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Revision: 1.5
Committed: Thu Mar 3 17:06:44 2005 UTC (19 years, 7 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: rel-1_5, rel-1_51
Changes since 1.4: +2 -2 lines
Log Message:
*** empty log message ***

File Contents

# 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     #include <assert.h>
44    
45     #include <unistd.h>
46     #include <getopt.h>
47    
48     #include "lzf.h"
49    
50 pcg 1.3 typedef unsigned char u8;
51    
52 root 1.1 static void
53     usage (int ec)
54     {
55     fprintf (stderr, "\n"
56 pcg 1.3 "lzf, a very lightweight compression/decompression filter\n"
57 root 1.5 "written by Marc Lehmann <schmorp@schmorp.de> You can find more info at\n"
58 pcg 1.3 "http://liblzf.plan9.de/\n"
59 root 1.1 "\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     }