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From j..@apache.org
Subject git commit: Update snappy to 1.0.5
Date Sat, 12 Jan 2013 18:18:40 GMT
Updated Branches:
  refs/heads/1600-update-snappy [created] 7cf76b8ab


Update snappy to 1.0.5


Project: http://git-wip-us.apache.org/repos/asf/couchdb/repo
Commit: http://git-wip-us.apache.org/repos/asf/couchdb/commit/7cf76b8a
Tree: http://git-wip-us.apache.org/repos/asf/couchdb/tree/7cf76b8a
Diff: http://git-wip-us.apache.org/repos/asf/couchdb/diff/7cf76b8a

Branch: refs/heads/1600-update-snappy
Commit: 7cf76b8ab9be8b12facf4a812ef1afa406687015
Parents: b9af7ea
Author: Jan Lehnardt <jan@apache.org>
Authored: Tue Nov 13 13:01:42 2012 +0100
Committer: Jan Lehnardt <jan@apache.org>
Committed: Sat Jan 12 19:18:22 2013 +0100

----------------------------------------------------------------------
 src/snappy/Makefile.am                           |    4 +-
 src/snappy/google-snappy/config.h.in             |   71 +++---
 src/snappy/google-snappy/snappy-sinksource.cc    |    1 -
 src/snappy/google-snappy/snappy-sinksource.h     |    1 +
 src/snappy/google-snappy/snappy-stubs-internal.h |  104 ++++++++-
 src/snappy/google-snappy/snappy.cc               |  212 ++++++++++++-----
 src/snappy/google-snappy/snappy.h                |    4 +-
 src/snappy/snappy.app.in                         |    2 +-
 8 files changed, 289 insertions(+), 110 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/Makefile.am
----------------------------------------------------------------------
diff --git a/src/snappy/Makefile.am b/src/snappy/Makefile.am
index 23dbf14..ff75f07 100644
--- a/src/snappy/Makefile.am
+++ b/src/snappy/Makefile.am
@@ -10,8 +10,8 @@
 ## License for the specific language governing permissions and limitations under
 ## the License.
 
-snappyebindir = $(localerlanglibdir)/snappy-1.0.3/ebin
-snappyprivdir = $(localerlanglibdir)/snappy-1.0.3/priv
+snappyebindir = $(localerlanglibdir)/snappy-1.0.5/ebin
+snappyprivdir = $(localerlanglibdir)/snappy-1.0.5/priv
 
 snappy_cxx_srcs = \
 	snappy_nif.cc \

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/google-snappy/config.h.in
----------------------------------------------------------------------
diff --git a/src/snappy/google-snappy/config.h.in b/src/snappy/google-snappy/config.h.in
index 52dad34..28f57c2 100644
--- a/src/snappy/google-snappy/config.h.in
+++ b/src/snappy/google-snappy/config.h.in
@@ -1,4 +1,4 @@
-/* src/snappy/google-snappy/config.h.in.  Generated from configure.ac by autoheader.  */
+/* config.h.in.  Generated from configure.ac by autoheader.  */
 
 /* Define if building universal (internal helper macro) */
 #undef AC_APPLE_UNIVERSAL_BUILD
@@ -9,15 +9,36 @@
 /* Define to 1 if the compiler supports __builtin_expect. */
 #undef HAVE_BUILTIN_EXPECT
 
-/* "Provide HTTP support to couchjs" */
-#undef HAVE_CURL
+/* Define to 1 if you have the <byteswap.h> header file. */
+#undef HAVE_BYTESWAP_H
 
 /* Define to 1 if you have the <dlfcn.h> header file. */
 #undef HAVE_DLFCN_H
 
+/* Use the gflags package for command-line parsing. */
+#undef HAVE_GFLAGS
+
+/* Defined when Google Test is available. */
+#undef HAVE_GTEST
+
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
+/* Define to 1 if you have the `fastlz' library (-lfastlz). */
+#undef HAVE_LIBFASTLZ
+
+/* Define to 1 if you have the `lzf' library (-llzf). */
+#undef HAVE_LIBLZF
+
+/* Define to 1 if you have the `lzo2' library (-llzo2). */
+#undef HAVE_LIBLZO2
+
+/* Define to 1 if you have the `quicklz' library (-lquicklz). */
+#undef HAVE_LIBQUICKLZ
+
+/* Define to 1 if you have the `z' library (-lz). */
+#undef HAVE_LIBZ
+
 /* Define to 1 if you have the <memory.h> header file. */
 #undef HAVE_MEMORY_H
 
@@ -36,6 +57,12 @@
 /* Define to 1 if you have the <string.h> header file. */
 #undef HAVE_STRING_H
 
+/* Define to 1 if you have the <sys/byteswap.h> header file. */
+#undef HAVE_SYS_BYTESWAP_H
+
+/* Define to 1 if you have the <sys/endian.h> header file. */
+#undef HAVE_SYS_ENDIAN_H
+
 /* Define to 1 if you have the <sys/mman.h> header file. */
 #undef HAVE_SYS_MMAN_H
 
@@ -51,6 +78,9 @@
 /* Define to 1 if you have the <unistd.h> header file. */
 #undef HAVE_UNISTD_H
 
+/* Define to 1 if you have the <windows.h> header file. */
+#undef HAVE_WINDOWS_H
+
 /* Define to the sub-directory in which libtool stores uninstalled libraries.
    */
 #undef LT_OBJDIR
@@ -79,31 +109,6 @@
 /* Define to 1 if you have the ANSI C header files. */
 #undef STDC_HEADERS
 
-/* Use new JS_SetOperationCallback */
-#undef USE_JS_SETOPCB
-
-/* Enable extensions on AIX 3, Interix.  */
-#ifndef _ALL_SOURCE
-# undef _ALL_SOURCE
-#endif
-/* Enable GNU extensions on systems that have them.  */
-#ifndef _GNU_SOURCE
-# undef _GNU_SOURCE
-#endif
-/* Enable threading extensions on Solaris.  */
-#ifndef _POSIX_PTHREAD_SEMANTICS
-# undef _POSIX_PTHREAD_SEMANTICS
-#endif
-/* Enable extensions on HP NonStop.  */
-#ifndef _TANDEM_SOURCE
-# undef _TANDEM_SOURCE
-#endif
-/* Enable general extensions on Solaris.  */
-#ifndef __EXTENSIONS__
-# undef __EXTENSIONS__
-#endif
-
-
 /* Version number of package */
 #undef VERSION
 
@@ -118,13 +123,3 @@
 #  undef WORDS_BIGENDIAN
 # endif
 #endif
-
-/* Define to 1 if on MINIX. */
-#undef _MINIX
-
-/* Define to 2 if the system does not provide POSIX.1 features except with
-   this defined. */
-#undef _POSIX_1_SOURCE
-
-/* Define to 1 if you need to in order for `stat' and other things to work. */
-#undef _POSIX_SOURCE

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/google-snappy/snappy-sinksource.cc
----------------------------------------------------------------------
diff --git a/src/snappy/google-snappy/snappy-sinksource.cc b/src/snappy/google-snappy/snappy-sinksource.cc
index 1017895..5844552 100644
--- a/src/snappy/google-snappy/snappy-sinksource.cc
+++ b/src/snappy/google-snappy/snappy-sinksource.cc
@@ -68,5 +68,4 @@ char* UncheckedByteArraySink::GetAppendBuffer(size_t len, char* scratch)
{
   return dest_;
 }
 
-
 }

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/google-snappy/snappy-sinksource.h
----------------------------------------------------------------------
diff --git a/src/snappy/google-snappy/snappy-sinksource.h b/src/snappy/google-snappy/snappy-sinksource.h
index 430baea..faabfa1 100644
--- a/src/snappy/google-snappy/snappy-sinksource.h
+++ b/src/snappy/google-snappy/snappy-sinksource.h
@@ -60,6 +60,7 @@ class Sink {
   // The default implementation always returns the scratch buffer.
   virtual char* GetAppendBuffer(size_t length, char* scratch);
 
+
  private:
   // No copying
   Sink(const Sink&);

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/google-snappy/snappy-stubs-internal.h
----------------------------------------------------------------------
diff --git a/src/snappy/google-snappy/snappy-stubs-internal.h b/src/snappy/google-snappy/snappy-stubs-internal.h
index 46ee235..6033cdf 100644
--- a/src/snappy/google-snappy/snappy-stubs-internal.h
+++ b/src/snappy/google-snappy/snappy-stubs-internal.h
@@ -42,7 +42,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-#ifdef HAVE_SYS_MMAN
+#ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
 #endif
 
@@ -86,10 +86,9 @@ using namespace std;
 // 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;
+  bool FLAGS_ ## flag_name = default_value
 #define DECLARE_bool(flag_name) \
-  extern bool FLAGS_ ## flag_name;
-#define REGISTER_MODULE_INITIALIZER(name, code)
+  extern bool FLAGS_ ## flag_name
 
 namespace snappy {
 
@@ -179,6 +178,8 @@ class LogMessageVoidify {
 
 // 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))
@@ -189,6 +190,47 @@ class LogMessageVoidify {
 #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_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
@@ -226,9 +268,31 @@ inline void UNALIGNED_STORE64(void *p, uint64 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)
@@ -242,8 +306,38 @@ inline void UNALIGNED_STORE64(void *p, uint64 v) {
 #define bswap_32(x) OSSwapInt32(x)
 #define bswap_64(x) OSSwapInt64(x)
 
-#else
+#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

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/google-snappy/snappy.cc
----------------------------------------------------------------------
diff --git a/src/snappy/google-snappy/snappy.cc b/src/snappy/google-snappy/snappy.cc
index a591aba..4d4eb42 100644
--- a/src/snappy/google-snappy/snappy.cc
+++ b/src/snappy/google-snappy/snappy.cc
@@ -140,12 +140,12 @@ const int kMaxIncrementCopyOverflow = 10;
 
 static inline void IncrementalCopyFastPath(const char* src, char* op, int len) {
   while (op - src < 8) {
-    UNALIGNED_STORE64(op, UNALIGNED_LOAD64(src));
+    UnalignedCopy64(src, op);
     len -= op - src;
     op += op - src;
   }
   while (len > 0) {
-    UNALIGNED_STORE64(op, UNALIGNED_LOAD64(src));
+    UnalignedCopy64(src, op);
     src += 8;
     op += 8;
     len -= 8;
@@ -172,8 +172,8 @@ static inline char* EmitLiteral(char* op,
     //   - The output will always have 32 spare bytes (see
     //     MaxCompressedLength).
     if (allow_fast_path && len <= 16) {
-      UNALIGNED_STORE64(op, UNALIGNED_LOAD64(literal));
-      UNALIGNED_STORE64(op + 8, UNALIGNED_LOAD64(literal + 8));
+      UnalignedCopy64(literal, op);
+      UnalignedCopy64(literal + 8, op + 8);
       return op + len;
     }
   } else {
@@ -194,13 +194,13 @@ static inline char* EmitLiteral(char* op,
   return op + len;
 }
 
-static inline char* EmitCopyLessThan64(char* op, int offset, int len) {
+static inline char* EmitCopyLessThan64(char* op, size_t offset, int len) {
   DCHECK_LE(len, 64);
   DCHECK_GE(len, 4);
   DCHECK_LT(offset, 65536);
 
   if ((len < 12) && (offset < 2048)) {
-    int len_minus_4 = len - 4;
+    size_t len_minus_4 = len - 4;
     assert(len_minus_4 < 8);            // Must fit in 3 bits
     *op++ = COPY_1_BYTE_OFFSET | ((len_minus_4) << 2) | ((offset >> 8) <<
5);
     *op++ = offset & 0xff;
@@ -212,7 +212,7 @@ static inline char* EmitCopyLessThan64(char* op, int offset, int len)
{
   return op;
 }
 
-static inline char* EmitCopy(char* op, int offset, int len) {
+static inline char* EmitCopy(char* op, size_t offset, int len) {
   // Emit 64 byte copies but make sure to keep at least four bytes reserved
   while (len >= 68) {
     op = EmitCopyLessThan64(op, offset, 64);
@@ -249,7 +249,7 @@ uint16* WorkingMemory::GetHashTable(size_t input_size, int* table_size)
{
   // compression, and if the input is short, we won't need that
   // many hash table entries anyway.
   assert(kMaxHashTableSize >= 256);
-  int htsize = 256;
+  size_t htsize = 256;
   while (htsize < kMaxHashTableSize && htsize < input_size) {
     htsize <<= 1;
   }
@@ -272,16 +272,49 @@ uint16* WorkingMemory::GetHashTable(size_t input_size, int* table_size)
{
 }
 }  // end namespace internal
 
-// For 0 <= offset <= 4, GetUint32AtOffset(UNALIGNED_LOAD64(p), offset) will
+// For 0 <= offset <= 4, GetUint32AtOffset(GetEightBytesAt(p), offset) will
 // equal UNALIGNED_LOAD32(p + offset).  Motivation: On x86-64 hardware we have
 // empirically found that overlapping loads such as
 //  UNALIGNED_LOAD32(p) ... UNALIGNED_LOAD32(p+1) ... UNALIGNED_LOAD32(p+2)
 // are slower than UNALIGNED_LOAD64(p) followed by shifts and casts to uint32.
+//
+// We have different versions for 64- and 32-bit; ideally we would avoid the
+// two functions and just inline the UNALIGNED_LOAD64 call into
+// GetUint32AtOffset, but GCC (at least not as of 4.6) is seemingly not clever
+// enough to avoid loading the value multiple times then. For 64-bit, the load
+// is done when GetEightBytesAt() is called, whereas for 32-bit, the load is
+// done at GetUint32AtOffset() time.
+
+#ifdef ARCH_K8
+
+typedef uint64 EightBytesReference;
+
+static inline EightBytesReference GetEightBytesAt(const char* ptr) {
+  return UNALIGNED_LOAD64(ptr);
+}
+
 static inline uint32 GetUint32AtOffset(uint64 v, int offset) {
-  DCHECK(0 <= offset && offset <= 4) << offset;
+  DCHECK_GE(offset, 0);
+  DCHECK_LE(offset, 4);
   return v >> (LittleEndian::IsLittleEndian() ? 8 * offset : 32 - 8 * offset);
 }
 
+#else
+
+typedef const char* EightBytesReference;
+
+static inline EightBytesReference GetEightBytesAt(const char* ptr) {
+  return ptr;
+}
+
+static inline uint32 GetUint32AtOffset(const char* v, int offset) {
+  DCHECK_GE(offset, 0);
+  DCHECK_LE(offset, 4);
+  return UNALIGNED_LOAD32(v + offset);
+}
+
+#endif
+
 // Flat array compression that does not emit the "uncompressed length"
 // prefix. Compresses "input" string to the "*op" buffer.
 //
@@ -294,8 +327,8 @@ static inline uint32 GetUint32AtOffset(uint64 v, int offset) {
 // Returns an "end" pointer into "op" buffer.
 // "end - op" is the compressed size of "input".
 namespace internal {
-char* CompressFragment(const char* const input,
-                       const size_t input_size,
+char* CompressFragment(const char* input,
+                       size_t input_size,
                        char* op,
                        uint16* table,
                        const int table_size) {
@@ -304,14 +337,14 @@ char* CompressFragment(const char* const input,
   CHECK_LE(input_size, kBlockSize);
   CHECK_EQ(table_size & (table_size - 1), 0) << ": table must be power of two";
   const int shift = 32 - Bits::Log2Floor(table_size);
-  DCHECK_EQ(kuint32max >> shift, table_size - 1);
+  DCHECK_EQ(static_cast<int>(kuint32max >> shift), table_size - 1);
   const char* ip_end = input + input_size;
   const char* base_ip = ip;
   // Bytes in [next_emit, ip) will be emitted as literal bytes.  Or
   // [next_emit, ip_end) after the main loop.
   const char* next_emit = ip;
 
-  const int kInputMarginBytes = 15;
+  const size_t kInputMarginBytes = 15;
   if (PREDICT_TRUE(input_size >= kInputMarginBytes)) {
     const char* ip_limit = input + input_size - kInputMarginBytes;
 
@@ -378,7 +411,7 @@ char* CompressFragment(const char* const input,
       // though we don't yet know how big the literal will be.  We handle that
       // by proceeding to the next iteration of the main loop.  We also can exit
       // this loop via goto if we get close to exhausting the input.
-      uint64 input_bytes = 0;
+      EightBytesReference input_bytes;
       uint32 candidate_bytes = 0;
 
       do {
@@ -387,7 +420,7 @@ char* CompressFragment(const char* const input,
         const char* base = ip;
         int matched = 4 + FindMatchLength(candidate + 4, ip + 4, ip_end);
         ip += matched;
-        int offset = base - candidate;
+        size_t offset = base - candidate;
         DCHECK_EQ(0, memcmp(base, candidate, matched));
         op = EmitCopy(op, offset, matched);
         // We could immediately start working at ip now, but to improve
@@ -397,7 +430,7 @@ char* CompressFragment(const char* const input,
         if (PREDICT_FALSE(ip >= ip_limit)) {
           goto emit_remainder;
         }
-        input_bytes = UNALIGNED_LOAD64(insert_tail);
+        input_bytes = GetEightBytesAt(insert_tail);
         uint32 prev_hash = HashBytes(GetUint32AtOffset(input_bytes, 0), shift);
         table[prev_hash] = ip - base_ip - 1;
         uint32 cur_hash = HashBytes(GetUint32AtOffset(input_bytes, 1), shift);
@@ -435,12 +468,26 @@ char* CompressFragment(const char* const input,
 //   bool CheckLength() const;
 //
 //   // Called repeatedly during decompression
-//   bool Append(const char* ip, uint32 length, bool allow_fast_path);
-//   bool AppendFromSelf(uint32 offset, uint32 length);
-// };
+//   bool Append(const char* ip, size_t length);
+//   bool AppendFromSelf(uint32 offset, size_t length);
 //
-// "allow_fast_path" is a parameter that says if there is at least 16
-// readable bytes in "ip". It is currently only used by SnappyArrayWriter.
+//   // The difference between TryFastAppend and Append is that TryFastAppend
+//   // is allowed to read up to <available> bytes from the input buffer,
+//   // whereas Append is allowed to read <length>.
+//   //
+//   // Also, TryFastAppend is allowed to return false, declining the append,
+//   // without it being a fatal error -- just "return false" would be
+//   // a perfectly legal implementation of TryFastAppend. The intention
+//   // is for TryFastAppend to allow a fast path in the common case of
+//   // a small append.
+//   //
+//   // NOTE(user): TryFastAppend must always return decline (return false)
+//   // if <length> is 61 or more, as in this case the literal length is not
+//   // decoded fully. In practice, this should not be a big problem,
+//   // as it is unlikely that one would implement a fast path accepting
+//   // this much data.
+//   bool TryFastAppend(const char* ip, size_t available, size_t length);
+// };
 
 // -----------------------------------------------------------------------
 // Lookup table for decompression code.  Generated by ComputeTable() below.
@@ -587,7 +634,6 @@ static void ComputeTable() {
     CHECK_EQ(dst[i], char_table[i]);
   }
 }
-REGISTER_MODULE_INITIALIZER(snappy, ComputeTable());
 #endif /* !NDEBUG */
 
 // Helper class for decompression
@@ -655,25 +701,41 @@ class SnappyDecompressor {
   template <class Writer>
   void DecompressAllTags(Writer* writer) {
     const char* ip = ip_;
-    for ( ;; ) {
-      if (ip_limit_ - ip < 5) {
-        ip_ = ip;
-        if (!RefillTag()) return;
-        ip = ip_;
-      }
 
+    // We could have put this refill fragment only at the beginning of the loop.
+    // However, duplicating it at the end of each branch gives the compiler more
+    // scope to optimize the <ip_limit_ - ip> expression based on the local
+    // context, which overall increases speed.
+    #define MAYBE_REFILL() \
+        if (ip_limit_ - ip < 5) { \
+          ip_ = ip; \
+          if (!RefillTag()) return; \
+          ip = ip_; \
+        }
+
+    MAYBE_REFILL();
+    for ( ;; ) {
       const unsigned char c = *(reinterpret_cast<const unsigned char*>(ip++));
-      const uint32 entry = char_table[c];
-      const uint32 trailer = LittleEndian::Load32(ip) & wordmask[entry >> 11];
-      ip += entry >> 11;
-      const uint32 length = entry & 0xff;
 
       if ((c & 0x3) == LITERAL) {
-        uint32 literal_length = length + trailer;
-        uint32 avail = ip_limit_ - ip;
+        size_t literal_length = (c >> 2) + 1u;
+        if (writer->TryFastAppend(ip, ip_limit_ - ip, literal_length)) {
+          DCHECK_LT(literal_length, 61);
+          ip += literal_length;
+          MAYBE_REFILL();
+          continue;
+        }
+        if (PREDICT_FALSE(literal_length >= 61)) {
+          // Long literal.
+          const size_t literal_length_length = literal_length - 60;
+          literal_length =
+              (LittleEndian::Load32(ip) & wordmask[literal_length_length]) + 1;
+          ip += literal_length_length;
+        }
+
+        size_t avail = ip_limit_ - ip;
         while (avail < literal_length) {
-          bool allow_fast_path = (avail >= 16);
-          if (!writer->Append(ip, avail, allow_fast_path)) return;
+          if (!writer->Append(ip, avail)) return;
           literal_length -= avail;
           reader_->Skip(peeked_);
           size_t n;
@@ -683,12 +745,17 @@ class SnappyDecompressor {
           if (avail == 0) return;  // Premature end of input
           ip_limit_ = ip + avail;
         }
-        bool allow_fast_path = (avail >= 16);
-        if (!writer->Append(ip, literal_length, allow_fast_path)) {
+        if (!writer->Append(ip, literal_length)) {
           return;
         }
         ip += literal_length;
+        MAYBE_REFILL();
       } else {
+        const uint32 entry = char_table[c];
+        const uint32 trailer = LittleEndian::Load32(ip) & wordmask[entry >> 11];
+        const uint32 length = entry & 0xff;
+        ip += entry >> 11;
+
         // copy_offset/256 is encoded in bits 8..10.  By just fetching
         // those bits, we get copy_offset (since the bit-field starts at
         // bit 8).
@@ -696,8 +763,11 @@ class SnappyDecompressor {
         if (!writer->AppendFromSelf(copy_offset + trailer, length)) {
           return;
         }
+        MAYBE_REFILL();
       }
     }
+
+#undef MAYBE_REFILL
   }
 };
 
@@ -768,6 +838,15 @@ static bool InternalUncompress(Source* r,
   SnappyDecompressor decompressor(r);
   uint32 uncompressed_len = 0;
   if (!decompressor.ReadUncompressedLength(&uncompressed_len)) return false;
+  return InternalUncompressAllTags(
+      &decompressor, writer, uncompressed_len, max_len);
+}
+
+template <typename Writer>
+static bool InternalUncompressAllTags(SnappyDecompressor* decompressor,
+                                      Writer* writer,
+                                      uint32 uncompressed_len,
+                                      uint32 max_len) {
   // Protect against possible DoS attack
   if (static_cast<uint64>(uncompressed_len) > max_len) {
     return false;
@@ -776,8 +855,8 @@ static bool InternalUncompress(Source* r,
   writer->SetExpectedLength(uncompressed_len);
 
   // Process the entire input
-  decompressor.DecompressAllTags(writer);
-  return (decompressor.eof() && writer->CheckLength());
+  decompressor->DecompressAllTags(writer);
+  return (decompressor->eof() && writer->CheckLength());
 }
 
 bool GetUncompressedLength(Source* source, uint32* result) {
@@ -787,7 +866,7 @@ bool GetUncompressedLength(Source* source, uint32* result) {
 
 size_t Compress(Source* reader, Sink* writer) {
   size_t written = 0;
-  int N = reader->Available();
+  size_t N = reader->Available();
   char ulength[Varint::kMax32];
   char* p = Varint::Encode32(ulength, N);
   writer->Append(ulength, p-ulength);
@@ -802,10 +881,10 @@ size_t Compress(Source* reader, Sink* writer) {
     size_t fragment_size;
     const char* fragment = reader->Peek(&fragment_size);
     DCHECK_NE(fragment_size, 0) << ": premature end of input";
-    const int num_to_read = min(N, kBlockSize);
+    const size_t num_to_read = min(N, kBlockSize);
     size_t bytes_read = fragment_size;
 
-    int pending_advance = 0;
+    size_t pending_advance = 0;
     if (bytes_read >= num_to_read) {
       // Buffer returned by reader is large enough
       pending_advance = num_to_read;
@@ -893,34 +972,42 @@ class SnappyArrayWriter {
     return op_ == op_limit_;
   }
 
-  inline bool Append(const char* ip, uint32 len, bool allow_fast_path) {
+  inline bool Append(const char* ip, size_t len) {
     char* op = op_;
-    const int space_left = op_limit_ - op;
-    if (allow_fast_path && len <= 16 && space_left >= 16) {
-      // Fast path, used for the majority (about 90%) of dynamic invocations.
-      UNALIGNED_STORE64(op, UNALIGNED_LOAD64(ip));
-      UNALIGNED_STORE64(op + 8, UNALIGNED_LOAD64(ip + 8));
-    } else {
-      if (space_left < len) {
-        return false;
-      }
-      memcpy(op, ip, len);
+    const size_t space_left = op_limit_ - op;
+    if (space_left < len) {
+      return false;
     }
+    memcpy(op, ip, len);
     op_ = op + len;
     return true;
   }
 
-  inline bool AppendFromSelf(uint32 offset, uint32 len) {
+  inline bool TryFastAppend(const char* ip, size_t available, size_t len) {
     char* op = op_;
-    const int space_left = op_limit_ - op;
+    const size_t space_left = op_limit_ - op;
+    if (len <= 16 && available >= 16 && space_left >= 16) {
+      // Fast path, used for the majority (about 95%) of invocations.
+      UnalignedCopy64(ip, op);
+      UnalignedCopy64(ip + 8, op + 8);
+      op_ = op + len;
+      return true;
+    } else {
+      return false;
+    }
+  }
+
+  inline bool AppendFromSelf(size_t offset, size_t len) {
+    char* op = op_;
+    const size_t space_left = op_limit_ - op;
 
     if (op - base_ <= offset - 1u) {  // -1u catches offset==0
       return false;
     }
     if (len <= 16 && offset >= 8 && space_left >= 16) {
       // Fast path, used for the majority (70-80%) of dynamic invocations.
-      UNALIGNED_STORE64(op, UNALIGNED_LOAD64(op - offset));
-      UNALIGNED_STORE64(op + 8, UNALIGNED_LOAD64(op - offset + 8));
+      UnalignedCopy64(op - offset, op);
+      UnalignedCopy64(op - offset + 8, op + 8);
     } else {
       if (space_left >= len + kMaxIncrementCopyOverflow) {
         IncrementalCopyFastPath(op - offset, op, len);
@@ -976,11 +1063,14 @@ class SnappyDecompressionValidator {
   inline bool CheckLength() const {
     return expected_ == produced_;
   }
-  inline bool Append(const char* ip, uint32 len, bool allow_fast_path) {
+  inline bool Append(const char* ip, size_t len) {
     produced_ += len;
     return produced_ <= expected_;
   }
-  inline bool AppendFromSelf(uint32 offset, uint32 len) {
+  inline bool TryFastAppend(const char* ip, size_t available, size_t length) {
+    return false;
+  }
+  inline bool AppendFromSelf(size_t offset, size_t len) {
     if (produced_ <= offset - 1u) return false;  // -1u catches offset==0
     produced_ += len;
     return produced_ <= expected_;

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/google-snappy/snappy.h
----------------------------------------------------------------------
diff --git a/src/snappy/google-snappy/snappy.h b/src/snappy/google-snappy/snappy.h
index 8d6ef22..8c2075f 100644
--- a/src/snappy/google-snappy/snappy.h
+++ b/src/snappy/google-snappy/snappy.h
@@ -144,10 +144,10 @@ namespace snappy {
   // decompression code should not rely on this guarantee since older
   // compression code may not obey it.
   static const int kBlockLog = 15;
-  static const int kBlockSize = 1 << kBlockLog;
+  static const size_t kBlockSize = 1 << kBlockLog;
 
   static const int kMaxHashTableBits = 14;
-  static const int kMaxHashTableSize = 1 << kMaxHashTableBits;
+  static const size_t kMaxHashTableSize = 1 << kMaxHashTableBits;
 
 }  // end namespace snappy
 

http://git-wip-us.apache.org/repos/asf/couchdb/blob/7cf76b8a/src/snappy/snappy.app.in
----------------------------------------------------------------------
diff --git a/src/snappy/snappy.app.in b/src/snappy/snappy.app.in
index 4ee1cda..25d37b5 100644
--- a/src/snappy/snappy.app.in
+++ b/src/snappy/snappy.app.in
@@ -1,7 +1,7 @@
 {application, snappy,
  [
   {description, "snappy compressor/decompressor Erlang NIF wrapper"},
-  {vsn, "1.0.3"},
+  {vsn, "1.0.5"},
   {registered, []},
   {applications, [
                   kernel,


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