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 *); 35 static int archive_read_format_empty_read_data(struct archive_read *, 36 const void **, size_t *, off_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 r = __archive_read_register_format(a, 46 NULL, 47 NULL, 48 archive_read_format_empty_bid, 49 NULL, 50 archive_read_format_empty_read_header, 51 archive_read_format_empty_read_data, 52 NULL, 53 NULL); 54 55 return (r); 56 } 57 58 59 static int 60 archive_read_format_empty_bid(struct archive_read *a) 61 { 62 ssize_t avail; 63 64 (void)__archive_read_ahead(a, 1, &avail); 65 if (avail != 0) 66 return (-1); 67 return (1); 68 } 69 70 static int 71 archive_read_format_empty_read_header(struct archive_read *a, 72 struct archive_entry *entry) 73 { 74 (void)a; /* UNUSED */ 75 (void)entry; /* UNUSED */ 76 77 a->archive.archive_format = ARCHIVE_FORMAT_EMPTY; 78 a->archive.archive_format_name = "Empty file"; 79 80 return (ARCHIVE_EOF); 81 } 82 83 static int 84 archive_read_format_empty_read_data(struct archive_read *a, 85 const void **buff, size_t *size, off_t *offset) 86 { 87 (void)a; /* UNUSED */ 88 (void)buff; /* UNUSED */ 89 (void)size; /* UNUSED */ 90 (void)offset; /* UNUSED */ 91 92 return (ARCHIVE_EOF); 93 } 94