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+/* simple.c -- the annotated simple example program for the LZO library
+
+ This file is part of the LZO real-time data compression library.
+
+ Copyright (C) 2011 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2010 Markus Franz Xaver Johannes Oberhumer
+ Copyright (C) 2009 Markus Franz Xaver Johannes Oberhumer
+ 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/
+ */
+
+
+/*************************************************************************
+// This program shows the basic usage of the LZO library.
+// We will compress a block of data and decompress again.
+//
+// See also LZO.FAQ
+**************************************************************************/
+
+/* We will be using the LZO1X-1 algorithm, so we have
+ * to include <lzo1x.h>
+ */
+
+#include "lzo/lzoconf.h"
+#include "lzo/lzo1x.h"
+
+/* portability layer */
+static const char *progname = NULL;
+#define WANT_LZO_MALLOC 1
+#define WANT_XMALLOC 1
+#include "examples/portab.h"
+
+
+/* We want to compress the data block at 'in' with length 'IN_LEN' to
+ * the block at 'out'. Because the input block may be incompressible,
+ * we must provide a little more output space in case that compression
+ * is not possible.
+ */
+
+#ifndef IN_LEN
+#define IN_LEN (128*1024L)
+#endif
+#define OUT_LEN (IN_LEN + IN_LEN / 16 + 64 + 3)
+
+
+/*************************************************************************
+//
+**************************************************************************/
+
+int __lzo_cdecl_main main(int argc, char *argv[])
+{
+ int r;
+ lzo_bytep in;
+ lzo_bytep out;
+ lzo_voidp wrkmem;
+ lzo_uint in_len;
+ lzo_uint out_len;
+ lzo_uint new_len;
+
+ if (argc < 0 && argv == NULL) /* avoid warning about unused args */
+ return 0;
+
+ printf("\nLZO real-time data compression library (v%s, %s).\n",
+ lzo_version_string(), lzo_version_date());
+ printf("Copyright (C) 1996-2011 Markus Franz Xaver Johannes Oberhumer\nAll Rights Reserved.\n\n");
+
+/*
+ * 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");
+ return 4;
+ }
+
+/*
+ * Step 2: allocate blocks and the work-memory
+ */
+ in = (lzo_bytep) xmalloc(IN_LEN);
+ out = (lzo_bytep) xmalloc(OUT_LEN);
+ wrkmem = (lzo_voidp) xmalloc(LZO1X_1_MEM_COMPRESS);
+ if (in == NULL || out == NULL || wrkmem == NULL)
+ {
+ printf("out of memory\n");
+ return 3;
+ }
+
+/*
+ * Step 3: prepare the input block that will get compressed.
+ * We just fill it with zeros in this example program,
+ * but you would use your real-world data here.
+ */
+ in_len = IN_LEN;
+ lzo_memset(in,0,in_len);
+
+/*
+ * Step 4: compress from 'in' to 'out' with LZO1X-1
+ */
+ r = lzo1x_1_compress(in,in_len,out,&out_len,wrkmem);
+ if (r == LZO_E_OK)
+ printf("compressed %lu bytes into %lu bytes\n",
+ (unsigned long) in_len, (unsigned long) out_len);
+ else
+ {
+ /* this should NEVER happen */
+ printf("internal error - compression failed: %d\n", r);
+ return 2;
+ }
+ /* check for an incompressible block */
+ if (out_len >= in_len)
+ {
+ printf("This block contains incompressible data.\n");
+ return 0;
+ }
+
+/*
+ * Step 5: decompress again, now going from 'out' to 'in'
+ */
+ new_len = in_len;
+ r = lzo1x_decompress(out,out_len,in,&new_len,NULL);
+ if (r == LZO_E_OK && new_len == in_len)
+ printf("decompressed %lu bytes back into %lu bytes\n",
+ (unsigned long) out_len, (unsigned long) in_len);
+ else
+ {
+ /* this should NEVER happen */
+ printf("internal error - decompression failed: %d\n", r);
+ return 1;
+ }
+
+ lzo_free(wrkmem);
+ lzo_free(out);
+ lzo_free(in);
+ printf("Simple compression test passed.\n");
+ return 0;
+}
+
+/*
+vi:ts=4:et
+*/
+