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: src/lib/libarchive/archive_read_private.h,v 1.7 2008/12/06 06:45:15 kientzle Exp $ 26 */ 27 28 #ifndef ARCHIVE_READ_PRIVATE_H_INCLUDED 29 #define ARCHIVE_READ_PRIVATE_H_INCLUDED 30 31 #include "archive.h" 32 #include "archive_string.h" 33 #include "archive_private.h" 34 35 struct archive_read; 36 struct archive_read_filter_bidder; 37 struct archive_read_filter; 38 39 /* 40 * How bidding works for filters: 41 * * The bid manager reads the first block from the current source. 42 * * It shows that block to each registered bidder. 43 * * The bid manager creates a new filter structure for the winning 44 * bidder and gives the winning bidder a chance to initialize it. 45 * * The new filter becomes the top filter in the archive_read structure 46 * and we repeat the process. 47 * This ends only when no bidder provides a non-zero bid. 48 */ 49 struct archive_read_filter_bidder { 50 /* Configuration data for the bidder. */ 51 void *data; 52 /* Taste the upstream filter to see if we handle this. */ 53 int (*bid)(struct archive_read_filter_bidder *, 54 struct archive_read_filter *); 55 /* Initialize a newly-created filter. */ 56 int (*init)(struct archive_read_filter *); 57 /* Set an option for the filter bidder. */ 58 int (*options)(struct archive_read_filter_bidder *, 59 const char *key, const char *value); 60 /* Release the bidder's configuration data. */ 61 int (*free)(struct archive_read_filter_bidder *); 62 }; 63 64 /* 65 * This structure is allocated within the archive_read core 66 * and initialized by archive_read and the init() method of the 67 * corresponding bidder above. 68 */ 69 struct archive_read_filter { 70 /* Essentially all filters will need these values, so 71 * just declare them here. */ 72 struct archive_read_filter_bidder *bidder; /* My bidder. */ 73 struct archive_read_filter *upstream; /* Who I read from. */ 74 struct archive_read *archive; /* Associated archive. */ 75 /* Return next block. */ 76 ssize_t (*read)(struct archive_read_filter *, const void **); 77 /* Skip forward this many bytes. */ 78 int64_t (*skip)(struct archive_read_filter *self, int64_t request); 79 /* Close (just this filter) and free(self). */ 80 int (*close)(struct archive_read_filter *self); 81 /* My private data. */ 82 void *data; 83 84 const char *name; 85 int code; 86 87 /* Used by reblocking logic. */ 88 char *buffer; 89 size_t buffer_size; 90 char *next; /* Current read location. */ 91 size_t avail; /* Bytes in my buffer. */ 92 const void *client_buff; /* Client buffer information. */ 93 size_t client_total; 94 const char *client_next; 95 size_t client_avail; 96 int64_t position; 97 char end_of_file; 98 char fatal; 99 }; 100 101 /* 102 * The client looks a lot like a filter, so we just wrap it here. 103 * 104 * TODO: Make archive_read_filter and archive_read_client identical so 105 * that users of the library can easily register their own 106 * transformation filters. This will probably break the API/ABI and 107 * so should be deferred at least until libarchive 3.0. 108 */ 109 struct archive_read_client { 110 archive_read_callback *reader; 111 archive_skip_callback *skipper; 112 archive_close_callback *closer; 113 }; 114 115 struct archive_read { 116 struct archive archive; 117 118 struct archive_entry *entry; 119 120 /* Dev/ino of the archive being read/written. */ 121 dev_t skip_file_dev; 122 ino_t skip_file_ino; 123 124 /* 125 * Used by archive_read_data() to track blocks and copy 126 * data to client buffers, filling gaps with zero bytes. 127 */ 128 const char *read_data_block; 129 off_t read_data_offset; 130 off_t read_data_output_offset; 131 size_t read_data_remaining; 132 133 /* Callbacks to open/read/write/close client archive stream. */ 134 struct archive_read_client client; 135 136 /* Registered filter bidders. */ 137 struct archive_read_filter_bidder bidders[8]; 138 139 /* Last filter in chain */ 140 struct archive_read_filter *filter; 141 142 /* File offset of beginning of most recently-read header. */ 143 off_t header_position; 144 145 /* 146 * Format detection is mostly the same as compression 147 * detection, with one significant difference: The bidders 148 * use the read_ahead calls above to examine the stream rather 149 * than having the supervisor hand them a block of data to 150 * examine. 151 */ 152 153 struct archive_format_descriptor { 154 void *data; 155 const char *name; 156 int (*bid)(struct archive_read *); 157 int (*options)(struct archive_read *, const char *key, 158 const char *value); 159 int (*read_header)(struct archive_read *, struct archive_entry *); 160 int (*read_data)(struct archive_read *, const void **, size_t *, off_t *); 161 int (*read_data_skip)(struct archive_read *); 162 int (*cleanup)(struct archive_read *); 163 } formats[8]; 164 struct archive_format_descriptor *format; /* Active format. */ 165 166 /* 167 * Various information needed by archive_extract. 168 */ 169 struct extract *extract; 170 int (*cleanup_archive_extract)(struct archive_read *); 171 }; 172 173 int __archive_read_register_format(struct archive_read *a, 174 void *format_data, 175 const char *name, 176 int (*bid)(struct archive_read *), 177 int (*options)(struct archive_read *, const char *, const char *), 178 int (*read_header)(struct archive_read *, struct archive_entry *), 179 int (*read_data)(struct archive_read *, const void **, size_t *, off_t *), 180 int (*read_data_skip)(struct archive_read *), 181 int (*cleanup)(struct archive_read *)); 182 183 struct archive_read_filter_bidder 184 *__archive_read_get_bidder(struct archive_read *a); 185 186 const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *); 187 const void *__archive_read_filter_ahead(struct archive_read_filter *, 188 size_t, ssize_t *); 189 ssize_t __archive_read_consume(struct archive_read *, size_t); 190 ssize_t __archive_read_filter_consume(struct archive_read_filter *, size_t); 191 int64_t __archive_read_skip(struct archive_read *, int64_t); 192 int64_t __archive_read_filter_skip(struct archive_read_filter *, int64_t); 193 int __archive_read_program(struct archive_read_filter *, const char *); 194 #endif 195