The Tor Browser: gfx/angle/src/third_party/murmurhash/MurmurHash3.cpp@129ffea94266 (annotated)

gfx/angle/src/third_party/murmurhash/MurmurHash3.cpp@129ffea94266 (annotated)

gfx/angle/src/third_party/murmurhash/MurmurHash3.cpp

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 //-----------------------------------------------------------------------------
 // MurmurHash3 was written by Austin Appleby, and is placed in the public
 // domain. The author hereby disclaims copyright to this source code.
 // Note - The x86 and x64 versions do _not_ produce the same results, as the
 // algorithms are optimized for their respective platforms. You can still
 // compile and run any of them on any platform, but your performance with the
 // non-native version will be less than optimal.
 #include "MurmurHash3.h"
 //-----------------------------------------------------------------------------
 // Platform-specific functions and macros
 // Microsoft Visual Studio
 #if defined(_MSC_VER)
 #define FORCE_INLINE	__forceinline
 #include <stdlib.h>
 #define ROTL32(x,y)	_rotl(x,y)
 #define ROTL64(x,y)	_rotl64(x,y)
 #define BIG_CONSTANT(x) (x)
 // Other compilers
 #else	// defined(_MSC_VER)
 #define	FORCE_INLINE __attribute__((always_inline))
 inline uint32_t rotl32 ( uint32_t x, int8_t r )
 {
   return (x << r) | (x >> (32 - r));
 }
 inline uint64_t rotl64 ( uint64_t x, int8_t r )
 {
   return (x << r) | (x >> (64 - r));
 }
 #define	ROTL32(x,y)	rotl32(x,y)
 #define ROTL64(x,y)	rotl64(x,y)
 #define BIG_CONSTANT(x) (x##LLU)
 #endif // !defined(_MSC_VER)
 //-----------------------------------------------------------------------------
 // Block read - if your platform needs to do endian-swapping or can only
 // handle aligned reads, do the conversion here
 FORCE_INLINE uint32_t getblock ( const uint32_t * p, int i )
 {
   return p[i];
 }
 FORCE_INLINE uint64_t getblock ( const uint64_t * p, int i )
 {
   return p[i];
 }
 //-----------------------------------------------------------------------------
 // Finalization mix - force all bits of a hash block to avalanche
 FORCE_INLINE uint32_t fmix ( uint32_t h )
 {
   h ^= h >> 16;
   h *= 0x85ebca6b;
   h ^= h >> 13;
   h *= 0xc2b2ae35;
   h ^= h >> 16;
   return h;
 }
 //----------
 FORCE_INLINE uint64_t fmix ( uint64_t k )
 {
   k ^= k >> 33;
   k *= BIG_CONSTANT(0xff51afd7ed558ccd);
   k ^= k >> 33;
   k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53);
   k ^= k >> 33;
   return k;
 }
 //-----------------------------------------------------------------------------
 void MurmurHash3_x86_32 ( const void * key, int len,
                           uint32_t seed, void * out )
 {
   const uint8_t * data = (const uint8_t*)key;
   const int nblocks = len / 4;
   uint32_t h1 = seed;
   const uint32_t c1 = 0xcc9e2d51;
   const uint32_t c2 = 0x1b873593;
   //----------
   // body
   const uint32_t * blocks = (const uint32_t *)(data + nblocks*4);
   for(int i = -nblocks; i; i++)
   {
     uint32_t k1 = getblock(blocks,i);
     k1 *= c1;
     k1 = ROTL32(k1,15);
     k1 *= c2;
     h1 ^= k1;
     h1 = ROTL32(h1,13);
     h1 = h1*5+0xe6546b64;
   }
   //----------
   // tail
   const uint8_t * tail = (const uint8_t*)(data + nblocks*4);
   uint32_t k1 = 0;
   switch(len & 3)
   {
   case 3: k1 ^= tail[2] << 16;
   case 2: k1 ^= tail[1] << 8;
   case 1: k1 ^= tail[0];
           k1 *= c1; k1 = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
   };
   //----------
   // finalization
   h1 ^= len;
   h1 = fmix(h1);
   *(uint32_t*)out = h1;
 }
 //-----------------------------------------------------------------------------
 void MurmurHash3_x86_128 ( const void * key, const int len,
                            uint32_t seed, void * out )
 {
   const uint8_t * data = (const uint8_t*)key;
   const int nblocks = len / 16;
   uint32_t h1 = seed;
   uint32_t h2 = seed;
   uint32_t h3 = seed;
   uint32_t h4 = seed;
   const uint32_t c1 = 0x239b961b;
   const uint32_t c2 = 0xab0e9789;
   const uint32_t c3 = 0x38b34ae5;
   const uint32_t c4 = 0xa1e38b93;
   //----------
   // body
   const uint32_t * blocks = (const uint32_t *)(data + nblocks*16);
   for(int i = -nblocks; i; i++)
   {
     uint32_t k1 = getblock(blocks,i*4+0);
     uint32_t k2 = getblock(blocks,i*4+1);
     uint32_t k3 = getblock(blocks,i*4+2);
     uint32_t k4 = getblock(blocks,i*4+3);
     k1 *= c1; k1  = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
     h1 = ROTL32(h1,19); h1 += h2; h1 = h1*5+0x561ccd1b;
     k2 *= c2; k2  = ROTL32(k2,16); k2 *= c3; h2 ^= k2;
     h2 = ROTL32(h2,17); h2 += h3; h2 = h2*5+0x0bcaa747;
     k3 *= c3; k3  = ROTL32(k3,17); k3 *= c4; h3 ^= k3;
     h3 = ROTL32(h3,15); h3 += h4; h3 = h3*5+0x96cd1c35;
     k4 *= c4; k4  = ROTL32(k4,18); k4 *= c1; h4 ^= k4;
     h4 = ROTL32(h4,13); h4 += h1; h4 = h4*5+0x32ac3b17;
   }
   //----------
   // tail
   const uint8_t * tail = (const uint8_t*)(data + nblocks*16);
   uint32_t k1 = 0;
   uint32_t k2 = 0;
   uint32_t k3 = 0;
   uint32_t k4 = 0;
   switch(len & 15)
   {
   case 15: k4 ^= tail[14] << 16;
   case 14: k4 ^= tail[13] << 8;
   case 13: k4 ^= tail[12] << 0;
            k4 *= c4; k4  = ROTL32(k4,18); k4 *= c1; h4 ^= k4;
   case 12: k3 ^= tail[11] << 24;
   case 11: k3 ^= tail[10] << 16;
   case 10: k3 ^= tail[ 9] << 8;
   case  9: k3 ^= tail[ 8] << 0;
            k3 *= c3; k3  = ROTL32(k3,17); k3 *= c4; h3 ^= k3;
   case  8: k2 ^= tail[ 7] << 24;
   case  7: k2 ^= tail[ 6] << 16;
   case  6: k2 ^= tail[ 5] << 8;
   case  5: k2 ^= tail[ 4] << 0;
            k2 *= c2; k2  = ROTL32(k2,16); k2 *= c3; h2 ^= k2;
   case  4: k1 ^= tail[ 3] << 24;
   case  3: k1 ^= tail[ 2] << 16;
   case  2: k1 ^= tail[ 1] << 8;
   case  1: k1 ^= tail[ 0] << 0;
            k1 *= c1; k1  = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
   };
   //----------
   // finalization
   h1 ^= len; h2 ^= len; h3 ^= len; h4 ^= len;
   h1 += h2; h1 += h3; h1 += h4;
   h2 += h1; h3 += h1; h4 += h1;
   h1 = fmix(h1);
   h2 = fmix(h2);
   h3 = fmix(h3);
   h4 = fmix(h4);
   h1 += h2; h1 += h3; h1 += h4;
   h2 += h1; h3 += h1; h4 += h1;
   ((uint32_t*)out)[0] = h1;
   ((uint32_t*)out)[1] = h2;
   ((uint32_t*)out)[2] = h3;
   ((uint32_t*)out)[3] = h4;
 }
 //-----------------------------------------------------------------------------
 void MurmurHash3_x64_128 ( const void * key, const int len,
                            const uint32_t seed, void * out )
 {
   const uint8_t * data = (const uint8_t*)key;
   const int nblocks = len / 16;
   uint64_t h1 = seed;
   uint64_t h2 = seed;
   const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);
   const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);
   //----------
   // body
   const uint64_t * blocks = (const uint64_t *)(data);
   for(int i = 0; i < nblocks; i++)
   {
     uint64_t k1 = getblock(blocks,i*2+0);
     uint64_t k2 = getblock(blocks,i*2+1);
     k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
     h1 = ROTL64(h1,27); h1 += h2; h1 = h1*5+0x52dce729;
     k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;
     h2 = ROTL64(h2,31); h2 += h1; h2 = h2*5+0x38495ab5;
   }
   //----------
   // tail
   const uint8_t * tail = (const uint8_t*)(data + nblocks*16);
   uint64_t k1 = 0;
   uint64_t k2 = 0;
   switch(len & 15)
   {
   case 15: k2 ^= uint64_t(tail[14]) << 48;
   case 14: k2 ^= uint64_t(tail[13]) << 40;
   case 13: k2 ^= uint64_t(tail[12]) << 32;
   case 12: k2 ^= uint64_t(tail[11]) << 24;
   case 11: k2 ^= uint64_t(tail[10]) << 16;
   case 10: k2 ^= uint64_t(tail[ 9]) << 8;
   case  9: k2 ^= uint64_t(tail[ 8]) << 0;
            k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;
   case  8: k1 ^= uint64_t(tail[ 7]) << 56;
   case  7: k1 ^= uint64_t(tail[ 6]) << 48;
   case  6: k1 ^= uint64_t(tail[ 5]) << 40;
   case  5: k1 ^= uint64_t(tail[ 4]) << 32;
   case  4: k1 ^= uint64_t(tail[ 3]) << 24;
   case  3: k1 ^= uint64_t(tail[ 2]) << 16;
   case  2: k1 ^= uint64_t(tail[ 1]) << 8;
   case  1: k1 ^= uint64_t(tail[ 0]) << 0;
            k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
   };
   //----------
   // finalization
   h1 ^= len; h2 ^= len;
   h1 += h2;
   h2 += h1;
   h1 = fmix(h1);
   h2 = fmix(h2);
   h1 += h2;
   h2 += h1;
   ((uint64_t*)out)[0] = h1;
   ((uint64_t*)out)[1] = h2;
 }
 //-----------------------------------------------------------------------------

The Tor Browser / annotate

gfx/angle/src/third_party/murmurhash/MurmurHash3.cpp@129ffea94266 (annotated)

gfx/angle/src/third_party/murmurhash/MurmurHash3.cpp