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Revision: 1.6
Committed: Fri Jul 7 15:34:11 2006 UTC (18 years, 3 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: rel-1_6
Changes since 1.5: +4 -0 lines
Log Message:
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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 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     * "ZV\0" 2-byte-usize <uncompressed data>
75     * "ZV\1" 2-byte-csize 2-byte-usize <compressed data>
76     * "ZV\2" 4-byte-crc32-0xdebb20e3 (NYI)
77     *
78     */
79    
80     static void compress (unsigned int blocksize)
81     {
82     ssize_t us;
83     unsigned int cs;
84     u8 buff1[64*1024];
85     u8 buff2[64*1024];
86     u8 header[3+2+2];
87    
88     header[0] = 'Z';
89     header[1] = 'V';
90    
91     for(;;) {
92     us = fread (buff1, 1, blocksize, stdin);
93    
94     if (us < blocksize)
95     {
96     if (us == 0)
97     break;
98     else if (!feof (stdin))
99     {
100     perror ("compress");
101     exit (1);
102     }
103     }
104    
105     cs = lzf_compress (buff1, us, buff2, us - 4);
106    
107     if (cs)
108     {
109     header[2] = 1;
110     header[3] = cs >> 8;
111     header[4] = cs & 0xff;
112     header[5] = us >> 8;
113     header[6] = us & 0xff;
114    
115     fwrite (header, 3+2+2, 1, stdout);
116     fwrite (buff2, cs, 1, stdout);
117     }
118     else
119     {
120     header[2] = 0;
121     header[3] = us >> 8;
122     header[4] = us & 0xff;
123    
124     fwrite (header, 3+2, 1, stdout);
125     fwrite (buff1, us, 1, stdout);
126     }
127     } while (!feof (stdin));
128     }
129    
130     static void decompress (void)
131     {
132     ssize_t us;
133     unsigned int cs;
134     u8 buff1[64*1024];
135     u8 buff2[64*1024];
136     u8 header[3+2+2];
137    
138     for(;;) {
139     if (fread (header, 3+2, 1, stdin) != 1)
140     {
141     if (feof (stdin))
142     break;
143     else
144     {
145     perror ("decompress");
146     exit (1);
147     }
148     }
149    
150     if (header[0] != 'Z' || header[1] != 'V')
151     {
152     fprintf (stderr, "decompress: invalid stream - no magic number found\n");
153     exit (1);
154     }
155    
156     cs = (header[3] << 8) | header[4];
157    
158     if (header[2] == 1)
159     {
160     if (fread (header+3+2, 2, 1, stdin) != 1)
161     {
162     perror ("decompress");
163     exit (1);
164     }
165    
166     us = (header[5] << 8) | header[6];
167    
168     if (fread (buff1, cs, 1, stdin) != 1)
169     {
170     perror ("decompress");
171     exit (1);
172     }
173    
174     if (lzf_decompress (buff1, cs, buff2, us) != us)
175     {
176     fprintf (stderr, "decompress: invalid stream - data corrupted\n");
177     exit (1);
178     }
179    
180     fwrite (buff2, us, 1, stdout);
181     }
182     else if (header[2] == 0)
183     {
184     if (fread (buff2, cs, 1, stdin) != 1)
185     {
186     perror ("decompress");
187     exit (1);
188     }
189    
190     fwrite (buff2, cs, 1, stdout);
191     }
192     else
193     {
194     fprintf (stderr, "decompress: invalid stream - unknown block type\n");
195     exit (1);
196     }
197     }
198     }
199    
200     int
201     main (int argc, char *argv[])
202     {
203     int c;
204     unsigned int blocksize = 64*1024-1;
205     enum { m_compress, m_decompress } mode = m_compress;
206    
207 root 1.6 if (!strcmp (argv[0] + strlen (argv[0] - 5), "unlzf"))
208     mode = m_decompress;
209    
210 root 1.1 while ((c = getopt (argc, argv, "cdb:h")) != -1)
211     switch (c)
212     {
213     case 'c':
214     mode = m_compress;
215     break;
216    
217     case 'd':
218     mode = m_decompress;
219     break;
220    
221     case 'b':
222     blocksize = atol (optarg);
223     break;
224    
225     case 'h':
226     usage (0);
227    
228     case ':':
229     fprintf (stderr, "required argument missing, use -h\n");
230     exit (1);
231    
232     case '?':
233     fprintf (stderr, "unknown option, use -h\n");
234     exit (1);
235    
236     default:
237     usage (1);
238     }
239    
240     if (mode == m_compress)
241     compress (blocksize);
242     else if (mode == m_decompress)
243     decompress ();
244     else
245     abort ();
246    
247     return 0;
248     }