1 /* ----------------------------------------------------------------------- *
3 * Copyright 2009 Intel Corporation; author: H. Peter Anvin
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
8 * Boston MA 02110-1301, USA; either version 2 of the License, or
9 * (at your option) any later version; incorporated herein by reference.
11 * ----------------------------------------------------------------------- */
14 This file is based in part on:
16 precomp2.c -- example program: how to generate pre-compressed data
18 This file is part of the LZO real-time data compression library.
20 Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
21 Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
22 Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
23 Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
24 Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
25 Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
26 Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
27 Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
28 Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
29 Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
30 Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
31 Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
32 Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
35 The LZO library is free software; you can redistribute it and/or
36 modify it under the terms of the GNU General Public License as
37 published by the Free Software Foundation; either version 2 of
38 the License, or (at your option) any later version.
40 The LZO library is distributed in the hope that it will be useful,
41 but WITHOUT ANY WARRANTY; without even the implied warranty of
42 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
43 GNU General Public License for more details.
45 You should have received a copy of the GNU General Public License
46 along with the LZO library; see the file COPYING.
47 If not, write to the Free Software Foundation, Inc.,
48 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
50 Markus F.X.J. Oberhumer
51 <markus@oberhumer.com>
52 http://www.oberhumer.com/opensource/lzo/
55 #include "lzo/lzoconf.h"
56 #include "lzo/lzo1x.h"
59 lzo1x_999_compress_internal(const lzo_bytep in, lzo_uint in_len,
60 lzo_bytep out, lzo_uintp out_len,
62 const lzo_bytep dict, lzo_uint dict_len,
68 lzo_uint max_chain, lzo_uint32 flags);
71 lzo1y_999_compress_internal(const lzo_bytep in, lzo_uint in_len,
72 lzo_bytep out, lzo_uintp out_len,
74 const lzo_bytep dict, lzo_uint dict_len,
80 lzo_uint max_chain, lzo_uint32 flags);
95 uint32_t pfx_compressed;
96 uint32_t pfx_cdatalen;
97 uint32_t pfx_checksum;
100 static inline uint32_t get_32(const uint32_t * p)
102 #if defined(__i386__) || defined(__x86_64__)
103 /* Littleendian and unaligned-capable */
106 const uint8_t *pp = (const uint8_t *)p;
107 return (uint32_t) pp[0] + ((uint32_t) pp[1] << 8) +
108 ((uint32_t) pp[2] << 16) + ((uint32_t) pp[3] << 24);
112 static inline void set_32(uint32_t * p, uint32_t v)
114 #if defined(__i386__) || defined(__x86_64__)
115 /* Littleendian and unaligned-capable */
118 uint8_t *pp = (uint8_t *) p;
120 pp[1] = ((v >> 8) & 0xff);
121 pp[2] = ((v >> 16) & 0xff);
122 pp[3] = ((v >> 24) & 0xff);
126 /*************************************************************************
128 **************************************************************************/
130 int __lzo_cdecl_main main(int argc, char *argv[])
134 const int max_try_lazy = 5;
135 const lzo_uint big = 65536L; /* can result in very slow compression */
136 const lzo_uint32 flags = 0x1;
140 lzo_uint in_len, infile_len, start, offset, soff;
143 lzo_uint out_bufsize;
144 lzo_uint out_len = 0;
145 lzo_uint outfile_len;
147 lzo_byte wrkmem[LZO1X_999_MEM_COMPRESS];
153 lzo_uint32 uncompressed_checksum;
154 lzo_uint32 compressed_checksum;
157 const char *progname = NULL;
158 const char *in_name = NULL;
159 const char *out_name = NULL;
162 struct prefix *prefix;
166 printf("usage: %s file output-file\n", progname);
174 * Step 1: initialize the LZO library
176 if (lzo_init() != LZO_E_OK) {
177 printf("internal error - lzo_init() failed !!!\n");
179 ("(this usually indicates a compiler bug - try recompiling\nwithout optimizations, and enable `-DLZO_DEBUG' for diagnostics)\n");
184 * Step 3: open the input file
186 f = fopen(in_name, "rb");
188 printf("%s: cannot open file %s\n", progname, in_name);
191 fseek(f, 0, SEEK_END);
193 fseek(f, 0, SEEK_SET);
195 printf("%s: %s: empty file\n", progname, in_name);
199 infile_len = (lzo_uint) l;
200 out_bufsize = infile_len + infile_len / 16 + 64 + 3 + 2048;
203 * Step 4: allocate compression buffers and read the file
205 infile = (lzo_bytep) malloc(infile_len);
206 out = (lzo_bytep) malloc(out_bufsize);
207 if (infile == NULL || out == NULL) {
208 printf("%s: out of memory\n", progname);
211 infile_len = (lzo_uint) fread(infile, 1, infile_len, f);
215 * Select the portion which is for compression...
217 prefix = (struct prefix *)infile;
218 start = get_32(&prefix->pfx_start);
219 offset = get_32(&prefix->pfx_compressed);
220 in = infile + offset;
221 in_len = infile_len - offset;
225 * Step 5: compute a checksum of the uncompressed data
227 uncompressed_checksum = lzo_adler32(0, NULL, 0);
228 uncompressed_checksum = lzo_adler32(uncompressed_checksum, in, in_len);
231 * Step 6a: compress from `in' to `out' with LZO1X-999
233 for (lazy = 0; lazy <= max_try_lazy; lazy++) {
234 out_len = out_bufsize;
235 r = lzo1x_999_compress_internal(in, in_len, out, &out_len, wrkmem,
237 lazy, big, big, big, big, flags);
239 /* this should NEVER happen */
240 printf("internal error - compression failed: %d\n", r);
243 if (out_len < best_len) {
250 * Step 7: check if compressible
252 if (best_len >= in_len) {
253 printf("This file contains incompressible data.\n");
254 /* return 0; -- Sucks to be us -hpa ... */
258 * Step 8: compress data again using the best compressor found
260 out_len = out_bufsize;
261 r = lzo1x_999_compress_internal(in, in_len, out, &out_len, wrkmem,
263 best_lazy, big, big, big, big, flags);
264 assert(r == LZO_E_OK);
265 assert(out_len == best_len);
268 * Step 9: optimize compressed data (compressed data is in `out' buffer)
271 /* Optimization does not require any data in the buffer that will
272 * hold the uncompressed data. To prove this, we clear the buffer.
274 memset(in, 0, in_len);
278 r = lzo1x_optimize(out, out_len, in, &orig_len, NULL);
279 if (r != LZO_E_OK || orig_len != in_len) {
280 /* this should NEVER happen */
281 printf("internal error - optimization failed: %d\n", r);
286 * Step 10: compute a checksum of the compressed data
288 compressed_checksum = lzo_adler32(0, NULL, 0);
289 compressed_checksum = lzo_adler32(compressed_checksum, out, out_len);
292 * Step 11: write compressed data to a file
294 /* Make sure we have up to 2048 bytes of zero after the output */
295 memset(out + out_len, 0, 2048);
297 outfile_len = out_len;
299 soff = get_32(&prefix->pfx_cdatalen);
300 set_32((uint32_t *) (infile + soff), out_len);
302 soff = get_32(&prefix->pfx_checksum);
304 /* ISOLINUX padding and checksumming */
308 ((offset - start + out_len + 2047) & ~2047) - (offset - start);
309 for (ptr = 64; ptr < offset; ptr += 4)
310 csum += get_32((uint32_t *) (infile + ptr));
311 for (ptr = 0; ptr < outfile_len; ptr += 4)
312 csum += get_32((uint32_t *) (out + ptr));
314 set_32((uint32_t *) (infile + soff), offset - start + outfile_len);
315 set_32((uint32_t *) (infile + soff + 4), csum);
318 f = fopen(out_name, "wb");
320 printf("%s: cannot open output file %s\n", progname, out_name);
323 if (fwrite(infile + start, 1, offset - start, f) != offset - start ||
324 fwrite(out, 1, outfile_len, f) != outfile_len || fclose(f)) {
325 printf("%s: write error !!\n", progname);
330 * Step 12: verify decompression
333 memset(in, 0, in_len); /* paranoia - clear output buffer */
335 r = lzo1x_decompress_safe(out, out_len, in, &orig_len, NULL);
336 if (r != LZO_E_OK || orig_len != in_len) {
337 /* this should NEVER happen */
338 printf("internal error - decompression failed: %d\n", r);
341 if (uncompressed_checksum !=
342 lzo_adler32(lzo_adler32(0, NULL, 0), in, in_len)) {
343 /* this should NEVER happen */
344 printf("internal error - decompression data error\n");
347 /* Now you could also verify decompression under similar conditions as in
348 * your application, e.g. overlapping assembler decompression etc.