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 initializes the client-provided reader as the 46 * first filter. 47 * * It invokes the bidder for each registered filter with the 48 * current head filter. 49 * * The bidders can use archive_read_filter_ahead() to peek ahead 50 * at the incoming data to compose their bids. 51 * * The bid manager creates a new filter structure for the winning 52 * bidder and gives the winning bidder a chance to initialize it. 53 * * The new filter becomes the new top filter and we repeat the 54 * process. 55 * This ends only when no bidder provides a non-zero bid. Then 56 * we perform a similar dance with the registered format handlers. 57 */ 58 struct archive_read_filter_bidder { 59 /* Configuration data for the bidder. */ 60 void *data; 61 /* Taste the upstream filter to see if we handle this. */ 62 int (*bid)(struct archive_read_filter_bidder *, 63 struct archive_read_filter *); 64 /* Initialize a newly-created filter. */ 65 int (*init)(struct archive_read_filter *); 66 /* Set an option for the filter bidder. */ 67 int (*options)(struct archive_read_filter_bidder *, 68 const char *key, const char *value); 69 /* Release the bidder's configuration data. */ 70 int (*free)(struct archive_read_filter_bidder *); 71 }; 72 73 /* 74 * This structure is allocated within the archive_read core 75 * and initialized by archive_read and the init() method of the 76 * corresponding bidder above. 77 */ 78 struct archive_read_filter { 79 int64_t position; 80 /* Essentially all filters will need these values, so 81 * just declare them here. */ 82 struct archive_read_filter_bidder *bidder; /* My bidder. */ 83 struct archive_read_filter *upstream; /* Who I read from. */ 84 struct archive_read *archive; /* Associated archive. */ 85 /* Return next block. */ 86 ssize_t (*read)(struct archive_read_filter *, const void **); 87 /* Skip forward this many bytes. */ 88 int64_t (*skip)(struct archive_read_filter *self, int64_t request); 89 /* Seek to an absolute location. */ 90 int64_t (*seek)(struct archive_read_filter *self, int64_t offset, int whence); 91 /* Close (just this filter) and free(self). */ 92 int (*close)(struct archive_read_filter *self); 93 /* My private data. */ 94 void *data; 95 96 const char *name; 97 int code; 98 99 /* Used by reblocking logic. */ 100 char *buffer; 101 size_t buffer_size; 102 char *next; /* Current read location. */ 103 size_t avail; /* Bytes in my buffer. */ 104 const void *client_buff; /* Client buffer information. */ 105 size_t client_total; 106 const char *client_next; 107 size_t client_avail; 108 char end_of_file; 109 char closed; 110 char fatal; 111 }; 112 113 /* 114 * The client looks a lot like a filter, so we just wrap it here. 115 * 116 * TODO: Make archive_read_filter and archive_read_client identical so 117 * that users of the library can easily register their own 118 * transformation filters. This will probably break the API/ABI and 119 * so should be deferred at least until libarchive 3.0. 120 */ 121 struct archive_read_client { 122 archive_open_callback *opener; 123 archive_read_callback *reader; 124 archive_skip_callback *skipper; 125 archive_seek_callback *seeker; 126 archive_close_callback *closer; 127 void *data; 128 }; 129 130 struct archive_read { 131 struct archive archive; 132 133 struct archive_entry *entry; 134 135 /* Dev/ino of the archive being read/written. */ 136 int skip_file_set; 137 dev_t skip_file_dev; 138 ino_t skip_file_ino; 139 140 /* 141 * Used by archive_read_data() to track blocks and copy 142 * data to client buffers, filling gaps with zero bytes. 143 */ 144 const char *read_data_block; 145 int64_t read_data_offset; 146 int64_t read_data_output_offset; 147 size_t read_data_remaining; 148 149 /* Callbacks to open/read/write/close client archive stream. */ 150 struct archive_read_client client; 151 152 /* Registered filter bidders. */ 153 struct archive_read_filter_bidder bidders[9]; 154 155 /* Last filter in chain */ 156 struct archive_read_filter *filter; 157 158 /* File offset of beginning of most recently-read header. */ 159 int64_t header_position; 160 161 /* 162 * Format detection is mostly the same as compression 163 * detection, with one significant difference: The bidders 164 * use the read_ahead calls above to examine the stream rather 165 * than having the supervisor hand them a block of data to 166 * examine. 167 */ 168 169 struct archive_format_descriptor { 170 void *data; 171 const char *name; 172 int (*bid)(struct archive_read *, int best_bid); 173 int (*options)(struct archive_read *, const char *key, 174 const char *value); 175 int (*read_header)(struct archive_read *, struct archive_entry *); 176 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *); 177 int (*read_data_skip)(struct archive_read *); 178 int (*cleanup)(struct archive_read *); 179 } formats[16]; 180 struct archive_format_descriptor *format; /* Active format. */ 181 182 /* 183 * Various information needed by archive_extract. 184 */ 185 struct extract *extract; 186 int (*cleanup_archive_extract)(struct archive_read *); 187 }; 188 189 int __archive_read_register_format(struct archive_read *a, 190 void *format_data, 191 const char *name, 192 int (*bid)(struct archive_read *, int), 193 int (*options)(struct archive_read *, const char *, const char *), 194 int (*read_header)(struct archive_read *, struct archive_entry *), 195 int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *), 196 int (*read_data_skip)(struct archive_read *), 197 int (*cleanup)(struct archive_read *)); 198 199 int __archive_read_get_bidder(struct archive_read *a, 200 struct archive_read_filter_bidder **bidder); 201 202 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *); 203 const void *__archive_read_filter_ahead(struct archive_read_filter *, 204 size_t, ssize_t *); 205 int64_t __archive_read_seek(struct archive_read*, int64_t, int); 206 int64_t __archive_read_filter_seek(struct archive_read_filter *, int64_t, int); 207 int64_t __archive_read_consume(struct archive_read *, int64_t); 208 int64_t __archive_read_filter_consume(struct archive_read_filter *, int64_t); 209 int __archive_read_program(struct archive_read_filter *, const char *); 210 #endif 211