liblzf/lzf.c

/*
 * Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de>
 * 
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, 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.
 * 
 *   3.  The name of the author may not be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
 * CIAL, 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 OTH-
 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License version 2 (the "GPL"), in which case the
 * provisions of the GPL are applicable instead of the above. If you wish to
 * allow the use of your version of this file only under the terms of the
 * GPL and not to allow others to use your version of this file under the
 * BSD license, indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by the GPL. If
 * you do not delete the provisions above, a recipient may use your version
 * of this file under either the BSD or the GPL.
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#include <unistd.h>
#include <getopt.h>

#include "lzf.h"

typedef unsigned char u8;

static void
usage (int ec)
{
  fprintf (stderr, "\n"
           "lzf, a very lightweight compression/decompression filter\n"
           "written by Marc Lehmann <schmorp@schmorp.de> You can find more info at\n"
           "http://liblzf.plan9.de/\n"
           "\n"
           "USAGE: lzf -c [-b blocksize] | -d\n"
           "          -c  compress\n"
           "          -d  decompress\n"
           "          -b  specify the blocksize (default 64k-1)\n"
           "\n"
    );

  exit (ec);
}

/*
 * Anatomy: an lzf file consists of any number of blocks in the following format:
 *
 * \x00   EOF (optional)
 * "ZV\0" 2-byte-usize <uncompressed data>
 * "ZV\1" 2-byte-csize 2-byte-usize <compressed data>
 * "ZV\2" 4-byte-crc32-0xdebb20e3 (NYI)
 * 
 */

static void compress (unsigned int blocksize)
{
  ssize_t us;
  unsigned int cs;
  u8 buff1[64*1024];
  u8 buff2[64*1024];
  u8 header[3+2+2];

  header[0] = 'Z';
  header[1] = 'V';

  for(;;) {
    us = fread (buff1, 1, blocksize, stdin);

    if (us < blocksize)
      {
        if (us == 0)
          break;
        else if (!feof (stdin))
          {
            perror ("compress");
            exit (1);
          }
      }

    cs = lzf_compress (buff1, us, buff2, us - 4);

    if (cs)
      {
        header[2] = 1;
        header[3] = cs >> 8;
        header[4] = cs & 0xff;
        header[5] = us >> 8;
        header[6] = us & 0xff;

        fwrite (header, 3+2+2, 1, stdout);
        fwrite (buff2, cs, 1, stdout);
      }
    else
      {
        header[2] = 0;
        header[3] = us >> 8;
        header[4] = us & 0xff;

        fwrite (header, 3+2, 1, stdout);
        fwrite (buff1, us, 1, stdout);
      }
  }
}

static void decompress (void)
{
  ssize_t us;
  unsigned int cs;
  u8 buff1[64*1024];
  u8 buff2[64*1024];
  u8 header[3+2+2];

  for(;;) {
    int hdrsize = fread (header, 1, 3+2, stdin);

    /* check for \0 record */
    if (hdrsize)
      {
        if (!header[0])
          break;
        else if (hdrsize != 3+2)
          {
            if (feof (stdin))
              fprintf (stderr, "decompress: invalid stream - short header\n");
            else
              perror ("decompress");

            exit (1);
          }
      }
    else
      {
        if (feof (stdin))
          break;
        else
          {
            perror ("decompress");
            exit (1);
          }
      }

    if (header[0] != 'Z' || header[1] != 'V')
      {
        fprintf (stderr, "decompress: invalid stream - no magic number found\n");
        exit (1);
      }

    cs = (header[3] << 8) | header[4];

    if (header[2] == 1)
      {
        if (fread (header+3+2, 2, 1, stdin) != 1)
          {
            perror ("decompress");
            exit (1);
          }

        us = (header[5] << 8) | header[6];

        if (fread (buff1, cs, 1, stdin) != 1)
          {
            perror ("decompress");
            exit (1);
          }

        if (lzf_decompress (buff1, cs, buff2, us) != us)
          {
            fprintf (stderr, "decompress: invalid stream - data corrupted\n");
            exit (1);
          }

        fwrite (buff2, us, 1, stdout);
      }
    else if (header[2] == 0)
      {
        if (fread (buff2, cs, 1, stdin) != 1)
          {
            perror ("decompress");
            exit (1);
          }

        fwrite (buff2, cs, 1, stdout);
      }
    else
      {
        fprintf (stderr, "decompress: invalid stream - unknown block type\n");
        exit (1);
      }
  }
}

int
main (int argc, char *argv[])
{
  int c;
  unsigned int blocksize = 64*1024-1;
  enum { m_compress, m_decompress } mode = m_compress;

  while ((c = getopt (argc, argv, "cdb:h")) != -1)
    switch (c)
      {
      case 'c':
        mode = m_compress;
        break;

      case 'd':
        mode = m_decompress;
        break;

      case 'b':
        blocksize = atol (optarg);
        break;

      case 'h':
        usage (0);

      case ':':
        fprintf (stderr, "required argument missing, use -h\n");
        exit (1);

      case '?':
        fprintf (stderr, "unknown option, use -h\n");
        exit (1);

      default:
        usage (1);
      }

  if (mode == m_compress)
    compress (blocksize);
  else if (mode == m_decompress)
    decompress ();
  else
    abort ();

  return 0;
}
Revision:	1.9
Committed:	Fri Sep 29 19:43:01 2006 UTC (17 years, 7 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.8:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	/*
2	root	1.5	* Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de>
3	root	1.1	*
4			* Redistribution and use in source and binary forms, with or without modifica-
5			* tion, are permitted provided that the following conditions are met:
6			*
7			* 1. Redistributions of source code must retain the above copyright notice,
8			* this list of conditions and the following disclaimer.
9			*
10			* 2. Redistributions in binary form must reproduce the above copyright
11			* notice, this list of conditions and the following disclaimer in the
12			* documentation and/or other materials provided with the distribution.
13			*
14			* 3. The name of the author may not be used to endorse or promote products
15			* derived from this software without specific prior written permission.
16			*
17			* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18			* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19			* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20			* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21			* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22			* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23			* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24			* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25			* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26			* OF THE POSSIBILITY OF SUCH DAMAGE.
27	pcg	1.4	*
28			* Alternatively, the contents of this file may be used under the terms of
29			* the GNU General Public License version 2 (the "GPL"), in which case the
30			* provisions of the GPL are applicable instead of the above. If you wish to
31			* allow the use of your version of this file only under the terms of the
32			* GPL and not to allow others to use your version of this file under the
33			* BSD license, indicate your decision by deleting the provisions above and
34			* replace them with the notice and other provisions required by the GPL. If
35			* you do not delete the provisions above, a recipient may use your version
36			* of this file under either the BSD or the GPL.
37	root	1.1	*/
38
39			#include "config.h"
40
41			#include <stdio.h>
42			#include <stdlib.h>
43	root	1.6	#include <string.h>
44	root	1.1	#include <assert.h>
45
46			#include <unistd.h>
47			#include <getopt.h>
48
49			#include "lzf.h"
50
51	pcg	1.3	typedef unsigned char u8;
52
53	root	1.1	static void
54			usage (int ec)
55			{
56			fprintf (stderr, "\n"
57	pcg	1.3	"lzf, a very lightweight compression/decompression filter\n"
58	root	1.5	"written by Marc Lehmann <schmorp@schmorp.de> You can find more info at\n"
59	pcg	1.3	"http://liblzf.plan9.de/\n"
60	root	1.1	"\n"
61			"USAGE: lzf -c [-b blocksize] \| -d\n"
62			" -c compress\n"
63			" -d decompress\n"
64			" -b specify the blocksize (default 64k-1)\n"
65			"\n"
66			);
67
68			exit (ec);
69			}
70
71			/*
72			* Anatomy: an lzf file consists of any number of blocks in the following format:
73			*
74	root	1.8	* \x00 EOF (optional)
75	root	1.1	* "ZV\0" 2-byte-usize <uncompressed data>
76			* "ZV\1" 2-byte-csize 2-byte-usize <compressed data>
77			* "ZV\2" 4-byte-crc32-0xdebb20e3 (NYI)
78			*
79			*/
80
81			static void compress (unsigned int blocksize)
82			{
83			ssize_t us;
84			unsigned int cs;
85			u8 buff1[64*1024];
86			u8 buff2[64*1024];
87			u8 header[3+2+2];
88
89			header[0] = 'Z';
90			header[1] = 'V';
91
92			for(;;) {
93			us = fread (buff1, 1, blocksize, stdin);
94
95			if (us < blocksize)
96			{
97			if (us == 0)
98			break;
99			else if (!feof (stdin))
100			{
101			perror ("compress");
102			exit (1);
103			}
104			}
105
106			cs = lzf_compress (buff1, us, buff2, us - 4);
107
108			if (cs)
109			{
110			header[2] = 1;
111			header[3] = cs >> 8;
112			header[4] = cs & 0xff;
113			header[5] = us >> 8;
114			header[6] = us & 0xff;
115
116			fwrite (header, 3+2+2, 1, stdout);
117			fwrite (buff2, cs, 1, stdout);
118			}
119			else
120			{
121			header[2] = 0;
122			header[3] = us >> 8;
123			header[4] = us & 0xff;
124
125			fwrite (header, 3+2, 1, stdout);
126			fwrite (buff1, us, 1, stdout);
127			}
128	root	1.9	}
129	root	1.1	}
130
131			static void decompress (void)
132			{
133			ssize_t us;
134			unsigned int cs;
135			u8 buff1[64*1024];
136			u8 buff2[64*1024];
137			u8 header[3+2+2];
138
139			for(;;) {
140	root	1.8	int hdrsize = fread (header, 1, 3+2, stdin);
141
142			/* check for \0 record */
143			if (hdrsize)
144			{
145			if (!header[0])
146			break;
147			else if (hdrsize != 3+2)
148			{
149			if (feof (stdin))
150			fprintf (stderr, "decompress: invalid stream - short header\n");
151			else
152			perror ("decompress");
153
154			exit (1);
155			}
156			}
157			else
158	root	1.1	{
159			if (feof (stdin))
160			break;
161			else
162			{
163			perror ("decompress");
164			exit (1);
165			}
166			}
167
168			if (header[0] != 'Z' \|\| header[1] != 'V')
169			{
170			fprintf (stderr, "decompress: invalid stream - no magic number found\n");
171			exit (1);
172			}
173
174			cs = (header[3] << 8) \| header[4];
175
176			if (header[2] == 1)
177			{
178			if (fread (header+3+2, 2, 1, stdin) != 1)
179			{
180			perror ("decompress");
181			exit (1);
182			}
183
184			us = (header[5] << 8) \| header[6];
185
186			if (fread (buff1, cs, 1, stdin) != 1)
187			{
188			perror ("decompress");
189			exit (1);
190			}
191
192			if (lzf_decompress (buff1, cs, buff2, us) != us)
193			{
194			fprintf (stderr, "decompress: invalid stream - data corrupted\n");
195			exit (1);
196			}
197
198			fwrite (buff2, us, 1, stdout);
199			}
200			else if (header[2] == 0)
201			{
202			if (fread (buff2, cs, 1, stdin) != 1)
203			{
204			perror ("decompress");
205			exit (1);
206			}
207
208			fwrite (buff2, cs, 1, stdout);
209			}
210			else
211			{
212			fprintf (stderr, "decompress: invalid stream - unknown block type\n");
213			exit (1);
214			}
215			}
216			}
217
218			int
219			main (int argc, char *argv[])
220			{
221			int c;
222			unsigned int blocksize = 64*1024-1;
223			enum { m_compress, m_decompress } mode = m_compress;
224
225			while ((c = getopt (argc, argv, "cdb:h")) != -1)
226			switch (c)
227			{
228			case 'c':
229			mode = m_compress;
230			break;
231
232			case 'd':
233			mode = m_decompress;
234			break;
235
236			case 'b':
237			blocksize = atol (optarg);
238			break;
239
240			case 'h':
241			usage (0);
242
243			case ':':
244			fprintf (stderr, "required argument missing, use -h\n");
245			exit (1);
246
247			case '?':
248			fprintf (stderr, "unknown option, use -h\n");
249			exit (1);
250
251			default:
252			usage (1);
253			}
254
255			if (mode == m_compress)
256			compress (blocksize);
257			else if (mode == m_decompress)
258			decompress ();
259			else
260			abort ();
261
262			return 0;
263			}