/* simple.c -- the annotated simple example program for the LZO library

   This file is part of the LZO real-time data compression library.

   Copyright (C) 1996-2014 Markus Franz Xaver Johannes Oberhumer

   All Rights Reserved.

   The LZO library is free software; you can redistribute it and/or

   modify it under the terms of the GNU General Public License as

   published by the Free Software Foundation; either version 2 of

   the License, or (at your option) any later version.

   The LZO library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with the LZO library; see the file COPYING.

   If not, write to the Free Software Foundation, Inc.,

   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

   Markus F.X.J. Oberhumer

   <markus@oberhumer.com>

   http://www.oberhumer.com/opensource/lzo/

 */

/*************************************************************************

// This program shows the basic usage of the LZO library.

// We will compress a block of data and decompress again.

//

// See also LZO.FAQ

**************************************************************************/

/* We will be using the LZO1X-1 algorithm, so we have

 * to include <lzo1x.h>

 */

#include "lzo/lzoconf.h"

#include "lzo/lzo1x.h"

/* portability layer */

static const char *progname = NULL;

#define WANT_LZO_MALLOC 1

#define WANT_XMALLOC 1

#include "examples/portab.h"

/* We want to compress the data block at 'in' with length 'IN_LEN' to

 * the block at 'out'. Because the input block may be incompressible,

 * we must provide a little more output space in case that compression

 * is not possible.

 */

#ifndef IN_LEN

#define IN_LEN      (128*1024L)

#endif

#define OUT_LEN     (IN_LEN + IN_LEN / 16 + 64 + 3)

/*************************************************************************

//

**************************************************************************/

int __lzo_cdecl_main main(int argc, char *argv[])

{

    int r;

    lzo_bytep in;

    lzo_bytep out;

    lzo_voidp wrkmem;

    lzo_uint in_len;

    lzo_uint out_len;

    lzo_uint new_len;

    if (argc < 0 && argv == NULL)   /* avoid warning about unused args */

        return 0;

    printf("\nLZO real-time data compression library (v%s, %s).\n",

           lzo_version_string(), lzo_version_date());

    printf("Copyright (C) 1996-2014 Markus Franz Xaver Johannes Oberhumer\nAll Rights Reserved.\n\n");

/*

 * Step 1: initialize the LZO library

 */

    if (lzo_init() != LZO_E_OK)

    {

        printf("internal error - lzo_init() failed !!!\n");

        printf("(this usually indicates a compiler bug - try recompiling\nwithout optimizations, and enable '-DLZO_DEBUG' for diagnostics)\n");

        return 4;

    }

/*

 * Step 2: allocate blocks and the work-memory

 */

    in = (lzo_bytep) xmalloc(IN_LEN);

    out = (lzo_bytep) xmalloc(OUT_LEN);

    wrkmem = (lzo_voidp) xmalloc(LZO1X_1_MEM_COMPRESS);

    if (in == NULL || out == NULL || wrkmem == NULL)

    {

        printf("out of memory\n");

        return 3;

    }

/*

 * Step 3: prepare the input block that will get compressed.

 *         We just fill it with zeros in this example program,

 *         but you would use your real-world data here.

 */

    in_len = IN_LEN;

    lzo_memset(in,0,in_len);

/*

 * Step 4: compress from 'in' to 'out' with LZO1X-1

 */

    r = lzo1x_1_compress(in, in_len, out, &out_len, wrkmem);

    if (r == LZO_E_OK)

        printf("compressed %lu bytes into %lu bytes\n",

               (unsigned long) in_len, (unsigned long) out_len);

    else

    {

        /* this should NEVER happen */

        printf("internal error - compression failed: %d\n", r);

        return 2;

    }

    /* check for an incompressible block */

    if (out_len >= in_len)

    {

        printf("This block contains incompressible data.\n");

        return 0;

    }

/*

 * Step 5: decompress again, now going from 'out' to 'in'

 */

    new_len = in_len;

    r = lzo1x_decompress(out, out_len, in, &new_len, NULL);

    if (r == LZO_E_OK && new_len == in_len)

        printf("decompressed %lu bytes back into %lu bytes\n",

               (unsigned long) out_len, (unsigned long) in_len);

    else

    {

        /* this should NEVER happen */

        printf("internal error - decompression failed: %d\n", r);

        return 1;

    }

    lzo_free(wrkmem);

    lzo_free(out);

    lzo_free(in);

    printf("Simple compression test passed.\n");

    return 0;

}

/* vim:set ts=4 sw=4 et: */