contrib/libarchive/libarchive/archive_read_support_format_empty.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 __FBSDID("$FreeBSD: head/lib/libarchive/archive_read_support_format_empty.c 191524 2009-04-26 18:24:14Z kientzle $");
  28
  29 #include "archive.h"
  30 #include "archive_entry.h"
  31 #include "archive_private.h"
  32 #include "archive_read_private.h"
  33
  34 static int      archive_read_format_empty_bid(struct archive_read *, int);
  35 static int      archive_read_format_empty_read_data(struct archive_read *,
  36                     const void **, size_t *, int64_t *);
  37 static int      archive_read_format_empty_read_header(struct archive_read *,
  38                     struct archive_entry *);
  39 int
  40 archive_read_support_format_empty(struct archive *_a)
  41 {
  42         struct archive_read *a = (struct archive_read *)_a;
  43         int r;
  44
  45         archive_check_magic(_a, ARCHIVE_READ_MAGIC,
  46             ARCHIVE_STATE_NEW, "archive_read_support_format_empty");
  47
  48         r = __archive_read_register_format(a,
  49             NULL,
  50             NULL,
  51             archive_read_format_empty_bid,
  52             NULL,
  53             archive_read_format_empty_read_header,
  54             archive_read_format_empty_read_data,
  55             NULL,
  56             NULL,
  57             NULL,
  58             NULL,
  59             NULL);
  60
  61         return (r);
  62 }
  63
  64
  65 static int
  66 archive_read_format_empty_bid(struct archive_read *a, int best_bid)
  67 {
  68         if (best_bid < 1 && __archive_read_ahead(a, 1, NULL) == NULL)
  69                 return (1);
  70         return (-1);
  71 }
  72
  73 static int
  74 archive_read_format_empty_read_header(struct archive_read *a,
  75     struct archive_entry *entry)
  76 {
  77         (void)a; /* UNUSED */
  78         (void)entry; /* UNUSED */
  79
  80         a->archive.archive_format = ARCHIVE_FORMAT_EMPTY;
  81         a->archive.archive_format_name = "Empty file";
  82
  83         return (ARCHIVE_EOF);
  84 }
  85
  86 static int
  87 archive_read_format_empty_read_data(struct archive_read *a,
  88     const void **buff, size_t *size, int64_t *offset)
  89 {
  90         (void)a; /* UNUSED */
  91         (void)buff; /* UNUSED */
  92         (void)size; /* UNUSED */
  93         (void)offset; /* UNUSED */
  94
  95         return (ARCHIVE_EOF);
  96 }