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diff --git a/lzo/examples/overlap.c b/lzo/examples/overlap.c
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+/* overlap.c -- example program: overlapping (de)compression
+
+   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/
+ */
+
+
+/*************************************************************************
+// This program shows how to do overlapping compression and
+// in-place decompression.
+//
+// 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"
+
+
+/* Overhead (in bytes) for the in-place decompression buffer.
+ * Most files need only 16 !
+ * (try `overlap -16 file' or even `overlap -8 file')
+ *
+ * Worst case (for files that are compressible by only a few bytes)
+ * is 'in_len / 16 + 64 + 3'. See step 5a) below.
+ *
+ * For overlapping compression '0xbfff + in_len / 16 + 64 + 3' bytes
+ * will be needed. See step 4a) below.
+ */
+
+static lzo_uint opt_overhead = 0;   /* assume worst case */
+
+
+#if 0 && defined(LZO_USE_ASM)
+   /* just for testing */
+#  include <lzo_asm.h>
+#  define lzo1x_decompress lzo1x_decompress_asm_fast
+#endif
+
+
+/*************************************************************************
+//
+**************************************************************************/
+
+static const char *progname = NULL;
+
+static unsigned long total_files = 0;
+static unsigned long total_in = 0;
+
+
+static lzo_bytep xmalloc(lzo_uint len)
+{
+    lzo_bytep p;
+
+    p = (lzo_bytep) lzo_malloc(len > 0 ? len : 1);
+    if (p == NULL)
+    {
+        printf("%s: out of memory\n", progname);
+        exit(1);
+    }
+    return p;
+}
+
+
+/*************************************************************************
+//
+**************************************************************************/
+
+int do_file ( const char *in_name )
+{
+    int r;
+    FILE *f = NULL;
+    long l;
+
+    lzo_bytep wrkmem = NULL;
+
+    lzo_bytep in = NULL;
+    lzo_uint in_len;                /* uncompressed length */
+
+    lzo_bytep out = NULL;
+    lzo_uint out_len;               /* compressed length */
+
+    lzo_bytep overlap = NULL;
+    lzo_uint overhead;
+    lzo_uint offset;
+
+    lzo_uint new_len = 0;
+
+/*
+ * Step 1: open the input file
+ */
+    f = fopen(in_name,"rb");
+    if (f == NULL)
+    {
+        printf("%s: %s: cannot open file\n", progname, in_name);
+        goto next_file;
+    }
+    fseek(f,0,SEEK_END);
+    l = ftell(f);
+    fseek(f,0,SEEK_SET);
+    if (l <= 0)
+    {
+        printf("%s: %s: empty file -- skipping\n", progname, in_name);
+        goto next_file;
+    }
+    in_len = (lzo_uint) l;
+
+/*
+ * Step 2: allocate compression buffers and read the file
+ */
+    in = xmalloc(in_len);
+    out = xmalloc(in_len + in_len / 16 + 64 + 3);
+    wrkmem = xmalloc(LZO1X_1_MEM_COMPRESS);
+    in_len = (lzo_uint) lzo_fread(f,in,in_len);
+    fclose(f); f = NULL;
+    printf("%s: %s: read %ld bytes\n", progname, in_name, (long) in_len);
+
+    total_files++;
+    total_in += (unsigned long) in_len;
+
+/*
+ * Step 3: compress from `in' to `out' with LZO1X-1
+ */
+    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);
+        exit(1);
+    }
+    printf("%-26s %8lu -> %8lu\n", "LZO1X-1:", (long) in_len, (long) out_len);
+
+
+/***** Step 4: overlapping compression *****/
+
+/*
+ * Step 4a: allocate the `overlap' buffer for overlapping compression
+ */
+    overhead  = in_len > 0xbfff ? 0xbfff : in_len;
+    overhead += in_len / 16 + 64 + 3;
+    overlap = xmalloc(in_len + overhead);
+
+/*
+ * Step 4b: prepare data in `overlap' buffer.
+ *          copy uncompressed data at the top of the overlap buffer
+ */
+    /*** offset = in_len + overhead - in_len; ***/
+    offset = overhead;
+    lzo_memcpy(overlap + offset, in, in_len);
+
+/*
+ * Step 4c: do an in-place compression within the `overlap' buffer
+ */
+    r = lzo1x_1_compress(overlap+offset,in_len,overlap,&new_len,wrkmem);
+    if (r != LZO_E_OK)
+    {
+        /* this should NEVER happen */
+        printf("overlapping compression failed: %d\n", r);
+        exit(1);
+    }
+
+/*
+ * Step 4d: verify overlapping compression
+ */
+    if (new_len != out_len || lzo_memcmp(out,overlap,out_len) != 0)
+    {
+        /* As compression is non-deterministic there can be a difference
+         * in the representation of the compressed data (but this usually
+         * happens very seldom). So we have to verify the overlapping
+         * compression by doing a temporary decompression.
+         */
+        lzo_uint l = in_len;
+        lzo_bytep tmp = xmalloc(l);
+        r = lzo1x_decompress_safe(overlap,new_len,tmp,&l,NULL);
+        if (r != LZO_E_OK || l != in_len || lzo_memcmp(in,tmp,l) != 0)
+        {
+            /* this should NEVER happen */
+            printf("overlapping compression data error\n");
+            exit(1);
+        }
+        lzo_free(tmp);
+    }
+
+    printf("overlapping compression:   %8lu -> %8lu    overhead: %7ld\n",
+            (long) in_len, (long) new_len, (long) overhead);
+    lzo_free(overlap); overlap = NULL;
+
+
+/***** Step 5: overlapping decompression *****/
+
+/*
+ * Step 5a: allocate the `overlap' buffer for in-place decompression
+ */
+    if (opt_overhead == 0 || out_len >= in_len)
+        overhead = in_len / 16 + 64 + 3;
+    else
+        overhead = opt_overhead;
+    overlap = xmalloc(in_len + overhead);
+
+/*
+ * Step 5b: prepare data in `overlap' buffer.
+ *          copy compressed data at the top of the overlap buffer
+ */
+    offset = in_len + overhead - out_len;
+    lzo_memcpy(overlap + offset, out, out_len);
+
+/*
+ * Step 5c: do an in-place decompression within the `overlap' buffer
+ */
+    new_len = in_len;
+    r = lzo1x_decompress(overlap+offset,out_len,overlap,&new_len,NULL);
+    if (r != LZO_E_OK)
+    {
+        /* this may happen if overhead is too small */
+        printf("overlapping decompression failed: %d - increase `opt_overhead'\n", r);
+        exit(1);
+    }
+
+/*
+ * Step 5d: verify decompression
+ */
+    if (new_len != in_len || lzo_memcmp(in,overlap,in_len) != 0)
+    {
+        /* this may happen if overhead is too small */
+        printf("overlapping decompression data error - increase `opt_overhead'\n");
+        exit(1);
+    }
+    printf("overlapping decompression: %8lu -> %8lu    overhead: %7ld\n",
+            (long) out_len, (long) new_len, (long) overhead);
+    lzo_free(overlap); overlap = NULL;
+
+
+next_file:
+    lzo_free(overlap);
+    lzo_free(wrkmem);
+    lzo_free(out);
+    lzo_free(in);
+    if (f) fclose(f);
+
+    return 0;
+}
+
+
+/*************************************************************************
+//
+**************************************************************************/
+
+int __lzo_cdecl_main main(int argc, char *argv[])
+{
+    int r;
+    int i = 1;
+
+    lzo_wildargv(&argc, &argv);
+
+    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");
+
+    progname = argv[0];
+    if (i < argc && argv[i][0] == '-')
+        opt_overhead = atoi(&argv[i++][1]);
+#if 1
+    if (opt_overhead != 0 && opt_overhead < 8)
+    {
+        printf("%s: invalid overhead value %ld\n", progname, (long)opt_overhead);
+        exit(1);
+    }
+#endif
+    if (i >= argc)
+    {
+        printf("usage: %s [-overhead_in_bytes] file..\n", progname);
+        exit(1);
+    }
+
+/*
+ * 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: process files
+ */
+    for (r = 0; r == 0 && i < argc; i++)
+        r = do_file(argv[i]);
+
+    printf("\nDone. Successfully processed %lu bytes in %lu files.\n",
+            total_in, total_files);
+    return r;
+}
+
+/*
+vi:ts=4:et
+*/
+