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 #ifndef __LIBARCHIVE_TEST 30 #error This header is only to be used internally to libarchive. 31 #endif 32 #endif 33 34 #ifndef ARCHIVE_READ_PRIVATE_H_INCLUDED 35 #define ARCHIVE_READ_PRIVATE_H_INCLUDED 36 37 #include "archive.h" 38 #include "archive_string.h" 39 #include "archive_private.h" 40 41 struct archive_read; 42 struct archive_read_filter_bidder; 43 struct archive_read_filter; 44 45 /* 46 * How bidding works for filters: 47 * * The bid manager initializes the client-provided reader as the 48 * first filter. 49 * * It invokes the bidder for each registered filter with the 50 * current head filter. 51 * * The bidders can use archive_read_filter_ahead() to peek ahead 52 * at the incoming data to compose their bids. 53 * * The bid manager creates a new filter structure for the winning 54 * bidder and gives the winning bidder a chance to initialize it. 55 * * The new filter becomes the new top filter and we repeat the 56 * process. 57 * This ends only when no bidder provides a non-zero bid. Then 58 * we perform a similar dance with the registered format handlers. 59 */ 60 struct archive_read_filter_bidder { 61 /* Configuration data for the bidder. */ 62 void *data; 63 /* Name of the filter */ 64 const char *name; 65 /* Taste the upstream filter to see if we handle this. */ 66 int (*bid)(struct archive_read_filter_bidder *, 67 struct archive_read_filter *); 68 /* Initialize a newly-created filter. */ 69 int (*init)(struct archive_read_filter *); 70 /* Set an option for the filter bidder. */ 71 int (*options)(struct archive_read_filter_bidder *, 72 const char *key, const char *value); 73 /* Release the bidder's configuration data. */ 74 int (*free)(struct archive_read_filter_bidder *); 75 }; 76 77 /* 78 * This structure is allocated within the archive_read core 79 * and initialized by archive_read and the init() method of the 80 * corresponding bidder above. 81 */ 82 struct archive_read_filter { 83 int64_t position; 84 /* Essentially all filters will need these values, so 85 * just declare them here. */ 86 struct archive_read_filter_bidder *bidder; /* My bidder. */ 87 struct archive_read_filter *upstream; /* Who I read from. */ 88 struct archive_read *archive; /* Associated archive. */ 89 /* Open a block for reading */ 90 int (*open)(struct archive_read_filter *self); 91 /* Return next block. */ 92 ssize_t (*read)(struct archive_read_filter *, const void **); 93 /* Skip forward this many bytes. */ 94 int64_t (*skip)(struct archive_read_filter *self, int64_t request); 95 /* Seek to an absolute location. */ 96 int64_t (*seek)(struct archive_read_filter *self, int64_t offset, int whence); 97 /* Close (just this filter) and free(self). */ 98 int (*close)(struct archive_read_filter *self); 99 /* Function that handles switching from reading one block to the next/prev */ 100 int (*sswitch)(struct archive_read_filter *self, unsigned int iindex); 101 /* My private data. */ 102 void *data; 103 104 const char *name; 105 int code; 106 107 /* Used by reblocking logic. */ 108 char *buffer; 109 size_t buffer_size; 110 char *next; /* Current read location. */ 111 size_t avail; /* Bytes in my buffer. */ 112 const void *client_buff; /* Client buffer information. */ 113 size_t client_total; 114 const char *client_next; 115 size_t client_avail; 116 char end_of_file; 117 char closed; 118 char fatal; 119 }; 120 121 /* 122 * The client looks a lot like a filter, so we just wrap it here. 123 * 124 * TODO: Make archive_read_filter and archive_read_client identical so 125 * that users of the library can easily register their own 126 * transformation filters. This will probably break the API/ABI and 127 * so should be deferred at least until libarchive 3.0. 128 */ 129 struct archive_read_data_node { 130 int64_t begin_position; 131 int64_t total_size; 132 void *data; 133 }; 134 struct archive_read_client { 135 archive_open_callback *opener; 136 archive_read_callback *reader; 137 archive_skip_callback *skipper; 138 archive_seek_callback *seeker; 139 archive_close_callback *closer; 140 archive_switch_callback *switcher; 141 unsigned int nodes; 142 unsigned int cursor; 143 int64_t position; 144 struct archive_read_data_node *dataset; 145 }; 146 struct archive_read_passphrase { 147 char *passphrase; 148 struct archive_read_passphrase *next; 149 }; 150 151 struct archive_read_extract { 152 struct archive *ad; /* archive_write_disk object */ 153 154 /* Progress function invoked during extract. */ 155 void (*extract_progress)(void *); 156 void *extract_progress_user_data; 157 }; 158 159 struct archive_read { 160 struct archive archive; 161 162 struct archive_entry *entry; 163 164 /* Dev/ino of the archive being read/written. */ 165 int skip_file_set; 166 int64_t skip_file_dev; 167 int64_t skip_file_ino; 168 169 /* Callbacks to open/read/write/close client archive streams. */ 170 struct archive_read_client client; 171 172 /* Registered filter bidders. */ 173 struct archive_read_filter_bidder bidders[16]; 174 175 /* Last filter in chain */ 176 struct archive_read_filter *filter; 177 178 /* Whether to bypass filter bidding process */ 179 int bypass_filter_bidding; 180 181 /* File offset of beginning of most recently-read header. */ 182 int64_t header_position; 183 184 /* Nodes and offsets of compressed data block */ 185 unsigned int data_start_node; 186 unsigned int data_end_node; 187 188 /* 189 * Format detection is mostly the same as compression 190 * detection, with one significant difference: The bidders 191 * use the read_ahead calls above to examine the stream rather 192 * than having the supervisor hand them a block of data to 193 * examine. 194 */ 195 196 struct archive_format_descriptor { 197 void *data; 198 const char *name; 199 int (*bid)(struct archive_read *, int best_bid); 200 int (*options)(struct archive_read *, const char *key, 201 const char *value); 202 int (*read_header)(struct archive_read *, struct archive_entry *); 203 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *); 204 int (*read_data_skip)(struct archive_read *); 205 int64_t (*seek_data)(struct archive_read *, int64_t, int); 206 int (*cleanup)(struct archive_read *); 207 int (*format_capabilties)(struct archive_read *); 208 int (*has_encrypted_entries)(struct archive_read *); 209 } formats[16]; 210 struct archive_format_descriptor *format; /* Active format. */ 211 212 /* 213 * Various information needed by archive_extract. 214 */ 215 struct archive_read_extract *extract; 216 int (*cleanup_archive_extract)(struct archive_read *); 217 218 /* 219 * Decryption passphrase. 220 */ 221 struct { 222 struct archive_read_passphrase *first; 223 struct archive_read_passphrase **last; 224 int candidate; 225 archive_passphrase_callback *callback; 226 void *client_data; 227 } passphrases; 228 }; 229 230 int __archive_read_register_format(struct archive_read *a, 231 void *format_data, 232 const char *name, 233 int (*bid)(struct archive_read *, int), 234 int (*options)(struct archive_read *, const char *, const char *), 235 int (*read_header)(struct archive_read *, struct archive_entry *), 236 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *), 237 int (*read_data_skip)(struct archive_read *), 238 int64_t (*seek_data)(struct archive_read *, int64_t, int), 239 int (*cleanup)(struct archive_read *), 240 int (*format_capabilities)(struct archive_read *), 241 int (*has_encrypted_entries)(struct archive_read *)); 242 243 int __archive_read_get_bidder(struct archive_read *a, 244 struct archive_read_filter_bidder **bidder); 245 246 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *); 247 const void *__archive_read_filter_ahead(struct archive_read_filter *, 248 size_t, ssize_t *); 249 int64_t __archive_read_seek(struct archive_read*, int64_t, int); 250 int64_t __archive_read_filter_seek(struct archive_read_filter *, int64_t, int); 251 int64_t __archive_read_consume(struct archive_read *, int64_t); 252 int64_t __archive_read_filter_consume(struct archive_read_filter *, int64_t); 253 int __archive_read_program(struct archive_read_filter *, const char *); 254 void __archive_read_free_filters(struct archive_read *); 255 struct archive_read_extract *__archive_read_get_extract(struct archive_read *); 256 257 258 /* 259 * Get a decryption passphrase. 260 */ 261 void __archive_read_reset_passphrase(struct archive_read *a); 262 const char * __archive_read_next_passphrase(struct archive_read *a); 263 #endif 264