contrib/libarchive-2.0/libarchive/archive_write_private.h

   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_write_private.h,v 1.1 2007/03/03 07:37:36 kientzle Exp $
  26  */
  27
  28 #ifndef ARCHIVE_WRITE_PRIVATE_H_INCLUDED
  29 #define ARCHIVE_WRITE_PRIVATE_H_INCLUDED
  30
  31 #include "archive.h"
  32 #include "archive_string.h"
  33 #include "archive_private.h"
  34
  35 struct archive_write {
  36         struct archive  archive;
  37
  38         struct archive_entry    *entry;
  39
  40         /* Dev/ino of the archive being read/written. */
  41         dev_t             skip_file_dev;
  42         ino_t             skip_file_ino;
  43
  44         /* Utility:  Pointer to a block of nulls. */
  45         const unsigned char     *nulls;
  46         size_t                   null_length;
  47
  48         /*
  49          * Used by archive_read_data() to track blocks and copy
  50          * data to client buffers, filling gaps with zero bytes.
  51          */
  52         const char       *read_data_block;
  53         off_t             read_data_offset;
  54         off_t             read_data_output_offset;
  55         size_t            read_data_remaining;
  56
  57         /* Callbacks to open/read/write/close archive stream. */
  58         archive_open_callback   *client_opener;
  59         archive_read_callback   *client_reader;
  60         archive_skip_callback   *client_skipper;
  61         archive_write_callback  *client_writer;
  62         archive_close_callback  *client_closer;
  63         void                    *client_data;
  64
  65         /*
  66          * Blocking information.  Note that bytes_in_last_block is
  67          * misleadingly named; I should find a better name.  These
  68          * control the final output from all compressors, including
  69          * compression_none.
  70          */
  71         int               bytes_per_block;
  72         int               bytes_in_last_block;
  73
  74         /*
  75          * These control whether data within a gzip/bzip2 compressed
  76          * stream gets padded or not.  If pad_uncompressed is set,
  77          * the data will be padded to a full block before being
  78          * compressed.  The pad_uncompressed_byte determines the value
  79          * that will be used for padding.  Note that these have no
  80          * effect on compression "none."
  81          */
  82         int               pad_uncompressed;
  83         int               pad_uncompressed_byte; /* TODO: Support this. */
  84
  85         /*
  86          * On write, the client just invokes an archive_write_set function
  87          * which sets up the data here directly.
  88          */
  89         void     *compression_data;             /* Data for (de)compressor. */
  90         int     (*compression_init)(struct archive_write *);    /* Initialize. */
  91         int     (*compression_finish)(struct archive_write *);
  92         int     (*compression_write)(struct archive_write *, const void *, size_t);
  93         /*
  94          * Read uses a peek/consume I/O model: the decompression code
  95          * returns a pointer to the requested block and advances the
  96          * file position only when requested by a consume call.  This
  97          * reduces copying and also simplifies look-ahead for format
  98          * detection.
  99          */
 100         ssize_t (*compression_read_ahead)(struct archive *,
 101                     const void **, size_t request);
 102         ssize_t (*compression_read_consume)(struct archive *, size_t);
 103         off_t (*compression_skip)(struct archive *, off_t);
 104
 105         /*
 106          * Format detection is mostly the same as compression
 107          * detection, with two significant differences: The bidders
 108          * use the read_ahead calls above to examine the stream rather
 109          * than having the supervisor hand them a block of data to
 110          * examine, and the auction is repeated for every header.
 111          * Winning bidders should set the archive_format and
 112          * archive_format_name appropriately.  Bid routines should
 113          * check archive_format and decline to bid if the format of
 114          * the last header was incompatible.
 115          *
 116          * Again, write support is considerably simpler because there's
 117          * no need for an auction.
 118          */
 119         int               archive_format;
 120         const char       *archive_format_name;
 121
 122         struct archive_format_descriptor {
 123                 int     (*bid)(struct archive *);
 124                 int     (*read_header)(struct archive *, struct archive_entry *);
 125                 int     (*read_data)(struct archive *, const void **, size_t *, off_t *);
 126                 int     (*read_data_skip)(struct archive *);
 127                 int     (*cleanup)(struct archive *);
 128                 void     *format_data;  /* Format-specific data for readers. */
 129         }       formats[8];
 130         struct archive_format_descriptor        *format; /* Active format. */
 131
 132         /*
 133          * Storage for format-specific data.  Note that there can be
 134          * multiple format readers active at one time, so we need to
 135          * allow for multiple format readers to have their data
 136          * available.  The pformat_data slot here is the solution: on
 137          * read, it is guaranteed to always point to a void* variable
 138          * that the format can use.
 139          */
 140         void    **pformat_data;         /* Pointer to current format_data. */
 141         void     *format_data;          /* Used by writers. */
 142
 143         /*
 144          * Pointers to format-specific functions for writing.  They're
 145          * initialized by archive_write_set_format_XXX() calls.
 146          */
 147         int     (*format_init)(struct archive_write *);
 148         int     (*format_finish)(struct archive_write *);
 149         int     (*format_destroy)(struct archive_write *);
 150         int     (*format_finish_entry)(struct archive_write *);
 151         int     (*format_write_header)(struct archive_write *,
 152                     struct archive_entry *);
 153         ssize_t (*format_write_data)(struct archive_write *,
 154                     const void *buff, size_t);
 155
 156         /*
 157          * Various information needed by archive_extract.
 158          */
 159         struct extract           *extract;
 160         int                     (*cleanup_archive_extract)(struct archive *);
 161 };
 162
 163 /*
 164  * Utility function to format a USTAR header into a buffer.  If
 165  * "strict" is set, this tries to create the absolutely most portable
 166  * version of a ustar header.  If "strict" is set to 0, then it will
 167  * relax certain requirements.
 168  *
 169  * Generally, format-specific declarations don't belong in this
 170  * header; this is a rare example of a function that is shared by
 171  * two very similar formats (ustar and pax).
 172  */
 173 int
 174 __archive_write_format_header_ustar(struct archive_write *, char buff[512],
 175     struct archive_entry *, int tartype, int strict);
 176
 177 #endif