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 * $FreeBSD: head/lib/libarchive/archive_read_private.h 201088 2009-12-28 02:18:55Z kientzle $ 26 */ 27 28 #ifndef __LIBARCHIVE_BUILD 29 #error This header is only to be used internally to libarchive. 30 #endif 31 32 #ifndef ARCHIVE_READ_PRIVATE_H_INCLUDED 33 #define ARCHIVE_READ_PRIVATE_H_INCLUDED 34 35 #include "archive.h" 36 #include "archive_string.h" 37 #include "archive_private.h" 38 39 struct archive_read; 40 struct archive_read_filter_bidder; 41 struct archive_read_filter; 42 43 /* 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. 52 */ 53 struct archive_read_filter_bidder { 54 /* Configuration data for the bidder. */ 55 void *data; 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 *); 66 }; 67 68 /* 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. 72 */ 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. */ 86 void *data; 87 88 const char *name; 89 int code; 90 91 /* Used by reblocking logic. */ 92 char *buffer; 93 size_t buffer_size; 94 char *next; /* Current read location. */ 95 size_t avail; /* Bytes in my buffer. */ 96 const void *client_buff; /* Client buffer information. */ 97 size_t client_total; 98 const char *client_next; 99 size_t client_avail; 100 int64_t position; 101 char end_of_file; 102 char fatal; 103 }; 104 105 /* 106 * The client looks a lot like a filter, so we just wrap it here. 107 * 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. 112 */ 113 struct archive_read_client { 114 archive_read_callback *reader; 115 archive_skip_callback *skipper; 116 archive_close_callback *closer; 117 }; 118 119 struct archive_read { 120 struct archive archive; 121 122 struct archive_entry *entry; 123 124 /* Dev/ino of the archive being read/written. */ 125 dev_t skip_file_dev; 126 ino_t skip_file_ino; 127 128 /* 129 * Used by archive_read_data() to track blocks and copy 130 * data to client buffers, filling gaps with zero bytes. 131 */ 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; 136 137 /* Callbacks to open/read/write/close client archive stream. */ 138 struct archive_read_client client; 139 140 /* Registered filter bidders. */ 141 struct archive_read_filter_bidder bidders[8]; 142 143 /* Last filter in chain */ 144 struct archive_read_filter *filter; 145 146 /* File offset of beginning of most recently-read header. */ 147 off_t header_position; 148 149 /* 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 154 * examine. 155 */ 156 157 struct archive_format_descriptor { 158 void *data; 159 const char *name; 160 int (*bid)(struct archive_read *); 161 int (*options)(struct archive_read *, const char *key, 162 const char *value); 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 *); 167 } formats[9]; 168 struct archive_format_descriptor *format; /* Active format. */ 169 170 /* 171 * Various information needed by archive_extract. 172 */ 173 struct extract *extract; 174 int (*cleanup_archive_extract)(struct archive_read *); 175 }; 176 177 int __archive_read_register_format(struct archive_read *a, 178 void *format_data, 179 const char *name, 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 *)); 186 187 struct archive_read_filter_bidder 188 *__archive_read_get_bidder(struct archive_read *a); 189 190 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *); 191 const void *__archive_read_filter_ahead(struct archive_read_filter *, 192 size_t, ssize_t *); 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 *); 199 #endif 200