Create the compress module for compression functions.

For the moment there is only the lzxpress compression used by DRS

Bug: 10546
Change-Id: Ifc7e1767934224c0198f0b09caa3efbad979ca1f
Reviewed-on: https://code.wireshark.org/review/4600
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Michael Mann <mmann78@netscape.net>

1 files changed, 136 insertions, 0 deletions

diff --git a/epan/compress/lzxpress.c b/epan/compress/lzxpress.c
new file mode 100644
index 0000000000..2e8883a407
--- /dev/null
+++ b/epan/compress/lzxpress.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) Matthieu Suiche 2008
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the author nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#include "lzxpress.h"
+
+#define __BUF_POS_CONST(buf,ofs)(((const guint8 *)buf)+(ofs))
+#define __PULL_BYTE(buf,ofs) \
+	((guint8)((*__BUF_POS_CONST(buf,ofs)) & 0xFF))
+
+#ifndef PULL_LE_UINT16
+#define PULL_LE_UINT16(buf,ofs) ((guint16)( \
+	((guint16)(((guint16)(__PULL_BYTE(buf,(ofs)+0))) << 0)) | \
+	((guint16)(((guint16)(__PULL_BYTE(buf,(ofs)+1))) << 8)) \
+))
+#endif
+
+#ifndef PULL_LE_UINT32
+#define PULL_LE_UINT32(buf,ofs) ((guint32)( \
+	((guint32)(((guint32)(__PULL_BYTE(buf,(ofs)+0))) <<  0)) | \
+	((guint32)(((guint32)(__PULL_BYTE(buf,(ofs)+1))) <<  8)) | \
+	((guint32)(((guint32)(__PULL_BYTE(buf,(ofs)+2))) << 16)) | \
+	((guint32)(((guint32)(__PULL_BYTE(buf,(ofs)+3))) << 24)) \
+))
+#endif
+
+gssize lzxpress_decompress(const guint8 *input,
+			    guint32 input_size,
+			    guint8 *output,
+			    guint32 max_output_size)
+{
+	guint32 output_index, input_index;
+	guint32 indicator, indicator_bit;
+	guint32 length;
+	guint32 offset;
+	guint32 nibble_index;
+
+	output_index = 0;
+	input_index = 0;
+	indicator = 0;
+	indicator_bit = 0;
+	length = 0;
+	offset = 0;
+	nibble_index = 0;
+
+	do {
+		if (indicator_bit == 0) {
+			indicator = PULL_LE_UINT32(input, input_index);
+			input_index += sizeof(guint32);
+			indicator_bit = 32;
+		}
+		indicator_bit--;
+
+		/*
+		 * check whether the bit specified by indicator_bit is set or not
+		 * set in indicator. For example, if indicator_bit has value 4
+		 * check whether the 4th bit of the value in indicator is set
+		 */
+		if (((indicator >> indicator_bit) & 1) == 0) {
+			output[output_index] = input[input_index];
+			input_index += sizeof(guint8);
+			output_index += sizeof(guint8);
+		} else {
+			length = PULL_LE_UINT16(input, input_index);
+			input_index += sizeof(guint16);
+			offset = length / 8;
+			length = length % 8;
+
+			if (length == 7) {
+				if (nibble_index == 0) {
+					nibble_index = input_index;
+					length = input[input_index] % 16;
+					input_index += sizeof(guint8);
+				} else {
+					length = input[nibble_index] / 16;
+					nibble_index = 0;
+				}
+
+				if (length == 15) {
+					length = input[input_index];
+					input_index += sizeof(guint8);
+					if (length == 255) {
+						length = PULL_LE_UINT16(input, input_index);
+						input_index += sizeof(guint16);
+						length -= (15 + 7);
+					}
+					length += 15;
+				}
+				length += 7;
+			}
+
+			length += 3;
+
+			do {
+				if ((output_index >= max_output_size) || ((offset + 1) > output_index)) break;
+
+				output[output_index] = output[output_index - offset - 1];
+
+				output_index += sizeof(guint8);
+				length -= sizeof(guint8);
+			} while (length != 0);
+		}
+	} while ((output_index < max_output_size) && (input_index < (input_size)));
+
+	return output_index;
+}