1 /*-
2 * Copyright (c) 2003-2009 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: head/lib/libarchive/archive_read_support_format_raw.c 201107 2009-12-28 03:25:33Z kientzle $");
27
28 #ifdef HAVE_ERRNO_H
29 #include <errno.h>
30 #endif
31 #include <stdio.h>
32 #ifdef HAVE_STDLIB_H
33 #include <stdlib.h>
34 #endif
35
36 #include "archive.h"
37 #include "archive_entry.h"
38 #include "archive_private.h"
39 #include "archive_read_private.h"
40
41 struct raw_info {
42 int64_t offset; /* Current position in the file. */
43 int64_t unconsumed;
44 int end_of_file;
45 };
46
47 static int archive_read_format_raw_bid(struct archive_read *, int);
48 static int archive_read_format_raw_cleanup(struct archive_read *);
49 static int archive_read_format_raw_read_data(struct archive_read *,
50 const void **, size_t *, int64_t *);
51 static int archive_read_format_raw_read_data_skip(struct archive_read *);
52 static int archive_read_format_raw_read_header(struct archive_read *,
53 struct archive_entry *);
54
55 int
archive_read_support_format_raw(struct archive * _a)56 archive_read_support_format_raw(struct archive *_a)
57 {
58 struct raw_info *info;
59 struct archive_read *a = (struct archive_read *)_a;
60 int r;
61
62 archive_check_magic(_a, ARCHIVE_READ_MAGIC,
63 ARCHIVE_STATE_NEW, "archive_read_support_format_raw");
64
65 info = (struct raw_info *)calloc(1, sizeof(*info));
66 if (info == NULL) {
67 archive_set_error(&a->archive, ENOMEM,
68 "Can't allocate raw_info data");
69 return (ARCHIVE_FATAL);
70 }
71
72 r = __archive_read_register_format(a,
73 info,
74 "raw",
75 archive_read_format_raw_bid,
76 NULL,
77 archive_read_format_raw_read_header,
78 archive_read_format_raw_read_data,
79 archive_read_format_raw_read_data_skip,
80 NULL,
81 archive_read_format_raw_cleanup,
82 NULL,
83 NULL);
84 if (r != ARCHIVE_OK)
85 free(info);
86 return (r);
87 }
88
89 /*
90 * Bid 1 if this is a non-empty file. Anyone who can really support
91 * this should outbid us, so it should generally be safe to use "raw"
92 * in conjunction with other formats. But, this could really confuse
93 * folks if there are bid errors or minor file damage, so we don't
94 * include "raw" as part of support_format_all().
95 */
96 static int
archive_read_format_raw_bid(struct archive_read * a,int best_bid)97 archive_read_format_raw_bid(struct archive_read *a, int best_bid)
98 {
99 if (best_bid < 1 && __archive_read_ahead(a, 1, NULL) != NULL)
100 return (1);
101 return (-1);
102 }
103
104 /*
105 * Mock up a fake header.
106 */
107 static int
archive_read_format_raw_read_header(struct archive_read * a,struct archive_entry * entry)108 archive_read_format_raw_read_header(struct archive_read *a,
109 struct archive_entry *entry)
110 {
111 struct raw_info *info;
112
113 info = (struct raw_info *)(a->format->data);
114 if (info->end_of_file)
115 return (ARCHIVE_EOF);
116
117 a->archive.archive_format = ARCHIVE_FORMAT_RAW;
118 a->archive.archive_format_name = "raw";
119 archive_entry_set_pathname(entry, "data");
120 archive_entry_set_filetype(entry, AE_IFREG);
121 archive_entry_set_perm(entry, 0644);
122 /* I'm deliberately leaving most fields unset here. */
123
124 /* Let the filter fill out any fields it might have. */
125 return __archive_read_header(a, entry);
126 }
127
128 static int
archive_read_format_raw_read_data(struct archive_read * a,const void ** buff,size_t * size,int64_t * offset)129 archive_read_format_raw_read_data(struct archive_read *a,
130 const void **buff, size_t *size, int64_t *offset)
131 {
132 struct raw_info *info;
133 ssize_t avail;
134
135 info = (struct raw_info *)(a->format->data);
136
137 /* Consume the bytes we read last time. */
138 if (info->unconsumed) {
139 __archive_read_consume(a, info->unconsumed);
140 info->unconsumed = 0;
141 }
142
143 if (info->end_of_file)
144 return (ARCHIVE_EOF);
145
146 /* Get whatever bytes are immediately available. */
147 *buff = __archive_read_ahead(a, 1, &avail);
148 if (avail > 0) {
149 /* Return the bytes we just read */
150 *size = avail;
151 *offset = info->offset;
152 info->offset += *size;
153 info->unconsumed = avail;
154 return (ARCHIVE_OK);
155 } else if (0 == avail) {
156 /* Record and return end-of-file. */
157 info->end_of_file = 1;
158 *size = 0;
159 *offset = info->offset;
160 return (ARCHIVE_EOF);
161 } else {
162 /* Record and return an error. */
163 *size = 0;
164 *offset = info->offset;
165 return ((int)avail);
166 }
167 }
168
169 static int
archive_read_format_raw_read_data_skip(struct archive_read * a)170 archive_read_format_raw_read_data_skip(struct archive_read *a)
171 {
172 struct raw_info *info = (struct raw_info *)(a->format->data);
173
174 /* Consume the bytes we read last time. */
175 if (info->unconsumed) {
176 __archive_read_consume(a, info->unconsumed);
177 info->unconsumed = 0;
178 }
179 info->end_of_file = 1;
180 return (ARCHIVE_OK);
181 }
182
183 static int
archive_read_format_raw_cleanup(struct archive_read * a)184 archive_read_format_raw_cleanup(struct archive_read *a)
185 {
186 struct raw_info *info;
187
188 info = (struct raw_info *)(a->format->data);
189 free(info);
190 a->format->data = NULL;
191 return (ARCHIVE_OK);
192 }
193