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 ARCHIVE_READ_PRIVATE_H_INCLUDED 29 #define ARCHIVE_READ_PRIVATE_H_INCLUDED 30 31 #ifndef __LIBARCHIVE_BUILD 32 #ifndef __LIBARCHIVE_TEST 33 #error This header is only to be used internally to libarchive. 34 #endif 35 #endif 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 /* Read any header metadata if available. */ 102 int (*read_header)(struct archive_read_filter *self, struct archive_entry *entry); 103 /* My private data. */ 104 void *data; 105 106 const char *name; 107 int code; 108 109 /* Used by reblocking logic. */ 110 char *buffer; 111 size_t buffer_size; 112 char *next; /* Current read location. */ 113 size_t avail; /* Bytes in my buffer. */ 114 const void *client_buff; /* Client buffer information. */ 115 size_t client_total; 116 const char *client_next; 117 size_t client_avail; 118 char end_of_file; 119 char closed; 120 char fatal; 121 }; 122 123 /* 124 * The client looks a lot like a filter, so we just wrap it here. 125 * 126 * TODO: Make archive_read_filter and archive_read_client identical so 127 * that users of the library can easily register their own 128 * transformation filters. This will probably break the API/ABI and 129 * so should be deferred at least until libarchive 3.0. 130 */ 131 struct archive_read_data_node { 132 int64_t begin_position; 133 int64_t total_size; 134 void *data; 135 }; 136 struct archive_read_client { 137 archive_open_callback *opener; 138 archive_read_callback *reader; 139 archive_skip_callback *skipper; 140 archive_seek_callback *seeker; 141 archive_close_callback *closer; 142 archive_switch_callback *switcher; 143 unsigned int nodes; 144 unsigned int cursor; 145 int64_t position; 146 struct archive_read_data_node *dataset; 147 }; 148 struct archive_read_passphrase { 149 char *passphrase; 150 struct archive_read_passphrase *next; 151 }; 152 153 struct archive_read_extract { 154 struct archive *ad; /* archive_write_disk object */ 155 156 /* Progress function invoked during extract. */ 157 void (*extract_progress)(void *); 158 void *extract_progress_user_data; 159 }; 160 161 struct archive_read { 162 struct archive archive; 163 164 struct archive_entry *entry; 165 166 /* Dev/ino of the archive being read/written. */ 167 int skip_file_set; 168 int64_t skip_file_dev; 169 int64_t skip_file_ino; 170 171 /* Callbacks to open/read/write/close client archive streams. */ 172 struct archive_read_client client; 173 174 /* Registered filter bidders. */ 175 struct archive_read_filter_bidder bidders[16]; 176 177 /* Last filter in chain */ 178 struct archive_read_filter *filter; 179 180 /* Whether to bypass filter bidding process */ 181 int bypass_filter_bidding; 182 183 /* File offset of beginning of most recently-read header. */ 184 int64_t header_position; 185 186 /* Nodes and offsets of compressed data block */ 187 unsigned int data_start_node; 188 unsigned int data_end_node; 189 190 /* 191 * Format detection is mostly the same as compression 192 * detection, with one significant difference: The bidders 193 * use the read_ahead calls above to examine the stream rather 194 * than having the supervisor hand them a block of data to 195 * examine. 196 */ 197 198 struct archive_format_descriptor { 199 void *data; 200 const char *name; 201 int (*bid)(struct archive_read *, int best_bid); 202 int (*options)(struct archive_read *, const char *key, 203 const char *value); 204 int (*read_header)(struct archive_read *, struct archive_entry *); 205 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *); 206 int (*read_data_skip)(struct archive_read *); 207 int64_t (*seek_data)(struct archive_read *, int64_t, int); 208 int (*cleanup)(struct archive_read *); 209 int (*format_capabilties)(struct archive_read *); 210 int (*has_encrypted_entries)(struct archive_read *); 211 } formats[16]; 212 struct archive_format_descriptor *format; /* Active format. */ 213 214 /* 215 * Various information needed by archive_extract. 216 */ 217 struct archive_read_extract *extract; 218 int (*cleanup_archive_extract)(struct archive_read *); 219 220 /* 221 * Decryption passphrase. 222 */ 223 struct { 224 struct archive_read_passphrase *first; 225 struct archive_read_passphrase **last; 226 int candidate; 227 archive_passphrase_callback *callback; 228 void *client_data; 229 } passphrases; 230 }; 231 232 int __archive_read_register_format(struct archive_read *a, 233 void *format_data, 234 const char *name, 235 int (*bid)(struct archive_read *, int), 236 int (*options)(struct archive_read *, const char *, const char *), 237 int (*read_header)(struct archive_read *, struct archive_entry *), 238 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *), 239 int (*read_data_skip)(struct archive_read *), 240 int64_t (*seek_data)(struct archive_read *, int64_t, int), 241 int (*cleanup)(struct archive_read *), 242 int (*format_capabilities)(struct archive_read *), 243 int (*has_encrypted_entries)(struct archive_read *)); 244 245 int __archive_read_get_bidder(struct archive_read *a, 246 struct archive_read_filter_bidder **bidder); 247 248 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *); 249 const void *__archive_read_filter_ahead(struct archive_read_filter *, 250 size_t, ssize_t *); 251 int64_t __archive_read_seek(struct archive_read*, int64_t, int); 252 int64_t __archive_read_filter_seek(struct archive_read_filter *, int64_t, int); 253 int64_t __archive_read_consume(struct archive_read *, int64_t); 254 int64_t __archive_read_filter_consume(struct archive_read_filter *, int64_t); 255 int __archive_read_header(struct archive_read *, struct archive_entry *); 256 int __archive_read_program(struct archive_read_filter *, const char *); 257 void __archive_read_free_filters(struct archive_read *); 258 struct archive_read_extract *__archive_read_get_extract(struct archive_read *); 259 260 261 /* 262 * Get a decryption passphrase. 263 */ 264 void __archive_read_reset_passphrase(struct archive_read *a); 265 const char * __archive_read_next_passphrase(struct archive_read *a); 266 #endif 267