * Get the current block size.  -1 if it has never been set.
 154  */
 155 int
 156 archive_write_get_bytes_per_block(struct archive *_a)
 157 {
 158         struct archive_write *a = (struct archive_write *)_a;
 159         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 160             ARCHIVE_STATE_ANY, "archive_write_get_bytes_per_block");
 161         return (a->bytes_per_block);
 162 }
 163
 164 /*
 165  * Set the size for the last block.
 166  * Returns 0 if successful.
 167  */
 168 int
 169 archive_write_set_bytes_in_last_block(struct archive *_a, int bytes)
 170 {
 171         struct archive_write *a = (struct archive_write *)_a;
 172         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 173             ARCHIVE_STATE_ANY, "archive_write_set_bytes_in_last_block");
 174         a->bytes_in_last_block = bytes;
 175         return (ARCHIVE_OK);
 176 }
 177
 178 /*
 179  * Return the value set above.  -1 indicates it has not been set.
 180  */
 181 int
 182 archive_write_get_bytes_in_last_block(struct archive *_a)
 183 {
 184         struct archive_write *a = (struct archive_write *)_a;
 185         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 186             ARCHIVE_STATE_ANY, "archive_write_get_bytes_in_last_block");
 187         return (a->bytes_in_last_block);
 188 }
 189
 190 /*
 191  * dev/ino of a file to be rejected.  Used to prevent adding
 192  * an archive to itself recursively.
 193  */
 194 int
 195 archive_write_set_skip_file(struct archive *_a, int64_t d, int64_t i)
 196 {
 197         struct archive_write *a = (struct archive_write *)_a;
 198         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 199             ARCHIVE_STATE_ANY, "archive_write_set_skip_file");
 200         a->skip_file_set = 1;
 201         a->skip_file_dev = d;
 202         a->skip_file_ino = i;
 203         return (ARCHIVE_OK);
 204 }
 205
 206 /*
 207  * Allocate and return the next filter structure.
 208  */
 209 struct archive_write_filter *
 210 __archive_write_allocate_filter(struct archive *_a)
 211 {
 212         struct archive_write *a = (struct archive_write *)_a;
 213         struct archive_write_filter *f;
 214
 215         f = calloc(1, sizeof(*f));
 216         f->archive = _a;
 217         if (a->filter_first == NULL)
 218                 a->filter_first = f;
 219         else
 220                 a->filter_last->next_filter = f;
 221         a->filter_last = f;
 222         return f;
 223 }
 224
 225 /*
 226  * Write data to a particular filter.
 227  */
 228 int
 229 __archive_write_filter(struct archive_write_filter *f,
 230     const void *buff, size_t length)
 231 {
 232         int r;
 233         if (length == 0)
 234                 return(ARCHIVE_OK);
 235         r = (f->write)(f, buff, length);
 236         f->bytes_written += length;
 237         return (r);
 238 }
 239
 240 /*
 241  * Open a filter.
 242  */
 243 int
 244 __archive_write_open_filter(struct archive_write_filter *f)
 245 {
 246         if (f->open == NULL)
 247                 return (ARCHIVE_OK);
 248         return (f->open)(f);
 249 }
 250
 251 /*
 252  * Close a filter.
 253  */
 254 int
 255 __archive_write_close_filter(struct archive_write_filter *f)
 256 {
 257         if (f->close != NULL)
 258                 return (f->close)(f);
 259         if (f->next_filter != NULL)
 260                 return (__archive_write_close_filter(f->next_filter));
 261         return (ARCHIVE_OK);
 262 }
 263
 264 int
 265 __archive_write_output(struct archive_write *a, const void *buff, size_t length)
 266 {
 267         return (__archive_write_filter(a->filter_first, buff, length));
 268 }
 269
 270 int
 271 __archive_write_nulls(struct archive_write *a, size_t length)
 272 {
 273         if (length == 0)
 274                 return (ARCHIVE_OK);
 275
 276         while (length > 0) {
 277                 size_t to_write = length < a->null_length ? length : a->null_length;
 278                 int r = __archive_write_output(a, a->nulls, to_write);
 279                 if (r < ARCHIVE_OK)
 280                         return (r);
 281                 length -= to_write;
 282         }
 283         return (ARCHIVE_OK);
 284 }
 285
 286 static int
 287 archive_write_client_open(struct archive_write_filter *f)
 288 {
 289         struct archive_write *a = (struct archive_write *)f->archive;
 290         struct archive_none *state;
 291         void *buffer;
 292         size_t buffer_size;
 293
 294         f->bytes_per_block = archive_write_get_bytes_per_block(f->archive);
 295         f->bytes_in_last_block =
 296             archive_write_get_bytes_in_last_block(f->archive);
 297         buffer_size = f->bytes_per_block;
 298
 299         state = (struct archive_none *)calloc(1, sizeof(*state));
 300         buffer = (char *)malloc(buffer_size);
 301         if (state == NULL || buffer == NULL) {
 302                 free(state);
 303                 free(buffer);
 304                 archive_set_error(f->archive, ENOMEM,
 305                     "Can't allocate data for output buffering");
 306                 return (ARCHIVE_FATAL);
 307         }
 308
 309         state->buffer_size = buffer_size;
 310         state->buffer = buffer;
 311         state->next = state->buffer;
 312         state->avail = state->buffer_size;
 313         f->data = state;
 314
 315         if (a->client_opener == NULL)
 316                 return (ARCHIVE_OK);
 317         return (a->client_opener(f->archive, a->client_data));
 318 }
 319
 320 static int
 321 archive_write_client_write(struct archive_write_filter *f,
 322     const void *_buff, size_t length)
 323 {
 324         struct archive_write *a = (struct archive_write *)f->archive;
 325         struct archive_none *state = (struct archive_none *)f->data;
 326         const char *buff = (const char *)_buff;
 327         ssize_t remaining, to_copy;
 328         ssize_t bytes_written;
 329
 330         remaining = length;
 331
 332         /*
 333          * If there is no buffer for blocking, just pass the data
 334          * straight through to the client write callback.  In
 335          * particular, this supports "no write delay" operation for
 336          * special applications.  Just set the block size to zero.
 337          */
 338         if (state->buffer_size == 0) {
 339                 while (remaining > 0) {
 340                         bytes_written = (a->client_writer)(&a->archive,
 341                             a->client_data, buff, remaining);
 342                         if (bytes_written <= 0)
 343                                 return (ARCHIVE_FATAL);
 344                         remaining -= bytes_written;
 345                         buff += bytes_written;
 346                 }
 347                 return (ARCHIVE_OK);
 348         }
 349
 350         /* If the copy buffer isn't empty, try to fill it. */
 351         if (state->avail < state->buffer_size) {
 352                 /* If buffer is not empty... */
 353                 /* ... copy data into buffer ... */
 354                 to_copy = ((size_t)remaining > state->avail) ?
 355                         state->avail : (size_t)remaining;
 356                 memcpy(state->next, buff, to_copy);
 357                 state->next += to_copy;
 358                 state->avail -= to_copy;
 359                 buff += to_copy;
 360                 remaining -= to_copy;
 361                 /* ... if it's full, write it out. */
 362                 if (state->avail == 0) {
 363                         char *p = state->buffer;
 364                         size_t to_write = state->buffer_size;
 365                         while (to_write > 0) {
 366                                 bytes_written = (a->client_writer)(&a->archive,
 367                                     a->client_data, p, to_write);
 368                                 if (bytes_written <= 0)
 369                                         return (ARCHIVE_FATAL);
 370                                 if ((size_t)bytes_written > to_write) {
 371                                         archive_set_error(&(a->archive),
 372                                             -1, "write overrun");
 373                                         return (ARCHIVE_FATAL);
 374                                 }
 375                                 p += bytes_written;
 376                                 to_write -= bytes_written;
 377                         }
 378                         state->next = state->buffer;
 379                         state->avail = state->buffer_size;
 380                 }
 381         }
 382
 383         while ((size_t)remaining > state->buffer_size) {
 384                 /* Write out full blocks directly to client. */
 385                 bytes_written = (a->client_writer)(&a->archive,
 386                     a->client_data, buff, state->buffer_size);
 387                 if (bytes_written <= 0)
 388                         return (ARCHIVE_FATAL);
 389                 buff += bytes_written;
 390                 remaining -= bytes_written;
 391         }
 392
 393         if (remaining > 0) {
 394                 /* Copy last bit into copy buffer. */
 395                 memcpy(state->next, buff, remaining);
 396                 state->next += remaining;
 397                 state->avail -= remaining;
 398         }
 399         return (ARCHIVE_OK);
 400 }
 401
 402 static int
 403 archive_write_client_close(struct archive_write_filter *f)
 404 {
 405         struct archive_write *a = (struct archive_write *)f->archive;
 406         struct archive_none *state = (struct archive_none *)f->data;
 407         ssize_t block_length;
 408         ssize_t target_block_length;
 409         ssize_t bytes_written;
 410         int ret = ARCHIVE_OK;
 411
 412         /* If there's pending data, pad and write the last block */
 413         if (state->next != state->buffer) {
 414                 block_length = state->buffer_size - state->avail;
 415
 416                 /* Tricky calculation to determine size of last block */
 417                 if (a->bytes_in_last_block <= 0)
 418                         /* Default or Zero: pad to full block */
 419                         target_block_length = a->bytes_per_block;
 420                 else
 421                         /* Round to next multiple of bytes_in_last_block. */
 422                         target_block_length = a->bytes_in_last_block *
 423                             ( (block_length + a->bytes_in_last_block - 1) /
 424                                 a->bytes_in_last_block);
 425                 if (target_block_length > a->bytes_per_block)
 426                         target_block_length = a->bytes_per_block;
 427                 if (block_length < target_block_length) {
 428                         memset(state->next, 0,
 429                             target_block_length - block_length);
 430                         block_length = target_block_length;
 431                 }
 432                 bytes_written = (a->client_writer)(&a->archive,
 433                     a->client_data, state->buffer, block_length);
 434                 ret = bytes_written <= 0 ? ARCHIVE_FATAL : ARCHIVE_OK;
 435         }
 436         if (a->client_closer)
 437                 (*a->client_closer)(&a->archive, a->client_data);
 438         free(state->buffer);
 439         free(state);
 440         a->client_data = NULL;
 441         return (ret);
 442 }
 443
 444 /*
 445  * Open the archive using the current settings.
 446  */
 447 int
 448 archive_write_open(struct archive *_a, void *client_data,
 449     archive_open_callback *opener, archive_write_callback *writer,
 450     archive_close_callback *closer)
 451 {
 452         struct archive_write *a = (struct archive_write *)_a;
 453         struct archive_write_filter *client_filter;
 454         int ret, r1;
 455
 456         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 457             ARCHIVE_STATE_NEW, "archive_write_open");
 458         archive_clear_error(&a->archive);
 459
 460         a->client_writer = writer;
 461         a->client_opener = opener;
 462         a->client_closer = closer;
 463         a->client_data = client_data;
 464
 465         client_filter = __archive_write_allocate_filter(_a);
 466         client_filter->open = archive_write_client_open;
 467         client_filter->write = archive_write_client_write;
 468         client_filter->close = archive_write_client_close;
 469
 470         ret = __archive_write_open_filter(a->filter_first);
 471         if (ret < ARCHIVE_WARN) {
 472                 r1 = __archive_write_close_filter(a->filter_first);
 473                 return (r1 < ret ? r1 : ret);
 474         }
 475
 476         a->archive.state = ARCHIVE_STATE_HEADER;
 477         if (a->format_init)
 478                 ret = (a->format_init)(a);
 479         return (ret);
 480 }
 481
 482 /*
 483  * Close out the archive.
 484  */
 485 static int
 486 _archive_write_close(struct archive *_a)
 487 {
 488         struct archive_write *a = (struct archive_write *)_a;
 489         int r = ARCHIVE_OK, r1 = ARCHIVE_OK;
 490
 491         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 492             ARCHIVE_STATE_ANY | ARCHIVE_STATE_FATAL,
 493             "archive_write_close");
 494         if (a->archive.state == ARCHIVE_STATE_NEW
 495             || a->archive.state == ARCHIVE_STATE_CLOSED)
 496                 return (ARCHIVE_OK); /* Okay to close() when not open. */
 497
 498         archive_clear_error(&a->archive);
 499
 500         /* Finish the last entry. */
 501         if (a->archive.state == ARCHIVE_STATE_DATA)
 502                 r = ((a->format_finish_entry)(a));
 503
 504         /* Finish off the archive. */
 505         /* TODO: have format closers invoke compression close. */
 506         if (a->format_close != NULL) {
 507                 r1 = (a->format_close)(a);
 508                 if (r1 < r)
 509                         r = r1;
 510         }
 511
 512         /* Finish the compression and close the stream. */
 513         r1 = __archive_write_close_filter(a->filter_first);
 514         if (r1 < r)
 515                 r = r1;
 516
 517         if (a->archive.state != ARCHIVE_STATE_FATAL)
 518                 a->archive.state = ARCHIVE_STATE_CLOSED;
 519         return (r);
 520 }
 521
 522 static int
 523 _archive_write_filter_count(struct archive *_a)
 524 {
 525         struct archive_write *a = (struct archive_write *)_a;
 526         struct archive_write_filter *p = a->filter_first;
 527         int count = 0;
 528         while(p) {
 529                 count++;
 530                 p = p->next_filter;
 531         }
 532         return count;
 533 }
 534
 535 void
 536 __archive_write_filters_free(struct archive *_a)
 537 {
 538         struct archive_write *a = (struct archive_write *)_a;
 539         int r = ARCHIVE_OK, r1;
 540
 541         while (a->filter_first != NULL) {
 542                 struct archive_write_filter *next
 543                     = a->filter_first->next_filter;
 544                 if (a->filter_first->free != NULL) {
 545                         r1 = (*a->filter_first->free)(a->filter_first);
 546                         if (r > r1)
 547                                 r = r1;
 548                 }
 549                 free(a->filter_first);
 550                 a->filter_first = next;
 551         }
 552         a->filter_last = NULL;
 553 }
 554
 555 /*
 556  * Destroy the archive structure.
 557  *
 558  * Be careful: user might just call write_new and then write_free.
 559  * Don't assume we actually wrote anything or performed any non-trivial
 560  * initialization.
 561  */
 562 static int
 563 _archive_write_free(struct archive *_a)
 564 {
 565         struct archive_write *a = (struct archive_write *)_a;
 566         int r = ARCHIVE_OK, r1;
 567
 568         if (_a == NULL)
 569                 return (ARCHIVE_OK);
 570         /* It is okay to call free() in state FATAL. */
 571         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 572             ARCHIVE_STATE_ANY | ARCHIVE_STATE_FATAL, "archive_write_free");
 573         if (a->archive.state != ARCHIVE_STATE_FATAL)
 574                 r = archive_write_close(&a->archive);
 575
 576         /* Release format resources. */
 577         if (a->format_free != NULL) {
 578                 r1 = (a->format_free)(a);
 579                 if (r1 < r)
 580                         r = r1;
 581         }
 582
 583         __archive_write_filters_free(_a);
 584
 585         /* Release various dynamic buffers. */
 586         free((void *)(uintptr_t)(const void *)a->nulls);
 587         archive_string_free(&a->archive.error_string);
 588         a->archive.magic = 0;
 589         __archive_clean(&a->archive);
 590         free(a);
 591         return (r);
 592 }
 593
 594 /*
 595  * Write the appropriate header.
 596  */
 597 static int
 598 _archive_write_header(struct archive *_a, struct archive_entry *entry)
 599 {
 600         struct archive_write *a = (struct archive_write *)_a;
 601         int ret, r2;
 602
 603         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 604             ARCHIVE_STATE_DATA | ARCHIVE_STATE_HEADER, "archive_write_header");
 605         archive_clear_error(&a->archive);
 606
 607         if (a->format_write_header == NULL) {
 608                 archive_set_error(&(a->archive), -1,
 609                     "Format must be set before you can write to an archive.");
 610                 a->archive.state = ARCHIVE_STATE_FATAL;
 611                 return (ARCHIVE_FATAL);
 612         }
 613
 614         /* In particular, "retry" and "fatal" get returned immediately. */
 615         ret = archive_write_finish_entry(&a->archive);
 616         if (ret == ARCHIVE_FATAL) {
 617                 a->archive.state = ARCHIVE_STATE_FATAL;
 618                 return (ARCHIVE_FATAL);
 619         }
 620         if (ret < ARCHIVE_OK && ret != ARCHIVE_WARN)
 621                 return (ret);
 622
 623         if (a->skip_file_set &&
 624             archive_entry_dev_is_set(entry) &&
 625             archive_entry_ino_is_set(entry) &&
 626             archive_entry_dev(entry) == a->skip_file_dev &&
 627             archive_entry_ino64(entry) == a->skip_file_ino) {
 628                 archive_set_error(&a->archive, 0,
 629                     "Can't add archive to itself");
 630                 return (ARCHIVE_FAILED);
 631         }
 632
 633         /* Format and write header. */
 634         r2 = ((a->format_write_header)(a, entry));
 635         if (r2 == ARCHIVE_FATAL) {
 636                 a->archive.state = ARCHIVE_STATE_FATAL;
 637                 return (ARCHIVE_FATAL);
 638         }
 639         if (r2 < ret)
 640                 ret = r2;
 641
 642         a->archive.state = ARCHIVE_STATE_DATA;
 643         return (ret);
 644 }
 645
 646 static int
 647 _archive_write_finish_entry(struct archive *_a)
 648 {
 649         struct archive_write *a = (struct archive_write *)_a;
 650         int ret = ARCHIVE_OK;
 651
 652         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 653             ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA,
 654             "archive_write_finish_entry");
 655         if (a->archive.state & ARCHIVE_STATE_DATA)
 656                 ret = (a->format_finish_entry)(a);
 657         a->archive.state = ARCHIVE_STATE_HEADER;
 658         return (ret);
 659 }
 660
 661 /*
 662  * Note that the compressor is responsible for blocking.
 663  */
 664 static ssize_t
 665 _archive_write_data(struct archive *_a, const void *buff, size_t s)
 666 {
 667         struct archive_write *a = (struct archive_write *)_a;
 668         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 669             ARCHIVE_STATE_DATA, "archive_write_data");
 670         archive_clear_error(&a->archive);
 671         return ((a->format_write_data)(a, buff, s));
 672 }
 673
 674 static struct archive_write_filter *
 675 filter_lookup(struct archive *_a, int n)
 676 {
 677         struct archive_write *a = (struct archive_write *)_a;
 678         struct archive_write_filter *f = a->filter_first;
 679         if (n == -1)
 680                 return a->filter_last;
 681         if (n < 0)
 682                 return NULL;
 683         while (n > 0 && f != NULL) {
 684                 f = f->next_filter;
 685                 --n;
 686         }
 687         return f;
 688 }
 689
 690 static int
 691 _archive_filter_code(struct archive *_a, int n)
 692 {
 693         struct archive_write_filter *f = filter_lookup(_a, n);
 694         return f == NULL ? -1 : f->code;
 695 }
 696
 697 static const char *
 698 _archive_filter_name(struct archive *_a, int n)
 699 {
 700         struct archive_write_filter *f = filter_lookup(_a, n);
 701         return f == NULL ? NULL : f->name;
 702 }
 703
 704 static int64_t
 705 _archive_filter_bytes(struct archive *_a, int n)
 706 {
 707         struct archive_write_filter *f = filter_lookup(_a, n);
 708         return f == NULL ? -1 : f->bytes_written;
 709 }