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("$FreeBSD$");
  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 *)calloc(1, sizeof(*a));
 113         if (a == NULL)
 114                 return (NULL);
 115         a->archive.magic = ARCHIVE_WRITE_MAGIC;
 116         a->archive.state = ARCHIVE_STATE_NEW;
 117         a->archive.vtable = archive_write_vtable();
 118         /*
 119          * The value 10240 here matches the traditional tar default,
 120          * but is otherwise arbitrary.
 121          * TODO: Set the default block size from the format selected.
 122          */
 123         a->bytes_per_block = 10240;
 124         a->bytes_in_last_block = -1;    /* Default */
 125
 126         /* Initialize a block of nulls for padding purposes. */
 127         a->null_length = 1024;
 128         nulls = (unsigned char *)calloc(1, a->null_length);
 129         if (nulls == NULL) {
 130                 free(a);
 131                 return (NULL);
 132         }
 133         a->nulls = nulls;
 134         return (&a->archive);
 135 }
 136
 137 /*
 138  * Set the block size.  Returns 0 if successful.
 139  */
 140 int
 141 archive_write_set_bytes_per_block(struct archive *_a, int bytes_per_block)
 142 {
 143         struct archive_write *a = (struct archive_write *)_a;
 144         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 145             ARCHIVE_STATE_NEW, "archive_write_set_bytes_per_block");
 146         a->bytes_per_block = bytes_per_block;
 147         return (ARCHIVE_OK);
 148 }
 149
 150 /*
 151  * Get the current block size.  -1 if it has never been set.
 152  */
 153 int
 154 archive_write_get_bytes_per_block(struct archive *_a)
 155 {
 156         struct archive_write *a = (struct archive_write *)_a;
 157         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 158             ARCHIVE_STATE_ANY, "archive_write_get_bytes_per_block");
 159         return (a->bytes_per_block);
 160 }
 161
 162 /*
 163  * Set the size for the last block.
 164  * Returns 0 if successful.
 165  */
 166 int
 167 archive_write_set_bytes_in_last_block(struct archive *_a, int bytes)
 168 {
 169         struct archive_write *a = (struct archive_write *)_a;
 170         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 171             ARCHIVE_STATE_ANY, "archive_write_set_bytes_in_last_block");
 172         a->bytes_in_last_block = bytes;
 173         return (ARCHIVE_OK);
 174 }
 175
 176 /*
 177  * Return the value set above.  -1 indicates it has not been set.
 178  */
 179 int
 180 archive_write_get_bytes_in_last_block(struct archive *_a)
 181 {
 182         struct archive_write *a = (struct archive_write *)_a;
 183         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 184             ARCHIVE_STATE_ANY, "archive_write_get_bytes_in_last_block");
 185         return (a->bytes_in_last_block);
 186 }
 187
 188 /*
 189  * dev/ino of a file to be rejected.  Used to prevent adding
 190  * an archive to itself recursively.
 191  */
 192 int
 193 archive_write_set_skip_file(struct archive *_a, int64_t d, int64_t i)
 194 {
 195         struct archive_write *a = (struct archive_write *)_a;
 196         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 197             ARCHIVE_STATE_ANY, "archive_write_set_skip_file");
 198         a->skip_file_set = 1;
 199         a->skip_file_dev = d;
 200         a->skip_file_ino = i;
 201         return (ARCHIVE_OK);
 202 }
 203
 204 /*
 205  * Allocate and return the next filter structure.
 206  */
 207 struct archive_write_filter *
 208 __archive_write_allocate_filter(struct archive *_a)
 209 {
 210         struct archive_write *a = (struct archive_write *)_a;
 211         struct archive_write_filter *f;
 212
 213         f = calloc(1, sizeof(*f));
 214         f->archive = _a;
 215         if (a->filter_first == NULL)
 216                 a->filter_first = f;
 217         else
 218                 a->filter_last->next_filter = f;
 219         a->filter_last = f;
 220         return f;
 221 }
 222
 223 /*
 224  * Write data to a particular filter.
 225  */
 226 int
 227 __archive_write_filter(struct archive_write_filter *f,
 228     const void *buff, size_t length)
 229 {
 230         int r;
 231         if (length == 0)
 232                 return(ARCHIVE_OK);
 233         if (f->write == NULL)
 234                 /* If unset, a fatal error has already ocuured, so this filter
 235                  * didn't open. We cannot write anything. */
 236                 return(ARCHIVE_FATAL);
 237         r = (f->write)(f, buff, length);
 238         f->bytes_written += length;
 239         return (r);
 240 }
 241
 242 /*
 243  * Open a filter.
 244  */
 245 int
 246 __archive_write_open_filter(struct archive_write_filter *f)
 247 {
 248         if (f->open == NULL)
 249                 return (ARCHIVE_OK);
 250         return (f->open)(f);
 251 }
 252
 253 /*
 254  * Close a filter.
 255  */
 256 int
 257 __archive_write_close_filter(struct archive_write_filter *f)
 258 {
 259         if (f->close != NULL)
 260                 return (f->close)(f);
 261         if (f->next_filter != NULL)
 262                 return (__archive_write_close_filter(f->next_filter));
 263         return (ARCHIVE_OK);
 264 }
 265
 266 int
 267 __archive_write_output(struct archive_write *a, const void *buff, size_t length)
 268 {
 269         return (__archive_write_filter(a->filter_first, buff, length));
 270 }
 271
 272 int
 273 __archive_write_nulls(struct archive_write *a, size_t length)
 274 {
 275         if (length == 0)
 276                 return (ARCHIVE_OK);
 277
 278         while (length > 0) {
 279                 size_t to_write = length < a->null_length ? length : a->null_length;
 280                 int r = __archive_write_output(a, a->nulls, to_write);
 281                 if (r < ARCHIVE_OK)
 282                         return (r);
 283                 length -= to_write;
 284         }
 285         return (ARCHIVE_OK);
 286 }
 287
 288 static int
 289 archive_write_client_open(struct archive_write_filter *f)
 290 {
 291         struct archive_write *a = (struct archive_write *)f->archive;
 292         struct archive_none *state;
 293         void *buffer;
 294         size_t buffer_size;
 295
 296         f->bytes_per_block = archive_write_get_bytes_per_block(f->archive);
 297         f->bytes_in_last_block =
 298             archive_write_get_bytes_in_last_block(f->archive);
 299         buffer_size = f->bytes_per_block;
 300
 301         state = (struct archive_none *)calloc(1, sizeof(*state));
 302         buffer = (char *)malloc(buffer_size);
 303         if (state == NULL || buffer == NULL) {
 304                 free(state);
 305                 free(buffer);
 306                 archive_set_error(f->archive, ENOMEM,
 307                     "Can't allocate data for output buffering");
 308                 return (ARCHIVE_FATAL);
 309         }
 310
 311         state->buffer_size = buffer_size;
 312         state->buffer = buffer;
 313         state->next = state->buffer;
 314         state->avail = state->buffer_size;
 315         f->data = state;
 316
 317         if (a->client_opener == NULL)
 318                 return (ARCHIVE_OK);
 319         return (a->client_opener(f->archive, a->client_data));
 320 }
 321
 322 static int
 323 archive_write_client_write(struct archive_write_filter *f,
 324     const void *_buff, size_t length)
 325 {
 326         struct archive_write *a = (struct archive_write *)f->archive;
 327         struct archive_none *state = (struct archive_none *)f->data;
 328         const char *buff = (const char *)_buff;
 329         ssize_t remaining, to_copy;
 330         ssize_t bytes_written;
 331
 332         remaining = length;
 333
 334         /*
 335          * If there is no buffer for blocking, just pass the data
 336          * straight through to the client write callback.  In
 337          * particular, this supports "no write delay" operation for
 338          * special applications.  Just set the block size to zero.
 339          */
 340         if (state->buffer_size == 0) {
 341                 while (remaining > 0) {
 342                         bytes_written = (a->client_writer)(&a->archive,
 343                             a->client_data, buff, remaining);
 344                         if (bytes_written <= 0)
 345                                 return (ARCHIVE_FATAL);
 346                         remaining -= bytes_written;
 347                         buff += bytes_written;
 348                 }
 349                 return (ARCHIVE_OK);
 350         }
 351
 352         /* If the copy buffer isn't empty, try to fill it. */
 353         if (state->avail < state->buffer_size) {
 354                 /* If buffer is not empty... */
 355                 /* ... copy data into buffer ... */
 356                 to_copy = ((size_t)remaining > state->avail) ?
 357                         state->avail : (size_t)remaining;
 358                 memcpy(state->next, buff, to_copy);
 359                 state->next += to_copy;
 360                 state->avail -= to_copy;
 361                 buff += to_copy;
 362                 remaining -= to_copy;
 363                 /* ... if it's full, write it out. */
 364                 if (state->avail == 0) {
 365                         char *p = state->buffer;
 366                         size_t to_write = state->buffer_size;
 367                         while (to_write > 0) {
 368                                 bytes_written = (a->client_writer)(&a->archive,
 369                                     a->client_data, p, to_write);
 370                                 if (bytes_written <= 0)
 371                                         return (ARCHIVE_FATAL);
 372                                 if ((size_t)bytes_written > to_write) {
 373                                         archive_set_error(&(a->archive),
 374                                             -1, "write overrun");
 375                                         return (ARCHIVE_FATAL);
 376                                 }
 377                                 p += bytes_written;
 378                                 to_write -= bytes_written;
 379                         }
 380                         state->next = state->buffer;
 381                         state->avail = state->buffer_size;
 382                 }
 383         }
 384
 385         while ((size_t)remaining >= state->buffer_size) {
 386                 /* Write out full blocks directly to client. */
 387                 bytes_written = (a->client_writer)(&a->archive,
 388                     a->client_data, buff, state->buffer_size);
 389                 if (bytes_written <= 0)
 390                         return (ARCHIVE_FATAL);
 391                 buff += bytes_written;
 392                 remaining -= bytes_written;
 393         }
 394
 395         if (remaining > 0) {
 396                 /* Copy last bit into copy buffer. */
 397                 memcpy(state->next, buff, remaining);
 398                 state->next += remaining;
 399                 state->avail -= remaining;
 400         }
 401         return (ARCHIVE_OK);
 402 }
 403
 404 static int
 405 archive_write_client_close(struct archive_write_filter *f)
 406 {
 407         struct archive_write *a = (struct archive_write *)f->archive;
 408         struct archive_none *state = (struct archive_none *)f->data;
 409         ssize_t block_length;
 410         ssize_t target_block_length;
 411         ssize_t bytes_written;
 412         int ret = ARCHIVE_OK;
 413
 414         /* If there's pending data, pad and write the last block */
 415         if (state->next != state->buffer) {
 416                 block_length = state->buffer_size - state->avail;
 417
 418                 /* Tricky calculation to determine size of last block */
 419                 if (a->bytes_in_last_block <= 0)
 420                         /* Default or Zero: pad to full block */
 421                         target_block_length = a->bytes_per_block;
 422                 else
 423                         /* Round to next multiple of bytes_in_last_block. */
 424                         target_block_length = a->bytes_in_last_block *
 425                             ( (block_length + a->bytes_in_last_block - 1) /
 426                                 a->bytes_in_last_block);
 427                 if (target_block_length > a->bytes_per_block)
 428                         target_block_length = a->bytes_per_block;
 429                 if (block_length < target_block_length) {
 430                         memset(state->next, 0,
 431                             target_block_length - block_length);
 432                         block_length = target_block_length;
 433                 }
 434                 bytes_written = (a->client_writer)(&a->archive,
 435                     a->client_data, state->buffer, block_length);
 436                 ret = bytes_written <= 0 ? ARCHIVE_FATAL : ARCHIVE_OK;
 437         }
 438         if (a->client_closer)
 439                 (*a->client_closer)(&a->archive, a->client_data);
 440         free(state->buffer);
 441         free(state);
 442         /* Clear the close handler myself not to be called again. */
 443         f->close = NULL;
 444         a->client_data = NULL;
 445         /* Clear passphrase. */
 446         if (a->passphrase != NULL) {
 447                 memset(a->passphrase, 0, strlen(a->passphrase));
 448                 free(a->passphrase);
 449                 a->passphrase = NULL;
 450         }
 451         return (ret);
 452 }
 453
 454 /*
 455  * Open the archive using the current settings.
 456  */
 457 int
 458 archive_write_open(struct archive *_a, void *client_data,
 459     archive_open_callback *opener, archive_write_callback *writer,
 460     archive_close_callback *closer)
 461 {
 462         struct archive_write *a = (struct archive_write *)_a;
 463         struct archive_write_filter *client_filter;
 464         int ret, r1;
 465
 466         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 467             ARCHIVE_STATE_NEW, "archive_write_open");
 468         archive_clear_error(&a->archive);
 469
 470         a->client_writer = writer;
 471         a->client_opener = opener;
 472         a->client_closer = closer;
 473         a->client_data = client_data;
 474
 475         client_filter = __archive_write_allocate_filter(_a);
 476         client_filter->open = archive_write_client_open;
 477         client_filter->write = archive_write_client_write;
 478         client_filter->close = archive_write_client_close;
 479
 480         ret = __archive_write_open_filter(a->filter_first);
 481         if (ret < ARCHIVE_WARN) {
 482                 r1 = __archive_write_close_filter(a->filter_first);
 483                 return (r1 < ret ? r1 : ret);
 484         }
 485
 486         a->archive.state = ARCHIVE_STATE_HEADER;
 487         if (a->format_init)
 488                 ret = (a->format_init)(a);
 489         return (ret);
 490 }
 491
 492 /*
 493  * Close out the archive.
 494  */
 495 static int
 496 _archive_write_close(struct archive *_a)
 497 {
 498         struct archive_write *a = (struct archive_write *)_a;
 499         int r = ARCHIVE_OK, r1 = ARCHIVE_OK;
 500
 501         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 502             ARCHIVE_STATE_ANY | ARCHIVE_STATE_FATAL,
 503             "archive_write_close");
 504         if (a->archive.state == ARCHIVE_STATE_NEW
 505             || a->archive.state == ARCHIVE_STATE_CLOSED)
 506                 return (ARCHIVE_OK); /* Okay to close() when not open. */
 507
 508         archive_clear_error(&a->archive);
 509
 510         /* Finish the last entry if a finish callback is specified */
 511         if (a->archive.state == ARCHIVE_STATE_DATA
 512             && a->format_finish_entry != NULL)
 513                 r = ((a->format_finish_entry)(a));
 514
 515         /* Finish off the archive. */
 516         /* TODO: have format closers invoke compression close. */
 517         if (a->format_close != NULL) {
 518                 r1 = (a->format_close)(a);
 519                 if (r1 < r)
 520                         r = r1;
 521         }
 522
 523         /* Finish the compression and close the stream. */
 524         r1 = __archive_write_close_filter(a->filter_first);
 525         if (r1 < r)
 526                 r = r1;
 527
 528         if (a->archive.state != ARCHIVE_STATE_FATAL)
 529                 a->archive.state = ARCHIVE_STATE_CLOSED;
 530         return (r);
 531 }
 532
 533 static int
 534 _archive_write_filter_count(struct archive *_a)
 535 {
 536         struct archive_write *a = (struct archive_write *)_a;
 537         struct archive_write_filter *p = a->filter_first;
 538         int count = 0;
 539         while(p) {
 540                 count++;
 541                 p = p->next_filter;
 542         }
 543         return count;
 544 }
 545
 546 void
 547 __archive_write_filters_free(struct archive *_a)
 548 {
 549         struct archive_write *a = (struct archive_write *)_a;
 550         int r = ARCHIVE_OK, r1;
 551
 552         while (a->filter_first != NULL) {
 553                 struct archive_write_filter *next
 554                     = a->filter_first->next_filter;
 555                 if (a->filter_first->free != NULL) {
 556                         r1 = (*a->filter_first->free)(a->filter_first);
 557                         if (r > r1)
 558                                 r = r1;
 559                 }
 560                 free(a->filter_first);
 561                 a->filter_first = next;
 562         }
 563         a->filter_last = NULL;
 564 }
 565
 566 /*
 567  * Destroy the archive structure.
 568  *
 569  * Be careful: user might just call write_new and then write_free.
 570  * Don't assume we actually wrote anything or performed any non-trivial
 571  * initialization.
 572  */
 573 static int
 574 _archive_write_free(struct archive *_a)
 575 {
 576         struct archive_write *a = (struct archive_write *)_a;
 577         int r = ARCHIVE_OK, r1;
 578
 579         if (_a == NULL)
 580                 return (ARCHIVE_OK);
 581         /* It is okay to call free() in state FATAL. */
 582         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 583             ARCHIVE_STATE_ANY | ARCHIVE_STATE_FATAL, "archive_write_free");
 584         if (a->archive.state != ARCHIVE_STATE_FATAL)
 585                 r = archive_write_close(&a->archive);
 586
 587         /* Release format resources. */
 588         if (a->format_free != NULL) {
 589                 r1 = (a->format_free)(a);
 590                 if (r1 < r)
 591                         r = r1;
 592         }
 593
 594         __archive_write_filters_free(_a);
 595
 596         /* Release various dynamic buffers. */
 597         free((void *)(uintptr_t)(const void *)a->nulls);
 598         archive_string_free(&a->archive.error_string);
 599         if (a->passphrase != NULL) {
 600                 /* A passphrase should be cleaned. */
 601                 memset(a->passphrase, 0, strlen(a->passphrase));
 602                 free(a->passphrase);
 603         }
 604         a->archive.magic = 0;
 605         __archive_clean(&a->archive);
 606         free(a);
 607         return (r);
 608 }
 609
 610 /*
 611  * Write the appropriate header.
 612  */
 613 static int
 614 _archive_write_header(struct archive *_a, struct archive_entry *entry)
 615 {
 616         struct archive_write *a = (struct archive_write *)_a;
 617         int ret, r2;
 618
 619         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 620             ARCHIVE_STATE_DATA | ARCHIVE_STATE_HEADER, "archive_write_header");
 621         archive_clear_error(&a->archive);
 622
 623         if (a->format_write_header == NULL) {
 624                 archive_set_error(&(a->archive), -1,
 625                     "Format must be set before you can write to an archive.");
 626                 a->archive.state = ARCHIVE_STATE_FATAL;
 627                 return (ARCHIVE_FATAL);
 628         }
 629
 630         /* In particular, "retry" and "fatal" get returned immediately. */
 631         ret = archive_write_finish_entry(&a->archive);
 632         if (ret == ARCHIVE_FATAL) {
 633                 a->archive.state = ARCHIVE_STATE_FATAL;
 634                 return (ARCHIVE_FATAL);
 635         }
 636         if (ret < ARCHIVE_OK && ret != ARCHIVE_WARN)
 637                 return (ret);
 638
 639         if (a->skip_file_set &&
 640             archive_entry_dev_is_set(entry) &&
 641             archive_entry_ino_is_set(entry) &&
 642             archive_entry_dev(entry) == (dev_t)a->skip_file_dev &&
 643             archive_entry_ino64(entry) == a->skip_file_ino) {
 644                 archive_set_error(&a->archive, 0,
 645                     "Can't add archive to itself");
 646                 return (ARCHIVE_FAILED);
 647         }
 648
 649         /* Format and write header. */
 650         r2 = ((a->format_write_header)(a, entry));
 651         if (r2 == ARCHIVE_FAILED) {
 652                 return (ARCHIVE_FAILED);
 653         }
 654         if (r2 == ARCHIVE_FATAL) {
 655                 a->archive.state = ARCHIVE_STATE_FATAL;
 656                 return (ARCHIVE_FATAL);
 657         }
 658         if (r2 < ret)
 659                 ret = r2;
 660
 661         a->archive.state = ARCHIVE_STATE_DATA;
 662         return (ret);
 663 }
 664
 665 static int
 666 _archive_write_finish_entry(struct archive *_a)
 667 {
 668         struct archive_write *a = (struct archive_write *)_a;
 669         int ret = ARCHIVE_OK;
 670
 671         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 672             ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA,
 673             "archive_write_finish_entry");
 674         if (a->archive.state & ARCHIVE_STATE_DATA
 675             && a->format_finish_entry != NULL)
 676                 ret = (a->format_finish_entry)(a);
 677         a->archive.state = ARCHIVE_STATE_HEADER;
 678         return (ret);
 679 }
 680
 681 /*
 682  * Note that the compressor is responsible for blocking.
 683  */
 684 static ssize_t
 685 _archive_write_data(struct archive *_a, const void *buff, size_t s)
 686 {
 687         struct archive_write *a = (struct archive_write *)_a;
 688         const size_t max_write = INT_MAX;
 689
 690         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
 691             ARCHIVE_STATE_DATA, "archive_write_data");
 692         /* In particular, this catches attempts to pass negative values. */
 693         if (s > max_write)
 694                 s = max_write;
 695         archive_clear_error(&a->archive);
 696         return ((a->format_write_data)(a, buff, s));
 697 }
 698
 699 static struct archive_write_filter *
 700 filter_lookup(struct archive *_a, int n)
 701 {
 702         struct archive_write *a = (struct archive_write *)_a;
 703         struct archive_write_filter *f = a->filter_first;
 704         if (n == -1)
 705                 return a->filter_last;
 706         if (n < 0)
 707                 return NULL;
 708         while (n > 0 && f != NULL) {
 709                 f = f->next_filter;
 710                 --n;
 711         }
 712         return f;
 713 }
 714
 715 static int
 716 _archive_filter_code(struct archive *_a, int n)
 717 {
 718         struct archive_write_filter *f = filter_lookup(_a, n);
 719         return f == NULL ? -1 : f->code;
 720 }
 721
 722 static const char *
 723 _archive_filter_name(struct archive *_a, int n)
 724 {
 725         struct archive_write_filter *f = filter_lookup(_a, n);
 726         return f != NULL ? f->name : NULL;
 727 }
 728
 729 static int64_t
 730 _archive_filter_bytes(struct archive *_a, int n)
 731 {
 732         struct archive_write_filter *f = filter_lookup(_a, n);
 733         return f == NULL ? -1 : f->bytes_written;
 734 }