archive_read_support_format_empty.c 3.0 KB

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  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. #include "archive_platform.h"
  26. __FBSDID("$FreeBSD: src/lib/libarchive/archive_read_support_format_empty.c,v 1.4 2008/12/06 06:45:15 kientzle Exp $");
  27. #include "archive.h"
  28. #include "archive_entry.h"
  29. #include "archive_private.h"
  30. #include "archive_read_private.h"
  31. static int archive_read_format_empty_bid(struct archive_read *);
  32. static int archive_read_format_empty_read_data(struct archive_read *,
  33. const void **, size_t *, off_t *);
  34. static int archive_read_format_empty_read_header(struct archive_read *,
  35. struct archive_entry *);
  36. int
  37. archive_read_support_format_empty(struct archive *_a)
  38. {
  39. struct archive_read *a = (struct archive_read *)_a;
  40. int r;
  41. r = __archive_read_register_format(a,
  42. NULL,
  43. NULL,
  44. archive_read_format_empty_bid,
  45. NULL,
  46. archive_read_format_empty_read_header,
  47. archive_read_format_empty_read_data,
  48. NULL,
  49. NULL);
  50. return (r);
  51. }
  52. static int
  53. archive_read_format_empty_bid(struct archive_read *a)
  54. {
  55. ssize_t avail;
  56. (void)__archive_read_ahead(a, 1, &avail);
  57. if (avail != 0)
  58. return (-1);
  59. return (1);
  60. }
  61. static int
  62. archive_read_format_empty_read_header(struct archive_read *a,
  63. struct archive_entry *entry)
  64. {
  65. (void)a; /* UNUSED */
  66. (void)entry; /* UNUSED */
  67. a->archive.archive_format = ARCHIVE_FORMAT_EMPTY;
  68. a->archive.archive_format_name = "Empty file";
  69. return (ARCHIVE_EOF);
  70. }
  71. static int
  72. archive_read_format_empty_read_data(struct archive_read *a,
  73. const void **buff, size_t *size, off_t *offset)
  74. {
  75. (void)a; /* UNUSED */
  76. (void)buff; /* UNUSED */
  77. (void)size; /* UNUSED */
  78. (void)offset; /* UNUSED */
  79. return (ARCHIVE_EOF);
  80. }