pcompress/archive/libarchive-3.1.2/libarchive/archive_read_private.h
2014-09-11 18:34:43 +05:30

244 lines
8.7 KiB
C

/*-
* Copyright (c) 2003-2007 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD: head/lib/libarchive/archive_read_private.h 201088 2009-12-28 02:18:55Z kientzle $
*/
#ifndef __LIBARCHIVE_BUILD
#error This header is only to be used internally to libarchive.
#endif
#ifndef ARCHIVE_READ_PRIVATE_H_INCLUDED
#define ARCHIVE_READ_PRIVATE_H_INCLUDED
#include "archive.h"
#include "archive_string.h"
#include "archive_private.h"
struct archive_read;
struct archive_read_filter_bidder;
struct archive_read_filter;
/*
* How bidding works for filters:
* * The bid manager initializes the client-provided reader as the
* first filter.
* * It invokes the bidder for each registered filter with the
* current head filter.
* * The bidders can use archive_read_filter_ahead() to peek ahead
* at the incoming data to compose their bids.
* * The bid manager creates a new filter structure for the winning
* bidder and gives the winning bidder a chance to initialize it.
* * The new filter becomes the new top filter and we repeat the
* process.
* This ends only when no bidder provides a non-zero bid. Then
* we perform a similar dance with the registered format handlers.
*/
struct archive_read_filter_bidder {
/* Configuration data for the bidder. */
void *data;
/* Name of the filter */
const char *name;
/* Taste the upstream filter to see if we handle this. */
int (*bid)(struct archive_read_filter_bidder *,
struct archive_read_filter *);
/* Initialize a newly-created filter. */
int (*init)(struct archive_read_filter *);
/* Set an option for the filter bidder. */
int (*options)(struct archive_read_filter_bidder *,
const char *key, const char *value);
/* Release the bidder's configuration data. */
int (*free)(struct archive_read_filter_bidder *);
};
/*
* This structure is allocated within the archive_read core
* and initialized by archive_read and the init() method of the
* corresponding bidder above.
*/
struct archive_read_filter {
int64_t position;
/* Essentially all filters will need these values, so
* just declare them here. */
struct archive_read_filter_bidder *bidder; /* My bidder. */
struct archive_read_filter *upstream; /* Who I read from. */
struct archive_read *archive; /* Associated archive. */
/* Open a block for reading */
int (*open)(struct archive_read_filter *self);
/* Return next block. */
ssize_t (*read)(struct archive_read_filter *, const void **);
/* Skip forward this many bytes. */
int64_t (*skip)(struct archive_read_filter *self, int64_t request);
/* Seek to an absolute location. */
int64_t (*seek)(struct archive_read_filter *self, int64_t offset, int whence);
/* Close (just this filter) and free(self). */
int (*close)(struct archive_read_filter *self);
/* Function that handles switching from reading one block to the next/prev */
int (*sswitch)(struct archive_read_filter *self, unsigned int iindex);
/* My private data. */
void *data;
const char *name;
int code;
/* Used by reblocking logic. */
char *buffer;
size_t buffer_size;
char *next; /* Current read location. */
size_t avail; /* Bytes in my buffer. */
const void *client_buff; /* Client buffer information. */
size_t client_total;
const char *client_next;
size_t client_avail;
char end_of_file;
char closed;
char fatal;
};
/*
* The client looks a lot like a filter, so we just wrap it here.
*
* TODO: Make archive_read_filter and archive_read_client identical so
* that users of the library can easily register their own
* transformation filters. This will probably break the API/ABI and
* so should be deferred at least until libarchive 3.0.
*/
struct archive_read_data_node {
int64_t begin_position;
int64_t total_size;
void *data;
};
struct archive_read_client {
archive_open_callback *opener;
archive_read_callback *reader;
archive_skip_callback *skipper;
archive_seek_callback *seeker;
archive_close_callback *closer;
archive_switch_callback *switcher;
unsigned int nodes;
unsigned int cursor;
int64_t position;
struct archive_read_data_node *dataset;
};
struct archive_read {
struct archive archive;
struct archive_entry *entry;
/* Dev/ino of the archive being read/written. */
int skip_file_set;
int64_t skip_file_dev;
int64_t skip_file_ino;
/*
* Used by archive_read_data() to track blocks and copy
* data to client buffers, filling gaps with zero bytes.
*/
const char *read_data_block;
int64_t read_data_offset;
int64_t read_data_output_offset;
size_t read_data_remaining;
/*
* Used by formats/filters to determine the amount of data
* requested from a call to archive_read_data(). This is only
* useful when the format/filter has seek support.
*/
char read_data_is_posix_read;
size_t read_data_requested;
/* Callbacks to open/read/write/close client archive streams. */
struct archive_read_client client;
/* Registered filter bidders. */
struct archive_read_filter_bidder bidders[14];
/* Last filter in chain */
struct archive_read_filter *filter;
/* Whether to bypass filter bidding process */
int bypass_filter_bidding;
/* File offset of beginning of most recently-read header. */
int64_t header_position;
/* Nodes and offsets of compressed data block */
unsigned int data_start_node;
unsigned int data_end_node;
/*
* Format detection is mostly the same as compression
* detection, with one significant difference: The bidders
* use the read_ahead calls above to examine the stream rather
* than having the supervisor hand them a block of data to
* examine.
*/
struct archive_format_descriptor {
void *data;
const char *name;
int (*bid)(struct archive_read *, int best_bid);
int (*options)(struct archive_read *, const char *key,
const char *value);
int (*read_header)(struct archive_read *, struct archive_entry *);
int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *);
int (*read_data_skip)(struct archive_read *);
int64_t (*seek_data)(struct archive_read *, int64_t, int);
int (*cleanup)(struct archive_read *);
} formats[16];
struct archive_format_descriptor *format; /* Active format. */
/*
* Various information needed by archive_extract.
*/
struct extract *extract;
int (*cleanup_archive_extract)(struct archive_read *);
};
int __archive_read_register_format(struct archive_read *a,
void *format_data,
const char *name,
int (*bid)(struct archive_read *, int),
int (*options)(struct archive_read *, const char *, const char *),
int (*read_header)(struct archive_read *, struct archive_entry *),
int (*read_data)(struct archive_read *, const void **, size_t *, int64_t *),
int (*read_data_skip)(struct archive_read *),
int64_t (*seek_data)(struct archive_read *, int64_t, int),
int (*cleanup)(struct archive_read *));
int __archive_read_get_bidder(struct archive_read *a,
struct archive_read_filter_bidder **bidder);
const void *__archive_read_ahead(struct archive_read *, size_t, ssize_t *);
const void *__archive_read_filter_ahead(struct archive_read_filter *,
size_t, ssize_t *);
int64_t __archive_read_seek(struct archive_read*, int64_t, int);
int64_t __archive_read_filter_seek(struct archive_read_filter *, int64_t, int);
int64_t __archive_read_consume(struct archive_read *, int64_t);
int64_t __archive_read_filter_consume(struct archive_read_filter *, int64_t);
int __archive_read_program(struct archive_read_filter *, const char *);
void __archive_read_free_filters(struct archive_read *);
int __archive_read_close_filters(struct archive_read *);
#endif