Merge branch 'master' of ssh://git.samba.org/data/git/samba into noejs

Conflicts:
	source4/main.mk

1 files changed, 312 insertions, 0 deletions

diff --git a/lib/compression/lzxpress.c b/lib/compression/lzxpress.c
new file mode 100644
index 0000000000..0abbfc4d3d
--- /dev/null
+++ b/lib/compression/lzxpress.c
@@ -0,0 +1,312 @@
+/*
+ * 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 "replace.h"
+#include "lzxpress.h"
+
+
+#define __BUF_POS_CONST(buf,ofs)(((const uint8_t *)buf)+(ofs))
+#define __PULL_BYTE(buf,ofs) \
+	((uint8_t)((*__BUF_POS_CONST(buf,ofs)) & 0xFF))
+
+#ifndef PULL_LE_UINT16
+#define PULL_LE_UINT16(buf,ofs) ((uint16_t)( \
+	((uint16_t)(((uint16_t)(__PULL_BYTE(buf,(ofs)+0))) << 0)) | \
+	((uint16_t)(((uint16_t)(__PULL_BYTE(buf,(ofs)+1))) << 8)) \
+))
+#endif
+
+#ifndef PULL_LE_UINT32
+#define PULL_LE_UINT32(buf,ofs) ((uint32_t)( \
+	((uint32_t)(((uint32_t)(__PULL_BYTE(buf,(ofs)+0))) <<  0)) | \
+	((uint32_t)(((uint32_t)(__PULL_BYTE(buf,(ofs)+1))) <<  8)) | \
+	((uint32_t)(((uint32_t)(__PULL_BYTE(buf,(ofs)+2))) << 16)) | \
+	((uint32_t)(((uint32_t)(__PULL_BYTE(buf,(ofs)+3))) << 24)) \
+))
+#endif
+
+ssize_t lzxpress_compress(const uint8_t *uncompressed,
+			  uint32_t uncompressed_size,
+			  uint8_t *compressed,
+			  uint32_t max_compressed_size)
+{
+	uint32_t uncompressed_pos, compressed_pos, byte_left;
+	uint32_t max_offset, best_offset;
+	int32_t offset;
+	uint32_t max_len, len, best_len;
+	const uint8_t *str1, *str2;
+	uint32_t indic;
+	uint8_t *indic_pos;
+	uint32_t indic_bit, nibble_index;
+
+	uint32_t metadata_size;
+	uint16_t metadata;
+	uint16_t *dest;
+
+	if (!uncompressed_size) {
+		return 0;
+	}
+
+	uncompressed_pos = 0;
+	indic = 0;
+	compressed_pos = sizeof(uint32_t);
+	indic_pos = &compressed[0];
+
+	byte_left = uncompressed_size;
+	indic_bit = 0;
+	nibble_index = 0;
+
+	if (uncompressed_pos > XPRESS_BLOCK_SIZE)
+		return 0;
+
+	do {
+		bool found = false;
+
+		max_offset = uncompressed_pos;
+
+		str1 = &uncompressed[uncompressed_pos];
+
+		best_len = 2;
+		best_offset = 0;
+
+		max_offset = MIN(0x1FFF, max_offset);
+
+		/* search for the longest match in the window for the lookahead buffer */
+		for (offset = 1; (uint32_t)offset <= max_offset; offset++) {
+			str2 = &str1[-offset];
+
+			/* maximum len we can encode into metadata */
+			max_len = MIN((255 + 15 + 7 + 3), byte_left);
+
+			for (len = 0; (len < max_len) && (str1[len] == str2[len]); len++);
+
+			/*
+			 * We check if len is better than the value found before, including the
+			 * sequence of identical bytes
+			 */
+			if (len > best_len) {
+				found = true;
+				best_len = len;
+				best_offset = offset;
+			}
+		}
+
+		if (found) {
+			metadata_size = 0;
+			dest = (uint16_t *)&compressed[compressed_pos];
+
+			if (best_len < 10) {
+				/* Classical meta-data */
+				metadata = (uint16_t)(((best_offset - 1) << 3) | (best_len - 3));
+				dest[metadata_size / sizeof(uint16_t)] = metadata;
+				metadata_size += sizeof(uint16_t);
+			} else {
+				metadata = (uint16_t)(((best_offset - 1) << 3) | 7);
+				dest[metadata_size / sizeof(uint16_t)] = metadata;
+				metadata_size = sizeof(uint16_t);
+
+				if (best_len < (15 + 7 + 3)) {
+					/* Shared byte */
+					if (!nibble_index) {
+						compressed[compressed_pos + metadata_size] = (best_len - (3 + 7)) & 0xF;
+						metadata_size += sizeof(uint8_t);
+					} else {
+						compressed[nibble_index] &= 0xF;
+						compressed[nibble_index] |= (best_len - (3 + 7)) * 16;
+					}
+				} else if (best_len < (3 + 7 + 15 + 255)) {
+					/* Shared byte */
+					if (!nibble_index) {
+						compressed[compressed_pos + metadata_size] = 15;
+						metadata_size += sizeof(uint8_t);
+					} else {
+						compressed[nibble_index] &= 0xF;
+						compressed[nibble_index] |= (15 * 16);
+					}
+
+					/* Additionnal best_len */
+					compressed[compressed_pos + metadata_size] = (best_len - (3 + 7 + 15)) & 0xFF;
+					metadata_size += sizeof(uint8_t);
+				} else {
+					/* Shared byte */
+					if (!nibble_index) {
+						compressed[compressed_pos + metadata_size] |= 15;
+						metadata_size += sizeof(uint8_t);
+					} else {
+						compressed[nibble_index] |= 15 << 4;
+					}
+
+					/* Additionnal best_len */
+					compressed[compressed_pos + metadata_size] = 255;
+
+					metadata_size += sizeof(uint8_t);
+
+					compressed[compressed_pos + metadata_size] = (best_len - 3) & 0xFF;
+					compressed[compressed_pos + metadata_size + 1] = ((best_len - 3) >> 8) & 0xFF;
+					metadata_size += sizeof(uint16_t);
+				}
+			}
+
+			indic |= 1 << (32 - ((indic_bit % 32) + 1));
+
+			if (best_len > 9) {
+				if (nibble_index == 0) {
+					nibble_index = compressed_pos + sizeof(uint16_t);
+				} else {
+					nibble_index = 0;
+				}
+			}
+
+			compressed_pos += metadata_size;
+			uncompressed_pos += best_len;
+			byte_left -= best_len;
+		} else {
+			compressed[compressed_pos++] = uncompressed[uncompressed_pos++];
+			byte_left--;
+		}
+		indic_bit++;
+
+		if ((indic_bit - 1) % 32 > (indic_bit % 32)) {
+			*(uint32_t *)indic_pos = indic;
+			indic = 0;
+			indic_pos = &compressed[compressed_pos];
+			compressed_pos += sizeof(uint32_t);
+		}
+	} while (byte_left > 3);
+
+	do {
+		compressed[compressed_pos] = uncompressed[uncompressed_pos];
+		indic_bit++;
+
+		uncompressed_pos++;
+		compressed_pos++;
+                if (((indic_bit - 1) % 32) > (indic_bit % 32)){
+			*(uint32_t *)indic_pos = indic;
+			indic = 0;
+			indic_pos = &compressed[compressed_pos];
+			compressed_pos += sizeof(uint32_t);
+		}
+	} while (uncompressed_pos < uncompressed_size);
+
+	if ((indic_bit % 32) > 0) {
+		for (; (indic_bit % 32) != 0; indic_bit++)
+			indic |= 0 << (32 - ((indic_bit % 32) + 1));
+
+		*(uint32_t *)indic_pos = indic;
+		compressed_pos += sizeof(uint32_t);
+	}
+
+	return compressed_pos;
+}
+
+ssize_t lzxpress_decompress(const uint8_t *input,
+			    uint32_t input_size,
+			    uint8_t *output,
+			    uint32_t max_output_size)
+{
+	uint32_t output_index, input_index;
+	uint32_t indicator, indicator_bit;
+	uint32_t length;
+	uint32_t offset;
+	uint32_t 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(uint32_t);
+			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(uint8_t);
+			output_index += sizeof(uint8_t);
+		} else {
+			length = PULL_LE_UINT16(input, input_index);
+			input_index += sizeof(uint16_t);
+			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(uint8_t);
+				} else {
+					length = input[nibble_index] / 16;
+					nibble_index = 0;
+				}
+
+				if (length == 15) {
+					length = input[input_index];
+					input_index += sizeof(uint8_t);
+					if (length == 255) {
+						length = PULL_LE_UINT16(input, input_index);
+						input_index += sizeof(uint16_t);
+						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(uint8_t);
+				length -= sizeof(uint8_t);
+			} while (length != 0);
+		}
+	} while ((output_index < max_output_size) && (input_index < (input_size)));
+
+	return output_index;
+}