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;
149 lzo_byte wrkmem[LZO1X_999_MEM_COMPRESS];
155 lzo_uint32 uncompressed_checksum;
156 lzo_uint32 compressed_checksum;
159 const char *progname = NULL;
160 const char *in_name = NULL;
161 const char *out_name = NULL;
164 struct prefix *prefix;
168 printf("usage: %s file output-file\n", progname);
176 * Step 1: initialize the LZO library
178 if (lzo_init() != LZO_E_OK) {
179 printf("internal error - lzo_init() failed !!!\n");
181 ("(this usually indicates a compiler bug - try recompiling\nwithout optimizations, and enable `-DLZO_DEBUG' for diagnostics)\n");
186 * Step 3: open the input file
188 f = fopen(in_name, "rb");
190 printf("%s: cannot open file %s\n", progname, in_name);
193 fseek(f, 0, SEEK_END);
195 fseek(f, 0, SEEK_SET);
197 printf("%s: %s: empty file\n", progname, in_name);
201 infile_len = (lzo_uint) l;
202 out_bufsize = infile_len + infile_len / 16 + 64 + 3 + 2048;
205 * Step 4: allocate compression buffers and read the file
207 infile = (lzo_bytep) malloc(infile_len);
208 out = (lzo_bytep) malloc(out_bufsize);
209 if (infile == NULL || out == NULL) {
210 printf("%s: out of memory\n", progname);
213 infile_len = (lzo_uint) fread(infile, 1, infile_len, f);
217 * Select the portion which is for compression...
219 prefix = (struct prefix *)infile;
220 start = get_32(&prefix->pfx_start);
221 offset = get_32(&prefix->pfx_compressed);
222 in = infile + offset;
223 in_len = infile_len - offset;
227 * Step 5: compute a checksum of the uncompressed data
229 uncompressed_checksum = lzo_adler32(0, NULL, 0);
230 uncompressed_checksum = lzo_adler32(uncompressed_checksum, in, in_len);
233 * Step 6a: compress from `in' to `out' with LZO1X-999
235 for (lazy = 0; lazy <= max_try_lazy; lazy++) {
236 out_len = out_bufsize;
237 r = lzo1x_999_compress_internal(in, in_len, out, &out_len, wrkmem,
239 lazy, big, big, big, big, flags);
241 /* this should NEVER happen */
242 printf("internal error - compression failed: %d\n", r);
245 if (out_len < best_len) {
252 * Step 7: check if compressible
254 if (best_len >= in_len) {
255 printf("This file contains incompressible data.\n");
256 /* return 0; -- Sucks to be us -hpa ... */
260 * Step 8: compress data again using the best compressor found
262 out_len = out_bufsize;
263 r = lzo1x_999_compress_internal(in, in_len, out, &out_len, wrkmem,
265 best_lazy, big, big, big, big, flags);
266 assert(r == LZO_E_OK);
267 assert(out_len == best_len);
270 * Step 9: optimize compressed data (compressed data is in `out' buffer)
273 /* Optimization does not require any data in the buffer that will
274 * hold the uncompressed data. To prove this, we clear the buffer.
276 memset(in, 0, in_len);
280 r = lzo1x_optimize(out, out_len, in, &orig_len, NULL);
281 if (r != LZO_E_OK || orig_len != in_len) {
282 /* this should NEVER happen */
283 printf("internal error - optimization failed: %d\n", r);
288 * Step 10: compute a checksum of the compressed data
290 compressed_checksum = lzo_adler32(0, NULL, 0);
291 compressed_checksum = lzo_adler32(compressed_checksum, out, out_len);
294 * Step 11: write compressed data to a file
296 /* Make sure we have up to 2048 bytes of zero after the output */
297 memset(out + out_len, 0, 2048);
299 outfile_len = out_len;
301 soff = get_32(&prefix->pfx_cdatalen);
302 set_32((uint32_t *) (infile + soff), out_len);
304 soff = get_32(&prefix->pfx_checksum);
306 /* ISOLINUX padding and checksumming */
310 ((offset - start + out_len + 2047) & ~2047) - (offset - start);
311 for (ptr = 64; ptr < offset; ptr += 4)
312 csum += get_32((uint32_t *) (infile + ptr));
313 for (ptr = 0; ptr < outfile_len; ptr += 4)
314 csum += get_32((uint32_t *) (out + ptr));
316 set_32((uint32_t *) (infile + soff), offset - start + outfile_len);
317 set_32((uint32_t *) (infile + soff + 4), csum);
320 f = fopen(out_name, "wb");
322 printf("%s: cannot open output file %s\n", progname, out_name);
325 if (fwrite(infile + start, 1, offset - start, f) != offset - start ||
326 fwrite(out, 1, outfile_len, f) != outfile_len || fclose(f)) {
327 printf("%s: write error !!\n", progname);
332 * Step 12: verify decompression
335 test = calloc(in_len,2);
337 r = lzo1x_decompress_safe(out, out_len, test, &orig_len, NULL);
339 if (r != LZO_E_OK || orig_len != in_len) {
340 /* this should NEVER happen */
341 printf("internal error - decompression failed: %d\n", r);
344 if (memcmp(test, in, in_len)) {
345 /* this should NEVER happen */
346 printf("internal error - decompression data error\n");
349 /* Now you could also verify decompression under similar conditions as in
350 * your application, e.g. overlapping assembler decompression etc.