AFIO v2: Relocate all the AFIO v2 files in fs_probe into the root hierarchy. AFIO v2 is now the master branch!

2 files changed, 652 insertions, 0 deletions

diff --git a/attic/detail/SpookyV2.cpp b/attic/detail/SpookyV2.cpp
new file mode 100644
index 00000000..76d745dd
--- /dev/null
+++ b/attic/detail/SpookyV2.cpp
@@ -0,0 +1,350 @@
+// Spooky Hash
+// A 128-bit noncryptographic hash, for checksums and table lookup
+// By Bob Jenkins.  Public domain.
+//   Oct 31 2010: published framework, disclaimer ShortHash isn't right
+//   Nov 7 2010: disabled ShortHash
+//   Oct 31 2011: replace End, ShortMix, ShortEnd, enable ShortHash again
+//   April 10 2012: buffer overflow on platforms without unaligned reads
+//   July 12 2012: was passing out variables in final to in/out in short
+//   July 30 2012: I reintroduced the buffer overflow
+//   August 5 2012: SpookyV2: d = should be d += in short hash, and remove extra mix from long hash
+
+#include <memory.h>
+#include "SpookyV2.h"
+
+#define ALLOW_UNALIGNED_READS 0
+
+//
+// short hash ... it could be used on any message, 
+// but it's used by Spooky just for short messages.
+//
+void SpookyHash::Short(
+    const void *message,
+    size_t length,
+    uint64 *hash1,
+    uint64 *hash2)
+{
+    uint64 buf[2*sc_numVars];
+    union 
+    { 
+        const uint8 *p8; 
+        uint32 *p32;
+        uint64 *p64; 
+        size_t i; 
+    } u;
+
+    u.p8 = (const uint8 *)message;
+    
+    if (!ALLOW_UNALIGNED_READS && (u.i & 0x7))
+    {
+        memcpy(buf, message, length);
+        u.p64 = buf;
+    }
+
+    size_t remainder = length%32;
+    uint64 a=*hash1;
+    uint64 b=*hash2;
+    uint64 c=sc_const;
+    uint64 d=sc_const;
+
+    if (length > 15)
+    {
+        const uint64 *end = u.p64 + (length/32)*4;
+        
+        // handle all complete sets of 32 bytes
+        for (; u.p64 < end; u.p64 += 4)
+        {
+            c += u.p64[0];
+            d += u.p64[1];
+            ShortMix(a,b,c,d);
+            a += u.p64[2];
+            b += u.p64[3];
+        }
+        
+        //Handle the case of 16+ remaining bytes.
+        if (remainder >= 16)
+        {
+            c += u.p64[0];
+            d += u.p64[1];
+            ShortMix(a,b,c,d);
+            u.p64 += 2;
+            remainder -= 16;
+        }
+    }
+    
+    // Handle the last 0..15 bytes, and its length
+    d += ((uint64)length) << 56;
+    switch (remainder)
+    {
+    case 15:
+    d += ((uint64)u.p8[14]) << 48;
+    case 14:
+        d += ((uint64)u.p8[13]) << 40;
+    case 13:
+        d += ((uint64)u.p8[12]) << 32;
+    case 12:
+        d += u.p32[2];
+        c += u.p64[0];
+        break;
+    case 11:
+        d += ((uint64)u.p8[10]) << 16;
+    case 10:
+        d += ((uint64)u.p8[9]) << 8;
+    case 9:
+        d += (uint64)u.p8[8];
+    case 8:
+        c += u.p64[0];
+        break;
+    case 7:
+        c += ((uint64)u.p8[6]) << 48;
+    case 6:
+        c += ((uint64)u.p8[5]) << 40;
+    case 5:
+        c += ((uint64)u.p8[4]) << 32;
+    case 4:
+        c += u.p32[0];
+        break;
+    case 3:
+        c += ((uint64)u.p8[2]) << 16;
+    case 2:
+        c += ((uint64)u.p8[1]) << 8;
+    case 1:
+        c += (uint64)u.p8[0];
+        break;
+    case 0:
+        c += sc_const;
+        d += sc_const;
+    }
+    ShortEnd(a,b,c,d);
+    *hash1 = a;
+    *hash2 = b;
+}
+
+
+
+
+// do the whole hash in one call
+void SpookyHash::Hash128(
+    const void *message, 
+    size_t length, 
+    uint64 *hash1, 
+    uint64 *hash2)
+{
+    if (length < sc_bufSize)
+    {
+        Short(message, length, hash1, hash2);
+        return;
+    }
+
+    uint64 h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11;
+    uint64 buf[sc_numVars];
+    uint64 *end;
+    union 
+    { 
+        const uint8 *p8; 
+        uint64 *p64; 
+        size_t i; 
+    } u;
+    size_t remainder;
+    
+    h0=h3=h6=h9  = *hash1;
+    h1=h4=h7=h10 = *hash2;
+    h2=h5=h8=h11 = sc_const;
+    
+    u.p8 = (const uint8 *)message;
+    end = u.p64 + (length/sc_blockSize)*sc_numVars;
+
+    // handle all whole sc_blockSize blocks of bytes
+    if (ALLOW_UNALIGNED_READS || ((u.i & 0x7) == 0))
+    {
+        while (u.p64 < end)
+        { 
+            Mix(u.p64, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        u.p64 += sc_numVars;
+        }
+    }
+    else
+    {
+        while (u.p64 < end)
+        {
+            memcpy(buf, u.p64, sc_blockSize);
+            Mix(buf, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        u.p64 += sc_numVars;
+        }
+    }
+
+    // handle the last partial block of sc_blockSize bytes
+    remainder = (length - ((const uint8 *)end-(const uint8 *)message));
+    memcpy(buf, end, remainder);
+    memset(((uint8 *)buf)+remainder, 0, sc_blockSize-remainder);
+    // ned March 2013: Don't mix in length related anything ((uint8 *)buf)[sc_blockSize-1] = remainder;
+    
+    // do some final mixing 
+    End(buf, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+    *hash1 = h0;
+    *hash2 = h1;
+}
+
+
+
+// init spooky state
+void SpookyHash::Init(uint64 seed1, uint64 seed2)
+{
+    m_length = 0;
+    m_remainder = 0;
+    m_state[0] = seed1;
+    m_state[1] = seed2;
+}
+
+
+// add a message fragment to the state
+void SpookyHash::Update(const void *message, size_t length)
+{
+    uint64 h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11;
+    size_t newLength = length + m_remainder;
+    uint8  remainder;
+    union 
+    { 
+        const uint8 *p8; 
+        uint64 *p64; 
+        size_t i; 
+    } u;
+    const uint64 *end;
+    
+    // Is this message fragment too short?  If it is, stuff it away.
+    if (newLength < sc_bufSize)
+    {
+        memcpy(&((uint8 *)m_data)[m_remainder], message, length);
+        m_length = length + m_length;
+        m_remainder = (uint8)newLength;
+        return;
+    }
+    
+    // init the variables
+    if (m_length < sc_bufSize)
+    {
+        h0=h3=h6=h9  = m_state[0];
+        h1=h4=h7=h10 = m_state[1];
+        h2=h5=h8=h11 = sc_const;
+    }
+    else
+    {
+        h0 = m_state[0];
+        h1 = m_state[1];
+        h2 = m_state[2];
+        h3 = m_state[3];
+        h4 = m_state[4];
+        h5 = m_state[5];
+        h6 = m_state[6];
+        h7 = m_state[7];
+        h8 = m_state[8];
+        h9 = m_state[9];
+        h10 = m_state[10];
+        h11 = m_state[11];
+    }
+    m_length = length + m_length;
+    
+    // if we've got anything stuffed away, use it now
+    if (m_remainder)
+    {
+        uint8 prefix = sc_bufSize-m_remainder;
+        memcpy(&(((uint8 *)m_data)[m_remainder]), message, prefix);
+        u.p64 = m_data;
+        Mix(u.p64, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        Mix(&u.p64[sc_numVars], h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        u.p8 = ((const uint8 *)message) + prefix;
+        length -= prefix;
+    }
+    else
+    {
+        u.p8 = (const uint8 *)message;
+    }
+    
+    // handle all whole blocks of sc_blockSize bytes
+    end = u.p64 + (length/sc_blockSize)*sc_numVars;
+    remainder = (uint8)(length-((const uint8 *)end-u.p8));
+    if (ALLOW_UNALIGNED_READS || (u.i & 0x7) == 0)
+    {
+        while (u.p64 < end)
+        { 
+            Mix(u.p64, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        u.p64 += sc_numVars;
+        }
+    }
+    else
+    {
+        while (u.p64 < end)
+        { 
+            memcpy(m_data, u.p8, sc_blockSize);
+            Mix(m_data, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        u.p64 += sc_numVars;
+        }
+    }
+
+    // stuff away the last few bytes
+    m_remainder = remainder;
+    memcpy(m_data, end, remainder);
+    
+    // stuff away the variables
+    m_state[0] = h0;
+    m_state[1] = h1;
+    m_state[2] = h2;
+    m_state[3] = h3;
+    m_state[4] = h4;
+    m_state[5] = h5;
+    m_state[6] = h6;
+    m_state[7] = h7;
+    m_state[8] = h8;
+    m_state[9] = h9;
+    m_state[10] = h10;
+    m_state[11] = h11;
+}
+
+
+// report the hash for the concatenation of all message fragments so far
+void SpookyHash::Final(uint64 *hash1, uint64 *hash2)
+{
+    // init the variables
+    if (m_length < sc_bufSize)
+    {
+        *hash1 = m_state[0];
+        *hash2 = m_state[1];
+        Short( m_data, m_length, hash1, hash2);
+        return;
+    }
+    
+    const uint64 *data = (const uint64 *)m_data;
+    uint8 remainder = m_remainder;
+    
+    uint64 h0 = m_state[0];
+    uint64 h1 = m_state[1];
+    uint64 h2 = m_state[2];
+    uint64 h3 = m_state[3];
+    uint64 h4 = m_state[4];
+    uint64 h5 = m_state[5];
+    uint64 h6 = m_state[6];
+    uint64 h7 = m_state[7];
+    uint64 h8 = m_state[8];
+    uint64 h9 = m_state[9];
+    uint64 h10 = m_state[10];
+    uint64 h11 = m_state[11];
+
+    if (remainder >= sc_blockSize)
+    {
+        // m_data can contain two blocks; handle any whole first block
+        Mix(data, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        data += sc_numVars;
+        remainder -= sc_blockSize;
+    }
+
+    // mix in the last partial block, and the length mod sc_blockSize
+    memset(&((uint8 *)data)[remainder], 0, (sc_blockSize-remainder));
+
+    ((uint8 *)data)[sc_blockSize-1] = remainder;
+    
+    // do some final mixing
+    End(data, h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+
+    *hash1 = h0;
+    *hash2 = h1;
+}
diff --git a/attic/detail/SpookyV2.h b/attic/detail/SpookyV2.h
new file mode 100644
index 00000000..41d312f8
--- /dev/null
+++ b/attic/detail/SpookyV2.h
@@ -0,0 +1,302 @@
+#ifndef SPOOKY_HASH_H
+#define SPOOKY_HASH_H
+
+//
+// SpookyHash: a 128-bit noncryptographic hash function
+// By Bob Jenkins, public domain
+//   Oct 31 2010: alpha, framework + SpookyHash::Mix appears right
+//   Oct 31 2011: alpha again, Mix only good to 2^^69 but rest appears right
+//   Dec 31 2011: beta, improved Mix, tested it for 2-bit deltas
+//   Feb  2 2012: production, same bits as beta
+//   Feb  5 2012: adjusted definitions of uint* to be more portable
+//   Mar 30 2012: 3 bytes/cycle, not 4.  Alpha was 4 but wasn't thorough enough.
+//   August 5 2012: SpookyV2 (different results)
+// 
+// Up to 3 bytes/cycle for long messages.  Reasonably fast for short messages.
+// All 1 or 2 bit deltas achieve avalanche within 1% bias per output bit.
+//
+// This was developed for and tested on 64-bit x86-compatible processors.
+// It assumes the processor is little-endian.  There is a macro
+// controlling whether unaligned reads are allowed (by default they are).
+// This should be an equally good hash on big-endian machines, but it will
+// compute different results on them than on little-endian machines.
+//
+// Google's CityHash has similar specs to SpookyHash, and CityHash is faster
+// on new Intel boxes.  MD4 and MD5 also have similar specs, but they are orders
+// of magnitude slower.  CRCs are two or more times slower, but unlike 
+// SpookyHash, they have nice math for combining the CRCs of pieces to form 
+// the CRCs of wholes.  There are also cryptographic hashes, but those are even 
+// slower than MD5.
+//
+
+#include <stddef.h>
+
+#ifdef _MSC_VER
+# define INLINE __forceinline
+  typedef  unsigned __int64 uint64;
+  typedef  unsigned __int32 uint32;
+  typedef  unsigned __int16 uint16;
+  typedef  unsigned __int8  uint8;
+#else
+# include <stdint.h>
+# define INLINE inline
+  typedef  uint64_t  uint64;
+  typedef  uint32_t  uint32;
+  typedef  uint16_t  uint16;
+  typedef  uint8_t   uint8;
+#endif
+
+
+class SpookyHash
+{
+public:
+    //
+    // SpookyHash: hash a single message in one call, produce 128-bit output
+    //
+    static void Hash128(
+        const void *message,  // message to hash
+        size_t length,        // length of message in bytes
+        uint64 *hash1,        // in/out: in seed 1, out hash value 1
+        uint64 *hash2);       // in/out: in seed 2, out hash value 2
+
+    //
+    // Hash64: hash a single message in one call, return 64-bit output
+    //
+    static uint64 Hash64(
+        const void *message,  // message to hash
+        size_t length,        // length of message in bytes
+        uint64 seed)          // seed
+    {
+        uint64 hash1 = seed;
+        Hash128(message, length, &hash1, &seed);
+        return hash1;
+    }
+
+    //
+    // Hash32: hash a single message in one call, produce 32-bit output
+    //
+    static uint32 Hash32(
+        const void *message,  // message to hash
+        size_t length,        // length of message in bytes
+        uint32 seed)          // seed
+    {
+        uint64 hash1 = seed, hash2 = seed;
+        Hash128(message, length, &hash1, &hash2);
+        return (uint32)hash1;
+    }
+
+    //
+    // Init: initialize the context of a SpookyHash
+    //
+    void Init(
+        uint64 seed1,       // any 64-bit value will do, including 0
+        uint64 seed2);      // different seeds produce independent hashes
+    
+    //
+    // Update: add a piece of a message to a SpookyHash state
+    //
+    void Update(
+        const void *message,  // message fragment
+        size_t length);       // length of message fragment in bytes
+
+
+    //
+    // Final: compute the hash for the current SpookyHash state
+    //
+    // This does not modify the state; you can keep updating it afterward
+    //
+    // The result is the same as if SpookyHash() had been called with
+    // all the pieces concatenated into one message.
+    //
+    void Final(
+        uint64 *hash1,    // out only: first 64 bits of hash value.
+        uint64 *hash2);   // out only: second 64 bits of hash value.
+
+    //
+    // left rotate a 64-bit value by k bytes
+    //
+    static INLINE uint64 Rot64(uint64 x, int k)
+    {
+        return (x << k) | (x >> (64 - k));
+    }
+
+    //
+    // This is used if the input is 96 bytes long or longer.
+    //
+    // The internal state is fully overwritten every 96 bytes.
+    // Every input bit appears to cause at least 128 bits of entropy
+    // before 96 other bytes are combined, when run forward or backward
+    //   For every input bit,
+    //   Two inputs differing in just that input bit
+    //   Where "differ" means xor or subtraction
+    //   And the base value is random
+    //   When run forward or backwards one Mix
+    // I tried 3 pairs of each; they all differed by at least 212 bits.
+    //
+    static INLINE void Mix(
+        const uint64 *data, 
+        uint64 &s0, uint64 &s1, uint64 &s2, uint64 &s3,
+        uint64 &s4, uint64 &s5, uint64 &s6, uint64 &s7,
+        uint64 &s8, uint64 &s9, uint64 &s10,uint64 &s11)
+    {
+      s0 += data[0];    s2 ^= s10;    s11 ^= s0;    s0 = Rot64(s0,11);    s11 += s1;
+      s1 += data[1];    s3 ^= s11;    s0 ^= s1;    s1 = Rot64(s1,32);    s0 += s2;
+      s2 += data[2];    s4 ^= s0;    s1 ^= s2;    s2 = Rot64(s2,43);    s1 += s3;
+      s3 += data[3];    s5 ^= s1;    s2 ^= s3;    s3 = Rot64(s3,31);    s2 += s4;
+      s4 += data[4];    s6 ^= s2;    s3 ^= s4;    s4 = Rot64(s4,17);    s3 += s5;
+      s5 += data[5];    s7 ^= s3;    s4 ^= s5;    s5 = Rot64(s5,28);    s4 += s6;
+      s6 += data[6];    s8 ^= s4;    s5 ^= s6;    s6 = Rot64(s6,39);    s5 += s7;
+      s7 += data[7];    s9 ^= s5;    s6 ^= s7;    s7 = Rot64(s7,57);    s6 += s8;
+      s8 += data[8];    s10 ^= s6;    s7 ^= s8;    s8 = Rot64(s8,55);    s7 += s9;
+      s9 += data[9];    s11 ^= s7;    s8 ^= s9;    s9 = Rot64(s9,54);    s8 += s10;
+      s10 += data[10];    s0 ^= s8;    s9 ^= s10;    s10 = Rot64(s10,22);    s9 += s11;
+      s11 += data[11];    s1 ^= s9;    s10 ^= s11;    s11 = Rot64(s11,46);    s10 += s0;
+    }
+
+    //
+    // Mix all 12 inputs together so that h0, h1 are a hash of them all.
+    //
+    // For two inputs differing in just the input bits
+    // Where "differ" means xor or subtraction
+    // And the base value is random, or a counting value starting at that bit
+    // The final result will have each bit of h0, h1 flip
+    // For every input bit,
+    // with probability 50 +- .3%
+    // For every pair of input bits,
+    // with probability 50 +- 3%
+    //
+    // This does not rely on the last Mix() call having already mixed some.
+    // Two iterations was almost good enough for a 64-bit result, but a
+    // 128-bit result is reported, so End() does three iterations.
+    //
+    static INLINE void EndPartial(
+        uint64 &h0, uint64 &h1, uint64 &h2, uint64 &h3,
+        uint64 &h4, uint64 &h5, uint64 &h6, uint64 &h7, 
+        uint64 &h8, uint64 &h9, uint64 &h10,uint64 &h11)
+    {
+        h11+= h1;    h2 ^= h11;   h1 = Rot64(h1,44);
+        h0 += h2;    h3 ^= h0;    h2 = Rot64(h2,15);
+        h1 += h3;    h4 ^= h1;    h3 = Rot64(h3,34);
+        h2 += h4;    h5 ^= h2;    h4 = Rot64(h4,21);
+        h3 += h5;    h6 ^= h3;    h5 = Rot64(h5,38);
+        h4 += h6;    h7 ^= h4;    h6 = Rot64(h6,33);
+        h5 += h7;    h8 ^= h5;    h7 = Rot64(h7,10);
+        h6 += h8;    h9 ^= h6;    h8 = Rot64(h8,13);
+        h7 += h9;    h10^= h7;    h9 = Rot64(h9,38);
+        h8 += h10;   h11^= h8;    h10= Rot64(h10,53);
+        h9 += h11;   h0 ^= h9;    h11= Rot64(h11,42);
+        h10+= h0;    h1 ^= h10;   h0 = Rot64(h0,54);
+    }
+
+    static INLINE void End(
+        const uint64 *data, 
+        uint64 &h0, uint64 &h1, uint64 &h2, uint64 &h3,
+        uint64 &h4, uint64 &h5, uint64 &h6, uint64 &h7, 
+        uint64 &h8, uint64 &h9, uint64 &h10,uint64 &h11)
+    {
+        h0 += data[0];   h1 += data[1];   h2 += data[2];   h3 += data[3];
+        h4 += data[4];   h5 += data[5];   h6 += data[6];   h7 += data[7];
+        h8 += data[8];   h9 += data[9];   h10 += data[10]; h11 += data[11];
+        EndPartial(h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        EndPartial(h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+        EndPartial(h0,h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11);
+    }
+
+    //
+    // The goal is for each bit of the input to expand into 128 bits of 
+    //   apparent entropy before it is fully overwritten.
+    // n trials both set and cleared at least m bits of h0 h1 h2 h3
+    //   n: 2   m: 29
+    //   n: 3   m: 46
+    //   n: 4   m: 57
+    //   n: 5   m: 107
+    //   n: 6   m: 146
+    //   n: 7   m: 152
+    // when run forwards or backwards
+    // for all 1-bit and 2-bit diffs
+    // with diffs defined by either xor or subtraction
+    // with a base of all zeros plus a counter, or plus another bit, or random
+    //
+    static INLINE void ShortMix(uint64 &h0, uint64 &h1, uint64 &h2, uint64 &h3)
+    {
+        h2 = Rot64(h2,50);  h2 += h3;  h0 ^= h2;
+        h3 = Rot64(h3,52);  h3 += h0;  h1 ^= h3;
+        h0 = Rot64(h0,30);  h0 += h1;  h2 ^= h0;
+        h1 = Rot64(h1,41);  h1 += h2;  h3 ^= h1;
+        h2 = Rot64(h2,54);  h2 += h3;  h0 ^= h2;
+        h3 = Rot64(h3,48);  h3 += h0;  h1 ^= h3;
+        h0 = Rot64(h0,38);  h0 += h1;  h2 ^= h0;
+        h1 = Rot64(h1,37);  h1 += h2;  h3 ^= h1;
+        h2 = Rot64(h2,62);  h2 += h3;  h0 ^= h2;
+        h3 = Rot64(h3,34);  h3 += h0;  h1 ^= h3;
+        h0 = Rot64(h0,5);   h0 += h1;  h2 ^= h0;
+        h1 = Rot64(h1,36);  h1 += h2;  h3 ^= h1;
+    }
+
+    //
+    // Mix all 4 inputs together so that h0, h1 are a hash of them all.
+    //
+    // For two inputs differing in just the input bits
+    // Where "differ" means xor or subtraction
+    // And the base value is random, or a counting value starting at that bit
+    // The final result will have each bit of h0, h1 flip
+    // For every input bit,
+    // with probability 50 +- .3% (it is probably better than that)
+    // For every pair of input bits,
+    // with probability 50 +- .75% (the worst case is approximately that)
+    //
+    static INLINE void ShortEnd(uint64 &h0, uint64 &h1, uint64 &h2, uint64 &h3)
+    {
+        h3 ^= h2;  h2 = Rot64(h2,15);  h3 += h2;
+        h0 ^= h3;  h3 = Rot64(h3,52);  h0 += h3;
+        h1 ^= h0;  h0 = Rot64(h0,26);  h1 += h0;
+        h2 ^= h1;  h1 = Rot64(h1,51);  h2 += h1;
+        h3 ^= h2;  h2 = Rot64(h2,28);  h3 += h2;
+        h0 ^= h3;  h3 = Rot64(h3,9);   h0 += h3;
+        h1 ^= h0;  h0 = Rot64(h0,47);  h1 += h0;
+        h2 ^= h1;  h1 = Rot64(h1,54);  h2 += h1;
+        h3 ^= h2;  h2 = Rot64(h2,32);  h3 += h2;
+        h0 ^= h3;  h3 = Rot64(h3,25);  h0 += h3;
+        h1 ^= h0;  h0 = Rot64(h0,63);  h1 += h0;
+    }
+    
+private:
+
+    //
+    // Short is used for messages under 192 bytes in length
+    // Short has a low startup cost, the normal mode is good for long
+    // keys, the cost crossover is at about 192 bytes.  The two modes were
+    // held to the same quality bar.
+    // 
+    static void Short(
+        const void *message,  // message (array of bytes, not necessarily aligned)
+        size_t length,        // length of message (in bytes)
+        uint64 *hash1,        // in/out: in the seed, out the hash value
+        uint64 *hash2);       // in/out: in the seed, out the hash value
+
+    // number of uint64's in internal state
+    static const size_t sc_numVars = 12;
+
+    // size of the internal state
+    static const size_t sc_blockSize = sc_numVars*8;
+
+    // size of buffer of unhashed data, in bytes
+    static const size_t sc_bufSize = 2*sc_blockSize;
+
+    //
+    // sc_const: a constant which:
+    //  * is not zero
+    //  * is odd
+    //  * is a not-very-regular mix of 1's and 0's
+    //  * does not need any other special mathematical properties
+    //
+    static const uint64 sc_const = 0xdeadbeefdeadbeefULL;
+
+    uint64 m_data[2*sc_numVars];   // unhashed data, for partial messages
+    uint64 m_state[sc_numVars];  // internal state of the hash
+    size_t m_length;             // total length of the input so far
+    uint8  m_remainder;          // length of unhashed data stashed in m_data
+};
+
+
+#endif