lzo-2.03/examples/dict.c

/* dict.c -- example program: how to use preset dictionaries

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

   Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
   Copyright (C) 1996 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 how to use preset dictionaries.
//
// Please study LZO.FAQ and simple.c first.
**************************************************************************/

#include "lzo/lzoconf.h"
#include "lzo/lzo1x.h"

/* portability layer */
#define WANT_LZO_MALLOC 1
#define WANT_LZO_FREAD 1
#define WANT_LZO_WILDARGV 1
#include "examples/portab.h"


static const char *progname = NULL;

#define DICT_LEN    0xbfff
static lzo_bytep    dict;
static lzo_uint     dict_len = 0;
static lzo_uint32   dict_adler32;


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

static lzo_uint total_n = 0;
static lzo_uint total_c_len = 0;
static lzo_uint total_d_len = 0;

static void print_file ( const char *name, lzo_uint d_len, lzo_uint c_len )
{
    double perc;

    perc = (d_len > 0) ? c_len * 100.0 / d_len : 0;
    printf("  |  %-30s   %9ld -> %9ld   %7.2f%%  |\n",
            name, (long) d_len, (long) c_len, perc);

    total_n++;
    total_c_len += c_len;
    total_d_len += d_len;
}


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

int do_file ( const char *in_name, int level )
{
    int r;
    lzo_bytep in;
    lzo_bytep out;
    lzo_bytep newb;
    lzo_bytep wrkmem;
    lzo_uint in_len;
    lzo_uint out_len;
    lzo_uint new_len;
    long l;
    FILE *f;

/*
 * Step 1: open the input file
 */
    f = fopen(in_name,"rb");
    if (f == 0)
    {
        printf("%s: cannot open file %s\n", progname, in_name);
        return 0;   /* no error */
    }
    fseek(f,0,SEEK_END);
    l = ftell(f);
    fseek(f,0,SEEK_SET);
    if (l <= 0)
    {
        printf("%s: %s: empty file -- skipping\n", progname, in_name);
        fclose(f);
        return 0;
    }
    in_len = (lzo_uint) l;

/*
 * Step 2: allocate compression buffers and read the file
 */
    in = (lzo_bytep) lzo_malloc(in_len);
    out = (lzo_bytep) lzo_malloc(in_len + in_len / 16 + 64 + 3);
    newb = (lzo_bytep) lzo_malloc(in_len);
    wrkmem = (lzo_bytep) lzo_malloc(LZO1X_999_MEM_COMPRESS);
    if (in == NULL || out == NULL || newb == NULL || wrkmem == NULL)
    {
        printf("%s: out of memory\n", progname);
        exit(1);
    }
    in_len = (lzo_uint) lzo_fread(f,in,in_len);
    fclose(f);

/*
 * Step 3: compress from `in' to `out' with LZO1X-999
 */
    r = lzo1x_999_compress_level(in,in_len,out,&out_len,wrkmem,
                                 dict, dict_len, 0, level);
    if (r != LZO_E_OK)
    {
        /* this should NEVER happen */
        printf("internal error - compression failed: %d\n", r);
        return 1;
    }

    print_file(in_name,in_len,out_len);

/*
 * Step 4: decompress again, now going from `out' to `newb'
 */
    new_len = in_len;
    r = lzo1x_decompress_dict_safe(out,out_len,newb,&new_len,NULL,dict,dict_len);
    if (r != LZO_E_OK)
    {
        /* this should NEVER happen */
        printf("internal error - decompression failed: %d\n", r);
        return 1;
    }

/*
 * Step 5: verify decompression
 */
    if (new_len != in_len || lzo_memcmp(in,newb,in_len) != 0)
    {
        /* this should NEVER happen */
        printf("internal error - decompression data error\n");
        return 1;
    }

    /* free buffers in reverse order to help malloc() */
    lzo_free(wrkmem);
    lzo_free(newb);
    lzo_free(out);
    lzo_free(in);
    return 0;
}


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

int __lzo_cdecl_main main(int argc, char *argv[])
{
    int i = 1;
    int r;
    const char *dict_name;
    FILE *f;
    time_t t_total;
    int level = 7;

    lzo_wildargv(&argc, &argv);

    printf("\nLZO real-time data compression library (v%s, %s).\n",
           lzo_version_string(), lzo_version_date());
    printf("Copyright (C) 1996-2008 Markus Franz Xaver Johannes Oberhumer\nAll Rights Reserved.\n\n");

    progname = argv[0];

    if (i < argc && argv[i][0] == '-' && isdigit(argv[i][1]))
        level = atoi(&argv[i++][1]);

    if (i + 1 >= argc || level < 1 || level > 9)
    {
        printf("usage: %s [-level] [ dictionary-file | -n ]  file...\n", progname);
        exit(1);
    }
    printf("Compression level is LZO1X-999/%d\n", level);

/*
 * 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");
        exit(1);
    }

/*
 * Step 2: prepare the dictionary
 */
    dict = (lzo_bytep) lzo_malloc(DICT_LEN);
    if (dict == NULL)
    {
        printf("%s: out of memory\n", progname);
        exit(1);
    }
    dict_name = argv[i++];
    if (strcmp(dict_name,"-n") == 0)
    {
        dict_name = "empty";
        dict_len = 0;
    }
    else
    {
        f = fopen(dict_name,"rb");
        if (!f)
        {
            printf("%s: cannot open dictionary file %s\n", progname, dict_name);
            exit(1);
        }
        dict_len = (lzo_uint) lzo_fread(f,dict,DICT_LEN);
        fclose(f);
    }

    dict_adler32 = lzo_adler32(0,NULL,0);
    dict_adler32 = lzo_adler32(dict_adler32,dict,dict_len);
    printf("Using dictionary '%s', %ld bytes, ID 0x%08lx.\n",
            dict_name, (long) dict_len, (long) dict_adler32);

/*
 * Step 3: process files
 */
    t_total = time(NULL);
    for (r = 0; r == 0 && i < argc; i++)
        r = do_file(argv[i], level);
    t_total = time(NULL) - t_total;

    lzo_free(dict);

    if (total_n > 1)
        print_file("***TOTALS***",total_d_len,total_c_len);

    printf("Dictionary compression test %s, execution time %lu seconds.\n",
            r == 0 ? "passed" : "FAILED", (unsigned long) t_total);
    return r;
}

/*
vi:ts=4:et
*/