liblzf/lzf.c

/*
 * Copyright (c) 2000-2003 Marc Alexander Lehmann <pcg@goof.com>
 * 
 * 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 <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 <pcg@goof.com> 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:
 *
 * "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);
      }
  } while (!feof (stdin));
}

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

  for(;;) {
    if (fread (header, 3+2, 1, stdin) != 1)
      {
        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:	1.4
Committed:	Tue Apr 20 18:11:57 2004 UTC (20 years, 1 month ago) by pcg
Content type:	text/plain
Branch:	MAIN
Changes since 1.3:	+10 -0 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* Copyright (c) 2000-2003 Marc Alexander Lehmann <pcg@goof.com>
3	*
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	*
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	*/
38
39	#include "config.h"
40
41	#include <stdio.h>
42	#include <stdlib.h>
43	#include <assert.h>
44
45	#include <unistd.h>
46	#include <getopt.h>
47
48	#include "lzf.h"
49
50	typedef unsigned char u8;
51
52	static void
53	usage (int ec)
54	{
55	fprintf (stderr, "\n"
56	"lzf, a very lightweight compression/decompression filter\n"
57	"written by Marc Lehmann <pcg@goof.com> You can find more info at\n"
58	"http://liblzf.plan9.de/\n"
59	"\n"
60	"USAGE: lzf -c [-b blocksize] \| -d\n"
61	" -c compress\n"
62	" -d decompress\n"
63	" -b specify the blocksize (default 64k-1)\n"
64	"\n"
65	);
66
67	exit (ec);
68	}
69
70	/*
71	* Anatomy: an lzf file consists of any number of blocks in the following format:
72	*
73	* "ZV\0" 2-byte-usize <uncompressed data>
74	* "ZV\1" 2-byte-csize 2-byte-usize <compressed data>
75	* "ZV\2" 4-byte-crc32-0xdebb20e3 (NYI)
76	*
77	*/
78
79	static void compress (unsigned int blocksize)
80	{
81	ssize_t us;
82	unsigned int cs;
83	u8 buff1[64*1024];
84	u8 buff2[64*1024];
85	u8 header[3+2+2];
86
87	header[0] = 'Z';
88	header[1] = 'V';
89
90	for(;;) {
91	us = fread (buff1, 1, blocksize, stdin);
92
93	if (us < blocksize)
94	{
95	if (us == 0)
96	break;
97	else if (!feof (stdin))
98	{
99	perror ("compress");
100	exit (1);
101	}
102	}
103
104	cs = lzf_compress (buff1, us, buff2, us - 4);
105
106	if (cs)
107	{
108	header[2] = 1;
109	header[3] = cs >> 8;
110	header[4] = cs & 0xff;
111	header[5] = us >> 8;
112	header[6] = us & 0xff;
113
114	fwrite (header, 3+2+2, 1, stdout);
115	fwrite (buff2, cs, 1, stdout);
116	}
117	else
118	{
119	header[2] = 0;
120	header[3] = us >> 8;
121	header[4] = us & 0xff;
122
123	fwrite (header, 3+2, 1, stdout);
124	fwrite (buff1, us, 1, stdout);
125	}
126	} while (!feof (stdin));
127	}
128
129	static void decompress (void)
130	{
131	ssize_t us;
132	unsigned int cs;
133	u8 buff1[64*1024];
134	u8 buff2[64*1024];
135	u8 header[3+2+2];
136
137	for(;;) {
138	if (fread (header, 3+2, 1, stdin) != 1)
139	{
140	if (feof (stdin))
141	break;
142	else
143	{
144	perror ("decompress");
145	exit (1);
146	}
147	}
148
149	if (header[0] != 'Z' \|\| header[1] != 'V')
150	{
151	fprintf (stderr, "decompress: invalid stream - no magic number found\n");
152	exit (1);
153	}
154
155	cs = (header[3] << 8) \| header[4];
156
157	if (header[2] == 1)
158	{
159	if (fread (header+3+2, 2, 1, stdin) != 1)
160	{
161	perror ("decompress");
162	exit (1);
163	}
164
165	us = (header[5] << 8) \| header[6];
166
167	if (fread (buff1, cs, 1, stdin) != 1)
168	{
169	perror ("decompress");
170	exit (1);
171	}
172
173	if (lzf_decompress (buff1, cs, buff2, us) != us)
174	{
175	fprintf (stderr, "decompress: invalid stream - data corrupted\n");
176	exit (1);
177	}
178
179	fwrite (buff2, us, 1, stdout);
180	}
181	else if (header[2] == 0)
182	{
183	if (fread (buff2, cs, 1, stdin) != 1)
184	{
185	perror ("decompress");
186	exit (1);
187	}
188
189	fwrite (buff2, cs, 1, stdout);
190	}
191	else
192	{
193	fprintf (stderr, "decompress: invalid stream - unknown block type\n");
194	exit (1);
195	}
196	}
197	}
198
199	int
200	main (int argc, char *argv[])
201	{
202	int c;
203	unsigned int blocksize = 64*1024-1;
204	enum { m_compress, m_decompress } mode = m_compress;
205
206	while ((c = getopt (argc, argv, "cdb:h")) != -1)
207	switch (c)
208	{
209	case 'c':
210	mode = m_compress;
211	break;
212
213	case 'd':
214	mode = m_decompress;
215	break;
216
217	case 'b':
218	blocksize = atol (optarg);
219	break;
220
221	case 'h':
222	usage (0);
223
224	case ':':
225	fprintf (stderr, "required argument missing, use -h\n");
226	exit (1);
227
228	case '?':
229	fprintf (stderr, "unknown option, use -h\n");
230	exit (1);
231
232	default:
233	usage (1);
234	}
235
236	if (mode == m_compress)
237	compress (blocksize);
238	else if (mode == m_decompress)
239	decompress ();
240	else
241	abort ();
242
243	return 0;
244	}