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[FreeBSD/stable/10.git] / 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, la_int64_t d, la_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         f->state = ARCHIVE_WRITE_FILTER_STATE_NEW;
216         if (a->filter_first == NULL)
217                 a->filter_first = f;
218         else
219                 a->filter_last->next_filter = f;
220         a->filter_last = f;
221         return f;
222 }
223
224 /*
225  * Write data to a particular filter.
226  */
227 int
228 __archive_write_filter(struct archive_write_filter *f,
229     const void *buff, size_t length)
230 {
231         int r;
232         /* Never write to non-open filters */
233         if (f->state != ARCHIVE_WRITE_FILTER_STATE_OPEN)
234                 return(ARCHIVE_FATAL);
235         if (length == 0)
236                 return(ARCHIVE_OK);
237         if (f->write == NULL)
238                 /* If unset, a fatal error has already occurred, so this filter
239                  * didn't open. We cannot write anything. */
240                 return(ARCHIVE_FATAL);
241         r = (f->write)(f, buff, length);
242         f->bytes_written += length;
243         return (r);
244 }
245
246 /*
247  * Recursive function for opening the filter chain
248  * Last filter is opened first
249  */
250 static int
251 __archive_write_open_filter(struct archive_write_filter *f)
252 {
253         int ret;
254
255         ret = ARCHIVE_OK;
256         if (f->next_filter != NULL)
257                 ret = __archive_write_open_filter(f->next_filter);
258         if (ret != ARCHIVE_OK)
259                 return (ret);
260         if (f->state != ARCHIVE_WRITE_FILTER_STATE_NEW)
261                 return (ARCHIVE_FATAL);
262         if (f->open == NULL) {
263                 f->state = ARCHIVE_WRITE_FILTER_STATE_OPEN;
264                 return (ARCHIVE_OK);
265         }
266         ret = (f->open)(f);
267         if (ret == ARCHIVE_OK)
268                 f->state = ARCHIVE_WRITE_FILTER_STATE_OPEN;
269         else
270                 f->state = ARCHIVE_WRITE_FILTER_STATE_FATAL;
271         return (ret);
272 }
273
274 /*
275  * Open all filters
276  */
277 static int
278 __archive_write_filters_open(struct archive_write *a)
279 {
280         return (__archive_write_open_filter(a->filter_first));
281 }
282
283 /*
284  * Close all filtes
285  */
286 static int
287 __archive_write_filters_close(struct archive_write *a)
288 {
289         struct archive_write_filter *f;
290         int ret, ret1;
291         ret = ARCHIVE_OK;
292         for (f = a->filter_first; f != NULL; f = f->next_filter) {
293                 /* Do not close filters that are not open */
294                 if (f->state == ARCHIVE_WRITE_FILTER_STATE_OPEN) {
295                         if (f->close != NULL) {
296                                 ret1 = (f->close)(f);
297                                 if (ret1 < ret)
298                                         ret = ret1;
299                                 if (ret1 == ARCHIVE_OK) {
300                                         f->state =
301                                             ARCHIVE_WRITE_FILTER_STATE_CLOSED;
302                                 } else {
303                                         f->state =
304                                             ARCHIVE_WRITE_FILTER_STATE_FATAL;
305                                 }
306                         } else
307                                 f->state = ARCHIVE_WRITE_FILTER_STATE_CLOSED;
308                 }
309         }
310         return (ret);
311 }
312
313 int
314 __archive_write_output(struct archive_write *a, const void *buff, size_t length)
315 {
316         return (__archive_write_filter(a->filter_first, buff, length));
317 }
318
319 int
320 __archive_write_nulls(struct archive_write *a, size_t length)
321 {
322         if (length == 0)
323                 return (ARCHIVE_OK);
324
325         while (length > 0) {
326                 size_t to_write = length < a->null_length ? length : a->null_length;
327                 int r = __archive_write_output(a, a->nulls, to_write);
328                 if (r < ARCHIVE_OK)
329                         return (r);
330                 length -= to_write;
331         }
332         return (ARCHIVE_OK);
333 }
334
335 static int
336 archive_write_client_open(struct archive_write_filter *f)
337 {
338         struct archive_write *a = (struct archive_write *)f->archive;
339         struct archive_none *state;
340         void *buffer;
341         size_t buffer_size;
342         int ret;
343
344         f->bytes_per_block = archive_write_get_bytes_per_block(f->archive);
345         f->bytes_in_last_block =
346             archive_write_get_bytes_in_last_block(f->archive);
347         buffer_size = f->bytes_per_block;
348
349         state = (struct archive_none *)calloc(1, sizeof(*state));
350         buffer = (char *)malloc(buffer_size);
351         if (state == NULL || buffer == NULL) {
352                 free(state);
353                 free(buffer);
354                 archive_set_error(f->archive, ENOMEM,
355                     "Can't allocate data for output buffering");
356                 return (ARCHIVE_FATAL);
357         }
358
359         state->buffer_size = buffer_size;
360         state->buffer = buffer;
361         state->next = state->buffer;
362         state->avail = state->buffer_size;
363         f->data = state;
364
365         if (a->client_opener == NULL)
366                 return (ARCHIVE_OK);
367         ret = a->client_opener(f->archive, a->client_data);
368         if (ret != ARCHIVE_OK) {
369                 free(state->buffer);
370                 free(state);
371                 f->data = NULL;
372         }
373         return (ret);
374 }
375
376 static int
377 archive_write_client_write(struct archive_write_filter *f,
378     const void *_buff, size_t length)
379 {
380         struct archive_write *a = (struct archive_write *)f->archive;
381         struct archive_none *state = (struct archive_none *)f->data;
382         const char *buff = (const char *)_buff;
383         ssize_t remaining, to_copy;
384         ssize_t bytes_written;
385
386         remaining = length;
387
388         /*
389          * If there is no buffer for blocking, just pass the data
390          * straight through to the client write callback.  In
391          * particular, this supports "no write delay" operation for
392          * special applications.  Just set the block size to zero.
393          */
394         if (state->buffer_size == 0) {
395                 while (remaining > 0) {
396                         bytes_written = (a->client_writer)(&a->archive,
397                             a->client_data, buff, remaining);
398                         if (bytes_written <= 0)
399                                 return (ARCHIVE_FATAL);
400                         remaining -= bytes_written;
401                         buff += bytes_written;
402                 }
403                 return (ARCHIVE_OK);
404         }
405
406         /* If the copy buffer isn't empty, try to fill it. */
407         if (state->avail < state->buffer_size) {
408                 /* If buffer is not empty... */
409                 /* ... copy data into buffer ... */
410                 to_copy = ((size_t)remaining > state->avail) ?
411                         state->avail : (size_t)remaining;
412                 memcpy(state->next, buff, to_copy);
413                 state->next += to_copy;
414                 state->avail -= to_copy;
415                 buff += to_copy;
416                 remaining -= to_copy;
417                 /* ... if it's full, write it out. */
418                 if (state->avail == 0) {
419                         char *p = state->buffer;
420                         size_t to_write = state->buffer_size;
421                         while (to_write > 0) {
422                                 bytes_written = (a->client_writer)(&a->archive,
423                                     a->client_data, p, to_write);
424                                 if (bytes_written <= 0)
425                                         return (ARCHIVE_FATAL);
426                                 if ((size_t)bytes_written > to_write) {
427                                         archive_set_error(&(a->archive),
428                                             -1, "write overrun");
429                                         return (ARCHIVE_FATAL);
430                                 }
431                                 p += bytes_written;
432                                 to_write -= bytes_written;
433                         }
434                         state->next = state->buffer;
435                         state->avail = state->buffer_size;
436                 }
437         }
438
439         while ((size_t)remaining >= state->buffer_size) {
440                 /* Write out full blocks directly to client. */
441                 bytes_written = (a->client_writer)(&a->archive,
442                     a->client_data, buff, state->buffer_size);
443                 if (bytes_written <= 0)
444                         return (ARCHIVE_FATAL);
445                 buff += bytes_written;
446                 remaining -= bytes_written;
447         }
448
449         if (remaining > 0) {
450                 /* Copy last bit into copy buffer. */
451                 memcpy(state->next, buff, remaining);
452                 state->next += remaining;
453                 state->avail -= remaining;
454         }
455         return (ARCHIVE_OK);
456 }
457
458 static int
459 archive_write_client_free(struct archive_write_filter *f)
460 {
461         struct archive_write *a = (struct archive_write *)f->archive;
462
463         if (a->client_freer)
464                 (*a->client_freer)(&a->archive, a->client_data);
465         a->client_data = NULL;
466
467         /* Clear passphrase. */
468         if (a->passphrase != NULL) {
469                 memset(a->passphrase, 0, strlen(a->passphrase));
470                 free(a->passphrase);
471                 a->passphrase = NULL;
472         }
473
474         return (ARCHIVE_OK);
475 }
476
477 static int
478 archive_write_client_close(struct archive_write_filter *f)
479 {
480         struct archive_write *a = (struct archive_write *)f->archive;
481         struct archive_none *state = (struct archive_none *)f->data;
482         ssize_t block_length;
483         ssize_t target_block_length;
484         ssize_t bytes_written;
485         int ret = ARCHIVE_OK;
486
487         /* If there's pending data, pad and write the last block */
488         if (state->next != state->buffer) {
489                 block_length = state->buffer_size - state->avail;
490
491                 /* Tricky calculation to determine size of last block */
492                 if (a->bytes_in_last_block <= 0)
493                         /* Default or Zero: pad to full block */
494                         target_block_length = a->bytes_per_block;
495                 else
496                         /* Round to next multiple of bytes_in_last_block. */
497                         target_block_length = a->bytes_in_last_block *
498                             ( (block_length + a->bytes_in_last_block - 1) /
499                                 a->bytes_in_last_block);
500                 if (target_block_length > a->bytes_per_block)
501                         target_block_length = a->bytes_per_block;
502                 if (block_length < target_block_length) {
503                         memset(state->next, 0,
504                             target_block_length - block_length);
505                         block_length = target_block_length;
506                 }
507                 bytes_written = (a->client_writer)(&a->archive,
508                     a->client_data, state->buffer, block_length);
509                 ret = bytes_written <= 0 ? ARCHIVE_FATAL : ARCHIVE_OK;
510         }
511         if (a->client_closer)
512                 (*a->client_closer)(&a->archive, a->client_data);
513         free(state->buffer);
514         free(state);
515
516         /* Clear the close handler myself not to be called again. */
517         f->state = ARCHIVE_WRITE_FILTER_STATE_CLOSED;
518         return (ret);
519 }
520
521 /*
522  * Open the archive using the current settings.
523  */
524 int
525 archive_write_open2(struct archive *_a, void *client_data,
526     archive_open_callback *opener, archive_write_callback *writer,
527     archive_close_callback *closer, archive_free_callback *freer)
528 {
529         struct archive_write *a = (struct archive_write *)_a;
530         struct archive_write_filter *client_filter;
531         int ret, r1;
532
533         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
534             ARCHIVE_STATE_NEW, "archive_write_open");
535         archive_clear_error(&a->archive);
536
537         a->client_writer = writer;
538         a->client_opener = opener;
539         a->client_closer = closer;
540         a->client_freer = freer;
541         a->client_data = client_data;
542
543         client_filter = __archive_write_allocate_filter(_a);
544         client_filter->open = archive_write_client_open;
545         client_filter->write = archive_write_client_write;
546         client_filter->close = archive_write_client_close;
547         client_filter->free = archive_write_client_free;
548
549         ret = __archive_write_filters_open(a);
550         if (ret < ARCHIVE_WARN) {
551                 r1 = __archive_write_filters_close(a);
552                 __archive_write_filters_free(_a);
553                 return (r1 < ret ? r1 : ret);
554         }
555
556         a->archive.state = ARCHIVE_STATE_HEADER;
557         if (a->format_init)
558                 ret = (a->format_init)(a);
559         return (ret);
560 }
561
562 int
563 archive_write_open(struct archive *_a, void *client_data,
564     archive_open_callback *opener, archive_write_callback *writer,
565     archive_close_callback *closer)
566 {
567         return archive_write_open2(_a, client_data, opener, writer,
568             closer, NULL);
569 }
570
571 /*
572  * Close out the archive.
573  */
574 static int
575 _archive_write_close(struct archive *_a)
576 {
577         struct archive_write *a = (struct archive_write *)_a;
578         int r = ARCHIVE_OK, r1 = ARCHIVE_OK;
579
580         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
581             ARCHIVE_STATE_ANY | ARCHIVE_STATE_FATAL,
582             "archive_write_close");
583         if (a->archive.state == ARCHIVE_STATE_NEW
584             || a->archive.state == ARCHIVE_STATE_CLOSED)
585                 return (ARCHIVE_OK); /* Okay to close() when not open. */
586
587         archive_clear_error(&a->archive);
588
589         /* Finish the last entry if a finish callback is specified */
590         if (a->archive.state == ARCHIVE_STATE_DATA
591             && a->format_finish_entry != NULL)
592                 r = ((a->format_finish_entry)(a));
593
594         /* Finish off the archive. */
595         /* TODO: have format closers invoke compression close. */
596         if (a->format_close != NULL) {
597                 r1 = (a->format_close)(a);
598                 if (r1 < r)
599                         r = r1;
600         }
601
602         /* Finish the compression and close the stream. */
603         r1 = __archive_write_filters_close(a);
604         if (r1 < r)
605                 r = r1;
606
607         if (a->archive.state != ARCHIVE_STATE_FATAL)
608                 a->archive.state = ARCHIVE_STATE_CLOSED;
609         return (r);
610 }
611
612 static int
613 _archive_write_filter_count(struct archive *_a)
614 {
615         struct archive_write *a = (struct archive_write *)_a;
616         struct archive_write_filter *p = a->filter_first;
617         int count = 0;
618         while(p) {
619                 count++;
620                 p = p->next_filter;
621         }
622         return count;
623 }
624
625 void
626 __archive_write_filters_free(struct archive *_a)
627 {
628         struct archive_write *a = (struct archive_write *)_a;
629         int r = ARCHIVE_OK, r1;
630
631         while (a->filter_first != NULL) {
632                 struct archive_write_filter *next
633                     = a->filter_first->next_filter;
634                 if (a->filter_first->free != NULL) {
635                         r1 = (*a->filter_first->free)(a->filter_first);
636                         if (r > r1)
637                                 r = r1;
638                 }
639                 free(a->filter_first);
640                 a->filter_first = next;
641         }
642         a->filter_last = NULL;
643 }
644
645 /*
646  * Destroy the archive structure.
647  *
648  * Be careful: user might just call write_new and then write_free.
649  * Don't assume we actually wrote anything or performed any non-trivial
650  * initialization.
651  */
652 static int
653 _archive_write_free(struct archive *_a)
654 {
655         struct archive_write *a = (struct archive_write *)_a;
656         int r = ARCHIVE_OK, r1;
657
658         if (_a == NULL)
659                 return (ARCHIVE_OK);
660         /* It is okay to call free() in state FATAL. */
661         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
662             ARCHIVE_STATE_ANY | ARCHIVE_STATE_FATAL, "archive_write_free");
663         if (a->archive.state != ARCHIVE_STATE_FATAL)
664                 r = archive_write_close(&a->archive);
665
666         /* Release format resources. */
667         if (a->format_free != NULL) {
668                 r1 = (a->format_free)(a);
669                 if (r1 < r)
670                         r = r1;
671         }
672
673         __archive_write_filters_free(_a);
674
675         /* Release various dynamic buffers. */
676         free((void *)(uintptr_t)(const void *)a->nulls);
677         archive_string_free(&a->archive.error_string);
678         if (a->passphrase != NULL) {
679                 /* A passphrase should be cleaned. */
680                 memset(a->passphrase, 0, strlen(a->passphrase));
681                 free(a->passphrase);
682         }
683         a->archive.magic = 0;
684         __archive_clean(&a->archive);
685         free(a);
686         return (r);
687 }
688
689 /*
690  * Write the appropriate header.
691  */
692 static int
693 _archive_write_header(struct archive *_a, struct archive_entry *entry)
694 {
695         struct archive_write *a = (struct archive_write *)_a;
696         int ret, r2;
697
698         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
699             ARCHIVE_STATE_DATA | ARCHIVE_STATE_HEADER, "archive_write_header");
700         archive_clear_error(&a->archive);
701
702         if (a->format_write_header == NULL) {
703                 archive_set_error(&(a->archive), -1,
704                     "Format must be set before you can write to an archive.");
705                 a->archive.state = ARCHIVE_STATE_FATAL;
706                 return (ARCHIVE_FATAL);
707         }
708
709         /* In particular, "retry" and "fatal" get returned immediately. */
710         ret = archive_write_finish_entry(&a->archive);
711         if (ret == ARCHIVE_FATAL) {
712                 a->archive.state = ARCHIVE_STATE_FATAL;
713                 return (ARCHIVE_FATAL);
714         }
715         if (ret < ARCHIVE_OK && ret != ARCHIVE_WARN)
716                 return (ret);
717
718         if (a->skip_file_set &&
719             archive_entry_dev_is_set(entry) &&
720             archive_entry_ino_is_set(entry) &&
721             archive_entry_dev(entry) == (dev_t)a->skip_file_dev &&
722             archive_entry_ino64(entry) == a->skip_file_ino) {
723                 archive_set_error(&a->archive, 0,
724                     "Can't add archive to itself");
725                 return (ARCHIVE_FAILED);
726         }
727
728         /* Format and write header. */
729         r2 = ((a->format_write_header)(a, entry));
730         if (r2 == ARCHIVE_FAILED) {
731                 return (ARCHIVE_FAILED);
732         }
733         if (r2 == ARCHIVE_FATAL) {
734                 a->archive.state = ARCHIVE_STATE_FATAL;
735                 return (ARCHIVE_FATAL);
736         }
737         if (r2 < ret)
738                 ret = r2;
739
740         a->archive.state = ARCHIVE_STATE_DATA;
741         return (ret);
742 }
743
744 static int
745 _archive_write_finish_entry(struct archive *_a)
746 {
747         struct archive_write *a = (struct archive_write *)_a;
748         int ret = ARCHIVE_OK;
749
750         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
751             ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA,
752             "archive_write_finish_entry");
753         if (a->archive.state & ARCHIVE_STATE_DATA
754             && a->format_finish_entry != NULL)
755                 ret = (a->format_finish_entry)(a);
756         a->archive.state = ARCHIVE_STATE_HEADER;
757         return (ret);
758 }
759
760 /*
761  * Note that the compressor is responsible for blocking.
762  */
763 static ssize_t
764 _archive_write_data(struct archive *_a, const void *buff, size_t s)
765 {
766         struct archive_write *a = (struct archive_write *)_a;
767         const size_t max_write = INT_MAX;
768
769         archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
770             ARCHIVE_STATE_DATA, "archive_write_data");
771         /* In particular, this catches attempts to pass negative values. */
772         if (s > max_write)
773                 s = max_write;
774         archive_clear_error(&a->archive);
775         return ((a->format_write_data)(a, buff, s));
776 }
777
778 static struct archive_write_filter *
779 filter_lookup(struct archive *_a, int n)
780 {
781         struct archive_write *a = (struct archive_write *)_a;
782         struct archive_write_filter *f = a->filter_first;
783         if (n == -1)
784                 return a->filter_last;
785         if (n < 0)
786                 return NULL;
787         while (n > 0 && f != NULL) {
788                 f = f->next_filter;
789                 --n;
790         }
791         return f;
792 }
793
794 static int
795 _archive_filter_code(struct archive *_a, int n)
796 {
797         struct archive_write_filter *f = filter_lookup(_a, n);
798         return f == NULL ? -1 : f->code;
799 }
800
801 static const char *
802 _archive_filter_name(struct archive *_a, int n)
803 {
804         struct archive_write_filter *f = filter_lookup(_a, n);
805         return f != NULL ? f->name : NULL;
806 }
807
808 static int64_t
809 _archive_filter_bytes(struct archive *_a, int n)
810 {
811         struct archive_write_filter *f = filter_lookup(_a, n);
812         return f == NULL ? -1 : f->bytes_written;
813 }