New feature: "Large Window Brotli" (google#640)

* New feature: "Large Window Brotli"

By setting special encoder/decoder flag it is now possible to extend
LZ-window up to 30 bits; though produced stream will not be RFC7932
compliant.

Added new dictionary generator - "DSH". It combines speed of "Sieve"
and quality of "DM". Plus utilities to prepare train corpora
(remove unique strings).

Improved compression ratio: now two sub-blocks could be stitched:
the last copy command could be extended to span the next sub-block.

Fixed compression ineffectiveness caused by floating numbers rounding and
wrong cost heuristic.

Other C changes:
 - combined / moved `context.h` to `common`
 - moved transforms to `common`
 - unified some aspects of code formatting
 - added an abstraction for encoder (static) dictionary
 - moved default allocator/deallocator functions to `common`

brotli CLI:
 - window size is auto-adjusted if not specified explicitly

Java:
 - added "eager" decoding both to JNI wrapper and pure decoder
 - huge speed-up of `DictionaryData` initialization

* Add dictionaryless compressed dictionary

* Fix `sources.lst`

* Fix `sources.lst` and add a note that `libtool` is also required.

* Update setup.py

* Fix `EagerStreamTest`

* Fix BUILD file

* Add missing `libdivsufsort` dependency

* Fix "unused parameter" warning.

Author: eustas

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "research/esaxx"]
 	path = research/esaxx
 	url = https://github.com/hillbig/esaxx
+[submodule "research/libdivsufsort"]
+	path = research/libdivsufsort
+	url = https://github.com/y-256/libdivsufsort.git

WORKSPACE

@@ -82,6 +82,12 @@ filegroup(
 )""",
 )
 
+new_local_repository(
+    name = "divsufsort",
+    build_file = "//research:BUILD.libdivsufsort",
+    path = "research/libdivsufsort",
+)
+
 load("@io_bazel_rules_closure//closure:defs.bzl", "closure_repositories")
 closure_repositories()
 

bootstrap

@@ -7,6 +7,8 @@ sed --version >/dev/null 2>&1 || { echo >&2 "'sed' $REQUIRED"; exit 1; }
 fi
 autoreconf --version >/dev/null 2>&1 || { echo >&2 "'autoconf' $REQUIRED"; exit 1; }
 
+# If libtool is not installed -> "error: Libtool library used but 'LIBTOOL' is undefined"
+
 mkdir m4 2>/dev/null
 
 BROTLI_ABI_HEX=`sed -n 's/#define BROTLI_ABI_VERSION 0x//p' c/common/version.h`

c/common/constants.h

@@ -28,18 +28,25 @@
 /* "code length of 8 is repeated" */
 #define BROTLI_INITIAL_REPEATED_CODE_LENGTH 8
 
+/* "Large Window Brotli" */
+#define BROTLI_LARGE_MAX_DISTANCE_BITS 62U
+#define BROTLI_LARGE_MIN_WBITS 10
+#define BROTLI_LARGE_MAX_WBITS 30
+
 /* Specification: 4. Encoding of distances */
 #define BROTLI_NUM_DISTANCE_SHORT_CODES 16
 #define BROTLI_MAX_NPOSTFIX 3
 #define BROTLI_MAX_NDIRECT 120
 #define BROTLI_MAX_DISTANCE_BITS 24U
-/* BROTLI_NUM_DISTANCE_SYMBOLS == 520 */
-#define BROTLI_NUM_DISTANCE_SYMBOLS (BROTLI_NUM_DISTANCE_SHORT_CODES + \
-                                     BROTLI_MAX_NDIRECT +              \
-                                     (BROTLI_MAX_DISTANCE_BITS <<      \
-                                      (BROTLI_MAX_NPOSTFIX + 1)))
-/* Distance that is guaranteed to be representable in any stream. */
+#define BROTLI_DISTANCE_ALPHABET_SIZE(NDIRECT, NPOSTFIX, MAXNBITS) ( \
+    BROTLI_NUM_DISTANCE_SHORT_CODES + (NDIRECT) +                    \
+    ((MAXNBITS) << ((NPOSTFIX) + 1)))
+/* BROTLI_NUM_DISTANCE_SYMBOLS == 1128 */
+#define BROTLI_NUM_DISTANCE_SYMBOLS \
+    BROTLI_DISTANCE_ALPHABET_SIZE(  \
+        BROTLI_MAX_NDIRECT, BROTLI_MAX_NPOSTFIX, BROTLI_LARGE_MAX_DISTANCE_BITS)
 #define BROTLI_MAX_DISTANCE 0x3FFFFFC
+#define BROTLI_MAX_ALLOWED_DISTANCE 0x7FFFFFFC
 
 /* 7.1. Context modes and context ID lookup for literals */
 /* "context IDs for literals are in the range of 0..63" */

c/dec/context.h c/common/context.h

@@ -10,6 +10,7 @@
 #define BROTLI_COMMON_PLATFORM_H_
 
 #include <string.h>  /* memcpy */
+#include <stdlib.h>  /* malloc, free */
 
 #include <brotli/port.h>
 #include <brotli/types.h>
@@ -204,7 +205,7 @@ static BROTLI_INLINE uint64_t BrotliUnalignedRead64(const void* p) {
 static BROTLI_INLINE void BrotliUnalignedWrite64(void* p, uint64_t v) {
   memcpy(p, &v, sizeof v);
 }
-#else /* BROTLI_ALIGNED_READ */
+#else  /* BROTLI_ALIGNED_READ */
 /* Unaligned memory access is allowed: just cast pointer to requested type. */
 static BROTLI_INLINE uint16_t BrotliUnalignedRead16(const void* p) {
   return *(const uint16_t*)p;
@@ -218,7 +219,7 @@ static BROTLI_INLINE uint64_t BrotliUnalignedRead64(const void* p) {
 static BROTLI_INLINE void BrotliUnalignedWrite64(void* p, uint64_t v) {
   *(uint64_t*)p = v;
 }
-#endif /* BROTLI_ALIGNED_READ */
+#endif  /* BROTLI_ALIGNED_READ */
 
 #if BROTLI_LITTLE_ENDIAN
 /* Straight endianness. Just read / write values. */
@@ -390,6 +391,18 @@ BROTLI_MIN_MAX(size_t) BROTLI_MIN_MAX(uint32_t) BROTLI_MIN_MAX(uint8_t)
   (A)[(J)] = __brotli_swap_tmp;   \
 }
 
+/* Default brotli_alloc_func */
+static void* BrotliDefaultAllocFunc(void* opaque, size_t size) {
+  BROTLI_UNUSED(opaque);
+  return malloc(size);
+}
+
+/* Default brotli_free_func */
+static void BrotliDefaultFreeFunc(void* opaque, void* address) {
+  BROTLI_UNUSED(opaque);
+  free(address);
+}
+
 BROTLI_UNUSED_FUNCTION void BrotliSuppressUnusedFunctions(void) {
   BROTLI_UNUSED(BrotliSuppressUnusedFunctions);
   BROTLI_UNUSED(BrotliUnalignedRead16);
@@ -413,6 +426,11 @@ BROTLI_UNUSED_FUNCTION void BrotliSuppressUnusedFunctions(void) {
   BROTLI_UNUSED(brotli_max_uint32_t);
   BROTLI_UNUSED(brotli_min_uint8_t);
   BROTLI_UNUSED(brotli_max_uint8_t);
+  BROTLI_UNUSED(BrotliDefaultAllocFunc);
+  BROTLI_UNUSED(BrotliDefaultFreeFunc);
+#if defined(BROTLI_DEBUG) || defined(BROTLI_ENABLE_LOG)
+  BROTLI_UNUSED(BrotliDump);
+#endif
 }
 
 #endif  /* BROTLI_COMMON_PLATFORM_H_ */

c/common/dictionary.bin.br

@@ -0,0 +1,236 @@
+/* Copyright 2013 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+#include "./platform.h"
+#include "./transform.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+/* RFC 7932 transforms string data */
+static const char kPrefixSuffix[217] =
+      "\1 \2, \10 of the \4 of \2s \1.\5 and \4 "
+/* 0x  _0 _2  __5        _E    _3  _6 _8     _E */
+      "in \1\"\4 to \2\">\1\n\2. \1]\5 for \3 a \6 "
+/* 2x     _3_ _5    _A_  _D_ _F  _2 _4     _A   _E */
+      "that \1\'\6 with \6 from \4 by \1(\6. T"
+/* 4x       _5_ _7      _E      _5    _A _C */
+      "he \4 on \4 as \4 is \4ing \2\n\t\1:\3ed "
+/* 6x     _3    _8    _D    _2    _7_ _ _A _C */
+      "\2=\"\4 at \3ly \1,\2=\'\5.com/\7. This \5"
+/* 8x  _0 _ _3    _8   _C _E _ _1     _7       _F */
+      " not \3er \3al \4ful \4ive \5less \4es"
+/* Ax       _5   _9   _D    _2    _7     _D */
+      "t \4ize \2\xc2\xa0\4ous \5 the \2e \0";
+/* Cx    _2    _7___ ___ _A    _F     _5  _8 */
+
+static const uint16_t kPrefixSuffixMap[50] = {
+  0x00, 0x02, 0x05, 0x0E, 0x13, 0x16, 0x18, 0x1E, 0x23, 0x25,
+  0x2A, 0x2D, 0x2F, 0x32, 0x34, 0x3A, 0x3E, 0x45, 0x47, 0x4E,
+  0x55, 0x5A, 0x5C, 0x63, 0x68, 0x6D, 0x72, 0x77, 0x7A, 0x7C,
+  0x80, 0x83, 0x88, 0x8C, 0x8E, 0x91, 0x97, 0x9F, 0xA5, 0xA9,
+  0xAD, 0xB2, 0xB7, 0xBD, 0xC2, 0xC7, 0xCA, 0xCF, 0xD5, 0xD8
+};
+
+/* RFC 7932 transforms */
+static const uint8_t kTransformsData[] = {
+  49, BROTLI_TRANSFORM_IDENTITY, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 0,
+   0, BROTLI_TRANSFORM_IDENTITY, 0,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_1, 49,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 0,
+  49, BROTLI_TRANSFORM_IDENTITY, 47,
+   0, BROTLI_TRANSFORM_IDENTITY, 49,
+   4, BROTLI_TRANSFORM_IDENTITY, 0,
+  49, BROTLI_TRANSFORM_IDENTITY, 3,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 6,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_2, 49,
+  49, BROTLI_TRANSFORM_OMIT_LAST_1, 49,
+   1, BROTLI_TRANSFORM_IDENTITY, 0,
+  49, BROTLI_TRANSFORM_IDENTITY, 1,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 0,
+  49, BROTLI_TRANSFORM_IDENTITY, 7,
+  49, BROTLI_TRANSFORM_IDENTITY, 9,
+  48, BROTLI_TRANSFORM_IDENTITY, 0,
+  49, BROTLI_TRANSFORM_IDENTITY, 8,
+  49, BROTLI_TRANSFORM_IDENTITY, 5,
+  49, BROTLI_TRANSFORM_IDENTITY, 10,
+  49, BROTLI_TRANSFORM_IDENTITY, 11,
+  49, BROTLI_TRANSFORM_OMIT_LAST_3, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 13,
+  49, BROTLI_TRANSFORM_IDENTITY, 14,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_3, 49,
+  49, BROTLI_TRANSFORM_OMIT_LAST_2, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 15,
+  49, BROTLI_TRANSFORM_IDENTITY, 16,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 12,
+   5, BROTLI_TRANSFORM_IDENTITY, 49,
+   0, BROTLI_TRANSFORM_IDENTITY, 1,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_4, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 18,
+  49, BROTLI_TRANSFORM_IDENTITY, 17,
+  49, BROTLI_TRANSFORM_IDENTITY, 19,
+  49, BROTLI_TRANSFORM_IDENTITY, 20,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_5, 49,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_6, 49,
+  47, BROTLI_TRANSFORM_IDENTITY, 49,
+  49, BROTLI_TRANSFORM_OMIT_LAST_4, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 22,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 23,
+  49, BROTLI_TRANSFORM_IDENTITY, 24,
+  49, BROTLI_TRANSFORM_IDENTITY, 25,
+  49, BROTLI_TRANSFORM_OMIT_LAST_7, 49,
+  49, BROTLI_TRANSFORM_OMIT_LAST_1, 26,
+  49, BROTLI_TRANSFORM_IDENTITY, 27,
+  49, BROTLI_TRANSFORM_IDENTITY, 28,
+   0, BROTLI_TRANSFORM_IDENTITY, 12,
+  49, BROTLI_TRANSFORM_IDENTITY, 29,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_9, 49,
+  49, BROTLI_TRANSFORM_OMIT_FIRST_7, 49,
+  49, BROTLI_TRANSFORM_OMIT_LAST_6, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 21,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 1,
+  49, BROTLI_TRANSFORM_OMIT_LAST_8, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 31,
+  49, BROTLI_TRANSFORM_IDENTITY, 32,
+  47, BROTLI_TRANSFORM_IDENTITY, 3,
+  49, BROTLI_TRANSFORM_OMIT_LAST_5, 49,
+  49, BROTLI_TRANSFORM_OMIT_LAST_9, 49,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 1,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 8,
+   5, BROTLI_TRANSFORM_IDENTITY, 21,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 0,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 10,
+  49, BROTLI_TRANSFORM_IDENTITY, 30,
+   0, BROTLI_TRANSFORM_IDENTITY, 5,
+  35, BROTLI_TRANSFORM_IDENTITY, 49,
+  47, BROTLI_TRANSFORM_IDENTITY, 2,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 17,
+  49, BROTLI_TRANSFORM_IDENTITY, 36,
+  49, BROTLI_TRANSFORM_IDENTITY, 33,
+   5, BROTLI_TRANSFORM_IDENTITY, 0,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 21,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 5,
+  49, BROTLI_TRANSFORM_IDENTITY, 37,
+   0, BROTLI_TRANSFORM_IDENTITY, 30,
+  49, BROTLI_TRANSFORM_IDENTITY, 38,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 0,
+  49, BROTLI_TRANSFORM_IDENTITY, 39,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 49,
+  49, BROTLI_TRANSFORM_IDENTITY, 34,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 8,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 12,
+   0, BROTLI_TRANSFORM_IDENTITY, 21,
+  49, BROTLI_TRANSFORM_IDENTITY, 40,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 12,
+  49, BROTLI_TRANSFORM_IDENTITY, 41,
+  49, BROTLI_TRANSFORM_IDENTITY, 42,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 17,
+  49, BROTLI_TRANSFORM_IDENTITY, 43,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 5,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 10,
+   0, BROTLI_TRANSFORM_IDENTITY, 34,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 33,
+  49, BROTLI_TRANSFORM_IDENTITY, 44,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 5,
+  45, BROTLI_TRANSFORM_IDENTITY, 49,
+   0, BROTLI_TRANSFORM_IDENTITY, 33,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 30,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 30,
+  49, BROTLI_TRANSFORM_IDENTITY, 46,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 1,
+  49, BROTLI_TRANSFORM_UPPERCASE_FIRST, 34,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 33,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 30,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 1,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 33,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 21,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 12,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 5,
+  49, BROTLI_TRANSFORM_UPPERCASE_ALL, 34,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 12,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 30,
+   0, BROTLI_TRANSFORM_UPPERCASE_ALL, 34,
+   0, BROTLI_TRANSFORM_UPPERCASE_FIRST, 34,
+};
+
+static BrotliTransforms kBrotliTransforms = {
+  sizeof(kPrefixSuffix),
+  (const uint8_t*)kPrefixSuffix,
+  kPrefixSuffixMap,
+  sizeof(kTransformsData) / (3 * sizeof(kTransformsData[0])),
+  kTransformsData,
+  {0, 12, 27, 23, 42, 63, 56, 48, 59, 64}
+};
+
+const BrotliTransforms* BrotliGetTransforms(void) {
+  return &kBrotliTransforms;
+}
+
+static int ToUpperCase(uint8_t* p) {
+  if (p[0] < 0xC0) {
+    if (p[0] >= 'a' && p[0] <= 'z') {
+      p[0] ^= 32;
+    }
+    return 1;
+  }
+  /* An overly simplified uppercasing model for UTF-8. */
+  if (p[0] < 0xE0) {
+    p[1] ^= 32;
+    return 2;
+  }
+  /* An arbitrary transform for three byte characters. */
+  p[2] ^= 5;
+  return 3;
+}
+
+int BrotliTransformDictionaryWord(uint8_t* dst, const uint8_t* word, int len,
+    const BrotliTransforms* BROTLI_RESTRICT transforms, int transfom_idx) {
+  int idx = 0;
+  const uint8_t* prefix = BROTLI_TRANSFORM_PREFIX(transforms, transfom_idx);
+  uint8_t type = BROTLI_TRANSFORM_TYPE(transforms, transfom_idx);
+  const uint8_t* suffix = BROTLI_TRANSFORM_SUFFIX(transforms, transfom_idx);
+  {
+    int prefix_len = *prefix++;
+    while (prefix_len--) { dst[idx++] = *prefix++; }
+  }
+  {
+    const int t = type;
+    int i = 0;
+    if (t <= BROTLI_TRANSFORM_OMIT_LAST_9) {
+      len -= t;
+    } else if (t >= BROTLI_TRANSFORM_OMIT_FIRST_1
+        && t <= BROTLI_TRANSFORM_OMIT_FIRST_9) {
+      int skip = t - (BROTLI_TRANSFORM_OMIT_FIRST_1 - 1);
+      word += skip;
+      len -= skip;
+    }
+    while (i < len) { dst[idx++] = word[i++]; }
+    if (t == BROTLI_TRANSFORM_UPPERCASE_FIRST) {
+      ToUpperCase(&dst[idx - len]);
+    } else if (t == BROTLI_TRANSFORM_UPPERCASE_ALL) {
+      uint8_t* uppercase = &dst[idx - len];
+      while (len > 0) {
+        int step = ToUpperCase(uppercase);
+        uppercase += step;
+        len -= step;
+      }
+    }
+  }
+  {
+    int suffix_len = *suffix++;
+    while (suffix_len--) { dst[idx++] = *suffix++; }
+    return idx;
+  }
+}
+
+#if defined(__cplusplus) || defined(c_plusplus)
+}  /* extern "C" */
+#endif