2 * Copyright (c) 2012 Michihiro NAKAJIMA
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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.
26 #include "archive_platform.h"
28 __FBSDID("$FreeBSD$");
45 #include "archive_private.h"
46 #include "archive_read_private.h"
48 static const unsigned char grzip_magic[] = {
49 0x47, 0x52, 0x5a, 0x69, 0x70, 0x49, 0x49, 0x00,
50 0x02, 0x04, 0x3a, 0x29 };
52 static int grzip_bidder_bid(struct archive_read_filter_bidder *,
53 struct archive_read_filter *);
54 static int grzip_bidder_init(struct archive_read_filter *);
57 static const struct archive_read_filter_bidder_vtable
58 grzip_bidder_vtable = {
59 .bid = grzip_bidder_bid,
60 .init = grzip_bidder_init,
64 archive_read_support_filter_grzip(struct archive *_a)
66 struct archive_read *a = (struct archive_read *)_a;
68 if (__archive_read_register_bidder(a, NULL, NULL,
69 &grzip_bidder_vtable) != ARCHIVE_OK)
70 return (ARCHIVE_FATAL);
72 /* This filter always uses an external program. */
73 archive_set_error(_a, ARCHIVE_ERRNO_MISC,
74 "Using external grzip program for grzip decompression");
75 return (ARCHIVE_WARN);
79 * Bidder just verifies the header and returns the number of verified bits.
82 grzip_bidder_bid(struct archive_read_filter_bidder *self,
83 struct archive_read_filter *filter)
85 const unsigned char *p;
88 (void)self; /* UNUSED */
90 p = __archive_read_filter_ahead(filter, sizeof(grzip_magic), &avail);
91 if (p == NULL || avail == 0)
94 if (memcmp(p, grzip_magic, sizeof(grzip_magic)))
97 return (sizeof(grzip_magic) * 8);
101 grzip_bidder_init(struct archive_read_filter *self)
105 r = __archive_read_program(self, "grzip -d");
106 /* Note: We set the format here even if __archive_read_program()
107 * above fails. We do, after all, know what the format is
108 * even if we weren't able to read it. */
109 self->code = ARCHIVE_FILTER_GRZIP;
110 self->name = "grzip";