facbbae9f9
This is the last phase of the "big decompression refactor" that puts a lazy reblocking layer between each pair of read filters. I've also changed the terminology for this area---the two kinds of objects are now called "read filters" and "read filter bidders"---and moved ownership of these objects to the archive_read core. This greatly simplifies implementing new read filters, which can now use peek/consume I/O semantics both for bidding (arbitrary look-ahead!) and for reading streams (look-ahead simplifies handling concatenated streams, for instance). The first merge here is the overhaul proper; the remainder are small fixes to correct errors in the initial implementation.
186 lines
6.5 KiB
C
186 lines
6.5 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.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#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 reads the first block from the current source.
|
|
* * It shows that block to each registered bidder.
|
|
* * 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 top filter in the archive_read structure
|
|
* and we repeat the process.
|
|
* This ends only when no bidder provides a non-zero bid.
|
|
*/
|
|
struct archive_read_filter_bidder {
|
|
/* Configuration data for the bidder. */
|
|
void *data;
|
|
/* 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 *);
|
|
/* 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 {
|
|
/* 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. */
|
|
/* 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);
|
|
/* Close (just this filter) and free(self). */
|
|
int (*close)(struct archive_read_filter *self);
|
|
/* 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;
|
|
int64_t position;
|
|
char end_of_file;
|
|
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_client {
|
|
archive_read_callback *reader;
|
|
archive_skip_callback *skipper;
|
|
archive_close_callback *closer;
|
|
};
|
|
|
|
struct archive_read {
|
|
struct archive archive;
|
|
|
|
struct archive_entry *entry;
|
|
|
|
/* Dev/ino of the archive being read/written. */
|
|
dev_t skip_file_dev;
|
|
ino_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;
|
|
off_t read_data_offset;
|
|
off_t read_data_output_offset;
|
|
size_t read_data_remaining;
|
|
|
|
/* Callbacks to open/read/write/close client archive stream. */
|
|
struct archive_read_client client;
|
|
|
|
/* Registered filter bidders. */
|
|
struct archive_read_filter_bidder bidders[8];
|
|
|
|
/* Last filter in chain */
|
|
struct archive_read_filter *filter;
|
|
|
|
/* File offset of beginning of most recently-read header. */
|
|
off_t header_position;
|
|
|
|
/*
|
|
* 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;
|
|
int (*bid)(struct archive_read *);
|
|
int (*read_header)(struct archive_read *, struct archive_entry *);
|
|
int (*read_data)(struct archive_read *, const void **, size_t *, off_t *);
|
|
int (*read_data_skip)(struct archive_read *);
|
|
int (*cleanup)(struct archive_read *);
|
|
} formats[8];
|
|
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,
|
|
int (*bid)(struct archive_read *),
|
|
int (*read_header)(struct archive_read *, struct archive_entry *),
|
|
int (*read_data)(struct archive_read *, const void **, size_t *, off_t *),
|
|
int (*read_data_skip)(struct archive_read *),
|
|
int (*cleanup)(struct archive_read *));
|
|
|
|
struct archive_read_filter_bidder
|
|
*__archive_read_get_bidder(struct archive_read *a);
|
|
|
|
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 *);
|
|
ssize_t __archive_read_consume(struct archive_read *, size_t);
|
|
ssize_t __archive_read_filter_consume(struct archive_read_filter *, size_t);
|
|
int64_t __archive_read_skip(struct archive_read *, int64_t);
|
|
int64_t __archive_read_filter_skip(struct archive_read_filter *, int64_t);
|
|
#endif
|