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* Copyright (c) 2003-2007 Tim Kientzle
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#include "archive_platform.h"
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__FBSDID("$FreeBSD: src/lib/libarchive/archive_read_open_memory.c,v 1.6 2007/07/06 15:51:59 kientzle Exp $");
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* Glue to read an archive from a block of memory.
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* This is mostly a huge help in building test harnesses;
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* test programs can build archives in memory and read them
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* back again without having to mess with files on disk.
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struct read_memory_data {
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unsigned char *buffer;
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static int memory_read_close(struct archive *, void *);
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static int memory_read_open(struct archive *, void *);
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#if ARCHIVE_API_VERSION < 2
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static ssize_t memory_read_skip(struct archive *, void *, size_t request);
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static off_t memory_read_skip(struct archive *, void *, off_t request);
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static ssize_t memory_read(struct archive *, void *, const void **buff);
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archive_read_open_memory(struct archive *a, void *buff, size_t size)
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return archive_read_open_memory2(a, buff, size, size);
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* Don't use _open_memory2() in production code; the archive_read_open_memory()
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* version is the one you really want. This is just here so that
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* test harnesses can exercise block operations inside the library.
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archive_read_open_memory2(struct archive *a, void *buff,
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size_t size, size_t read_size)
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struct read_memory_data *mine;
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mine = (struct read_memory_data *)malloc(sizeof(*mine));
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archive_set_error(a, ENOMEM, "No memory");
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return (ARCHIVE_FATAL);
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memset(mine, 0, sizeof(*mine));
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mine->buffer = (unsigned char *)buff;
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mine->end = mine->buffer + size;
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mine->read_size = read_size;
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return (archive_read_open2(a, mine, memory_read_open,
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memory_read, memory_read_skip, memory_read_close));
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* There's nothing to open.
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memory_read_open(struct archive *a, void *client_data)
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(void)client_data; /* UNUSED */
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* This is scary simple: Just advance a pointer. Limiting
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* to read_size is not technically necessary, but it exercises
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* more of the internal logic when used with a small block size
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* in a test harness. Production use should not specify a block
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* size; then this is much faster.
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memory_read(struct archive *a, void *client_data, const void **buff)
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struct read_memory_data *mine = (struct read_memory_data *)client_data;
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(void)a; /* UNUSED */
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*buff = mine->buffer;
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size = mine->end - mine->buffer;
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if (size > mine->read_size)
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size = mine->read_size;
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mine->buffer += size;
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* Advancing is just as simple. Again, this is doing more than
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* necessary in order to better exercise internal code when used
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#if ARCHIVE_API_VERSION < 2
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memory_read_skip(struct archive *a, void *client_data, size_t skip)
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memory_read_skip(struct archive *a, void *client_data, off_t skip)
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struct read_memory_data *mine = (struct read_memory_data *)client_data;
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(void)a; /* UNUSED */
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if ((off_t)skip > (off_t)(mine->end - mine->buffer))
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skip = mine->end - mine->buffer;
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/* Round down to block size. */
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skip /= mine->read_size;
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skip *= mine->read_size;
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mine->buffer += skip;
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* Close is just cleaning up our one small bit of data.
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memory_read_close(struct archive *a, void *client_data)
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struct read_memory_data *mine = (struct read_memory_data *)client_data;
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(void)a; /* UNUSED */