2 * Copyright (c) 2003-2007 Tim Kientzle
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.
28 #ifndef __LIBARCHIVE_BUILD
29 #error This header is only to be used internally to libarchive.
32 #ifndef ARCHIVE_READ_PRIVATE_H_INCLUDED
33 #define ARCHIVE_READ_PRIVATE_H_INCLUDED
36 #include "archive_string.h"
37 #include "archive_private.h"
40 struct archive_read_filter_bidder;
41 struct archive_read_filter;
44 * How bidding works for filters:
45 * * The bid manager reads the first block from the current source.
46 * * It shows that block to each registered bidder.
47 * * The bid manager creates a new filter structure for the winning
48 * bidder and gives the winning bidder a chance to initialize it.
49 * * The new filter becomes the top filter in the archive_read structure
50 * and we repeat the process.
51 * This ends only when no bidder provides a non-zero bid.
53 struct archive_read_filter_bidder {
54 /* Configuration data for the bidder. */
56 /* Taste the upstream filter to see if we handle this. */
57 int (*bid)(struct archive_read_filter_bidder *,
58 struct archive_read_filter *);
59 /* Initialize a newly-created filter. */
60 int (*init)(struct archive_read_filter *);
61 /* Set an option for the filter bidder. */
62 int (*options)(struct archive_read_filter_bidder *,
63 const char *key, const char *value);
64 /* Release the bidder's configuration data. */
65 int (*free)(struct archive_read_filter_bidder *);
69 * This structure is allocated within the archive_read core
70 * and initialized by archive_read and the init() method of the
71 * corresponding bidder above.
73 struct archive_read_filter {
74 /* Essentially all filters will need these values, so
75 * just declare them here. */
76 struct archive_read_filter_bidder *bidder; /* My bidder. */
77 struct archive_read_filter *upstream; /* Who I read from. */
78 struct archive_read *archive; /* Associated archive. */
79 /* Return next block. */
80 ssize_t (*read)(struct archive_read_filter *, const void **);
81 /* Skip forward this many bytes. */
82 int64_t (*skip)(struct archive_read_filter *self, int64_t request);
83 /* Close (just this filter) and free(self). */
84 int (*close)(struct archive_read_filter *self);
85 /* My private data. */
91 /* Used by reblocking logic. */
94 char *next; /* Current read location. */
95 size_t avail; /* Bytes in my buffer. */
96 const void *client_buff; /* Client buffer information. */
98 const char *client_next;
106 * The client looks a lot like a filter, so we just wrap it here.
108 * TODO: Make archive_read_filter and archive_read_client identical so
109 * that users of the library can easily register their own
110 * transformation filters. This will probably break the API/ABI and
111 * so should be deferred at least until libarchive 3.0.
113 struct archive_read_client {
114 archive_read_callback *reader;
115 archive_skip_callback *skipper;
116 archive_close_callback *closer;
119 struct archive_read {
120 struct archive archive;
122 struct archive_entry *entry;
124 /* Dev/ino of the archive being read/written. */
129 * Used by archive_read_data() to track blocks and copy
130 * data to client buffers, filling gaps with zero bytes.
132 const char *read_data_block;
133 off_t read_data_offset;
134 off_t read_data_output_offset;
135 size_t read_data_remaining;
137 /* Callbacks to open/read/write/close client archive stream. */
138 struct archive_read_client client;
140 /* Registered filter bidders. */
141 struct archive_read_filter_bidder bidders[8];
143 /* Last filter in chain */
144 struct archive_read_filter *filter;
146 /* File offset of beginning of most recently-read header. */
147 off_t header_position;
150 * Format detection is mostly the same as compression
151 * detection, with one significant difference: The bidders
152 * use the read_ahead calls above to examine the stream rather
153 * than having the supervisor hand them a block of data to
157 struct archive_format_descriptor {
160 int (*bid)(struct archive_read *);
161 int (*options)(struct archive_read *, const char *key,
163 int (*read_header)(struct archive_read *, struct archive_entry *);
164 int (*read_data)(struct archive_read *, const void **, size_t *, off_t *);
165 int (*read_data_skip)(struct archive_read *);
166 int (*cleanup)(struct archive_read *);
168 struct archive_format_descriptor *format; /* Active format. */
171 * Various information needed by archive_extract.
173 struct extract *extract;
174 int (*cleanup_archive_extract)(struct archive_read *);
177 int __archive_read_register_format(struct archive_read *a,
180 int (*bid)(struct archive_read *),
181 int (*options)(struct archive_read *, const char *, const char *),
182 int (*read_header)(struct archive_read *, struct archive_entry *),
183 int (*read_data)(struct archive_read *, const void **, size_t *, off_t *),
184 int (*read_data_skip)(struct archive_read *),
185 int (*cleanup)(struct archive_read *));
187 struct archive_read_filter_bidder
188 *__archive_read_get_bidder(struct archive_read *a);
190 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *);
191 const void *__archive_read_filter_ahead(struct archive_read_filter *,
193 ssize_t __archive_read_consume(struct archive_read *, size_t);
194 ssize_t __archive_read_filter_consume(struct archive_read_filter *, size_t);
195 int64_t __archive_read_skip(struct archive_read *, int64_t);
196 int64_t __archive_read_skip_lenient(struct archive_read *, int64_t);
197 int64_t __archive_read_filter_skip(struct archive_read_filter *, int64_t);
198 int __archive_read_program(struct archive_read_filter *, const char *);