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diff --git a/main/snappy/snappy-stubs-internal.h b/main/snappy/snappy-stubs-internal.h
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--- a/main/snappy/snappy-stubs-internal.h
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-// Copyright 2011 Google Inc. All Rights Reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-// * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-// * 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.
-// * Neither the name of Google Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT
-// OWNER 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.
-//
-// Various stubs for the open-source version of Snappy.
-
-#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
-#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <string>
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-
-#ifdef HAVE_SYS_MMAN_H
-#include <sys/mman.h>
-#endif
-
-#include "snappy-stubs-public.h"
-
-#if defined(__x86_64__)
-
-// Enable 64-bit optimized versions of some routines.
-#define ARCH_K8 1
-
-#endif
-
-// Needed by OS X, among others.
-#ifndef MAP_ANONYMOUS
-#define MAP_ANONYMOUS MAP_ANON
-#endif
-
-// Pull in std::min, std::ostream, and the likes. This is safe because this
-// header file is never used from any public header files.
-using namespace std;
-
-// The size of an array, if known at compile-time.
-// Will give unexpected results if used on a pointer.
-// We undefine it first, since some compilers already have a definition.
-#ifdef ARRAYSIZE
-#undef ARRAYSIZE
-#endif
-#define ARRAYSIZE(a) (sizeof(a) / sizeof(*(a)))
-
-// Static prediction hints.
-#ifdef HAVE_BUILTIN_EXPECT
-#define PREDICT_FALSE(x) (__builtin_expect(x, 0))
-#define PREDICT_TRUE(x) (__builtin_expect(!!(x), 1))
-#else
-#define PREDICT_FALSE(x) x
-#define PREDICT_TRUE(x) x
-#endif
-
-// This is only used for recomputing the tag byte table used during
-// decompression; for simplicity we just remove it from the open-source
-// version (anyone who wants to regenerate it can just do the call
-// themselves within main()).
-#define DEFINE_bool(flag_name, default_value, description) \
- bool FLAGS_ ## flag_name = default_value
-#define DECLARE_bool(flag_name) \
- extern bool FLAGS_ ## flag_name
-
-namespace snappy {
-
-static const uint32 kuint32max = static_cast<uint32>(0xFFFFFFFF);
-static const int64 kint64max = static_cast<int64>(0x7FFFFFFFFFFFFFFFLL);
-
-// Potentially unaligned loads and stores.
-
-// x86 and PowerPC can simply do these loads and stores native.
-
-#if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__)
-
-#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))
-#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))
-#define UNALIGNED_LOAD64(_p) (*reinterpret_cast<const uint64 *>(_p))
-
-#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))
-#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))
-#define UNALIGNED_STORE64(_p, _val) (*reinterpret_cast<uint64 *>(_p) = (_val))
-
-// ARMv7 and newer support native unaligned accesses, but only of 16-bit
-// and 32-bit values (not 64-bit); older versions either raise a fatal signal,
-// do an unaligned read and rotate the words around a bit, or do the reads very
-// slowly (trip through kernel mode). There's no simple #define that says just
-// “ARMv7 or higher”, so we have to filter away all ARMv5 and ARMv6
-// sub-architectures.
-//
-// This is a mess, but there's not much we can do about it.
-
-#elif defined(__arm__) && \
- !defined(__ARM_ARCH_4__) && \
- !defined(__ARM_ARCH_4T__) && \
- !defined(__ARM_ARCH_5__) && \
- !defined(__ARM_ARCH_5T__) && \
- !defined(__ARM_ARCH_5TE__) && \
- !defined(__ARM_ARCH_5TEJ__) && \
- !defined(__ARM_ARCH_6__) && \
- !defined(__ARM_ARCH_6J__) && \
- !defined(__ARM_ARCH_6K__) && \
- !defined(__ARM_ARCH_6Z__) && \
- !defined(__ARM_ARCH_6ZK__) && \
- !defined(__ARM_ARCH_6T2__)
-
-#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))
-#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))
-
-#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))
-#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))
-
-// TODO(user): NEON supports unaligned 64-bit loads and stores.
-// See if that would be more efficient on platforms supporting it,
-// at least for copies.
-
-inline uint64 UNALIGNED_LOAD64(const void *p) {
- uint64 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline void UNALIGNED_STORE64(void *p, uint64 v) {
- memcpy(p, &v, sizeof v);
-}
-
-#else
-
-// These functions are provided for architectures that don't support
-// unaligned loads and stores.
-
-inline uint16 UNALIGNED_LOAD16(const void *p) {
- uint16 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline uint32 UNALIGNED_LOAD32(const void *p) {
- uint32 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline uint64 UNALIGNED_LOAD64(const void *p) {
- uint64 t;
- memcpy(&t, p, sizeof t);
- return t;
-}
-
-inline void UNALIGNED_STORE16(void *p, uint16 v) {
- memcpy(p, &v, sizeof v);
-}
-
-inline void UNALIGNED_STORE32(void *p, uint32 v) {
- memcpy(p, &v, sizeof v);
-}
-
-inline void UNALIGNED_STORE64(void *p, uint64 v) {
- memcpy(p, &v, sizeof v);
-}
-
-#endif
-
-// This can be more efficient than UNALIGNED_LOAD64 + UNALIGNED_STORE64
-// on some platforms, in particular ARM.
-inline void UnalignedCopy64(const void *src, void *dst) {
- if (sizeof(void *) == 8) {
- UNALIGNED_STORE64(dst, UNALIGNED_LOAD64(src));
- } else {
- const char *src_char = reinterpret_cast<const char *>(src);
- char *dst_char = reinterpret_cast<char *>(dst);
-
- UNALIGNED_STORE32(dst_char, UNALIGNED_LOAD32(src_char));
- UNALIGNED_STORE32(dst_char + 4, UNALIGNED_LOAD32(src_char + 4));
- }
-}
-
-// The following guarantees declaration of the byte swap functions.
-#ifdef WORDS_BIGENDIAN
-
-#ifdef HAVE_SYS_BYTEORDER_H
-#include <sys/byteorder.h>
-#endif
-
-#ifdef HAVE_SYS_ENDIAN_H
-#include <sys/endian.h>
-#endif
-
-#ifdef _MSC_VER
-#include <stdlib.h>
-#define bswap_16(x) _byteswap_ushort(x)
-#define bswap_32(x) _byteswap_ulong(x)
-#define bswap_64(x) _byteswap_uint64(x)
-
-#elif defined(__APPLE__)
-// Mac OS X / Darwin features
-#include <libkern/OSByteOrder.h>
-#define bswap_16(x) OSSwapInt16(x)
-#define bswap_32(x) OSSwapInt32(x)
-#define bswap_64(x) OSSwapInt64(x)
-
-#elif defined(HAVE_BYTESWAP_H)
-#include <byteswap.h>
-
-#elif defined(bswap32)
-// FreeBSD defines bswap{16,32,64} in <sys/endian.h> (already #included).
-#define bswap_16(x) bswap16(x)
-#define bswap_32(x) bswap32(x)
-#define bswap_64(x) bswap64(x)
-
-#elif defined(BSWAP_64)
-// Solaris 10 defines BSWAP_{16,32,64} in <sys/byteorder.h> (already #included).
-#define bswap_16(x) BSWAP_16(x)
-#define bswap_32(x) BSWAP_32(x)
-#define bswap_64(x) BSWAP_64(x)
-
-#else
-
-inline uint16 bswap_16(uint16 x) {
- return (x << 8) | (x >> 8);
-}
-
-inline uint32 bswap_32(uint32 x) {
- x = ((x & 0xff00ff00UL) >> 8) | ((x & 0x00ff00ffUL) << 8);
- return (x >> 16) | (x << 16);
-}
-
-inline uint64 bswap_64(uint64 x) {
- x = ((x & 0xff00ff00ff00ff00ULL) >> 8) | ((x & 0x00ff00ff00ff00ffULL) << 8);
- x = ((x & 0xffff0000ffff0000ULL) >> 16) | ((x & 0x0000ffff0000ffffULL) << 16);
- return (x >> 32) | (x << 32);
-}
-
-#endif
-
-#endif // WORDS_BIGENDIAN
-
-// Convert to little-endian storage, opposite of network format.
-// Convert x from host to little endian: x = LittleEndian.FromHost(x);
-// convert x from little endian to host: x = LittleEndian.ToHost(x);
-//
-// Store values into unaligned memory converting to little endian order:
-// LittleEndian.Store16(p, x);
-//
-// Load unaligned values stored in little endian converting to host order:
-// x = LittleEndian.Load16(p);
-class LittleEndian {
- public:
- // Conversion functions.
-#ifdef WORDS_BIGENDIAN
-
- static uint16 FromHost16(uint16 x) { return bswap_16(x); }
- static uint16 ToHost16(uint16 x) { return bswap_16(x); }
-
- static uint32 FromHost32(uint32 x) { return bswap_32(x); }
- static uint32 ToHost32(uint32 x) { return bswap_32(x); }
-
- static bool IsLittleEndian() { return false; }
-
-#else // !defined(WORDS_BIGENDIAN)
-
- static uint16 FromHost16(uint16 x) { return x; }
- static uint16 ToHost16(uint16 x) { return x; }
-
- static uint32 FromHost32(uint32 x) { return x; }
- static uint32 ToHost32(uint32 x) { return x; }
-
- static bool IsLittleEndian() { return true; }
-
-#endif // !defined(WORDS_BIGENDIAN)
-
- // Functions to do unaligned loads and stores in little-endian order.
- static uint16 Load16(const void *p) {
- return ToHost16(UNALIGNED_LOAD16(p));
- }
-
- static void Store16(void *p, uint16 v) {
- UNALIGNED_STORE16(p, FromHost16(v));
- }
-
- static uint32 Load32(const void *p) {
- return ToHost32(UNALIGNED_LOAD32(p));
- }
-
- static void Store32(void *p, uint32 v) {
- UNALIGNED_STORE32(p, FromHost32(v));
- }
-};
-
-// Some bit-manipulation functions.
-class Bits {
- public:
- // Return floor(log2(n)) for positive integer n. Returns -1 iff n == 0.
- static int Log2Floor(uint32 n);
-
- // Return the first set least / most significant bit, 0-indexed. Returns an
- // undefined value if n == 0. FindLSBSetNonZero() is similar to ffs() except
- // that it's 0-indexed.
- static int FindLSBSetNonZero(uint32 n);
- static int FindLSBSetNonZero64(uint64 n);
-
- private:
- DISALLOW_COPY_AND_ASSIGN(Bits);
-};
-
-#ifdef HAVE_BUILTIN_CTZ
-
-inline int Bits::Log2Floor(uint32 n) {
- return n == 0 ? -1 : 31 ^ __builtin_clz(n);
-}
-
-inline int Bits::FindLSBSetNonZero(uint32 n) {
- return __builtin_ctz(n);
-}
-
-inline int Bits::FindLSBSetNonZero64(uint64 n) {
- return __builtin_ctzll(n);
-}
-
-#else // Portable versions.
-
-inline int Bits::Log2Floor(uint32 n) {
- if (n == 0)
- return -1;
- int log = 0;
- uint32 value = n;
- for (int i = 4; i >= 0; --i) {
- int shift = (1 << i);
- uint32 x = value >> shift;
- if (x != 0) {
- value = x;
- log += shift;
- }
- }
- assert(value == 1);
- return log;
-}
-
-inline int Bits::FindLSBSetNonZero(uint32 n) {
- int rc = 31;
- for (int i = 4, shift = 1 << 4; i >= 0; --i) {
- const uint32 x = n << shift;
- if (x != 0) {
- n = x;
- rc -= shift;
- }
- shift >>= 1;
- }
- return rc;
-}
-
-// FindLSBSetNonZero64() is defined in terms of FindLSBSetNonZero().
-inline int Bits::FindLSBSetNonZero64(uint64 n) {
- const uint32 bottombits = static_cast<uint32>(n);
- if (bottombits == 0) {
- // Bottom bits are zero, so scan in top bits
- return 32 + FindLSBSetNonZero(static_cast<uint32>(n >> 32));
- } else {
- return FindLSBSetNonZero(bottombits);
- }
-}
-
-#endif // End portable versions.
-
-// Variable-length integer encoding.
-class Varint {
- public:
- // Maximum lengths of varint encoding of uint32.
- static const int kMax32 = 5;
-
- // Attempts to parse a varint32 from a prefix of the bytes in [ptr,limit-1].
- // Never reads a character at or beyond limit. If a valid/terminated varint32
- // was found in the range, stores it in *OUTPUT and returns a pointer just
- // past the last byte of the varint32. Else returns NULL. On success,
- // "result <= limit".
- static const char* Parse32WithLimit(const char* ptr, const char* limit,
- uint32* OUTPUT);
-
- // REQUIRES "ptr" points to a buffer of length sufficient to hold "v".
- // EFFECTS Encodes "v" into "ptr" and returns a pointer to the
- // byte just past the last encoded byte.
- static char* Encode32(char* ptr, uint32 v);
-
- // EFFECTS Appends the varint representation of "value" to "*s".
- static void Append32(string* s, uint32 value);
-};
-
-inline const char* Varint::Parse32WithLimit(const char* p,
- const char* l,
- uint32* OUTPUT) {
- const unsigned char* ptr = reinterpret_cast<const unsigned char*>(p);
- const unsigned char* limit = reinterpret_cast<const unsigned char*>(l);
- uint32 b, result;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result = b & 127; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 7; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 14; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 21; if (b < 128) goto done;
- if (ptr >= limit) return NULL;
- b = *(ptr++); result |= (b & 127) << 28; if (b < 16) goto done;
- return NULL; // Value is too long to be a varint32
- done:
- *OUTPUT = result;
- return reinterpret_cast<const char*>(ptr);
-}
-
-inline char* Varint::Encode32(char* sptr, uint32 v) {
- // Operate on characters as unsigneds
- unsigned char* ptr = reinterpret_cast<unsigned char*>(sptr);
- static const int B = 128;
- if (v < (1<<7)) {
- *(ptr++) = v;
- } else if (v < (1<<14)) {
- *(ptr++) = v | B;
- *(ptr++) = v>>7;
- } else if (v < (1<<21)) {
- *(ptr++) = v | B;
- *(ptr++) = (v>>7) | B;
- *(ptr++) = v>>14;
- } else if (v < (1<<28)) {
- *(ptr++) = v | B;
- *(ptr++) = (v>>7) | B;
- *(ptr++) = (v>>14) | B;
- *(ptr++) = v>>21;
- } else {
- *(ptr++) = v | B;
- *(ptr++) = (v>>7) | B;
- *(ptr++) = (v>>14) | B;
- *(ptr++) = (v>>21) | B;
- *(ptr++) = v>>28;
- }
- return reinterpret_cast<char*>(ptr);
-}
-
-// If you know the internal layout of the std::string in use, you can
-// replace this function with one that resizes the string without
-// filling the new space with zeros (if applicable) --
-// it will be non-portable but faster.
-inline void STLStringResizeUninitialized(string* s, size_t new_size) {
- s->resize(new_size);
-}
-
-// Return a mutable char* pointing to a string's internal buffer,
-// which may not be null-terminated. Writing through this pointer will
-// modify the string.
-//
-// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
-// next call to a string method that invalidates iterators.
-//
-// As of 2006-04, there is no standard-blessed way of getting a
-// mutable reference to a string's internal buffer. However, issue 530
-// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-defects.html#530)
-// proposes this as the method. It will officially be part of the standard
-// for C++0x. This should already work on all current implementations.
-inline char* string_as_array(string* str) {
- return str->empty() ? NULL : &*str->begin();
-}
-
-} // namespace snappy
-
-#endif // UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
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