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diff --git a/examples/lzopack.c b/examples/lzopack.c
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+/* lzopack.c -- LZO example program: a simple file packer
+
+ This file is part of the LZO real-time data compression library.
+
+ Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
+ All Rights Reserved.
+
+ The LZO library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2 of
+ the License, or (at your option) any later version.
+
+ The LZO library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with the LZO library; see the file COPYING.
+ If not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+ Markus F.X.J. Oberhumer
+ <markus@oberhumer.com>
+ http://www.oberhumer.com/opensource/lzo/
+ */
+
+
+/*************************************************************************
+// NOTE: this is an example program, so do not use to backup your data.
+//
+// This program lacks things like sophisticated file handling but is
+// pretty complete regarding compression - it should provide a good
+// starting point for adaption for your applications.
+//
+// Please study LZO.FAQ and simple.c first.
+**************************************************************************/
+
+#include "lzo/lzoconf.h"
+#include "lzo/lzo1x.h"
+
+/* portability layer */
+#define WANT_LZO_MALLOC 1
+#define WANT_LZO_FREAD 1
+#define WANT_LZO_WILDARGV 1
+#include "examples/portab.h"
+
+
+static const char *progname = NULL;
+
+static unsigned long total_in = 0;
+static unsigned long total_out = 0;
+static lzo_bool opt_debug = 0;
+
+/* magic file header for lzopack-compressed files */
+static const unsigned char magic[7] =
+ { 0x00, 0xe9, 0x4c, 0x5a, 0x4f, 0xff, 0x1a };
+
+
+/*************************************************************************
+// file IO
+**************************************************************************/
+
+lzo_uint xread(FILE *fp, lzo_voidp buf, lzo_uint len, lzo_bool allow_eof)
+{
+ lzo_uint l;
+
+ l = (lzo_uint) lzo_fread(fp, buf, len);
+ if (l > len)
+ {
+ fprintf(stderr, "\nsomething's wrong with your C library !!!\n");
+ exit(1);
+ }
+ if (l != len && !allow_eof)
+ {
+ fprintf(stderr, "\nread error - premature end of file\n");
+ exit(1);
+ }
+ total_in += (unsigned long) l;
+ return l;
+}
+
+lzo_uint xwrite(FILE *fp, const lzo_voidp buf, lzo_uint len)
+{
+ if (fp != NULL && lzo_fwrite(fp, buf, len) != len)
+ {
+ fprintf(stderr, "\nwrite error (disk full ?)\n");
+ exit(1);
+ }
+ total_out += (unsigned long) len;
+ return len;
+}
+
+
+int xgetc(FILE *fp)
+{
+ unsigned char c;
+ xread(fp, (lzo_voidp) &c, 1, 0);
+ return c;
+}
+
+void xputc(FILE *fp, int c)
+{
+ unsigned char cc = (unsigned char) (c & 0xff);
+ xwrite(fp, (const lzo_voidp) &cc, 1);
+}
+
+/* read and write portable 32-bit integers */
+
+lzo_uint32 xread32(FILE *fp)
+{
+ unsigned char b[4];
+ lzo_uint32 v;
+
+ xread(fp, b, 4, 0);
+ v = (lzo_uint32) b[3] << 0;
+ v |= (lzo_uint32) b[2] << 8;
+ v |= (lzo_uint32) b[1] << 16;
+ v |= (lzo_uint32) b[0] << 24;
+ return v;
+}
+
+void xwrite32(FILE *fp, lzo_xint v)
+{
+ unsigned char b[4];
+
+ b[3] = (unsigned char) ((v >> 0) & 0xff);
+ b[2] = (unsigned char) ((v >> 8) & 0xff);
+ b[1] = (unsigned char) ((v >> 16) & 0xff);
+ b[0] = (unsigned char) ((v >> 24) & 0xff);
+ xwrite(fp, b, 4);
+}
+
+
+/*************************************************************************
+// compress
+//
+// possible improvement: we could use overlapping compression to
+// save some memory - see overlap.c. This would require some minor
+// changes in the decompression code as well, because if a block
+// turns out to be incompressible we would still have to store it in its
+// "compressed" (i.e. then slightly enlarged) form because the original
+// (uncompressed) data would have been lost during the overlapping
+// compression.
+**************************************************************************/
+
+int do_compress(FILE *fi, FILE *fo, int level, lzo_uint block_size)
+{
+ int r = 0;
+ lzo_bytep in = NULL;
+ lzo_bytep out = NULL;
+ lzo_bytep wrkmem = NULL;
+ lzo_uint in_len;
+ lzo_uint out_len;
+ lzo_uint32 wrk_len = 0;
+ lzo_uint32 flags = 1; /* do compute a checksum */
+ int method = 1; /* compression method: LZO1X */
+ lzo_uint32 checksum;
+
+ total_in = total_out = 0;
+
+/*
+ * Step 1: write magic header, flags & block size, init checksum
+ */
+ xwrite(fo, magic, sizeof(magic));
+ xwrite32(fo, flags);
+ xputc(fo, method); /* compression method */
+ xputc(fo, level); /* compression level */
+ xwrite32(fo, block_size);
+ checksum = lzo_adler32(0, NULL, 0);
+
+/*
+ * Step 2: allocate compression buffers and work-memory
+ */
+ in = (lzo_bytep) lzo_malloc(block_size);
+ out = (lzo_bytep) lzo_malloc(block_size + block_size / 16 + 64 + 3);
+ if (level == 9)
+ wrk_len = LZO1X_999_MEM_COMPRESS;
+ else
+ wrk_len = LZO1X_1_MEM_COMPRESS;
+ wrkmem = (lzo_bytep) lzo_malloc(wrk_len);
+ if (in == NULL || out == NULL || wrkmem == NULL)
+ {
+ printf("%s: out of memory\n", progname);
+ r = 1;
+ goto err;
+ }
+
+/*
+ * Step 3: process blocks
+ */
+ for (;;)
+ {
+ /* read block */
+ in_len = xread(fi, in, block_size, 1);
+ if (in_len <= 0)
+ break;
+
+ /* update checksum */
+ if (flags & 1)
+ checksum = lzo_adler32(checksum, in, in_len);
+
+ /* clear wrkmem (not needed, only for debug/benchmark purposes) */
+ if (opt_debug)
+ lzo_memset(wrkmem, 0xff, wrk_len);
+
+ /* compress block */
+ if (level == 9)
+ r = lzo1x_999_compress(in, in_len, out, &out_len, wrkmem);
+ else
+ r = lzo1x_1_compress(in, in_len, out, &out_len, wrkmem);
+ if (r != LZO_E_OK || out_len > in_len + in_len / 16 + 64 + 3)
+ {
+ /* this should NEVER happen */
+ printf("internal error - compression failed: %d\n", r);
+ r = 2;
+ goto err;
+ }
+
+ /* write uncompressed block size */
+ xwrite32(fo, in_len);
+
+ if (out_len < in_len)
+ {
+ /* write compressed block */
+ xwrite32(fo, out_len);
+ xwrite(fo, out, out_len);
+ }
+ else
+ {
+ /* not compressible - write uncompressed block */
+ xwrite32(fo, in_len);
+ xwrite(fo, in, in_len);
+ }
+ }
+
+ /* write EOF marker */
+ xwrite32(fo, 0);
+
+ /* write checksum */
+ if (flags & 1)
+ xwrite32(fo, checksum);
+
+ r = 0;
+err:
+ lzo_free(wrkmem);
+ lzo_free(out);
+ lzo_free(in);
+ return r;
+}
+
+
+/*************************************************************************
+// decompress / test
+//
+// We are using overlapping (in-place) decompression to save some
+// memory - see overlap.c.
+**************************************************************************/
+
+int do_decompress(FILE *fi, FILE *fo)
+{
+ int r = 0;
+ lzo_bytep buf = NULL;
+ lzo_uint buf_len;
+ unsigned char m [ sizeof(magic) ];
+ lzo_uint32 flags;
+ int method;
+ int level;
+ lzo_uint block_size;
+ lzo_uint32 checksum;
+
+ total_in = total_out = 0;
+
+/*
+ * Step 1: check magic header, read flags & block size, init checksum
+ */
+ if (xread(fi, m, sizeof(magic),1) != sizeof(magic) ||
+ memcmp(m, magic, sizeof(magic)) != 0)
+ {
+ printf("%s: header error - this file is not compressed by lzopack\n", progname);
+ r = 1;
+ goto err;
+ }
+ flags = xread32(fi);
+ method = xgetc(fi);
+ level = xgetc(fi);
+ if (method != 1)
+ {
+ printf("%s: header error - invalid method %d (level %d)\n",
+ progname, method, level);
+ r = 2;
+ goto err;
+ }
+ block_size = xread32(fi);
+ if (block_size < 1024 || block_size > 8*1024*1024L)
+ {
+ printf("%s: header error - invalid block size %ld\n",
+ progname, (long) block_size);
+ r = 3;
+ goto err;
+ }
+ checksum = lzo_adler32(0,NULL,0);
+
+/*
+ * Step 2: allocate buffer for in-place decompression
+ */
+ buf_len = block_size + block_size / 16 + 64 + 3;
+ buf = (lzo_bytep) lzo_malloc(buf_len);
+ if (buf == NULL)
+ {
+ printf("%s: out of memory\n", progname);
+ r = 4;
+ goto err;
+ }
+
+/*
+ * Step 3: process blocks
+ */
+ for (;;)
+ {
+ lzo_bytep in;
+ lzo_bytep out;
+ lzo_uint in_len;
+ lzo_uint out_len;
+
+ /* read uncompressed size */
+ out_len = xread32(fi);
+
+ /* exit if last block (EOF marker) */
+ if (out_len == 0)
+ break;
+
+ /* read compressed size */
+ in_len = xread32(fi);
+
+ /* sanity check of the size values */
+ if (in_len > block_size || out_len > block_size ||
+ in_len == 0 || in_len > out_len)
+ {
+ printf("%s: block size error - data corrupted\n", progname);
+ r = 5;
+ goto err;
+ }
+
+ /* place compressed block at the top of the buffer */
+ in = buf + buf_len - in_len;
+ out = buf;
+
+ /* read compressed block data */
+ xread(fi, in, in_len, 0);
+
+ if (in_len < out_len)
+ {
+ /* decompress - use safe decompressor as data might be corrupted
+ * during a file transfer */
+ lzo_uint new_len = out_len;
+
+ r = lzo1x_decompress_safe(in, in_len, out, &new_len, NULL);
+ if (r != LZO_E_OK || new_len != out_len)
+ {
+ printf("%s: compressed data violation\n", progname);
+ r = 6;
+ goto err;
+ }
+ /* write decompressed block */
+ xwrite(fo, out, out_len);
+ /* update checksum */
+ if (flags & 1)
+ checksum = lzo_adler32(checksum, out, out_len);
+ }
+ else
+ {
+ /* write original (incompressible) block */
+ xwrite(fo, in, in_len);
+ /* update checksum */
+ if (flags & 1)
+ checksum = lzo_adler32(checksum, in, in_len);
+ }
+ }
+
+ /* read and verify checksum */
+ if (flags & 1)
+ {
+ lzo_uint32 c = xread32(fi);
+ if (c != checksum)
+ {
+ printf("%s: checksum error - data corrupted\n", progname);
+ r = 7;
+ goto err;
+ }
+ }
+
+ r = 0;
+err:
+ lzo_free(buf);
+ return r;
+}
+
+
+/*************************************************************************
+//
+**************************************************************************/
+
+static void usage(void)
+{
+ printf("usage: %s [-9] input-file output-file (compress)\n", progname);
+ printf("usage: %s -d input-file output-file (decompress)\n", progname);
+ printf("usage: %s -t input-file... (test)\n", progname);
+ exit(1);
+}
+
+
+/* open input file */
+static FILE *xopen_fi(const char *name)
+{
+ FILE *fp;
+
+ fp = fopen(name, "rb");
+ if (fp == NULL)
+ {
+ printf("%s: cannot open input file %s\n", progname, name);
+ exit(1);
+ }
+#if defined(HAVE_STAT) && defined(S_ISREG)
+ {
+ struct stat st;
+ int is_regular = 1;
+ if (stat(name, &st) != 0 || !S_ISREG(st.st_mode))
+ is_regular = 0;
+ if (!is_regular)
+ {
+ printf("%s: %s is not a regular file\n", progname, name);
+ fclose(fp); fp = NULL;
+ exit(1);
+ }
+ }
+#endif
+ return fp;
+}
+
+
+/* open output file */
+static FILE *xopen_fo(const char *name)
+{
+ FILE *fp;
+
+#if 0
+ /* this is an example program, so make sure we don't overwrite a file */
+ fp = fopen(name, "rb");
+ if (fp != NULL)
+ {
+ printf("%s: file %s already exists -- not overwritten\n", progname, name);
+ fclose(fp); fp = NULL;
+ exit(1);
+ }
+#endif
+ fp = fopen(name, "wb");
+ if (fp == NULL)
+ {
+ printf("%s: cannot open output file %s\n", progname, name);
+ exit(1);
+ }
+ return fp;
+}
+
+
+/* close file */
+static void xclose(FILE *fp)
+{
+ if (fp)
+ {
+ int err;
+ err = ferror(fp);
+ if (fclose(fp) != 0)
+ err = 1;
+ if (err)
+ {
+ printf("%s: error while closing file\n", progname);
+ exit(1);
+ }
+ }
+}
+
+
+/*************************************************************************
+//
+**************************************************************************/
+
+int __lzo_cdecl_main main(int argc, char *argv[])
+{
+ int i = 1;
+ int r = 0;
+ FILE *fi = NULL;
+ FILE *fo = NULL;
+ const char *in_name = NULL;
+ const char *out_name = NULL;
+ lzo_bool opt_decompress = 0;
+ lzo_bool opt_test = 0;
+ int opt_level = 1;
+ lzo_uint opt_block_size;
+ const char *s;
+
+ lzo_wildargv(&argc, &argv);
+
+ progname = argv[0];
+ for (s = progname; *s; s++)
+ if ((*s == '/' || *s == '\\') && s[1])
+ progname = s + 1;
+
+ printf("\nLZO real-time data compression library (v%s, %s).\n",
+ lzo_version_string(), lzo_version_date());
+ printf("Copyright (C) 1996-2008 Markus Franz Xaver Johannes Oberhumer\nAll Rights Reserved.\n\n");
+
+#if 0
+ printf(
+"*** DISCLAIMER ***\n"
+" This is an example program, do not use to backup your data !\n"
+" Get LZOP if you're interested into a full-featured packer.\n"
+" See http://www.oberhumer.com/opensource/lzop/\n"
+"\n");
+#endif
+
+
+/*
+ * Step 1: initialize the LZO library
+ */
+ if (lzo_init() != LZO_E_OK)
+ {
+ printf("internal error - lzo_init() failed !!!\n");
+ printf("(this usually indicates a compiler bug - try recompiling\nwithout optimizations, and enable `-DLZO_DEBUG' for diagnostics)\n");
+ exit(1);
+ }
+
+
+/*
+ * Step 2: setup memory
+ */
+ opt_block_size = 256 * 1024L;
+
+#if defined(ACC_MM_AHSHIFT)
+ /* reduce memory requirements for ancient 16-bit DOS 640kB real-mode */
+ if (ACC_MM_AHSHIFT != 3)
+ opt_block_size = 16 * 1024L;
+#endif
+
+
+/*
+ * Step 3: get options
+ */
+
+ while (i < argc && argv[i][0] == '-')
+ {
+ if (strcmp(argv[i],"-d") == 0)
+ opt_decompress = 1;
+ else if (strcmp(argv[i],"-t") == 0)
+ opt_test = 1;
+ else if (strcmp(argv[i],"-9") == 0)
+ opt_level = 9;
+ else if (argv[i][1] == 'b' && argv[i][2])
+ {
+ long b = atol(&argv[i][2]);
+ if (b >= 1024L && b <= 8*1024*1024L)
+ opt_block_size = (lzo_uint) b;
+ else
+ {
+ printf("%s: invalid block_size in option `%s'.\n", progname, argv[i]);
+ usage();
+ }
+ }
+ else if (strcmp(argv[i],"--debug") == 0)
+ opt_debug += 1;
+ else
+ usage();
+ i++;
+ }
+ if (opt_test && i >= argc)
+ usage();
+ if (!opt_test && i + 2 != argc)
+ usage();
+
+
+/*
+ * Step 4: process file(s)
+ */
+
+ if (opt_test)
+ {
+ while (i < argc && r == 0)
+ {
+ in_name = argv[i++];
+ fi = xopen_fi(in_name);
+ r = do_decompress(fi, NULL);
+ if (r == 0)
+ printf("%s: %s tested ok (%lu -> %lu bytes)\n",
+ progname, in_name, total_in, total_out);
+ xclose(fi); fi = NULL;
+ }
+ }
+ else if (opt_decompress)
+ {
+ in_name = argv[i++];
+ out_name = argv[i++];
+ fi = xopen_fi(in_name);
+ fo = xopen_fo(out_name);
+ r = do_decompress(fi, fo);
+ if (r == 0)
+ printf("%s: decompressed %lu into %lu bytes\n",
+ progname, total_in, total_out);
+ }
+ else /* compress */
+ {
+ in_name = argv[i++];
+ out_name = argv[i++];
+ fi = xopen_fi(in_name);
+ fo = xopen_fo(out_name);
+ r = do_compress(fi, fo, opt_level, opt_block_size);
+ if (r == 0)
+ printf("%s: compressed %lu into %lu bytes\n",
+ progname, total_in, total_out);
+ }
+
+ xclose(fi); fi = NULL;
+ xclose(fo); fo = NULL;
+ return r;
+}
+
+/*
+vi:ts=4:et
+*/
+
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